JP5556017B2 - ORGANIC ELECTROLUMINESCENT ELEMENT, DISPLAY DEVICE, LIGHTING DEVICE, AND ORGANIC ELECTROLUMINESCENT ELEMENT MATERIAL - Google Patents

Description

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

  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.

  On the other hand, an organic EL device has a structure in which a light-emitting layer containing a light-emitting compound is sandwiched between a cathode and an anode, and excitons (excitons) are generated by injecting electrons and holes into the light-emitting layer and recombining them. The device emits light by utilizing the emission of light (fluorescence / phosphorescence) when the exciton is deactivated, and can emit light at a voltage of several volts to several tens of volts. Therefore, it has a wide viewing angle, high visibility, and since it is a thin-film type completely solid element, it has attracted attention from the viewpoints of space saving and portability.

  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 (ηext) 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), for example, (ppy) ₂ Ir (acac), e 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 ortho-metalated iridium complexes).

  In addition, 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 Workshop 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.

  Organic EL devices using metal complexes typified by these iridium complexes are currently produced mainly by vapor deposition. Research on producing organic EL elements by coating methods has also been actively conducted, but the high cohesiveness of metal complexes represented by iridium complexes and the property of being easily precipitated when dissolved in a coating solution As a result, it is difficult to fabricate the element by the coating method. Therefore, it is desired that the cohesiveness of these metal complexes is reduced and that the precipitation is small when the coating solution is used.

  Recently, a technique in which a platinum complex having a large planarity is converted to a binuclear complex and its aggregation property is improved (for example, see Patent Documents 1 and 2), by introducing a dendrimer skeleton into the molecule, A technique for improving the solubility of a metal complex is disclosed (for example, see Patent Document 3), and a technique using a binuclear metal complex is disclosed (for example, see Patent Document 4 and Patent Document 5). And those having a disclosure of a binuclear complex in a specific conformation format (see, for example, Patent Documents 6, 7, 8, and 9). On the other hand, a short-wave blue metal complex using a ligand having high planarity is disclosed (for example, see Patent Document 10).

  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 improve the light emission lifetime of the device, and the performance that can withstand practical use has not been achieved sufficiently.

International Publication No. 04/93210 Pamphlet Japanese Patent Publication No. 2005-259377 Japanese Patent Publication No. 2007-214175 Japanese Patent Publication No. 2003-73388 International Publication No. 02/15645 Pamphlet Japanese Patent Publication No. 2006-298999 Japanese Patent Publication No. 2006-316162 International Publication No. 07/78183 Pamphlet International Publication No. 07/78185 pamphlet International Publication No. 07/095118 Pamphlet

  An object of the present invention is to provide an organic EL element having a high light emission efficiency, a long light emission lifetime, and a low driving voltage, a lighting device and a display device including the element, and a blue to blue-green short wave. It is to provide an organic EL element material which exhibits a good light emission and does not cause precipitation when the element is produced by a wet process.

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

1. In an organic electroluminescence device having at least a light emitting layer sandwiched between an anode and a cathode,
The organic electroluminescent element characterized by containing the compound represented by following General formula (1).

[In formula, E1a-E1q represents a carbon atom or a nitrogen atom respectively. The skeleton composed of E1a to E1q has a total of 18π electrons. R1a to R1i each represents a hydrogen atom or a substituent. L01 and M1, has a site that each coupled between one covalent bond and one coordinate bond, and represents a partial structure having one-three metal atoms. n1 represents an integer of 1 or 2. M1 represents a group 8-10 transition metal element in the periodic table. ]
2. 2. The organic electroluminescent element according to 1 above, wherein L01 represents a partial structure represented by the following general formula (2).

[Wherein, E2a to E2e, E2l to E2q, and E2c ′ each represent a carbon atom or a nitrogen atom. The skeleton composed of E2a to E2e, E2l to E2q, and E2c ′ has 12π electrons in total. R2a, R2b, R2f, R2k, R2g to R2i, and R2c ′ each represent a hydrogen atom or a substituent. R2k and R2f may be connected to each other to form a ring. L02 represents a partial structure having at least two rings each bonded to each of M1 and M2 by one covalent bond and one coordination bond. n2 represents an integer of 1 or 2. n0 represents an integer of 0 or 1. M2 represents a transition metal element of Group 8 to Group 10 in the periodic table. ]
3. 3. The organic electroluminescence device as described in 1 or 2 above, wherein the compound represented by the general formula (1) represents a compound represented by the following general formula (3).

[In formula, E1a-E1q represents a carbon atom or a nitrogen atom respectively. The skeleton composed of E1a to E1q has a total of 18π electrons. R1a to R1i each represents a hydrogen atom or a substituent. E2a to E2e, E2l to E2q, and E2c ′ each represent a carbon atom or a nitrogen atom. The skeleton composed of E2a to E2e, E2l to E2q, and E2c ′ has 12π electrons in total. R2a, R2b, R2f, R2k, R2g to R2i, and R2c ′ each represent a hydrogen atom or a substituent. R2k and R2f may be connected to each other to form a ring. L1 and L3 each represent a group having a site bonded to each of M1 and M2 by one covalent bond and one coordination bond, and having at least two rings as a partial structure; Represents a bond or a divalent to tetravalent linking group; n0 represents an integer of 0 or 1. n1 and n2 each represent an integer of 1 or 2. M1 and M2 each represent a group 8-10 group transition metal element in the periodic table. ]
4). 4. The organic electroluminescence as described in 3 above, wherein the compound represented by the general formula (3) is a compound represented by any one of the following general formulas (4), (5) or (6): element.

[Wherein, E1a to E1q each represent a carbon atom or a nitrogen atom, and the skeleton composed of E1a to E1q has a total of 18π electrons. R1a to R1i each represents a hydrogen atom or a substituent. E2a to E2e, E2f to E2k, E2l to E2q, and E2c ′ each represent a carbon atom or a nitrogen atom.

The skeleton composed of E2a to E2e, the skeleton composed of E2a to E2e and E2c ′, the skeleton composed of E2f to E2k, and the skeleton composed of E2l to E2q each have 6π electrons. R2a, R2b, R2c, R2d, R2e, R2f, R2k, R2g to R2i, and R2c ′ each represent a hydrogen atom or a substituent. L1 and L3 each represent a group having a site bonded to each of M1 and M2 by one covalent bond and one coordination bond, and having at least two rings as a partial structure; Represents a bond or a divalent to tetravalent linking group; n1 and n2 each represent an integer of 1 or 2. M1 and M2 represent group 8 to group 10 transition metal elements in the periodic table. ]
5. The skeleton composed of E1a to E1q of the compound represented by any one of the general formulas (4), (5), and (6) represents a partial structure represented by the following general formula (7) 5. The organic electroluminescence device as described in 4 above.

[In formula, E1b-E1e represents a carbon atom or a nitrogen atom respectively. R1a to R1i each represents a hydrogen atom or a substituent. n1 represents an integer of 1 or 2. M1 represents a group 8-10 transition metal element in the periodic table. * Represents a binding site. ]
6). 6. The organic electroluminescence device as described in 5 above, wherein the partial structure represented by the general formula (7) represents a partial structure represented by the following general formula (8).

[Wherein, R1a to R1i each represents a hydrogen atom or a substituent. n1 represents an integer of 1 or 2. M1 represents a group 8-10 transition metal element in the periodic table. * Represents a binding site. ]
7). 6. The organic electroluminescence device according to 5 above, wherein the partial structure represented by the general formula (7) represents a partial structure represented by the following general formula (9).

[Wherein, R1a to R1i each represents a hydrogen atom or a substituent. n1 represents an integer of 1 or 2. M1 represents a group 8-10 transition metal element in the periodic table. * Represents a binding site. ]
8). The partial structure represented by L01 described in 1 above, the partial structure represented by General Formula (2) described in 2 above, M2, E2a to E2e, E2l to E2q in General Formula (3) described in 3 above , E2c 'backbone comprised from the group consisting of or in the general formula (5) described in the 4,, M2, E2a~E2e, E2l~E2q , E2c' one from the group consisting of consisting skeletal is The organic electroluminescence device according to any one of 1 to 7, which represents a partial structure represented by the following general formula (10).

[Wherein, E2b to E2e and E2c ′ each represent a carbon atom or a nitrogen atom. R2a, R2b, R2f, R2k, R2g to R2i, and R2c ′ each represent a hydrogen atom or a substituent. n2 represents an integer of 1 or 2. M2 represents a transition metal element of Group 8 to Group 10 in the periodic table. * Represents a binding site. ]
9. The partial structure represented by L01 described in 1 above, the partial structure represented by General Formula (2) described in 2 above, M2, E2a to E2e, E2l to E2q in General Formula (3) described in 3 above , skeletal comprised from the group consisting of E2c 'or in the general formula (4) described in the 4,, M2, E2a～E2e, one from the group consisting of E2l~E2q of configured skeletal the following general 8. The organic electroluminescence device according to any one of 1 to 7, which has a partial structure represented by formula (11).

[Wherein, E2b to E2e each represent a carbon atom or a nitrogen atom. R2a, R2b, R2f, R2k, and R2g to R2i each represent a hydrogen atom or a substituent. n2 represents an integer of 1 or 2. M2 represents a transition metal element of Group 8 to Group 10 in the periodic table. * Represents a binding site. ]
10. The partial structure represented by L01 described in 1 above, the partial structure represented by General Formula (2) described in 2 above, M2, E2a to E2e, E2l to E2q in General Formula (3) described in 3 above , E2c skeleton composed from the group consisting of ', in the general formula (6) according to the had or 4, M2, E2a~E2e, E2f~E2k, either composed skeleton from the group consisting of E2l~E2q The organic electroluminescent device according to any one of 1 to 7 above, which has a partial structure represented by the following general formula (12).

[Wherein, E2b to E2k each represent a carbon atom or a nitrogen atom. R2a to R2i each represents a hydrogen atom or a substituent. n2 represents an integer of 1 or 2. M2 represents a transition metal element of Group 8 to Group 10 in the periodic table. * Represents a binding site. ]
11. 9. The organic electroluminescence device as described in 8 above, wherein the partial structure represented by the general formula (10) is a partial structure represented by the following general formula (13).

[Wherein, R2a, R2b, R2f, R2k, R2g to R2i, and R2c ′ each represent a hydrogen atom or a substituent. n2 represents an integer of 1 or 2. M2 represents a transition metal element of Group 8 to Group 10 in the periodic table. * Represents a binding site. ]
12 10. The organic electroluminescence device as described in 9 above, wherein the partial structure represented by the general formula (11) is a partial structure represented by the following general formula (14).

[Wherein, R2a, R2b, R2f, R2k, R2g to R2i each represents a hydrogen atom or a substituent. n2 represents an integer of 1 or 2. M2 represents a transition metal element of Group 8 to Group 10 in the periodic table. * Represents a binding site. ]
13. 11. The partial structure represented by the general formula (12) is a partial structure represented by the following general formula (15) or a partial structure represented by the following general formula (16). Organic electroluminescence element.

[Wherein, R2a to R2i each represents a hydrogen atom or a substituent. n2 represents an integer of 1 or 2. M2 represents a transition metal element of Group 8 to Group 10 in the periodic table. * Represents a binding site. ]
14 Any one of 1 to 13 above, wherein a layer containing at least one compound represented by any one of the general formulas (1) and (3) to (6) is a light emitting layer as a constituent layer. 2. The organic electroluminescence device according to item 1.

  15. As a constituent layer, it has an organic layer containing at least one compound represented by any one of the general formulas (1) and (3) to (6), and the organic layer was formed using a wet process. 15. The organic electroluminescence device according to any one of 1 to 14, wherein the organic electroluminescence device is characterized in that

  16. Said M1 and M2 represent platinum or iridium, respectively, The organic electroluminescent element of any one of said 1-15 characterized by the above-mentioned.

  17. In the organic electroluminescent element according to any one of 1 to 16, the compound represented by the general formula (1) described in 1 above, and the general formula (3) described in 3 above are represented. 5. An organic electroluminescence device material comprising a compound or at least one compound represented by any one of the general formulas (4), (5) and (6) described in 4 above.

  18. 17. A display device comprising the organic electroluminescence element according to any one of 1 to 16.

  19. An illuminating device comprising the organic electroluminescence element according to any one of 1 to 16 above.

  According to the present invention, an organic EL element having a high light emission efficiency, a long light emission lifetime, and a low driving voltage, and an illumination device and a display device including the element are provided. Thus, it was possible to provide an organic EL element material in which no precipitation occurs when the element is manufactured by a wet process.

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.

  In the organic electroluminescence element of the present invention, the structure defined in any one of 1 to 16 above shows high emission efficiency, a long emission lifetime, and a low drive voltage organic EL element. An illumination device and a display device provided can be provided.

  In addition, the present inventors succeeded in molecular design of an organic EL element material useful for the organic electroluminescence element of the present invention. The organic electroluminescence element material of the present invention is an organic EL element material that emits blue to blue-green short-wave light and does not cause precipitation when the element is produced by a wet process.

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

  The present inventors paid attention to the organic EL element material used for the light emitting layer of the organic EL element, and examined various metal complex compounds used as a light emitting dopant.

  The present inventors have introduced a substituent into the basic skeleton of a metal complex, and thus it is not a conventionally known approach to control the wavelength or improve the lifetime, but to expand the π-conjugated surface of the condensed ring. Various complexes were studied under the focus of increasing stability.

  As a result, the improvement tendency of lifetime was found in several condensed ring structures. However, when a fused ring as known so far is introduced, the red shift of the emission wavelength is remarkable, resulting in green and red emission.

  The inventors further studied and introduced a condensed ring as shown in the compound (also referred to as a metal complex) containing a partial structure represented by the general formulas (1) to (16) according to the present invention. In this case, a light emitting dopant having a small emission wavelength shift and a long lifetime at a desired emission wavelength has been successfully developed.

  Further examination of this new basic skeleton has the disadvantage that the π-conjugate plane becomes larger, and the planarity becomes higher, so that the association between metal complexes becomes a problem, and the lifetime of the device is remarkably reduced. I understood.

  The compound represented by the general formula (1), the compound represented by the general formula (3) or the compound represented by any one of the general formulas (4), (5) or (6) (transition metal) The feature of the compound (also called complex compound) is that it is a complex of a binuclear structure. This compensates for the shortcomings of highly planar ligands and contributes to the improvement of the luminous efficiency.

  Furthermore, it was also found that by using a binuclear complex, there was an effect of improving solubility and an effect of suppressing a decrease in lifetime.

  The compound represented by the general formula (1), the compound represented by the general formula (3) or the compound represented by any one of the general formulas (4), (5) or (6) (transition metal) The complex compound) may have a plurality of ligands depending on the valence of the transition metal element constituting each of the binuclei, but the ligands may all be the same, and each may have a different structure. You may have a scale.

  Here, the ligand is represented by the compound represented by the general formula (1), the compound represented by the general formula (3), or any one of the general formulas (4), (5), or (6). A transition metal element (M1, M2, etc. in the formula) from the compound (also referred to as a transition metal complex compound) or a partial structure represented by any one of the general formula (2) or the general formulas (7) to (16) ) Are each a ligand.

(Conventionally known ligand)
Moreover, as what is called a ligand, the said trader can use together a well-known ligand (it is also called a coordination compound) as a ligand as needed.

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

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

(Transition metal elements of groups 8 to 10 of the periodic table)
The compound represented by the general formula (1), the compound represented by the general formula (3) or the compound represented by any one of the general formulas (4), (5) or (6) (transition metal) Formation of a compound (also referred to as a transition metal complex, a metal complex, or a metal complex compound) including a partial structure represented by any one of general formula (2) or general formulas (7) to (16) As the metal used in (in each general formula, described as M1 and M2), group 8-10 transition metal elements (also referred to simply as transition metals) of the periodic table of elements are used. Among them, iridium, Platinum is a preferred transition metal element.

(Contained layer of transition metal complex according to the present invention)
The compound represented by the general formula (1), the compound represented by the general formula (3) or the compound represented by any one of the general formulas (4), (5) or (6) (transition metal) As a layer containing a transition metal complex compound containing a partial structure represented by any one of the general formula (2) or the general formulas (7) to (16), a layer that transports charges (charge) The transport layer is not particularly limited, but is preferably a hole transport layer or a light-emitting layer, a light-emitting layer or an electron blocking layer, more preferably a light-emitting layer or an electron blocking layer, and particularly preferably a light-emitting layer.

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

  First, the compound represented by the general formula (1) according to the present invention will be described, and then the compound represented by the general formula (3) or any one of the general formulas (4), (5), or (6) The compound represented (it is also called a transition metal complex compound), the partial structure represented by either General formula (2) or General formula (7)-(16) is demonstrated.

<< Compound Represented by Formula (1) >>
The compound represented by the general formula (1) according to the present invention will be described.

  First, a skeleton composed of E1a to E1q having a total of 18π electrons will be described.

  In the general formula (1), the ring formed by E1a to E1e represents a 5-membered aromatic heterocycle, for example, an oxazole ring, thiazole ring, oxadiazole ring, oxatriazole ring, isoxazole ring, tetrazole ring , Thiadiazole ring, thiatriazole ring, isothiazole ring, thiophene ring, furan ring, pyrrole ring, imidazole ring, pyrazole ring, triazole ring and the like.

  Among these, a pyrazole ring, an imidazole ring, an oxazole ring, and a thiazole ring are preferable, and an imidazole ring, a pyrazole ring, and a triazole ring are more preferable, and an imidazole ring is particularly preferable.

  Each of these rings may further have a substituent described later.

  In general formula (1), the ring formed by E1f to E1k represents a 6-membered aromatic hydrocarbon ring or a 6-membered aromatic heterocycle.

  Examples of the 6-membered aromatic hydrocarbon ring formed by E1f to E1k include a benzene ring. Furthermore, you may have the substituent mentioned later.

  Examples of the 6-membered aromatic heterocycle formed by E1f to E1k include a pyridine ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring, and a triazine ring.

  Each of these rings may further have a substituent described later.

  In the general formula (1), the ring formed by E1l to E1q represents a 6-membered aromatic hydrocarbon ring or a 6-membered aromatic heterocycle, and these rings are represented by E1f in the general formula (1). Are each synonymous with a 6-membered aromatic hydrocarbon ring or a 6-membered aromatic heterocycle formed by ~ E1k.

  In the general formula (1), the substituents represented by R1a to R1i are, for example, alkyl groups (for example, methyl group, ethyl group, propyl group, isopropyl group, tert-butyl group, pentyl group, hexyl group, octyl group). 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 group (aromatic hydrocarbon ring group, aromatic carbocyclic group) Also referred to as an aryl group, for example, phenyl group, p-chlorophenyl group, mesityl group, tolyl group, xylyl group, Phthalyl group, anthryl group, azulenyl group, acenaphthenyl group, fluorenyl group, phenanthryl group, indenyl group, pyrenyl group, biphenylyl group, etc.), aromatic heterocyclic group (for example, furyl group, thienyl group, pyridyl group, pyridazinyl group, pyrimidinyl) Group, pyrazinyl group, triazinyl group, imidazolyl group, pyrazolyl group, thiazolyl group, quinazolinyl group, carbazolyl group, carbolinyl group, diazacarbazolyl group (one of the carbon atoms constituting the carboline ring of the carbolinyl group is nitrogen An phthalazinyl group), a heterocyclic group (eg, pyrrolidyl group, imidazolidyl group, morpholyl group, oxazolidyl group, etc.), an alkoxy group (eg, methoxy group, ethoxy group, propyloxy group, pentyl) Oxy group, hex Oxy group, octyloxy group, dodecyloxy group, etc.), cycloalkoxy group (eg, cyclopentyloxy group, cyclohexyloxy group, etc.), aryloxy group (eg, phenoxy group, naphthyloxy group, etc.), alkylthio group (eg, methylthio group) Group, ethylthio group, propylthio group, pentylthio group, hexylthio group, octylthio group, dodecylthio group, etc.), cycloalkylthio group (eg, cyclopentylthio group, cyclohexylthio group, etc.), arylthio group (eg, phenylthio group, naphthylthio group, etc.) , Alkoxycarbonyl groups (eg, methyloxycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, octyloxycarbonyl group, dodecyloxycarbonyl group, etc.), aryloxycarbonyl groups (eg For example, phenyloxycarbonyl group, naphthyloxycarbonyl group, etc.), sulfamoyl group (for example, aminosulfonyl group, methylaminosulfonyl group, dimethylaminosulfonyl group, butylaminosulfonyl group, hexylaminosulfonyl group, cyclohexylaminosulfonyl group, octylamino) Sulfonyl group, dodecylaminosulfonyl group, phenylaminosulfonyl group, naphthylaminosulfonyl 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. An acyloxy group (eg, acetyloxy group, ethylcarbonyloxy group, butylcarbonyloxy group, octylcarbonyloxy group, dodecylcarbonyloxy group, phenylcarbonyloxy group, etc.), amide group (eg, methylcarbonylamino group, ethylcarbonylamino group) 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, dimethylaminocarbonyl group, propylaminocarbonyl group, pentylamino) Carbonyl group, cyclohexylaminocarbonyl group, octylaminocarbonyl group, 2-ethylhexylaminocarbonyl group, dodecylaminocarbonyl group, phenylaminocarbonyl group, naphthylaminocarbonyl group, 2-pyridylaminocarbonyl group, etc.), ureido group (for example, methylureido) Group, ethylureido group, pentylureido group, cyclohexylureido group, octylureido group, dodecylureido group, phenylureido group naphthylureido group, 2-pyridylaminoureido group, etc.), sulfinyl group (for example, methylsulfinyl group, ethylsulfinyl group, Butylsulfinyl group, cyclohexylsulfinyl group, 2-ethylhexylsulfinyl group, dodecylsulfinyl group, phenylsulfinyl group, naphthylsulfinyl Nyl group, 2-pyridylsulfinyl group, etc.), alkylsulfonyl group (eg, methylsulfonyl group, ethylsulfonyl group, butylsulfonyl group, cyclohexylsulfonyl group, 2-ethylhexylsulfonyl group, dodecylsulfonyl group, etc.), arylsulfonyl group or hetero Arylsulfonyl group (for example, phenylsulfonyl group, naphthylsulfonyl group, 2-pyridylsulfonyl group, etc.), amino group (for example, amino group, ethylamino group, dimethylamino group, butylamino group, cyclopentylamino group, 2-ethylhexylamino) Group, dodecylamino group, anilino group, naphthylamino group, 2-pyridylamino group, etc.), halogen atom (eg, fluorine atom, chlorine atom, bromine atom etc.), fluorinated hydrocarbon group (eg, fluoromethyl group, trifluoro) Romethyl 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.) ), A phosphono group, and the like.

  Among these substituents, an alkyl group, an aromatic hydrocarbon group, and an aromatic heterocyclic group are preferably used.

  These substituents may be further substituted with the above substituents. In addition, a plurality of these substituents may be bonded to each other to form a ring.

(Partial structure represented by L01)
In the general formula (1), L01 represents a partial structure having at least one metal atom, each having a site bonded to M1, one covalent bond and one coordination bond. The partial structure represented by the general formula (2) is used.

(Partial structure represented by general formula (2))
The partial structure represented by the general formula (2) according to the present invention will be described.

  In the general formula (2), the substituents represented by R2a, R2b, R2f, R2k, R2g to R2i, and R2c ′ have the same meaning as the substituents represented by R1a to R1i in the general formula (1). is there.

  In the general formula (2), the skeleton composed of E2a to E2e, E2l to E2q, and E2c ′ has a total of 12π electrons. Specifically, the ring formed by E2a to E2e and E2c ′ represents a 6-membered aromatic hydrocarbon ring or a 5-membered or 6-membered aromatic heterocycle.

  The ring formed by E2l to E2q represents a 6-membered aromatic hydrocarbon ring or a 6-membered aromatic heterocycle.

  In the general formula (2), examples of the 6-membered aromatic hydrocarbon ring formed by E2a to E2e and E2c ′ include a benzene ring. Moreover, you may have said substituent further.

  In the general formula (2), it represents a 5-membered aromatic heterocycle formed by E2a to E2e, E2c ′, for example, an oxazole ring, thiazole ring, oxadiazole ring, oxatriazole ring, isoxazole ring, tetrazole ring , Thiadiazole ring, thiatriazole ring, isothiazole ring, thiophene ring, furan ring, pyrrole ring, imidazole ring, pyrazole ring, triazole ring and the like.

  Among these, a pyrazole ring, an imidazole ring, an oxazole ring, and a thiazole ring are preferable, and an imidazole ring, a pyrazole ring, and a triazole ring are more preferable, and an imidazole ring is particularly preferable.

  Each of these rings may further have the above substituent.

  In the general formula (2), the 6-membered aromatic hydrocarbon ring or 6-membered aromatic heterocycle formed by E2l to E2q is a 6-membered member formed by E1f to E1k in the general formula (1), respectively. Are each synonymous with the aromatic hydrocarbon ring or 6-membered aromatic heterocyclic ring.

  In the general formula (2), L02 represents a partial structure having at least two rings each bonded to M1 and M2 by one covalent bond and one coordination bond.

  The at least two rings are preferably those formed by a combination of a 5-membered or 6-membered aromatic heterocyclic ring and a 6-membered aromatic hydrocarbon ring.

  The 5-membered aromatic heterocycle has the same meaning as the 5-membered aromatic heterocycle formed by E2a to E2e and E2c ′ in the general formula (2).

  The 6-membered aromatic heterocycle or 6-membered aromatic hydrocarbon ring is a 6-membered aromatic hydrocarbon ring or 6-membered aromatic heterocycle formed by E1f to E1k, respectively, in the general formula (1). Each is synonymous with a ring.

  Among the compounds represented by the general formula (1) according to the present invention, the compound represented by the general formula (3) is preferable.

<< Compound Represented by Formula (3) >>
The compound represented by formula (3), which is a preferred embodiment of the compound represented by formula (1) according to the present invention, will be described.

  In general formula (3), the ring formed by E1a-E1e is synonymous with the 5-membered aromatic heterocycle formed by E1a-E1e in general formula (1).

  In general formula (3), the ring formed by E1f to E1k is the ring formed by E1f to E1k in general formula (1) (6-membered aromatic hydrocarbon ring or 6-membered aromatic heterocycle). It is synonymous with.

  In general formula (3), the ring formed by E1l to E1q is the ring formed by E1l to E1q in general formula (1) (6-membered aromatic hydrocarbon ring or 6-membered aromatic heterocycle). It is synonymous with.

  In general formula (3), the ring formed by E2a to E2e or the ring formed from E2a to E2e and E2c ′ is formed from E1a to E1e in general formula (1) and in general formula (1). The ring is synonymous with a 5-membered aromatic heterocycle or a ring formed by E1f to E1k (6-membered aromatic hydrocarbon ring or 6-membered aromatic heterocycle).

  In general formula (3), the ring formed by E2l to E2q is the ring formed by E1l to E1q in general formula (1) (6-membered aromatic hydrocarbon ring or 6-membered aromatic heterocycle). It is synonymous with.

  In the general formula (3), the substituents represented by R1a to R1i, R2a, R2b, R2f, R2k, R2g to R2i, and the substituents represented by R2c ′, respectively, are represented by R1a to R1i in the general formula (1). It is synonymous with the substituent represented by each R1i.

  In the general formula (3), L1 and L3 each have a site bonded to each of M1 and M2 by one covalent bond and one coordination bond, and have at least two rings as a partial structure. And the two rings include a 5-membered aromatic heterocycle formed by E1a to E1e in the general formula (1), and a 6-membered aromatic formed by E1f to E1k in the general formula (1). A combination of two rings selected from an aromatic hydrocarbon ring or a 6-membered aromatic heterocycle is preferred.

  In the general formula (3), examples of the divalent linking group represented by L2 include hydrocarbon groups such as alkylene groups, alkenylene groups, alkynylene groups, and arylene groups, as well as the alkylene groups, the alkenylene groups, and the alkynylene groups. In the arylene group, each of them may contain a hetero atom (for example, a nitrogen atom, a sulfur atom, a silicon atom, etc.), or a thiophene-2,5-diyl group or pyrazine-2,3-diyl. It may be a divalent linking group derived from a compound having an aromatic heterocycle (also called a heteroaromatic compound) such as a group, or a chalcogen atom such as oxygen or sulfur.

  Further, it may be a group linked via a hetero atom such as an alkylimino group, a dialkylsilanediyl group or a diarylgermandiyl group.

  Examples of the alkylene group used as the divalent linking group represented by L2 include, for example, ethylene group, trimethylene group, tetramethylene group, propylene group, ethylethylene group, pentamethylene group, hexamethylene group, 2,2, 4-trimethylhexamethylene group, heptamethylene group, octamethylene group, nonamethylene group, decamethylene group, undecamethylene group, dodecamethylene group, cyclohexylene group (for example, 1,6-cyclohexanediyl group, etc.), cyclopentylene group (For example, 1,5-cyclopentanediyl group) and the like.

  Examples of the alkenylene group used as the divalent linking group represented by L2 include a propenylene group, a vinylene group, and a 4-propyl-2-pentenylene group.

  Examples of the alkynylene group used as the divalent linking group represented by L2 include an ethynylene group and a 3-pentynylene group.

  The arylene group used as the divalent linking group represented by L2 includes o-phenylene group, m-phenylene group, p-phenylene group, naphthalenediyl group, anthracenediyl group, naphthacenediyl group, pyrenediyl group, and naphthylnaphthalenediyl group. Group, biphenyldiyl group (for example, 3,3′-biphenyldiyl group, 4,4′-biphenyldiyl group, 3,6-biphenyldiyl group, etc.), terphenyldiyl group, quaterphenyldiyl group, kinkphenyldiyl Group, sexiphenyldiyl group, septiphenyldiyl group, octiphenyldiyl group, nobiphenyldiyl group, deciphenyldiyl group and the like.

  Examples of the group having a divalent heterocyclic group used as the divalent linking group represented by L2 (also referred to as a heteroarylene group) include, for example, oxazolediyl group, pyrimidinediyl group, pyridazinediyl group, pyrandiyl group, pyrroline Examples include diyl group, imidazoline diyl group, imidazolidine diyl group, pyrazolidine diyl group, pyrazoline diyl group, piperidine diyl group, piperazine diyl group, morpholine diyl group, quinuclidine diyl group, and 1,3,4 -Triazole-2,5-diyl group, 1,3,4-oxadiazole-2,5-diyl group, thiophene-2,5-diyl group, pyrrole-2,5-diyl group, pyridine-2,6 -Diyl group, dibenzofuran-2,8-diyl group, dibenzothiophene-2,8-diyl group, N-phenylcarba -3,6-diyl group, N-ethylcarbazole-3,6-diyl group, 4,4-diazacarbazole-3,6-diyl group, pyrazine-2,3-diyl group, It may be a divalent linking group derived from a compound having an aromatic heterocycle (also referred to as a heteroaromatic compound).

  In the general formula (3), examples of the trivalent linking group represented by L2 include ethanetriyl, propanetriyl, butanetriyl, pentanetriyl, hexanetriyl, heptanetriyl, and octanetriyl. Group, nonanetriyl group, decanetriyl group, undecanetriyl group, dodecanetriyl group, cyclohexanetriyl group, cyclopentanetriyl group, benzenetriyl group, naphthalenetriyl group, triazinetriyl group, etc. In addition, one in which one divalent linking group is further attached to each of the above divalent linking groups can be used as the trivalent group.

  In the general formula (3), examples of the tetravalent linking group represented by L2 include a propanediylidene group, 1,3-propanediyl-2-ylidene group, butanediylidene group, pentanediylidene group, and hexanediylidene group. Group, heptanediylidene group, octanediylidene group, nonanediylidene group, decandiylidene group, undecandiylidene group, dodecandiylidene group, cyclohexanediylidene group, cyclopentanediylidene group, benzenetetrayl group, naphthalenetetrayl group, etc. In addition, the trivalent group represented by L described above further has one linking group (which becomes tetravalent when the divalent linking group is substituted) or the like is used as the tetravalent linking group. be able to.

  In general formula (1), the divalent to tetravalent linking group represented by L2 is preferably a group derived from an aromatic hydrocarbon ring or an aromatic heterocyclic ring, at least one metal complex. A group derived from a partial structure having two groups, a group derived from a partial structure having two metal complexes, a group derived from a carbazole derivative, a group derived from a dibenzofuran derivative, a group derived from a dibenzothiophene derivative, A group derived from a phenylamine derivative, a carboline derivative or a diazacarbazole derivative (a diazacarbazole derivative refers to a group in which at least one of the carbon atoms constituting the carboline ring is substituted with a nitrogen atom) It is preferable that

  Among the compounds represented by the general formula (3) according to the present invention, the compounds represented by any one of the above general formulas (4) to (6) are more preferably used.

<< Compound Represented by Formula (4) >>
In general formula (4), the ring formed by E1a-E1e is synonymous with the 5-membered aromatic heterocyclic ring formed by E1a-E1e in general formula (1).

  In general formula (4), the ring formed by E1f to E1k is the ring formed by E1f to E1k in general formula (1) (6-membered aromatic hydrocarbon ring or 6-membered aromatic heterocycle). It is synonymous with.

  In general formula (4), the ring formed by E1l to E1q is the ring formed by E1l to E1q in general formula (1) (6-membered aromatic hydrocarbon ring or 6-membered aromatic heterocycle). It is synonymous with.

  In general formula (4), the ring formed by E2a to E2e has the same meaning as the 5-membered aromatic heterocycle formed by E1a to E1e in general formula (1).

  In general formula (4), the ring formed by E2l to E2q is the ring formed by E1l to E1q in general formula (1) (6-membered aromatic hydrocarbon ring or 6-membered aromatic heterocycle). It is synonymous with.

  In the general formula (4), each of the substituents represented by R1a to R1i and each of the substituents represented by R2a, R2b, R2f, R2k, and R2g to R2i is represented by R1a to R1i in the general formula (1). It is synonymous with the substituent represented.

  In general formula (4), the groups represented by L1 and L3 have the same meanings as the groups represented by L1 and L3 in general formula (3).

<< Compound Represented by Formula (5) >>
In general formula (5), the ring formed by E1a-E1e is synonymous with the 5-membered aromatic heterocyclic ring formed by E1a-E1e in general formula (1).

  In general formula (5), the ring formed by E1f to E1k is the ring formed by E1f to E1k in general formula (1) (6-membered aromatic hydrocarbon ring or 6-membered aromatic heterocycle). It is synonymous with.

  In general formula (5), the ring formed by E1l to E1q is the ring formed by E1l to E1q in general formula (1) (6-membered aromatic hydrocarbon ring or 6-membered aromatic heterocycle). It is synonymous with.

  In general formula (5), the ring formed by E2a to E2e and E2c ′ and the ring formed from E2l to E2q are the ring formed by E1l to E1q in general formula (1) (6-membered aromatic A hydrocarbon ring or a 6-membered aromatic heterocyclic ring).

  In the general formula (5), the substituents represented by R1a to R1i, R2a, R2b, R2c ′, R2f, R2k, and R2g to R2i, respectively, are represented by R1a to R1i in the general formula (1). It is synonymous with the substituent represented by each R1i.

  In general formula (5), the groups represented by L1 and L3 have the same meanings as the groups represented by L1 and L3 in general formula (3).

<< Compound Represented by Formula (6) >>
In general formula (6), the ring formed by E1a-E1e is synonymous with the 5-membered aromatic heterocyclic ring formed by E1a-E1e in general formula (1).

  In general formula (6), the ring formed by E1f to E1k is the ring formed by E1f to E1k in general formula (1) (6-membered aromatic hydrocarbon ring or 6-membered aromatic heterocycle). It is synonymous with.

  In general formula (6), the ring formed by E1l to E1q is the ring formed by E1l to E1q in general formula (1) (6-membered aromatic hydrocarbon ring or 6-membered aromatic heterocycle). It is synonymous with.

  In general formula (6), the ring formed by E2a to E2e has the same meaning as the 5-membered aromatic heterocycle formed by E1a to E1e in general formula (1).

  In general formula (6), the ring formed by E2l to E2q and the ring formed by E2f to E2k are each a ring formed by E1l to E1q (6-membered aromatic hydrocarbon) in general formula (1). Ring or 6-membered aromatic heterocycle).

  In General Formula (6), the substituents represented by R1a to R1i, R2a, R2b, R2c, R2d, R2e, and R2f to R2i, respectively, are represented by R1a to R1i in General Formula (1). Are the same as the substituents represented by

  In general formula (6), the groups represented by L1 and L3 have the same meanings as the groups represented by L1 and L3 in general formula (3).

  Furthermore, the preferable aspect of the compound represented by either of General formula (4)-(6) which concerns on this invention is demonstrated.

  The skeleton represented by E1a to E1q of the compound represented by any one of the general formulas (4) to (6) according to the present invention preferably represents the partial structure represented by the general formula (7), As a more preferred embodiment, a partial structure represented by the general formula (8) or (9) can be mentioned.

<< Partial Structure Represented by General Formula (7), General Formula (8), or General Formula (9) >>
In general formula (7), the substituents represented by R1a to R1i have the same meanings as the substituents represented by R1a to R1i in general formula (1).

  Furthermore, the preferable aspect of the compound represented by General formula (1) based on this invention is demonstrated.

<< Partial structure represented by any one of general formulas (10) to (16) >>
Furthermore, in the present invention, the partial structure represented by L01 of the compound represented by the general formula (1), the partial structure represented by the general formula (2), and the compound represented by the general formula (3) A skeleton composed of the group consisting of M2, E2a to E2e, E2l to E2q and E2c ′, a skeleton composed of the group consisting of M2, E2a to E2e and E2l to E2q in the general formula (4) 5), a skeleton composed of the group consisting of M2, E2a to E2e, E2l to E2q, E2c ′ or a group consisting of M2, E2a to E2e, E2f to E2k, E2l to E2q in the general formula (6) It is preferable that any one of the skeletons represents a partial structure represented by any one of the general formulas (10), (11), and (12).
(A) The partial structure represented by the general formula (10) represents the partial structure represented by the general formula (13).
(B) The partial structure represented by the general formula (11) represents the partial structure represented by the general formula (14).
(C) The partial structure represented by the general formula (12) of the Senki represents the partial structure represented by the general formula (15) or (16).
There are cases.

(Partial structure represented by general formula (10))
In general formula (10), the ring formed by N (nitrogen atom), E2b to E2e, and E2c ′ is a 6-membered nitrogen-containing aromatic heterocycle, such as a pyridine ring, pyridazine ring, pyrimidine ring, pyrazine Ring, triazine ring and the like.

  In General Formula (10), R2a, R2b, R2f, R2k, R2g to R2i, and R2c ′ each have the same meaning as the substituent represented by R1a to R1i in General Formula (1), respectively. It is.

(Partial structure represented by general formula (11))
In the general formula (11), the ring formed by N (nitrogen atom) and E2b to E2e is a 5-membered nitrogen-containing aromatic heterocycle, such as an oxazole ring, a thiazole ring, an oxadiazole ring, Examples thereof include an oxatriazole ring, an isoxazole ring, a tetrazole ring, a thiadiazole ring, a thiatriazole ring, an isothiazole ring, a pyrrole ring, an imidazole ring, a pyrazole ring, and a triazole ring.

  In the general formula (11), the substituents represented by R2a, R2b, R2f, R2k, and R2g to R2i have the same meanings as the substituents represented by R1a to R1i in the general formula (1).

(Partial structure represented by general formula (12))
In the general formula (12), the ring formed by N (nitrogen atom) and E2b to E2e is a 5-membered nitrogen-containing aromatic heterocycle, and includes, for example, an oxazole ring, a thiazole ring, an oxadiazole ring, Examples thereof include an oxatriazole ring, an isoxazole ring, a tetrazole ring, a thiadiazole ring, a thiatriazole ring, an isothiazole ring, a pyrrole ring, an imidazole ring, a pyrazole ring, and a triazole ring.

  In the general formula (12), the ring formed by E2f to E2k represents a 6-membered aromatic hydrocarbon ring or a 6-membered aromatic heterocycle, and these rings are represented by E1f in the general formula (1). Are each synonymous with a 6-membered aromatic hydrocarbon ring or a 6-membered aromatic heterocycle formed by ~ E1k.

  In the general formula (12), the substituents represented by R2a to R2i have the same meanings as the substituents represented by R1a to R1i in the general formula (1).

(Partial structure represented by general formula (13))
In the general formula (13), R2a, R2b, R2f, R2k, R2g to R2i, and R2c ′ each have the same meaning as the substituent represented by R1a to R1i in the general formula (1). It is.

(Partial structure represented by general formula (14))
In the general formula (14), the substituents represented by R2a, R2b, R2f, R2k, and R2g to R2i have the same definitions as the substituents represented by R1a to R1i in the general formula (1).

(Partial structure represented by either general formula (15) or general formula (16))
In the partial structure represented by either general formula (15) or general formula (16), the substituents represented by R2a to R2i are the substituents represented by R1a to R1i in general formula (1), respectively. Synonymous with group.

  Hereinafter, the compound represented by the general formula (1) according to the present invention, the compound represented by the general formula (3), or the compound represented by any one of the general formulas (4), (5), or (6) ( A compound having a partial structure represented by any one of the general formula (2) and the general formulas (7) to (16), which is a preferable embodiment as a partial structure of each compound. Specific examples of (also referred to as a metal complex or a metal complex compound) are shown, but the present invention is not limited to these.

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

  Hereinafter, the constituent layers of the organic EL device of the present invention will be described in detail.

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

(I) Anode / light emitting layer / electron transport layer / cathode (ii) Anode / hole transport layer / light emitting layer / electron transport layer / cathode (iii) Anode / hole transport layer / light emitting layer / hole blocking layer / electron Transport layer / cathode (iv) Anode / hole transport layer / light emitting layer / hole blocking layer / electron transport layer / cathode buffer layer / cathode (v) Anode / anode buffer layer / hole transport layer / light emitting layer / hole Blocking layer / electron transport layer / cathode buffer layer / cathode (vi) Anode / hole transport layer / electron block layer / light emitting layer / hole block layer / electron transport layer / cathode In the organic EL device of the present invention, blue light emission The light emission maximum wavelength of the layer is preferably in the range of 430 nm to 480 nm, the green light emission layer is preferably a monochromatic light emitting layer having a light emission maximum wavelength in the range of 510 nm to 550 nm, and the red light emission layer is in the range of the light emission maximum wavelength of 600 nm to 640 nm. This is a display device using these. It is preferred.

  Alternatively, a white light emitting layer may be formed by laminating at least three light emitting layers. Further, a non-light emitting intermediate layer may be provided between the light emitting layers.

  Furthermore, the organic EL element of the present invention is preferably a white light emitting layer, and an illumination device using these is preferable.

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

<Light emitting layer>
The light emitting layer according to the present invention is a layer that emits light by recombination of electrons and holes injected from the electrode, the electron transport layer, or the hole transport layer, and the light emitting portion is in the layer of the light emitting layer. May be the interface between the light emitting layer and the adjacent layer.

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

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

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

(Host compound (also called luminescent host))
The host compound used in the present invention will be described.

  Here, in the present invention, the host compound is defined as a compound having a phosphorescence quantum yield of phosphorescence emission of less than 0.1 at room temperature (25 ° C.). The phosphorescence quantum yield is preferably less than 0.01. Moreover, it is preferable that the mass ratio in the layer is 20% or more among the compounds contained in a light emitting layer.

  As the host compound, known host compounds may be used alone or in combination of two or more. By using a plurality of types of host compounds, it is possible to adjust the movement of charges, and the organic EL element can be made highly efficient. Moreover, it becomes possible to mix different light emission by using multiple types of light emission dopants mentioned later, and, thereby, arbitrary luminescent colors can be obtained.

  Moreover, you may use together a conventionally well-known light emission dopant as shown below. It may be a conventionally known 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 known host compounds that may be used in combination with the present invention, there are 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). preferable.

  Specific examples of host compounds that can be used in combination with the present invention are shown below, but the present invention is not limited thereto.

  Specific examples of known host compounds further include compounds described in the following documents.

  JP-A-2001-257076, 2002-308855, 2001-313179, 2002-319491, 2001-357777, 2002-334786, 2002-8860, 2002-334787, 2002-15871, 2002-334788, 2002-43056, 2002-334789, 2002-75645, 2002-338579, 2002-105445 gazette, 2002-343568 gazette, 2002-141173 gazette, 2002-352957 gazette, 2002-203683 gazette, 2002-363227 gazette, 2002-231453 gazette, No. 003-3165, No. 2002-234888, No. 2003-27048, No. 2002-255934, No. 2002-286061, No. 2002-280183, No. 2002-299060, No. 2002. -302516, 2002-305083, 2002-305084, 2002-308837, and the like.

(Luminescent dopant)
The light emitting dopant according to the present invention will be described.

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

(Phosphorescent dopant)
The phosphorescent dopant according to the present invention will be described.

  The phosphorescent dopant according to the present invention is a compound in which light emission from an excited triplet is observed. Specifically, the phosphorescent dopant is a compound that emits phosphorescence at room temperature (25 ° C.) and has a phosphorescence quantum yield of 25. Although it is defined as a compound of 0.01 or more at ° C., a preferable phosphorescence quantum yield is 0.1 or more.

  The phosphorescence quantum yield can be measured by the method described in Spectroscopic II, page 398 (1992 edition, Maruzen) of Experimental Chemistry Course 4 of the 4th edition. Although the phosphorescence quantum yield in a solution can be measured using various solvents, the phosphorescence dopant according to the present invention achieves the phosphorescence quantum yield (0.01 or more) in any solvent. That's fine.

  There are two types of light emission of phosphorescent dopants in principle. One is the recombination of carriers on the host compound to which carriers are transported to generate an excited state of the host compound, and this energy is transferred to the phosphorescent dopant. The energy transfer type that obtains light emission from the phosphorescent dopant, and the other is that the phosphorescent dopant becomes a carrier trap, carrier recombination occurs on the phosphorescent dopant, and light emission from the phosphorescent dopant is obtained. Although it is a trap type, in any case, the excited state energy of the phosphorescent dopant is required to be lower than the excited state energy of the host compound.

  The phosphorescent dopant can be appropriately selected from known materials used for the light emitting layer of the organic EL device.

  The phosphorescent dopant according to the present invention is preferably a complex compound containing a group 8-10 metal in the periodic table of elements, more preferably an iridium compound, an osmium compound, or a platinum compound (platinum complex compound), Rare earth complexes, most preferably iridium compounds.

  As the compound used as the phosphorescent dopant according to the present invention, the compound represented by the general formula (1), the compound represented by the general formula (3) or the general formula (4), (5) ) Or (6) (also referred to as a transition metal complex compound) or a transition containing a partial structure represented by any one of the general formula (2) or the general formulas (7) to (16) Metal complex compounds are preferred.

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

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

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

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

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

  The details of the anode buffer layer (hole injection layer) are described in JP-A-9-45479, JP-A-9-260062, JP-A-8-288069 and the like. As a specific example, copper phthalocyanine is used. Examples thereof include a phthalocyanine buffer layer represented by an oxide, an oxide buffer layer represented by vanadium oxide, an amorphous carbon buffer layer, and a polymer buffer layer using a conductive polymer such as polyaniline (emeraldine) or polythiophene.

  The details of the cathode buffer layer (electron injection layer) are described in JP-A-6-325871, JP-A-9-17574, JP-A-10-74586, and the like. Specifically, strontium, aluminum, etc. Metal buffer layer typified by lithium, alkali metal compound buffer layer typified by lithium fluoride, alkaline earth metal compound buffer layer typified by magnesium fluoride, oxide buffer layer typified by aluminum oxide, etc. . The buffer layer (injection layer) is preferably a very thin film, and the film thickness is preferably in the range of 0.1 nm to 5 μm although it depends on the material.

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

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

  Moreover, the structure of the electron carrying layer mentioned later can be used as a hole-blocking layer concerning this invention as needed.

  The hole blocking layer of the organic EL device of the present invention is preferably provided adjacent to the light emitting layer.

  The hole blocking layer contains the carbazole derivative, carboline derivative, diazacarbazole derivative (one in which one of the carbon atoms constituting the carboline ring of the carboline derivative is replaced with a nitrogen atom) mentioned as the host compound. It is preferable to do.

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

  The ionization potential is defined by the energy required to emit an electron at the HOMO (highest occupied molecular orbital) level of the compound to the vacuum level, and can be obtained by the following method, for example.

  (1) Using Gaussian 98 (Gaussian 98, Revision A.11.4, MJ Frisch, et al, Gaussian, Inc., Pittsburgh PA, 2002.), a molecular orbital calculation software manufactured by Gaussian, USA The ionization potential can be obtained as a value obtained by rounding off the second decimal place of the value (eV unit converted value) calculated by performing structural optimization using B3LYP / 6-31G *. This calculation value is effective because the correlation between the calculation value obtained by this method and the experimental value is high.

  (2) The ionization potential can also be obtained by a method of directly measuring by photoelectron spectroscopy. For example, a method known as ultraviolet photoelectron spectroscopy can be suitably used by using a low energy electron spectrometer “Model AC-1” manufactured by Riken Keiki Co., Ltd.

  The partial structure represented by any one of the general formulas (1) to (4), the partial structure represented by any one of the general formulas (5) to (8), and the general formula (9) according to the present invention. To (12) or a compound having a partial structure represented by any one of the general formulas (13) to (16) may be contained in the hole 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.

  Moreover, the structure of the positive hole transport layer mentioned later can be used as an electron blocking layer as needed. The film thickness of the hole blocking layer and the electron transport layer according to the present invention is preferably 3 nm to 100 nm, and more preferably 5 nm to 30 nm.

  The partial structure represented by any one of the general formulas (1) to (4), the partial structure represented by any one of the general formulas (5) to (8), and the general formula (9) according to the present invention. It is also possible to contain in the electron blocking layer a compound having a partial structure represented by any one of (12) or a partial structure represented by any one of the general formulas (13) to (16).

《Hole transport layer》
The hole transport layer is made of a hole transport material having a function of transporting holes, and in a broad sense, a hole injection layer and an electron blocking layer are also included in the hole transport layer. The hole transport layer can be provided as a single layer or a plurality of layers.

  The hole transport material has any one of hole injection or transport and electron barrier properties, and may be either organic or inorganic. For example, triazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives and pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, oxazole derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, Examples thereof include stilbene derivatives, silazane derivatives, aniline copolymers, and conductive polymer oligomers, particularly thiophene oligomers.

  The above-mentioned materials can be used as the hole transport material, but it is preferable to use a porphyrin compound, an aromatic tertiary amine compound and a styrylamine compound, particularly an aromatic tertiary amine compound.

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

  Furthermore, a polymer material in which these materials are introduced into a polymer chain or these materials are used as a polymer main chain can also be used. In addition, inorganic compounds such as p-type-Si and p-type-SiC can also be used as the hole injection material and the hole transport material.

  JP-A-11-251067, J. Org. Huang et. al. A so-called p-type hole transport material as described in a book (Applied Physics Letters 80 (2002), p. 139) can also be used. In the present invention, these materials are preferably used because a light-emitting element with higher efficiency can be obtained.

  The hole transport layer can be formed by thinning the hole transport material by a known method such as a vacuum deposition method, a spin coating method, a casting method, a printing method including an ink jet method, or an LB method. it can. Although there is no restriction | limiting in particular about the film thickness of a positive hole transport layer, Usually, 5 nm-about 5 micrometers, Preferably it is 5 nm-200 nm. The hole transport layer may have a single layer structure composed of one or more of the above materials.

  Alternatively, a hole transport layer having a high p property doped with impurities can be used. Examples thereof include JP-A-4-297076, JP-A-2000-196140, 2001-102175, J. Pat. Appl. Phys. 95, 5773 (2004), and the like.

  In the present invention, it is preferable to use a hole transport layer having such a high p property because a device with lower power consumption can be produced.

《Electron transport layer》
The electron transport layer is made of a material having a function of transporting electrons, and in a broad sense, an electron injection layer and a hole blocking layer are also included in the electron transport layer. The electron transport layer can be provided as a single layer or a plurality of layers.

  Conventionally, in the case of a single electron transport layer and a plurality of layers, an electron transport material (also serving as a hole blocking material) used for an electron transport layer adjacent to the light emitting layer on the cathode side is injected from the cathode. As long as it has a function of transferring electrons to the light-emitting layer, any material can be selected and used from among conventionally known compounds. For example, nitro-substituted fluorene derivatives, diphenylquinone derivatives Thiopyrandioxide derivatives, carbodiimides, fluorenylidenemethane derivatives, anthraquinodimethane and anthrone derivatives, oxadiazole derivatives and the like.

  Furthermore, in the above oxadiazole derivative, a thiadiazole derivative in which the oxygen atom of the oxadiazole ring is substituted with a sulfur atom, and a quinoxaline derivative having a quinoxaline ring known as an electron withdrawing group can also be used as an electron transport material. Furthermore, a polymer material in which these materials are introduced into a polymer chain or these materials are used as a polymer main chain can also be used.

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

  In addition, metal-free or metal phthalocyanine, or those having terminal ends substituted with an alkyl group or a sulfonic acid group can be preferably used as the electron transporting material. In addition, the distyrylpyrazine derivative exemplified as the material of the light emitting layer can also be used as an electron transport material, and an inorganic semiconductor such as n-type-Si, n-type-SiC, etc. as in the case of the hole injection layer and the hole transport layer. Can also be used as an electron transporting material.

  The electron transport layer can be formed by thinning the electron transport material by a known method such as a vacuum deposition method, a spin coating method, a casting method, a printing method including an ink jet method, or an LB method. Although there is no restriction | limiting in particular about the film thickness of an electron carrying layer, Usually, 5 nm-about 5 micrometers, Preferably it is 5 nm-200 nm. The electron transport layer may have a single layer structure composed of one or more of the above materials.

  Further, an electron transport layer having a high n property doped with impurities can also be used. Examples thereof include JP-A-4-297076, JP-A-10-270172, JP-A-2000-196140, 2001-102175, J.A. Appl. Phys. 95, 5773 (2004), and the like.

  In the present invention, it is preferable to use an electron transport layer having such a high n property because an element with lower power consumption can be manufactured.

"anode"
As the anode in the organic EL element, an electrode material made of a metal, an alloy, an electrically conductive compound, or a mixture thereof having a high work function (4 eV or more) is preferably used. Specific examples of such electrode materials include metals such as Au, and conductive transparent materials such as CuI, indium tin oxide (ITO), SnO ₂ , and ZnO.

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

  Or when using the substance which can be apply | coated like an organic electroconductivity compound, wet film-forming methods, such as a printing system and a coating system, can also be used. When light emission is extracted from the anode, it is desirable that the transmittance be greater than 10%, and the sheet resistance as the anode is preferably several hundred Ω / □ or less. Further, although the film thickness depends on the material, it is usually selected in the range of 10 nm to 1000 nm, preferably 10 nm to 200 nm.

"cathode"
On the other hand, as the cathode, a material having a low work function (4 eV or less) metal (referred to as an electron injecting metal), an alloy, an electrically conductive compound, and a mixture thereof as an electrode material is used. Specific examples of such electrode materials include sodium, sodium-potassium alloy, magnesium, lithium, magnesium / copper mixture, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, aluminum / aluminum oxide (Al ₂ O ₃ ) Mixtures, indium, lithium / aluminum mixtures, rare earth metals and the like. Among these, from the point of durability against electron injection and oxidation, etc., a mixture of an electron injecting metal and a second metal which is a stable metal having a larger work function than this, for example, a magnesium / silver mixture, Magnesium / aluminum mixtures, magnesium / indium mixtures, aluminum / aluminum oxide (Al ₂ O ₃ ) mixtures, lithium / aluminum mixtures, aluminum and the like are preferred.

  The cathode can be produced by forming a thin film of these electrode materials by a method such as vapor deposition or sputtering. The sheet resistance as a cathode is preferably several hundred Ω / □ or less, and the film thickness is usually selected in the range of 10 nm to 5 μm, preferably 50 nm to 200 nm. In order to transmit the emitted light, if either one of the anode or the cathode of the organic EL element is transparent or translucent, the light emission luminance is improved, which is convenient.

  Moreover, after producing the said metal by the film thickness of 1 nm-20 nm to a cathode, the transparent or semi-transparent cathode can be produced by producing the electroconductive transparent material quoted by description of the anode on it, By applying this, an element in which both the anode and the cathode are transmissive can be manufactured.

《Support substrate》
As a support substrate (hereinafter also referred to as a substrate, substrate, substrate, support, etc.) that can be used in the organic EL device of the present invention, there is no particular limitation on the type of glass, plastic, etc., and it is transparent. May be opaque. When extracting light from the support substrate side, the support substrate is preferably transparent. Examples of the transparent support substrate preferably used include glass, quartz, and a transparent resin film. A particularly preferable support substrate is a resin film capable of giving flexibility to the organic EL element.

  Examples of the resin film include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyethylene, polypropylene, cellophane, cellulose diacetate, cellulose triacetate, cellulose acetate butyrate, cellulose acetate propionate (CAP), Cellulose esters such as cellulose acetate phthalate (TAC) and cellulose nitrate or derivatives thereof, polyvinylidene chloride, polyvinyl alcohol, polyethylene vinyl alcohol, syndiotactic polystyrene, polycarbonate, norbornene resin, polymethylpentene, polyether ketone, polyimide , Polyethersulfone (PES), polyphenylene sulfide, polysulfones Cycloolefin resins such as polyetherimide, polyetherketoneimide, polyamide, fluororesin, nylon, polymethylmethacrylate, acrylic or polyarylate, Arton (trade name, manufactured by JSR) or Appel (trade name, manufactured by Mitsui Chemicals) Can be mentioned.

On the surface of the resin film, an inorganic film, an organic film, or a hybrid film of both may be formed. Water vapor permeability (25 ± 0.5 ° C.) measured by a method according to JIS K 7129-1992. , Relative humidity (90 ± 2)% RH) is preferably 0.01 g / (m ² · 24 h) or less, and further, oxygen measured by a method according to JIS K 7126-1987. A high barrier film having a permeability of 10 ⁻³ ml / (m ² · 24 h · atm) or less and a water vapor permeability of 10 ⁻⁵ g / (m ² · 24 h) or less is preferable.

  As a material for forming the barrier film, any material may be used as long as it has a function of suppressing entry of elements that cause deterioration of elements such as moisture and oxygen. For example, silicon oxide, silicon dioxide, silicon nitride, or the like can be used. Further, in order to improve the brittleness of the film, it is more preferable to have a laminated structure of these inorganic layers and organic material layers. Although there is no restriction | limiting in particular about the lamination | stacking order of an inorganic layer and an organic layer, It is preferable to laminate | stack both alternately several times.

  The method for forming the barrier film is not particularly limited. For example, vacuum deposition, sputtering, reactive sputtering, molecular beam epitaxy, cluster ion beam, ion plating, plasma polymerization, atmospheric pressure plasma polymerization A plasma CVD method, a laser CVD method, a thermal CVD method, a coating method, or the like can be used, but an atmospheric pressure plasma polymerization method described in JP 2004-68143 A is particularly preferable.

  Examples of the opaque support substrate include metal plates such as aluminum and stainless steel, films, opaque resin substrates, and ceramic substrates.

  The external extraction efficiency at room temperature of light emission of the organic EL device of the present invention is preferably 1% or more, more preferably 5% or more.

  Here, the external extraction quantum efficiency (%) = the number of photons emitted to the outside of the organic EL element / the number of electrons sent to the organic EL element × 100.

  In addition, a hue improvement filter such as a color filter may be used in combination, or a color conversion filter that converts the emission color from the organic EL element into multiple colors using a phosphor. In the case of using a color conversion filter, the λmax of light emission of the organic EL element is preferably 480 nm or less.

<Sealing>
As a sealing means used for this invention, the method of adhere | attaching a sealing member, an electrode, and a support substrate with an adhesive agent can be mentioned, for example.

  As a sealing member, it should just be arrange | positioned so that the display area | region of an organic EL element may be covered, and concave plate shape or flat plate shape may be sufficient. Further, transparency and electrical insulation are not particularly limited.

  Specific examples include a glass plate, a polymer plate / film, and a metal plate / film. Examples of the glass plate include soda-lime glass, barium / strontium-containing glass, lead glass, aluminosilicate glass, borosilicate glass, barium borosilicate glass, and quartz. Examples of the polymer plate include polycarbonate, acrylic, polyethylene terephthalate, polyether sulfide, and polysulfone. Examples of the metal plate include those made of one or more metals or alloys selected from the group consisting of stainless steel, iron, copper, aluminum, magnesium, nickel, zinc, chromium, titanium, molybdenum, silicon, germanium, and tantalum.

  In the present invention, a polymer film and a metal film can be preferably used because the element can be thinned.

Furthermore, the polymer film has an oxygen permeability of 1 × 10 ⁻³ ml / (m ² · 24 h · atm) or less measured by a method according to JIS K 7126-1987, and a method according to JIS K 7129-1992. It is preferable that the water vapor permeability (25 ± 0.5 ° C., relative humidity (90 ± 2)% RH) measured in (1) is 1 × 10 ⁻³ g / (m ² · 24 h) or less.

  For processing the sealing member into a concave shape, sandblasting, chemical etching, or the like is used.

  Specific examples of the adhesive include photocuring and thermosetting adhesives having reactive vinyl groups such as acrylic acid oligomers and methacrylic acid oligomers, and moisture curing adhesives such as 2-cyanoacrylates. be able to.

  Moreover, heat | fever and chemical curing types (two-component mixing), such as an epoxy type, can be mentioned. Moreover, hot-melt type polyamide, polyester, and polyolefin can be mentioned. Moreover, a cationic curing type ultraviolet curing epoxy resin adhesive can be mentioned.

  In addition, since an organic EL element may deteriorate by heat processing, what can be adhesive-hardened from room temperature to 80 degreeC is preferable. A desiccant may be dispersed in the adhesive. Application | coating of the adhesive agent to a sealing part may use commercially available dispenser, and may print like screen printing.

  In addition, it is also preferable that the electrode and the organic layer are coated on the outside of the electrode facing the support substrate with the organic layer interposed therebetween, and an inorganic or organic layer is formed in contact with the support substrate to form a sealing film. . In this case, the material for forming the film may be any material that has a function of suppressing intrusion of elements that cause deterioration of elements such as moisture and oxygen. For example, silicon oxide, silicon dioxide, silicon nitride, or the like may be used. it can.

  Further, in order to improve the brittleness of the film, it is preferable to have a laminated structure of these inorganic layers and layers made of organic materials.

  The method for forming these films is not particularly limited. For example, vacuum deposition, sputtering, reactive sputtering, molecular beam epitaxy, cluster ion beam, ion plating, plasma polymerization, atmospheric pressure plasma A combination method, plasma CVD method, laser CVD method, thermal CVD method, coating method, or the like can be used.

  In the gap between the sealing member and the display area of the organic EL element, an inert gas such as nitrogen or argon, or an inert liquid such as fluorinated hydrocarbon or silicon oil can be injected in the gas phase and liquid phase. preferable. A vacuum is also possible. Moreover, a hygroscopic compound can also be enclosed inside.

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

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

《Light extraction》
The organic EL element emits light inside a layer having a refractive index higher than that of air (refractive index is about 1.7 to 2.1) and can extract only about 15% to 20% of the light generated in the light emitting layer. It is generally said. This is because light incident on the interface (interface between the transparent substrate and air) at an angle θ greater than the critical angle causes total reflection and cannot be taken out of the device, or between the transparent electrode or light emitting layer and the transparent substrate. This is because the light is totally reflected between the light and the light is guided through the transparent electrode or the light emitting layer, and as a result, the light escapes in the direction of the element side surface.

  As a method for improving the light extraction efficiency, for example, a method of forming irregularities on the surface of the transparent substrate to prevent total reflection at the interface between the transparent substrate and the air (US Pat. No. 4,774,435), A method of improving efficiency by providing a light collecting property to a substrate (Japanese Patent Laid-Open No. 63-314795), a method of forming a reflective surface on a side surface of an element (Japanese Patent Laid-Open No. 1-220394), and light emission from a substrate A method of forming an antireflection film by introducing a flat layer having an intermediate refractive index between the bodies (Japanese Patent Laid-Open No. 62-172691), a flat having a lower refractive index between the substrate and the light emitter than the substrate A method of introducing a layer (Japanese Patent Laid-Open No. 2001-202827), a method of forming a diffraction grating between any one of a substrate, a transparent electrode layer and a light emitting layer (including between the substrate and the outside) (Japanese Patent Laid-Open No. 11-283951) Gazette).

  In the present invention, these methods can be used in combination with the organic EL device of the present invention. However, a method of introducing a flat layer having a lower refractive index than the substrate between the substrate and the light emitter, or a substrate, transparent A method of forming a diffraction grating between any layers of the electrode layer and the light emitting layer (including between the substrate and the outside) can be suitably used.

  In the present invention, by combining these means, it is possible to obtain an element having higher luminance or durability.

  When a medium having a low refractive index is formed between the transparent electrode and the transparent substrate with a thickness longer than the wavelength of light, the light extracted from the transparent electrode has a higher extraction efficiency to the outside as the refractive index of the medium is lower.

  Examples of the low refractive index layer include aerogel, porous silica, magnesium fluoride, and a fluorine-based polymer. Since the refractive index of the transparent substrate is generally about 1.5 to 1.7, the low refractive index layer preferably has a refractive index of about 1.5 or less. Further, it is preferably 1.35 or less.

  The thickness of the low refractive index medium is preferably at least twice the wavelength in the medium. This is because the effect of the low refractive index layer is diminished when the thickness of the low refractive index medium is about the wavelength of light and the electromagnetic wave that has exuded by evanescent enters the substrate.

  The method of introducing a diffraction grating into an interface or any medium that causes total reflection is characterized by a high effect of improving light extraction efficiency.

  This method uses the property that the diffraction grating can change the direction of light to a specific direction different from refraction by so-called Bragg diffraction such as first-order diffraction and second-order diffraction. Light that cannot be emitted due to total internal reflection between layers is diffracted by introducing a diffraction grating in any layer or medium (in a transparent substrate or transparent electrode), and the light is removed. I want to take it out.

  The introduced diffraction grating desirably has a two-dimensional periodic refractive index. This is because light emitted from the light-emitting layer is randomly generated in all directions, so in a general one-dimensional diffraction grating having a periodic refractive index distribution only in a certain direction, only light traveling in a specific direction is diffracted. Therefore, the light extraction efficiency does not increase so much.

  However, by making the refractive index distribution a two-dimensional distribution, light traveling in all directions is diffracted, and light extraction efficiency is increased.

  As described above, the position where the diffraction grating is introduced may be in any of the layers or in the medium (in the transparent substrate or in the transparent electrode), but is preferably in the vicinity of the organic light emitting layer where light is generated.

  At this time, the period of the diffraction grating is preferably about 1/2 to 3 times the wavelength of light in the medium.

  The arrangement of the diffraction grating is preferably two-dimensionally repeated such as a square lattice, a triangular lattice, or a honeycomb lattice.

<Condenser sheet>
The organic EL device of the present invention is processed to provide, for example, a microlens array-like structure on the light extraction side of the substrate, or in combination with a so-called condensing sheet, so that the organic EL device is in front of a specific direction, for example, the device light emitting surface. By condensing in the direction, the luminance in a specific direction can be increased.

  As an example of the microlens array, quadrangular pyramids having a side of 30 μm and an apex angle of 90 degrees are two-dimensionally arranged on the light extraction side of the substrate. One side is preferably 10 μm to 100 μm. If it becomes smaller than this, the effect of diffraction will generate | occur | produce and color, and if too large, thickness will become thick and is not preferable.

  As the condensing sheet, for example, a sheet that is put into practical use in an LED backlight of a liquid crystal display device can be used. As such a sheet, for example, a brightness enhancement film (BEF) manufactured by Sumitomo 3M Limited can be used. As the shape of the prism sheet, for example, the base material may be formed by forming a △ -shaped stripe having a vertex angle of 90 degrees and a pitch of 50 μm, or the vertex angle is rounded and the pitch is changed randomly. Other shapes may be used.

  Moreover, in order to control the light emission angle from a light emitting element, you may use together a light diffusing plate and a film with a condensing sheet. For example, a diffusion film (light-up) manufactured by Kimoto Co., Ltd. can be used.

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

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

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

  Examples of the method for forming each layer include a vapor deposition method and a wet process (also referred to as a coating method, such as a spin coating method, a casting method, an ink jet method, and a printing method) as described above. In the present invention, film formation by a wet process (coating method) such as a spin coating method, an ink jet method, or a printing method is preferable.

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

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

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

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

  In the organic EL element of the present invention, patterning may be performed by a metal mask, an ink jet printing method, or the like as needed during film formation. In the case of patterning, only the electrode may be patterned, the electrode and the light emitting layer may be patterned, or the entire layer of the device may be patterned. Can do.

  The light emission color of the organic EL device of the present invention and the compound according to the present invention is shown in FIG. 4.16 on page 108 of “New Color Science Handbook” (edited by the Japan Color Society, University of Tokyo Press, 1985). It is determined by the color when the result measured with the total CS-1000 (manufactured by Konica Minolta Sensing) is applied to the CIE chromaticity coordinates.

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

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

  The display device of the present invention may be single color or multicolor, but here, the multicolor display device will be described. In the case of a multicolor display device, a shadow mask is provided only at the time of forming a light emitting layer, and a film can be formed on one surface by 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 when a voltage of about 2 V to 40 V is applied 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》
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. 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 pixels 3 connected to the applied scanning line 5 emit light according to the image data signal.

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

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

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

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

  Next, a solution in which H-1 (60 mg) and Comparative 1 (3.0 mg) were dissolved in 6 ml of toluene was formed by spin coating under conditions of 1000 rpm and 30 seconds to provide a light emitting layer.

Subsequently, this substrate was fixed to a substrate holder of a vacuum deposition apparatus, 200 mg of BAlq was put into a molybdenum resistance heating boat, and attached to the vacuum deposition apparatus. After reducing the pressure of the vacuum chamber to 4 × 10 ⁻⁴ Pa, the heating boat containing BAlq is heated by heating, evaporated onto the light emitting layer at a deposition rate of 0.1 nm / second, and further an electron having a thickness of 40 nm. A transport layer was provided.

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

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

<< Production of Organic EL Elements 1-2 to 1-21 >>
In the production of the organic EL element 1-1, organic EL elements 1-2 to 1-21 were produced in the same manner except that the combination of the dopant compound and the host compound in the light emitting layer was changed to the combination shown in Table 1.

<< Evaluation of organic EL elements >>
When evaluating the obtained organic EL elements 1-1 to 1-21, 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 photo-curing adhesive (Lux Track LC0629B manufactured by Toagosei Co., Ltd.) is applied as a sealant around the periphery, and this is placed on the cathode so as to be in close contact with the transparent support substrate and irradiated with UV light from the glass substrate side. Then, it was cured and sealed, and an illumination device as shown in FIGS. 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).

  FIG. 6 is a cross-sectional view of the lighting device, 105 is a cathode, 106 is an organic EL layer, and 107 is 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 under a constant current condition of room temperature (about 23 to 25 ° C.) and ^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.

(Half life)
The half-life was evaluated according to the measurement method shown below.

Each organic EL device driven with a constant current at a current giving an initial luminance 1000 cd / ^{m 2,} obtains the time to be 1/2 (500cd / ^{m 2)} of the initial luminance, which was used as a measure of the half-life.

  The half-life was expressed as a relative value when the comparative organic EL element 1-1 was set to 100.

(Stillness stability of light emitting layer coating solution)
In the production of the organic EL element 1-1, the coating solution used for forming the light emitting layer (a solution in which a mixture of H-1 (60 mg) and Comparative 1 (3.0 mg) was dissolved in 12 ml of toluene) was stirred for 30 minutes at room temperature After standing, the presence or absence of precipitation was confirmed.

  The obtained results are shown in Table 1.

  From Table 1, it is clear that the organic EL device of the present invention exhibits high luminous efficiency and has a long lifetime as compared with the comparative organic EL device. Moreover, it turned out that precipitation of the organic EL element material by the coating liquid preparation used for formation of a light emitting layer is also improved.

Example 2
<< Preparation of Organic EL Element 2-1 >>
After patterning on a substrate (NA-45 manufactured by NH Techno Glass Co., Ltd.) formed by depositing 100 nm of ITO (indium tin oxide) on a 100 mm × 100 mm × 1.1 mm glass substrate as an anode, this ITO transparent electrode was provided. The transparent support substrate was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes.

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

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

  Next, using a solution obtained by dissolving Compound B (60 mg) and Comparative 1 (3.0 mg) in 6 ml of toluene, a film was formed by spin coating under conditions of 1000 rpm and 30 seconds. Irradiated with ultraviolet light for 15 seconds to cause photopolymerization / crosslinking, and further heated in vacuum at 150 ° C. for 1 hour to obtain a light emitting layer.

  Further, a solution of compound C (20 mg) dissolved in 6 ml of toluene was used to form a film by spin coating under conditions of 1000 rpm and 30 seconds. It was irradiated with ultraviolet light for 15 seconds to cause photopolymerization / crosslinking, and further heated in vacuum at 80 ° C. for 1 hour to form a hole blocking layer.

Subsequently, this substrate was fixed to a substrate holder of a vacuum vapor deposition apparatus, and 200 mg of Alq ₃ was put into a molybdenum resistance heating boat and attached to the vacuum vapor deposition apparatus. After reducing the vacuum chamber to 4 × 10 ⁻⁴ Pa, the heating boat containing Alq ₃ is energized and heated, and deposited on the hole blocking layer at a deposition rate of 0.1 nm / second to further form a film. An electron transport layer having a thickness of 40 nm was provided.

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

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

<< Production of Organic EL Elements 2-2 to 2-19 >>
In the production of the organic EL element 2-1, organic EL elements 2-2 to 2-19 were produced in the same manner except that the dopant compound and the host compound in the light emitting layer were changed to the combinations shown in Table 2.

<< Evaluation of organic EL elements >>
When evaluating the obtained organic EL elements 2-2 to 2-19, 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 photo-curing adhesive (Lux Track LC0629B manufactured by Toagosei Co., Ltd.) is applied as a sealant around the periphery, and this is placed on the cathode so as to be in close contact with the transparent support substrate and irradiated with UV light from the glass substrate side. Then, it was cured and sealed, and an illumination device as shown in FIGS. 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).

  FIG. 6 shows a cross-sectional view of the lighting device. In FIG. 4, 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 under a constant current condition of room temperature (about 23 ° C. to 25 ° C.) and ^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 2-1 being 100.

(Drive voltage)
The drive voltage is a voltage when driven at ^2.5 mA / cm ² , and the difference from the drive voltage (V) of the comparative organic EL element 2-1 was obtained.

Drive voltage (V) = Drive voltage (V) of organic EL element 2-1−Drive voltage (V) of organic EL element of the present invention
(Stillness stability of the light emitting layer coating solution (evaluation of precipitation))
In the production of the organic EL element 2-1, the coating solution used for forming the light emitting layer (a solution in which a mixture of Compound B (60 mg) and Comparative 1 (3.0 mg) was dissolved in 12 ml of toluene) was allowed to stand at room temperature for 30 minutes. Then, the presence or absence of precipitation was confirmed.

  The obtained results are shown in Table 2.

  From Table 2, it is clear that the organic EL device of the present invention exhibits high luminous efficiency and a low driving voltage as compared with the comparative organic EL device. Moreover, it turned out that precipitation of the organic EL element material by the coating liquid preparation used for formation of a light emitting layer is also improved.

Example 3
<< Preparation of white light emitting element and white lighting device >>
After patterning on a substrate (NA-45 manufactured by NH Techno Glass Co., Ltd.) formed by depositing 100 nm of ITO (indium tin oxide) on a 100 mm × 100 mm × 1.1 mm glass substrate as an anode, this ITO transparent electrode was provided. The transparent support substrate was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes.

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

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

  Next, using a solution obtained by dissolving Compound B (60 mg), Ir-14 (3.0 mg), and Compound 15 (3.0 mg) in 6 ml of toluene, a film was formed by a spin coating method at 1000 rpm for 30 seconds. . Irradiated with ultraviolet light for 15 seconds to cause photopolymerization / crosslinking, and further heated in vacuum at 150 ° C. for 1 hour to obtain a light emitting layer.

  Further, a solution of compound C (20 mg) dissolved in 6 ml of toluene was used to form a film by spin coating under conditions of 1000 rpm and 30 seconds. It was irradiated with ultraviolet light for 15 seconds to cause photopolymerization / crosslinking, and further heated in vacuum at 80 ° C. for 1 hour to form a hole blocking layer.

Subsequently, this substrate was fixed to a substrate holder of a vacuum vapor deposition apparatus, and 200 mg of Alq ₃ was put into a molybdenum resistance heating boat and attached to the vacuum vapor deposition apparatus. After reducing the pressure of the vacuum chamber to 4 × 10 ⁻⁴ Pa, the heating boat containing Alq ₃ was energized and heated, and deposited on the electron transport layer at a deposition rate of 0.1 nm / second to further form a film. An electron transport layer having a thickness of 40 nm was provided.

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

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

  When this element was energized, almost white light was obtained, and it was found that it could be used as a lighting device.

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 (19)

In an organic electroluminescence device having at least a light emitting layer sandwiched between an anode and a cathode,
The organic electroluminescent element characterized by containing the compound represented by following General formula (1).

[In formula, E1a-E1q represents a carbon atom or a nitrogen atom respectively. The skeleton composed of E1a to E1q has a total of 18π electrons. R1a to R1i each represents a hydrogen atom or a substituent. L01 and M1, has a site that each coupled between one covalent bond and one coordinate bond, and represents a partial structure having one-three metal atoms. n1 represents an integer of 1 or 2. M1 represents a group 8-10 transition metal element in the periodic table. ] The organic electroluminescence device according to claim 1, wherein L01 represents a partial structure represented by the following general formula (2).

[Wherein, E2a to E2e, E2l to E2q, and E2c ′ each represent a carbon atom or a nitrogen atom. The skeleton composed of E2a to E2e, E2l to E2q, and E2c ′ has 12π electrons in total. R2a, R2b, R2f, R2k, R2g to R2i, and R2c ′ each represent a hydrogen atom or a substituent. R2k and R2f may be connected to each other to form a ring. L02 represents a partial structure having at least two rings each bonded to each of M1 and M2 by one covalent bond and one coordination bond. n2 represents an integer of 1 or 2. n0 represents an integer of 0 or 1. M2 represents a transition metal element of Group 8 to Group 10 in the periodic table. ] The organic electroluminescence device according to claim 1 or 2, wherein the compound represented by the general formula (1) represents a compound represented by the following general formula (3).

[In formula, E1a-E1q represents a carbon atom or a nitrogen atom respectively. The skeleton composed of E1a to E1q has a total of 18π electrons. R1a to R1i each represents a hydrogen atom or a substituent. E2a to E2e, E2l to E2q, and E2c ′ each represent a carbon atom or a nitrogen atom. The skeleton composed of E2a to E2e, E2l to E2q, and E2c ′ has 12π electrons in total. R2a, R2b, R2f, R2k, R2g to R2i, and R2c ′ each represent a hydrogen atom or a substituent. R2k and R2f may be connected to each other to form a ring. L1 and L3 each represent a group having a site bonded to each of M1 and M2 by one covalent bond and one coordination bond, and having at least two rings as a partial structure; Represents a bond or a divalent to tetravalent linking group; n0 represents an integer of 0 or 1. n1 and n2 each represent an integer of 1 or 2. M1 and M2 each represent a group 8-10 group transition metal element in the periodic table. ] The compound represented by the general formula (3) is a compound represented by any one of the following general formulas (4), (5), or (6). Luminescence element.

[Wherein, E1a to E1q each represent a carbon atom or a nitrogen atom, and the skeleton composed of E1a to E1q has a total of 18π electrons. R1a to R1i each represents a hydrogen atom or a substituent. E2a to E2e, E2f to E2k, E2l to E2q, and E2c ′ each represent a carbon atom or a nitrogen atom.
The skeleton composed of E2a to E2e, the skeleton composed of E2a to E2e and E2c ′, the skeleton composed of E2f to E2k, and the skeleton composed of E2l to E2q each have 6π electrons. R2a, R2b, R2c, R2d, R2e, R2f, R2k, R2g to R2i, and R2c ′ each represent a hydrogen atom or a substituent. L1 and L3 each represent a group having a site bonded to each of M1 and M2 by one covalent bond and one coordination bond, and having at least two rings as a partial structure; Represents a bond or a divalent to tetravalent linking group; n1 and n2 each represent an integer of 1 or 2. M1 and M2 represent group 8 to group 10 transition metal elements in the periodic table. ] The skeleton composed of E1a to E1q of the compound represented by any one of the general formulas (4), (5), and (6) represents a partial structure represented by the following general formula (7) The organic electroluminescence device according to claim 4.

[In formula, E1b-E1e represents a carbon atom or a nitrogen atom respectively. R1a to R1i each represents a hydrogen atom or a substituent. n1 represents an integer of 1 or 2. M1 represents a group 8-10 transition metal element in the periodic table. * Represents a binding site. ] The organic electroluminescence device according to claim 5, wherein the partial structure represented by the general formula (7) represents a partial structure represented by the following general formula (8).

[Wherein, R1a to R1i each represents a hydrogen atom or a substituent. n1 represents an integer of 1 or 2. M1 represents a group 8-10 transition metal element in the periodic table. * Represents a binding site. ] The organic electroluminescence device according to claim 5, wherein the partial structure represented by the general formula (7) represents a partial structure represented by the following general formula (9).

[Wherein, R1a to R1i each represents a hydrogen atom or a substituent. n1 represents an integer of 1 or 2. M1 represents a group 8-10 transition metal element in the periodic table. * Represents a binding site. ] A partial structure represented by L01 according to claim 1, a partial structure represented by general formula (2) according to claim 2, M2, E2a to E2e in general formula (3) according to claim 3, E2l~E2q, E2c 'backbone comprised from the group consisting or formula according to claim 4, in (5), M2, E2a~E2e, E2l~E2q, E2c' skeletal comprised from the group consisting of 8 represents a partial structure represented by the following general formula (10), The organic electroluminescent element according to any one of claims 1 to 7.

[Wherein, E2b to E2e and E2c ′ each represent a carbon atom or a nitrogen atom. R2a, R2b, R2f, R2k, R2g to R2i, and R2c ′ each represent a hydrogen atom or a substituent. n2 represents an integer of 1 or 2. M2 represents a transition metal element of Group 8 to Group 10 in the periodic table. * Represents a binding site. ] A partial structure represented by L01 according to claim 1, a partial structure represented by general formula (2) according to claim 2, M2, E2a to E2e in general formula (3) according to claim 3, E2l～E2q, skeletal comprised from the group consisting of E2c 'or in the general formula (4) according to claim 4,, M2, E2a~E2e, either composed skeletal from the group consisting of E2l～E2q Has the partial structure represented by following General formula (11), The organic electroluminescent element of any one of Claims 1-7 characterized by the above-mentioned.

[Wherein, E2b to E2e each represent a carbon atom or a nitrogen atom. R2a, R2b, R2f, R2k, and R2g to R2i each represent a hydrogen atom or a substituent. n2 represents an integer of 1 or 2. M2 represents a transition metal element of Group 8 to Group 10 in the periodic table. * Represents a binding site. ] A partial structure represented by L01 according to claim 1, a partial structure represented by general formula (2) according to claim 2, M2, E2a to E2e in general formula (3) according to claim 3, E2l～E2q, skeletal comprised from the group consisting of E2c ', was or in the general formula (6) according to claim 4, M2, is constructed E2a~E2e, E2f~E2k, from the group consisting of E2l～E2q The organic electroluminescent element according to any one of claims 1 to 7, wherein any one of the skeletons has a partial structure represented by the following general formula (12).

[Wherein, E2b to E2k each represent a carbon atom or a nitrogen atom. R2a to R2i each represents a hydrogen atom or a substituent. n2 represents an integer of 1 or 2. M2 represents a transition metal element of Group 8 to Group 10 in the periodic table. * Represents a binding site. ] The organic electroluminescent device according to claim 8, wherein the partial structure represented by the general formula (10) is a partial structure represented by the following general formula (13).

[Wherein, R2a, R2b, R2f, R2k, R2g to R2i, and R2c ′ each represent a hydrogen atom or a substituent. n2 represents an integer of 1 or 2. M2 represents a transition metal element of Group 8 to Group 10 in the periodic table. * Represents a binding site. ] The organic electroluminescence device according to claim 9, wherein the partial structure represented by the general formula (11) is a partial structure represented by the following general formula (14).

[Wherein, R2a, R2b, R2f, R2k, R2g to R2i each represents a hydrogen atom or a substituent. n2 represents an integer of 1 or 2. M2 represents a transition metal element of Group 8 to Group 10 in the periodic table. * Represents a binding site. ] The partial structure represented by the general formula (12) is a partial structure represented by the following general formula (15) or a partial structure represented by the following general formula (16). The organic electroluminescent element of description.

[Wherein, R2a to R2i each represents a hydrogen atom or a substituent. n2 represents an integer of 1 or 2. M2 represents a transition metal element of Group 8 to Group 10 in the periodic table. * Represents a binding site. ]   The layer containing at least one compound represented by any one of the general formulas (1) and (3) to (6) as a constituent layer is a light emitting layer. 2. The organic electroluminescence device according to item 1.   As a constituent layer, it has an organic layer containing at least one compound represented by any one of the general formulas (1) and (3) to (6), and the organic layer was formed using a wet process. The organic electroluminescent element according to claim 1, wherein the organic electroluminescent element is any one of the above.   The organic electroluminescent element according to claim 1, wherein each of M1 and M2 represents platinum or iridium.   In the organic electroluminescent element of any one of Claims 1-16, the compound represented by the said General formula (1) of Claim 1, and the said General formula (3) of Claim 3 An organic electroluminescent device material comprising at least one compound represented by any one of the compounds represented by the formula (4), (5), or (6): .   A display device comprising the organic electroluminescence element according to claim 1.   An illuminating device comprising the organic electroluminescence element according to claim 1.

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