JP5272608B2 - Organic electroluminescence element, display device, and lighting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic EL device material for emitting light with very short wavelength with a high efficiency of light emission, and with a long light emission life, and an EL lighting apparatus and a display device using the same. <P>SOLUTION: The organic EL device includes at least a layer of a light emitting layer sandwiched between a positive electrode and a negative electrode. The light emitting layer includes a compound containing at least an imidazole ring or an pyrazole ring as a partial structure. The compound includes at least a substitute having a formula shown by general formula (5) in a molecule. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

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

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

  Inorganic electroluminescent elements have been used as planar light sources, but an alternating high voltage is required to drive the light emitting elements.

  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.

  Moreover, the element which has an organic light emitting layer which doped 8-hydroxyquinoline aluminum complex as a host compound and a trace amount fluorescent substance to this, and the organic light emission which doped 8-quinoquinoline aluminum complex as a host compound and this to the quinacridone series pigment | dye Devices having layers are known.

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

  However, since the University of Princeton has reported on organic EL devices using phosphorescence emission from excited triplets (see, for example, Non-Patent Document 1), research on materials that exhibit phosphorescence at room temperature has become active ( For example, see Non-Patent Document 2 and Patent Document 1).

  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, many compounds have been synthesized and studied centering on heavy metal complexes such as iridium complexes (see, for example, Non-Patent Document 3).

  Moreover, in the above-mentioned nonpatent literature 2, examination using tris (2-phenylpyridine) iridium as a dopant is performed.

In addition, as a dopant, L ₂ Ir (acac), for example, (ppy) ₂ Ir (acac), tris (2- (p-tolyl) pyridine) iridium (Ir (ptpy) ₃ ), tris (benzo [h] Studies using quinoline) iridium (Ir (bzq) ₃ ) and the like are being conducted (note that these metal complexes are generally called orthometalated iridium complexes).

  Further, in Non-Patent Document 3 and the like, attempts have been made to form devices using various iridium complexes.

  Further, in order to obtain high luminous efficiency, a hole transporting compound is used as a host of the phosphorescent compound. Further, various electron transporting materials are used as phosphorescent compound hosts by doping them with a novel iridium complex.

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

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

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

  In addition, regarding wavelength shortening, introduction of an electron withdrawing group such as a fluorine atom, a trifluoromethyl group, a cyano group or the like into phenylpyridine as a substituent, and picolinic acid or a pyrazabole-based ligand as a ligand. It is known to introduce.

  However, with these ligands, the emission wavelength of the light-emitting material is shortened to achieve blue, and a high-efficiency device can be achieved. On the other hand, the light-emitting lifetime of the device is greatly deteriorated, so an improvement in the trade-off is required. It was.

  It is disclosed that a metal complex having phenylpyrazole as a ligand is a light emitting material having a short emission wavelength (see, for example, Patent Documents 2 and 3). Furthermore, a metal complex formed from a ligand having a partial structure in which a 6-membered ring is condensed to a 5-membered ring of phenylpyrazole is disclosed (for example, see Patent Documents 4 and 5). There is disclosure of metal complexes having a phenanthridine skeleton. (For example, refer to Patent Document 6).

  However, with the metal complexes described in the above-mentioned known documents, the external extraction quantum efficiency is not improved, and a practically sufficient improvement effect is not obtained for the light emission lifetime, and there is a need for improvement. Yes.

The problems of the prior art are listed below. Compared to conventional phosphorescent metal complexes, metal complexes with a phenanthridine skeleton are less likely to generate excitons due to recombination of charges on the metal complex, and the charge to the light-emitting layer may be reduced depending on the device configuration. If the injection is not controlled well, there is a problem that the light emission efficiency does not increase, and at the same time, the light emission lifetime of the light emitting element is not extended. (For example, see Patent Document 6)
As apparent from the above-mentioned patent documents, the use of various phenanthridine compounds is still insufficient in terms of lifetime and efficiency, and further improvement is necessary.
US Pat. No. 6,097,147 International Publication No. 2004/085450 Pamphlet JP 2005-53912 A JP 2006-28101 A US Pat. No. 7,147,937 US Patent No. 20070190359 M.M. A. Baldo et al. , Nature, 395, 151-154 (1998) M.M. A. Baldo et al. , Nature, 403, 17, 750-753 (2000) S. Lamansky et al. , J .; Am. Chem. Soc. 123, 4304 (2001)

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an organic electroluminescence element, an illuminating device, and a display that exhibit specific short-wave emission, exhibit high emission efficiency, and have a long emission lifetime. Is to provide a device.

  In particular, it is to provide an organic electroluminescence device that exhibits high luminous efficiency with a short-wave light emission of blue to blue-green, has a low driving voltage, and has a long light emission lifetime.

The above object of the present invention can be achieved by the following configurations 1 to 14 .
Specifically, according to the present invention, in the constitution 1, in the general formulas (1) to (4), E ^{1a to} E ^{1e form} a pyrazole ring, an imidazole ring, or an oxazole ring, and E ^{1f to} E ^1k represent furan. A ring, an imidazole ring, a thiophene ring, a benzene ring, or a pyridine ring, E ^{1l to} E ^1q form a furan ring, a thiophene ring, a pyrazole ring, a benzene ring, or a pyridine ring, and R ^{1 *} is each a hydrogen atom Represents a substituent containing an atom, a fluorine atom, a methyl group, a mesityl group, a xylyl group, a cyano group, a butylene group, or a 1,3 butadiene group, and in the general formula (5), R ₁ and R ₂ are each hydrogen. R ₃ represents a hydrogen atom, a fluorine atom, a methyl group, a trifluoromethyl group, an isobutenyl group, a vinyloxy group, a benzene ring, a carbazole ring, or di A substituent containing a benzofuran ring is represented, and m is 1.

  1. In an organic electroluminescence device including at least one light emitting layer sandwiched between an anode and a cathode, the light emitting layer is represented by the following general formula (1), (2), (3), or (4) A compound containing at least one compound containing a partial structure and containing a partial structure represented by the general formula (1), (2), (3), or (4) is represented by the following general formula (5). An organic electroluminescence device having one or more substituents per molecule.

[Represents ^wherein, E 1b ^{to E 1p} is a carbon atom, a nitrogen atom, an oxygen atom or a sulfur ^atom, skeletal composed of E 1a ^{to E 1q} have 18π electrons in total. E ^1a and E ^1q are different from each other and represent a carbon atom or a nitrogen atom. M represents a group 8-10 transition metal element in the periodic table. R ^{1 *} each represents a hydrogen atom or a substituent. However, when E ^{1 *} to which R ^{1 *} is bonded is an oxygen atom or a sulfur atom, R ^{1 *} does not exist. In addition, when E ^{1 *} to which R ^{1 *} is bonded is a nitrogen atom, R ^{1 *} may not exist. Here, * represents any of the characters b, c, g, h, i, j, m, n, and o. ]

[Wherein, R ₁ and R ₂ each represent a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or a heteroaryl group. R ₁ and R ₂ may be bonded to each other to form a ring. R ₃ represents a hydrogen atom or a substituent. A plurality of R ³ present in one molecule may be the same or different. A plurality of adjacent R ₃ may be bonded to each other to form a ring. m is an integer of 1-3. n is an integer of 0-5. * Indicates a binding site with another part of the molecule. ]
2. In the organic electroluminescence device containing at least one light emitting layer sandwiched between an anode and a cathode, the light emitting layer contains at least one compound containing a partial structure represented by the following general formula (6) or (7). And a compound containing a partial structure represented by the general formula (6) or (7) has one or more substituents represented by the following general formula (5) in one molecule. An organic electroluminescence element.

^Wherein, E ^2a ~E ^2k, the E 2m ^{to E 2o} represents a carbon atom or a nitrogen ^atom,, E ^2a ~E ^2k, the skeleton composed of E 2m ^{to E 2o} having 18π electrons in total. M represents a group 8-10 transition metal element in the periodic table. R ^{2 *} each represents a hydrogen atom or a substituent. In addition, when E ^{2 *} to which R ^{2 *} is bonded is a nitrogen atom, R ^{2 *} may not exist. Here, * represents any of the characters b, c, g, h, i, j, m, n, and o. ]

[Wherein, R ₁ and R ₂ each represent a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or a heteroaryl group. R ₁ and R ₂ may be bonded to each other to form a ring. R ₃ represents a hydrogen atom or a substituent. A plurality of R ³ present in one molecule may be the same or different. A plurality of adjacent R ₃ may be bonded to each other to form a ring. m is an integer of 1-3. n is an integer of 0-5. * Indicates a binding site with another part of the molecule. ]
3. At least one selected from the compounds containing the partial structures represented by the general formulas (1) to (4), (6) and (7) is a molecule of the substituent represented by the general formula (5). 2. The organic electroluminescence device as described in 1 or 2 above, wherein the organic electroluminescence device has two or more.

  4). As for the substituent represented by the general formula (5), at least one selected from the compounds containing the partial structures represented by the general formulas (1) to (4), (6) and (7) is a partial structure. The organic electroluminescence device according to any one of the above items 1 to 3, which has one or more per one.

  5. M of the said General formula (5) is 1, The organic electroluminescent element of any one of said 1-4 characterized by the above-mentioned.

6). The ring composed of E ^{1a to} E ^1e and the ring composed of (6) and (7) E ^{2a to} E ^2e in the general formulas (1) to (4) are an imidazole ring or a pyrazole ring. 6. The organic electroluminescence device according to any one of 1 to 5 above.

  7). The organic according to any one of 1 to 6 above, wherein M in the partial structure represented by the general formulas (1) to (4), (6) and (7) is platinum or iridium. Electroluminescence element.

  8). The light-emitting layer contains a carbazole derivative or a derivative having a ring structure in which at least one carbon atom of a hydrocarbon ring constituting the carbazole ring of the carbazole derivative is substituted with a nitrogen atom. Organic electroluminescent element of any one of these.

  9. As a constituent layer, it has an organic layer containing at least one compound containing a partial structure represented by any one of the general formulas (1) to (4), (6) or (7), and the organic layer 9. The organic electroluminescence element according to any one of 1 to 8, wherein is formed using a wet process.

  10. Of the substituents in the compound containing the partial structure represented by any one of the general formulas (1) to (4), (6), or (7), at least one is a polymerizable substituent. 10. The organic electroluminescence device according to any one of 1 to 9 above.

  11. The polymer contains at least one polymer having a partial structure including a partial structure represented by any one of the general formulas (1) to (4), (6), or (7). The organic electroluminescent element of any one of 1-10.

  12 The organic electroluminescence device according to any one of 1 to 11 above, which emits white light.

  13. A display device comprising the organic electroluminescence element according to any one of 1 to 12 above.

  14 An illumination device comprising the organic electroluminescence element according to any one of 1 to 12 above.

  According to the present invention, it was possible to provide an organic electroluminescence device that exhibits specific short-wave light emission, exhibits high light emission efficiency, has a low driving voltage, and has a long light emission lifetime.

  Further, as a result of the study by the inventors, the present invention was able to greatly reduce the initial deterioration at the start of element driving. Furthermore, the generation of dark spots in the light emitting device during device driving was successfully reduced, and a useful organic electroluminescence device could be provided.

  In addition, an illumination device and a display device using the element could be provided.

  The present invention will be described in more detail. In the organic electroluminescent element of this invention, the structure prescribed | regulated to any one of Claims 1-12 WHEREIN: The organic electroluminescent element which shows high luminous efficiency and has a long light emission lifetime, and illumination using this element A device and a display device could 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 was observed to emit light with a specific short wave, and the lifetime of the organic electroluminescence element of the present invention could be remarkably improved.

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

《Metal complex (also called metal complex compound)》
The metal complex (also referred to as a metal complex compound) according to the present invention will be 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 present inventors have further studied, and compounds (metal complexes, metals) in which a condensed ring as shown in the partial structure represented by any one of the general formulas (1) to (4) according to the present invention is introduced. In the case where a complex compound) is applied to a light emitting material, the present inventors have succeeded in developing a light emitting dopant having a small emission wavelength shift and a long lifetime at a desired emission wavelength.

  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.

  As for the waveform, sub-luminescence is seen on the long wave side, and a decrease in color purity has become a problem. As a result of various investigations, by introducing at least one substituent into the ligand moiety, association between molecules can be prevented, side-light emission on the long wave side can be suppressed, and the stability of the metal complex (metal complex compound). Was also found to improve.

  As a result of further investigation, the introduction of the specific substituent disclosed in the present invention promotes the generation of excitons by recombination of charges on the metal complex, and the charge to the light emitting layer can be reduced by a special device configuration. Even if the injection was not controlled, the light emission efficiency was improved, and at the same time, the light emission lifetime of the light emitting element could be extended.

  Furthermore, as an unexpected effect, the initial deterioration at the start of element driving can be greatly reduced, and further, the dark spot of the light emitting element has been successfully reduced to provide a useful organic EL element. I was able to do it.

  The transition metal complex compound containing the partial structure represented by any one of the general formulas (1) to (4) according to the present invention has a plurality of ligands depending on the valence of the transition metal element represented by M. The ligands may all be the same, or may have ligands each having a different structure.

  Here, the ligand is a portion obtained by removing the transition metal element M from the partial structure represented by any one of the general formulas (1) to (4).

(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 element of group 8-10 of the periodic table)
Formation of a compound (also referred to as a transition metal complex, metal complex, or metal complex compound) containing a partial structure represented by any one of the general formulas (1), (2), (3), or (4) according to the present invention As the metal used in the above, a transition metal element belonging to Group 8 to 10 of the periodic table (also simply referred to as a transition metal) is used. Among them, iridium and platinum are preferable transition metal elements.

(Contained layer of transition metal complex according to the present invention)
The transition metal complex compound-containing layer containing the partial structure represented by any one of the general formulas (1) to (4) according to the present invention is not particularly limited as long as it is a layer that transports charges (charge transport layer). However, a hole transport layer or a light emitting layer, a light emitting layer or an electron blocking layer is preferable, a light emitting layer or an electron blocking layer is more preferable, and a light emitting layer is particularly preferable.

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

  First, the partial structure represented by any of the general formulas (1) to (4) according to the present invention will be described.

<< Partial structure represented by any one of general formulas (1) to (4) >>
The partial structure represented by any one of the general formulas (1) to (4) according to the present invention will be described.

In the partial structure represented by any of the general formulas (1) to (4), the ring formed by E ^{1a to} E ^1e represents a 5-membered aromatic heterocycle, such as an oxazole ring, a thiazole ring, Examples include 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 a pyrazole ring and an imidazole ring are particularly preferable.

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

In the partial structure represented by any one of the general formulas (1) to (4), the ring formed by E ^{1f to} E ^1k is a 6-membered aromatic hydrocarbon ring or a 5-membered or 6-membered aromatic heterocycle. Represents a ring.

Examples of the 6-membered aromatic hydrocarbon ring formed by E ^{1f to} E ^1k include a benzene ring. Furthermore, you may have the substituent mentioned later.

Examples of the 5-membered or 6-membered aromatic heterocycle formed by E ^{1f to} E ^1k include a furan ring, a thiophene ring, an oxazole ring, a pyrrole ring, a pyridine ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring, and a triazine ring. Etc.

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

In the partial structure represented by any one of the general formulas (1) to (4), the ring formed by E ^{11 to} E ^1q is a 6-membered aromatic hydrocarbon ring or a 5-membered or 6-membered aromatic heterocycle. These rings represent the same meaning as the 6-membered aromatic hydrocarbon ring or 5-membered or 6-membered aromatic heterocycle formed by E ^{1f to} E ^1k , respectively.

In the partial structure represented by any one of the general formulas (1) to (4), each of the substituents represented by R ^{1a to} R ¹ⁱ includes an alkyl group (for example, a methyl group, an ethyl group, a propyl group, an isopropyl group). Group, tert-butyl group, pentyl group, hexyl group, octyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, etc.), cycloalkyl group (for example, cyclopentyl group, cyclohexyl group, etc.), alkenyl group (for example, vinyl) Group, allyl group, etc.), alkynyl group (for example, ethynyl group, propargyl group, etc.), aryl group (for example, phenyl group, p-chlorophenyl group, mesityl group, tolyl group, xylyl group, naphthyl group, anthryl group, azulenyl group) , Acenaphthenyl group, fluorenyl group, phenanthryl group, indenyl group, pyrenyl group, bif Nitryl group, etc.), heteroaryl groups (for example, pyridyl group, pyrimidinyl group, furyl group, pyrrolyl group, imidazolyl group, benzimidazolyl group, pyrazolyl group, pyrazinyl group, triazolyl group (for example, 1,2,4-triazole-1- Yl, 1,2,3-triazol-1-yl, etc.), oxazolyl, benzoxazolyl, thiazolyl, isoxazolyl, isothiazolyl, furazanyl, thienyl, quinolyl, benzofuryl, dibenzofuryl Group, benzothienyl group, dibenzothienyl group, indolyl group, carbazolyl group, carbolinyl group, diazacarbazolyl group (indicating that one of the carbon atoms constituting the carboline ring of the previous carbolinyl group is replaced by a nitrogen atom), Quinoxalinyl group, pyridazinyl group, triazini Group, quinazolinyl group, phthalazinyl group, etc.), heterocyclic group (eg, pyrrolidyl group, imidazolidyl group, morpholyl group, oxazolidyl group, etc.), alkoxy group (eg, methoxy group, ethoxy group, propyloxy group, pentyloxy group, hexyl) 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 (for example, cyclopentylthio group, cyclohexylthio group, etc.), arylthio group (for example, phenylthio group, naphtho group, etc.) Tilthio group etc.), alkoxycarbonyl group (eg methyloxycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, octyloxycarbonyl group, dodecyloxycarbonyl group etc.), aryloxycarbonyl group (eg phenyloxycarbonyl group, Naphthyloxycarbonyl group, etc.), sulfamoyl group (for example, aminosulfonyl group, methylaminosulfonyl group, dimethylaminosulfonyl group, butylaminosulfonyl group, hexylaminosulfonyl group, cyclohexylaminosulfonyl group, octylaminosulfonyl group, dodecylaminosulfonyl group) , Phenylaminosulfonyl group, naphthylaminosulfonyl group, 2-pyridylaminosulfonyl group, etc.), acyl group (for example, acetyl group, ethylcarbonyl group) Propylcarbonyl group, pentylcarbonyl group, cyclohexylcarbonyl group, octylcarbonyl group, 2-ethylhexylcarbonyl group, dodecylcarbonyl group, phenylcarbonyl group, naphthylcarbonyl group, pyridylcarbonyl group, etc.), acyloxy group (for example, acetyloxy group, ethyl group) Carbonyloxy group, butylcarbonyloxy group, octylcarbonyloxy group, dodecylcarbonyloxy group, phenylcarbonyloxy group, etc.), amide group (eg, methylcarbonylamino group, ethylcarbonylamino group, dimethylcarbonylamino group, propylcarbonylamino group) Pentylcarbonylamino group, cyclohexylcarbonylamino group, 2-ethylhexylcarbonylamino group, octylcarbonylamino group, dodecylcarbonyl Bonylamino group, phenylcarbonylamino group, naphthylcarbonylamino group, etc.), carbamoyl group (for example, aminocarbonyl group, methylaminocarbonyl group, dimethylaminocarbonyl group, propylaminocarbonyl group, pentylaminocarbonyl group, cyclohexylaminocarbonyl group, octyl) Aminocarbonyl 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.), Rufinyl group (for example, methylsulfinyl group, ethylsulfinyl group, butylsulfinyl group, cyclohexylsulfinyl group, 2-ethylhexylsulfinyl group, dodecylsulfinyl group, phenylsulfinyl group, naphthylsulfinyl group, 2-pyridylsulfinyl group, etc.), alkylsulfonyl group (For example, methylsulfonyl group, ethylsulfonyl group, butylsulfonyl group, cyclohexylsulfonyl group, 2-ethylhexylsulfonyl group, dodecylsulfonyl group, etc.), arylsulfonyl group or heteroarylsulfonyl group (for example, phenylsulfonyl group, naphthylsulfonyl group, 2-pyridylsulfonyl group, etc.), amino group (for example, amino group, ethylamino group, dimethylamino group, butylamino group, cyclopentylamino) , 2-ethylhexylamino group, dodecylamino group, anilino group, naphthylamino group, 2-pyridylamino group, etc.), halogen atom (for example, fluorine atom, chlorine atom, bromine atom etc.), fluorinated hydrocarbon group (for example, fluoro Methyl group, trifluoromethyl group, pentafluoroethyl group, pentafluorophenyl group, etc.), cyano group, nitro group, hydroxy group, mercapto group, silyl group (for example, trimethylsilyl group, triisopropylsilyl group, triphenylsilyl group, Phenyldiethylsilyl group, etc.) and phosphono groups. These substituents may be further substituted with the above substituents.

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

<Preferred metal complex structure>
As the transition metal complex compound containing a partial structure represented by the general formula (1), (2), (3), or (4) of the present invention, more preferred is the general formula (6) or (7). It is a transition metal complex compound containing the partial structure represented by these.

<< Partial structure represented by either general formula (6) or (7) >>
The partial structure represented by either general formula (6) or (7) according to the present invention will be described.

In the partial structure represented by either general formula (6) or (7), the ring formed by E ^{2a to} E ^2e represents a 5-membered aromatic heterocycle, such as an oxazole ring, a thiazole ring, Examples include 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 a pyrazole ring and an imidazole ring are particularly preferable.

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

In the partial structure represented by either general formula (6) or (7), the ring formed by E ^{2f to} E ^2k is a 6-membered aromatic hydrocarbon ring or a 5-membered or 6-membered aromatic heterocycle. Represents a ring.

Examples of the 6-membered aromatic hydrocarbon ring formed by E ^{2f to} E ^2k include a benzene ring. Furthermore, you may have a substituent.

Examples of the 5-membered or 6-membered aromatic heterocycle formed by E ^{2f to} E ^2k include a furan ring, a thiophene ring, an oxazole ring, a pyrrole ring, a pyridine ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring, and a triazine ring. Etc. Each of these rings may further have a substituent.

In the partial structure represented by either general formula (6) or (7), the ring formed by three carbon atoms and E ^{2m to} E ^2o is a 6-membered aromatic hydrocarbon ring or a 6-membered aromatic Represents a family heterocycle.

^Examples of the 6-membered aromatic hydrocarbon ring formed by three carbon atoms and E ^{2m to} E ^2o include a benzene ring. Furthermore, you may have a substituent.

^Examples of the 6-membered aromatic heterocycle formed by three carbon atoms and E ^{2m to} E ^2o include a pyridine ring, a pyridazine ring, a pyrimidine ring, and a triazine.

  Each of these rings may further have a substituent.

In the partial structure represented by either general formula (6) or (7), each of the substituents represented by R ^{2a to} R ²ⁱ is represented by any one of general formulas (1) to (4). In the partial structure, the same as those shown as the substituent can be mentioned.

<< Specific Substituents of the Present Invention >>
In the present invention, the substituent of the transition metal complex compound containing the partial structure represented by the general formula (1), (2), (3), or (4) is represented by the above general formula (5). The object of the invention can be achieved by having one or more substituents per molecule.

In the formula, R ₁ and R ₂ are each a hydrogen atom, an alkyl group (for example, methyl group, ethyl group, propyl group, isopropyl group, tert-butyl group, pentyl group, hexyl group, octyl group, dodecyl group, tridecyl group, Tetradecyl group, pentadecyl group, etc.), cycloalkyl group (for example, cyclopentyl group, cyclohexyl group, etc.), aryl group (for example, phenyl group, p-chlorophenyl group, mesityl group, tolyl group, xylyl group, naphthyl group, anthryl group, Azulenyl, acenaphthenyl, fluorenyl, phenanthryl, indenyl, pyrenyl, biphenylyl, etc., or heteroaryl groups (eg, pyridyl, pyrimidinyl, furyl, pyrrolyl, imidazolyl, benzoimidazolyl, pyrazolyl) , Pyrazinyl group, tria Ryl group (for example, 1,2,4-triazol-1-yl group, 1,2,3-triazol-1-yl group, etc.), oxazolyl group, benzoxazolyl group, thiazolyl group, isoxazolyl group, isothiazolyl group , Furazanyl group, thienyl group, quinolyl group, benzofuryl group, dibenzofuryl group, benzothienyl group, dibenzothienyl group, indolyl group, carbazolyl group, carbolinyl group, diazacarbazolyl group (which constitutes the carboline ring of the carbolinyl group) Represents one in which one of the carbon atoms is replaced by a nitrogen atom), quinoxalinyl group, pyridazinyl group, triazinyl group, quinazolinyl group, phthalazinyl group, and the like. R ₁ and R ₂ may be bonded to each other to form a ring.

R ₃ represents a hydrogen atom or a substituent. A plurality of R ₃ present in one molecule may be the same or different. A plurality of adjacent R ₃ may be bonded to each other to form a ring.

Examples of the substituent represented by R ₃ include the same substituents as those shown as the substituent in the partial structure represented by any one of the general formulas (1) to (4).

  m is an integer of 1-3. n is an integer of 0-5. * Indicates a binding site with another part of the molecule.

<Alkylene chain length>
When m is an integer of 4 or more, the effect of the present invention is obtained because the distance between the aromatic ring structure of the ligand of the metal complex and the aromatic ring of the substituent represented by the general formula (5) increases. This is not preferable because it is not different from those obtained by simply substituting an alkyl group.

  When m ≦ 3, the effect of the present invention can be confirmed, but preferably m ≦ 2, more preferably m = 1. In particular, at m = 1, in addition to the effects of the present invention, the sublimation property of the transition metal complex compound containing the partial structure represented by the general formula (1), (2), (3), or (4) Since the secondary effect of improving is also obtained, it is particularly preferable when an organic EL element is produced by vapor deposition.

<Number of substituents>
Transition metal containing a partial structure represented by the general formula (1) to (4), (6) or (7) by having one or more substituents represented by the general formula (5) in one molecule The generation of excitons by recombination of charges on the complex compound is promoted, and the light emission efficiency is improved without controlling the injection of charges into the light emitting layer by a special element configuration, etc. I was able to extend it.

  The transition metal complex compound containing the partial structure represented by the general formulas (1) to (4), (6) or (7) of the present invention includes a substituent represented by the general formula (5) in one molecule. The effect of the invention can be obtained by having one or more in the above, but a more effective embodiment is to have two or more substituents represented by the general formula (5) in one molecule.

  Furthermore, an effective embodiment is to have three or more substituents represented by the general formula (5) in one molecule, and in particular, the substituent represented by the general formula (5) It is preferable to have one or more of each partial structure represented by the formulas (1) to (4).

<Replacement position>
The substitution position of the substituent represented by the general formula (5) is preferably on the aromatic ring bonded to the metal M. ^That, E 1a ^{to E 1e} or ^E 2a ^{to E} aromatic 5-membered ring onto which is formed by ^{2e, or,} E 1l ^{to E 1q} or ^E 2m ^{to E} aromatic 5-membered ring or on the aromatic formed by ^2o It is on a 6-membered ring.

More preferably, it is on a 5-membered ring or a 6-membered ring formed by E ^{1l to} E ^1q or E ^{2m to} E ^2o .

  Although the example of the substituent represented by General formula (5) below is shown, this invention is not limited to these.

<< Polymerizable substituent >>
In the partial structure represented by any one of the general formulas (1) to (4), (6), or (7), the substituents represented by R ^{1a to} R ¹ⁱ and R ^{2a to} R ²ⁱ are as described above. In addition to the alkenyl group, it may have a polymerizable group such as a styryl group, an epoxy group, an oxetanyl group, an acrylic group, and a methacryl group.

  Furthermore, the compound represented by the partial structure represented by any one of the general formulas (1) to (4), (6) or (7) reacts with the polymerizable groups or with other polymerizable monomers. A polymer can be formed.

  When a plurality of partial structures are present in the polymer, the partial structures represented by any one of the general formulas (1) to (4), (6), or (7) may be the same or different.

<Method for Polymerizing Partial Structure Represented by any of General Formulas (1) to (4), (6) or (7)>
The polymer having a partial structure represented by any one of the general formulas (1) to (4), (6) or (7) is “Revised Polymer Synthesis Chemistry” Chemistry “Experimental Method for Polymer Synthesis” It can be synthesized using the method described in "Chemical Doujin" 4th edition Experimental Chemistry Course 28 "Polymer Synthesis" Maruzen et al.

  Preferable polymerization methods include 1) polycondensation, 2) radical polymerization, 3) ionic polymerization, 4) polyaddition, addition condensation, and the like, which can be used depending on the type of polymerizable group.

  The polymer having a partial structure represented by any one of the general formulas (1) to (4), (6) or (7) can be made into a homopolymer using the above method, and combined with a plurality of monomers. Copolymers can also be used.

  Hereinafter, specific examples of a compound (also referred to as a metal complex or a metal complex compound) including a partial structure represented by any one of the general formulas (1) to (4), (6), or (7) according to the present invention. Although shown, this invention is not limited to these.

  These metal complexes are described in, for example, Organic Letter, vol. 16, 2579-2581 (2001), Inorganic Chemistry, Vol. 30, No. 8, 1685-1687 (1991), J. Am. Am. Chem. Soc. , 123, 4304 (2001), Inorganic Chemistry, Vol. 40, No. 7, 1704-1711 (2001), Inorganic Chemistry, Vol. 41, No. 12, 3055-3066 (2002) , New Journal of Chemistry. 26, 1171 (2002), European Journal of Organic Chemistry, Vol. 4, pages 695-709 (2004), and further synthesized by applying methods such as references described in these documents. it can.

  Below, the synthesis example of a typical compound is shown.

Synthesis of Exemplary Compound A-84 Step 1: Synthesis of Phenanthridine-6-amine Derivative

  In a 500 ml three-headed flask, a solution of 55 g (250 mmol) of 3-bromobenzoic acid chloride in 150 ml of tetrahydrofuran was placed in a nitrogen atmosphere, cooled in a dry ice-acetone bath, and cooled to an internal temperature of -78 ° C. Into this, 140 ml of a phenylmagnesium bromide tetrahydrofuran solution (2 mol / l solution manufactured by Tokyo Chemical Industry Co., Ltd.) was added dropwise over 2 hours. After completion of the dropwise addition, the temperature was gradually raised to room temperature, and then reacted at room temperature for 3 hours. After adding 200 ml of water to the reaction solution to decompose excess phenylmagnesium bromide, the product was extracted with 300 ml of ethyl acetate. The crude oil obtained by concentrating the extract under reduced pressure was purified by silica gel column chromatography (hexane-methylene chloride = 4: 1) to obtain 65 g (quantitative) of 3-bromobenzophenone.

  93 g (0.7 mol) of aluminum chloride finely crushed under a nitrogen atmosphere was charged into a 2 L three-head flask, and then 1 L of tetrahydrofuran was added while cooling with ice water. . When sufficiently cooled, 65 g (250 mmol) of 3-bromobenzophenone was added, and 46 g (1.2 mol) of sodium borohydride was further added. The mixture was heated with sufficient stirring and reacted for 7 hours under reflux. The reaction was completed after confirming the disappearance of the raw materials by thin layer chromatography.

  After cooling the reaction solution to room temperature, 500 ml of water was gradually added to hydrolyze excess aluminum chloride and sodium borohydride. Since hydrogen gas was generated along with the decomposition, the decomposition was carried out slowly so that the contents did not blow out. When the decomposition was completed, a homogeneous solution was obtained, and the product was extracted with 1 L of ethyl acetate. The crude oil obtained by concentrating the extract under reduced pressure was purified by distillation under reduced pressure to obtain 42 g (68%) of 1-benzyl-3-bromobenzene.

  In a 1 L three-headed flask, a solution of 42 g (170 mmol) of 1-benzyl-3-bromobenzene in 200 ml of tetrahydrofuran was placed in a nitrogen atmosphere, cooled in a dry ice-acetone bath, and cooled to an internal temperature of -78 ° C.

  Into this, 120 ml of n-butyllithium hexane solution (1.6 mol / l solution manufactured by Tokyo Chemical Industry) was dropped over 1 hour. After completion of the dropwise addition, the internal temperature was raised to -15 ° C, and then cooled again in a dry ice-acetone bath to cool to an internal temperature of -78 ° C. To this, a solution of trimethyl borate 21 g (0.2 mol) in 100 ml of tetrahydrofuran was added dropwise over 30 minutes, and then reacted for 30 minutes. Furthermore, it heated up to room temperature and reacted at room temperature for 5 hours. Subsequently, 700 ml of 10% sulfuric acid aqueous solution was added to the reaction solution, and the reaction was performed at room temperature for 3 hours.

  Since the reaction solution had two layers, a solvent layer and an aqueous layer, the aqueous layer was removed, and then the solvent layer was washed with brine three times. The solvent layer was concentrated under reduced pressure to obtain 37.8 g of a crude product. The crude product was purified by column gel chromatography (hexane-ethyl acetate = 3: 1) to obtain 19.7 g of 3-benzyl-phenylboronic acid (yield 55%).

  1-Bromo-4-methyl-3-nitrobenzene 13.4 g (62 mmol), 3-benzyl-phenylboronic acid 19.7 g (93 mmol), tripotassium phosphate 40 g (186 mmol) in a 1 L three-head flask under nitrogen atmosphere And 3.5 g (3.1 mmol) of tetrakis (triphenylphosphine) palladium (0) were added, and 300 ml of dehydrated toluene was added and stirred. Heating was started as it was, and the mixture was reacted for 8 hours under reflux with sufficient stirring. The reaction was completed after confirming the disappearance of the raw materials by thin layer chromatography. 300 ml of ethyl acetate was added to the reaction solution to extract the product. The extract was concentrated under reduced pressure to obtain 32 g of a crude product. This crude product was purified by column gel chromatography (hexane-ethyl acetate = 4: 1) to obtain 15.7 g (83% yield) of 3'-benzyl-4-methyl-2-nitrobiphenyl.

  Into an Erlenmeyer flask for hydrogenation reaction, a solution of 15.7 g (52 mmol) of 3′-benzyl-4-methyl-2-nitrobiphenyl in 200 ml of methanol and 100 ml of tetrahydrofuran was added, and a highly active palladium carbon catalyst (palladium) was added. 2.4 g) (content 20%). A gas inlet / outlet connector was attached, and the air in the container was replaced with nitrogen. Subsequently, hydrogen gas was introduced and the inside of the container was replaced with hydrogen gas. The hydrogenation reaction was performed for 10 hours at room temperature while supplying hydrogen gas. The reaction was completed after confirming the disappearance of the raw materials by thin layer chromatography. The palladium carbon catalyst was filtered and removed from the reaction solution, and concentrated under reduced pressure to obtain 15 g of a crude product. The crude product was purified by column gel chromatography (hexane-tetrahydrofuran = 2: 1) to obtain 14.0 g (yield 99%) of 3'-benzyl-4-methylbiphenyl-2-amine.

  In a 500 ml three-headed flask, 14.0 g (51 mmol) of 3'-benzyl-4-methylbiphenyl-2-amine, 12 g (260 mmol) of formic acid, and 140 ml of toluene were added, and the reaction was continued for 2 hours under heating and reflux. The reaction was completed after confirming the disappearance of the raw materials by thin layer chromatography. The reaction solution was concentrated under reduced pressure, dissolved again in toluene, and concentrated under reduced pressure twice to remove excess formic acid and used as it was in the next reaction.

  N- (3'-benzyl-4-methylbiphenyl-2-yl) formamide, which is the product of the previous step, was placed in a 500 ml three-headed flask, and 160 g of polyphosphoric acid (high viscosity bowl) was added. After mounting the mechanical stirrer, heating was started, and the reaction was carried out for 4 hours while heating in a 140 ° C. oil bath with sufficient stirring. The reaction was completed after confirming the disappearance of the raw materials by thin layer chromatography. The reaction was poured into ice water and stirred until a homogeneous solution was obtained. The product was extracted from the homogeneous solution with methylene chloride (200 ml x 3).

  The extract was concentrated under reduced pressure to obtain 15 g of a crude product. The crude product was purified by column gel chromatography (hexane-ethyl acetate = 10: 1 to 4: 1) to obtain 6.8 g (yield 47%) of 9-benzyl-3-methyl-phenanthridine.

  6.8 g (24 mmol) of 9-benzyl-3-methyl-phenanthridine and 200 ml of xylene were placed in a 300 ml three-headed flask and stirred at room temperature for a while to obtain a uniform solution. To this, 9.4 g (240 mmol) of sodium amide was added, and heating was started. The mixture was reacted for 1.5 hours under reflux while heating in an oil bath at 170 ° C. with sufficient stirring. The reaction was completed after confirming the disappearance of the raw materials by thin layer chromatography. The reaction was poured into ice water and stirred for 30 minutes. The toluene layer was separated and concentrated under reduced pressure to obtain 8 g of crude crystals. The crude crystals were suspended in hot toluene, and the crystals were filtered when cooled to room temperature. After washing with hexane and drying by heating, 5.5 g (yield 77%) of 9-benzyl-3-methyl-phenanthridin-6-amine was obtained.

  Step 2: Synthesis of bromoacetaldehyde derivative

  In a 1 L three-head flask, under a nitrogen atmosphere, a solution of 53.8 g (270 mmol) of 2-bromo-1,3,5-trimethylbenzene in 200 ml of tetrahydrofuran was added, cooled in a dry ice-acetone bath, and cooled to an internal temperature of -78 ° C. did. Into this, 190 ml of a hexane solution of n-butyllithium (1.6N solution manufactured by Tokyo Chemical Industry) was dropped over 1 hour. After completion of the dropwise addition, the reaction was continued at −78 ° C. for 30 minutes. Into this, a solution of 40 g (540 mmol) of dehydrated dimethylformamide in 50 ml of tetrahydrofuran was added dropwise over 1 hour. After completion of the dropwise addition, the temperature was raised to room temperature and reacted at room temperature for 1 hour. 200 ml of water was poured into the reaction solution and stirred for 30 minutes. Since the reaction solution had two layers, a solvent layer and an aqueous layer, the aqueous layer was removed, and then the solvent layer was washed with brine three times. The solvent layer was concentrated under reduced pressure to obtain 40.0 g (quantitative) of 2,4,6-trimethyl-benzaldehyde crude product. This was directly used in the next reaction.

  In a 1 L three-headed flask, 75 g (0.22 mol) of methoxymethyl (triphenylphosphonium) chloride and 400 ml of dehydrated tetrahydrofuran are placed in a nitrogen atmosphere, cooled in a dry ice-acetone bath while suspended, to an internal temperature of -78 ° C. Cooled down. Into this, 140 ml of n-butyllithium hexane solution (1.6N solution manufactured by Tokyo Chemical Industry Co., Ltd.) was added dropwise over 2 hours. After completion of the dropwise addition, the internal temperature was raised to −0 ° C., and then cooled again in a dry ice-acetone bath to cool to an internal temperature of −78 ° C. Into this, 100 ml of tetrahydrofuran solution of 32.6 g (0.22 mol) of 2,4,6-trimethylbenzaldehyde was added dropwise over 2 hours. After completion of the dropwise addition, the temperature was raised to room temperature and reacted at room temperature for 3 hours. The reaction was completed after confirming the disappearance of the raw materials by thin layer chromatography. The reaction was poured into ice water and stirred for 30 minutes. The solvent layer was separated and concentrated under reduced pressure to obtain 98 g of a crude product. The crude product was dissolved by heating in 500 ml of hexane, and insoluble matter (triphenylphosphine oxide) was filtered and removed. The filtrate was concentrated and purified by column gel column chromatography (hexane-tetrahydrofuran = 10: 1) to obtain 38.8 g (quantitative) of 2- (2-methoxyvinyl) 2,4,6-trimethylbenzene.

  In a 500 ml three-headed flask, put 200 ml of ethylene glycol dimethyl ether solution of 38.8 g (0.22 mol) of 2- (2-methoxyvinyl) 2,4,6-trimethylbenzene and 50 ml of 18% hydrochloric acid aqueous solution in an oil bath at 140 ° C. The reaction was carried out for 3 hours under reflux with heating. The reaction was completed after confirming the disappearance of the raw materials by thin layer chromatography. After cooling the reaction solution to room temperature, 200 ml of ethyl acetate was added. Since there were two layers, the aqueous layer was separated, and then the solvent layer was washed with 10% carbonated water and brine. The solvent layer was concentrated under reduced pressure to obtain 32.1 g (90%) of 2-mesitylacetaldehyde. This was directly used in the next reaction.

  A solution of 3.24 g (20 mmol) of 2-mesitylacetaldehyde in 40 ml of dimethylformamide was placed in a 100 ml three-headed flask and cooled to an internal temperature of 5 ° C. with ice water. N-bromosuccinimide (3.56 g, 20 mmol) and p-toluenesulfonic acid monohydrate (7.6 g, 40 mmol) were sequentially added thereto. After completion of the addition, the temperature was raised to room temperature, and the reaction was allowed to proceed at room temperature for 4 hours. The reaction was completed after confirming the disappearance of the raw materials by thin layer chromatography. 200 ml of ethyl acetate was added to the reaction solution and dispersed at room temperature for 1 hour. Since it became two layers when it left still, the water layer was isolate | separated and then the solvent layer was washed with water twice. The solvent layer was concentrated under reduced pressure to obtain 5.05 g (quantitative) of a crude product. The crude product was purified by column gel chromatography (hexane-tetrahydrofuran = 10: 1) to obtain 4.7 g (yield 98%) of 2-bromo-2-mesitylacetaldehyde.

  Step 3: Synthesis of ligand

  In a 100 ml three-head flask, 9-benzyl-3-methyl-phenanthridine-6-amine 1.98 g (6.6 mmol) in toluene 50 ml, 2-bromo-2-mesitylacetaldehyde 2.41 g (10.0 mmol) Then, 1.01 g (10.0 mmol) of triethylamine was added and reacted for 3 hours under reflux with heating in an oil bath at 140 ° C. The reaction was completed after confirming the disappearance of the raw materials by thin layer chromatography.

  The reaction solution was filtered to remove insolubles, and then concentrated under reduced pressure until the volume was reduced to about half. The solution was purified by silica gel column chromatography (hexane-tetrahydrofuran = 10: 1 to 5: 1) to give 10-benzyl-3-mesityl-6-methyl-imidazo [1,2, f] phenanthridine 2.42 g. (Yield 82%) was obtained.

  Step 4: Synthesis of exemplary compound A-84

  Iridium chloride was added to a solution of 1.1 g (2.5 mmol) of 10-benzyl-3-mesityl-6-methyl-imidazo [1,2, f] phenanthridine in 12 ml of 2-ethoxyethanol under a nitrogen atmosphere. Trihydrate, 350 mg (1.0 mmol) and 4 ml of water were added and refluxed for 5 hours under a nitrogen atmosphere. The reaction solution was cooled, 15 ml of methanol was added, and the precipitated crystals were collected by filtration. The obtained crystals were further washed with methanol and dried to obtain 740 mg (yield 66%) of Complex A.

  Under a nitrogen atmosphere, Complex A, 740 mg (0.33 mmol) and sodium carbonate, 2.0 were suspended in 30 ml of 2-ethoxyethanol. To this suspension, 0.5 g (5.0 mmol) of acetylacetone was added and refluxed for 5 hours under a nitrogen atmosphere. After cooling the reaction solution, a solid substance was collected by filtration under reduced pressure. Subsequently, when sodium carbonate and inorganic salt were removed by washing with water, complex B was obtained as lemon yellow crystals. The obtained crystals were further washed with a methanol / water = 1/1 mixed solution, and after drying, 470 mg (yield 60%) of Complex B was obtained.

  In a nitrogen atmosphere, Complex B, 470 mg (0.4 mmol) and 10-benzyl-3-mesityl-6-methyl-imidazo [1,2, f] phenanthridine 530 mg (1.2 mmol) were added to 30 ml of ethylene glycol. Suspended in The reaction was carried out at a reaction temperature of 180 to 190 ° C. for 2 hours under a nitrogen atmosphere, and when the disappearance of the complex B was confirmed, the reaction was terminated. The reaction solution was cooled, 30 ml of methanol was added, and the precipitated crystals were collected by filtration. The obtained crystals were further washed with methanol and dried to obtain 560 mg (yield 93%) of a crude product. This crude product was dissolved in a small amount of hexane-tetrahydrofuran = 1: 1 and purified by silica gel column chromatography (hexane-tetrahydrofuran = 1: 1) to obtain 550 mg (yield 91%) of exemplary compound A-84. It was.

  It was confirmed by MASS and 1H-NMR that the purified compound was the target product.

1H-NMR (400 MHz, THF-d8)
(Chemical shift δ, peak shape, proton number): δ =
1.99 (s, 9H, _-CH 3 of mesityl group)
2.40 (s, 18H, _-CH 3 of mesityl group)
2.65 (s, 9H, —CH _{3 of} phenanthridine ring)
4.17 (m, 6H, benzyl group —CH ₂ —)
7.14 (d, 3H,> CH of imidazole ring)
7.2 to 7.3 (m, 15H,> CH of the benzene ring of the benzyl group)
7.33 (s, 3H,> CH of phenanthridine ring)
7.40 (s, 6H,> CH of the benzene ring of the mesityl group)
7.42 (s, 3H,> CH of phenanthridine ring)
7.47 (d, 3H,> CH of phenanthridine ring)
7.74 (s, 3H,> CH of phenanthridine ring)
8.58 (d, 3H,> CH of phenanthridine ring)
The PL emission maximum wavelength in the solution of Exemplified Compound A-84 measured using Hitachi F-4500 was 458 nm (T = 77K in 2-methyltetrahydrofuran) and 464 nm (room temperature in methylene chloride).

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

  For example, Exemplified Compound A-130 can be synthesized by the following synthesis route by changing the raw material of Step1. About the detail of a synthetic reaction, since the method shown by the synthesis example of exemplary compound A-84 can be referred, it abbreviate | omits for details.

  Step 1: Synthesis of phenanthridine-6-amine derivative

  Step 2: Synthesis of bromoacetaldehyde derivative

  Step 3: Synthesis of ligand

  Step 4: Synthesis of exemplary compound A-130

  Further, exemplary compound A-158 can be synthesized by changing the raw materials of Step 1 and Step 2 and by the synthetic route shown below. About the detail of a synthetic reaction, since the method shown by the synthesis example of exemplary compound A-84 can be referred, it abbreviate | omits for details.

  Step 1: Synthesis of phenanthridine-6-amine derivative

  Step 2: Synthesis of bromoacetaldehyde derivative

  Step 3: Synthesis of ligand

  Step 4: Synthesis of exemplary compound A-158

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

(I) Anode / light emitting layer / electron transport layer / cathode (ii) Anode / hole transport layer / light emitting layer / electron transport layer / cathode (iii) Anode / hole transport layer / light emitting layer / hole blocking layer / electron Transport layer / cathode (iv) Anode / hole transport layer / light emitting layer / hole blocking layer / electron transport layer / cathode buffer layer / cathode (v) Anode / anode buffer layer / hole transport layer / light emitting layer / hole Blocking layer / electron transport layer / cathode buffer layer / cathode In the organic EL device of the present invention, the blue light emitting layer preferably has a light emission maximum wavelength of 430 nm to 480 nm, and the green light emitting layer has a light emission maximum wavelength of 510 nm to 550 nm, The red light emitting layer is preferably a monochromatic light emitting layer having a light emission maximum wavelength in the range of 600 nm to 640 nm, and is preferably a display device using these. Alternatively, a white light emitting layer may be formed by laminating at least three light emitting layers. Further, a non-light emitting intermediate layer may be provided between the light emitting layers. The organic EL element of the present invention is preferably a white light emitting layer, and is preferably a lighting device using these.

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

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

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

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

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

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

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

  As a known host compound that may be used in combination, a compound that has a hole transporting ability and an electron transporting ability, prevents the emission of light from being increased in wavelength, and has a high Tg (glass transition temperature) is preferable.

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

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

(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.

  The compound used as the phosphorescent dopant according to the present invention is preferably a transition metal complex compound including a partial structure represented by any one of the general formulas (1) to (4) according to the present invention.

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

<< Injection layer: electron injection layer, hole injection layer >>
The injection layer is provided as necessary, and there are an electron injection layer and a hole injection layer, and as described above, 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, or diazacarbazole derivative (shown in which any one of the carbon atoms constituting the carboline ring of the carboline derivative is replaced by a nitrogen atom). It is preferable to contain.

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

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

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

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

  On the other hand, the electron blocking layer has a function of a hole transport layer in a broad sense, and is made of a material having a function of transporting holes while having a very small ability to transport electrons, and transporting electrons while transporting holes. By blocking, the recombination probability of electrons and holes can be improved.

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

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

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

  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, as well as 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 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.

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

  In addition, metal-free or metal phthalocyanine, or those having terminal ends substituted with an alkyl group or a sulfonic acid group can be preferably used as the electron transporting material. In addition, the distyrylpyrazine derivative exemplified as the material of the light emitting layer can also be used as an electron transport material, and an inorganic semiconductor such as n-type-Si, n-type-SiC, etc. as in the case of the hole injection layer and 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, the vacuum deposition method, sputtering method, reactive sputtering method, molecular beam epitaxy method, cluster ion beam method, ion plating method, plasma polymerization method, atmospheric pressure plasma weight A combination method, a plasma CVD method, a laser CVD method, a thermal CVD method, a coating method, and the like can be used, but an atmospheric pressure plasma polymerization method as described in JP-A-2004-68143 is particularly preferable.

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

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

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

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

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

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

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

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

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 method, ion plating method, plasma polymerization method, atmospheric pressure plasma A polymerization method, a plasma CVD method, a laser CVD method, a thermal CVD method, a coating method, or the like can be used.

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

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

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

《Light extraction》
The organic EL element emits light inside a layer having a refractive index higher than that of air (refractive index is about 1.7 to 2.1) and can extract only about 15% to 20% of the light generated in the light emitting layer. It is generally said. This is because light incident on the interface (interface between the transparent substrate and air) at an angle θ greater than the critical angle causes total reflection and cannot be 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 on the light extraction side of the substrate so as to provide, for example, a microlens array structure, or combined with a so-called condensing sheet, for example, with respect to a specific direction, for example, the device light emitting surface. By condensing in the front direction, the luminance in a specific direction can be increased.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

This transparent support substrate was fixed to a substrate holder of a commercially available vacuum deposition apparatus, while 200 mg of α-NPD was put in a molybdenum resistance heating boat, and 200 mg of H-1 as a host compound was put in another molybdenum resistance heating boat, 200 mg of BAlq is put into another molybdenum resistance heating boat, 100 mg of FIrpic (IR-12) is put into another resistance heating boat made of molybdenum, and 200 mg of Alq ₃ is put into another resistance heating boat made of molybdenum. Installed.

Next, after reducing the vacuum chamber to 4 × 10 ⁻⁴ Pa, the heating boat containing α-NPD was heated by heating, and deposited on the transparent support substrate at a deposition rate of 0.1 nm / sec. The hole transport layer was provided.

  Further, the heating boat containing H-1 and FIrpic (Ir-12) is energized and heated, and co-deposited on the hole transport layer at a deposition rate of 0.2 nm / second and 0.012 nm / second, respectively. Thus, a light emitting layer having a thickness of 40 nm was provided. In addition, the substrate temperature at the time of vapor deposition was room temperature.

  Further, the heating boat containing BAlq was energized and heated, and was deposited on the light emitting layer at a deposition rate of 0.1 nm / second to provide a 10 nm thick hole blocking layer.

In addition, the heating boat containing Alq ₃ is further energized and heated, and deposited on the hole blocking layer at a deposition rate of 0.1 nm / second to further provide an electron transport layer having a thickness of 40 nm. It was. In addition, the substrate temperature at the time of vapor deposition was room temperature.

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

<< Production of Organic EL Elements 1-2 to 1-21 >>
In the production of the organic EL element 1-1, the organic EL element 1 was similarly prepared except that H-1 as the host compound of the light emitting layer and FIrpic (Ir-12) as the dopant compound were replaced with the compounds shown in Table 1. -2 to 1-21 were produced.

<< 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. 3 and 4 was formed and evaluated.

  FIG. 3 is 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).

  4 shows a cross-sectional view of the lighting device. In FIG. 4, reference numeral 105 denotes a cathode, 106 denotes an organic EL layer, and 107 denotes a glass substrate with a transparent electrode. The glass cover 102 is filled with nitrogen gas 108 and a water catching agent 109 is provided.

(External quantum efficiency)
By lighting the organic EL element 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.

(Initial deterioration)
The initial deterioration was evaluated according to the measurement method shown below. When the half-life was measured, the time required for the luminance to reach 90% was measured and used as a measure of initial deterioration. The initial deterioration was 100 for the comparative organic EL element 1-1. The initial deterioration was calculated based on the following formula.
Initial deterioration = (luminance 90% arrival time of organic EL element 1-1) / (luminance 90% arrival time of each element) × 100
That is, the smaller the initial deterioration value is, the smaller the initial deterioration is.

(Dark spot)
The light emitting surface when each organic EL element was continuously lit under a constant current condition of ^2.5 mA / cm ² at room temperature was visually evaluated. When the number of people who confirmed dark spots in each element after 10 hours of continuous lighting by visual evaluation by 10 randomly selected people was 5 or more ×
When the number of confirmed dark spots is 1-4
The case where the number of people who confirmed the dark spot was 0 was marked as “Good”.

  The above evaluation results are shown in Table 121.

  From Table 121, it can be seen that the organic EL device of the present invention has a higher external extraction quantum efficiency and less initial luminance deterioration, and has a longer lifetime as compared with the comparative device. It can also be seen that the generation of dark spots is suppressed.

Example 2
<Production of full-color display device>
(Production of blue light emitting element)
The organic EL element 1-14 of Example 1 was used as a blue light emitting element.

(Production of green light emitting element)
A green light emitting device was produced in the same manner as in the organic EL device 1-1 of Example 1 except that FIrpic (Ir-12) was changed to Ir-1, and this was used as a green light emitting device.

(Production of red light emitting element)
A red light emitting device was produced in the same manner as in the organic EL device 1-1 of Example 1 except that FIrpic (Ir-12) was changed to Ir-9, and this was used as a red light emitting device.

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

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

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

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

Example 3
<< Preparation of White Light Emitting Element and White Lighting Device-1 >>
The electrode of the transparent electrode substrate of Example 1 was patterned to 50 mm × 50 mm, and α-NPD was formed as a hole injection / transport layer with a thickness of 25 nm thereon as in Example 1, and further H— The heating boat containing 4 and the boat containing Exemplified Compound A-9 and the boat containing Ir-9 were energized independently, and H-4 as a luminescent host and Exemplified Compound A-9 as a luminescent dopant, In addition, the evaporation rate of Ir-9 was adjusted to be 100: 5: 0.6, vapor deposition was performed so as to have a thickness of 30 nm, and a light emitting layer was provided.

Next, 10 nm of BAlq was deposited to provide a hole blocking layer. Furthermore, it was deposited Alq ₃ at 40nm an electron transporting layer.

  Next, as in Example 1, a square perforated mask having the same shape as the transparent electrode made of stainless steel was placed on the electron transport layer, and lithium fluoride 0.5 nm as the cathode buffer layer and aluminum 150 nm as the cathode. Vapor deposition and film formation were performed.

  This element was provided with a sealing can having the same method and the same structure as in Example 1, and a flat lamp as shown in FIGS. 3 and 4 was produced. When this flat lamp was energized, almost white light was obtained, and it was found that it could be used as a lighting device.

Example 4
<< Production of White Light Emitting Element and White Lighting Device-2 >>
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 D 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 E (60 mg), R-8 (3.0 mg), and Ir-14 (3.0 mg) in 6 ml of toluene, a film is formed by spin coating under conditions of 1000 rpm and 30 seconds. did. Irradiated with ultraviolet light for 15 seconds to cause photopolymerization and crosslinking, and further heated in vacuum at 150 ° C. for 1 hour to obtain a light emitting layer.

  Furthermore, a film in which compound F (20 mg) was dissolved in 6 ml of toluene was used to form a film by spin coating under conditions of 1000 rpm and 30 seconds. Ultraviolet light was irradiated for 15 seconds, photopolymerization / crosslinking was performed, and further heating was performed 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 depressurizing the vacuum chamber to 4 × 10 ⁻⁴ Pa, energizing and heating the heating boat containing Alq ₃ , depositing on the hole blocking layer at a deposition rate of 0.1 nm / second, 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.

  This element was provided with a sealing can having the same method and the same structure as in Example 1, and a flat lamp as shown in FIGS. 3 and 4 was produced.

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

Example 5
<< Production of Organic EL Element 5-1 >>
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 D 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 prepared by dissolving Compound E (60 mg) and FIrpic (Ir-12) (3.0 mg) in 6 ml of toluene, a film is formed by spin coating at 1000 rpm for 30 seconds to form a light emitting layer. did.

  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 the vacuum chamber was depressurized to 4 × 10 ⁻⁴ Pa, the heating boat containing BAlq was energized and heated, deposited on the light emitting layer at a deposition rate of 0.1 nm / second, and a film thickness of 40 nm. The electron 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 organic EL element 5-1 was produced.

<< Production of Organic EL Elements 5-2 to 5-10 >>
In the production of the organic EL element 5-1, the organic EL element 5- was similarly prepared except that the compound E as the host compound of the light emitting layer and FIrpic (Ir-12) as the dopant compound were replaced with the compounds shown in Table 2. 2-5-10 were produced.

<< Evaluation of organic EL elements >>
When evaluating the obtained organic EL elements 5-1 to 5-10, 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. 3 and 4 was formed and evaluated.

  FIG. 3 is 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).

  4 shows a cross-sectional view of the lighting device. In FIG. 4, reference numeral 105 denotes a cathode, 106 denotes an organic EL layer, and 107 denotes a glass substrate with a transparent electrode. The glass cover 102 is filled with nitrogen gas 108 and a water catching agent 109 is provided.

(External quantum efficiency)
By lighting the organic EL element 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 5-1 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 with the comparative organic EL element 5-1 of Example 5 as 100.

(Initial deterioration)
The initial deterioration was evaluated according to the measurement method shown below. At the time of measuring the half-life, a time for 90% of the initial luminance was obtained and used as a measure of initial deterioration. In addition, initial stage deterioration was represented by the relative value which sets the comparison organic EL element 5-1 of Example 5 to 100. The initial deterioration was calculated based on the following formula.

Initial degradation = (90% reach time of luminance of organic EL element 5-1) / (90% reach time of brightness of each element) × 100
That is, the smaller the initial deterioration value is, the smaller the initial deterioration is.

(Dark spot)
The light emitting surface when the organic EL element was continuously lit under a constant current condition of ^2.5 mA / cm ² at room temperature was visually evaluated. When the number of people who confirmed dark spots by visual evaluation by 10 randomly selected people is 5 or more ×
When the number of confirmed dark spots is 1-4
The case where the number of people who confirmed the dark spot was 0 was marked as “Good”.

  The above evaluation results are shown in Table 2.

  From Table 122, it can be seen that the organic EL device of the present invention has a high external extraction quantum efficiency, little initial luminance deterioration, and a long life as a result, as compared with the comparative device. It can also be seen that the generation of dark spots is suppressed.

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

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Display 3 Pixel 5 Scan line 6 Data line A Display part B Control part 101 Organic EL element 107 Glass substrate with a transparent electrode 106 Organic EL layer 105 Cathode 102 Glass cover 108 Nitrogen gas 109 Water catching agent

Claims (14)

In an organic electroluminescence device including at least one light emitting layer sandwiched between an anode and a cathode, the light emitting layer is represented by the following general formula (1), (2), (3), or (4) A compound containing at least one compound containing a partial structure and containing a partial structure represented by the general formula (1), (2), (3), or (4) is represented by the following general formula (5). An organic electroluminescence device having one or more substituents per molecule.

[Represents ^wherein, E 1b ^{to E 1p} is a carbon atom, a nitrogen atom, an oxygen atom or a sulfur ^atom, skeletal composed of E 1a ^{to E 1q} have 18π electrons in total. E ^1a and E ^1q are different from each other and represent a carbon atom or a nitrogen atom. E ^1a to E ^1e is a pyrazole ring, to form an imidazole ring or oxazole ^ring,, E 1f ^{to E 1k} is a furan ring, an imidazole ring, a thiophene ring, form a benzene ring or a pyridine ^ring,, E 1l ^{to E 1q} is A furan ring, a thiophene ring, a pyrazole ring, a benzene ring, or a pyridine ring is formed. M represents a group 8-10 transition metal element in the periodic table. R ^{1 *} represents a substituent containing a hydrogen atom , a fluorine atom, a methyl group, a mesityl group, a xylyl group, a cyano group, a butylene group, or a 1,3 butadiene group . However, when E ^{1 *} to which R ^{1 *} is bonded is an oxygen atom or a sulfur atom, R ^{1 *} does not exist. In addition, when E ^{1 *} to which R ^{1 *} is bonded is a nitrogen atom, R ^{1 *} may not exist. Here, * represents any of the characters b, c, g, h, i, j, m, n, and o. ]

[Wherein, R ₁ and R ₂ each represents a hydrogen atom or a methyl group . R ₃ represents a substituent containing a hydrogen atom , a fluorine atom, a methyl group, a trifluoromethyl group, an isobutenyl group, a vinyloxy group, a benzene ring, a carbazole ring, or a dibenzofuran ring . A plurality of R ₃ present in one molecule may be the same or different . m is 1 . n is an integer of 0-5. * Indicates a binding site with another part of the molecule. ] In the organic electroluminescence device containing at least one light emitting layer sandwiched between an anode and a cathode, the light emitting layer contains at least one compound containing a partial structure represented by the following general formula (6) or (7). And a compound containing a partial structure represented by the general formula (6) or (7) has one or more substituents represented by the following general formula (5) in one molecule. An organic electroluminescence element.

Wherein, ^{E 2a} represents a nitrogen ^{atom, E 2} b ^~E 2k, the E 2m ^{to E 2o} represents a carbon atom or a nitrogen ^atom,, E ^2a ~E ^2k, skeletal composed of E 2m ^{to E 2o} Has a total of 18π electrons. E ^{2a to} E ^{2e form} a pyrazole ring or an imidazole ring, E ^{2f to} E ^2k form an imidazole ring, a benzene ring, or a pyridine ring, and E ^{2m to} E ^2o form a benzene ring or a pyridine ring. . M represents a group 8-10 transition metal element in the periodic table. R ^{2 *} each represents a hydrogen atom , a fluorine atom, a methyl group, a mesityl group, or a substituent containing a 1,3 butadiene group. In addition, when E ^{2 *} to which R ^{2 *} is bonded is a nitrogen atom, R ^{2 *} may not exist. Here, * represents any of the characters b, c, g, h, i, j, m, n, and o. ]

[Wherein, R ₁ and R ₂ each represents a hydrogen atom or a methyl group . R ₃ represents a substituent containing a hydrogen atom , a fluorine atom, a methyl group, a trifluoromethyl group, an isobutenyl group, a vinyloxy group, a carbazole ring, or a dibenzofuran ring . A plurality of R ₃ present in one molecule may be the same or different . m is 1 . n is an integer of 0-5. * Indicates a binding site with another part of the molecule. ] At least one selected from the compounds containing the partial structures represented by the general formulas (1) to (4), (6) and (7) is a molecule of the substituent represented by the general formula (5). The organic electroluminescence device according to claim 1, wherein two or more are contained in the organic electroluminescence device. As for the substituent represented by the general formula (5), at least one selected from the compounds containing the partial structures represented by the general formulas (1) to (4), (6) and (7) is a partial structure. The organic electroluminescent element according to claim 1, wherein one or more are provided per one. M of the said General formula (5) is 1, The organic electroluminescent element of any one of Claims 1-4 characterized by the above-mentioned. The ring composed of E ^{1a to} E ^1e and the ring composed of (6) and (7) E ^{2a to} E ^2e in the general formulas (1) to (4) are an imidazole ring or a pyrazole ring. The organic electroluminescence element according to claim 1, wherein the organic electroluminescence element is characterized in that 7. The partial structure represented by the general formulas (1) to (4), (6) and (7) is platinum or iridium, according to any one of claims 1 to 6. Organic electroluminescence device. The organic electroluminescent device according to claim 1, characterized in that it contains a carbazole derived material in the light emitting layer. As a constituent layer, it has an organic layer containing at least one compound containing a partial structure represented by any one of the general formulas (1) to (4), (6) or (7), and the organic layer The organic electroluminescence device according to claim 1, wherein the organic electroluminescence device is formed using a wet process. Of the substituents in the compound containing the partial structure represented by any one of the general formulas (1) to (4), (6), or (7), at least one is a polymerizable substituent. The organic electroluminescent element according to any one of claims 1 to 9. It contains at least one polymer having a partial structure of a compound including the partial structure represented by any one of the general formulas (1) to (4), (6), or (7). Item 11. The organic electroluminescence device according to any one of Items 1 to 10. The organic electroluminescence element according to claim 1, which emits white light. 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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