Organic electroluminescent element

Abstract

Provided are: an organic EL element having high efficiency and long life; and a compound suitable for the organic EL element. A compound represented by general formula (1), and an organic EL element using the same. Ar1 represents a general formula (2). R1 and R11 independently represent deuterium, an aliphatic hydrocarbon group having 1-10 carbon atoms, and an aromatic hydrocarbon group having 6-18 carbon atoms, a0 represents an integer of 0-3, s represents an integer of 0-3, and c represents an integer of 0-4. N and m are integers of 1-3, and at least one of n and m is 2 or 3. And * represents a bonding point with the general formula (1). X1 is N, or C-R2, and at least one X1 is N. And R2, Ar0, Ar2, and Ar3 independently represent hydrogen, deuterium, an aliphatic hydrocarbon group having 1-10 carbon atoms, an aromatic hydrocarbon group having 6-18 carbon atoms, or the like. # imgabs0 #

Description

Technical Field

[0001] The present invention relates to a compound, a material for an organic electroluminescent device, and an organic electroluminescent device (referred to as an organic EL device).

[0002] By applying a voltage to an organic electroluminescence (EL) device, holes are injected from an anode into a light-emitting layer, and electrons are injected from a cathode into the light-emitting layer. Further, in the light-emitting layer, the injected holes and electrons recombine to generate excitons. At this time, according to the statistical law of electron spin, singlet excitons and triplet excitons are generated in a ratio of 1:3. Regarding a fluorescent organic EL device that uses light emission generated by singlet excitons, it is considered that the limit of the internal quantum efficiency is 25%. On the other hand, it is known that in a phosphorescent organic EL device that uses light emission generated by triplet excitons, when intersystem crossing from singlet excitons is efficiently performed, the internal quantum efficiency is increased to 100%.

[0003] However, regarding phosphorescent organic EL devices, further extending the lifetime has become a technical issue.

[0004] Furthermore, recently, highly efficient organic EL devices using delayed fluorescence have been developed. For example, Patent Document 1 discloses an organic EL device that utilizes a triplet-triplet fusion (TTF) mechanism, which is one of the mechanisms of delayed fluorescence. The TTF mechanism utilizes the phenomenon that singlet excitons are generated by the collision of two triplet excitons, and it is considered that the internal quantum efficiency is theoretically increased to 40%. However, compared with phosphorescent organic EL devices, the efficiency is low, and thus further improvement in efficiency is required.

[0005] On the other hand, Patent Document 2 discloses an organic EL device that utilizes a thermally activated delayed fluorescence (TADF) mechanism. The TADF mechanism is a mechanism that utilizes the following phenomenon: in a material where the energy difference between the singlet energy level and the triplet energy level is small, reverse intersystem crossing from triplet excitons to singlet excitons occurs; it is considered that the internal quantum efficiency is theoretically increased to 100%. However, similar to phosphorescent devices, further improvement in lifetime characteristics is required, and in particular, improvement in lifetime characteristics is required for blue-emitting organic EL devices.

[0006] Prior Art Documents

[0007] Patent Documents

[0008] Patent Document 1: WO2010 / 134350 Gazette

[0009] Patent Document 2: WO2011 / 070963 Gazette

[0010] Patent Document 3: WO2015 / 102118 Gazette

[0011] Patent Document 4: WO2017 / 115833 Gazette

[0012] Patent Document 5: WO2018 / 212169 Gazette

[0013] Patent Document 6: WO2018 / 181188 Gazette

[0014] Patent Document 7: WO2020 / 040298 Gazette

[0015] Patent Document 8: Japanese Patent Laid-Open No. 2020-120096 Gazette

[0016] Patent Document 9: WO2016 / 159479 Gazette

[0017] Patent Document 10: US Published Specification No. 2011 / 0309345

[0018] Patent Document 11: WO2008 / 117826 Gazette

[0019] Patent Document 12: US Published Specification No. 2022 / 0177492

[0020] Patent Document 13: WO2016 / 158191 Gazette

[0021] Patent Document 14: WO2012 / 077520 Gazette

[0022] Patent Document 15: US Published Specification No. 2014 / 0158992

[0023] Patent Document 16: WO2016 / 158540 Gazette

[0024] Patent Document 17: US Published Specification No. 2020 / 0168812

[0025] There is disclosed in Patent Document 4 an organic EL element that contains, in a light-emitting layer, two host materials represented by the following compound and a TADF material as a light-emitting dopant.

[0026] [Chemical Formula 1]

[0027]

[0028] An organic EL element is disclosed in Patent Document 3 and Patent Document 5, which uses a TADF material containing a polycyclic aromatic compound represented by the following compound as a light-emitting dopant.

[0029] [Chemical formula 2]

[0030]

[0031] An organic EL element is disclosed in Patent Document 6 and Patent Document 7, which is used by mixing a boron compound, a TADF material, and the following carbazole compound a3 in a light-emitting layer.

[0032] [Chemical formula 3]

[0033]

[0034] An organic EL element is disclosed in Patent Document 8, which is used by mixing the following boron compound a7, a nitrogen-containing 6-membered ring compound a8, and a carbazole compound a9 in a light-emitting layer.

[0035] [Chemical formula 4]

[0036]

[0037] An organic EL element is disclosed in Patent Document 9, which uses a TADF material represented by the following compound as a light-emitting dopant.

[0038] [Chemical formula 5]

[0039]

[0040] A phosphorescent organic EL element is disclosed in Patent Document 10, which uses a compound formed by connecting a nitrogen-containing 6-membered ring represented by the following compound with a bi-carbazole or a tri-carbazole as a host material.

[0041] [Chemical formula 6]

[0042]

[0043] A phosphorescent organic EL element is disclosed in Patent Document 11, which uses a compound formed by connecting a nitrogen-containing 6-membered ring represented by the following compound with a carbazole as a host material.

[0044] [Chemical formula 7]

[0045]

[0046] A phosphorescent organic EL element is disclosed in Patent Document 12, which uses a compound formed by connecting a nitrogen-containing 6-membered ring represented by the following compound with a carbazole, or a deuterated compound thereof as a host material.

[0047] [Chemical Formula 8]

[0048]

[0049] In Patent Document 13, a phosphorescent organic EL element is disclosed, in which two host materials represented by the following compound and a phosphorescent material are contained as a light-emitting dopant in the light-emitting layer.

[0050] [Chemical Formula 9]

[0051]

[0052] In Patent Document 14, a phosphorescent organic EL element is disclosed, which uses a compound formed by linking a nitrogen-containing 6-membered ring represented by the following compound with biscarbazole as a host material.

[0053] [Chemical Formula 10]

[0054]

[0055] In Patent Document 15, an organic EL element is disclosed, which uses a TADF material represented by the following compound as a light-emitting dopant.

[0056] [Chemical Formula 11]

[0057]

[0058] In Patent Document 16, an organic EL element is disclosed, which is used by mixing a boron-based compound, a compound H1 or compound H2 formed by linking the following nitrogen-containing 6-membered ring and carbazole in the light-emitting layer.

[0059] [Chemical Formula 12]

[0060]

[0061] In Patent Document 17, an organic EL element is disclosed, which uses a compound H7 formed by linking the following nitrogen-containing 6-membered ring and carbazole.

[0062] [Chemical Formula 13]

[0063]

[0064] However, there is still room for improvement in any of the documents as an organic EL element showing sufficient lifetime characteristics. Summary of the Invention

[0065] Problems to be Solved by the Invention

[0066] In order to apply an organic EL element to a display element such as a flat panel display or a light source, it is necessary to improve the luminous efficiency of the element while sufficiently ensuring the stability during driving. An object of the present invention is to provide a practically useful organic EL element having characteristics of high efficiency and long life, and a compound suitable therefor.

[0067] Technical means for solving the problem

[0068] The present invention relates to a material for an organic electroluminescent element, which contains a compound represented by the following general formula (1).

[0069] [Chemical formula 14]

[0070]

[0071] Here, Ar 1 represents the following general formula (2).

[0072] [Chemical formula 15]

[0073]

[0074] R 1 independently represents deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, or a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms. R 11 independently represents hydrogen, deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, or a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms. a 0 represents the number of substitutions, and represents an integer of 0 to 3. s and c represent the number of substitutions. s independently represents an integer of 0 to 3, and c independently represents an integer of 0 to 4. n and m represent the number of repetitions, and independently represent an integer of 1 to 3, respectively. At least one of n or m represents 2 or 3. * represents the bonding point with the general formula (1).

[0075] X 1 independently represents N, or C-R 2 , and at least one X 1 represents N. R 2 independently represents hydrogen, deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to eight of the aromatic hydrocarbon groups.

[0076] Ar 2 and Ar 3represents hydrogen, a C1-C10 aliphatic hydrocarbon group, a substituted or unsubstituted C6-C18 aromatic hydrocarbon group, a substituted or unsubstituted C3-C17 aromatic heterocyclic group, or a substituted or unsubstituted linked aromatic group formed by linking two to eight of these aromatic groups.

[0077] Ar 0 represents deuterium, a C1-C10 aliphatic hydrocarbon group, a substituted or unsubstituted C6-C18 aromatic hydrocarbon group, a substituted or unsubstituted C3-C17 aromatic heterocyclic group, or a substituted or unsubstituted linked aromatic group formed by linking two to eight of these aromatic groups.

[0078] As a preferred form of the general formula (1), all X in the formula (1) 1 is N.

[0079] As a preferred form of the general formula (1), Ar in the formula (1) 1 contains at least one linked carbazolyl group represented by any one of the following general formulas (4a) to (4c).

[0080] [Chemical formula 16]

[0081]

[0082] Here, a and b represent the number of substituents. a independently represents an integer from 0 to 4, and b independently represents an integer from 0 to 3. ※ represents the bond node with the benzene ring of the general formula (2). In addition, R 1 and c have the same meaning as in the case of the general formula (2).

[0083] As a preferred form of the general formula (1), Ar in the formula (1) 1 is represented by any one of the following general formulas (5a) to (5e).

[0084] [Chemical formula 17]

[0085]

[0086] [Chemical formula 18]

[0087]

[0088] Here, R 1 , c, and * have the same meaning as in the case of the general formula (2). a and b have the same meaning as in the case of the general formulas (4a) to (4c).

[0089] As a preferred form of the general formula (1), Ar in the formula (1) 2 and Ar3 It is represented by hydrogen, deuterium, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to eight of the aromatic hydrocarbon groups.

[0090] As a preferred form of the general formula (1), it can be exemplified that the general formula (1) is represented by any one of the following general formulas (6a) to (6c).

[0091] [Chemical formula 19]

[0092]

[0093] Here, R 1 , and c have the same meanings as in the case of the general formula (2) and are independent of each other. In addition, a and b have the same meanings as in the case of the general formulas (4a) to (4c). In addition, f independently represents the number of substitutions and represents an integer from 0 to 5.

[0094] As a preferred form of the general formula (1), it can be exemplified that at least one of Ar 1 to Ar 3 contains deuterium atoms. As a further preferred form, it can be exemplified that at least one of Ar 2 and Ar 3 contains deuterium atoms.

[0095] As a preferred form of the general formula (1), it can be exemplified that at least one R 1 is deuterium.

[0096] The compound represented by the general formula (1) is preferably used as a material for an organic electroluminescent element.

[0097] In an organic electroluminescent element including one or more light-emitting layers between opposing anodes and cathodes, at least one light-emitting layer preferably contains: a host selected from the compounds represented by the general formula (1) and a light-emitting dopant. In addition, the light-emitting dopant is preferably a polycyclic aromatic compound represented by the following general formula (7a) or general formula (7b), or a phosphorescent light-emitting dopant.

[0098] [Chemical formula 20]

[0099]

[0100] Here, ring J, ring K, ring C, ring D, ring E, ring F, ring G, and ring H are each independently a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 24 carbon atoms, or a substituted or unsubstituted aromatic heterocycle having 3 to 17 carbon atoms.

[0101] Y 1Each independently is B, P, P=O, P=S, Al, Ga, As, Si-R 3 or Ge-R 3 , preferably B, P, P=O or P=S, more preferably B.

[0102] R 3 Each independently is an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms.

[0103] X 2 Each independently is O, N-Ar 4 , S or Se, preferably O, N-Ar 4 or S, more preferably O or N-Ar 4 .

[0104] Ar 4 Each independently is a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to eight of these.

[0105] N-Ar 4 Can be bonded to any one of ring J, ring K, ring C, ring D, ring E, ring F, ring G, or ring H to form a heterocycle containing N.

[0106] R 4 Each independently represents a cyano group, deuterium, a diarylamino group having 12 to 44 carbon atoms, an arylheteroarylamino group having 12 to 44 carbon atoms, a diheteroarylamino group having 12 to 44 carbon atoms, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms.

[0107] g and h represent the number of substituents, each independently representing an integer of 0 to 4, i and j represent the number of substituents, each independently representing an integer of 0 to 3, and k represents the number of substituents, representing an integer of 0 to 2.

[0108] As a preferred form of the polycyclic aromatic compound represented by the general formula (7a), a boron-containing polycyclic aromatic compound represented by the following formula (8a) can be cited, and as a preferred form of the polycyclic aromatic compound represented by the general formula (7b), a boron-containing polycyclic aromatic compound represented by the following formula (8b) can be cited.

[0109] [Chemical formula 21]

[0110]

[0111] Here, X3 Each independently represents N-Ar 4 , O, or S, provided that at least one X 3 represents N-Ar 4 . Ar 4 , R 4 , g, h, i, j, and k have the same meanings as in the case of the general formula (7a) or the general formula (7b).

[0112] The difference (ΔEST) between the singlet excitation energy (S1) and the triplet excitation energy (T1) of the polycyclic aromatic compound is preferably 0.20 eV or less, more preferably 0.10 eV or less.

[0113] The organic electroluminescent element of the present invention preferably contains a first host, a light-emitting dopant, and a second host selected from the compounds represented by the general formula (1), and more preferably contains a compound represented by the following general formula (9), or the general formula (12), or the general formula (13) as the second host. First, regarding the general formula (9), it is as follows.

[0114] [Chemical formula 22]

[0115]

[0116] Here, Z in the general formula (9) is a group containing an indolocarbazole ring represented by the general formula (10), and ** represents the bonding node with L 1 . Further, ring A in the general formula (10) is a heterocyclic ring represented by the general formula (11), and the ring A is condensed with the adjacent ring at an arbitrary position.

[0117] L 1 and L 2 are each independently a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms or a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms.

[0118] In addition, Ar 5 and Ar 6 are each independently deuterium, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to eight of these aromatic groups.

[0119] Furthermore, R 5 is independently deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms.

[0120] Furthermore, v represents the number of substituents, being an integer from 1 to 3, w represents the number of substituents, being an integer from 0 to 3, and q 1 and q 3 represent the number of substituents, each independently representing an integer from 0 to 4, and q 2 represents the number of substituents, being an integer from 0 to 2, and r represents the number of substituents, being an integer from 0 to 3.

[0121] General formula (9) can also be represented by the following general formula (9a) or general formula (9b).

[0122] [Chemical formula 23]

[0123]

[0124] Z, Ar 5 , v and w have the same meanings as in general formula (9), and X 4 represents O, or S. R 6 are each independently deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms.

[0125] Furthermore, regarding general formula (12) and general formula (13), it is as follows.

[0126] [Chemical formula 24]

[0127]

[0128] Here, Ar 7 , and Ar 8 each independently represent a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to eight aromatic rings of these aromatic groups.

[0129] R each independently represents deuterium, or an aliphatic hydrocarbon group having 1 to 10 carbon atoms.

[0130] e 1 ~e 4 represent the number of substituents, e 1 and e 4 independently represent integers from 0 to 4, and e 2 and e 3 independently represent integers from 0 to 3.

[0131] Furthermore, as another example, the organic electroluminescent element of the present invention preferably contains a compound represented by the following general formula (13) as the second host.

[0132] [Chemical formula 25]

[0133]

[0134] Here, Ar 9 represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to eight of these aromatic rings.

[0135] R 7 each independently represents deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms.

[0136] R 77 independently represents hydrogen, deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, or a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms.

[0137] t 1 ~t 4 each represents the number of substitutions, t 3 and t 4 each independently represents an integer of 0 to 4, t 1 and t 2 each independently represents an integer of 0 to 3. p represents the number of repetitions and independently represents an integer of 1 to 4, and u represents the number of substitutions and represents an integer of 1 or 2. When u is 2, the general formula (13) can be symmetric or asymmetric.

[0138] In addition, the first host and the second host in the present invention have mutually different structures.

[0139] Effects of the Invention

[0140] The organic EL element using the compound of the present invention can be an organic EL element with high luminous efficiency and long lifespan.

[0141] It is considered that the factors for the organic EL element of the present invention to achieve high luminous efficiency are as follows. Especially when the compound of the general formula (1) is used as the host, since the excitons generated on the host move rapidly to the light-emitting dopant, the energy loss is reduced; since the excitons generated on the light-emitting dopant are difficult to move to the host, the energy loss is small. In addition, the dicarbazole ring of the compound represented by the general formula (1) has the property of easily injecting holes, and the nitrogen-containing six-membered ring of the compound represented by the general formula (1) has the property of easily injecting electrons. Therefore, the balance of holes and electrons in the light-emitting layer can be maintained, and it is inferred that this situation is also a factor for high luminous efficiency. In addition, it is speculated that the factor for the organic EL element of the present invention to have a long life is that when a voltage is applied to the organic EL element, by preferentially injecting holes into the dicarbazole ring of the compound of the present invention represented by the general formula (1) and preferentially injecting electrons into the compound of the present invention containing the nitrogen-containing six-membered ring compound of the compound represented by the general formula (1), the electrochemical load on the light-emitting dopant is reduced. In addition, it is speculated that by using the compound represented by the general formula (9), general formula (12), or general formula (13) as the second host, the electrochemical load on the light-emitting dopant is further reduced.

[0142] In addition, the polycyclic aromatic compound represented by the general formula (7a) or general formula (7b), specifically the polycyclic aromatic compound represented by the general formula (8a) or general formula (8b), can emit blue light with high efficiency by utilizing the TADF mechanism. However, since the tolerance to holes and electrons is low, it is difficult to ensure the element life at a practical level in an element used in combination with a conventionally known host material. The compound represented by the general formula (1) of the present invention has higher tolerance to holes and electrons than these known compounds. Therefore, it can be an organic EL element with a longer life. BRIEF DESCRIPTION OF THE DRAWINGS

[0143] Figure 1 is a schematic cross-sectional view showing an example of an organic EL element. DETAILED DESCRIPTION OF THE INVENTION

[0144] The present invention relates to a compound represented by the general formula (1), and particularly to a substance in which the compound represented by the general formula (1) is used as a material for an organic electroluminescent element (organic EL element).

[0145] ​In addition, the organic EL element of the present invention has one or more light-emitting layers between the opposing anode and cathode, and at least one light-emitting layer contains a host selected from the compounds represented by the general formula (1) and a light-emitting dopant, preferably including a first host, a second host, and a light-emitting dopant selected from the compounds represented by the general formula (1). More preferably, the following is the case: a second host selected from the compounds represented by the general formula (9), the general formula (12), or the general formula (13) is contained, and in addition, a polycyclic aromatic compound represented by the general formula (7a) or general formula (7b), specifically, a polycyclic aromatic compound represented by the general formula (8a) or general formula (8b) is contained as the light-emitting dopant, or a phosphorescent light-emitting dopant is contained as the light-emitting dopant.

[0146] Regarding the present invention, first, the compound represented by the general formula (1) will be described.

[0147] In the general formula (1), Ar 1 represents the general formula (2). n and m represent the number of repetitions and each independently represents an integer of 1 to 3, provided that at least one of n or m represents 2 or 3. * represents the bonding point with the general formula (1).

[0148] R 1 independently represents deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, or a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms. Preferably, it is deuterium, an aliphatic hydrocarbon group having 1 to 8 carbon atoms, or a substituted or unsubstituted aromatic hydrocarbon group having 6 to 12 carbon atoms. More preferably, it is deuterium, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 10 carbon atoms.

[0149] When R 1 is an aliphatic hydrocarbon group having 1 to 10 carbon atoms, it can be any of a straight-chain, branched-chain, or cyclic aliphatic hydrocarbon group. As specific examples thereof, straight-chain saturated hydrocarbon groups such as methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-octyl, n-dodecyl, n-tetradecyl, and n-octadecyl, branched saturated hydrocarbon groups such as isopropyl, isobutyl, tert-butyl, neopentyl, 2-ethylhexyl, and 2-hexyloctyl, and saturated alicyclic hydrocarbon groups such as cyclopentyl, cyclohexyl, cyclooctyl, 4-butylcyclohexyl, and 4-dodecylcyclohexyl can be exemplified. Preferably, it is methyl, ethyl, n-propyl, n-butyl, tert-butyl, neopentyl, or cyclohexyl.

[0150] As specific examples of R 1 when it is an unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, those exemplified by benzene, naphthalene, acenaphthene, acenaphthylene, anthracene, Groups generated from pyrene, phenanthrene, triphenylene, fluorene, or benzo[a]anthracene, etc. Preferably, examples thereof include groups generated from benzene, naphthalene, anthracene, Groups generated from pyrene, phenanthrene, triphenylene, or fluorene. More preferably, examples thereof include groups generated from benzene or naphthalene.

[0151] s and c represent the number of substitutions. s independently represents an integer of 0 to 3, and c independently represents an integer of 0 to 4. s is preferably 0 to 2, and c is preferably 0 to 2. Among them, when R 1 is deuterium, s is preferably 2 to 3, and c is preferably 2 to 4.

[0152] R 11 independently represents hydrogen, deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, or a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms. Preferably, it is hydrogen, deuterium, an aliphatic hydrocarbon group having 1 to 8 carbon atoms, or a substituted or unsubstituted aromatic hydrocarbon group having 6 to 12 carbon atoms. More preferably, it is hydrogen, deuterium, or a substituted or unsubstituted aromatic hydrocarbon group having 6 to 10 carbon atoms.

[0153] As specific examples of when R 11 is an aliphatic hydrocarbon group having 1 to 10 carbon atoms and an unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, they are the same as the descriptions in the above R 1 respectively.

[0154] Among them, preferably, examples include methyl, ethyl, n-propyl, n-butyl, tert-butyl, neopentyl, or cyclohexyl, or groups generated from benzene, naphthalene, anthracene, pyrene, phenanthrene, triphenylene, or fluorene. More preferably, examples include groups generated from benzene and naphthalene.

[0155] Ar 0 represents deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to eight of these aromatic groups. Preferably, it represents deuterium, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 12 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to four of these aromatic rings. More preferably, it represents deuterium, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 10 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to three of these aromatic rings.

[0156] As specific examples of when Ar 0 is an aliphatic hydrocarbon group having 1 to 10 carbon atoms and an unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, they are the same as the descriptions in the above R 1 respectively.

[0157] Among them, preferred examples include methyl, ethyl, n-propyl, n-butyl, tert-butyl, neopentyl, or cyclohexyl, or a group derived from an aromatic hydrocarbon such as benzene, naphthalene, anthracene, pyrene, phenanthrene, triphenylene, or fluorene. More preferred examples include a group derived from benzene or naphthalene.

[0158] As Ar 0 Specific examples when it is an unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms may include groups derived from nitrogen-containing aromatic compounds having a pyrrole ring such as pyrrole, pyrrolopyrrole, indole, isoindole, pyrroloisoindole, carboline, thiophene, benzothiophene, dibenzothiophene, furan, benzofuran, dibenzofuran, carbazole, pyridine, pyrimidine, triazine, quinoline, isoquinoline, quinazoline, or quinoxaline, etc. Preferred are groups derived from thiophene, benzothiophene, dibenzothiophene, furan, benzofuran, dibenzofuran, or carbazole, and more preferred are groups derived from dibenzothiophene, dibenzofuran, or carbazole.

[0159] As Ar 0 Specific examples when it is an unsubstituted linked aromatic group may include groups formed by linking two to eight of the aromatic groups described in the specific examples when it is the unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms and the unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms.

[0160] a 0 represents the number of substitutions, which is an integer from 0 to 3, preferably 0 or 1. Among them, when Ar 0 is deuterium, a 0 is preferably 2 to 3.

[0161] X 1 independently represents N, or C-R 2 , and at least one X 1 represents N, and preferably all X 1 represent N.

[0162] R 2 independently represents hydrogen, deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to eight of the aromatic hydrocarbon groups. Preferred are hydrogen, deuterium, an aliphatic hydrocarbon group having 1 to 8 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 12 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to three of the aromatic hydrocarbon groups. More preferred are hydrogen, deuterium, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 10 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to three of the aromatic hydrocarbon groups.

[0163] As R 2Specific examples when it is an aliphatic hydrocarbon group having 1 to 10 carbon atoms or an unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms are the same as the description of the above-mentioned R respectively. 1 The description is the same as that in

[0164] Among them, preferred examples include methyl, ethyl, n-propyl, n-butyl, tert-butyl, neopentyl, or cyclohexyl, or an aromatic hydrocarbon group formed by removing a hydrogen atom from an aromatic hydrocarbon selected from benzene, naphthalene, anthracene, pyrene, phenanthrene, triphenylene, and fluorene. More preferred examples include groups formed from benzene and naphthalene.

[0165] R 2 Specific examples when it is an unsubstituted linked aromatic group include groups formed by linking two to eight of the aromatic groups described in the specific examples when it is an unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms.

[0166] Ar 2 and Ar 3 represent hydrogen, deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to eight of these aromatic groups. Preferably, it represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 12 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 6 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to four of these aromatic rings. More preferably, it represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 10 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to three of these aromatic rings.

[0167] As Ar 2 and Ar 3 Specific examples when it is an aliphatic hydrocarbon group having 1 to 10 carbon atoms or an unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms are the same as the description of the above-mentioned R respectively. 1 The description is the same as that in

[0168] Among them, preferred examples include methyl, ethyl, n-propyl, n-butyl, tert-butyl, neopentyl, or cyclohexyl, or a group formed from an aromatic hydrocarbon such as benzene, naphthalene, anthracene, pyrene, phenanthrene, triphenylene, or fluorene. More preferred examples include groups formed from benzene and naphthalene.

[0169] As Ar 2 and Ar 3 Specific examples when it is an unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms are the same as the description of the above-mentioned Ar 0 The description is the same as that in

[0170] Among them, preferably, groups derived from thiophene, benzothiophene, dibenzothiophene, furan, benzofuran, dibenzofuran, or carbazole can be enumerated. More preferably, groups derived from dibenzothiophene, dibenzofuran, or carbazole.

[0171] As Ar 2 and Ar 3 When it is an unsubstituted linking aromatic group, specific examples are the same as those of Ar 0 in the case of.

[0172] Ar 1 Preferably, it contains at least one linking carbazole structure represented by any one of the general formulas (4a) to (4c). a and b represent the number of substitutions. a independently represents an integer of 0 to 4, and b independently represents an integer of 0 to 3. a is preferably 0 to 3, and b is preferably 0 to 2. Among them, when R 1 is deuterium, a is preferably 2 to 4, and b is preferably 2 or 3. ※ represents the bond node with the benzene ring of the general formula (2).

[0173] In addition, Ar 1 is more preferably represented by any one of the general formulas (5a) to (5e).

[0174] The general formula (1) is preferably represented by any one of the general formulas (6a) to (6c). f in these formulas independently represents the number of substitutions and represents an integer of 0 to 5, and f is preferably 0 to 2. Among them, when R 1 is deuterium, f is preferably 2 to 5.

[0175] Preferably, at least one of Ar 1 to Ar 3 contains a deuterium atom, and more preferably at least one of Ar 2 and Ar 3 contains a deuterium atom. In addition, preferably at least one R 1 is deuterium.

[0176] The compound of the present invention is suitable as a material for an organic EL element. It is excellent as a host used in the light-emitting layer of an organic EL element, but can also be used for a hole blocking layer, a light-emitting material, etc. The organic EL element of the present invention contains a host selected from the compounds represented by the general formula (1) and a light-emitting dopant. In the organic EL element of the present invention, the compound represented by the general formula (7a) or the general formula (7b), which is suitably contained as a dopant in the light-emitting layer, will be described.

[0177] Ring J, ring K, ring C, ring D, ring E, ring F, ring G, and ring H are each independently a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 24 carbon atoms or a substituted or unsubstituted aromatic heterocyclic ring having 3 to 17 carbon atoms, preferably an aromatic hydrocarbon ring having 6 to 20 carbon atoms or an aromatic heterocyclic ring having 3 to 15 carbon atoms. Since ring J, ring K, ring C, ring D, ring E, ring F, ring G, and ring H are aromatic hydrocarbon rings or aromatic heterocyclic rings as described above, they are also referred to as aromatic rings.

[0178] Specific examples of the aromatic ring include those containing benzene, naphthalene, acenaphthene, acenaphthylene, azulene, anthracene, pyrene, phenanthrene, triphenylene, fluorene, benzo[a]anthracene pyridine, pyridine, pyrimidine, triazine, thiophene, isothiazole, thiazole, pyridazine, pyrrole, pyrazole, imidazole, triazole, thiadiazole, pyrazine, furan, isoxazole, quinoline, isoquinoline, quinoxaline, quinazoline, phthalazine, tetrazole, indole, benzofuran, benzothiophene, benzoxazole, benzothiazole, indazole, benzimidazole, benzotriazole, benzisothiazole, benzothiadiazole, purine, pyrone, coumarin, isocoumarin, chromone, dibenzofuran, dibenzothiophene, dibenzoselenophene, or carbazole. More preferably, it is a benzene ring, naphthalene ring, anthracene ring, triphenylene ring, phenanthrene ring, pyrene ring, pyridine ring, dibenzofuran ring, dibenzothiophene ring, or carbazole ring.

[0179] Y 1 are each independently B, P, P═O, P═S, Al, Ga, As, Si-R 3 or Ge-R 3 , preferably B, P, P═O or P═S, more preferably B.

[0180] R 3 are each independently an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, preferably an aliphatic hydrocarbon group having 1 to 8 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 12 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 15 carbon atoms. More preferably, it is a substituted or unsubstituted aromatic hydrocarbon group having 6 to 10 carbon atoms or a substituted or unsubstituted aromatic heterocyclic group having 3 to 12 carbon atoms.

[0181] As specific examples of when R 3 is an aliphatic hydrocarbon group having 1 to 10 carbon atoms and an unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, they are the same as the descriptions in the above-mentioned R 1 .

[0182] Among them, preferred examples include methyl, ethyl, n-propyl, n-butyl, tert-butyl, neopentyl, or cyclohexyl, or those derived from benzene, naphthalene, anthracene, A group derived from pyrene, phenanthrene, triphenylene, or fluorene. More preferably, examples include groups derived from benzene and naphthalene.

[0183] As R 3 When it is an unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, specific examples are the same as those described for the said Ar 0 in the description.

[0184] Among them, preferably, examples include groups derived from thiophene, benzothiophene, dibenzothiophene, furan, benzofuran, dibenzofuran, or carbazole. More preferably, examples include groups derived from dibenzothiophene, dibenzofuran, or carbazole.

[0185] X 2 are each independently O, N-Ar 4 , S or Se, preferably O, N-Ar 4 or S, more preferably O or N-Ar 4 .

[0186] Ar 4 are each independently a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to eight of these, preferably representing a substituted or unsubstituted aromatic hydrocarbon group having 6 to 12 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 15 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to six of the aromatic rings thereof. More preferably, it represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 10 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 12 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to four of the aromatic rings thereof. Even more preferably, it is a substituted or unsubstituted aromatic hydrocarbon group having 6 to 10 carbon atoms.

[0187] As Ar 4 When it is an unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, specific examples are the same as those described for the said R 1 in the description.

[0188] Among them, preferably, examples include groups derived from benzene, naphthalene, anthracene, pyrene, phenanthrene, triphenylene, or fluorene. More preferably, examples include groups derived from benzene and naphthalene.

[0189] As Ar 4 When it is an unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, specific examples are the same as those described for the said Ar 0 in the description.

[0190] Among them, preferably, groups derived from thiophene, benzothiophene, dibenzothiophene, furan, benzofuran, dibenzofuran, or carbazole can be enumerated. More preferably, groups derived from dibenzothiophene, dibenzofuran, or carbazole can be enumerated.

[0191] As Ar 4 Specific examples when it is an unsubstituted linking aromatic group are the same as those of Ar 0 in the case of.

[0192] N-Ar 4 can be bonded to any one of ring J, ring K, ring C, ring D, ring E, ring F, ring G, or ring H to form a heterocycle containing N.

[0193] R 4 Each independently represents a cyano group, deuterium, a diarylamino group having 12 to 44 carbon atoms, an arylheteroarylamino group having 12 to 44 carbon atoms, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms. Preferably, a diarylamino group having 12 to 36 carbon atoms, an arylheteroarylamino group having 12 to 36 carbon atoms, a diheteroarylamino group having 12 to 36 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 12 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 15 carbon atoms. More preferably, a diarylamino group having 12 to 24 carbon atoms, an arylheteroarylamino group having 12 to 24 carbon atoms, a diheteroarylamino group having 12 to 24 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 10 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 12 carbon atoms.

[0194] As R 4Specific examples of a diarylamino group having 12 to 44 carbon atoms, an arylheteroarylamino group having 12 to 44 carbon atoms, a diheteroarylamino group having 12 to 44 carbon atoms, and an aliphatic hydrocarbon group having 1 to 10 carbon atoms include: diphenylamino, dibiphenylamino, phenylbiphenylamino, naphthylphenylamino, dinaphthylamino, dianthrylamino, diphenanthrylamino, dipyrenylamino, dibenzofuranylphenylamino, dibenzofuranylbiphenylamino, dibenzofuranylnaphthylamino, dibenzofuranylanthrylamino, dibenzofuranylphenanthrylamino, dibenzofuranylpyranyl amino, bisdibenzofuranylamino, carbazolylphenylamino, carbazolylnaphthylamino, carbazolylanthrylamino, carbazolylphenanthrylamino, carbazolylpyranyl amino, dicarbazolylamino, methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl. Preferred examples include diphenylamino, dibiphenylamino, phenylbiphenylamino, naphthylphenylamino, dinaphthylamino, dianthrylamino, diphenanthrylamino, dipyrenylamino. More preferred examples include diphenylamino, dibiphenylamino, phenylbiphenylamino, naphthylphenylamino, dinaphthylamino, dibenzofuranylphenylamino, or carbazolylphenylamino.

[0195] As R 4 When it is an unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, it is the same as the description in the above R 1 above.

[0196] Among them, preferred examples include groups derived from benzene, naphthalene, anthracene, pyrene, phenanthrene, triphenylene, or fluorene. More preferred examples include phenyl and naphthyl.

[0197] As R 4 When it is an unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, it is the same as the description in the above Ar 0 above.

[0198] Among them, preferred examples include groups derived from thiophene, benzothiophene, dibenzothiophene, furan, benzofuran, dibenzofuran, or carbazole. More preferred examples include groups derived from dibenzothiophene, dibenzofuran, or carbazole.

[0199] g and h represent the number of substituents, and each independently represents an integer of 0 to 4, preferably an integer of 0 to 2, and more preferably 0 to 1. i and j represent the number of substituents, and each independently represents an integer of 0 to 3, preferably an integer of 0 to 2, and more preferably 0 to 1. k represents the number of substituents and represents an integer of 0 to 2, preferably 0 to 1.

[0200] As a preferred form of the polycyclic aromatic compound represented by the general formula (7a), a boron-containing polycyclic aromatic compound represented by the following formula (8a) can be cited. As a preferred form of the polycyclic aromatic compound represented by the general formula (7b), a boron-containing polycyclic aromatic compound represented by the following formula (8b) can be cited.

[0201] In the compounds represented by the general formula (8a) and the general formula (8b), X 3 each independently represents N-Ar 4 , O, or S, provided that at least one X 3 represents N-Ar 4 . In addition, the symbols common to the general formula (7a) or the general formula (7b) have the same meanings.

[0202] The organic EL element of the present invention may contain a compound represented by the general formula (9), the general formula (9a), the general formula (9b), the general formula (12), or the general formula (13) as a second host.

[0203] In the general formula (9), Z is a group containing an indolocarbazole ring represented by the general formula (10), and ** in the formula represents the bonding point with L 1 . In addition, ring A in the formula is a heterocyclic ring represented by the general formula (11), and ring A is condensed with an adjacent ring at an arbitrary position. Z is preferably a group containing an indolocarbazole ring represented by the following general formula (101).

[0204] [Chemical formula 26]

[0205]

[0206] ** in the formula (101) represents the bonding position with L 1 .

[0207] L 1 and L 2 are each independently a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms or a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, preferably a substituted or unsubstituted aromatic hydrocarbon group having 6 to 12 carbon atoms or a substituted or unsubstituted aromatic heterocyclic group having 3 to 15 carbon atoms. More preferably, they represent a substituted or unsubstituted aromatic hydrocarbon group having 6 to 10 carbon atoms or a substituted or unsubstituted aromatic heterocyclic group having 3 to 12 carbon atoms.

[0208] As specific examples when L 1 and L 2 are unsubstituted aromatic hydrocarbon groups having 6 to 18 carbon atoms, they are the same as the description in R 1 .

[0209] Among them, preferably, those that can be cited include benzene, naphthalene, anthracene, A group generated from pyrene, phenanthrene, triphenylene, or fluorene. More preferably, examples include groups generated from benzene and naphthalene. In addition, L 1 is v 1 +v 2 valent group, and L 2 is a (w + 1)-valent group.

[0210] As specific examples of when L 1 and L 2 are unsubstituted aromatic heterocyclic groups having 3 to 17 carbon atoms, they are the same as the description in the above Ar 0 .

[0211] Among them, preferred examples include groups generated from thiophene, benzothiophene, dibenzothiophene, furan, benzofuran, dibenzofuran, or carbazole. More preferably, examples include groups generated from dibenzothiophene, dibenzofuran, or carbazole.

[0212] Ar 5 and Ar 6 are each independently deuterium, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to eight of these aromatic groups. Preferably, they are a substituted or unsubstituted aromatic hydrocarbon group having 6 to 12 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 15 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to four of these. More preferably, they are a substituted or unsubstituted aromatic hydrocarbon group having 6 to 10 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 12 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to three of these. Further preferably, they are a substituted or unsubstituted aromatic hydrocarbon group having 6 to 10 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 12 carbon atoms.

[0213] As specific examples of when Ar 5 and Ar 6 are unsubstituted aromatic hydrocarbon groups having 6 to 18 carbon atoms, they are the same as the description in the above R 1 .

[0214] Among them, preferred examples include groups generated from benzene, naphthalene, anthracene, pyrene, phenanthrene, triphenylene, or fluorene. More preferably, examples include groups generated from benzene and naphthalene.

[0215] As specific examples of when Ar 5 and Ar 6 are unsubstituted aromatic heterocyclic groups having 3 to 17 carbon atoms, they are the same as the description in the above Ar 0 .

[0216] Among them, preferably, groups derived from thiophene, benzothiophene, dibenzothiophene, furan, benzofuran, dibenzofuran, or carbazole can be enumerated. More preferably, groups derived from dibenzothiophene, dibenzofuran, or carbazole can be enumerated.

[0217] As Ar 5 and Ar 6 When it is an unsubstituted linking aromatic group, specific examples are the same as those of the aforementioned Ar 0 case.

[0218] R 5 independently represents deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms. Preferably, it represents deuterium, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 12 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 15 carbon atoms. More preferably, it represents deuterium, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 10 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 12 carbon atoms.

[0219] As R 5 When it is an aliphatic hydrocarbon group having 1 to 10 carbon atoms and an unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, specific examples are the same as the descriptions in the aforementioned R 1 respectively.

[0220] Among them, preferably, methyl, ethyl, n-propyl, n-butyl, tert-butyl, neopentyl, or cyclohexyl, or groups derived from benzene, naphthalene, anthracene, pyrene, phenanthrene, triphenylene, or fluorene can be enumerated. More preferably, groups derived from benzene or naphthalene can be enumerated.

[0221] As R 5 When it is an unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, specific examples are the same as the descriptions in the aforementioned Ar 0 respectively.

[0222] Among them, preferably, groups derived from thiophene, benzothiophene, dibenzothiophene, furan, benzofuran, dibenzofuran, or carbazole can be enumerated. More preferably, groups derived from dibenzothiophene, dibenzofuran, or carbazole can be enumerated.

[0223] v represents the number of substitutions and represents an integer from 1 to 3, preferably represented by 1 or 2. w represents the number of substitutions and represents an integer from 0 to 3, preferably from 0 to 2. q 1 and q 3 represent the number of substitutions and independently represent integers from 0 to 4, preferably represented by integers from 0 to 2. q 2 represents the number of substitutions and represents an integer from 0 to 2, preferably represented by 0 or 1. r represents the number of substitutions and represents an integer from 0 to 3, preferably from 0 to 2.

[0224] The general formula (9) can be represented by the following general formula (9a) or general formula (9b), where X 4 represents O or S. In addition, the notations common to the general formula (9) have the same meanings.

[0225] R 6 are each independently deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, preferably deuterium, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 12 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 15 carbon atoms. More preferably, they are deuterium, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 10 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 12 carbon atoms.

[0226] As for R 6 When it is an aliphatic hydrocarbon group having 1 to 10 carbon atoms and an unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, the specific examples are the same as the descriptions of the respective R 1 above.

[0227] Among them, preferably, examples include methyl, ethyl, n-propyl, n-butyl, tert-butyl, neopentyl, cyclohexyl, or a group derived from benzene, naphthalene, anthracene, pyrene, phenanthrene, triphenylene, or fluorene. More preferably, examples include a group derived from benzene or naphthalene.

[0228] As for R 6 When it is an unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, the specific examples are the same as the descriptions of the respective Ar 0 above.

[0229] Among them, preferably, examples include a group derived from thiophene, benzothiophene, dibenzothiophene, furan, benzofuran, dibenzofuran, or carbazole. More preferably, examples include a group derived from dibenzothiophene, dibenzofuran, or carbazole.

[0230] Next, a compound represented by the general formula (12) that is suitably included as a second host in another example of the organic EL element of the present invention will be described. In addition, the general formula (12) is preferably represented by the following general formula (121).

[0231] [Chemical formula 27]

[0232]

[0233] Ar 7 and Ar 8Each independently represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to eight aromatic rings of these aromatic groups. Preferably, it is a substituted or unsubstituted aromatic hydrocarbon group having 6 to 12 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 15 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to four of these. More preferably, it is a substituted or unsubstituted aromatic hydrocarbon group having 6 to 10 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 12 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to three of these.

[0234] As Ar 7 and Ar 8 When it is a specific example of an unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, it is the same as the description in the above R 1 above.

[0235] Among them, preferably, groups derived from benzene, naphthalene, anthracene, pyrene, phenanthrene, triphenylene, or fluorene can be exemplified. More preferably, groups derived from benzene or naphthalene can be exemplified.

[0236] As Ar 7 and Ar 8 When it is a specific example of an unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, it is the same as the description in the above Ar 0 above.

[0237] Among them, preferably, groups derived from thiophene, benzothiophene, dibenzothiophene, furan, benzofuran, dibenzofuran, or carbazole can be exemplified. More preferably, groups derived from dibenzothiophene, dibenzofuran, or carbazole can be exemplified.

[0238] As Ar 7 and Ar 8 When it is a specific example of an unsubstituted linked aromatic group, it is the same as the case of Ar 0 above.

[0239] Each R independently represents deuterium or an aliphatic hydrocarbon group having 1 to 10 carbon atoms.

[0240] When it is a specific example of an aliphatic hydrocarbon group having 1 to 10 carbon atoms as R, it is the same as the description in the above R 1 above.

[0241] Among them, preferably, methyl, ethyl, n-propyl, n-butyl, tert-butyl, neopentyl, or cyclohexyl can be exemplified.

[0242] e 1 and e 4represents a substitution number, an integer from 0 to 4, preferably an integer from 0 to 2. e 2 and e 3 represents a substitution number, an integer from 0 to 3, preferably an integer from 0 to 2.

[0243] Next, the compound represented by the general formula (13), which is suitably included as a second host in the organic EL element of the present invention as another example, will be described.

[0244] Here, Ar 9 is a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to eight of these aromatic rings. Preferably, it is a substituted or unsubstituted aromatic hydrocarbon group having 6 to 12 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 6 to 15 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to four of these. More preferably, it is a substituted or unsubstituted aromatic hydrocarbon group having 6 to 10 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 6 to 12 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to three of these. Further preferably, it is a substituted or unsubstituted aromatic hydrocarbon group having 6 to 10 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to three of these.

[0245] As Ar 9 When it is an unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, the specific examples are the same as those described in the above for R 1 in.

[0246] Among them, preferably, groups derived from benzene, naphthalene, anthracene, pyrene, phenanthrene, triphenylene, or fluorene can be cited. More preferably, groups derived from benzene or naphthalene can be cited.

[0247] As Ar 9 When it is an unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, specific examples can include groups derived from benzothiophene, dibenzothiophene, benzofuran, dibenzofuran, carbazole, quinoline, isoquinoline, quinazoline, or quinoxaline. Preferably, groups derived from benzothiophene, dibenzothiophene, benzofuran, dibenzofuran, or carbazole, and more preferably, groups derived from dibenzothiophene, dibenzofuran, or carbazole.

[0248] As Ar 9 When it is an unsubstituted linked aromatic group, the specific examples are the same as those in the case of Ar 0 above.

[0249] R 7Each independently is deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, preferably deuterium, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 12 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 15 carbon atoms. More preferably, it is deuterium, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 10 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 12 carbon atoms.

[0250] As R 7 Specific examples when it is an aliphatic hydrocarbon group having 1 to 10 carbon atoms and an unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms are the same as the descriptions in the respective R 1 above.

[0251] Among them, preferably, examples include methyl, ethyl, n-propyl, n-butyl, tert-butyl, neopentyl, cyclohexyl, or a group derived from benzene, naphthalene, anthracene, pyrene, phenanthrene, triphenylene, or fluorene. More preferably, examples include a group derived from benzene or naphthalene.

[0252] As R 7 Specific examples when it is an unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms are the same as the descriptions in the respective Ar 0 above.

[0253] Among them, preferably, examples include a group derived from thiophene, benzothiophene, dibenzothiophene, furan, benzofuran, dibenzofuran, or carbazole. More preferably, examples include a group derived from dibenzothiophene, dibenzofuran, or carbazole.

[0254] R 77 Each independently represents hydrogen, deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, or a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms. Preferably, it is hydrogen, deuterium, an aliphatic hydrocarbon group having 1 to 8 carbon atoms, or a substituted or unsubstituted aromatic hydrocarbon group having 6 to 12 carbon atoms. More preferably, it is hydrogen, deuterium, or a substituted or unsubstituted aromatic hydrocarbon group having 6 to 10 carbon atoms.

[0255] As R 77 Specific examples when it is an aliphatic hydrocarbon group having 1 to 10 carbon atoms and an unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms are the same as the descriptions in the respective R 1 above.

[0256] Among them, preferably, examples include methyl, ethyl, n-propyl, n-butyl, tert-butyl, neopentyl, cyclohexyl, or a group derived from benzene, naphthalene, anthracene, pyrene, phenanthrene, triphenylene, or fluorene. More preferably, examples include a group derived from benzene or naphthalene.

[0257] t 3, and t 4 represents the substitution number, independently represents an integer from 0 to 4, preferably represented by an integer from 0 to 2, t 1 , and t 2 represents the substitution number, independently represents an integer from 0 to 3, preferably represented by an integer from 0 to 2, p represents the repetition number, independently represents an integer from 1 to 4, preferably represented by an integer from 1 to 2, u represents the substitution number, represents an integer of 1 or 2. When u is 2, the general formula (13) may be symmetric or asymmetric.

[0258] In the present specification, the linked aromatic group means a group in which the aromatic rings of an aromatic hydrocarbon group or an aromatic heterocyclic group are linked by a single bond, and these may be linked linearly or branched. In addition, the linked aromatic rings may be the same as or different from each other. When it conforms to the linked aromatic group, it is different from an aromatic hydrocarbon group having a substituent or an aromatic heterocyclic group having a substituent.

[0259] In the general formula (1), general formula (7a), general formula (7b), general formula (8a), general formula (8b), general formula (9), general formula (9a), general formula (9b), general formula (10), general formula (12) and formula (13), Ar 0 , Ar 2 ~Ar 9 , R 1 ~R 7 , R 11 , R 77 , R, L 1 , L 2 When they are an aromatic hydrocarbon group, an aromatic heterocyclic group or a linked aromatic group, these may have substituents. As the substituents, preferably deuterium, a cyano group, a triarylsilyl group having 18 to 36 carbon atoms, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a diarylamino group having 12 to 44 carbon atoms. Here, when the substituent is an aliphatic hydrocarbon group having 1 to 10 carbon atoms, it may be linear, branched, or cyclic. In addition, the number of substituents may be 0 to 5, preferably 0 to 2. In the calculation of the carbon number when the aromatic hydrocarbon group and the aromatic heterocyclic group have substituents, the carbon number of the substituents is not included. However, preferably, the total carbon number including the carbon number of the substituents satisfies the above range.

[0260] As specific examples of the substituents, examples include: deuterium, a cyano group, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a tert-butyl group, a pentyl group, a cyclopentyl group, a hexyl group, a cyclohexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, a diphenylamino group, a naphthylphenylamino group, a dinaphthylamino group, a dianthrylamino group, a diphenanthrylamino group, a dipyrenylamino group, a triphenylsilyl group. Preferably, examples include: deuterium, a cyano group, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a diphenylamino group, a naphthylphenylamino group, or a dinaphthylamino group.

[0261] In this specification, hydrogen is understood to be deuterium. That is, part or all of the hydrogen in the compounds represented by General Formula (1), General Formula (7a), General Formula (7b), General Formula (9), General Formula (9a), General Formula (9b), General Formula (12), and General Formula (13), or the hydrogen in the substituents, may be deuterium.

[0262] In addition, when explaining the average deuteration rate in the present invention, for example, it includes both the case of a single compound in the case of the compound represented by General Formula (1), and the case of a mixture of two or more compounds represented by General Formula (1). That is, when specifically explaining the average deuteration rate, when the average deuteration rate is 50%, it means that on average half of all the hydrogen is replaced by deuterium, and it may include a single compound or a mixture with different deuteration rates.

[0263] Specific examples of the compound represented by the above General Formula (1) are shown below, but are not limited to these exemplified compounds.

[0264] [Chemical Formula 28]

[0265]

[0266] [Chemical Formula 29]

[0267]

[0268] [Chemical Formula 30]

[0269]

[0270] [Chemical Formula 31]

[0271]

[0272] [Chemical Formula 32]

[0273]

[0274] [Chemical Formula 33]

[0275]

[0276] [Chemical Formula 34]

[0277]

[0278] [Chemical Formula 35]

[0279]

[0280] [Chemical Formula 36]

[0281]

[0282] [Chemical Formula 37]

[0283]

[0284] [Chemical Formula 38]

[0285]

[0286] [Chemical Formula 39]

[0287]

[0288] [Chemical Formula 40]

[0289]

[0290] [Chemical Formula 41]

[0291]

[0292] [Chemical Formula 42]

[0293]

[0294] [Chemical Formula 43]

[0295]

[0296] [Chemical Formula 44]

[0297]

[0298] [Chemical Formula 45]

[0299]

[0300] Specific examples of the compounds represented by the general formula (7a), general formula (7b), general formula (8a), or general formula (8b) are shown below, but are not limited to these exemplified compounds.

[0301] [Chemical Formula 46]

[0302]

[0303] [Chemical Formula 47]

[0304]

[0305] [Chemical Formula 48]

[0306]

[0307] [Chemical Formula 49]

[0308]

[0309] [Chemical 50]

[0310]

[0311] [Chemical 51]

[0312]

[0313] [Chemical 52]

[0314]

[0315] [Chemical 53]

[0316]

[0317] [Chemical 54]

[0318]

[0319] [Chemical 55]

[0320]

[0321] [Chemical 56]

[0322]

[0323] [Chemical 57]

[0324]

[0325] [Chemical 58]

[0326]

[0327] [Chemical 59]

[0328]

[0329] [Chemical 60]

[0330]

[0331] [Chemical 61]

[0332]

[0333] [Chemical 62]

[0334]

[0335] [Chemical 63]

[0336]

[0337] [Chemical 64]

[0338]

[0339] [Chemical Formula 65]

[0340]

[0341] [Chemical Formula 66]

[0342]

[0343] Specific examples of the compound represented by the general formula (9) are shown below, but are not limited to these exemplified compounds.

[0344] [Chemical Formula 67]

[0345]

[0346] [Chemical Formula 68]

[0347]

[0348] [Chemical Formula 69]

[0349]

[0350] [Chemical Formula 70]

[0351]

[0352] [Chemical Formula 71]

[0353]

[0354] [Chemical Formula 72]

[0355]

[0356] [Chemical Formula 73]

[0357]

[0358] [Chemical Formula 74]

[0359]

[0360] [Chemical Formula 75]

[0361]

[0362] [Chemical Formula 76]

[0363]

[0364] [Chemical Formula 77]

[0365]

[0366] [Chemical Formula 78]

[0367]

[0368] [Chemical Formula 79]

[0369]

[0370] [Chemical Formula 80]

[0371]

[0372] [Chemical Formula 81]

[0373]

[0374] [Chemical Formula 82]

[0375]

[0376] [Chemical Formula 83]

[0377]

[0378] [Chemical Formula 84]

[0379]

[0380] [Chemical Formula 85]

[0381]

[0382] [Chemical Formula 86]

[0383]

[0384] [Chemical Formula 87]

[0385]

[0386] [Chemical Formula 88]

[0387]

[0388] [Chemical Formula 89]

[0389]

[0390] [Chemical Formula 90]

[0391]

[0392] Specific examples of the compound represented by the general formula (12) are shown below, but are not limited to these exemplified compounds.

[0393] [Chemical Formula 91]

[0394]

[0395] [Chemical Formula 92]

[0396]

[0397] [Chemical Formula 93]

[0398]

[0399] [Chemical Formula 94]

[0400]

[0401] [Chemical Formula 95]

[0402]

[0403] [Chemical Formula 96]

[0404]

[0405] [Chemical Formula 97]

[0406]

[0407] [Chemical Formula 98]

[0408]

[0409] [Chemical Formula 99]

[0410]

[0411] Specific examples of the compound represented by the general formula (13) are shown below, but are not limited to these exemplified compounds.

[0412] [Chemical Formula 100]

[0413]

[0414] [Chemical Formula 101]

[0415]

[0416] [Chemical Formula 102]

[0417]

[0418] [Chemical Formula 103]

[0419]

[0420] [Chemical Formula 104]

[0421]

[0422] [Chemical Formula 105]

[0423]

[0424] [Chemical Formula 106]

[0425]

[0426] [Chemical Formula 107]

[0427]

[0428] [Chemical Formula 108]

[0429]

[0430] [Chemical Formula 109]

[0431]

[0432] [Chemical Formula 110]

[0433]

[0434] [Chemical Formula 111]

[0435]

[0436] [Chemical Formula 112]

[0437]

[0438] [Chemical Formula 113]

[0439]

[0440] [Chemical Formula 114]

[0441]

[0442] [Chemical Formula 115]

[0443]

[0444] [Chemical Formula 116]

[0445]

[0446] [Chemical Formula 117]

[0447]

[0448] [Chemical Formula 118]

[0449]

[0450] [Chemical 119]

[0451]

[0452] In the organic EL element of the present invention, the polycyclic aromatic compounds represented by the general formula (7a), general formula (7b), general formula (8a), and general formula (8b) used as the light-emitting dopant preferably have ΔEST of 0.20 eV or less. More preferably, it is 0.15 eV or less, and still more preferably, it is 0.10 eV or less.

[0453] ΔEST represents the difference between the singlet excitation energy (S1) and the triplet excitation energy (T1). Here, the measurement conditions of S1 and T1 are based on the method described in the examples.

[0454] By using a material selected from the polycyclic aromatic compounds represented by the general formula (7a), general formula (7b), general formula (8a), and general formula (8b) (hereinafter, also referred to as a polycyclic aromatic compound material) or a phosphorescent dopant as the light-emitting dopant, a material selected from the compounds represented by the general formula (1) as the first host, and a material selected from the compounds represented by the general formula (9), general formula (9a), general formula (9b), general formula (12), or general formula (13) as the second host, an excellent organic EL element can be provided.

[0455] Next, the structure of the organic EL element of the present invention will be described with reference to the drawings, but the structure of the organic EL element of the present invention is not limited thereto.

[0456] Figure 1 It is a cross-sectional view showing a structural example of a general organic EL element used in the present invention. 1 represents a substrate, 2 represents an anode, 3 represents a hole injection layer, 4 represents a hole transport layer, 5 represents a light-emitting layer, 6 represents an electron transport layer, and 7 represents a cathode. The organic EL element of the present invention may have an exciton blocking layer adjacent to the light-emitting layer, and may also have an electron blocking layer between the light-emitting layer and the hole injection layer. The exciton blocking layer can be inserted into either the anode side or the cathode side of the light-emitting layer, or can be inserted into both sides simultaneously. In the organic EL element of the present invention, an anode, a light-emitting layer, and a cathode are essential layers, but in addition to having the essential layers, a hole injection / transport layer and an electron injection / transport layer may also be provided, and further, a hole blocking layer may be provided between the light-emitting layer and the electron injection / transport layer. In addition, the hole injection / transport layer means either one or both of the hole injection layer and the hole transport layer, and the electron injection / transport layer means either one or both of the electron injection layer and the electron transport layer.

[0457] It can also beFigure 1 The reverse structure, i.e., the cathode 7, the electron transport layer 6, the light-emitting layer 5, the hole transport layer 4, the hole injection layer 3, and the anode 2 are sequentially stacked on the substrate 1. In such a case, layers can also be added or omitted as needed.

[0458] - Substrate -

[0459] The organic EL element of the present invention is preferably supported on a substrate. The substrate is not particularly limited as long as it is a substrate that has been used for organic EL elements in the past. For example, substrates including glass, transparent plastic, quartz, etc. can be used.

[0460] - Anode -

[0461] As the anode material in the organic EL element, materials including metals, alloys, conductive compounds, or mixtures thereof with a large work function (4 eV or more) can be preferably used. Specific examples of such electrode materials include: metals such as Au; conductive transparent materials such as CuI, Indium Tin Oxide (ITO), SnO2, ZnO. In addition, amorphous materials such as IDIXO (In2O3 - ZnO) that can form a transparent conductive film can also be used. The anode can use methods such as evaporation or sputtering to form a thin film of these electrode materials and use photolithography to form a pattern of the desired shape. Or when the pattern accuracy is not very required (about 100 μm or more), a mask of the desired shape can also be interposed during the evaporation or sputtering of the electrode materials to form a pattern. Or when using a material that can be coated such as an organic conductive compound, wet film-forming methods such as printing or coating can also be used. When light is emitted from the anode, it is desirable that the transmittance is greater than 10%. In addition, the sheet resistance of the anode is preferably several hundred Ω / Υ or less. The film thickness also depends on the material and is usually selected in the range of 10 nm to 1000 nm, preferably 10 nm to 200 nm.

[0462] - Cathode -

[0463] On the other hand, as the cathode material, a material containing a metal with a small work function (4 eV or less) (referred to as an electron-injecting metal), an alloy, a conductive compound, or a mixture thereof can be used. Specific examples of such electrode materials include: sodium, sodium-potassium alloy, magnesium, lithium, magnesium / copper mixture, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, aluminum / aluminum oxide (Al2O3) mixture, indium, lithium / aluminum mixture, rare earth metals, etc. Among these, in terms of electron injection property and durability against oxidation and the like, a mixture of an electron-injecting metal and a second metal which is a metal having a larger and more stable work function value than it is suitable, for example, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, aluminum / aluminum oxide (Al2O3) mixture, lithium / aluminum mixture, aluminum, etc. The cathode can be fabricated by forming a thin film of these cathode materials using a method such as evaporation or sputtering. In addition, as the cathode, the sheet resistance is preferably several hundred Ω / □ or less, and the film thickness is generally selected in the range of 10 nm to 5 μm, preferably 50 nm to 200 nm. Further, in order for the emitted light to pass through, it is appropriate if either the anode or the cathode of the organic EL element is transparent or translucent, as the luminous brightness is increased.

[0464] In addition, after forming the metal on the cathode with a film thickness of 1 nm to 20 nm, a conductive transparent material listed in the description of the anode is formed thereon, whereby a transparent or translucent cathode can be fabricated, and by applying the above method, an element in which both the anode and the cathode have permeability can be fabricated.

[0465] -Light-emitting layer-

[0466] The light-emitting layer is a layer that emits light after excitons are generated by the recombination of holes and electrons respectively injected from the anode and the cathode, and the light-emitting layer contains a light-emitting dopant and a host.

[0467] Regarding the light-emitting dopant and the host, for example, they can be used in such a manner that the light-emitting dopant is 0.10% to 10% and the host is 99.9% to 90%. Preferably, the light-emitting dopant is 1.0% to 5.0% and the host is 99% to 95%, and more preferably, the light-emitting dopant is 1.0% to 3.0% and the host is 99% to 97%.

[0468] In this specification, unless otherwise specified, % is mass %.

[0469] As the host in the light-emitting layer, the general formula (1) of the compound of the present invention can be used. Additionally, in the case of using the first host and the second host, the compound represented by the general formula (1) can be used as the first host, and the compound represented by the general formula (9), general formula (12), or general formula (13) can be suitably used as the second host. The first host and the second host can be used, for example, with the first host being 10% to 90% and the second host being 90% to 10%. Preferably, the first host is 30% to 70% and the second host is 70% to 30%, and more preferably, the first host is 30% to 50% and the second host is 70% to 50%.

[0470] Furthermore, as other hosts other than the above, one or more known hosts can be used in combination, but the usage amount can be set to 50% or less, preferably 25% or less, of the total amount of the host materials.

[0471] As the other known hosts that can be used, compounds having hole transport ability, electron transport ability, and a high glass transition temperature are preferred, and having a T1 larger than that of the luminescent dopant. Specifically, it is preferred that the T1 of the host is 0.010 eV or more higher than the T1 of the luminescent dopant, more preferably 0.030 eV or more higher, and still more preferably 0.10 eV or more higher. Additionally, as the host material, a compound having TADF activity can also be used, and the compound preferably has a ΔEST of 0.20 eV or less.

[0472] As the other hosts, they are well-known from a large number of patent documents, etc., and thus can be selected from these. Specific examples of the host are not particularly limited, and examples include: indole derivatives, carbazole derivatives, indolocarbazole derivatives, triazole derivatives, oxazole derivatives, oxadiazole derivatives, imidazole derivatives, phenylenediamine derivatives, arylamine derivatives, styryl anthracene derivatives, fluorenone derivatives, stilbene derivatives, triphenylene derivatives, carborane derivatives, porphyrin derivatives, phthalocyanine derivatives, metal complexes of 8-hydroxyquinoline derivatives or metal phthalocyanines, various metal complexes represented by metal complexes of benzoxazole or benzothiazole derivatives, poly(N-vinylcarbazole) derivatives, aniline-based copolymers, thiophene oligomers, polythiophene derivatives, polyphenylene derivatives, polyphenylstyrene derivatives, polyfluorene derivatives, and other polymer compounds, etc.

[0473] In the case of using multiple hosts, each host can also be vapor-deposited from different vapor-deposition sources, or pre-mixed before vapor-deposition to form a pre-mixture, and thus multiple hosts can be vapor-deposited simultaneously from one vapor-deposition source.

[0474] As a premixing method, a method that can be mixed as uniformly as possible is desirable. Examples include pulverization mixing, or a method of heating and melting under reduced pressure or in an inert gas environment such as nitrogen, or sublimation, etc., but it is not limited to these methods.

[0475] The form of the premix can be powder, rod-shaped, or granular.

[0476] When the compound of the present invention is used for a host, the energy level of the highest occupied molecular orbital (HOMO) obtained by structural optimization calculation based on density functional calculation B3LYP / 6-31G(D) is preferably -4.7 eV or less, more preferably in the range of -5.5 eV to -4.7 eV.

[0477] In addition, the energy level of the lowest unoccupied molecular orbital (LUMO) obtained by the structural optimization calculation is preferably -2.5 eV or more, more preferably in the range of -2.5 eV to -1.5 eV.

[0478] When the compound of the present invention is used for a host, the difference (absolute value) between the HOMO energy level and the LUMO energy level is preferably in the range of 2.2 eV to 3.5 eV, more preferably in the range of 2.5 eV to 3.3 eV.

[0479] As the luminescent dopant in the light-emitting layer, the polycyclic aromatic compound material represented by the general formula (1), or the general formula (7a) or general formula (7b), specifically the general formula (8a) or general formula (8b) can be used. In addition, a phosphorescent dopant can also be used.

[0480] The phosphorescent dopant material is not particularly limited, and specific examples are as follows.

[0481] [Chemical formula 120]

[0482]

[0483] [Chemical formula 121]

[0484]

[0485] [Chemical formula 122]

[0486]

[0487] [Chemical formula 123]

[0488]

[0489] The light-emitting layer may contain two or more light-emitting dopants. For example, two or more of the compounds represented by the general formula (1), or the polycyclic aromatic compound materials represented by the general formula (7a) or the general formula (7b), specifically, the general formula (8a) or the general formula (8b) may be used in combination, or these polycyclic aromatic compound materials may be combined with a phosphorescent light-emitting dopant, and further, a light-emitting dopant containing other compounds may be combined to contain two or more light-emitting dopants. When the light-emitting layer contains the compound represented by the general formula (1), or the polycyclic aromatic compound material represented by the general formula (7a) or the general formula (7b), specifically, the general formula (8a) or the general formula (8b), it is preferable to contain the compound represented by the general formula (1) as a host material and the polycyclic aromatic compound material represented by the general formula (7a) or the general formula (7b), specifically, the general formula (8a) or the general formula (8b) as a light-emitting dopant.

[0490] When the light-emitting layer contains two or more light-emitting dopants, the first dopant is a compound or a fluorescent light-emitting dopant represented by the general formula (7a), the general formula (7b), the general formula (8a), or the general formula (8b), and a known compound can be used in combination as the second dopant as a light-emitting dopant. As for the content thereof, it is preferably that the first dopant is 0.050% to 50% relative to the host material, and the second dopant is 0.050% to 50% relative to the host material, and the total content of the first dopant and the second dopant does not exceed 50% relative to the host material.

[0491] As such other light-emitting dopants, they are known from a large number of patent documents and the like, and thus can be selected from these. Specific examples of the dopant are not particularly limited, and examples include: phenanthrene, anthracene, pyrene, tetracene, pentacene, perylene, naphthopyrene, dibenzopyrene, rubrene, and Condensed ring derivatives, benzoxazole derivatives, benzothiazole derivatives, benzimidazole derivatives, benzotriazole derivatives, oxazole derivatives, oxadiazole derivatives, thiazole derivatives, imidazole derivatives, thiadiazole derivatives, triazole derivatives, pyrazoline derivatives, stilbene derivatives, thiophene derivatives, tetraphenylbutadiene derivatives, cyclopentadiene derivatives, bisstyrylanthracene derivatives or bisstyrylbenzene derivatives such as bisstyryl derivatives, bisstyrylarylene derivatives, diazabenzodindene derivatives, furan derivatives, benzofuran derivatives, isobenzofuran derivatives, dibenzofuran derivatives, coumarin derivatives, dicyanomethylene pyran derivatives, dicyanomethylene thiopyran derivatives, polymethine derivatives, cyanine derivatives, oxobenzanthracene derivatives, xanthene derivatives, rhodamine derivatives, fluorescein derivatives, pyranylium derivatives, quinolone derivatives, acridine derivatives, oxazine derivatives, phenyl ether derivatives, quinacridone derivatives, quinazoline derivatives, pyrrolopyridine derivatives, fluoropyridine derivatives, 1,2,5-thiadiazolo pyrene derivatives, pyrromethene derivatives, violanthrone derivatives, pyrrolopyrrole derivatives, squarylium derivatives, anthrone violet derivatives, phenazine derivatives, acridone derivatives, deazaflavin derivatives, fluorene derivatives and benzofluorene derivatives, etc.

[0492] The light-emitting dopant and the first host or the second host may also be vapor-deposited from different vapor-deposition sources respectively, or pre-mixed before vapor-deposition to form a pre-mixture, and thus the light-emitting dopant and the first host or the second host are vapor-deposited simultaneously from one vapor-deposition source.

[0493] - Injection layer -

[0494] The so-called injection layer is a layer provided between the electrode and the organic layer to reduce the driving voltage or increase the light-emitting brightness. There are a hole injection layer and an electron injection layer, which may exist 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. The injection layer can be provided as needed.

[0495] - Hole blocking layer -

[0496] Generally speaking, the so-called hole blocking layer has the function of an electron transport layer, and includes a hole blocking material having the function of transporting electrons and significantly small ability to transport holes. It can increase the recombination probability of electrons and holes in the light-emitting layer by transporting electrons and blocking holes. In the hole blocking layer, known hole blocking materials can be used. In order to exert the characteristics of the light-emitting dopant, the material used as the first host can also be used as the material of the hole blocking layer, and the general formula (1) of the compound of the present invention can be used. In addition, multiple hole blocking materials can also be used in combination.

[0497] - Electron blocking layer -

[0498] The so-called electron blocking layer, generally speaking, has the function of a hole transport layer, and can increase the probability of recombination of electrons and holes in the light-emitting layer by transporting holes and blocking electrons. As the material for the electron blocking layer, known electron blocking layer materials can be used. In order to exert the characteristics of the luminescent dopant, the material used as the second host can also be used as the material for the electron blocking layer. The film thickness of the electron blocking layer is preferably 3 nm to 100 nm, more preferably 5 nm to 30 nm.

[0499] -Exciton blocking layer-

[0500] The so-called exciton blocking layer is a layer used to block the diffusion of excitons generated by the recombination of holes and electrons in the light-emitting layer to the charge transport layer. By inserting this layer, excitons can be efficiently encapsulated in the light-emitting layer, and the luminous efficiency of the device can be improved. The exciton blocking layer can be inserted between two adjacent light-emitting layers in a device where two or more light-emitting layers are adjacent.

[0501] As the material for the exciton blocking layer, known exciton blocking layer materials can be used.

[0502] As the layer adjacent to the light-emitting layer, there are a hole blocking layer, an electron blocking layer, an exciton blocking layer, etc. In the case where these layers are not provided, a hole transport layer, an electron transport layer, etc. become the adjacent layers.

[0503] -Hole transport layer-

[0504] The so-called hole transport layer contains a hole transport material having the function of transporting holes, and the hole transport layer can be provided as a single layer or multiple layers.

[0505] As the hole transport material, it is a material having any one of the functions of hole injection or transport and electron barrier properties, and can be either an organic substance or an inorganic substance. In the hole transport layer, any one can be selected from the previously known compounds and used. As the hole transport material, for example, porphyrin derivatives, triazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, oxazole derivatives, styryl anthracene derivatives, fluorenone derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives, aniline-based copolymers, and conductive polymer oligomers, especially thiophene oligomers, etc. are preferably used, and porphyrin derivatives, arylamine derivatives, and styrylamine derivatives are more preferably used.

[0506] -Electron transport layer-

[0507] The so-called electron transport layer contains a material having the function of transporting electrons, and the electron transport layer can be provided as a single layer or multiple layers.

[0508] As an electron transport material (which sometimes also serves as a hole blocking material), it only needs to have the function of conveying the electrons injected from the cathode to the light-emitting layer. The electron transport layer can be selected from any of the previously known compounds and used, for example, polycyclic aromatic derivatives such as naphthalene, anthracene, phenanthroline, tris(8-hydroxyquinoline) aluminum(III) derivatives, phosphine oxide derivatives, nitro-substituted fluorene derivatives, diphenylquinone derivatives, thianthrene dioxide derivatives, carbodiimide, fluoreneylidene methane derivatives, anthraquinone dimethane and anthrone derivatives, bipyridine derivatives, quinoline derivatives, oxadiazole derivatives, benzimidazole derivatives, benzothiazole derivatives, indolocarbazole derivatives, etc. Furthermore, a polymer material in which these materials are introduced into the polymer chain or these materials are used as the main chain of the polymer can also be used.

[0509] The film formation method of each layer when manufacturing the organic EL element of the present invention is not particularly limited, and either a dry process or a wet process can be used for manufacturing.

[0510] Examples

[0511] Calculation Examples

[0512] Calculation of HOMO and LUMO Values

[0513] For the compounds 1-1, 1-10, 1-11, 1-51, 1-52, 1-55, 1-105, 1-106, 1-122, 1-124, 1-126, and 1-127, HOMO and LUMO were calculated. In addition, for the calculation, a calculation based on the density functional method (DFT: Density Functional Theory) was used, and as the calculation program, Gaussian was used, and the calculation was performed through a structural optimization calculation based on density functional calculation B3LYP / 6-31G(d). The results are shown in Table 1 below. It can be said that any material of the present invention has preferable HOMO and LUMO values.

[0514] [Table 1]

[0515] Compound HOMO (eV) LUMO (eV) 1-1 -5.2 -1.9 1-10 -5.3 -2.0 1-11 -5.1 -2.0 1-51 -5.2 -2.0 1-52 -5.1 -2.0 1-55 -5.1 -2.0 1-105 -5.2 -1.9

[0516] Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited to these examples.

[0517] First, as representative examples, synthesis examples of several compounds are shown. For other compounds, they are also synthesized by similar methods.

[0518] Synthesis Example 1 (Synthesis of Compound 1-51)

[0519] [Chemical formula 124]

[0520]

[0521] Charge T1 (56.2 mmol), T2 (37.4 mmol), tetrakis(triphenylphosphine)palladium(0) (7.5 mmol), and potassium carbonate (1.12 mol) into a 2000 ml three-necked flask purged with degassed nitrogen. After adding 900 ml of toluene, 200 ml of ethanol, and 200 ml of water thereto, stir at 100 °C for 4 hours. After temporarily cooling to room temperature, add 500 ml of water, transfer to a separatory funnel, and separate into an organic layer and an aqueous layer. Wash the organic layer three times with 500 ml of water, and then concentrate the obtained organic layer under reduced pressure. Purify the obtained residue by column chromatography to obtain compound T3 (white solid). The yield is 21%.

[0522] [Chemical formula 125]

[0523]

[0524] Charge T3 (27.2 mmol), T4 (59.9 mmol), and tripotassium phosphate (100.9 mmol) into a 300 ml three-necked flask purged with degassed nitrogen. After adding 70 ml of 1,3-dimethyl-2-imidazolidinone (DMI) thereto, stir at 190 °C for 16 hours. After temporarily cooling to room temperature, add 200 ml of water, and filter the precipitated solid. Purify the obtained solid by column chromatography to obtain compound 1-51 (pale yellow solid). The yield is 67%. APCI-TOFMS m / z 970 [M+1] +

[0525] Synthesis Example 2 (Synthesis of Compound 1-68)

[0526] [Chemical formula 126]

[0527]

[0528] Into a 1000 ml three-necked flask purged with degassed nitrogen, charge T1 (28.1 mmol), T5 (16.7 mmol), tetrakis(triphenylphosphine)palladium(0) (3.8 mmol), and potassium carbonate (5.56 mol). After adding 450 ml of toluene, 100 ml of ethanol, and 100 ml of water thereto, stir at 100 °C for 4 hours. After temporarily cooling to room temperature, add 300 ml of water, transfer to a separatory funnel, and separate into an organic layer and an aqueous layer. Wash the organic layer three times with 300 ml of water, and then concentrate the obtained organic layer under reduced pressure. Purify the obtained residue by column chromatography to obtain compound T6 (white solid). The yield is 19%.

[0529] [Chemical Formula 127]

[0530]

[0531] Into a 300 ml three-necked flask purged with degassed nitrogen, charge T6 (10.9 mmol), T7 (24.0 mmol), and tripotassium phosphate (43.5 mmol). After adding 30 ml of 1,3-dimethyl-2-imidazolidinone (DMI) thereto, stir at 190 °C for 16 hours. After temporarily cooling to room temperature, add 100 ml of water, and filter the precipitated solid. Purify the obtained solid by column chromatography to obtain compound 1-68 (pale yellow solid). The yield is 71%. APCI-TOFMS m / z 1046 [M+1] +

[0532] Synthesis Example 3 (Synthesis of Compound 1-106)

[0533] [Chemical Formula 128]

[0534]

[0535] Into a 300 ml three-necked flask purged with degassed nitrogen, charge T3 (9.9 mmol), T8 (9.9 mmol), and tripotassium phosphate (43.5 mmol). After adding 30 ml of DMI thereto, stir at 170 °C for 16 hours. After temporarily cooling to room temperature, add 100 ml of water, and filter the precipitated solid. Purify the obtained solid by column chromatography to obtain compound 1-68 (pale yellow solid). The yield is 54%.

[0536] [Chemical Formula 129]

[0537]

[0538] Charge T3 (3.0 mmol), T8 (3.1 mmol), and tripotassium phosphate (20.5 mmol) into a 300 mL three-necked flask purged with degassed nitrogen. After adding 10 mL of 1,3-dimethyl-2-imidazolidinone (DMI) thereto, stir at 190 °C for 16 hours. After temporarily cooling to room temperature, add 50 mL of water and filter the precipitated solid. Purify the obtained solid by column chromatography to obtain Compound 1-106 (pale yellow solid). The yield is 70%. APCI-TOFMS m / z 970 [M+1] +

[0539] Synthesis Example 4 (Synthesis of Compound 1-127)

[0540] [Chemical Formula 130]

[0541]

[0542] Add 150 mL of deuterated benzene (C6D6) and 9.0 g of deuterated trifluoromethanesulfonic acid (Trifluoromethanesulfonic acid, TfOD) to 1-51 (10.1 mmol) in a 300 mL three-necked flask purged with degassed nitrogen. Heat and stir at 50 °C for 6.5 hours under a nitrogen atmosphere. Add the reaction solution to a deuterated aqueous solution (200 mL) of sodium carbonate (7.0 g) and rapidly cool to obtain a solid. Purify the obtained solid by column chromatography to obtain Compound 1-127 (pale yellow solid) (average deuteration rate: 78%). The yield is 44%. APCI-TOFMS m / z 1013 [M+1] +

[0543] Here, the average deuteration rate can be determined by mass analysis or proton nuclear magnetic resonance spectroscopy. For example, in the case of determining by proton nuclear magnetic resonance spectroscopy, first, a measurement sample is prepared by adding a compound and an internal standard substance to a deuterated solvent and dissolving them. According to the integral intensity ratio of the internal standard substance to the compound source, the proton concentration [mol / g] of the compound contained in the measurement sample is calculated. Next, the ratio of the proton concentration of the deuterated compound to the proton concentration of the corresponding non-deuterated compound is calculated and subtracted from 1, whereby the average deuteration rate of the deuterated compound can be calculated. Regarding Compound 1-127, the method for determining the average deuteration rate by proton nuclear magnetic resonance spectroscopy is shown below. First, a measurement sample is prepared by dissolving Compound 1-127 (5.0 mg) and dimethyl sulfone (2.0 mg) as an internal standard substance in deuterated tetrahydrofuran (1.0 ml). According to the integral intensity ratio of the internal standard substance to Compound 1-127 source, the average proton concentration [mol / g] of Compound 1-127 contained in the measurement sample is calculated. In addition, the average proton concentration [mol / g] is similarly calculated for the non-deuterated form of Compound 1-127 (corresponding to Compound 1-51). Next, the ratio of the proton concentration of Compound 1-127 to the proton concentration of the non-deuterated form of Compound 1-127 is calculated and subtracted from 1, whereby the average deuteration rate of Compound 1-127 is calculated.

[0544] In addition, Compound 1-127 shows an example of the structural formula when all the hydrogens of the compound represented by Formula (1) are deuterated.

[0545] The compounds used in the examples and comparative examples are shown below.

[0546] [Chemical Formula 131]

[0547]

[0548] [Chemical Formula 132]

[0549]

[0550] [Chemical Formula 133]

[0551]

[0552] Measure S1 and T1 of Compound 2-2, Compound 4-2, and Compound 4-13.

[0553] S1 and T1 are measured in the following manner.

[0554] On a quartz substrate, using a vacuum evaporation method, at a vacuum degree of 10 -4Under the condition of Pa or less, the compound (7-58) as the main body and the compound 2-2, compound 4-2 or compound 4-13 as the luminescent dopant are co-evaporated from different evaporation sources respectively to form an evaporation film with a thickness of 100 nm. At this time, co-evaporation is carried out under the evaporation condition that the concentration of the luminescent dopant becomes 3%.

[0555] Regarding S1, the luminescence spectrum of the evaporation film is measured, a tangent line is drawn from the rising of the short wavelength side of the luminescence spectrum, and the wavelength value λedge [nm] of the intersection point of the tangent line and the horizontal axis is substituted into the following formula (i) to calculate S1.

[0556] S1 [eV] = 1239.85 / λedge (i)

[0557] Regarding T1, the phosphorescence spectrum of the evaporation film is measured, a tangent line is drawn from the rising of the short wavelength side of the phosphorescence spectrum, and the wavelength value λedge [nm] of the intersection point of the tangent line and the horizontal axis is substituted into formula (ii) to calculate T1.

[0558] T1 [eV] = 1239.85 / λedge (ii)

[0559] The measurement results are shown in Table 2.

[0560] [Table 2]

[0561] Compound S1 (eV) T1 (eV) S1 - T1 (eV) 2-2 2.79 2.61 0.18 4-2 2.71 2.67 0.04 4-13 2.76 2.71 0.05

[0562] Example 1

[0563] On a glass substrate on which an anode containing ITO with a film thickness of 70 nm is formed, each thin film is laminated by vacuum evaporation at a vacuum degree of 4.0×10 -5 Pa. First, HAT-CN is formed on the ITO with a thickness of 10 nm as a hole injection layer, and then HT-1 is formed with a thickness of 25 nm as a hole transport layer. Next, compound 7-58 is formed with a thickness of 5 nm as an electron blocking layer. Next, the compound 1-1 as the first host, the compound 5-148 as the second host, and the compound 4-2 as the luminescent dopant are co-evaporated from different evaporation sources respectively, and the light-emitting layer is formed with a thickness of 30 nm. At this time, co-evaporation is carried out under the evaporation condition that the concentration of compound 4-2 becomes 2% and the mixing ratio of the first host and the second host is 30:70. Next, compound H6 is formed with a thickness of 5 nm as a hole blocking layer. Next, ET-1 is formed with a thickness of 40 nm as an electron transport layer. Lithium fluoride (LiF) is formed with a thickness of 1 nm as an electron injection layer on the electron transport layer. Finally, aluminum (Al) is formed with a thickness of 70 nm as a cathode on the electron injection layer to fabricate an organic EL element.

[0564] Examples 2 to 6, 8 to 10, 12 to 22, Comparative Examples 1 to 11

[0565] An organic EL element was fabricated in the same manner as in Example 1, except that the luminescent dopant, the first host, the second host, the hole blocking layer, and the mixing ratio of the first host to the second host were set to the compounds shown in Table 3. In addition, the mixing ratio is the first host: the second host.

[0566] Examples 7 and 11

[0567] An organic EL element was fabricated in the same manner as in Example 6, except that the luminescent dopant, the first host, the second host, the hole element layer, and the mixing ratio of the first host to the second host were set to the compounds shown in Table 3. In addition, the mixing ratio is the first host: the second host.

[0568] [Table 3]

[0569] Luminescent dopant First host Second host Mixing ratio Hole blocking layer Example 1 4-2 1-1 5-148 30：70 H6 Example 2 4-2 1-10 5-148 30：70 H6 Example 3 4-2 1-11 5-148 30：70 H6 Example 4 4-2 1-51 5-148 30：70 H6 Example 5 4-2 1-51 6-2 50：50 H6 Example 6 4-2 1-51 6-4 50：50 H6 Example 7 4-2 1-51 6-4 50：50 1-51 Example 8 4-13 1-51 7-58 50：50 H6 Example 9 4-2 1-52 5-148 30：70 H6 Example 10 4-2 1-55 5-148 30：70 H6 Example 11 4-2 1-55 5-148 30：70 1-51 Example 12 4-2 1-65 5-148 30：70 H6 Example 13 4-2 1-68 5-115 30：70 H6 Example 14 4-2 1-105 5-179 30：70 H6 Example 15 4-2 1-106 5-148 30：70 H6 Example 16 4-2 1-122 5-148 30：70 H6 Example 17 4-2 1-124 5-148 30：70 H6 Example 18 4-2 1-126 5-148 30：70 H6 Example 19 4-2 1-127 5-148 30：70 H6 Example 20 2-2 1-6 7-58 30：70 H6 Example 21 2-2 1-6 7-31 30：70 H6 Example 22 2-2 1-6 7-81 30：70 H6 Comparative Example 1 4-2 H1 5-148 30：70 H6 Comparative Example 2 4-2 H2 5-148 30：70 H6 Comparative Example 3 4-2 H3 5-148 30：70 H6 Comparative Example 4 4-2 H4 5-148 30：70 H6 Comparative Example 5 4-2 H5 5-148 30：70 H6 Comparative Example 6 4-2 H6 5-148 30：70 H6 Comparative Example 7 4-2 H6 6-2 50：50 H6 Comparative Example 8 4-2 H6 6-4 50：50 H6 Comparative Example 9 4-13 H6 7-58 30：70 H6 Comparative Example 10 4-13 H6 mCBP 30：70 H6 Comparative Example 11 2-2 H6 7-58 30：70 H6 Comparative Example 12 4-2 H7 5-148 30：70 H6

[0570] The maximum emission wavelength, external quantum efficiency, and element lifetime of the organic EL elements fabricated in the examples and comparative examples are shown in Table 4. The maximum emission wavelength and external quantum efficiency are values at a current density of 2.5 mA / cm 2 and are initial characteristics. Regarding the element lifetime, the time until the luminance decays to 70% of the initial luminance was measured when the current density was 2.5 mA / cm 2 .

[0571] [Table 4]

[0572]

[0573] As can be seen from Table 4, the organic EL elements of Examples 1 to 6, 8 to 10, 12 to 22, and Comparative Examples 1 to 12 have the characteristics of high efficiency and long lifetime, and emit blue light according to the maximum emission wavelength, and thus show excellent characteristics compared to known compounds as host materials. It can be seen that when comparing Example 6 with Example 7 and Example 10 with Example 11, the elements using the compound represented by the general formula (1) in the hole blocking layer also show the characteristic of long lifetime compared to known compounds.

[0574] Example 23

[0575] On a glass substrate on which an anode including ITO with a film thickness of 70 nm was formed, by vacuum evaporation at a degree of vacuum of 4.0×10 -5Stack the thin films. First, form HAT-CN on ITO to a thickness of 10 nm as a hole injection layer. Next, form HT-1 to a thickness of 25 nm as a hole transport layer. Next, form Compound 7-58 to a thickness of 5 nm as an electron blocking layer. Next, co-evaporate Compound 7-58 as a host and Compound 1-51 as a luminescent dopant from separate evaporation sources to form a light-emitting layer to a thickness of 30 nm. At this time, co-evaporation is performed under evaporation conditions where the concentration of Compound 1-51 becomes 30%. Next, form Compound H6 to a thickness of 5 nm as a hole blocking layer. Next, form ET-1 to a thickness of 40 nm as an electron transport layer. Further, form lithium fluoride (LiF) to a thickness of 1 nm as an electron injection layer on the electron transport layer. Finally, form aluminum (Al) to a thickness of 70 nm as a cathode on the electron injection layer, thereby fabricating an organic EL element.

[0576] Comparative Examples 13 and 14

[0577] An organic EL element was fabricated in the same manner as in Example 23, except that the luminescent dopant was the compound shown in Table 5.

[0578] The maximum emission wavelength, external quantum efficiency, and lifetime of the organic EL elements fabricated in the examples and comparative examples are shown in Table 5. The maximum emission wavelength and external quantum efficiency are values when the current density is 2.5 mA / cm 2 and are initial characteristics. Regarding the lifetime, the time until the luminance decays to 70% of the initial luminance when the current density is 2.5 mA / cm 2 was measured.

[0579] [Table 5]

[0580]

[0581] From Table 5, it can be seen that the organic EL elements of the examples have the characteristics of high efficiency and long lifetime, and emit blue light according to the maximum emission wavelength.

[0582] The compounds used in the examples and comparative examples are shown below.

[0583] [Chemical Formula 134]

[0584]

[0585] [Chemical Formula 135]

[0586]

[0587] Example 24

[0588] On a glass substrate on which an anode containing ITO with a film thickness of 70 nm is formed, each thin film is laminated by a vacuum evaporation method at a degree of vacuum of 4.0×10 -5 Pa. First, HAT-CN is formed on the ITO to a thickness of 25 nm as a hole injection layer, and then Spiro-TPD is formed to a thickness of 30 nm as a hole transport layer. Next, HT-2 is formed to a thickness of 10 nm as an electron blocking layer. Next, a compound 1-1 as a host and Ir(ppy)3 as a light-emitting dopant are co-evaporated from different evaporation sources respectively, and the light-emitting layer is formed to a thickness of 40 nm. At this time, co-evaporation is performed under evaporation conditions in which the concentration of Ir(ppy)3 becomes 10 wt%. Next, ET-1 is formed to a thickness of 20 nm as an electron transport layer. Further, LiF is formed to a thickness of 1 nm on the electron transport layer as an electron injection layer. Finally, Al is formed to a thickness of 70 nm on the electron injection layer as a cathode, thereby fabricating an organic EL element.

[0589] Examples 25 to 39, Comparative Examples 15 to 20

[0590] An organic EL element was fabricated in the same manner as in Example 24 except that the compound shown in Table 6 was used as the host.

[0591] The evaluation results of the fabricated organic EL elements are shown in Table 6. In the table, the luminance, voltage, and power efficiency are values at a driving current of 10 mA / cm 2 and are initial characteristics. LT97 is the time elapsed until the luminance decays to 97% when the initial luminance at a driving current of 20 mA / cm 2 is set to 100%, and represents the element lifetime. The numbers of the host compounds are the numbers attached to the exemplified compounds.

[0592] [Table 6]

[0593]

[0594] Example 40

[0595] On a glass substrate on which an anode containing ITO with a film thickness of 110 nm is formed, by a vacuum evaporation method at a degree of vacuum of 4.0×10 -5The following describes the process of laminating each thin film. First, HAT-CN is formed on ITO to a thickness of 25 nm as a hole injection layer. Next, Spiro-TPD is formed to a thickness of 30 nm as a hole transport layer. Then, HT-2 is formed to a thickness of 10 nm as an electron blocking layer. Next, compound 1-1 as the first host, compound 6-2 as the second host, and Ir(ppy)3 as a light-emitting dopant are co-evaporated from different evaporation sources respectively, and the light-emitting layer is formed to a thickness of 40 nm. At this time, co-evaporation is performed under the evaporation conditions where the concentration of Ir(ppy)3 is 10 wt% and the weight ratio of the first host to the second host is 30:70. Next, ET-1 is formed to a thickness of 20 nm as an electron transport layer. Further, LiF is formed to a thickness of 1 nm on the electron transport layer as an electron injection layer. Finally, Al is formed to a thickness of 70 nm on the electron injection layer as a cathode, thereby fabricating an organic EL element.

[0596] Examples 41 to 57, Comparative Examples 21 to 26

[0597] An organic EL element is fabricated in the same manner as in Example 40, except that the first host, the second host, and the mixing ratio of the first host to the second host are set to the compounds shown in Table 7.

[0598] The evaluation results of the fabricated organic EL elements are shown in Table 7. In the table, the luminance, voltage, and power efficiency are the values at a driving current of 10 mA / cm 2 and represent the initial characteristics. LT97 is the time elapsed until the luminance decays to 97% when the initial luminance at a driving current of 20 mA / cm 2 is set to 100%, and represents the element lifetime. The mixing ratio is the first host: the second host.

[0599] [Table 7]

[0600]

[0601] From the results of Tables 6 and 7, it can be seen that the lifetimes in Examples 40 to 57 are improved compared to the comparative examples, showing good characteristics.

[0602] Explanation of reference numerals

[0603] 1: Substrate

[0604] 2: Anode

[0605] 3: Hole injection layer

[0606] 4: Hole transport layer

[0607] 5: Light-emitting layer

[0608] 6: Electron transport layer

[0609] 7: Cathode

Claims

1. A compound represented by the following general formula (1). [Chemical formula 1] Here, Ar 1 represents the following general formula (2). [Chemical formula 2] R 1 Each independently represents deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, or a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms. R 11 Each independently represents hydrogen, deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, or a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms. a 0 Represents the number of substitutions, an integer from 0 to 3; s and c represent the number of substitutions, s independently represents an integer from 0 to 3, c independently represents an integer from 0 to 4; n and m represent the number of repetitions, each independently represents an integer from 1 to 3, and at least one of n or m represents 2 or 3. * represents the bond node of the general formula (1). X 1 independently represents N, or C-R 2 , at least one X 1 represents N. R 2 independently represents hydrogen, deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to eight of the aromatic hydrocarbon groups. Ar 2 and Ar 3 represents hydrogen, a C1-C10 aliphatic hydrocarbon group, a substituted or unsubstituted C6-C18 aromatic hydrocarbon group, a substituted or unsubstituted C3-C17 aromatic heterocyclic group, or a substituted or unsubstituted linked aromatic group formed by linking two to eight of these aromatic groups. Ar 0 represents deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to eight of these aromatic groups.

2. The compound according to claim 1, wherein the general formula (1) is represented by the following general formula (3). [Chemical formula 3] Here, Ar 1 ~Ar 3 has the same meaning as in the case of the general formula (1).

3. The compound according to claim 1, wherein Ar 1 contains at least one linking carbazolyl group represented by any one of the following general formulas (4a) to (4c). [Chemical formula 4] Here, R 1 and c have the same meanings as in the case of the general formula (2). a and b represent the number of substituents, a independently represents an integer of 0 to 4, b independently represents an integer of 0 to 3; ※ represents the bonding point of the benzene ring of the general formula (2).

4. The compound according to claim 1, wherein Ar 1 is represented by any one of the following general formulas (5a) to (5e). [Chemical formula 5] [Chemical formula 6] Here, R 1 , c, and * have the same meanings as in the case of the general formula (2). a and b have the same meanings as in the cases of the general formulas (4a) to (4c).

5. The compound according to claim 1, wherein Ar 2 and Ar 3 is represented by hydrogen, deuterium, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to eight of said aromatic hydrocarbon groups.

6. The compound according to claim 1, wherein the general formula (1) is represented by any one of the following general formulas (6a) to (6c). [Chemical formula 7] Here, R 1 , and c have the same meanings as in the general formula (2), and are each independent. In addition, a and b have the same meanings as in the general formulas (4a) to (4c). f independently represents the number of substitutions and represents an integer of 0 to 5.

7. The compound according to claim 1, wherein at least one of Ar 1 ~Ar 3 contains a deuterium atom.

8. The compound according to claim 1, wherein at least one of Ar 2 and Ar 3 contains a deuterium atom.

9. The compound according to claim 1, wherein at least one R 1 is deuterium.

10. A material for an organic electroluminescent element, which contains the compound represented by the general formula (1).

11. An organic electroluminescent element, which includes one or more light-emitting layers between an opposing anode and cathode, and is characterized in that at least one light-emitting layer contains a host selected from the compounds represented by the general formula (1) and a light-emitting dopant.

12. The organic electroluminescent device according to claim 11, wherein Contains: a host selected from the compounds represented by the general formula (1) and a light-emitting dopant selected from polycyclic aromatic compounds represented by the following general formula (7a) or general formula (7b). [Chemical formula 8] Here, ring J, ring K, ring C, ring D, ring E, ring F, ring G, and ring H are each independently a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 24 carbon atoms or a substituted or unsubstituted aromatic heterocyclic ring having 3 to 17 carbon atoms. Y 1 are each independently B, P, P═O, P═S, Al, Ga, As, Si-R 3 or Ge-R 3 , R 3 each independently is an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms X 2 are each independently O, N-Ar 4 , S or Se, Ar 4 is each independently a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to eight of these, N-Ar 4 may be bonded to any one of ring J, ring K, ring C, ring D, ring E, ring F, ring G, or ring H to form a heterocycle containing N. R 4 each independently represents cyano, deuterium, a diarylamino group having 12 to 44 carbon atoms, an arylheteroarylamino group having 12 to 44 carbon atoms, a diheteroarylamino group having 12 to 44 carbon atoms, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms. g and h represent the number of substituents, each independently representing an integer of 0 to 4, i and j represent the number of substituents, each independently representing an integer of 0 to 3, and k represents the number of substituents, representing an integer of 0 to 2.

13. The organic electroluminescent device according to claim 11, wherein, Contains: a host selected from the compounds represented by the general formula (1) and a light-emitting dopant selected from polycyclic aromatic compounds represented by the following general formula (8a) or general formula (8b). [Chemical formula 9] Here, X 3 independently represents N-Ar 4 , O, or S, provided that at least one X 3 represents N-Ar 4 . Ar 4 , R 4 , g, h, i, j, and k have the same meanings as in the case of the general formula (7a) or general formula (7b).

14. The organic electroluminescent device according to claim 11, wherein The difference (ΔEST) between the singlet excitation energy (S1) and the triplet excitation energy (T1) in the light-emitting dopant is 0.20 eV or less.

15. The organic electroluminescent element according to claim 14, wherein The ΔEST is 0.10 eV or less.

16. The organic electroluminescent device according to claim 11, wherein The light-emitting dopant is a phosphorescent light-emitting dopant.

17. The organic electroluminescent element according to any one of claims 11 to 16, characterized in that, Contains a first host, a light-emitting dopant, and a second host selected from the compounds represented by the general formula (1).

18. The organic electroluminescent device according to claim 17, wherein, The second host is selected from the compounds represented by the following general formula (9), or is selected from the compounds represented by general formula (9a) or general formula (9b). [Chemical formula 10] In general formula (9), Z is a group containing an indolocarbazole ring represented by general formula (10), ** represents the bond node with L 1 In addition, ring A in general formula (10) is a heterocyclic ring represented by general formula (11), and ring A is condensed with the adjacent ring at an arbitrary position. wherein, L 1 and L 2 are each independently a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms or a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, Ar 5 and Ar 6 are each independently deuterium, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to eight of these aromatic groups. R 5 Independently deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms. v represents the number of substituents, which is an integer from 1 to 3, w represents the number of substituents, which is an integer from 0 to 3, q 1 and q 3 represents the number of substituents, which are independently integers from 0 to 4, q 2 represents the number of substituents, which is an integer from 0 to 2, r represents the number of substituents, which is an integer from 0 to 3. [Chemical formula 11] Z, Ar 5 , v and w have the same meanings as in general formula (9), and X 4 represents O or S. R 6 are each independently deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms.

19. The organic electroluminescent element according to claim 17, characterized in that, The second host is selected from the compounds represented by the following general formula (12) or general formula (13). [Chemical formula 12] Here, Ar 7 , and Ar 8 each independently represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to eight of these aromatic groups. R each independently represents deuterium or an aliphatic hydrocarbon group having 1 to 10 carbon atoms. e 1 ~e 4 respectively represent the substitution numbers, e 1 and e 4 independently represent integers from 0 to 4, e 2 and e 3 independently represent integers from 0 to 3. [Chemical formula 13] Here, Ar 9 represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to eight of these aromatic groups. R 7 each independently represents deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms. R 77 independently represents hydrogen, deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, or a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms. t 1 ~t 4 respectively represent the substitution number, t 3 and t 4 independently represent an integer from 0 to 4, t 1 and t 2 independently represent an integer from 0 to 3. p represents the repetition number, independently represents an integer from 1 to 4, u represents the substitution number, represents an integer of 1 or 2; when u is 2, the general formula (13) can be symmetric or asymmetric.

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