Compound, material for organic electroluminescent element, and 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. A1 represents hydrogen, deuterium, an aromatic hydrocarbon group having 6-18 carbon atoms, or the like; and Ar2 to Ar4 are represented by formula (2) or the like. R1 and R11 are deuterium, an aliphatic hydrocarbon group having 1-10 carbon atoms, and an aromatic hydrocarbon group having 6-18 carbon atoms, a represents an integer of 0-4, and b represents an integer of 0-7. D represents an integer of 1-3, but at least one represents 2 or 3; * represents a bond point to general formula (1). Wherein at least one of Ar2 and Ar3 contains a linked carbazolyl group represented by formulae (3a) to (3c). And c represents an integer of 0-8. # imgabs0 #

Description

Technical Field

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

[0002] By applying a voltage to an organic electroluminescence (EL) element, holes are injected from the anode into the light-emitting layer, and electrons are injected from the 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 element 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 element 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 elements, further extending the lifetime has become a technical issue.

[0004] Furthermore, recently, highly efficient organic EL elements using delayed fluorescence have been developed. For example, Patent Document 1 discloses an organic EL element that utilizes the triplet-triplet fusion (TTF) mechanism, which is one of the mechanisms of delayed fluorescence. The TTF mechanism utilizes the phenomenon in which 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 elements, the efficiency is low, and thus further improvement in efficiency is required.

[0005] On the other hand, Patent Document 2 discloses an organic EL element that utilizes the thermally activated delayed fluorescence (TADF) mechanism. The TADF mechanism is a mechanism that utilizes the following phenomenon: in a material in which 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 elements, further improvement in lifetime characteristics is required, and in particular, improvement in lifetime characteristics is required for blue-emitting organic EL elements.

[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] In Patent Document 4, there is disclosed 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 a 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 a 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 linking a nitrogen-containing 6-membered ring represented by the following compound with a bis-carbazole or a tricarbazole 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 linking a nitrogen-containing 6-membered ring represented by the following compound with a carbazole as a host material.

[0044] [Chemical formula 7]

[0045]

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

[0047] [Chemical Formula 8]

[0048]

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

[0050] [Chemical Formula 9]

[0051]

[0052] In Patent Document 14, there is disclosed a phosphorescent organic EL element 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, there is disclosed an organic EL element 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, there is disclosed an organic EL element which is used by mixing a boron compound, a compound H1 or a compound H2 formed by linking the following nitrogen-containing 6-membered ring and carbazole in a light-emitting layer.

[0059] [Chemical Formula 12]

[0060]

[0061] In Patent Document 17, there is disclosed an organic EL element which uses a compound H9 formed by linking the following nitrogen-containing 6-membered ring and carbazole.

[0062] [Chemical Formula 13]

[0063]

[0064] However, in any of the documents, there is still room for improvement in the 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 light emission efficiency of the element and at the same time sufficiently ensure the stability during driving. In view of these circumstances, 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 Problems

[0068] The present invention is 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, A 1 represents hydrogen, 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 four of these aromatic groups. Ar 2 and Ar 3 each independently represent the following general formula (2), Ar 4 independently represents the following general formula (2) or deuterium. In addition, A 1 may contain the following general formula (2), and may also contain the general formulas (3a) to (3c) described later.

[0072] [Chemical Formula 15]

[0073]

[0074] R 1 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. R 11 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. a and b represent the number of substitutions, a represents an integer of 0 to 4, and b independently represents an integer of 0 to 7. d represents the number of repetitions and independently represents an integer of 1 to 3, but at least one d represents 2 or 3. * represents the bonding point with the general formula (1). Among them, Ar 2 and Ar 3 at least one of them contains a linked carbazole group represented by the general formulas (3a) to (3c).

[0075] [Chemical Formula 16]

[0076]

[0077] Here, R 1 , b, and * have the same meanings as in the general formula (2). c represents the number of substitutions and independently represents an integer from 0 to 8.

[0078] As a preferred form of the general formula (1), any one of the following general formulas (6a) to (6c) can be cited.

[0079] [Chemical formula 17]

[0080]

[0081] Here, Ar 4 , R 1 , R 11 , a, and b have the same meanings as in the general formulas (1) and (2). R 12 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. d 1 to d 3 represent the number of repetitions and independently represent an integer from 1 to 3. k represents the number of substituents and represents an integer from 0 to 5. Among them, d 2 and d 3 at least one of them represents an integer of 2 or 3, and contains at least one linking carbazole group represented by any one of the formulas (3a) to (3c).

[0082] As a preferred form of the general formulas (6a) to (6c), it can be cited that in the compound represented by the general formula (6a), any one of the following conditions (v) to (vii) is satisfied, and in the compounds represented by the general formulas (6b) and (6c), any one of the following conditions (i) to (iv) is satisfied.

[0083] (i) d 1 = 1, and d 2 = 2 or 3, and d 3 = 1

[0084] (ii) d 1 = 1, and d 2 = 1, and d 3 = 2 or 3

[0085] (iii) d 1 = 2, and d 2 = 2, and d 3 = 1

[0086] (iv) d 1 = 1, and d 2= 2, and d 3 = 2

[0087] (v) d 2 = 1, and d 3 = 2 or 3

[0088] (vi) d 2 = 2 or 3, and d 3 = 1

[0089] (vii) d 2 = 2, and d 3 = 2

[0090] As a preferred form of the general formula (1), Ar 4 is deuterium.

[0091] As a preferred form of the general formula (1), it may be mentioned that it contains at least one deuterium.

[0092] As a preferred form of the general formula (1), A 1 , Ar 2 , Ar 3 and Ar 4 in which at least one is a group having deuterium. More preferably, it may be mentioned that A 1 and Ar 2 in which at least one is a group having deuterium.

[0093] As a preferred form of the general formula (1), Ar 3 is a group having at least one deuterium.

[0094] The compound represented by the general formula (1) is preferably used as a material for an organic electroluminescent element.

[0095] In an organic electroluminescent element including one or more light-emitting layers between an opposing anode and cathode, 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, and the light-emitting dopant is preferably a polycyclic aromatic compound or a phosphorescent light-emitting dopant represented by the following general formula (7a) or general formula (7b).

[0096] [Chemical formula 18]

[0097]

[0098] 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.

[0099] Y 1B, P, P=O, P=S, Al, Ga, As, Si-R, or Ge-R, respectively, independently 2 or Ge-R 2 ,

[0100] R 2 is, respectively, 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

[0101] X 1 is, respectively, independently, O, N-Ar 5 , S, or Se

[0102] Ar 5 is, respectively, 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, and N-Ar 5 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

[0103] R 3 respectively, 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

[0104] p to t represent the number of substituents, p and q respectively, independently, represent an integer of 0 to 4, r and s respectively, independently, represent an integer of 0 to 3, and t represents an integer of 0 to 2

[0105] 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. Further, 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

[0106] [Chemical formula 19]

[0107]

[0108] Here, X 2 respectively, independently, represents N-Ar 5 , O, or S, provided that at least one X 2 represents N-Ar 5 . Ar 5 has the same meaning as in the case of the general formula (7a) and the general formula (7b). R3 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.

[0109] p to t represent the number of substituents, p and q each independently represent an integer of 0 to 4, r and s each independently represent an integer of 0 to 3, and t represents an integer of 0 to 2.

[0110] 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.

[0111] 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). Among them, it is more preferable to contain a compound represented by the following general formula (9), general formula (12), or general formula (13) as the second host.

[0112] First, regarding the general formula (9), it is as follows.

[0113] [Chemical formula 20]

[0114]

[0115] Here, Z is a group containing an indolocarbazole ring represented by the formula (10), * is a bonding point, specifically, it represents the bonding point with L 1 . In addition, ring A is a heterocyclic ring represented by the formula (11), and ring A is condensed with the adjacent ring at an arbitrary position.

[0116] L 1 and L 2 Each independently is 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.

[0117] Ar 6 and Ar 7 Each independently is 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.

[0118] R 5 Each 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.

[0119] v 1 ~v 2 、u 1 ~u 3 、and w represent the number of substitutions, where v 1 represents an integer from 1 to 3, v 2 represents an integer from 0 to 3, u 1 and u 3 each independently represent an integer from 0 to 4, u 2 represents an integer from 0 to 2, and w represents an integer from 0 to 3.

[0120] Here, the general formula (9) can also be represented by the following general formula (9a) or general formula (9b).

[0121] [Chemical formula 21]

[0122]

[0123] Z, Ar 6 、v1 and v2 have the same meanings as in the general formula (9), 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.

[0124] In addition, regarding the general formulas (12) and (13), it is as follows.

[0125] [Chemical formula 22]

[0126]

[0127] Among them, Ar 8 、and Ar 9 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.

[0128] R each independently represents deuterium, or an aliphatic hydrocarbon group having 1 to 10 carbon atoms.

[0129] e 1 ~e 4 represent the number of substitutions, e 1 and e 4 represent integers from 0 to 4, e 2 and e 3 represent integers from 0 to 3.

[0130] [Chemical formula 23]

[0131]

[0132] Here, Ar 10 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.

[0133] 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.

[0134] R 77 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.

[0135] f 1 ~f 4 represents the number of substituents, f 3 and f 4 independently represent integers from 0 to 4, f 1 and f 2 independently represent integers from 0 to 3. In addition, g represents the number of repetitions and independently represents an integer from 1 to 4. Further, h represents the number of substituents and represents an integer of 1 or 2. When h is 2, the general formula (13) can be symmetric or asymmetric.

[0136] In addition, the first host and the second host in the present invention have mutually different structures.

[0137] Effects of the Invention

[0138] The organic EL element using the compound of the present invention can be an organic EL element having high luminous efficiency and long life.

[0139] 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 possessed by the compound represented by the general formula (1) has the property of easily injecting holes, and the nitrogen-containing 6-membered ring possessed by the compound represented by the general formula (1) has the property of easily injecting electrons. Therefore, the balance between 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. Furthermore, it is speculated that the factor for the organic EL element of the present invention to have a long lifespan is that when a voltage is applied to the organic EL element, by preferentially injecting holes into the dicarbazole ring possessed by 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 6-membered ring compound possessed by the compound of the present invention 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.

[0140] 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 its tolerance to holes and electrons is low, it is difficult to ensure the element lifespan 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 lifespan. BRIEF DESCRIPTION OF THE DRAWINGS

[0141] Figure 1 is a schematic cross-sectional view showing an example of an organic EL element. DETAILED DESCRIPTION OF THE INVENTION

[0142] 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).

[0143] ​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 cases are included: a second host selected from the compounds represented by the general formula (9), the compounds represented by the general formula (12), or the compounds represented by the general formula (13), and in addition, a polycyclic aromatic compound represented by the general formula (7a) or the general formula (7b), specifically, a polycyclic aromatic compound represented by the general formula (8a) or the general formula (8b) is contained as the light-emitting dopant, or a phosphorescent light-emitting dopant is contained as the light-emitting dopant.

[0144] The compound represented by the general formula (1) will be described.

[0145] In the general formula (1), A 1 represents hydrogen, 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 four of these aromatic groups.

[0146] In the general formula (1), the formula (2) or any one of the formulas (3a) to (3c) is included. Preferably, A 1 represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 12 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 these aromatic rings, and includes the formula (2) or any one of the formulas (3a) to (3c).

[0147] As A 1 Specific examples when it is an unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms include groups derived from benzene, naphthalene, acenaphthene, acenaphthylene, anthracene, pyrene, phenanthrene, triphenylene, fluorene, or benzo[a]anthracene, etc. 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.

[0148] As A 1Specific examples when it is an unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms 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, indolocarbazole, 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.

[0149] As A 1 Specific examples when it is an unsubstituted linking aromatic group include groups formed by linking two to four 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.

[0150] Ar 2 and Ar 3 each independently represents the formula (2), Ar 4 independently represents the formula (2), or deuterium.

[0151] In the formula (2), R 1 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. Preferred are 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 preferred are deuterium, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 10 carbon atoms.

[0152] 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. Specific examples thereof include straight-chain saturated hydrocarbon groups such as methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-octyl, n-dodecyl, n-tetradecyl, n-octadecyl, branched saturated hydrocarbon groups such as isopropyl, isobutyl, tert-butyl, neopentyl, 2-ethylhexyl, 2-hexyloctyl, etc., and saturated alicyclic hydrocarbon groups such as cyclopentyl, cyclohexyl, cyclooctyl, 4-butylcyclohexyl, 4-dodecylcyclohexyl, etc. Preferred are methyl, ethyl, n-propyl, n-butyl, tert-butyl, neopentyl, or cyclohexyl.

[0153] As R 1 Specific examples when it is an unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms are the same as those described in the above for A 1 .

[0154] Preferred examples include those derived from benzene, naphthalene, anthracene, A group generated from pyrene, phenanthrene, triphenylene, or fluorene. More preferably, examples include groups generated from benzene and naphthalene.

[0155] 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. 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, or a substituted or unsubstituted aromatic hydrocarbon group having 6 to 10 carbon atoms.

[0156] As R 11 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 description in A 1 and R 1 in the above.

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

[0158] a and b represent the number of substitutions. a represents an integer of 0 to 4, and b independently represents an integer of 0 to 7. a is preferably an integer of 0 to 2, and b is preferably an integer of 0 to 5. Among them, when Ar 4 is deuterium, a is preferably an integer of 2 to 4. When R 1 is deuterium, b is preferably an integer of 4 to 7, and R 11 is preferably deuterium.

[0159] d represents the repetition number and independently represents an integer of 1 to 3, but at least one d preferably represents 2 or 3. More preferably, d is an integer of 1 or 2.

[0160] In addition, at least one of Ar 2 and Ar 3 contains a linking carbazole group represented by any one of the formulas (3a) to (3c).

[0161] The general formula (1) is preferably represented by any one of the formulas (6a) to (6c).

[0162] In the formulas (6a) to (6c), Ar 4 , R 1 , R 11 , a and b have the same meanings as in the general formulas (1) and (2). R 12 corresponds to A in the general formula (1). R 1 12 ​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, or a substituted or unsubstituted aromatic hydrocarbon group having 6 to 10 carbon atoms.

[0163] As R 12 When it is an aliphatic hydrocarbon group having 1 to 10 carbon atoms and an unsubstituted group having 6 to 18 carbon atoms, specific examples are the same as those described for the A 1 and R 1 in the above.

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

[0165] d 1 ~d 3 represents the repetition number and independently represents an integer of 1 to 3. Among them, the formulas (6a) to (6c) contain at least one of the linked carbazole structures represented by the formulas (3a) to (3c), and at least one of d 1 ~d 3 is preferably an integer representing 2 or 3.

[0166] k represents the substitution number and independently represents an integer of 0 to 5. k is preferably an integer of 0 to 2. Among them, when R 12 is deuterium, k is preferably an integer of 2 to 5.

[0167] The formula (6a) preferably satisfies any one of the conditions (v) to (vii), and the formula (6b) or (6c) preferably satisfies any one of the conditions (i) to (iv).

[0168] In the A 1 , Ar 2 , Ar 3 and Ar 4 of the general formula (1), preferably at least one contains deuterium, or preferably at least one R 1 is deuterium.

[0169] The compounds of the present invention are suitable as materials for organic EL elements. They are excellent as hosts used in the light-emitting layer of organic EL elements, but can also be used for hole-blocking layers, light-emitting materials, etc.

[0170] The organic EL element of the present invention contains a host selected from the compounds represented by the general formula (1) and the light-emitting dopant.

[0171] The polycyclic aromatic compounds represented by general formula (7a) and general formula (7b) as the luminescent dopant will be described.

[0172] In general formula (7a) and general formula (7b), 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.

[0173] Specific examples of the aromatic ring include rings 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, a benzene ring, a naphthalene ring, an anthracene ring, a triphenylene ring, a phenanthrene ring, a pyrene ring, a pyridine ring, a dibenzofuran ring, a dibenzothiophene ring, or a carbazole ring.

[0174] Y 1 are each independently B, P, P=O, P=S, Al, Ga, As, Si-R 2 or Ge-R 2 , preferably B, P, P=O or P=S, more preferably B.

[0175] R 2 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, 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.

[0176] As specific examples of R 2 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, and the said A 1and R 1 is the same as the description in

[0177] Preferably, it may be exemplified by a group derived from methyl, ethyl, n-propyl, n-butyl, tert-butyl, neopentyl, or cyclohexyl, benzene, naphthalene, anthracene, pyrene, phenanthrene, triphenylene, or fluorene and other aromatic hydrocarbons. More preferably, it may be exemplified by a group derived from benzene or naphthalene.

[0178] As R 2 When it is an unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, the specific examples are the same as the description in the above AR.

[0179] Preferably, it may be exemplified by a group derived from thiophene, benzothiophene, dibenzothiophene, furan, benzofuran, dibenzofuran, or carbazole. More preferably, it may be exemplified by a group derived from dibenzothiophene, dibenzofuran, or carbazole.

[0180] X 1 are each independently O, N-Ar 5 , S or Se, preferably O, N-Ar 5 or S, more preferably O or N-Ar 5 .

[0181] Ar 5 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 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 12 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to four of these aromatic rings. Further preferably, it is a substituted or unsubstituted aromatic hydrocarbon group having 6 to 10 carbon atoms.

[0182] As Ar 5 When it is an unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, the specific examples are the same as the description in the above A 1 in.

[0183] Preferably, it may be exemplified by a group derived from benzene, naphthalene, anthracene, pyrene, phenanthrene, triphenylene, or fluorene. More preferably, it may be exemplified by a group derived from benzene or naphthalene.

[0184] As Ar 5 When it is an unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, the specific examples are the same as the description in the above A1 is the same as the description in

[0185] Preferably, groups generated from thiophene, benzothiophene, dibenzothiophene, furan, benzofuran, dibenzofuran, or carbazole can be enumerated. More preferably, groups generated from dibenzothiophene, dibenzofuran, or carbazole can be enumerated.

[0186] As Ar 5 Specific examples when it is an unsubstituted linking aromatic group are the same as those of A 1 in the case of

[0187] N-Ar 5 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.

[0188] R 3 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.

[0189] As R 3Specific 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, dibenzofuranyl biphenylamino, dibenzofuranyl naphthylamino, dibenzofuranyl anthrylamino, dibenzofuranyl phenanthrylamino, dibenzofuranyl pyrenylamino, bisdibenzofuranylamino, carbazolylphenylamino, carbazolyl naphthylamino, carbazolyl anthrylamino, carbazolyl phenanthrylamino, carbazolyl pyrenylamino, 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.

[0190] As R 3 Specific examples of 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 description of the above A 1 and R 1 are the same.

[0191] Preferred examples include methyl, ethyl, n-propyl, n-butyl, tert-butyl, neopentyl, cyclohexyl, or a group derived from benzene, naphthalene, anthracene, pyrene, phenanthrene, triphenylene, fluorene, etc. More preferred examples include a group derived from benzene or naphthalene.

[0192] As R 3 Specific examples of an unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms are the same as the description in the above A 1 are the same.

[0193] Preferred examples include a group derived from thiophene, benzothiophene, dibenzothiophene, furan, benzofuran, dibenzofuran, or carbazole. More preferred examples include a group derived from dibenzothiophene, dibenzofuran, or carbazole.

[0194] p to t represent the number of substituents. p and q each independently represent an integer of 0 to 4, preferably an integer of 0 to 2, more preferably 0 to 1. r and s each independently represent an integer of 0 to 3, preferably an integer of 0 to 2, more preferably 0 to 1. t represents an integer of 0 to 2, preferably 0 to 1.

[0195] As a preferred form of the polycyclic aromatic compound represented by the general formula (7a) or the general formula (7b), a boron-containing polycyclic aromatic compound represented by the formula (8a) or the formula (8b) can be mentioned.

[0196] In the general formula (8a) and the general formula (8b), X 2 each independently represents N-Ar 5 , O, or S, provided that at least one X 2 represents N-Ar 5 . In addition, the symbols common to the general formula (7a) or the general formula (7b) have the same meanings.

[0197] 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.

[0198] In the general formula (9), Z is a group containing an indolocarbazole ring represented by the formula (10), * is a bond node, and is bonded to L 1 . Ring A is a heterocyclic ring represented by the 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).

[0199] [Chemical formula 24]

[0200]

[0201] L 1 and L 2 each independently is 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 represents 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 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.

[0202] 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 those described in A 1 above.

[0203] Preferably, groups derived from benzene, naphthalene, anthracene, pyrene, phenanthrene, triphenylene, or fluorene can be mentioned. More preferably, groups derived from benzene or naphthalene can be mentioned. L 1 is a v 1 +v 2 valent group, and L 2 is a w + 1 valent group.

[0204] As L 1 and L 2 When it is an unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, it is the same as the description in A 1 above.

[0205] 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.

[0206] Ar 6 and Ar 7 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. Preferred 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 preferred 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.

[0207] As Ar 6 and Ar 7 When it is an unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, it is the same as the description in A 1 above.

[0208] Preferred examples include groups derived from benzene, naphthalene, anthracene, pyrene, phenanthrene, triphenylene, or fluorene. More preferred examples include groups derived from benzene or naphthalene.

[0209] As Ar 6 and Ar 7 When it is an unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, it is the same as the description in A 1 above.

[0210] 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.

[0211] As Ar 6 and Ar 7 When it is an unsubstituted linked aromatic group, it is the same as the case of A 1 above.

[0212] 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, 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 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.

[0213] As R 5 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 description in A 1 and R 1 in the description.

[0214] Preferably, examples include methyl, ethyl, n-propyl, n-butyl, tert-butyl, neopentyl, cyclohexyl, or groups derived from benzene, naphthalene, anthracene, pyrene, phenanthrene, triphenylene, fluorene, etc. More preferably, examples include groups derived from benzene or naphthalene.

[0215] As R 5 Specific examples when it is an unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms are the same as the description in A 1 in the description.

[0216] 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.

[0217] v 1 , v 2 , u 1 , u 2 , u 3 and w represent the number of substitutions. v1 represents an integer of 1 to 3, preferably represented by 1 or 2. v2 represents an integer of 0 to 3, preferably 1 or 2, more preferably represented by 1. u 1 and u 3 each independently represent an integer of 0 to 4, preferably represented by an integer of 0 to 2. u 2 represents an integer of 0 to 2, preferably represented by 0 or 1. w represents an integer of 0 to 3, preferably represented by 0 to 2.

[0218] In the general formulas (9a) and (9b), the notations common to the general formula (9) have the same meanings. X 4 represents O or S.

[0219] R 6Each 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. Preferably, it is 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.

[0220] As R 6 Specific examples when it is an aliphatic hydrocarbon group having 1 to 10 carbon atoms and an unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms are the same as the description in the above R 1 above.

[0221] Preferred 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 preferred examples include a group derived from benzene or naphthalene.

[0222] As R 6 Specific examples when it is an unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms are the same as the description in the above A 1 above.

[0223] Preferred examples include a group derived from thiophene, benzothiophene, dibenzothiophene, furan, benzofuran, dibenzofuran, or carbazole. More preferred examples include a group derived from dibenzothiophene, dibenzofuran, or carbazole.

[0224] Next, the compound represented by the general formula (12) will be described. In addition, the general formula (12) is preferably represented by the following general formula (121).

[0225] [Chemical formula 25]

[0226]

[0227] Ar 8 and Ar 9Each 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 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.

[0228] As Ar 8 and 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 A 1 above.

[0229] Preferably, examples include groups derived from benzene, naphthalene, anthracene, pyrene, phenanthrene, triphenylene, or fluorene. More preferably, examples include groups derived from benzene or naphthalene.

[0230] As Ar 8 and Ar 9 When it is an unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, the specific examples are the same as those described in A 1 above.

[0231] 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.

[0232] As Ar 8 and Ar 9 When it is an unsubstituted linked aromatic group, the specific examples are the same as in the case of A 1 above.

[0233] Each R independently represents deuterium or an aliphatic hydrocarbon group having 1 to 10 carbon atoms.

[0234] When R is an aliphatic hydrocarbon group having 1 to 10 carbon atoms, the specific examples are the same as those described in R 1 above.

[0235] Preferably, examples include methyl, ethyl, n-propyl, n-butyl, tert-butyl, neopentyl, or cyclohexyl.

[0236] e 1 ~e 4 represents the number of substitutions. e 1 and e4 represents an integer from 0 to 4, preferably an integer from 0 to 2. e 2 and e 3 represents an integer from 0 to 3, preferably an integer from 0 to 2.

[0237] Next, the compound represented by the general formula (13) will be described.

[0238] In the general formula (13), Ar 10 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.

[0239] As Ar 10 When it is an unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, the specific examples are the same as those described in A 1 above.

[0240] Preferably, examples include groups derived from benzene, naphthalene, anthracene, pyrene, phenanthrene, triphenylene, or fluorene. More preferably, examples include groups derived from benzene or naphthalene.

[0241] As Ar 10 When it is an unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, the specific examples are the same as those described in A 1 above.

[0242] 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.

[0243] As Ar 10 When it is an unsubstituted linked aromatic group, except for being formed by linking two to eight, the specific examples are the same as those described in A 1 above.

[0244] R 7Each 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, 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.

[0245] 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 those described in R 1 above.

[0246] Preferred examples include methyl, ethyl, n-propyl, n-butyl, tert-butyl, neopentyl, cyclohexyl, or a group derived from benzene, naphthalene, anthracene, pyrene, phenanthrene, triphenylene, fluorene, etc. More preferred examples include a group derived from benzene or naphthalene.

[0247] As R 7 Specific examples when it is an unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms are the same as those described in A 1 above.

[0248] Preferred examples include a group derived from thiophene, benzothiophene, dibenzothiophene, furan, benzofuran, dibenzofuran, or carbazole. More preferred examples include a group derived from dibenzothiophene, dibenzofuran, or carbazole.

[0249] 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. 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.

[0250] 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 those described in R 1 above, respectively.

[0251] Among them, preferred 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 preferred examples include a group derived from benzene or naphthalene.

[0252] f 1 ~f4 represents a substitution number. f 3 and f 4 independently represent an integer from 0 to 4, preferably represented by an integer from 0 to 2. f 1 and f 2 independently represent an integer from 0 to 3, preferably represented by an integer from 0 to 2. g represents a repetition number and independently represents an integer from 1 to 4, preferably represented by an integer from 1 to 2. h represents a substitution number and represents an integer of 1 or 2. In the case where h is 2, the general formula (13) may be symmetric or asymmetric.

[0253] In the present specification, a linking 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 branchedly, and the aromatic rings may be the same or different. In the case where it conforms to the linking aromatic group, it is different from a substituted aromatic hydrocarbon group or a substituted aromatic heterocyclic group.

[0254] In 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), A 1 , Ar 1 ~Ar 10 , R, R 11 , R 12 , R 1 ~R 3 , R 5 ~R 7 , R 77 , L 1 , L 2 When they are an aromatic hydrocarbon group, an aromatic heterocyclic group or a linking aromatic group, these may have substituents. As the substituents, deuterium, a cyano group, a triarylsilyl group having 18 to 36 carbon atoms, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, or a diarylamino group having 12 to 44 carbon atoms are preferred. Here, the aliphatic hydrocarbon group having 1 to 10 carbon atoms 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.

[0255] As specific examples of the substituent, the following can be mentioned: deuterium, cyano group, methyl group, ethyl group, propyl group, isopropyl group, butyl group, tert-butyl group, pentyl group, cyclopentyl group, hexyl group, cyclohexyl group, heptyl group, octyl group, nonyl group, decyl group, diphenylamino group, naphthylphenylamino group, dinaphthylamino group, dianthrylamino group, diphenanthrylamino group, dipyrenylamino group, triphenylsilyl group. Preferred examples include: deuterium, cyano group, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, diphenylamino group, naphthylphenylamino group, or dinaphthylamino group.

[0256] In addition, in this specification, hydrogen is understood to be able 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 substituent can be deuterium.

[0257] 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.

[0258] Specific examples of the compound represented by General Formula (1) are shown below, but are not limited to these exemplified compounds.

[0259] [Chemical Formula 26]

[0260]

[0261] [Chemical Formula 27]

[0262]

[0263] [Chemical Formula 28]

[0264]

[0265] [Chemical Formula 29]

[0266]

[0267] [Chemical Formula 30]

[0268]

[0269] [Chemical Formula 31]

[0270]

[0271] [Chemical Formula 32]

[0272]

[0273] [Chemical Formula 33]

[0274]

[0275] [Chemical Formula 34]

[0276]

[0277] [Chemical Formula 35]

[0278]

[0279] [Chemical Formula 36]

[0280]

[0281] [Chemical Formula 37]

[0282]

[0283] [Chemical Formula 38]

[0284]

[0285] [Chemical Formula 39]

[0286]

[0287] [Chemical Formula 40]

[0288]

[0289] [Chemical Formula 41]

[0290]

[0291] [Chemical Formula 42]

[0292]

[0293] [Chemical Formula 43]

[0294]

[0295] [Chemical Formula 44]

[0296]

[0297] [Chemical Formula 45]

[0298]

[0299] [Chemical Formula 46]

[0300]

[0301] [Chemical Formula 47]

[0302]

[0303] [Chemical Formula 48]

[0304]

[0305] [Chemical Formula 49]

[0306]

[0307] [Chemical Formula 50]

[0308]

[0309] [Chemical Formula 51]

[0310]

[0311] [Chemical Formula 52]

[0312]

[0313] [Chemical Formula 53]

[0314]

[0315] [Chemical Formula 54]

[0316]

[0317] [Chemical Formula 55]

[0318]

[0319] [Chemical Formula 56]

[0320]

[0321] [Chemical Formula 57]

[0322]

[0323] Specific examples of the compounds represented by General Formula (7a), General Formula (7b), Formula (8a), or Formula (8b) are shown below, but are not limited to these exemplified compounds.

[0324] [Chemical Formula 58]

[0325]

[0326] [Chemical Formula 59]

[0327]

[0328] [Chemical formula 60]

[0329]

[0330] [Chemical formula 61]

[0331]

[0332] [Chemical formula 62]

[0333]

[0334] [Chemical formula 63]

[0335]

[0336] [Chemical formula 64]

[0337]

[0338] [Chemical formula 65]

[0339]

[0340] [Chemical formula 66]

[0341]

[0342] [Chemical formula 67]

[0343]

[0344] [Chemical formula 68]

[0345]

[0346] [Chemical formula 69]

[0347]

[0348] [Chemical formula 70]

[0349]

[0350] [Chemical formula 71]

[0351]

[0352] [Chemical formula 72]

[0353]

[0354] [Chemical formula 73]

[0355]

[0356] [Chemical Formula 74]

[0357]

[0358] Specific examples of the compound represented by the general formula (9) are shown below, but are not limited to these exemplified compounds.

[0359] [Chemical Formula 75]

[0360]

[0361] [Chemical Formula 76]

[0362]

[0363] [Chemical Formula 77]

[0364]

[0365] [Chemical Formula 78]

[0366]

[0367] [Chemical Formula 79]

[0368]

[0369] [Chemical Formula 80]

[0370]

[0371] [Chemical Formula 81]

[0372]

[0373] [Chemical Formula 82]

[0374]

[0375] [Chemical Formula 83]

[0376]

[0377] [Chemical Formula 84]

[0378]

[0379] [Chemical Formula 85]

[0380]

[0381] [Chemical Formula 86]

[0382]

[0383] [Chemical formula 87]

[0384]

[0385] [Chemical formula 88]

[0386]

[0387] [Chemical formula 89]

[0388]

[0389] [Chemical formula 90]

[0390]

[0391] [Chemical formula 91]

[0392]

[0393] [Chemical formula 92]

[0394]

[0395] [Chemical formula 93]

[0396]

[0397] [Chemical formula 94]

[0398]

[0399] [Chemical formula 95]

[0400]

[0401] [Chemical formula 96]

[0402]

[0403] [Chemical formula 97]

[0404]

[0405] Specific examples of the compound represented by the general formula (12) are shown below, but are not limited to these exemplified compounds.

[0406] [Chemical formula 98]

[0407]

[0408] [Chemical formula 99]

[0409]

[0410] [Chemical formula 100]

[0411]

[0412] [Chemical Formula 101]

[0413]

[0414] [Chemical Formula 102]

[0415]

[0416] [Chemical Formula 103]

[0417]

[0418] [Chemical Formula 104]

[0419]

[0420] [Chemical Formula 105]

[0421]

[0422] [Chemical Formula 106]

[0423]

[0424] [Chemical Formula 107]

[0425]

[0426] Specific examples of the compound represented by the general formula (13) are shown below, but are not limited to these exemplified compounds.

[0427] [Chemical Formula 108]

[0428]

[0429] [Chemical Formula 109]

[0430]

[0431] [Chemical Formula 110]

[0432]

[0433] [Chemical Formula 111]

[0434]

[0435] [Chemical Formula 112]

[0436]

[0437] [Chemical Formula 113]

[0438]

[0439] [Chemical Formula 114]

[0440]

[0441] [Chemical Formula 115]

[0442]

[0443] [Chemical Formula 116]

[0444]

[0445] [Chemical Formula 117]

[0446]

[0447] [Chemical Formula 118]

[0448]

[0449] [Chemical Formula 119]

[0450]

[0451] [Chemical Formula 120]

[0452]

[0453] [Chemical Formula 121]

[0454]

[0455] [Chemical Formula 122]

[0456]

[0457] [Chemical Formula 123]

[0458]

[0459] [Chemical Formula 124]

[0460]

[0461] [Chemical Formula 125]

[0462]

[0463] 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 of the organic EL element of the present invention preferably have ΔEST of 0.20 eV or less. More preferably, it is 0.15 eV or less, and still more preferably 0.10 eV or less.

[0464] 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 methods described in the examples.

[0465] 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 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.

[0466] 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.

[0467] 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 refers to either one or both of the hole injection layer and the hole transport layer, and the electron injection / transport layer refers to either one or both of the electron injection layer and the electron transport layer.

[0468] It can also be Figure 1 the opposite structure, that is, a cathode 7, an electron transport layer 6, a light-emitting layer 5, a hole transport layer 4, a hole injection layer 3, and an anode 2 are sequentially stacked on the substrate 1. In this case, layers can be added or omitted as needed.

[0469] - Substrate -

[0470] 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 conventionally used for organic EL elements. For example, substrates including glass, transparent plastics, quartz, etc. can be used.

[0471] - Anode -

[0472] As the anode material in the organic EL element, a material containing a metal, alloy, conductive compound having a large work function (4 eV or more) or a mixture thereof 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 be formed by methods such as evaporation or sputtering to form a thin film of these electrode materials, and the desired pattern can be formed by photolithography. 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 in the case of using a substance that can be coated such as an organic conductive compound, wet film formation methods such as printing and coating methods can also be used. When light is emitted from the anode, it is desirable that the transmittance is greater than 10%, and in addition, the sheet resistance of the anode is preferably several hundred Ω / square 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.

[0473] - Cathode -

[0474] 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 and durability against oxidation and the like, a mixture of an electron-injecting metal and a second metal that is a metal with a larger and more stable work function value than it is suitable, such as 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 methods such as evaporation or sputtering. In addition, as the cathode, the sheet resistance is preferably several hundred Ω / square or less, and the film thickness is generally selected in the range of 10 nm to 5 μm, preferably 50 nm to 200 nm. Furthermore, in order for the emitted light to pass through, if either the anode or the cathode of the organic EL element is transparent or translucent, the luminous brightness is increased, which is suitable.

[0475] 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. By applying the above method, an element in which both the anode and the cathode have permeability can be fabricated.

[0476] -Light-emitting layer-

[0477] 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.

[0478] Regarding the light-emitting dopant and the host, for example, they can be used in such a way that the light-emitting dopant is 0.10% to 10% and the host is 99.9% to 90%. It is preferably that the light-emitting dopant is 1.0% to 5.0% and the host is 99% to 95%, and more preferably that the light-emitting dopant is 1.0% to 3.0% and the host is 99% to 97%.

[0479] In this specification, unless otherwise specified, % is mass %.

[0480] As the host in the light-emitting layer, the general formula (1) of the compound of the present invention can be used. In addition, when 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 preferably 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%.

[0481] 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.

[0482] As the other known hosts that can be used, compounds having hole-transporting ability, electron-transporting 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. In addition, 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.

[0483] As the other hosts, they are well known from a large number of patent documents and the like, 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, polyphenylene vinyl derivatives, polyfluorene derivatives and other polymer compounds, etc.

[0484] When 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, whereby multiple hosts can be simultaneously vapor-deposited from one vapor-deposition source.

[0485] As a premixing method, a method that can mix 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.

[0486] The form of the premix can be powder, rod-shaped, or granular.

[0487] 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.

[0488] 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.

[0489] 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.

[0490] 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.

[0491] The phosphorescent dopant material is not particularly limited, and specific examples are as follows.

[0492] [Chemical formula 126]

[0493]

[0494] [Chemical formula 127]

[0495]

[0496] [Chemical formula 128]

[0497]

[0498] [Chemical formula 129]

[0499]

[0500] 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 combined with a light-emitting dopant containing other compounds 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 preferably 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.

[0501] When the light-emitting layer contains two or more light-emitting dopants, the first dopant may be the polycyclic aromatic compound material or the fluorescent light-emitting dopant represented by the general formula (7a), the general formula (7b), the general formula (8a), and the general formula (8b), and a known compound may be used in combination as the light-emitting dopant in the second dopant. As its content, 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.

[0502] 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, bisstyryl anthracene derivatives or bisstyryl benzene derivatives such as bisstyryl derivatives, bisstyryl arylene 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.

[0503] 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.

[0504] - Injection layer -

[0505] 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.

[0506] - Hole blocking layer -

[0507] Broadly speaking, the so-called hole blocking layer has the function of an electron transport layer, includes a hole blocking material having the function of transporting electrons and significantly small ability to transport holes, and 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 second host can also be used as the material of the hole blocking layer. In addition, multiple hole blocking materials can also be used in combination.

[0508] - Electron blocking layer -

[0509] The so-called electron blocking layer, in a broad sense, 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 first 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.

[0510] -Exciton blocking layer-

[0511] The so-called exciton blocking layer is a layer for blocking 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 confined 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.

[0512] As the material for the exciton blocking layer, known exciton blocking layer materials can be used.

[0513] 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.

[0514] -Hole transport layer-

[0515] 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.

[0516] As the hole transport material, it is a material having either the function of injecting or transporting holes or the function of blocking electrons, 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. can be cited. It is preferably to use porphyrin derivatives, arylamine derivatives, and styrylamine derivatives, and more preferably to use arylamine derivatives.

[0517] -Electron transport layer-

[0518] 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.

[0519] 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, aluminum(III) tris(8-hydroxyquinoline) 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.

[0520] The film forming 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.

[0521] Examples

[0522] Calculation examples

[0523] Calculation of HOMO and LUMO values

[0524] For the compounds 1-1, 1-12, 1-13, 1-29, 1-46, 1-82, 1-86, 1-118, 1-128, 1-129, 1-153, 1-160, and 1-177, the 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 the 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.

[0525] [Table 1]

[0526] Compound HOMO (eV) LUMO (eV) 1-1 -5.1 -2.0 1-12 -5.2 -1.8 1-13 -5.3 -2.1 1-29 -5.2 -2.0 1-46 -5.3 -2.0 1-82 -5.3 -1.9 1-86 -5.1 -2.1 1-118 -5.2 -1.7 1-128 -5.0 -1.9 1-129 -5.1 -1.9 1-153 -5.3 -2.0 1-160 -5.2 -2.0 1-177 -5.3 -2.0

[0527] Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited to these examples.

[0528] First, as representative examples, synthesis examples of compounds 1-1, 1-118, 1-177, and 1-217 are shown. For other compounds, they are also synthesized by similar methods.

[0529] Synthesis Example 1 (Synthesis of Compound 1-1)

[0530] [Chemical Formula 130]

[0531]

[0532] Charge T1 (21.0 mmol), T2 (25.2 mmol), and cesium carbonate (63.0 mmol) into a 500 ml three-necked flask purged with degassed nitrogen. After adding 210 ml of N,N-dimethyl acetamide (DMAc) thereto, stir at 160 °C for 17 hours. After temporarily cooling to room temperature, add 200 ml of water and 400 mL of toluene, transfer to a separatory funnel, and separate into an organic layer and an aqueous layer. Wash the organic layer three times with 200 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 78%.

[0533] [Chemical Formula 131]

[0534]

[0535] Add T3 (18.1 mmol) and 180 ml of dehydrated tetrahydrofuran to a 300 mL three-necked flask purged with degassed nitrogen. While stirring at -78 °C, charge n-butyllithium (21.7 mmol), and stir at -78 °C for 1 hour. Then, add triisopropoxyborane (27.1 mmol) at -78 °C, and stir at room temperature for 1 hour. Further add 50 ml of 2M hydrochloric acid, stir for 1 hour, and then add distilled water (200 ml) and toluene (200 ml) while stirring. Wash the organic layer with distilled water (100 ml × 3). After drying the organic layer with anhydrous magnesium sulfate, filter and separate the magnesium sulfate, and distill off the solvent under reduced pressure. Purify the obtained residue by silica gel column chromatography to obtain Compound T4 (white solid). The yield is 85%.

[0536] [Chemical Formula 132]

[0537]

[0538] Into a 500 ml three-necked flask purged with degassed nitrogen, charge T4 (16.6 mmol), T5 (24.9 mmol), tetrakis(triphenylphosphine)palladium(0) (0.5 mmol), and potassium carbonate (49.7 mmol). After adding 170 ml of toluene, 25 ml of ethanol, and 25 ml of water thereto, stir at 100 °C for 5 hours. After temporarily cooling to room temperature, add 100 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 100 ml of water, and then concentrate the obtained organic layer under reduced pressure. Purify the obtained residue by column chromatography to obtain Compound 1-1 (white solid). The yield is 68%. APCI-TOFMS m / z = 729 [M+1] +

[0539] Synthesis Example 2 (Synthesis of Compound 1-118)

[0540] [Chemical Formula 133]

[0541]

[0542] Into a 500 ml three-necked flask purged with degassed nitrogen, charge T4 (16.6 mmol), T6 (24.9 mmol), tetrakis(triphenylphosphine)palladium(0) (0.5 mmol), and potassium carbonate (49.7 mmol). After adding 170 ml of toluene, 25 ml of ethanol, and 25 ml of water thereto, stir at 100 °C for 5 hours. After temporarily cooling to room temperature, add 100 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 100 ml of water, and then concentrate the obtained organic layer under reduced pressure. Purify the obtained residue by column chromatography to obtain Compound 1-118 (white solid). The yield is 70%. APCI-TOFMS m / z = 818 [M+1] +

[0543] Synthesis Example 3 (Synthesis of Compound 1-177)

[0544] [Chemical Formula 134]

[0545]

[0546] Into a 500 ml three-necked flask purged with degassed nitrogen, T7 (16.6 mmol), T8 (20.0 mmol), tetrakis(triphenylphosphine)palladium(0) (0.5 mmol), and potassium carbonate (49.7 mmol) were charged. After adding 250 ml of toluene, 250 ml of ethanol, and 25 ml of water thereto, the mixture was stirred at 100 °C for 7 hours. After temporarily cooling to room temperature, 100 ml of water was added, and the mixture was transferred to a separatory funnel and separated into an organic layer and an aqueous layer. The organic layer was washed three times with 100 ml of water, and then the obtained organic layer was concentrated under reduced pressure. The obtained residue was purified by column chromatography to obtain Compound 1-177 (white solid). The yield was 67%. APCI-TOFMS m / z = 983 [M+1] +

[0547] Synthesis Example 4 (Synthesis of Compound 1-217)

[0548] [Chemical Formula 135]

[0549]

[0550] To 1-118 (10.1 mmol) in a 300 ml three-necked flask purged with degassed nitrogen, 150 mL of deuterated benzene (C6D6) and 9.0 g of deuterated trifluoromethanesulfonic acid (Trifluoromethanesulfonic acid, TfOD) were added, and the mixture was heated and stirred at 50 °C for 6.5 hours in a nitrogen atmosphere. The reaction solution was added to a deuterated aqueous solution (200 mL) of sodium carbonate (7.0 g) and rapidly cooled to obtain a solid. The obtained solid was purified by column chromatography to obtain Compound 1-217 (white solid) (average deuteration rate: 71%). The yield was 37%. APCI-TOFMS m / z = 853 [M+1] +

[0551] The average deuteration rate can be determined by mass analysis or proton nuclear magnetic resonance spectroscopy. For example, in the case of determination 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. The proton concentration [mol / g] of the compound contained in the measurement sample is calculated based on the integral intensity ratio of the internal standard substance and the compound source. 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 1-217, a 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 1-217 (5.0 mg) and dimethyl sulfone (2.0 mg) as an internal standard substance in deuterated tetrahydrofuran (1.0 ml). The average proton concentration [mol / g] of Compound 1-217 contained in the measurement sample is calculated based on the integral intensity ratio of the internal standard substance and Compound 1-217 source. In addition, the average proton concentration [mol / g] is similarly calculated for the non-deuterated form of Compound 1-217 (corresponding to Compound 1-118). Next, the ratio of the proton concentration of Compound 1-217 to the proton concentration of the non-deuterated form of Compound 1-217 is calculated and subtracted from 1, whereby the average deuteration rate of Compound 1-217 is calculated.

[0552] In addition, Compound 1-217 shows an example of the structural formula when all the hydrogens of the compound represented by Formula (1) are deuterated.

[0553] Compounds used in Examples and Comparative Examples are shown below.

[0554] [Chemical Formula 136]

[0555]

[0556] [Chemical Formula 137]

[0557]

[0558] [Chemical Formula 138]

[0559]

[0560] [Chemical Formula 139]

[0561]

[0562] Measure S1 and T1 of Compound 2-2, Compound 4-2, and Compound 4-13.

[0563] S1 and T1 are measured in the following manner.

[0564] On a quartz substrate, using the vacuum evaporation method, under the condition of a vacuum degree of 10 -4 Pa or less, the compound (1-58) 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 where the concentration of the luminescent dopant becomes 3%.

[0565] Regarding S1, the luminescence spectrum of the evaporation film is measured, a tangent line is drawn for the rise on 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.

[0566] S1 [eV] = 1239.85 / λedge (i)

[0567] Regarding T1, the phosphorescence spectrum of the evaporation film is measured, a tangent line is drawn for the rise on 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.

[0568] T1 [eV] = 1239.85 / λedge (ii)

[0569] The measurement results are shown in Table 2.

[0570] [Table 2]

[0571] 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

[0572] Example 1

[0573] On a glass substrate formed with an anode containing ITO with a film thickness of 70 nm, using the vacuum evaporation method with a vacuum degree of 4.0×10 -5Stack the thin films layer by layer. First, form HAT-CN with a thickness of 10 nm as a hole injection layer on ITO. Next, form HT-1 with a thickness of 25 nm as a hole transport layer. Next, form Compound 7-58 with a thickness of 5 nm as an electron blocking layer. Next, co-evaporate Compound 1-1 as the first host, Compound 5-148 as the second host, and Compound 4-2 as a luminescent dopant from different evaporation sources respectively, and form the light-emitting layer with a thickness of 30 nm. At this time, co-evaporation is carried out under the evaporation conditions where the concentration of Compound 4-2 is 2% and the mixing ratio of the first host to the second host is 30:70. Next, form Compound H6 with a thickness of 5 nm as a hole blocking layer. Next, form ET-1 with a thickness of 40 nm as an electron transport layer. Form lithium fluoride (LiF) with a thickness of 1 nm as an electron injection layer on the electron transport layer. Finally, form aluminum (Al) with a thickness of 70 nm as a cathode on the electron injection layer to fabricate an organic EL device.

[0574] Examples 2 to 6, Examples 8 to 10, Examples 12 to 27, Comparative Examples 1 to 15

[0575] 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 are set to the compounds shown in Tables 3 and 4, an organic EL device is fabricated in the same manner as in Example 1. In addition, the mixing ratio is the first host: the second host.

[0576] Examples 7, 11

[0577] 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 are set to the compounds shown in Table 3, an organic EL device is fabricated in the same manner as in Example 6.

[0578] [Table 3]

[0579] 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 1-12 5-148 30：70 H6 Example 3 4-2 1-13 5-148 30：70 H6 Example 4 4-2 1-29 5-148 30：70 H6 Example 5 4-2 1-118 6-2 50：50 H6 Example 6 4-2 1-118 6-4 50：50 H6 Example 7 4-2 1-118 6-4 50：50 1-118 Example 8 4-13 1-118 7-58 30：70 H6 Example 9 4-2 1-118 5-148 30：70 H6 Example 10 4-2 1-118 5-148 40：60 H6 Example 11 4-2 1-86 5-148 30：70 1-118 Example 12 4-2 1-86 5-148 30：70 H6 Example 13 4-2 1-46 5-115 30：70 H6 Example 14 4-2 1-82 5-148 30：70 H6 Example 15 4-2 1-128 5-179 30：70 H6 Example 16 4-2 1-129 5-148 30：70 H6 Example 17 4-2 1-160 5-148 30：70 H6 Example 18 4-2 1-152 5-148 30：70 H6 Example 19 4-2 1-153 5-148 30：70 H6 Example 20 4-2 1-177 5-148 30：70 H6 Example 21 4-2 1-212 5-148 30：70 H6 Example 22 4-2 1-214 5-148 30：70 H6 Example 23 4-2 1-216 5-148 30：70 H6 Example 24 4-2 1-217 5-148 30：70 H6 Example 25 2-2 1-47 7-58 30：70 H6 Example 26 2-2 1-47 7-31 30：70 H6 Example 27 2-2 1-47 7-81 30：70 H6

[0580] [Table 4]

[0581] Luminescent dopant First host Second host Mixing ratio Hole blocking layer 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 H7 5-148 30：70 H6 Comparative Example 7 4-2 H8 5-148 30：70 H6 Comparative Example 8 4-2 H6 5-148 30：70 H6 Comparative Example 9 4-2 H6 6-2 50：50 H6 Comparative Example 10 4-2 H6 6-4 50：50 H6 Comparative Example 11 4-13 H6 7-58 30：70 H6 Comparative Example 12 4-13 H6 mCBP 30：70 H6 Comparative Example 13 2-2 H6 7-58 50：50 H6 Comparative Example 14 2-2 H7 7-58 50：50 H6 Comparative Example 15 4-2 H9 5-148 30：70 H6

[0582] The maximum emission wavelength, external quantum efficiency, and device lifetime of the organic EL devices fabricated in the examples and comparative examples are shown in Tables 5 and 6. The maximum emission wavelength and external quantum efficiency are the values when the current density is 2.5 mA / cm 2 and are the initial characteristics. LT70 is the device lifetime, and the time is measured until the luminance decays to 70% of the initial luminance when the current density is 2.5 mA / cm 2 .

[0583] [Table 5]

[0584]

[0585] [Table 6]

[0586]

[0587] As can be seen from Table 5 and Table 6, the organic EL elements of Examples 1 to 27 have the characteristics of high efficiency and long life compared with the organic EL elements of Comparative Examples 1 to 15, and emit blue light according to the maximum emission wavelength, and thus exhibit excellent characteristics as a host material. It can be seen that when comparing Example 6 with Example 7 and Example 11 with Example 12, the elements using the compound represented by the general formula (1) in the hole blocking layer also exhibit the characteristic of long life compared with known compounds.

[0588] Example 28

[0589] 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 vacuum degree of 4.0×10 -5 Pa. First, HAT-CN is formed on the ITO to a thickness of 10 nm as a hole injection layer, and then HT-1 is formed to a thickness of 25 nm as a hole transport layer. Next, Compound 7-58 is formed to a thickness of 5 nm as an electron blocking layer. Next, Compound 7-58 as a host and Compound 1-118 as a luminescent dopant are co-evaporated from different evaporation sources, and the light-emitting layer is formed to a thickness of 30 nm. At this time, co-evaporation is performed under the evaporation conditions where the concentration of Compound 1-118 becomes 30%. Next, Compound H6 is formed to a thickness of 5 nm as a hole blocking layer. Next, ET-1 is formed to a thickness of 40 nm as an electron transport layer. Further, lithium fluoride (LiF) is formed to a thickness of 1 nm on the electron transport layer as an electron injection layer. Finally, aluminum (Al) is formed to a thickness of 70 nm on the electron injection layer as a cathode, thereby fabricating an organic EL element.

[0590] Comparative Examples 16 and 17

[0591] An organic EL element is fabricated in the same manner as in Example 28 except that the luminescent dopant is the compound shown in Table 7.

[0592] 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 7. The maximum emission wavelength, external quantum efficiency, and L70 are the same as those in Table 3.

[0593] [Table 7]

[0594]

[0595] As can be seen from Table 7, the organic EL element of the embodiment has the characteristics of high efficiency and long life, and emits blue light according to the maximum emission wavelength.

[0596] Example 29

[0597] 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 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, the host compound 1-1 and the light-emitting dopant Ir(ppy)3 are co-evaporated from different evaporation sources, 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 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 as an electron injection layer on the electron transport layer. Finally, Al is formed to a thickness of 70 nm as a cathode on the electron injection layer, thereby fabricating an organic EL element.

[0598] Examples 30 to 46, Comparative Examples 18 to 25

[0599] An organic EL element was fabricated in the same manner as in Example 29 except that the compound shown in Table 8 was used as the host.

[0600] 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 are 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 life.

[0601] [Table 8]

[0602]

[0603] Example 47

[0604] On a glass substrate on which an anode containing ITO with a film thickness of 110 nm is formed, by vacuum evaporation at a vacuum degree of 4.0×10 -5Stack the thin films. First, form HAT-CN on ITO to a thickness of 25 nm as a hole injection layer. Next, form Spiro-TPD to a thickness of 30 nm as a hole transport layer. Next, form HT-2 to a thickness of 10 nm as an electron blocking layer. Next, co-evaporate Compound 1-1 as the first host, Compound 6-2 as the second host, and Ir(ppy)3 as a light-emitting dopant from different evaporation sources respectively, and form the light-emitting layer to a thickness of 40 nm. At this time, co-evaporation is carried out 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, form ET-1 to a thickness of 20 nm as an electron transport layer. Further, form LiF to a thickness of 1 nm as an electron injection layer on the electron transport layer. Finally, form Al to a thickness of 70 nm as a cathode on the electron injection layer, thereby fabricating an organic EL element.

[0605] Examples 48 to 63, Comparative Examples 26 to 33

[0606] 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 9, an organic EL element is fabricated in the same manner as in Example 47.

[0607] The fabricated organic EL element is evaluated in the same manner as in Example 29. The evaluation results are shown in Table 9.

[0608] [Table 9]

[0609]

[0610] From the results of Tables 8 and 9, it can be seen that the lifetimes of the organic EL elements of Examples 29 to 66 are improved compared to those of the comparative examples, showing good characteristics.

[0611] Explanation of reference numerals

[0612] 1: Substrate

[0613] 2: Anode

[0614] 3: Hole injection layer

[0615] 4: Hole transport layer

[0616] 5: Light-emitting layer

[0617] 6: Electron transport layer

[0618] 7: Cathode

Claims

1. A compound represented by the following general formula (1). [Chemical formula 1] Here, A 1 represents hydrogen, 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 four of these aromatic groups. Ar 2 and Ar 3 each independently represents the following formula (2), Ar 4 independently represents the following formula (2), or deuterium. [Chemical formula 2] Here, 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 and b represent substitution numbers, a represents an integer from 0 to 4, and b independently represents an integer from 0 to 7. d represents a repetition number, independently represents an integer from 1 to 3, provided that at least one d represents 2 or 3. * represents the key node of the general formula (1). Among them, Ar 2 and Ar 3 at least one of which contains a linked carbazolyl group represented by the following formula (3a) to formula (3c). [Chemical formula 3] Here, R 1 , b, and * have the same meanings as in the case of the formula (2). c represents the number of substituents and independently represents an integer from 0 to 8.

2. The compound according to claim 1, wherein the general formula (1) is represented by any one of the following formulas (6a) to (6c). [Chemical formula 4] Here, Ar 4 , R 1 , R 11 , a and b have the same meanings as in the general formula (1) and the general formula (2). R 12 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. d 1 to d 3 represent the number of repetitions and independently represent an integer of 1 to 3. k represents the number of substitutions and represents an integer of 0 to 5. Among them, d 2 and d 3 at least one of which represents an integer of 2 or 3 and contains at least one linking carbazolyl group represented by any one of the formulas (3a) to (3c).

3. The compound according to claim 2, wherein, It is a compound represented by any one of the formulas (6a) to (6c). In the compound represented by the formula (6a), any one of the following conditions (v) to (vii) is satisfied. In the compounds represented by the formulas (6b) and (6c), any one of the following conditions (i) to (iv) is satisfied. (i)d 1 = 1, and d 2 = 2 or 3, and d 3 = 1 (ii)d 1 = 1, and d 2 = 1, and d 3 = 2 or 3 (iii)d 1 = 2, and d 2 = 2, and d 3 = 1 (iv)d 1 = 1, and d 2 = 2, and d 3 = 2 (v)d 2 = 1, and d 3 = 2 or 3 (vi)d 2 = 2 or 3, and d 3 = 1 (vii)d 2 = 2, and d 3 = 2.

4. The compound according to claim 1, characterized in that, Ar 4 is deuterium.

5. The compound according to claim 1, wherein The compound represented by the general formula (1) contains at least one deuterium.

6. The compound according to claim 1, wherein A 1 、 Ar 2 、 Ar 3 and Ar 4 at least one of which is a group having deuterium.

7. The compound according to claim 6, characterized in that, A 1 and Ar 2 at least one of which is a group having deuterium.

8. The compound according to claim 6, characterized in that, Ar 3 is a group having at least one deuterium.

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

10. An organic electroluminescent element includes more than one light-emitting layer between an opposing anode and cathode. The organic electroluminescent element 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.

11. The organic electroluminescent device according to claim 10, 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 5] 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. Y 1 are each independently B, P, P=O, P=S, Al, Ga, As, Si-R 2 or Ge-R 2 , R 2 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, X 1 are each independently O, N-Ar 5 , S or Se, Ar 5 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, N-Ar 5 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 3 each independently represents cyano, 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. p to t represent the number of substitutions. p and q each independently represent an integer of 0 to 4, r and s each independently represent an integer of 0 to 3, and t represents an integer of 0 to 2.

12. The organic electroluminescent device according to claim 11, wherein The polycyclic aromatic compound represented by the general formula (7a) or general formula (7b) is a polycyclic aromatic compound represented by the following formula (8a) or formula (8b). [Chemical formula 6] Here, X 2 independently represents N-Ar 5 , O, or S, provided that at least one X 2 represents N-Ar 5 . Ar 5 , R 3 have the same meanings as in the case of the general formula (7a) or general formula (7b).

13. The organic electroluminescent element according to claim 10, 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.

14. The organic electroluminescent element according to claim 13, wherein The ΔEST is 0.10 eV or less.

15. The organic electroluminescent device according to claim 10, wherein The light-emitting dopant is a phosphorescent light-emitting dopant.

16. The organic electroluminescent device according to any one of claims 10 to 15, wherein Contains a first host selected from the compounds represented by the general formula (1), a light-emitting dopant, and a second host.

17. The organic electroluminescent device according to claim 16, wherein The second host is selected from the compounds represented by the following general formula (9), or is selected from the compounds represented by the general formula (9a) or general formula (9b). [Chemical formula 7] Here, Z is a group containing an indolocarbazole ring represented by the formula (10), and * is a bond node. Ring A is a heterocycle represented by formula (11), and ring A is condensed with the adjacent ring at any position. 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 6 and Ar 7 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. R 5 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. v 1 ~v 2 、u 1 ~u 3 and w represent substitution numbers, v 1 represents an integer from 1 to 3, v 2 represents an integer from 0 to 3, u 1 and u 3 each independently represents an integer from 0 to 4, u 2 represents an integer from 0 to 2, and w represents an integer from 0 to 3. [Chemical formula 8] Z, Ar 6 , v 1 and v 2 have the same meaning as in general formula (9), 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.

18. The organic electroluminescent element according to claim 16, wherein The second host is selected from the compounds represented by the following general formula (12) or general formula (13). [Chemical formula 9] Here, Ar 8 , and Ar 9 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 aromatic rings of these aromatic groups. R each independently represents deuterium or an aliphatic hydrocarbon group having 1 to 10 carbon atoms. e 1 ~e 4 represents the substitution number, e 1 and e 4 represents an integer from 0 to 4, e 2 and e 3 represents an integer from 0 to 3. [Chemical formula 10] Here, Ar 10 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 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. f 1 ~f 4 represent the substitution number, f 3 and f 4 independently represent an integer from 0 to 4, f 1 and f 2 independently represent an integer from 0 to 3. g represents the repetition number and independently represents an integer from 1 to 4. h represents the substitution number and represents an integer of 1 or 2. When h is 2, the general formula (13) can be symmetric or asymmetric.

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