Polycyclic aromatic compound, organic electroluminescent element, display device, and lighting device

Abstract

[Problem] To provide a polycyclic aromatic compound, an organic electroluminescent element, a display device, and a lighting device. [Solution] A polycyclic aromatic compound having a structure including one or more structural units represented by formula (1): wherein the definition of formula (1) is the same as described in the embodiment. # imgabs0 #

Description

Technical Field

[0001] The present invention relates to polycyclic aromatic compounds and also to organic devices such as organic electroluminescent elements, organic field effect transistors and organic thin film solar cells, as well as display devices and lighting devices using the polycyclic aromatic compounds. Background Art

[0002] In the past, display devices using light-emitting elements that perform electroluminescence have been studied in various ways because they can achieve power saving or thinning. In addition, organic electroluminescent elements containing organic materials have been actively studied because they can easily achieve light weight or large size. In particular, the development of organic materials having light-emitting properties such as blue or green, which are one of the three primary colors of light, and the development of organic materials having charge transport capabilities such as holes and electrons (having the possibility of becoming semiconductors or superconductors) have been actively studied so far, whether they are polymer compounds or low molecular weight compounds.

[0003] An organic electroluminescence (EL) element has a structure including a pair of electrodes consisting of an anode and a cathode, and one or more layers disposed between the pair of electrodes and containing an organic compound. The layer containing the organic compound includes a light-emitting layer or a charge transport / injection layer for transporting or injecting charges such as holes and electrons, and various organic materials suitable for these layers have been developed.

[0004] Among them, Patent Documents 1 to 3 disclose that polycyclic aromatic compounds containing boron are useful as materials for organic electroluminescent devices, etc. Organic electroluminescent devices containing such polycyclic aromatic compounds are reported to have good external quantum efficiency.

[0005] [Prior art literature]

[0006] [Patent Document]

[0007] (Patent Document 1) International Publication No. 2015 / 102118

[0008] (Patent Document 2) Korean Patent Publication No. 10-2022-0069866

[0009] (Patent Document 3) U.S. Patent Application Publication No. 2021 / 0143331 Summary of the invention

[0010] [Problems to be solved by the invention]

[0011] As described above, various materials have been developed as materials for organic EL elements. However, in order to increase the choice of materials for organic EL elements, it is desired to develop a material including a compound different from conventional ones.

[0012] An object of the present invention is to provide a novel compound useful as a material for organic devices such as organic EL elements.

[0013] [Technical means to solve the problem]

[0014] The present inventors have made intensive researches to solve the above problems and have found that polycyclic aromatic compounds capable of manufacturing organic EL devices with higher efficiency and longer life are obtained among compounds having a structure containing boron as in the compounds described in Patent Documents 1 to 3, thereby completing the present invention. That is, the present invention provides the following polycyclic aromatic compounds, and further provides materials for organic devices containing the following polycyclic aromatic compounds.

[0015] <1> A polycyclic aromatic compound having a structure including one or more structural units represented by the following formula (1):

[0016]

[0017] In formula (1),

[0018] Ring A, Ring B and Ring C are each independently a substituted or unsubstituted aryl ring, or a substituted or unsubstituted heteroaryl ring,

[0019] However, at least one selected from the group consisting of Ring A, Ring B and Ring C is a ring having at least the formula (E ABC ) as a substituent or an aromatic ring having at least ABC ) as a substituent of a heteroaryl ring,

[0020] J are each independently a group represented by formula (1Ar) or formula (2Ar), and at least one J is a group represented by formula (1Ar),

[0021] Formula (E ABC )middle,

[0022] * indicates the bonding position to the aryl ring or heteroaryl ring,

[0023] The P ring and the Q ring are each independently a substituted or unsubstituted aryl ring, or a substituted or unsubstituted heteroaryl ring,

[0024] In formula (1Ar) and formula (2Ar),

[0025] # indicates the bonding position with nitrogen,

[0026] The D ring and the E ring are each independently a substituted or unsubstituted aryl ring, or a substituted or unsubstituted heteroaryl ring,

[0027] In formula (1Ar),

[0028] G are the same or different and are hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted arylthio, substituted or unsubstituted heteroarylthio, substituted or unsubstituted aryloxy, substituted or unsubstituted heteroaryloxy, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, or substituted or unsubstituted silyl, at least one G is substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted arylthio, substituted or unsubstituted heteroarylthio, substituted or unsubstituted aryloxy, substituted or unsubstituted heteroaryloxy, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, or substituted or unsubstituted silyl,

[0029] Substituents substituted at adjacent atoms in the aryl ring and heteroaryl ring of the structure may be bonded to each other to form a ring.

[0030] In the structure, at least one of the aryl ring and the heteroaryl ring may be condensed into at least one cycloalkane, the cycloalkane may have a substituent, and at least one -CH2- in the cycloalkane may be substituted by -O-,

[0031] At least one hydrogen in the structure may be replaced by a cyano group or a halogen,

[0032] At least one hydrogen in the structure may be replaced by deuterium, and at least one nitrogen may be replaced by 15 nitrogen( 15 N) substituted, at least one sulfur may be 33 sulfur( 33 S), 34 sulfur( 34 S) or 36 sulfur( 36 S) substituted, at least one oxygen may be 17 oxygen( 17 O) or 18 oxygen( 18 O) substitution, at least one carbon may be 13 carbon( 13 C) substituted, and at least one boron may be 11 boron( 11 B) Replacement.

[0033] <2> according to <1> The polycyclic aromatic compound is characterized in that the A ring, B ring, C ring, D ring, E ring, P ring and Q ring are independently a substituted or unsubstituted aryl ring with 6 to 16 carbon atoms, or a substituted or unsubstituted heteroaryl ring with 2 to 15 carbon atoms.

[0034] <3> according to <2> The polycyclic aromatic compound is characterized in that the A ring, the B ring, the C ring, the D ring and the E ring are independently a substituted or unsubstituted aryl ring, or a substituted or unsubstituted heteroaryl ring,

[0035] The aryl ring is selected from the group consisting of a benzene ring, a biphenyl ring, an indene ring, a naphthalene ring, a fluorene ring, an anthracene ring and a phenanthrene ring,

[0036] The heteroaryl ring is selected from the group consisting of a benzofuran ring, a benzothiophene ring, an indole ring, a dibenzofuran ring, a dibenzothiophene ring, a carbazole ring, a naphthofuran ring, a naphthothiophene ring, a benzindole ring, a benzoselenophene ring, a dibenzoselenophene ring, a silaindene ring and a silafluorene ring.

[0037] <4> according to <1> The polycyclic aromatic compound is characterized by the formula (E ABC ) is given by the following formula (E ABC -1), formula (E ABC -2), formula (E ABC -3), formula (E ABC -4) or formula (E ABC -5) means:

[0038]

[0039] Formula (E ABC -1), formula (E ABC -2), formula (E ABC -3), formula (E ABC -4) and formula (E ABC -5),

[0040] Z E are independently -C(-R ZE )=or-N=,R ZE is hydrogen, halogen, cyano, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl,

[0041] Z X are independently -C(-R ZX )=or-N=,R ZXis hydrogen, halogen, cyano, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl,

[0042] Y 1 >NR NY 、>C(-R CY )2、>O、>Si(-R IY 2. PR PY 、>P(=O)R POY ,>S,>SO,>SO2 or>Se,

[0043] R NY , R CY , R IY , R PY and R POY are each independently hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl, and both R CY Can bond to each other to form a ring, two R IY They may bond to each other to form a ring.

[0044] <5> according to <1> The polycyclic aromatic compound is characterized in that formula (1) is represented by formula (1X1):

[0045]

[0046] In the formula (1X1),

[0047] J is the same as J in formula (1),

[0048] R a is hydrogen or unsubstituted alkyl,

[0049] R b The same or different, and at least one R b Formula (E ABC ).

[0050] <6> according to <5> The polycyclic aromatic compound is characterized in that R b are independently of the formula (E ABC -1), formula (E ABC -2), formula (E ABC -3), formula (E ABC -4) or formula (E ABC -5).

[0051] <7> A polycyclic aromatic compound, wherein J is independently a group represented by the following formula (1Ar-1) or formula (2Ar-1):

[0052]

[0053] In formula (1Ar-1) and formula (2Ar-1),

[0054] R e are each independently hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted aryl, or substituted or unsubstituted silyl,

[0055] R d are each independently hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, or substituted or unsubstituted aryl,

[0056] R dd is hydrogen, or substituted or unsubstituted aryl,

[0057] In the formula (1Ar-1),

[0058] G's are the same or different and are hydrogen, unsubstituted alkyl, haloalkyl, unsubstituted cycloalkyl, unsubstituted aryl, or unsubstituted heteroaryl, and at least one G is unsubstituted alkyl, haloalkyl, unsubstituted cycloalkyl, unsubstituted aryl, or unsubstituted heteroaryl.

[0059] <8> according to <1> In the polycyclic aromatic compound, J is independently represented by formula (1Ar).

[0060] <9> according to <1> The polycyclic aromatic compound is represented by any of the following formulas:

[0061]

[0062]

[0063]

[0064] <10> An organic electroluminescent element comprises a pair of electrodes consisting of a positive electrode and a negative electrode and an organic layer arranged between the pair of electrodes, wherein the organic layer contains <1> to <9> The polycyclic aromatic compound described in any one of the above.

[0065] <11> according to <10> The organic electroluminescent element is characterized in that the organic layer is a light-emitting layer.

[0066] <12> according to <11> The organic electroluminescent element is characterized in that the light-emitting layer comprises at least one selected from the group consisting of an assisting dopant and a phosphorescent material.

[0067] <13> A display device or lighting device, comprising <10> The organic electroluminescent element.

[0068] [Effects of the Invention]

[0069] According to the present invention, there is provided a novel polycyclic aromatic compound useful as a material for organic devices such as organic electroluminescent elements. The polycyclic aromatic compound of the present invention can be used to produce organic devices such as organic electroluminescent elements. BRIEF DESCRIPTION OF THE DRAWINGS

[0070] Figure 1 This is a schematic cross-sectional view showing an example of an organic electroluminescent element.

[0071] [Explanation of Symbols]

[0072] 100: organic electroluminescent element;

[0073] 101: Substrate;

[0074] 102: anode;

[0075] 103: hole injection layer;

[0076] 104: hole transport layer;

[0077] 105: luminous layer;

[0078] 106: electron transport layer;

[0079] 107: electron injection layer;

[0080] 108: cathode. DETAILED DESCRIPTION

[0081] Hereinafter, the present invention will be described in detail. Although the description of the constituent conditions described below is based on representative embodiments or specific examples, the present invention is not limited to such embodiments. In addition, in this specification, the numerical range represented by "to" refers to a range including the numerical values ​​recorded before and after "to" as the lower limit and the upper limit. In addition, in this specification, "hydrogen" in the structural formula description means "hydrogen atom (H)". Similarly, "carbon atom (C)" is sometimes referred to as "carbon".

[0082] In the present specification, "adjacent groups" refers to two groups respectively bonded to two adjacent atoms (two atoms directly bonded by a covalent bond) in a structural formula.

[0083] In the present specification, "Me" represents a methyl group, "Et" represents an ethyl group, "nBu" represents a normal-butyl group, "tBu" represents a tertiary butyl group, "iBu" represents an isobutyl group, "secBu" represents a sec-butyl group, "nPr" represents a normal-propyl group, "iPr" represents an isopropyl group, "tAm" represents a tert-amyl group, "2EH" represents a 2-ethylhexyl group, "tOct" represents a tert-octyl group, "Ph" represents a phenyl group, "Mes" represents mesityl (2,4,6-trimethylphenyl), "Ad" represents a 1-adamantyl group, "Tf" represents a trifluoromethanesulfonyl group, "TMS" represents a trimethylsilyl group, and "D" represents a deuterium group.

[0084] In this specification, an organic electroluminescent element may be referred to as an organic EL element.

[0085] In this specification, although the chemical structure or substituent is sometimes represented by the carbon number, in the case where the chemical structure is substituted by a substituent or the substituent is further substituted by a substituent, the carbon number refers to the carbon number of each chemical structure or substituent, and does not mean the total carbon number of the chemical structure and the substituent or the total carbon number of the substituent and the substituent. For example, "substituent B with carbon number Y replaced by substituent A with carbon number X" means "substituent B with carbon number Y" is replaced by "substituent A with carbon number X". And, the carbon number Y is not the total carbon number of substituent A and substituent B. In addition, for example, "substituent B with carbon number Y replaced by substituent A" means "substituent B with carbon number Y" is replaced by "substituent A" (without carbon number restriction). And, the carbon number Y is not the total carbon number of substituent A and substituent B.

[0086] <Description of Ring and Substituent>

[0087] First, the details of the rings and substituents used in the present specification are described below.

[0088] In the present specification, examples of the “aryl ring” include an aryl ring having 6 to 30 carbon atoms, preferably an aryl ring having 6 to 16 carbon atoms, more preferably an aryl ring having 6 to 12 carbon atoms, and particularly preferably an aryl ring having 6 to 10 carbon atoms.

[0089] Specific examples of the "aryl ring" include a benzene ring as a monocyclic ring system, a biphenyl ring as a bicyclic ring system, a naphthalene ring and an indene ring as a condensed bicyclic ring system, a terphenyl ring (meta-terphenyl, o-terphenyl, p-terphenyl) as a tricyclic ring system, an acenaphthylene ring, a fluorene ring, a phenalene ring, a phenanthrene ring, and an anthracene ring as a condensed tricyclic ring system, a triphenylene ring, a pyrene ring, a naphthacene ring, Ring, as a perylene ring, pentacene ring, etc. of a condensed five-ring system. In addition, the fluorene ring, benzofluorene ring, and indene ring also include structures in which the fluorene ring, benzofluorene ring, cyclopentane ring, etc. are spiro-bonded. In addition, the fluorene ring, benzofluorene ring, and indene ring also include the case where two of the hydrogen atoms of the two methylene groups in the structure are replaced by an alkyl group such as a methyl group as described below as the first substituent to form a dimethylfluorene ring, a dimethylbenzofluorene ring, a dimethylindene ring, etc.

[0090] In the present specification, examples of the “heteroaryl ring” include a heteroaryl ring having 2 to 30 carbon atoms, preferably a heteroaryl ring having 2 to 25 carbon atoms, more preferably a heteroaryl ring having 2 to 20 carbon atoms, further preferably a heteroaryl ring having 2 to 15 carbon atoms, and particularly preferably a heteroaryl ring having 2 to 10 carbon atoms. Examples of the “heteroaryl ring” include a heterocyclic ring containing, in addition to carbon, 1 to 5 heteroatoms selected from oxygen, sulfur, nitrogen, boron, silicon, selenium, phosphorus, and tellurium as ring-constituting atoms.

[0091] Specific examples of the "heteroaryl ring" include a pyrrole ring, an oxazole ring, an isoxazole ring, a thiazole ring, an isothiazole ring, an imidazole ring, an oxadiazole ring (such as a furazan ring), a thiadiazole ring, a triazole ring, a tetrazole ring, a pyrazole ring, a pyridine ring, a pyrimidine ring, a pyridazine ring, a pyrazine ring, a triazine ring, an indole ring, an isoindole ring, a 1H-indazole ring, a benzimidazole ring, a benzoxazole ring, a benzothiazole ring, a 1H-benzotriazole ring, a quinoline ring, an isoquinoline ring, a cinnoline ring, a quinazoline ring, a quinoxaline ring, a phthalazine ring, a naphthyridine ring, a purine ring, a pteridine ring, a carbazole ring, an acridine ring, a phenoxathiol ring, a phenoxazine ring, a phenothiazine ring, a phenazine ring, a silazoanthracene ring, a phenazas iline) ring, indolizine ring, furan ring, benzofuran ring, isobenzofuran ring, dibenzofuran ring, thiophene ring, benzothiophene ring, dibenzothiophene ring, thianthrene ring, indolecarbazole ring, benzindolecarbazole ring, dibenzoindolecarbazole ring, naphthobenzofuran ring, dioxin ring, dihydroacridine ring, xanthene ring, thioxanthene ring, dibenzodioxin ring, dioxaborinaphthoanthracene ring (5,9-dioxa-13b-bora-13bH-naphtho[3,2,1-de]anthracene ring ring), silanthene ring, silanthene ring, benzoselenophene ring, dibenzoselenophene ring, azacarbazole ring, azadibenzothiophene ring, azadibenzofuran ring, azasilanthene ring, azadibenzoselenophene ring, azatriphenylene ring, imidazoimidazole ring, indoloindole ring, benzofluorocarbazole ring, benzothiophenocarbazole ring, indenocarbazole ring and selenophenecarbazole ring, spiro[fluorene-9,9'-xanthene] ring, spirobis[silanthene] ring, etc. In addition, it is preferred that two of the hydrogen atoms of the two methylene groups in the dihydroacridine ring, xanthene ring, and thioxanthene ring structure are substituted with an alkyl group such as a methyl group as the first substituent described below to form a dimethyldihydroacridine ring, a dimethylxanthene ring, a dimethylthioxanthene ring, etc. In addition, bicyclic rings such as bipyridine ring, phenylpyridine ring, and pyridylbenzene ring, and tricyclic rings such as tripyridine ring, bipyridylbenzene ring, and pyridylbiphenyl ring are also exemplified as “heteroaryl rings.” In addition, “heteroaryl rings” include pyran rings.

[0092] In this specification, a substituent is sometimes substituted by an additional substituent. For example, a specific substituent is sometimes described as "substituted or unsubstituted". This means that the specific substituent is unsubstituted or substituted by at least one additional substituent. The same meaning is sometimes referred to as "may be substituted". In this specification, there is a case where the specific substituent at this time is referred to as a "first substituent" and the additional substituent is referred to as a "second substituent".

[0093] In the present specification, the substituent group Zα includes the substituents of the substituent group Z and a substituent represented by the formula (A30) described below.

[0094] In the present specification, the substituent group Z includes:

[0095] The aryl group may be substituted by at least one group selected from the group consisting of an aryl group, a heteroaryl group, an alkyl group, a cycloalkyl group, a cyano group and a halogen group,

[0096] The heteroaryl group may be substituted by at least one group selected from the group consisting of an aryl group, a heteroaryl group, an alkyl group, a cycloalkyl group, a cyano group and a halogen group,

[0097] The diarylamino group (two aryl groups may be bonded to each other via a linker) may be substituted by at least one group selected from the group consisting of an aryl group, a heteroaryl group, an alkyl group, a cycloalkyl group, a cyano group and a halogen group,

[0098] The diheteroarylamino group (two heteroaryl groups may be bonded to each other via a linker) may be substituted by at least one group selected from the group consisting of an aryl group, a heteroaryl group, an alkyl group, a cycloalkyl group, a cyano group and a halogen group,

[0099] The arylheteroarylamino group (the aryl group and the heteroaryl group may be bonded to each other via a linker) may be substituted by at least one group selected from the group consisting of an aryl group, a heteroaryl group, an alkyl group, a cycloalkyl group, a cyano group and a halogen group,

[0100] The diarylboryl group (two aryl groups may be bonded via a single bond or a linking group) may be substituted by at least one group selected from the group consisting of an aryl group, a heteroaryl group, an alkyl group, a cycloalkyl group, a cyano group and a halogen group,

[0101] The alkyl group may be substituted by at least one group selected from the group consisting of an aryl group, a heteroaryl group, a cycloalkyl group, a cyano group and a halogen group,

[0102] The cycloalkyl group may be substituted by at least one group selected from the group consisting of an aryl group, a heteroaryl group, an alkyl group, a cycloalkyl group, a cyano group and a halogen group,

[0103] The alkoxy group may be substituted by at least one group selected from the group consisting of an aryl group, a heteroaryl group, a cycloalkyl group, a cyano group and a halogen group,

[0104] The aryloxy group may be substituted by at least one group selected from the group consisting of aryl, heteroaryl, alkyl, cycloalkyl, cyano and halogen.

[0105] Substituted silyl, cyano and halogen.

[0106] The aryl group as the second substituent in each group of the substituent group Z may be further substituted by an aryl group, a heteroaryl group, an alkyl group, a cycloalkyl group, a cyano group or a halogen. Similarly, the heteroaryl group as the second substituent may be substituted by an aryl group, a heteroaryl group, an alkyl group, a cycloalkyl group, a cyano group or a halogen.

[0107] In the present specification, when referred to as a "substituent", the type of the substituent is not particularly limited, but unless otherwise specified, any group selected from the substituent group Z may be used. For example, when a "substituted or unsubstituted" group is substituted, the group may be substituted with at least one group selected from the substituent group Z.

[0108] In the present specification, the "aryl group" is, for example, an aryl group having 6 to 30 carbon atoms, and is preferably an aryl group having 6 to 20 carbon atoms, an aryl group having 6 to 16 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an aryl group having 6 to 10 carbon atoms.

[0109] Specific examples of the "aryl group" include a monovalent group obtained by removing one hydrogen atom from the above-mentioned "aryl ring". For example, phenyl as a monocyclic ring system, biphenyl (2-biphenyl, 3-biphenyl, or 4-biphenyl) as a bicyclic ring system, naphthyl (1-naphthyl or 2-naphthyl) as a condensed bicyclic ring system, terphenyl (m-terphenyl-2'-yl, m-terphenyl-4'-yl, m-terphenyl-5'-yl, o-terphenyl-3'-yl, o-terphenyl-4'-yl, p-terphenyl-2'-yl, m-terphenyl-2-yl, m-terphenyl-3-yl, m-terphenyl-4-yl, o-terphenyl-2-yl, o-terphenyl-3-yl, o-terphenyl-4-yl, p-terphenyl-2-yl, p-terphenyl-3-yl, or p-terphenyl-4-yl) as a tricyclic ring system, acenaphthene (1-, 3-, 4-, or 5- The invention also includes the following: anthracene-(1-, 2-, 3-, 4-, or 9-) group, phenanthren-(1-, 2-, 3-, 4-, or 9-) group, a tetraphenyl group (5'-phenyl-m-terphenyl-2-yl, 5'-phenyl-m-terphenyl-3-yl, 5'-phenyl-m-terphenyl-4-yl, or m-quaterphenyl) as a tetracyclic ring system, a triphenylene-(1-, 2-, pyrene-(1-, 2-, or 4-) group, or a tetracene-(1-, 2-, or 5-) group as a condensed tetracyclic ring system, or a perylene-(1-, 2-, or 3-) group or a pentacene-(1-, 2-, 5-, or 6-) group as a condensed pentacyclic ring system, and the like. In addition, a monovalent group of spirofluorene and the like can be mentioned.

[0110] In addition, the aryl group as the second substituent also includes a structure in which the aryl group is substituted by at least one group selected from the following group: aryl groups such as phenyl (specific examples are the above-mentioned groups), alkyl groups such as methyl (specific examples are the groups described below), and cycloalkyl groups such as cyclohexyl or adamantyl (specific examples are the groups described below).

[0111] As an example, a group in which the nine positions of the fluorenyl group as the second substituent are substituted with an aryl group such as a phenyl group, an alkyl group such as a methyl group, or a cycloalkyl group such as a cyclohexyl group or an adamantyl group.

[0112] The “arylene group” is, for example, an arylene group having 6 to 30 carbon atoms, and is preferably an arylene group having 6 to 20 carbon atoms, an arylene group having 6 to 16 carbon atoms, an arylene group having 6 to 12 carbon atoms, or an arylene group having 6 to 10 carbon atoms.

[0113] Specific examples of the "arylene group" include a divalent group obtained by removing one hydrogen atom from the above-mentioned "aryl group" (monovalent group).

[0114] The “heteroaryl group” is, for example, a heteroaryl group having 2 to 30 carbon atoms, and is preferably a heteroaryl group having 2 to 25 carbon atoms, a heteroaryl group having 2 to 20 carbon atoms, a heteroaryl group having 2 to 15 carbon atoms, or a heteroaryl group having 2 to 10 carbon atoms. The “heteroaryl group” contains, in addition to carbon atoms, one or more, preferably 1 to 5 heteroatoms selected from oxygen, sulfur, nitrogen, and the like as ring-constituting atoms.

[0115] Specific examples of the "heteroaryl group" include monovalent groups obtained by removing one hydrogen from the above-mentioned "heteroaryl ring". Examples include pyrrolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, imidazolyl, oxadiazolyl, thiadiazolyl, triazolyl, tetrazolyl, pyrazolyl, pyridyl, pyrimidyl, pyridazinyl, pyrazinyl, triazinyl, indolyl, isoindolyl, 1H-indazolyl, benzimidazolyl, benzoxazolyl, benzothiazolyl, 1H-benzotriazolyl, quinolyl, isoquinolyl, cinnolinyl, quinazolinyl, quinoxalinyl, phenanthrolinyl, phthalazinyl, naphthyridinyl, purinyl, pteridinyl, carbazolyl, acridinyl, phenoxathiol, Phenoxazinyl, phenothiazinyl, phenazinyl, phenazasilinyl, indolizinyl, furanyl, benzofuranyl, isobenzofuranyl, dibenzofuranyl, naphthobenzofuranyl, thienyl, benzothienyl, isobenzothienyl, dibenzothienyl, naphthobenzothienyl, a monovalent group of a benzophosphorus oxide ring, a monovalent group of a dibenzophosphorus oxide ring, furazanyl, thianthrenyl, indolecarbazolyl, benzindolecarbazolyl, dibenzoindolecarbazolyl, imidazolinyl, or oxazolinyl. In addition, a monovalent group of spiro[fluorene-9,9'-xanthene], a monovalent group of spirobis[silicon fluorene], or a monovalent group of benzoselenophene can be mentioned.

[0116] In addition, the heteroaryl group as the second substituent also includes a structure in which the heteroaryl group is substituted by at least one group selected from the following group: aryl groups such as phenyl (specific examples are the above-mentioned groups), alkyl groups such as methyl (specific examples are the groups described below), and cycloalkyl groups such as cyclohexyl or adamantyl (specific examples are the groups described below).

[0117] As an example, the second substituent includes a group in which nine positions of the carbazolyl group are substituted with an aryl group such as a phenyl group, an alkyl group such as a methyl group, or a cycloalkyl group such as a cyclohexyl group or an adamantyl group. In addition, a group in which a nitrogen-containing heteroaryl group such as a pyridyl group, a pyrimidyl group, a triazine group, a carbazolyl group is further substituted with a phenyl group or a biphenyl group is also included in the heteroaryl group as the second substituent.

[0118] The “heteroarylene group” is, for example, a heteroarylene group having 2 to 30 carbon atoms, and is preferably a heteroarylene group having 2 to 25 carbon atoms, a heteroarylene group having 2 to 20 carbon atoms, a heteroarylene group having 2 to 15 carbon atoms, or a heteroarylene group having 2 to 10 carbon atoms. In addition, the “heteroarylene group” is, for example, a divalent group such as a heterocycle containing, in addition to carbon, 1 to 5 hetero atoms selected from oxygen, sulfur, and nitrogen as ring-constituting atoms.

[0119] Specific examples of the "heteroarylene group" include a divalent group obtained by removing one hydrogen atom from the above-mentioned "heteroaryl group" (monovalent group).

[0120] The “diarylamino group” is an amino group substituted with two aryl groups, and the description of the above-mentioned “aryl group” can be cited for the details of the aryl group.

[0121] The “diheteroarylamino group” is an amino group substituted with two heteroaryl groups, and the description of the above-mentioned “heteroaryl group” can be cited for the details of the heteroaryl group.

[0122] The “arylheteroarylamino group” is an amino group substituted by an aryl group and a heteroaryl group, and the description of the above-mentioned “aryl group” and “heteroaryl group” can be cited for the details of the aryl group and the heteroaryl group.

[0123] The two aryl groups in the diarylamino group as the first substituent may be bonded to each other through a linking group, the two heteroaryl groups in the diheteroarylamino group as the first substituent may be bonded to each other through a linking group, and the aryl group and the heteroaryl group in the arylheteroarylamino group as the first substituent may be bonded to each other through a linking group. Here, "bonded through a linking group" means that, for example, the two phenyl groups of the diphenylamino group form a bond through a linking group, as shown below. This description also applies to diheteroarylamino groups and arylheteroarylamino groups formed by aryl or heteroaryl groups.

[0124]

[0125] (*Indicates the bond position.)

[0126] Specific examples of the linking group include: >O, >NR X 、>C(-R X )2, -(CR X )=(CR X )-、>Si(-R X )2, >S, >CO, >CS, >SO, >SO2, and >Se. R X are independently alkyl, cycloalkyl, aryl or heteroaryl, and these linking groups may be substituted by alkyl, cycloalkyl, aryl or heteroaryl. X )2, -(CR X )=(CR X)-、>Si(-R X )2 Each of the two R X Can be connected by a single bond or by a group X Y bond with each other to form a ring. Y , can be listed as >O, >NR Y 、>C(-R Y )2、>Si(-R Y )2, >S, >CO, >CS, >SO, >SO2, and >Se, and R Y are independently alkyl, cycloalkyl, aryl or heteroaryl; and these substituents may also be substituted by alkyl, cycloalkyl, aryl or heteroaryl. Y >C(-R Y )2 and>Si(-R Y )2, 2 R Y No longer bonded to form a ring. In addition, as a linking group, an alkenylene group can be cited. Any hydrogen in the alkenylene group can be independently connected through R 2X Replace, and R 2X They may also be independently alkyl, cycloalkyl, substituted silyl, aryl and heteroaryl, and these substituents may also be substituted by alkyl, cycloalkyl, substituted silyl or aryl. -(CR X )=(CR X )-The two Rs in X They may bond to each other and form an aryl (benzene ring, etc.) or heteroaryl ring together with the C=C to which they are bonded. X )=(CR X )- may be an arylene group (such as 1,2-phenylene) or a heteroarylene group.

[0127] In addition, when simply described as “diarylamino”, “diheteroarylamino” or “arylheteroarylamino” in the present specification, unless otherwise specified, the explanations such as “the two aryl groups of the diarylamino group may be bonded to each other via a linking group”, “the two heteroaryl groups of the diheteroarylamino group may be bonded to each other via a linking group” and “the aryl and heteroaryl groups of the arylheteroarylamino group may be bonded to each other via a linking group” are added, respectively.

[0128] "Diarylboryl" is a boron group substituted with two aryl groups, and the details of the aryl groups can be referred to the description of "aryl" above. In addition, the two aryl groups can also be bonded by a single bond or a linker (for example, -CH=CH-, -CR=CR-, -C≡C-, >NR, >O, >S, >C(-R)2, >Si(-R)2, or >Se). Here, R of -CR=CR-, R of >NR, R of >C(-R)2, and R of >Si(-R)2 are aryl, heteroaryl, diarylamino, alkyl, alkenyl, alkynyl, cycloalkyl, alkoxy or aryloxy, and at least one hydrogen in R can be further substituted with an aryl, heteroaryl, alkyl, alkenyl, alkynyl or cycloalkyl group. In addition, two adjacent Rs are bonded to each other to form a ring, and may also form a cycloalkylene, arylene and heteroarylene groups. For details of the substituents listed here, the description of the above-mentioned "aryl", "arylene", "heteroaryl", "heteroarylene" and "diarylamino" and the description of "alkyl", "alkenyl", "alkynyl", "cycloalkyl", "cycloalkylene", "alkoxy" and "aryloxy" described below can be cited. In addition, when simply describing "diarylboryl" in this specification, unless otherwise specified, the description "two aryl groups of the diarylboryl may be bonded to each other via a single bond or a linking group" is added.

[0129] "Alkyl" can be any of straight chain and branched chain, for example: a straight chain alkyl group with 1 to 24 carbon atoms or a branched chain alkyl group with 3 to 24 carbon atoms, and preferably an alkyl group with 1 to 18 carbon atoms (branched chain alkyl groups with 3 to 18 carbon atoms), an alkyl group with 1 to 12 carbon atoms (branched chain alkyl groups with 3 to 12 carbon atoms), an alkyl group with 1 to 6 carbon atoms (branched chain alkyl groups with 3 to 6 carbon atoms), an alkyl group with 1 to 5 carbon atoms (branched chain alkyl groups with 3 to 5 carbon atoms), an alkyl group with 1 to 4 carbon atoms (branched chain alkyl groups with 3 to 4 carbon atoms), etc.

[0130] Specific examples of the “alkyl group” include methyl, ethyl, n-propyl, isopropyl, 1-ethyl-1-methylpropyl, 1,1-diethylpropyl, 1,1,2-trimethylpropyl, 1,1,2,2-tetramethylpropyl, 1-ethyl-1,2,2-trimethylpropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, 2-ethylbutyl, 1,1-dimethylbutyl, 3,3-dimethylbutyl, 1,1-diethylbutyl, 1-ethyl-1-methylbutyl, 1-propyl-1-methylbutyl, 1,1,3-trimethylbutyl, 1-ethyl-1,3-dimethylbutyl, n-pentyl, isopentyl, neopentyl, t-pentyl (t-amyl), 1-methylpentyl, 2-propylpentyl, 1,1-dimethylpentyl, 1-ethyl 1-methylpentyl, 1-propyl-1-methylpentyl, 1-butyl-1-methylpentyl, 1,1,4-trimethylpentyl, n-hexyl, 1-methylhexyl, 2-ethylhexyl, 1,1-dimethylhexyl, 1-ethyl-1-methylhexyl, 1,1,5-trimethylhexyl, 3,5,5-trimethylhexyl, n-heptyl, 1-methylheptyl, 1-hexylheptyl, 1,1-dimethylheptyl, 2,2-dimethylheptyl, 2,6-dimethyl-4-heptyl, n-octyl, tert-octyl (1,1,3,3-tetramethylbutyl), 1,1-dimethyloctyl, n-nonyl, n-decyl, 1-methyldecyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, or n-eicosyl.

[0131] "Alkylene" is a divalent group obtained by removing any hydrogen from "alkyl", for example, methylene, ethylene, propylene.

[0132] Regarding the "alkenyl group", please refer to the description of the above-mentioned "alkyl group", which is a group in which the CC single bond in the structure of the "alkyl group" is replaced by a C=C double bond, including not only one but also two or more single bonds replaced by double bonds (also called diene-group or triene-group).

[0133] The "alkenylene group" is a divalent group obtained by removing any hydrogen atom in the "alkenyl group", and examples thereof include vinylene group.

[0134] Regarding the "alkynyl group", reference may be made to the description of the "alkyl group" above, which is a group in which the CC single bond in the structure of the "alkyl group" is replaced by a C≡C triple bond, including not only one but also two or more single bonds replaced by triple bonds (also referred to as a di-alkyne group or a tri-alkyne group).

[0135] The “cycloalkyl group” is, for example, a cycloalkyl group having 3 to 24 carbon atoms, and is preferably a cycloalkyl group having 3 to 20 carbon atoms, a cycloalkyl group having 3 to 16 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, a cycloalkyl group having 5 to 10 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, a cycloalkyl group having 5 to 6 carbon atoms, or a cycloalkyl group having 5 carbon atoms.

[0136] Specific examples of "cycloalkyl" include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, or alkyl (especially methyl) substituents having 1 to 5 carbon atoms or 1 to 4 carbon atoms, bicyclo[1.1.0]butyl, bicyclo[1.1.1]pentyl, bicyclo[2.1.0]pentyl, bicyclo[2.1.1]hexyl, bicyclo[3.1.0]hexyl, bicyclo[2.2.1]heptyl (norbornyl), bicyclo[2.2.2]octyl, adamantyl, diadamantyl, decahydronaphthyl, or decahydroazulyl.

[0137] “Cycloalkylene” includes, for example, cycloalkylene having 3 to 24 carbon atoms, and preferably cycloalkylene having 3 to 20 carbon atoms, cycloalkylene having 3 to 16 carbon atoms, cycloalkylene having 3 to 14 carbon atoms, cycloalkylene having 3 to 12 carbon atoms, cycloalkylene having 5 to 10 carbon atoms, cycloalkylene having 5 to 8 carbon atoms, cycloalkylene having 5 to 6 carbon atoms, or cycloalkylene having 5 carbon atoms.

[0138] Specific examples of the "cycloalkylene group" include a structure in which one hydrogen atom is removed from the above-mentioned "cycloalkyl group" (monovalent group) to form a divalent group.

[0139] "Cycloalkenyl" is a group having a structure in which at least one pair of single bonds between two carbon atoms in the above-mentioned "cycloalkyl" is converted into a double bond (for example, a group in which -CH2-CH2- is substituted by -CH=CH-), and groups not corresponding to aryl groups can be listed. Specifically, 1-cyclohexenyl, 1-cyclopentenyl, etc. can be listed.

[0140] The "alkoxy group" is a group represented by "Alk-O-(Alk is an alkyl group)", and the description of the above-mentioned "aryl group" can be cited for the details of the alkyl group.

[0141] The "aryloxy group" is a group represented by "Ar-O-(Ar is an aryl group)", and the description of the above-mentioned "aryl group" can be cited for the details of the aryl group.

[0142] The "substituted silyl group" is, for example, a silyl group substituted with at least one of an aryl group, an alkyl group and a cycloalkyl group, and is preferably a triarylsilyl group, a trialkylsilyl group, a tricycloalkylsilyl group, a dialkylcycloalkylsilyl group or an alkyldicycloalkylsilyl group.

[0143] The “triarylsilyl group” is a silyl group substituted with three aryl groups, and the description of the above-mentioned “aryl group” can be cited for the details of the aryl groups.

[0144] Specific examples of the “triarylsilyl group” include triphenylsilyl, diphenylmononaphthylsilyl, monophenyldinaphthylsilyl, and trinaphthylsilyl.

[0145] The “trialkylsilyl group” is a silyl group substituted with three alkyl groups, and the description of the above-mentioned “alkyl group” can be cited for the details of the alkyl group.

[0146] Specific examples of “trialkylsilyl” include trimethylsilyl, triethylsilyl, tri-n-propylsilyl, triisopropylsilyl, tri-n-butylsilyl, triisobutylsilyl, tri-sec-butylsilyl, tri-tert-butylsilyl, ethyldimethylsilyl, n-propyldimethylsilyl, isopropyldimethylsilyl, n-butyldimethylsilyl, isobutyldimethylsilyl, sec-butyldimethylsilyl, tert-butyldimethylsilyl, methyldiethylsilyl, n-propyldiethylsilyl, isopropyldiethylsilyl, n-butyldiethylsilyl, sec-butyldiethylsilyl, tert-butyldiethylsilyl, methyldi-n-propylsilyl, ethyldi-n-propylsilyl, n-butyldi-n-propylsilyl, sec-butyldi-n-propylsilyl, tert-butyldi-n-propylsilyl, methyldiisopropylsilyl, ethyldiisopropylsilyl, n-butyldiisopropylsilyl, sec-butyldiisopropylsilyl, or tert-butyldiisopropylsilyl, etc.

[0147] The "tricycloalkylsilyl group" is a silyl group substituted with three cycloalkyl groups, and the description of the above-mentioned "cycloalkyl group" can be cited for the details of the cycloalkyl group.

[0148] Specific examples of the "tricycloalkylsilyl group" include tricyclopentylsilyl and tricyclohexylsilyl groups.

[0149] The “dialkylcycloalkylsilyl group” is a silyl group substituted with two alkyl groups and one cycloalkyl group, and the description of the above-mentioned “alkyl group” and “cycloalkyl group” can be cited for the details of the alkyl group and the cycloalkyl group.

[0150] The “alkyldicycloalkylsilyl group” is a silyl group substituted with one alkyl group and two cycloalkyl groups, and the description of the above-mentioned “alkyl group” and “cycloalkyl group” can be cited for the details of the alkyl group and the cycloalkyl group.

[0151] The "halogen" is fluorine, chlorine, bromine or iodine, preferably fluorine, chlorine or bromine, more preferably fluorine or chlorine, further preferably fluorine.

[0152] When substituted with cyano or halogen, it is preferred that all or part of the hydrogen atoms in the aryl ring or heteroaryl ring in the structure are substituted with cyano or halogen.

[0153] The substituent represented by formula (A30) has the following structure.

[0154]

[0155] In the formula (A30),

[0156] Ak is hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted alkenyl, substituted or unsubstituted cycloalkyl, or substituted or unsubstituted cycloalkenyl, and at least one -CH2- in the alkyl, cycloalkyl and cycloalkenyl groups may be substituted by -O- or -S-,

[0157] R Ak is a substituted or unsubstituted aryl, a substituted or unsubstituted heteroaryl, a substituted or unsubstituted alkyl, or a substituted or unsubstituted cycloalkyl, R Ak It can be bonded to Ak through a linking group or a single bond, and * is the bonding position.

[0158] In formula (A30), since Ak is the substituent and is not conjugated with the non-covalent electron pair on N, the non-covalent electron pair can be conjugated with the π electrons at the bonding site, and a greater wavelength change can be achieved compared to the case where an aromatic group or the like is present at the same position. In addition, the same is true for the influence of the multiple resonance effect, and the thermally activated delayed fluorescent (TADF) property can be improved to a greater extent.

[0159] R Ak Preferred is an aryl group which may be substituted by an alkyl group or a cycloalkyl group, a heteroaryl group which may be substituted by an alkyl group or a cycloalkyl group, an alkyl group or a cycloalkyl group, more preferably an aryl group which may be substituted by an alkyl group, a heteroaryl group, an alkyl group or a cycloalkyl group, further preferably an aryl group which may be substituted by an alkyl group, and particularly preferably a phenyl group which may be substituted by a methyl group.

[0160] In formula (A30), Ak is preferably an alkyl group having 1 to 6 carbon atoms or a cycloalkyl group having 3 to 14 carbon atoms, preferably an alkyl group having 1 to 4 carbon atoms or a cycloalkyl group having 3 to 8 carbon atoms, more preferably an alkyl group having 1 to 4 carbon atoms, and further preferably a methyl group.

[0161] R Ak It may be the same as or different from Ak, but is preferably different.

[0162] R AkIt can be bonded to Ak through a linking group or a single bond. As the linking group in this case, >O, >S or >Si(-R)2 can be listed. R of >Si(-R)2 is hydrogen, an aryl group having 6 to 12 carbon atoms, an alkyl group having 1 to 6 carbon atoms or a cycloalkyl group having 3 to 14 carbon atoms. Ak Examples of the structure bonded to Ak via a linking group or a single bond include the following.

[0163]

[0164] In the above formulas, * represents the bonding position.

[0165] <When two groups bonded to the same atom are bonded to each other>

[0166] In the present specification, when two groups bonded to the same atom can bond to each other to form a ring, they can be bonded by a single bond or a linking group (all of which are collectively referred to as a bonding group). Examples of the linking group include -CH2-CH2-, -CHR-CHR-, -CR2-CR2-, -CH=CH-, -CR=CR-, -C≡C-, -N(-R)-, -O-, -S-, -C(-R)2-, -Si(-R)2- or -Se-, and examples of the following structures include. In addition, the R of -CHR-CHR-, the R of -CR2-CR2-, the R of -CR=CR-, the R of -N(-R)-, the R of -C(-R)2-, and the R of -Si(-R)2- can be independently hydrogen, aryl substituted by alkyl or cycloalkyl, heteroaryl substituted by alkyl or cycloalkyl, alkyl substituted by cycloalkyl, alkenyl substituted by alkyl or cycloalkyl, alkynyl substituted by alkyl or cycloalkyl, or cycloalkyl substituted by alkyl or cycloalkyl. In addition, two adjacent Rs can be bonded to form a ring, forming a cycloalkylene, arylene, or heteroarylene.

[0167]

[0168] As the bonding group, a single bond, -CR=CR-, -N(-R)-, -O-, -S-, -C(-R)2-, -Si(-R)2-, and -Se- are preferred as the bonding group, and a single bond, -CR=CR-, -N(R)-, -O-, -S-, and -C(-R)2- are more preferred as the bonding group, a single bond, -CR=CR-, -N(R)-, -O-, -S-, and -C(-R)2- are further preferred as the bonding group, and a single bond, -CR=CR-, -N(R)-, -O-, and -S- are most preferred.

[0169] The position where the two Rs are bonded via a bonding group is not particularly limited as long as it is a bondable position, but it is preferably bonded at the most adjacent position. For example, when the two groups are phenyl groups, it is preferred that they are bonded at the ortho position (the second position) based on the bonding position (the first position) of "C" or "Si" in the phenyl group (refer to the structural formula).

[0170] <Stereoisomerism, etc.>

[0171] The polycyclic aromatic compound of the present invention may exist as enantiomers or diastereomers depending on the type of substituents, but any single form of any stereoisomer, any mixture of stereoisomers, racemates, etc. are included in the scope of the present invention regardless of the described structural formula.

[0172] 1. Polycyclic aromatic compounds

[0173] <Description of the overall structure of the compound>

[0174] It has been found that polycyclic aromatic compounds that connect aromatic rings to heteroelements such as boron, nitrogen, oxygen, and sulfur have a large highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) gap (band gap Eg in the film). This is because the six-membered ring containing heteroelements has low aromaticity, which inhibits the reduction of the HOMO-LUMO gap caused by the expansion of the conjugated system. In addition, it has been found that the HOMO-LUMO gap can be arbitrarily changed according to the type of heteroelement and the connection method. It is believed that this is because the energy of HOMO and LUMO can be arbitrarily moved according to the spatial diffusion and energy of the empty orbital or lone pair of electrons of the heteroelement.

[0175] In these polycyclic aromatic compounds, due to the electronic disturbance of heteroelements, the excited state singly occupied molecular orbital (SOMO) 1 and SOMO 2 are localized on each atom, and the half width of the fluorescence emission peak is narrow. When used as a dopant for an organic EL element, high color purity light emission can be obtained. For the same reason, ΔE S1T1 It becomes smaller, exhibits thermally activated delayed fluorescence, and can obtain high efficiency when used as an emission dopant of an organic EL element.

[0176] Furthermore, by introducing a substituent, the energy of HOMO and LUMO can be arbitrarily moved, so that the ionization potential and electron affinity can be optimized according to the surrounding materials.

[0177] The polycyclic aromatic compound of the present invention corresponds to the polycyclic aromatic compound. The polycyclic aromatic compound of the present invention has a structure including one or more structural units represented by formula (1), and includes a structural unit represented by formula (E) at a specific position. ABC ) and a group represented by the formula (1Ar) or the formula (2Ar) as J (hereinafter sometimes referred to as "a polycyclic aromatic compound including a structural unit represented by the formula (1)").

[0178]

[0179] In the present invention, the polycyclic aromatic compound including the structural unit represented by the formula (1) includes the polycyclic aromatic compound represented by the chemical formula (E ABC ) as a substituent of the aryl ring or heteroaryl ring in the A ring, the B ring or the C ring, and at the same time including the group represented by the formula (1Ar), it was found that the organic EL element using this compound has higher efficiency and longer life. It is believed that this is because the organic EL element represented by the formula (E ABC ) in the structure represented by (1Ar) and (2Ar), the P ring and the Q ring are pushed to the upper space of the main skeleton plane composed of the A ring, the B ring and the C ring, and cover at least a portion of the plane, thereby suppressing the interaction with the adjacent molecules. A similar effect is believed to be obtained by the E ring of the structure represented by formula (1Ar) and formula (2Ar) covering at least a portion of the plane. In particular, in TADF Assisting Fluorescence (TAF) elements or phosphor-sensitized fluorescent (PSF) elements, it is believed that the emitting dopant is in the lowest excited triplet state (T1 state) due to Dexter-type energy transfer, which becomes the cause of reduced efficiency and shortened life. However, if the molecules are not in contact, Dexter-type energy transfer will not occur, so the interaction between the molecules can be suppressed, thereby avoiding the T1 state.

[0180] However, the present invention is not particularly limited to these principles.

[0181] The details of the symbols of each structure will be described below.

[0182] <Description of Ring Structure in Compound>

[0183] In formula (1), "A", "B", and "C" in the circle are symbols representing the ring structure represented by each circle. The structure represented by formula (1) has a structure in which the A ring, the B ring, and the C ring, that is, at least three aromatic rings, are connected by boron and nitrogen to further form a ring structure. The formed ring structure is a condensed ring structure formed by at least five rings.

[0184] The A ring, the B ring and the C ring are each independently a substituted or unsubstituted aryl ring, or a substituted or unsubstituted heteroaryl ring. However, at least one selected from the group consisting of the A ring, the B ring and the C ring has at least the formula (E ABC ) as a substituent or an aromatic ring having at least ABC ) as a substituent.

[0185] A ring forms a trivalent group with a bond at three consecutive atoms (preferably carbon) on the ring of the aryl ring or heteroaryl ring in its structure. Among these three bonds, A ring is bonded to two N (nitrogen) and B (boron). In A ring, the ring with the atom having the bond as the ring-constituting atom is preferably a five-membered ring or a six-membered ring, and more preferably a six-membered ring. This ring can be fused with other rings. As examples of six-membered rings, benzene rings, pyridine rings, pyrazine rings, pyrimidine rings, etc. can be listed. As examples of six-membered rings condensed with another ring, naphthalene rings, quinoline rings, dibenzofuran rings, dibenzothiophene rings, carbazole rings, etc. can be listed. As examples of five-membered rings, furan rings, thiophene rings, pyrrole rings, thiazole rings, etc. can be listed. As examples of five-membered rings condensed with another ring, benzofuran rings, benzothiophene rings, indole rings can be listed. In addition, as condensed rings, indene rings can also be listed.

[0186] The aryl ring in ring A may be selected from the group consisting of a benzene ring, a biphenyl ring, an indene ring, a naphthalene ring, a fluorene ring, an anthracene ring and a phenanthrene ring, and the heteroaryl ring may be selected from the group consisting of a benzofuran ring, a benzothiophene ring, an indole ring, a dibenzofuran ring, a dibenzothiophene ring, a carbazole ring, a naphthofuran ring, a naphthothiophene ring, a benzoindole ring, a benzoselenophene ring, a dibenzoselenophene ring, a silanthene ring and a silanthene ring. The aryl ring or heteroaryl ring in ring A is preferably a benzene ring.

[0187] Both the B ring and the C ring form a divalent group with a bond at two atoms (preferably carbon) adjacent to each other on the ring of the aryl ring or heteroaryl ring in the structure. The B ring is bonded to N (nitrogen) and B (boron) through the two bonds, and the C ring is bonded to N (nitrogen) and B (boron) through the two bonds. The ring with the atoms having the two bonds as the ring-constituting atoms in each of the B ring and the C ring is preferably a five-membered ring or a six-membered ring, and more preferably a six-membered ring. This ring can be fused with other rings. As examples of six-membered rings, benzene rings, pyridine rings, pyrazine rings, pyrimidine rings, etc. can be listed. As examples of six-membered rings condensed with another ring, naphthalene rings, quinoline rings, benzofuran rings, benzothiophene rings, indole rings, benzoselenophene rings, dibenzofuran rings, dibenzothiophene rings, carbazole rings, dibenzoselenophene rings, etc. can be listed. Examples of five-membered rings include furan rings, thiophene rings, pyrrole rings, thiazole rings, selenophene rings, etc. Examples of five-membered rings condensed with another ring include benzofuran rings, benzothiophene rings, indole rings, benzoselenophene rings, etc. In addition, indene rings may also be included as condensed rings.

[0188] The aryl ring in the B ring and the C ring may be selected from the group consisting of a benzene ring, a biphenyl ring, an indene ring, a naphthalene ring, a fluorene ring, an anthracene ring and a phenanthrene ring, and the heteroaryl ring may be selected from the group consisting of a benzofuran ring, a benzothiophene ring, an indole ring, a dibenzofuran ring, a dibenzothiophene ring, a carbazole ring, a naphthofuran ring, a naphthothiophene ring, a benzoindole ring, a benzoselenophene ring, a dibenzoselenophene ring, a silindene ring and a silindene ring. The aryl ring or heteroaryl ring in the B ring and the C ring is preferably a benzene ring, a benzofuran ring, a benzothiophene ring, an indene ring or a benzoselenophene ring, more preferably a benzene ring, a benzofuran ring, an indene ring or a benzothiophene ring, and further preferably a benzene ring.

[0189] In addition, as will be described later, for the polycyclic aromatic compound of the present invention having a structure including two or more structural units bonded to share a ring, the A ring, the B ring or the C ring may have four or five bonding bonds.

[0190] In the substituted or unsubstituted aryl ring or substituted or unsubstituted heteroaryl ring in Ring A, Ring B and Ring C, the substituent as "substituted or unsubstituted (substituted or unsubstituted)" (represented by the formula (E ABC) may be at least one substituent selected from the substituent group Zα. In addition, the substituent may be a substituted or unsubstituted diarylphosphonic acid such as diphenylphosphonic acid. When a plurality of substituents are present, the plurality of substituents may be the same as or different from each other. As the substituent, preferably a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, or a substituted or unsubstituted diarylamino group, more preferably a tert-butyl group, a substituted or unsubstituted diphenylamino group, or a substituted or unsubstituted carbazolyl group. In addition, as preferred substituents, reference may be made to the description in <Preferred Substituents> described below.

[0191] <Formula (E ABC )>

[0192] The polycyclic aromatic compound of the present invention comprises at least one compound represented by the formula (E ABC ) as a substituent for the aryl ring or heteroaryl ring in the A ring, the B ring or the C ring.

[0193]

[0194] Formula (E ABC ), * represents the bonding position to the aryl ring or heteroaryl ring.

[0195] Formula (E ABC ), "Q" and "P" in the circles are symbols indicating the ring structures represented by the circles.

[0196] Formula (E ABC ), the Q ring and the P ring form a divalent group having bonding bonds at two adjacent atoms (preferably carbon) on the aryl ring or heteroaryl ring in each structure. They are bonded to the carbon adjacent to the nitrogen through two bonding bonds.

[0197] In the substituted or unsubstituted aryl ring or substituted or unsubstituted heteroaryl ring in the Q ring and the P ring, as a substituent when it is called "substituted or unsubstituted (substituted or unsubstituted)", at least one substituent selected from the substituent group Zα is included. The ring having the element having the two bonding bonds as the ring constituent element is preferably a five-membered ring or a six-membered ring, and more preferably a six-membered ring. This ring can be fused with other rings. Examples of six-membered rings include benzene rings, pyridine rings, pyrazine rings, pyrimidine rings, etc. Examples of six-membered rings condensed with another ring include naphthalene rings, quinoline rings, benzofuran rings, benzothiophene rings, indole rings, benzoselenophene rings, dibenzofuran rings, dibenzothiophene rings, carbazole rings, dibenzoselenophene rings, silanol rings, etc. Examples of five-membered rings include furan rings, thiophene rings, pyrrole rings, thiazole rings, and selenophene rings. Examples of the condensation of a five-membered ring with another ring include a benzofuran ring, a benzothiophene ring, an indole ring, a benzoselenophene ring, and a silindene ring.

[0198] As the Q ring and the P ring, it is preferred that they are independently substituted or unsubstituted benzene rings, substituted or unsubstituted dibenzofuran rings, substituted or unsubstituted dibenzothiophene rings, substituted or unsubstituted dibenzoselenophene rings, substituted or unsubstituted silylene rings, or substituted or unsubstituted N-phenylcarbazole rings, more preferably unsubstituted benzene rings, unsubstituted dibenzofuran rings, unsubstituted dibenzothiophene rings, unsubstituted dibenzoselenophene rings, unsubstituted diphenylsilylene rings, or unsubstituted N-phenylcarbazole rings, and further preferably unsubstituted benzene rings. At least one of the Q ring and the P ring is preferably a substituted or unsubstituted benzene ring, more preferably an unsubstituted benzene ring. The Q ring and the P ring are preferably both unsubstituted benzene rings.

[0199] As the formula (E ABC Preferred examples of the group represented by the formula (E ABC -1), formula (E ABC -2), formula (E ABC -3), formula (E ABC -4) or formula (E ABC -5) represents the basis.

[0200]

[0201] In the formula (E ABC -2) to formula (E ABC -5) In X For -C(-R ZX )=or -N=-, and preferably all are -C(-R ZX )=.

[0202] R ZX Each of R is independently hydrogen or a substituent. ZX When it is a substituent, the substituent may be at least one substituent selected from the substituent group Zα, preferably halogen, cyano, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl, more preferably unsubstituted alkyl. ZX All hydrogen.

[0203] Y 1 >NR NY 、>C(-R CY )2、>O、>Si(-R IY 2. PR PY 、>P(=O)R POY ,>S,>SO,>SO2 or>Se,

[0204] RNY , R CY , R IY , R PY and R POY are each independently hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl, and both R CY Can bond to each other to form a ring, two R IY They may bond to each other to form a ring. NY It is preferably a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, and more preferably an unsubstituted phenyl group. CY and R IY Preferably, they are each independently an aryl group having 6 to 18 carbon atoms or an alkyl group having 1 to 18 carbon atoms, and more preferably, an unsubstituted phenyl group or a methyl group.

[0205] As Y 1 , preferably >NR NY , >O, or >S.

[0206] Z E are independently -C(-R ZE )=or-N=,R ZE Each of R is independently hydrogen or a substituent. ZE When it is a substituent, the substituent may be at least one substituent selected from the substituent group Zα, preferably halogen, cyano, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl, more preferably unsubstituted alkyl. ZE All hydrogen.

[0207] Z for -N= E In the formula (E ABC -1) to formula (E ABC -5) preferably has 0 to 2, more preferably 0 to 1, and even more preferably 0. ABC -1) to formula (E ABC -5), preferably Z E All are -C(-R ZE )=.

[0208] In the formula (E ABC -1) to formula (E ABC -5) is preferably the formula (E ABC -1), formula (E ABC -2), formula (E ABC -3) and formula (E ABC -5), more preferably the formula (E ABC -1), formula (EABC -2) and formula (E ABC -5).

[0209] As an example of formula (E ABC -1) to formula (E ABC -5), the structures represented by any of the following can be cited.

[0210]

[0211]

[0212] In formula (1), the number of the groups represented by formula (E ABC ) is preferably 1 to 3, more preferably 1 to 2. When the polycyclic aromatic compound including the structural unit represented by formula (1) contains a plurality of groups represented by formula (E ABC ), the plurality of groups represented by formula (E ABC ) may be the same as or different from each other. From the viewpoint of easy synthesis, it is preferable that the plurality of groups represented by formula (E ABC ) are the same as each other.

[0213] The substitution position of the group represented by formula (E ABC ) is not particularly limited. However, when the aryl ring to which the group represented by formula (E ABC ) is bonded is a benzene ring, it is preferable that the group represented by formula (E ABC ) is substituted at the para-position of boron (B).

[0214] In addition, the group represented by formula (E ABC ) may be included in any of the A ring, the B ring, and the C ring, but is preferably included in at least one of the B ring and the C ring. When at least one of the B ring and the C ring, particularly both of them, are benzene rings in which the group represented by formula (E ABC ) is substituted at the para-position of boron (B), the interaction with adjacent molecules can be further suppressed.

[0215] <Explanation of J

[0216] In formula (1), J is each independently a group represented by formula (1Ar) or formula (2Ar), and at least one J is a group represented by formula (1Ar). J may each independently be a group represented by formula (1Ar).

[0217]

[0218] In formula (1Ar) and formula (2Ar), ring D and ring E are substituted or unsubstituted aryl rings, or substituted or unsubstituted heteroaryl rings. In formula (1Ar), G is the same or different and is hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted arylthio, substituted or unsubstituted heteroarylthio, substituted or unsubstituted aryloxy, substituted or unsubstituted heteroaryloxy, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl. , or a substituted or unsubstituted silyl group, at least one G is a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, a substituted or unsubstituted arylthio group, a substituted or unsubstituted heteroarylthio group, a substituted or unsubstituted aryloxy group, a substituted or unsubstituted heteroaryloxy group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, or a substituted or unsubstituted silyl group, and the aryl ring or heteroaryl ring in G may be bonded to the D ring or the E ring through a single bond or a linking group. # indicates the bonding position to N (nitrogen).

[0219] The polycyclic aromatic compound of the present invention has a group represented by formula (1Ar), and as described above, the organic EL element using the group can achieve higher efficiency and longer life. In addition, compared with similar compounds without the group, the polycyclic aromatic compound of the present invention having a group represented by formula (1Ar) has a low sublimation temperature. The reduction in sublimation temperature can be purified at a lower temperature in the sublimation purification, which is almost indispensable as a purification method for materials for organic devices such as organic EL elements requiring high purity, so it means that thermal decomposition of materials can be avoided. In addition, this is also true for a powerful method for making organic devices such as organic EL elements, namely the vacuum evaporation process, because the process can be implemented at a lower temperature, which means that thermal decomposition of materials can be avoided, and finally a high-performance organic device can be obtained. Although not bound by a specific theory, it is believed that the reduction in sublimation temperature is due to the group represented by formula (1Ar) having a bulky group in the E ring and G, thereby making the overall volume of the molecule higher.

[0220] In addition, by having a group represented by formula (1Ar), the polycyclic aromatic compound of the present invention has a shorter wavelength of light emission, improved light emission efficiency, and longer device life than a compound not having a group represented by formula (1Ar). Although not bound by a specific theory, it is believed that this is because the skeleton participating in light emission is spatially protected by the group represented by formula (1Ar), thereby reducing the interaction with the surrounding molecules and making it difficult for the decomposition reaction to occur.

[0221] In formula (1Ar) and formula (2Ar), "D" and "E" in the circle are symbols representing the ring structure represented by the circle, and the D ring and the E ring are substituted or unsubstituted aryl rings, or substituted or unsubstituted heteroaryl rings. The D ring and the E ring form a divalent group having a bond at two adjacent atoms (preferably carbon) on the aryl ring or heteroaryl ring in the structure, and are bonded to N (nitrogen) and G through two bonds. When the aryl ring or heteroaryl ring in G is bonded to the D ring or the E ring through a single bond or a linking group, the D ring or the E ring forms a trivalent group having a bond at three elements (preferably carbon) on the aryl ring or heteroaryl ring in the structure. Preferably, the three elements are adjacent to each other.

[0222] In the substituted or unsubstituted aryl ring or substituted or unsubstituted heteroaryl ring in the D ring and the E ring, as a substituent when referred to as "substituted or unsubstituted (substituted or unsubstituted)", at least one substituent selected from the substituent group Zα can be mentioned, and an unsubstituted alkyl group is preferred.

[0223] In the D ring and the E ring, the aryl ring may be selected from the group consisting of a benzene ring, a biphenyl ring, an indene ring, a naphthalene ring, a fluorene ring, an anthracene ring and a phenanthrene ring, and the heteroaryl ring may be selected from the group consisting of a benzofuran ring, a benzothiophene ring, an indole ring, a dibenzofuran ring, a dibenzothiophene ring, a carbazole ring, a naphthofuran ring, a naphthothiophene ring, a benzoindole ring, a benzoselenophene ring, a dibenzoselenophene ring, a silanthene ring and a silanthene ring. The D ring and the E ring are preferably a substituted or unsubstituted benzene ring, a substituted or unsubstituted benzothiophene ring, a substituted or unsubstituted benzofuran ring, or a substituted or unsubstituted indole ring, and more preferably a substituted or unsubstituted benzene ring.

[0224] In formula (1Ar), as the linking group when the aryl ring or heteroaryl ring in G is bonded to the D ring or the E ring via a single bond or a linking group, -CH2-CH2-, -CHR-CHR-, -CR2-CR2-, -CH=CH-, -CR=CR-, -C≡C-, -N(-R)-, -O-, -S-, -C(-R)2-, -C(=O)-, -Si(-R)2- or -Se-, etc. Among them, -CH=CH-, -CR L =CR L -、-N(-R L )-, -O-, -S- and -C(-R L )2-, more preferably -CH=CH-, -CR L =CR L -、-N(-R L )-, -O- and -S-, more preferably -CR L =CR L -、-N(-R L)-, -O- and -S-. L are each independently hydrogen, aryl which may be substituted by alkyl or cycloalkyl, heteroaryl which may be substituted by alkyl or cycloalkyl, alkyl which may be substituted by alkyl or cycloalkyl, alkenyl which may be substituted by alkyl or cycloalkyl, alkynyl which may be substituted by alkyl or cycloalkyl, or cycloalkyl which may be substituted by alkyl or cycloalkyl. L In addition, two adjacent R L They may be bonded to each other to form a cycloalkylene ring, an arylene ring, or a heteroarylene ring. These rings may also be substituted by an alkyl group or a cycloalkyl group.

[0225] A preferred example of the group represented by the formula (1Ar) is a group represented by the formula (1Ar-1). A preferred example of the group represented by the formula (2Ar) is a group represented by the formula (2Ar-1).

[0226]

[0227] In formula (1Ar-1) and formula (2Ar-1), R e are each independently hydrogen or a substituent, and are preferably substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted aryl, or substituted or unsubstituted silyl, and more preferably substituted or unsubstituted alkyl. e R as a substituent e Preferably, it is 0 to 2, more preferably 0 to 1. For example, R e All are hydrogen, or preferably one or two R e is unsubstituted alkyl or unsubstituted cycloalkyl and other R e For hydrogen.

[0228] In formula (1Ar-1) and formula (2Ar-1), R d Each of the two R is independently hydrogen or a substituent, and is preferably hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, or substituted or unsubstituted aryl, and more preferably hydrogen or unsubstituted alkyl. d R as a substituent d Preferably, it is 0 to 2, and more preferably, it is 0 to 1. dd It is hydrogen or a substituent, and is preferably hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted aryl, or substituted or unsubstituted heteroaryl, more preferably hydrogen, substituted or unsubstituted alkyl, or substituted or unsubstituted aryl, and further preferably hydrogen or unsubstituted phenyl.

[0229] In formula (1Ar-1), G's are the same or different and are hydrogen, unsubstituted alkyl, haloalkyl, unsubstituted cycloalkyl, unsubstituted aryl, or unsubstituted heteroaryl, and at least one G is an unsubstituted alkyl, haloalkyl, unsubstituted cycloalkyl, unsubstituted aryl, or unsubstituted heteroaryl.

[0230] As an example of the formula (1Ar-1), the structure represented by any of the following can be mentioned.

[0231]

[0232]

[0233]

[0234]

[0235]

[0236]

[0237]

[0238]

[0239] The plurality of groups represented by the formula (1Ar) in the polycyclic aromatic compound including the structural unit represented by the formula (1) may be the same or different from each other. From the viewpoint of ease of synthesis, the plurality of groups represented by the formula (1Ar) are preferably the same as each other.

[0240] <Structures including one or more structural units>

[0241] The polycyclic aromatic compound of the present invention is a polycyclic aromatic compound having a structure including one or two or more structural units represented by Chemical Formula 1.

[0242] The polycyclic aromatic compound having a structure including one of the structural units is a polycyclic aromatic compound represented by the formula explained above as the structural unit represented by formula (1).

[0243] A polycyclic aromatic compound having a structure including two or more structural units represented by formula (1) is a compound corresponding to a polymer of a polycyclic aromatic compound represented by the formula described above as a structural unit represented by formula (1). The polymer is preferably a dimer to a hexamer, and more preferably a dimer to a trimer. As long as the polymer has a plurality of the unit structures in one compound, it can also be a form in which a plurality of unit structures share any ring (A ring, B ring or C ring) contained in the structural unit, and can also be a form in which a plurality of rings (A ring, B ring or C ring) contained in the unit structure are bonded by condensation. In addition, it can also be a form in which a plurality of unit structures share any ring (A ring, B ring or C ring) contained in the structural unit and X bonded thereto. The structural unit can be a form bonded by a plurality of single bonds, alkylene groups with a carbon number of 1 to 3, phenylene groups, naphthylene groups and other connecting groups. Among them, a form in which a ring is bonded is preferably shared. In the polycyclic aromatic compound having a structure including two or more structural units represented by the formula (1), the two or more structural units may be the same as or different from each other.

[0244] Each structural unit may also include a structure having the formula (E ABC ) is an aryl ring or heteroaryl ring as a substituent, but the polycyclic aromatic compound as a whole may contain at least one.

[0245] <Formula (1X1)>

[0246] Preferred examples of the polycyclic aromatic compound having a structure including one or two or more structural units represented by the formula (1) include polycyclic aromatic compounds represented by the formula (1X1).

[0247]

[0248] In the formula (1X1), J is the same as J in the formula (1), and the preferred range is also the same. a is hydrogen or unsubstituted alkyl, and is preferably hydrogen, methyl or tert-butyl. b The same or different, and at least one R b Formula (E ABC ). b Not the formula (E ABC ) may be hydrogen or a substituent. Examples of the substituent include substituted or unsubstituted diarylamino groups, and substituted or unsubstituted diarylamino groups are preferably diphenylamino groups, biphenylphenylamino groups, and the like. R b All of them can be of formula (E ABC ), and may also be independently of the formula (E ABC -1), formula (E ABC -2), formula (EABC -3), formula (E ABC -4) or formula (E ABC -5).

[0249] <Preferred Substituents>

[0250] In the polycyclic aromatic compound used as an emitting dopant (in addition to the compound used as a dopant), as a substituent containing an "alkyl", a tertiary alkyl represented by the following formula (tR) is a substituent at the aryl ring or heteroaryl ring in the A ring, the B ring and the C ring, and is one of the particularly preferred substituents. Since this bulky substituent increases the distance between molecules, the photoluminescence quantum yield (PLQY) is improved. In addition, it is preferred that other substituents are substituted by a tertiary alkyl represented by formula (tR) as a second substituent. Specifically, a diarylamino substituted by a tertiary alkyl represented by formula (tR), a carbazolyl substituted by a tertiary alkyl represented by formula (tR) (preferably an N-carbazolyl) or a benzocarbazolyl substituted by a tertiary alkyl represented by formula (tR) (preferably an N-benzocarbazolyl). Examples of substitution forms of the group of formula (tR) at the diarylamino group, carbazolyl group and benzocarbazolyl group include a case where a part or all of the hydrogen atoms of the aryl ring or benzene ring in these groups are substituted with the group of formula (tR).

[0251]

[0252] In the formula (tR), R a , R b and R c Each independently represents an alkyl group having 1 to 24 carbon atoms, and any -CH2- in the alkyl group may be substituted by -O-. The group represented by the formula (tR) has * as a bonding position.

[0253] As R a , R b and R c The "alkyl group having 1 to 24 carbon atoms" may be any of a straight chain and a branched chain, and examples thereof include a straight chain alkyl group having 1 to 24 carbon atoms or a branched chain alkyl group having 3 to 24 carbon atoms, an alkyl group having 1 to 18 carbon atoms (branched chain alkyl group having 3 to 18 carbon atoms), an alkyl group having 1 to 12 carbon atoms (branched chain alkyl group having 3 to 12 carbon atoms), an alkyl group having 1 to 6 carbon atoms (branched chain alkyl group having 3 to 6 carbon atoms), and an alkyl group having 1 to 4 carbon atoms (branched chain alkyl group having 3 to 4 carbon atoms).

[0254] R in the formula (tR) of formula (1) a , R b and R cThe sum of the carbon numbers of is preferably 3 to 20, particularly preferably 3 to 10.

[0255] As R a , R b and R c Specific examples of the alkyl group include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, n-hexyl, 1-methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl, 2-ethylbutyl, n-heptyl, 1-methylhexyl, n-octyl, tert-octyl, 1-methylheptyl, 2-ethylhexyl, 2-propylpentyl, n-nonyl, 2,2-dimethylheptyl, 2,6-dimethyl-4-heptyl, 3,5,5-trimethylhexyl, n-decyl, n-undecyl, 1-methyldecyl, n-dodecyl, n-tridecyl, 1-hexylheptyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, and n-eicosyl.

[0256] Examples of the group represented by the formula (tR) include tert-butyl, tert-amyl, 1-ethyl-1-methylpropyl, 1,1-diethylpropyl, 1,1-dimethylbutyl, 1-ethyl-1-methylbutyl, 1,1,3,3-tetramethylbutyl, 1,1,4-trimethylpentyl, 1,1,2-trimethylpropyl, 1,1-dimethyloctyl, 1,1-dimethylpentyl, 1,1-dimethylheptyl, 1,1,5-trimethylhexyl, 1-ethyl-1-methylhexyl, 1-ethyl-1,3-dimethylbutyl, 1,1,2,2-tetramethylpropyl, 1-butyl-1-methylpentyl, 1,1-diethylbutyl, 1-ethyl-1-methylpentyl, 1,1,3-trimethylbutyl, 1-propyl-1-methylpentyl, 1,1,2-trimethylpropyl, 1-ethyl-1,2,2-trimethylpropyl, 1-propyl-1-methylbutyl, 1,1-dimethylhexyl, etc. Among them, tert-butyl and tert-pentyl are preferred.

[0257] As the substituent, a substituent represented by the formula (A30) is also preferred.

[0258] The emission wavelength can be adjusted by the structural steric hindrance, electron donation and electron attraction of the substituent of the compound used as a dopant (auxiliary dopant or emission dopant). Preferably, it is a group represented by the following structural formula, and more preferably, it is methyl, tert-butyl, tert-amyl, tert-octyl, neopentyl, adamantyl, dimethyladamantyl, phenyl, o-tolyl, p-tolyl, 2,4-xylyl (xylyl), 2,5-xylyl, 2,6-xylyl, 2,4,6-trimethylphenyl, diphenylamino, di-p-tolylamino, bis(p-(tert-butyl)phenyl)amino, carbazolyl, 3,6-dimethylcarbazolyl, 3,6 -di-tert-butylcarbazolyl and phenoxy, more preferably methyl, tert-butyl, tert-amyl, tert-octyl, neopentyl, adamantyl, phenyl, o-tolyl, 2,6-xylyl, 2,4,6-trisyl, diphenylamino, di-p-tolylamino, bis(p-(tert-butyl)phenyl)amino, carbazolyl, 3,6-dimethylcarbazolyl and 3,6-di-tert-butylcarbazolyl and tribenzoazepinyl. From the viewpoint of ease of synthesis, the steric hindrance is large and is preferably used for selective synthesis, and specifically, tert-butyl, tert-amyl, tert-octyl, adamantyl, dimethyladamantyl, o-tolyl, p-tolyl, 2,4-xylyl, 2,5-xylyl, 2,6-xylyl, 2,4,6-trisyl, di-p-tolylamino, bis(p-(tert-butyl)phenyl)amino, 3,6-dimethylcarbazolyl and 3,6-di-tert-butylcarbazolyl are preferably used.

[0259] In the following structural formulas, * indicates a bonding position.

[0260]

[0261]

[0262]

[0263]

[0264]

[0265]

[0266]

[0267]

[0268]

[0269]

[0270]

[0271]

[0272] The polycyclic aromatic compound including the structural unit represented by formula (1) is preferably a structure containing at least one tertiary alkyl group (tert-butyl or tert-amyl, etc.), neopentyl or adamantyl represented by the above formula (tR), and preferably a structure containing a tertiary alkyl group (tert-butyl or tert-amyl, etc.) represented by formula (tR). The reason is that this bulky substituent increases the distance between molecules, thereby improving the luminescence quantum yield (PLQY). In addition, as a substituent, a diarylamino group is also preferred. Furthermore, it is also preferred to be a diarylamino group substituted with a base of formula (tR), a carbazolyl group substituted with a base of formula (tR) (preferably N-carbazolyl) or a benzocarbazolyl group substituted with a base of formula (tR) (preferably N-benzocarbazolyl). As a substitution form of the base of formula (tR) in diarylamino, carbazolyl and benzocarbazolyl, examples of a part or all of the hydrogens of the aryl ring or benzene ring in the base being substituted with a base of formula (tR) can be cited.

[0273] In particular, in the substituted or unsubstituted aryl ring or substituted or unsubstituted heteroaryl ring in the A ring, B ring and C ring of the polycyclic aromatic compound including the structural unit represented by formula (1), the substituent when "substituted or unsubstituted (substituted or unsubstituted)" includes a substituted or unsubstituted N-carbazolyl group. When a compound having an N-carbazolyl group as a substituent is used as a dopant in the light-emitting layer, it is found that an organic EL element with a lower driving voltage and a longer life is obtained. It is believed that due to the presence of an N-carbazolyl group as a substituent, the HOMO of the compound becomes deeper, the hole capture property is reduced, and the driving voltage is reduced. In addition, it is believed that carrier recombination is difficult to occur on the dopant, and the dopant is difficult to reach the T1 state, thereby achieving a long life. Here, when the N-carbazolyl group has a substituent, the substituent is preferably selected from the group consisting of a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, a substituted or unsubstituted alkyl group, and a substituted or unsubstituted cycloalkyl group. As the substituted or unsubstituted N-carbazolyl group, an unsubstituted N-carbazolyl group or a 3,6-di(tert-butyl)N-carbazolyl group is particularly preferred.

[0274] In the structure including the structural unit represented by formula (1), a substituent of the aryl ring or heteroaryl ring may be a substituent represented by the following formula (A20).

[0275]

[0276] The substituent represented by formula (A20) is bonded to two adjacent atoms on the aryl ring or heteroaryl ring at two * positions, respectively. In formula (A20), L is >NR, >O, >Si(-R)2 or >S, R of the >NR is a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted cycloalkyl group, R of the >Si(-R)2 is hydrogen, a substitutable aryl group, a substitutable alkyl group, or a substitutable cycloalkyl group, and may also be bonded to each other through a linking group, and at least one of the >NR and the >Si(-R)2 may also be bonded to the aryl ring or heteroaryl ring through a linking group or a single bond,

[0277] r is an integer from 1 to 4,

[0278] R A are independently hydrogen, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl, and any R A Can be connected to any other R A Bonded to each other.

[0279] Examples of the substituent include substituents represented by any of the following.

[0280]

[0281] In each formula, the * only needs to be bonded to two or three consecutive (adjacent) atoms on any aryl ring or heteroaryl ring.

[0282] <Cycloalkane Condensation>

[0283] Substituents substituted at adjacent atoms in the aryl ring and heteroaryl ring of the polycyclic aromatic compound including the structural unit represented by formula (1) may be bonded to each other to form a ring. The aspect that substituted or unsubstituted alkyl groups substituted at adjacent atoms are bonded to each other to form a ring also manifests itself as condensation of cycloalkanes.

[0284] At least one of the aryl rings and heteroaryl rings selected from the group consisting of the polycyclic aromatic compound containing the structural unit represented by Chemical Formula 1 may be condensed into at least one cycloalkane. The same is true for the polycyclic aromatic compound represented by Formula (1X1), and the following description is also applicable to the polycyclic aromatic compound represented by any of these formulas.

[0285] The cycloalkane may be a cycloalkane having 3 to 24 carbon atoms. In this case, at least one hydrogen in the cycloalkane may be substituted by an aryl group having 6 to 30 carbon atoms, a heteroaryl group having 2 to 30 carbon atoms, an alkyl group having 1 to 24 carbon atoms, or a cycloalkyl group having 3 to 24 carbon atoms, and at least one -CH2- in the corresponding cycloalkane may be substituted by -O-.

[0286] The cycloalkane is a cycloalkane having 3 to 20 carbon atoms, and preferably a cycloalkane in which at least one hydrogen atom in the cycloalkane may be substituted by an aryl group having 6 to 16 carbon atoms, a heteroaryl group having 2 to 22 carbon atoms, an alkyl group having 1 to 12 carbon atoms, or a cycloalkyl group having 3 to 16 carbon atoms.

[0287] Examples of the “cycloalkane” include cycloalkanes having 3 to 24 carbon atoms, cycloalkanes having 3 to 20 carbon atoms, cycloalkanes having 3 to 16 carbon atoms, cycloalkanes having 3 to 14 carbon atoms, cycloalkanes having 5 to 10 carbon atoms, cycloalkanes having 5 to 8 carbon atoms, cycloalkanes having 5 to 6 carbon atoms, and cycloalkanes having 5 carbon atoms.

[0288] Specific examples of cycloalkanes include cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclooctane, cyclononane, cyclodecane, norbornane (bicyclo[2.2.1]heptane), bicyclo[1.1.0]butane, bicyclo[1.1.1]pentane, bicyclo[2.1.0]pentane, bicyclo[2.1.1]hexane, bicyclo[3.1.0]hexane, bicyclo[2.2.2]octane, adamantane, diadamantane, decahydronaphthalene and decahydroazulene, as well as alkyl (especially methyl)-substituted, halogen (especially fluorine)-substituted and deuterium-substituted products having 1 to 5 carbon atoms.

[0289] In the example, for example, as shown in the following structural formula, it is preferred that the carbon at the α position of the cycloalkane (the carbon at the position adjacent to the carbon at the condensation site in the cycloalkane condensed by the aryl ring or the heteroaryl ring) has at least one substituent, and more preferably the carbon at the α position has two substituents, and further preferably the carbon at the 2 α positions has two substituents (a total of 4 substituents). As the substituent, alkyl (especially methyl) having 1 to 5 carbon atoms, halogen (especially fluorine) and deuterium can be listed. In particular, it is preferred to realize a structure in which a partial structure represented by the following formula (B11) or the following formula (B12) is bonded to adjacent carbon atoms in the aryl ring or the heteroaryl ring, and it is preferred to realize a structure in which a partial structure represented by the following formula (B11) is bonded.

[0290]

[0291] In formula (B11) and formula (B12), * represents a bonding position.

[0292] The number of cycloalkanes condensed with an aryl ring or a heteroaryl ring is preferably 1 to 3, more preferably 1 or 2, and further preferably 1. For example, an example of a benzene ring (phenyl) condensed into one or more cycloalkanes is shown below. * represents a bonding position, which can be any one of the carbons that constitute the benzene ring but do not constitute a cycloalkane. The cycloalkanes condensed as shown in formula (Cy-1-4) and formula (Cy-2-4) can also be condensed. Whether the condensed ring (base) is an aryl ring or a heteroaryl ring other than the benzene ring (phenyl), or the condensed cycloalkane is a cycloalkane other than cyclopentane or cyclohexane, it is the same.

[0293]

[0294] At least one -CH2- in the cycloalkane may be substituted with -O-. For example, the following shows an example in which one or more -CH2- in a cycloalkane condensed with a benzene ring (phenyl) is substituted with -O-. This is the same whether the condensed ring (base) is an aryl ring or heteroaryl ring other than the benzene ring (phenyl), or the condensed cycloalkane is a cycloalkane other than cyclopentane or cyclohexane.

[0295]

[0296] The cycloalkane may be substituted with at least one substituent, and as the substituent, any substituent selected from the substituent group Z may be cited. Among these substituents, alkyl groups (e.g., alkyl groups with 1 to 6 carbon atoms) and cycloalkyl groups (e.g., cycloalkyl groups with 3 to 14 carbon atoms) are preferred. In addition, it is also preferred that any one of the hydrogen groups is substituted with a halogen (e.g., fluorine) or deuterium. In addition, when the cycloalkyl group is substituted, it may also be a substitution form that forms a spiro ring structure, for example, an example of a cycloalkane condensed with a benzene ring (phenyl) forming a spiro ring structure is shown below. The * in each structural formula refers to the benzene ring contained in the skeleton structure of the compound in the case of a benzene ring, and refers to the bond bond that is substituted in the skeleton structure of the compound in the case of a phenyl group.

[0297]

[0298] As the form of cycloalkane condensation, first, there can be mentioned a form in which the aryl ring or heteroaryl ring in each of the A ring, the B ring and the C ring of the polycyclic aromatic compound including the structural unit represented by formula (1) is condensed into a cycloalkane, or a form in which the aryl ring or heteroaryl ring included in the substituent of the aryl ring or heteroaryl ring in each of the A ring, the B ring and the C ring is condensed into a cycloalkane.

[0299] In addition, polycyclic aromatic compounds including the structural unit represented by the formula (1) and the like can be exemplified by the formula (E ABC) in the substituent represented by ), the aryl ring or heteroaryl ring in each of the P ring and the Q ring is condensed into a cycloalkane, the aryl ring or heteroaryl ring included in the substituent of the aryl ring or heteroaryl ring in each of the P ring and the Q ring is condensed into a cycloalkane, or the aryl ring and heteroaryl ring in Ar are condensed into a cycloalkane.

[0300] In addition, by introducing a cycloalkane structure into a polycyclic aromatic compound including a structural unit represented by formula (1), a further reduction in the melting point or sublimation temperature can be expected. In sublimation purification, which is almost indispensable as a purification method for materials for organic devices such as organic EL elements that require high purity, since purification can be performed at a relatively low temperature, it means that thermal decomposition of the material can be avoided. In addition, this is also true for a powerful method for making organic devices such as organic EL elements, namely, a vacuum evaporation process, because the process can be carried out at a relatively low temperature, thermal decomposition of the material can be avoided, and a high-performance organic device can be finally obtained. In addition, since the introduction of a cycloalkane structure improves the solubility in organic solvents, it can be applied to the production of elements using a coating process. However, the present invention is not particularly limited to the above principle.

[0301] <Isotope Substitution>

[0302] All or part of the hydrogen in the polycyclic aromatic compound including the structural unit represented by formula (1) may be deuterium. The same applies to the polycyclic aromatic compound represented by formula (1X1). In addition, in the polycyclic aromatic compound including the structural unit represented by formula (1), at least one nitrogen may be 15 nitrogen( 15 N) substituted, at least one sulfur may be 33 sulfur( 33 S), 34 sulfur( 34 S) or 36 sulfur( 36 S) substituted, at least one oxygen may be 17 oxygen( 17 O) or 18 oxygen( 18 O) substitution, at least one carbon may be 13 carbon( 13 C) substituted, and at least one boron may be 11 boron( 11 B) Replacement.

[0303] For example, in the case where hydrogen atoms of the aryl or heteroaryl rings of the A, B and C rings or these substituents may be replaced by deuterium, examples include the case where all or part of the hydrogen atoms in the aryl or heteroaryl groups are replaced by deuterium. ABC) or the aryl ring and heteroaryl ring of Ar may be replaced by deuterium. In addition, from the viewpoint of durability, it is also preferred that all or part of the hydrogen in the polycyclic aromatic compound including the structural unit represented by formula (1) is deuterated.

[0304] <Specific examples of polycyclic aromatic compounds>

[0305] Examples of the polycyclic aromatic compound including the structural unit represented by the formula (1) include compounds represented by any of the following structural formulae.

[0306]

[0307]

[0308]

[0309]

[0310]

[0311]

[0312]

[0313]

[0314]

[0315]

[0316]

[0317]

[0318]

[0319]

[0320]

[0321]

[0322]

[0323]

[0324]

[0325]

[0326]

[0327]

[0328]

[0329]

[0330]

[0331]

[0332]

[0333]

[0334]

[0335]

[0336]

[0337]

[0338]

[0339]

[0340]

[0341]

[0342]

[0343]

[0344]

[0345]

[0346]

[0347]

[0348]

[0349]

[0350]

[0351]

[0352]

[0353]

[0354]

[0355]

[0356]

[0357]

[0358]

[0359]

[0360]

[0361]

[0362]

[0363]

[0364]

[0365]

[0366]

[0367]

[0368]

[0369]

[0370]

[0371]

[0372]

[0373]

[0374] <Method for manufacturing polycyclic aromatic compounds>

[0375] The polycyclic aromatic compound including the structural unit represented by formula (1) can be produced by first bonding the A ring, the B ring and the C ring using a bonding group (NJ) to produce an intermediate (first reaction), and then bonding the A ring, the B ring and the C ring using boron to produce a final product (second reaction). In the first reaction, for example, if it is an etherification reaction, general reactions such as nucleophilic substitution reaction and Ullmann reaction can be used, and if it is an amination reaction, general reactions such as Buchwald-Hartwig reaction, nucleophilic substitution reaction and Goldberg amination can be used. In addition, in the second reaction, a tandem hetero-Friedel-Crafts reaction (continuous aromatic electrophilic substitution reaction, the same below) can be used.

[0376] The second reaction is a reaction of introducing boron that bonds the A ring, the B ring, and the C ring, as shown in the following reaction formula (1). First, the halogen atoms between the nitrogen atoms can be exchanged with halogen metals using n-butyl lithium, sec-butyl lithium, or tert-butyl lithium. Then, boron trichloride or boron tribromide is added, and after the lithium-boron metal exchange is carried out, a Bronsted base such as N,N-diisopropylethylamine is added, so that a tandem boro-fried-crafts reaction can be carried out to obtain the target product. In the second reaction, a Lewis acid such as aluminum trichloride can be added to promote the reaction. In addition, Hal, that is, the halogen atom in the formula, can be any one of Cl, Br, and I, and can be appropriately selected considering the reactivity of the substrate.

[0377] [Reaction formula (1)]

[0378]

[0379] In addition, the reaction formula (1) is shown as an example of a method for producing a polycyclic aromatic compound represented by the formula (1X).

[0380] With the formula (E ABC The intermediate of the group represented by ) can be synthesized by referring to the method described in International Publication No. 2015 / 102118.

[0381] Furthermore, by appropriately selecting the raw materials to be used, a polycyclic aromatic compound having a substituent at a desired position can be synthesized.

[0382] In addition, the target substance can be obtained by preparing a part other than the partial structure represented by formula (X) by the same method as described in Advanced Material, 2022, 34, 2106954, and then borated and bonded with the halogen body of the partial structure represented by formula (X). Alternatively, the halogen body of the part other than the partial structure represented by formula (X) and the borate of the partial structure represented by formula (X) can also be used, and known halogen species and borates can be used appropriately.

[0383] Specific examples of the solvent used in the reaction include tert-butylbenzene and xylene.

[0384] In addition, in the synthesis method of the reaction formula (1), an example is shown in which a halogen-metal exchange is performed on the halogen atoms between nitrogen atoms using butyl lithium or the like before adding boron trichloride or boron tribromide, thereby performing a tandem hetero-Friedel-Crafts reaction. However, the reaction can also be performed by adding boron trichloride or boron tribromide as a precursor for converting the halogen into hydrogen.

[0385] In addition, examples of the ortho-metallating agent used in the reaction formula (1) include alkyl lithiums such as methyl lithium, n-butyl lithium, sec-butyl lithium, tert-butyl lithium, and the like, and organic alkali metal compounds such as lithium diisopropylamide, lithium tetramethylpiperidinide, lithium hexamethyldisilazide, and potassium hexamethyldisilazide.

[0386] Examples of the metal-boron metal exchange reagent used in the reaction formula (1) include boron halides such as boron trifluoride, boron trichloride, boron tribromide, and boron triiodide, boron alkoxides, and boron aryloxides.

[0387] In addition, examples of the Bronsted base used in the reaction formula (1) include N,N-diisopropylethylamine, triethylamine, 2,2,6,6-tetramethylpiperidine, 1,2,2,6,6-pentamethylpiperidine, N,N-dimethylaniline, N,N-dimethyltoluidine, 2,6-lutidine, sodium tetraphenylborate, potassium tetraphenylborate, triphenylborane, tetraphenylsilane, Ar4BNa, Ar4BK, Ar3B, Ar4Si (in addition, Ar is an aromatic group such as phenyl), etc.

[0388] Examples of the Lewis acid used in the reaction formula (1) include AlCl3, AlBr3, AlF3, BF3·OEt2, BCl3, BBr3, BI3, GaCl3, GaBr3, InCl3, InBr3, In(OTf)3, SnCl4, SnBr4, AgOTf, ScCl3, Sc(OTf)3, ZnCl2, ZnBr2, Zn(OTf)2, MgCl2, MgBr2, Mg(OTf)2, LiOTf, NaOTf, KOTf, Me3SiOTf, Cu(OTf)2, CuCl2, YCl3, Y(OTf)3, TiCl4, TiBr4, ZrCl4, ZrBr4, FeCl3, FeBr3, CoCl3, CoBr3, and the like.

[0389] In the reaction formula (1), in order to promote the tandem heterofried-crafts reaction, a Bronsted base or a Lewis acid may be used. However, when a boron halide such as boron trifluoride, boron trichloride, boron tribromide, or boron triiodide is used, as the aromatic electrophilic substitution reaction proceeds, acids such as hydrogen fluoride, hydrogen chloride, hydrogen bromide, or hydrogen iodide are generated, and therefore, it is effective to use a Bronsted base that captures the acid. On the other hand, when a boron amide halide or boron alkoxylate is used, since amines and alcohols are generated as the aromatic electrophilic substitution reaction proceeds, in most cases, it is not necessary to use a Bronsted base, but since the release energy of the amino or alkoxy group is low, it is effective to use a Lewis acid that promotes the release thereof.

[0390] In addition, the polycyclic aromatic compounds of the present invention also include compounds in which at least a portion of hydrogen atoms are substituted by deuterium, or compounds in which halogens such as fluorine or chlorine are substituted. However, such compounds can be synthesized in the same manner as described above by using deuterated, fluorinated or chlorinated raw materials for the desired portion.

[0391] 2. Organic Devices

[0392] The polycyclic aromatic compound of the present invention can be used as a material for an organic device. Examples of organic devices include organic electroluminescent elements, organic field effect transistors, and organic thin-film solar cells. The polycyclic aromatic compound of the present invention is preferably used as a material for forming one or more organic layers in an organic electroluminescent element.

[0393] 2-1. Organic electroluminescent element

[0394] 2-1-1. Structure of organic electroluminescent element

[0395] Figure 1 This is a schematic cross-sectional view showing an example of an organic EL element.

[0396] Figure 1The organic EL element 100 shown in the figure comprises: a substrate 101, an anode 102 arranged on the substrate 101, a hole injection layer 103 arranged on the anode 102, and a hole transport layer 104 arranged on the hole injection layer 103, a light-emitting layer 105 arranged on the hole transport layer 104, an electron transport layer 106 arranged on the light-emitting layer 105, and an electron injection layer 107 arranged on the electron transport layer 106, and a cathode 108 arranged on the electron injection layer 107.

[0397] The organic EL element 100 can also have a reverse manufacturing order to form, for example, the following structure, which comprises: a substrate 101, a cathode 108 arranged on the substrate 101, an electron injection layer 107 arranged on the cathode 108, and an electron transport layer 106 arranged on the electron injection layer 107, a light-emitting layer 105 arranged on the electron transport layer 106, a hole transport layer 104 arranged on the light-emitting layer 105, a hole injection layer 103 arranged on the hole transport layer 104, and an anode 102 arranged on the hole injection layer 103.

[0398] The above-mentioned layers are not all indispensable layers, and the minimum structural unit is set to include the anode 102, the light-emitting layer 105, and the cathode 108. The hole injection layer 103, the hole transport layer 104, the electron transport layer 106, and the electron injection layer 107 are layers that can be arbitrarily provided. In addition, the above-mentioned layers may each include a single layer or a plurality of layers.

[0399] The morphology of the layers constituting the organic EL element may be, in addition to the configuration of “substrate / anode / hole injection layer / hole transport layer / luminescent layer / electron transport layer / electron injection layer / cathode”, “substrate / anode / hole injection layer / luminescent layer / electron transport layer / electron injection layer / cathode”, “substrate / anode / hole injection layer / luminescent layer / electron transport layer / electron injection layer / cathode”, “substrate / anode / hole injection layer / hole transport layer / luminescent layer / electron injection layer / cathode”, “substrate / anode / hole injection layer / hole transport layer / luminescent layer / electron injection layer / cathode”, “substrate / anode / hole injection layer / hole transport layer / luminescent layer / electron injection layer / cathode”, The present invention relates to a composition pattern of substrate / anode / light-emitting layer / electron transport layer / cathode", "substrate / anode / light-emitting layer / electron transport layer / electron injection layer / cathode", "substrate / anode / hole transport layer / light-emitting layer / electron injection layer / cathode", "substrate / anode / hole transport layer / light-emitting layer / electron injection layer / cathode", "substrate / anode / hole injection layer / light-emitting layer / electron transport layer / cathode", "substrate / anode / hole injection layer / light-emitting layer / electron injection layer / cathode", "substrate / anode / light-emitting layer / electron transport layer / cathode", and "substrate / anode / light-emitting layer / electron injection layer / cathode".

[0400] The organic EL element may have any one or both selected from an electron blocking layer (electron blocking layer) and a hole blocking layer (hole blocking layer). The electron blocking layer has a LUMO that is shallower than the light-emitting layer and a HOMO that is close to the light-emitting layer or the hole transport layer, and is arranged between the light-emitting layer and the hole transport layer. Since the electrons stay in the light-emitting layer and do not leak into the hole transport layer, the shortening of the life due to the degradation of the hole transport layer and the reduction of the efficiency due to the reduction of the recombination efficiency can be prevented. The hole blocking layer has a HOMO that is deeper than the light-emitting layer and a LUMO that is close to the light-emitting layer or the hole transport layer, and is arranged between the light-emitting layer and the electron transport layer. Since the holes stay in the light-emitting layer and do not leak into the electron transport layer, the shortening of the life due to the degradation of the electron transport layer and the reduction of the efficiency due to the reduction of the recombination efficiency can be prevented. The hole injection·transport layer may also serve as the electron blocking layer. The electron injection·transport layer may also serve as the hole blocking layer.

[0401] The organic EL element may have a high T1 layer. The high T1 layer has a higher T1 than the main compound, auxiliary dopant compound or emission dopant compound used in the light-emitting layer, and is arranged between the light-emitting layer and the hole transport layer and / or between the light-emitting layer and the electron blocking layer. The value of the T1 energy varies depending on the light-emitting mechanism of the element, but has a higher T1 than the compound used in the main body. By having a high T1 layer around the light-emitting layer, the triplet energy can be confined, and the triplet energy that is not connected to the light emission in the conventional fluorescent molecules can be converted into singlet energy, thereby obtaining high efficiency. The hole injection·transport layer or the electron blocking layer can also serve as the high T1 layer. The electron injection·transport layer or the hole blocking layer can also serve as the high T1 layer.

[0402] The polycyclic aromatic compound of the present invention is preferably used as a material for forming a light-emitting layer or a material for forming an electron transport layer, and is more preferably used as a material for forming a light-emitting layer.

[0403] 2-1-2. Substrate for organic electroluminescent element

[0404] The substrate 101 is a support of the organic EL element 100, and quartz, glass, metal, plastic, etc. are generally used. Depending on the purpose, the substrate 101 is formed in a plate, film or sheet shape, for example, a glass plate, a metal plate, a metal foil, a plastic film, a plastic sheet, etc. are used. Among them, glass plates and plates made of transparent synthetic resins such as polyester, polymethacrylate, polycarbonate, polysulfone, etc. are preferred. In the case of a glass substrate, soda lime glass or alkali-free glass, etc. can be used, and the thickness is also sufficient to maintain mechanical strength. In addition, in order to improve the gas barrier properties, a dense gas barrier film such as a silicon oxide film can be formed on at least one side (one side) of the substrate 101. In particular, when a plate, film or sheet made of a synthetic resin with low gas barrier properties is used as the substrate 101, it is preferred to form a gas barrier film.

[0405] 2-1-3. Anode of organic electroluminescent element

[0406] The anode 102 plays a role of injecting holes into the light-emitting layer 105. On the other hand, when at least one of the hole injection layer 103 and the hole transport layer 104 is provided between the anode 102 and the light-emitting layer 105, holes are injected into the light-emitting layer 105 through these layers.

[0407] As materials for forming the anode 102, inorganic compounds and organic compounds can be cited. As inorganic compounds, for example, metals (aluminum, gold, silver, nickel, palladium, chromium, etc.), metal oxides (indium oxide, tin oxide, indium-tin oxide (indium tin oxide, ITO), indium-zinc oxide (indium zinc oxide, IZO), etc.), metal halides (copper iodide, etc.), copper sulfide, carbon black, ITO glass or Nessa glass, etc., can be cited. As organic compounds, for example, polythiophenes such as poly(3-methylthiophene), conductive polymers such as polypyrrole and polyaniline, etc., can be cited. In addition, it can be appropriately selected and used from the substances used as the anode of the organic EL element.

[0408] 2-1-4. Hole injection layer and hole transport layer of organic electroluminescent element

[0409] The hole injection layer 103 plays a role in efficiently injecting holes migrated from the anode 102 into the light-emitting layer 105 or the hole transport layer 104. The hole transport layer 104 plays a role in efficiently transporting holes injected from the anode 102 or holes injected from the anode 102 through the hole injection layer 103 to the light-emitting layer 105. The hole injection layer 103 and the hole transport layer 104 are formed by stacking or mixing one or more hole injection / transport materials. In addition, the layer can be formed by adding an inorganic salt such as iron (III) chloride to the hole injection / transport material.

[0410] As a hole injection and transport material, it is necessary to efficiently inject and transport holes from the positive electrode between the electrodes to which an electric field is applied, and it is preferred that the hole injection efficiency is high and the injected holes are efficiently transported. For this purpose, it is preferred that the material has a small ionization potential, a large hole mobility, and excellent stability, and is unlikely to produce impurities that become traps during manufacture and use.

[0411] As materials for forming the hole injection layer 103 and the hole transport layer 104, any compound can be selected and used from compounds conventionally used as charge transport materials for holes in photoconductive materials and known compounds used for hole injection layers and hole transport layers of p-type semiconductors and organic EL elements. Specific examples of these materials include carbazole derivatives (N-phenylcarbazole, polyvinylcarbazole, etc.), biscarbazole derivatives such as bis(N-arylcarbazole) or bis(N-alkylcarbazole), triarylamine derivatives (polymers having aromatic tertiary amino groups on the main chain or side chain, 1,1-bis(4-di-p-tolylaminophenyl)cyclohexane, N,N'-diphenyl-N,N'-di(3-methylphenyl)-4,4'-diaminobiphenyl, N,N'-diphenyl-N,N'-dinaphthyl-4,4'-diaminobiphenyl, N,N'-diphenyl-N,N'-di(3-methylphenyl)-4,4'-diphenyl-1,1'-diamine, N,N'-dinaphthyl-N,N'-diphenyl-4,4'-diphenyl-1,1'-diamine, N 4 ,N 4 '-Diphenyl-N 4 ,N 4 '-Bis(9-phenyl-9H-carbazole-3-yl)-[1,1'-biphenyl]-4,4'-diamine, N 4 ,N 4 ,N 4 ',N 4 '-tetrakis[1,1'-biphenyl]-4-yl-[1,1'-biphenyl]-4,4'-diamine, triphenylamine derivatives such as 4,4',4"-tris(3-methylphenyl(phenyl)amino)triphenylamine, starburst amine derivatives, etc.), stilbene derivatives, phthalocyanine derivatives (metal-free, copper phthalocyanine, etc.), pyrazoline derivatives, hydrazine compounds, benzofuran derivatives or thiophene derivatives, oxadiazole derivatives, quinoxaline derivatives (for example, 1,4,5,8,9,12-hexaazatriphenylene-2,3,6,7,10,11-hexacarbonitrile, etc.), heterocyclic compounds such as porphyrin derivatives, polysilane, etc. In the polymer system, polycarbonate or styrene derivatives, polyvinylcarbazole and polysilane having the above-mentioned monomers on the side chain are preferred, but there is no particular limitation as long as it is a compound that can form a thin film required for the production of a light-emitting element, can inject holes from the anode, and can further transport holes.

[0412] In addition, it is also known that the conductivity of organic semiconductors is strongly affected by their doping. The organic semiconductor matrix material as described above contains a compound with good electron donating properties or a compound with good electron accepting properties. In order to dope electron donating substances, strong electron acceptors such as tetracyanoquinonedimethane (TCNQ) or 2,3,5,6-tetrafluorotetracyano-1,4-benzoquinonedimethane (F4TCNQ) are known (for example, reference "M. Pfeiffer, A. Bayer, T. Fritz, K. Leo, "Applied Physics Letters" (M. Pfeiffer, A. Beyer, T. Fritz, K. Leo, Appl. Phys. Lett.) 73 (22), 3202 to 3204 (1998)", and the document "J. Blochwitz, M. Pfeiffer, T. Fritz, K. Leo, Appl. Phys. Lett.), 73 (6), 729 to 731 (1998)"). These so-called holes are generated through the electron migration process in the electron-donating base material (hole transport material). The conductivity of the base material will vary significantly depending on the number and mobility of the holes. As host materials having hole transport properties, for example, benzidine derivatives (TPD, etc.) or starburst amine derivatives (4,4',4"-tris(N,N-diphenylamino)triphenylamine (4,4',4"-Tris(N,N-diphenylamino)triphenylamine, TDATA), etc.), or specific metal phthalocyanines (especially zinc phthalocyanine (ZnPc), etc.) are known (Japanese Patent Publication No. 2005-167175).

[0413] The hole injection layer material and the hole transport layer material can be used as the following polymer compound or its polymer crosslinked product, or the following pendant type polymer compound or its pendant type polymer crosslinked product for the hole layer material, wherein the polymer compound is obtained by polymerizing a reactive compound substituted with a reactive substituent as a monomer, and the pendant type polymer compound is obtained by reacting a main chain polymer with the reactive compound.

[0414] 2-1-5. Light-emitting layer of organic electroluminescent element

[0415] The light-emitting layer 105 is a layer that emits light by allowing holes injected from the anode 102 and electrons injected from the cathode 108 to recombine between electrodes to which an electric field is applied. The material forming the light-emitting layer 105 can be any compound (luminescent compound) that is excited and emits light by the recombination of holes and electrons, and preferably a compound that can form a stable thin film shape and exhibits strong light-emitting (fluorescence) efficiency in a solid state.

[0416] The light-emitting layer may include a single layer or multiple layers, and each layer is formed of a light-emitting layer material. When the light-emitting layer includes multiple layers, preferably any one layer contains the polycyclic aromatic compound of the present invention. Preferably, the light-emitting layer is a single layer.

[0417] The light-emitting layer is formed by materials for the light-emitting layer (main material, dopant material). The main material and the dopant material may be one kind or a combination of multiple kinds, either of which is acceptable. For example, as dopant materials, emitting dopants and auxiliary dopants can be used. In addition, the light-emitting layer preferably comprises at least two selected from the group consisting of emitting dopants, hole-transporting main materials, electron-transporting main materials and auxiliary dopant materials. The dopant material is contained in the whole of the main material or partially contained in the main material, either of which is acceptable. As a doping method, it can be formed by co-evaporation with the main material, but it can be mixed with the main material in advance and then evaporated simultaneously. In addition, the light-emitting layer can also be formed by a wet film-forming method using a composition for forming a light-emitting layer prepared by dissolving the material in an organic solvent.

[0418] The amount of the host material used varies depending on the type of the host material and can be determined according to the characteristics of the host material. The standard for the amount of the host material used is preferably 50% to 99.999% by mass of the total mass of the material for the light-emitting layer, and more preferably 80% to 99.95% by mass, and further preferably 90% to 99.9% by mass. When the host material is a combination of a hole-transporting host material and an electron-transporting host material, the amount of the host material used is the mass of the hole-transporting host material and the electron-transporting host material added together. The ratio of the amount of the hole-transporting host material to the electron-transporting host material used is such that the mass ratio is 1:9 to 9:1, preferably 4:6 to 6:4, and more preferably about 1:1.

[0419] The amount of the emitting dopant used varies depending on the type of the emitting dopant and can be determined according to the characteristics of the emitting dopant. The standard for the amount of the emitting dopant used is preferably 0.001% to 50% by mass relative to the total mass of the material for the light-emitting layer, more preferably 0.05% to 20% by mass, and further preferably 0.1% to 10% by mass. If it is within the above range, it is preferred, for example, in terms of preventing concentration quenching.

[0420] For an organic electroluminescent element using an auxiliary dopant (thermally active delayed phosphor or phosphorescent material) other than an emitting dopant, it is preferred that the amount of the emitting dopant material used is low in order to prevent concentration quenching. It is preferred that the amount of the auxiliary dopant used is high in terms of energy transfer efficiency. It is preferred that the amount of the auxiliary dopant used is high in terms of the efficiency of the thermally active delayed fluorescent device. For an organic electroluminescent element using a thermally active delayed phosphor as an auxiliary dopant, it is preferred that the amount of the emitting dopant used is low in terms of the efficiency of the thermally active delayed fluorescent device of the auxiliary dopant, compared with the amount of the auxiliary dopant used.

[0421] When using auxiliary dopant materials, the usage standards of the main material, auxiliary dopant material and emission dopant material are 40 mass % to 99 mass %, 59 mass % to 1 mass % and 20 mass % to 0.001 mass %, respectively, relative to the total mass of the material for the light-emitting layer, preferably 60 mass % to 95 mass %, 39 mass % to 5 mass % and 10 mass % to 0.01 mass %, respectively, and further preferably 70 mass % to 90 mass %, 29 mass % to 10 mass % and 5 mass % to 0.05 mass %.

[0422] The polycyclic aromatic compound including the structural unit represented by the formula (1) is preferably used as a material for forming the light-emitting layer, more preferably as a dopant, and particularly preferably as an emissive dopant.

[0423] The polycyclic aromatic compound including the structural unit represented by formula (1) can be used as an emissive dopant of a TTF element utilizing a phenomenon (Triplet-Triplet Fusion (TTF)) in which a singlet exciton is generated from a plurality of triplet excitons.

[0424] In addition, a polycyclic aromatic compound including a structural unit represented by formula (1) can be used as an emitting dopant of a TADF element as a "thermally active delayed phosphor". In a "thermally active delayed phosphor", by reducing the energy difference between the lowest excited singlet state and the lowest excited triplet state, a reverse intersystem crossing from the lowest excited triplet state, which usually has a low mobility, to the lowest excited singlet state can be efficiently generated, thereby achieving luminescence from the singlet state (thermally active delayed fluorescence, TADF). In normal fluorescent luminescence, 75% of triplet excitons generated by current excitation pass through a thermal deactivation path and therefore cannot be extracted as fluorescence. On the other hand, in TADF, all excitons can be used for fluorescent luminescence, thereby achieving a highly efficient organic EL element.

[0425] Generally speaking, it is believed that delayed fluorescence has excellent TADF properties. Specifically, when a light-emitting material with a delayed fluorescence lifetime of 100 μsec or less is used as an emission dopant in a light-emitting element, high element efficiency and long element lifetime can be imparted. The delayed fluorescence lifetime is preferably less than 20 μsec, more preferably less than 10 μsec, and most preferably less than 5 μsec.

[0426] In addition, generally speaking, ΔE S1T1 The smaller the value of , the better the TADF property. On the other hand, ΔE S1T1 is the lowest excited singlet energy level (E S1 ) and the lowest excited triplet energy level (E T1 ) energy difference. Specifically, ΔE S1T1 The value of is preferably 0.20 eV or less, more preferably 0.15 eV or less, and particularly preferably 0.10 eV or less.

[0427] <Main material>

[0428] As the host material, condensed ring derivatives such as anthracene or pyrene, bis-styryl derivatives such as bis-styryl anthracene derivatives or distyryl benzene derivatives, tetraphenyl butadiene derivatives, cyclopentadiene derivatives, fluorene derivatives, benzofluorene derivatives, N-phenyl carbazole derivatives, carbazole nitrile derivatives, etc., which have been known as luminophores, can be cited. In addition, from the viewpoint of durability, it is preferred that part or all of the hydrogen atoms of the host material are deuterated. In addition, it is also preferred that the light-emitting layer is formed by combining a host compound in which part or all of the hydrogen atoms are deuterated with a dopant compound in which part or all of the hydrogen atoms are deuterated.

[0429] The host material may be one type or a combination of two or more types. When the host material is a combination of two or more types, a combination of a hole-transporting host material and an electron-transporting host material is preferred.

[0430] <Anthracene compounds>

[0431] Examples of the host anthracene compound include a compound represented by the formula (3-H) and a compound represented by the formula (3-H2).

[0432]

[0433] In formula (3-H),

[0434] X and Ar 4are each independently hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted diarylamino, substituted or unsubstituted diheteroarylamino, substituted or unsubstituted arylheteroarylamino, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted alkenyl, substituted or unsubstituted alkoxy, substituted or unsubstituted aryloxy, substituted or unsubstituted arylthio, or substituted silyl, and all X and Ar are 4 It will not become hydrogen at the same time.

[0435] At least one hydrogen in the compound represented by the formula (3-H) may be substituted with a halogen, a cyano group, a deuterium group or a substitutable heteroaryl group.

[0436] In addition, the structure represented by formula (3-H) can also be used as a unit structure to form a polymer (preferably a dimer). In the above case, for example, the unit structures represented by formula (3-H) are bonded by X, and as the X, a single bond, an arylene group (phenylene, biphenylene and naphthylene, etc.) and a heteroarylene group (a pyridine ring, a dibenzofuran ring, a dibenzothiophene ring, a carbazole ring, a benzocarbazole ring and a phenyl-substituted carbazole ring having a divalent bonding valence, etc.) can be listed.

[0437] The details of each group in the compound represented by the formula (3-H) can be referred to the description of the above formula (1), and will be described in the following preferred embodiment.

[0438] Preferred embodiments of the anthracene compound are described below. The definitions of the symbols in the following structures are the same as those described above.

[0439]

[0440] In formula (3-H), X is independently a group represented by formula (3-X1), formula (3-X2) or formula (3-X3), and the group represented by formula (3-X1), formula (3-X2) or formula (3-X3) is bonded to the anthracene ring of formula (3-H) at *. Preferably, two Xs are not simultaneously a group represented by formula (3-X3). More preferably, two Xs are not simultaneously a group represented by formula (3-X2).

[0441] In addition, the structure represented by formula (3-H) can also be used as a unit structure to form a polymer (preferably a dimer). In the above case, for example, the unit structures represented by formula (3-H) are bonded by X, and as the X, a single bond, an arylene group (phenylene, biphenylene and naphthylene, etc.) and a heteroarylene group (a pyridine ring, a dibenzofuran ring, a dibenzothiophene ring, a carbazole ring, a benzocarbazole ring and a phenyl-substituted carbazole ring having a divalent bonding valence, etc.) can be listed.

[0442] The naphthylene moieties of formula (3-X1) and formula (3-X2) can be condensed with one benzene ring. The structure formed by condensation in this manner is shown below.

[0443]

[0444] Ar 1 and Ar 2 are independently hydrogen, phenyl, biphenyl, terphenyl, quaterphenyl, naphthyl, phenanthryl, fluorenyl, benzofluorenyl, A group represented by formula (A) (including a carbazolyl group, a benzocarbazolyl group, and a carbazolyl group substituted with a phenyl group). 1 or Ar 2 In the case of a group represented by the formula (A), the group represented by the formula (A) is bonded to the naphthalene ring in the formula (3-X1) or the formula (3-X2) at the * thereof.

[0445] Ar 3 is phenyl, biphenyl, terphenyl, quaterphenyl, naphthyl, phenanthryl, fluorenyl, benzofluorenyl, A group represented by formula (A) (including a carbazole group, a benzocarbazole group, and a carbazole group substituted with a phenyl group). 3 In the case of a group represented by formula (A), the group represented by formula (A) is bonded to the single bond represented by the straight line in formula (3-X3) at the *. That is, the anthracene ring of formula (3-H) is directly bonded to the group represented by formula (A).

[0446] In addition, Ar 3 may have a substituent, and Ar 3 At least one hydrogen in the alkyl group may be replaced by an alkyl group having 1 to 4 carbon atoms, a cycloalkyl group having 5 to 10 carbon atoms, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a phenanthrenyl group, a fluorenyl group, substituted by a phenyl group, a triphenylene group, a pyrene group, or a group represented by formula (A) (including a carbazolyl group and a carbazolyl group substituted by a phenyl group). 3 When the substituent possessed is a group represented by formula (A), the group represented by formula (A) is in a position * with Ar in formula (3-X3) 3 Bond.

[0447] Ar 4 Preferably, each is independently hydrogen, phenyl, biphenyl, terphenyl, naphthyl, or a silyl group substituted with an alkyl group having 1 to 4 carbon atoms (such as methyl, ethyl, and tert-butyl) and / or a cycloalkyl group having 5 to 10 carbon atoms.

[0448] Examples of the alkyl group having 1 to 4 carbon atoms which is substituted in the silyl group include methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl, and cyclobutyl. Three hydrogen atoms in the silyl group are independently substituted with these alkyl groups.

[0449] Specific examples of the "silyl group substituted with an alkyl group having 1 to 4 carbon atoms" include trimethylsilyl, triethylsilyl, tripropylsilyl, triisopropylsilyl, tributylsilyl, tri-sec-butylsilyl, tri-tert-butylsilyl, ethyldimethylsilyl, propyldimethylsilyl, isopropyldimethylsilyl, butyldimethylsilyl, sec-butyldimethylsilyl, tert-butyldimethylsilyl, methyldiethylsilyl, propyldimethylsilyl, isopropyldimethylsilyl, butyldimethylsilyl, sec-butyldimethylsilyl, tert-butyldimethylsilyl, tert-butyldiethylsilyl, methyldipropylsilyl, ethyldipropylsilyl, butyldipropylsilyl, sec-butyldipropylsilyl, tert-butyldipropylsilyl, methyldiisopropylsilyl, ethyldiisopropylsilyl, butyldiisopropylsilyl, sec-butyldiisopropylsilyl, tert-butyldiisopropylsilyl and the like.

[0450] Examples of the cycloalkyl group having 5 to 10 carbon atoms which is substituted in the silyl group include cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, bicyclo[1.1.1]pentyl, bicyclo[2.1.0]pentyl, bicyclo[2.1.1]hexyl, bicyclo[3.1.0]hexyl, bicyclo[2.2.1]heptyl (norbornyl), bicyclo[2.2.2]octyl, adamantyl, decahydronaphthyl, decahydroazulenyl, and the like, and the three hydrogen atoms in the silyl group are independently substituted by these cycloalkyl groups.

[0451] Specific examples of the "silyl group substituted with a cycloalkyl group having 5 to 10 carbon atoms" include a tricyclopentylsilyl group and a tricyclohexylsilyl group.

[0452] The substituted silyl group includes a dialkylcycloalkylsilyl group in which two alkyl groups and one cycloalkyl group are substituted, and an alkyldicycloalkylsilyl group in which one alkyl group and two cycloalkyl groups are substituted. Specific examples of the substituted alkyl group and cycloalkyl group include those mentioned above.

[0453] In addition, hydrogen in the chemical structure of the anthracene compound represented by formula (3-H) may also be substituted by a group represented by formula (A). In the case of substitution by a group represented by formula (A), the group represented by formula (A) is substituted at its * by at least one hydrogen in the compound represented by formula (3-H).

[0454] The group represented by the formula (A) is one of substituents which the anthracene compound represented by the formula (3-H) may have.

[0455]

[0456] In formula (A), Y is -O-, -S- or >NR 29 , R 21 To R 28 are each independently hydrogen, an optionally substituted alkyl group, an optionally substituted cycloalkyl group, an optionally substituted aryl group, an optionally substituted heteroaryl group, an optionally substituted alkoxy group, an optionally substituted aryloxy group, an optionally substituted arylthio group, a trialkylsilyl group, a tricycloalkylsilyl group, a dialkylcycloalkylsilyl group, an alkyldicycloalkylsilyl group, an optionally substituted amino group, a halogen group, a hydroxyl group or a cyano group, and R 21 To R 28 The adjacent groups in the group may be bonded to each other to form a hydrocarbon ring, an aromatic ring or a heteroaromatic ring, and R 29 is hydrogen or an aryl group which may be substituted.

[0457] Y in formula (A) is preferably -O-.

[0458] R 21 To R 28 In the adjacent bases can be bonded to each other to form a hydrocarbon ring, an aryl ring or a heteroaryl ring. The case where a ring is not formed is a base represented by the following formula (A-1), and as the case of forming a ring, for example, the base represented by the following formula (A-2) to the formula (A-14) can be cited. In addition, at least one hydrogen in the base represented by any one of formulas (A-1) to (A-14) can be substituted by an alkyl, cycloalkyl, aryl, heteroaryl, alkoxy, aryloxy, arylthio, trialkylsilyl, tricycloalkylsilyl, dialkylcycloalkylsilyl, alkyldicycloalkylsilyl, diaryl (two aryl groups can be bonded to each other by a connecting group) substituted amino, diheteroaryl substituted amino, arylheteroaryl substituted amino, halogen, hydroxyl or cyano.

[0459]

[0460] Examples of the ring formed by bonding adjacent groups include a hydrocarbon ring, such as a cyclohexane ring, and examples of the aryl ring or heteroaryl ring include the above-mentioned R 21 To R 28 The ring structures described in the "aryl" or "heteroaryl" in formula (A-1) are formed by condensing with one or two benzene rings.

[0461] The group represented by formula (A) is a group obtained by removing a hydrogen atom at any position in formula (A), and * represents the position. That is, the group represented by formula (A) can use any position as a bonding position. For example, it can be a group that is bonded to any carbon atom on the two benzene rings in the structure of formula (A), R 21To R 28 The atoms on any one of the rings formed by bonding adjacent groups in the formula (A) or the NR 29 " 29 Any position in, or ">NR 29 "N(R 29 The same applies to the group represented by any one of the formulae (A-1) to (A-14).

[0462] As the group represented by formula (A), for example, a group represented by any one of formula (A-1) to formula (A-14) can be mentioned, preferably a group represented by any one of formula (A-1) to formula (A-5) and formula (A-12) to formula (A-14), more preferably a group represented by any one of formula (A-1) to formula (A-4), further preferably a group represented by any one of formula (A-1), formula (A-3) and formula (A-4), and particularly preferably a group represented by formula (A-1).

[0463] Examples of the group represented by formula (A) include the following groups: Y and * in the formula have the same meanings as above.

[0464]

[0465] In the compound represented by formula (3-H), the group represented by formula (A) is preferably in a naphthalene ring in formula (3-X1) or formula (3-X2), a single bond in formula (3-X3) and Ar in formula (3-X3). 3 The bonding form of any one of them.

[0466] In addition, all or part of the hydrogen in the chemical structure of the anthracene compound represented by the formula (3-H) may be deuterium.

[0467] The anthracene compound as a host may be, for example, a compound represented by the following formula (3-H2).

[0468]

[0469] In formula (3-H2), Ar c is an aryl group which may be substituted or a heteroaryl group which may be substituted, R c is hydrogen, alkyl or cycloalkyl, and Ar 11 ,Ar 12 ,Ar 13 ,Ar 14 ,Ar 15 ,Ar 16 ,Ar 17 , and Ar 18Each of them is independently hydrogen, a substitutable aryl, a substitutable heteroaryl, a substitutable diarylamino, a substitutable diheteroarylamino, a substitutable arylheteroarylamino, a substitutable alkyl, a substitutable cycloalkyl, a substitutable alkenyl, a substitutable alkoxy, a substitutable aryloxy, a substitutable arylthio, or a substitutable silyl, and at least one hydrogen in the compound represented by formula (3-H2) may be substituted by halogen, cyano or deuterium.

[0470] In formula (3-H2), the definitions of “substitutable aryl”, “substitutable heteroaryl”, “substitutable diarylamino”, “substitutable diheteroarylamino”, “substitutable arylheteroarylamino”, “substitutable alkyl”, “substitutable cycloalkyl”, “substitutable alkenyl”, “substitutable alkoxy”, “substitutable aryloxy”, “substitutable arylthio”, or “substitutable silyl” are the same as those of the compound represented by formula (3-H), and the description in formula (3-H) can be cited.

[0471] As the "aryl group which may be substituted", a group represented by any one of the following formula (3-H2-X1) to formula (3-H2-X8) is also preferred.

[0472]

[0473] In formula (3-H2-X1) to formula (3-H2-X8), * represents a bonding position. In formula (3-H2-X1) to formula (3-H2-X3), Ar 21 ,Ar 22 and Ar 23 are independently hydrogen, phenyl, biphenyl, terphenyl, quaterphenyl, naphthyl, phenanthryl, fluorenyl, benzofluorenyl, In the description of formula (3-H2), the group represented by formula (A) is the same as that of the anthracene compound represented by formula (3-H).

[0474] In formula (3-H2-X4) to formula (3-H2-X8), Ar 24 ,Ar 25 ,Ar 26 ,Ar 27 ,Ar 28 ,Ar 29 and Ar 30 are independently hydrogen, phenyl, biphenyl, terphenyl, naphthyl, phenanthryl, fluorenyl, In addition, any one or two or more hydrogen atoms in each of the groups represented by formula (3-H2-X1) to formula (3-H2-X8) may be substituted by an alkyl group having 1 to 6 carbon atoms (preferably a methyl group or a tert-butyl group).

[0475] Preferred examples of the "aryl group which may be substituted" include phenyl, biphenyl, terphenyl, naphthyl, phenanthrenyl, fluorenyl, 1, 2, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35

[0476] As the "heteroaryl group which may be substituted", the group represented by formula (A) can also be mentioned. In addition, as specific examples of the "aryl group which may be substituted" and the "heteroaryl group which may be substituted", dibenzofuranyl, naphthobenzofuranyl, phenyl-substituted dibenzofuranyl, etc. can be mentioned.

[0477] At least one hydrogen in the compound represented by formula (3-H2) may be substituted by halogen, cyano or deuterium. In this case, "halogen" includes fluorine, chlorine, bromine and iodine. Particularly preferred are compounds in which all hydrogens in the compound represented by formula (3-H2) are substituted by deuterium.

[0478] In formula (3-H2), R c It is hydrogen, alkyl or cycloalkyl, and is preferably hydrogen, methyl or tert-butyl, and more preferably hydrogen.

[0479] In formula (3-H2), Ar 11 To Ar 18 At least two of them are preferably substituted aryl groups or substituted heteroaryl groups. That is, the anthracene compound represented by formula (3-H2) preferably has a structure in which at least three substituents are bonded to the anthracene ring, and the substituents are selected from the group consisting of substituted aryl groups and substituted heteroaryl groups.

[0480] The anthracene compound represented by the formula (3-H2) is more preferably Ar 11 To Ar 18 In the formula (3-H2), two of the anthracene compounds are substituted aryl groups or substituted heteroaryl groups, and the other six are hydrogen, substituted alkyl groups, substituted cycloalkyl groups, substituted alkenyl groups, or substituted alkoxy groups. That is, the anthracene compound represented by the formula (3-H2) is more preferably a structure having three substituents bonded to the anthracene ring, wherein the substituents are selected from the group consisting of substituted aryl groups and substituted heteroaryl groups.

[0481] The anthracene compound represented by the formula (3-H2) is more preferably Ar 11 To Ar 18Any two of them are aryl which may be substituted or heteroaryl which may be substituted, and the other six are hydrogen, methyl or tert-butyl.

[0482] In the formula (3-H2), R c is hydrogen, and Ar 11 To Ar 18 Any 6 of them are hydrogen.

[0483] The anthracene compound represented by formula (3-H2) is preferably an anthracene compound represented by the following formula (3-H2-A), formula (3-H2-B), formula (3-H2-C), formula (3-H2-D) or formula (3-H2-E).

[0484]

[0485] In formula (3-H2-A), formula (3-H2-B), formula (3-H2-C), formula (3-H2-D) or formula (3-H2-E), Ar c '、Ar 11 '、Ar 12 '、Ar 13 '、Ar 14 '、Ar 15 '、Ar 17 ', and Ar 18 'are independently phenyl, biphenyl, terphenyl, quaterphenyl, naphthyl, phenanthryl, fluorenyl, benzofluorenyl, phenyl, biphenyl, terphenyl, quaterphenyl, naphthyl, phenanthryl, fluorenyl, benzofluorenyl, Here, when all hydrogen atoms of the methylene groups in the fluorenyl group and the benzofluorenyl group are substituted by phenyl groups, the phenyl groups may be bonded to each other via single bonds. c '、Ar 11 '、Ar 12 '、Ar 13 '、Ar 14 '、Ar 15 '、Ar 17 ', and Ar 18 A methyl group or a tert-butyl group may be bonded to the carbon atom of the anthracene ring in place of hydrogen.

[0486] Ar c '、Ar 11 '、Ar 12 '、Ar 13 '、Ar 14 '、Ar 15 '、Ar 17 ', and Ar18 When ' is a substituted or unsubstituted phenyl group or a substituted or unsubstituted naphthyl group, it is preferably a group represented by any one of the formulas (3-H2-X1) to (3-H2-X8).

[0487] Ar c '、Ar 11 '、Ar 12 '、Ar 13 '、Ar 14 '、Ar 15 '、Ar 17 ', and Ar 18 'More preferably, they are independently phenyl, biphenyl (especially biphenyl-2-yl or biphenyl-4-yl), terphenyl (especially m-terphenyl-5'-yl), naphthyl, phenanthrenyl, fluorenyl, or a group represented by any one of the formulas (A-1) to (A-4), in which case, at least one hydrogen in these groups may be substituted by phenyl, biphenyl, naphthyl, phenanthrenyl, fluorenyl, or a group represented by any one of the formulas (A-1) to (A-4).

[0488] In addition, at least one hydrogen in the compound represented by formula (3-H2-A), formula (3-H2-B), formula (3-H2-C), formula (3-H2-D), or formula (3-H2-E) may be substituted by halogen, cyano, or deuterium. In addition, the deuterated form is preferably a form in which all anthracene rings are deuterated, or a form in which all hydrogen atoms are deuterated.

[0489] As particularly preferred anthracene compounds represented by the formula (3-H2), anthracene compounds represented by the following formula (3-H2-Aa) can be mentioned.

[0490]

[0491] In the formula (3-H2-Aa), Ar c '、Ar 14 ' and Ar 15 'are independently phenyl, biphenyl, terphenyl, naphthyl, phenanthryl, fluorenyl, benzofluorenyl, A phenyl group, a triphenylene group, a pyrenyl group, or a group represented by any one of the formulas (A-1) to (A-11), at least one hydrogen in these groups may be replaced by a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a phenanthryl group, a fluorenyl group, a benzofluorenyl group, phenyl, triphenylene, pyrenyl, or a group represented by any one of formula (A-1) to formula (A-11). Here, when the hydrogen atoms of the methylene groups in the fluorenyl group and the benzofluorenyl group are substituted by phenyl groups, these phenyl groups may be bonded to each other via single bonds. c '、Ar 14 ' and Ar 15A methyl group or a tert-butyl group may be substituted at a carbon atom on the anthracene ring of ' to replace hydrogen. At least one hydrogen in the compound represented by the formula (3-H2-Aa) may be substituted by a halogen or a cyano group, and at least one hydrogen in the compound represented by the formula (3-H2-Aa) may be substituted by deuterium.

[0492] In the formula (3-H2-Aa), Ar c '、Ar 14 ' and Ar 15 'Preferably, they are independently phenyl, biphenyl, terphenyl, naphthyl, phenanthryl, fluorenyl, or a group represented by any one of the formulas (A-1) to (A-4), and at least one hydrogen in these groups may be substituted by a phenyl, naphthyl, phenanthryl, fluorenyl, or a group represented by any one of the formulas (A-1) to (A-4).

[0493] In the compound represented by the formula (3-H2-Aa), it is preferred that at least the carbon atom at the 10-position of the anthracene ring (Ar c 'The carbon to which it is bonded is set to the 9-position) and the hydrogen bonded is replaced by deuterium. That is, the compound represented by the formula (3-H2-Aa) is preferably a compound represented by the following formula (3-H2-Ab). In the formula (3-H2-Ab), D is deuterium, Ar c '、Ar 14 ' and Ar 15 ' is the same as the definition in formula (3-H2-Aa). D in formula (3-H2-Ab) means that at least the position is deuterated, and any one or more other hydrogens in formula (3-H2-Ab) may be deuterated at the same time, and preferably all hydrogens in formula (3-H2-Ab) are deuterated.

[0494]

[0495] As specific examples of anthracene compounds, for example, compounds represented by formula (3-131-Y) to formula (3-182-Y), compounds represented by formula (3-183-N), formula (3-184-Y) to (3-284-Y), and formula (3-500) to formula (3-557), and formula (3-600) to formula (3-605), and formula (3-606-Y) to formula (3-626-Y). The hydrogen atoms in these formulas may be partially or completely replaced by deuterium, but in particular, preferred deuterium-substituted forms are listed separately. When Y in the formula is -O-, -S-, >NR 29 (R 29 as defined above) or>C(-R 30 )2(R 30 is any of an aryl group or an alkyl group that can be connected, R 29 For example, phenyl, R 30For example, methyl. Regarding the formula number, for example, when Y is O, the formula (3-131-Y) is set to the formula (3-131-O), and when Y is -S- or >NR 29 In the case of, set it to formula (3-131-S) or formula (3-131-N) respectively.

[0496]

[0497]

[0498]

[0499]

[0500]

[0501]

[0502]

[0503]

[0504]

[0505]

[0506]

[0507]

[0508]

[0509]

[0510]

[0511]

[0512]

[0513]

[0514]

[0515]

[0516] In the formula, D is deuterium.

[0517] Among these compounds, preferred are compounds of formula (3-131-Y) to formula (3-134-Y), formula (3-138-Y), formula (3-140-Y) to formula (3-143-Y), formula (3-150-Y), formula (3-153-Y) to formula (3-156-Y), formula (3-166-Y), formula (3-168-Y), formula (3-173-Y), formula (3-177-Y), formula (3-180-Y) to formula (3-183-N), formula (3-185-Y), formula (3-190-Y), formula (3-223-Y), and formula (3-241-Y), formula (3-250-Y), formula (3-252-Y) to formula (3-254-Y), formula (3-270-Y) to formula (3-284-Y), formula (3-501), formula (3-507), formula (3-508), formula (3-509), formula (3-513), formula (3-514), formula (3-519), formula (3-521), formula (3-538) to formula (3-547) or formula (3-600) to formula (3-605) and formula (3-606-Y) to formula (3-626-Y) represented by the compound. In addition, Y is preferably -O-, or>NR 29 , more preferably -O-. In addition, a deuterium-substituted form is also preferred.

[0518] As long as the anthracene compound has a reactive group at a desired position of the anthracene skeleton and is represented by the formula (3-H), X, Ar 4 The invention relates to a method for preparing a catalytically active ...

[0519] <Fluorene compounds>

[0520] The compound represented by formula (4-H) substantially functions as a host.

[0521]

[0522] In formula (4-H),

[0523] R 1 To R 10are independently hydrogen, aryl, heteroaryl (the heteroaryl may be bonded to the fluorene skeleton in formula (4-H) via a linker), diarylamino, diheteroarylamino, arylheteroarylamino, alkyl, cycloalkyl, alkenyl, alkoxy or aryloxy, at least one hydrogen in these groups may be substituted by an aryl, heteroaryl, alkyl or cycloalkyl group, and R 1 With R 2 , R 2 With R 3 , R 3 With R 4 , R 5 With R 6 , R 6 With R 7 , R 7 With R 8 or R 9 With R 10 They may be independently bonded to form a condensed ring or a spiro ring, at least one hydrogen in the formed ring may be substituted by an aryl group, a heteroaryl group (the heteroaryl group may be bonded to the formed ring via a linker), a diarylamino group, a diheteroarylamino group, an arylheteroarylamino group, an alkyl group, a cycloalkyl group, an alkenyl group, an alkoxy group or an aryloxy group, at least one hydrogen in these may be substituted by an aryl group, a heteroaryl group, an alkyl group or a cycloalkyl group, at least one hydrogen in the compound represented by formula (4-H) may be substituted by a halogen, a cyano group or a deuterium.

[0524] The details of each group in the definition of formula (4-H) can be referred to the description of the polycyclic aromatic compound of formula (1) described above.

[0525] As R 1 To R 10 The alkenyl in the group includes, for example, an alkenyl having 2 to 30 carbon atoms, preferably an alkenyl having 2 to 20 carbon atoms, more preferably an alkenyl having 2 to 10 carbon atoms, further preferably an alkenyl having 2 to 6 carbon atoms, and particularly preferably an alkenyl having 2 to 4 carbon atoms. Preferred alkenyl groups are vinyl, 1-propenyl, 2-propenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-pentenyl, 2-pentenyl, 3-pentenyl, 4-pentenyl, 1-hexenyl, 2-hexenyl, 3-hexenyl, 4-hexenyl, or 5-hexenyl.

[0526] In addition, specific examples of heteroaryl groups include monovalent groups represented by removing any one hydrogen atom from the compounds of the following formula (4-Ar1), formula (4-Ar2), formula (4-Ar3), formula (4-Ar4) or formula (4-Ar5).

[0527]

[0528] In Formula (4-Ar1) to Formula (4-Ar5), Y 1are independently O, S or NR, R is phenyl, biphenyl, naphthyl, anthracenyl or hydrogen, and at least one hydrogen in the structures of Formula (4-Ar1) to (4-Ar5) may be substituted by phenyl, biphenyl, naphthyl, anthracenyl, phenanthryl, methyl, ethyl, propyl or butyl.

[0529] These heteroaryl groups can be bonded to the fluorene skeleton in formula (4-H) via a linking group. That is, the fluorene skeleton in formula (4-H) is not only directly bonded to the heteroaryl group, but also bonded between them via a linking group. Examples of the linking group include: phenylene, biphenylene, naphthylene, anthracene, methylene, ethylene, -OCH2CH2-, -CH2CH2O- or -OCH2CH2O-.

[0530] In addition, R in formula (4-H) 1 With R 2 , R 2 With R 3 , R 3 With R 4 , R 5 With R 6 , R 6 With R 7 or R 7 With R 8 can be independently bonded to form a condensed ring, R 9 With R 10 Can bond to form a spiro ring. 1 To R 8 The condensed ring formed is a ring condensed with the benzene ring in formula (4-H) and is an aliphatic ring or an aromatic ring. An aromatic ring is preferred, and examples of the structure including the benzene ring in formula (4-H) include a naphthalene ring and a phenanthrene ring. 9 With R 10 The spiro ring formed is a ring spiro-bonded to the 5-membered ring in formula (4-H) and is an aliphatic ring or an aromatic ring. An aromatic ring is preferred, and examples thereof include a fluorene ring.

[0531] The compound represented by formula (4-H) is preferably a compound represented by the following formula (4-H-1), formula (4-H-2) or formula (4-H-3), and R in formula (4-H) is 1 With R 2 The compound formed by condensation of the benzene ring formed by the bonding, in formula (4-H) R 3 With R 4 The compound formed by condensation of the benzene ring formed by the bonding, in formula (4-H) R 1 To R 8 All unbonded compounds.

[0532]

[0533] R in formula (4-H-1), formula (4-H-2) and formula (4-H-3) 1 To R 10 The definition of is the same as that of R in formula (4-H) 1 To R 10 The same, and R in formula (4-H-1) and formula (4-H-2) 11 To R 14 The definition of R is also the same as that of R in formula (4-H) 1 To R 10 same.

[0534] The compound represented by formula (4-H) is further preferably a compound represented by the following formula (4-H-1A), formula (4-H-2A) or formula (4-H-3A), and R in formula (4-H-1), formula (4-H-2) or formula (4-H-3) is 9 With R 10 A compound that is bonded to form a spiro-fluorene ring.

[0535]

[0536] R in formula (4-H-1A), formula (4-H-2A) and formula (4-H-3A) 2 To R 7 The definition of R is the same as that of R in formula (4-H-1), formula (4-H-2) and formula (4-H-3) 2 To R 7 The same, and R in formula (4-H-1A) and formula (4-H-2A) 11 To R 14 The definition of is also the same as R in formula (4-H-1) and formula (4-H-2) 11 To R 14 same.

[0537] In addition, all or part of hydrogen in the compound represented by the formula (4-H) may be substituted with halogen, cyano or deuterium.

[0538] More specific examples of the main fluorene compound of the present invention include compounds represented by the following structural formulas.

[0539]

[0540] [Dibenzo Compound]

[0541] As the main The compound is, for example, a compound represented by the following formula (5-H).

[0542]

[0543] In formula (5-H), R 1 To R 16 are independently hydrogen, aryl, heteroaryl (the heteroaryl can be connected to the dibenzoylmethane in formula (5-H) through a connecting group skeleton bond), diarylamino, diheteroarylamino, arylheteroarylamino, alkyl, cycloalkyl, alkenyl, alkoxy or aryloxy, at least one hydrogen in these groups may be substituted by an aryl, heteroaryl, alkyl or cycloalkyl group, and R 1 To R 16 Adjacent groups in the formula (5-H) may be bonded to form a condensed ring, at least one hydrogen in the formed ring may be substituted by an aryl group, a heteroaryl group (the heteroaryl group may be bonded to the formed ring via a connecting group), a diarylamino group, a diheteroarylamino group, an arylheteroarylamino group, an alkyl group, a cycloalkyl group, an alkenyl group, an alkoxy group or an aryloxy group, at least one hydrogen in these substituents may be substituted by an aryl group, a heteroaryl group, an alkyl group or a cycloalkyl group, and at least one hydrogen in the compound represented by the formula (5-H) may be substituted by a halogen, a cyano group or a deuterium group.

[0544] The details of each group in the definition of formula (5-H) can be referred to the description of the polycyclic aromatic compound of formula (1) described above.

[0545] As the alkenyl group in the definition of formula (5-H), for example, an alkenyl group having 2 to 30 carbon atoms can be mentioned, preferably an alkenyl group having 2 to 20 carbon atoms, more preferably an alkenyl group having 2 to 10 carbon atoms, further preferably an alkenyl group having 2 to 6 carbon atoms, and particularly preferably an alkenyl group having 2 to 4 carbon atoms. Preferred alkenyl groups are vinyl, 1-propenyl, 2-propenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-pentenyl, 2-pentenyl, 3-pentenyl, 4-pentenyl, 1-hexenyl, 2-hexenyl, 3-hexenyl, 4-hexenyl, or 5-hexenyl.

[0546] In addition, specific examples of heteroaryl groups include monovalent groups represented by removing any one hydrogen atom from the compounds of the following formula (5-Ar1), formula (5-Ar2), formula (5-Ar3), formula (5-Ar4) or formula (5-Ar5).

[0547]

[0548] In formula (5-Ar1) to formula (5-Ar5), Y 1 are independently O, S or NR, R is phenyl, biphenyl, naphthyl, anthracenyl or hydrogen, and at least one hydrogen in the structures of Formula (5-Ar1) to (5-Ar5) may be substituted by phenyl, biphenyl, naphthyl, anthracenyl, phenanthryl, methyl, ethyl, propyl or butyl.

[0549] These heteroaryl groups can be connected to the dibenzoylmethane in formula (5-H) through a linking group. That is, the dibenzo The skeleton and the heteroaryl group are not only directly bonded, but also bonded via a linker. Examples of the linker include phenylene, biphenylene, naphthylene, anthracene, methylene, ethylene, -OCH2CH2-, -CH2CH2O- or -OCH2CH2O-.

[0550] The compound represented by formula (5-H) is preferably R 1 , R 4 , R 5 , R 8 , R 9 , R 12 , R 13 and R 16 In the above case, R in formula (5-H) 2 , R 3 , R 6 , R 7 , R 10 , R 11 , R 14 and R 15 Preferably, each of them is independently hydrogen, phenyl, biphenyl, naphthyl, anthracenyl, phenanthryl, a monovalent group having a structure of the formula (5-Ar1), the formula (5-Ar2), the formula (5-Ar3), the formula (5-Ar4) or the formula (5-Ar5) (the monovalent group having the above structure can be connected with the dibenzofuran in the formula (5-H) through phenylene, biphenylene, naphthylene, anthracenyl, methylene, ethylene, -OCH2CH2-, -CH2CH2O- or -OCH2CH2O-) backbone bond), methyl, ethyl, propyl or butyl.

[0551] The compound represented by formula (5-H) is more preferably R 1 , R 2 , R 4 , R 5 , R 7 , R 8 , R 9 , R 10 , R 12 , R 13 , R 15 and R 16 In the above case, R in formula (5-H) 3 , R 6 , R 11 and R 14At least one of them (preferably one or two, more preferably one) is a monovalent group having a structure of formula (5-Ar1), formula (5-Ar2), formula (5-Ar3), formula (5-Ar4) or formula (5-Ar5) formed by a single bond, phenylene, biphenylene, naphthylene, anthracene, methylene, ethylene, -OCH2CH2-, -CH2CH2O- or -OCH2CH2O-, and other than the at least one (i.e., other than the position where the monovalent group having the structure is substituted) is hydrogen, phenyl, biphenyl, naphthyl, anthracene, methyl, ethyl, propyl or butyl, and at least one of these hydrogens may be substituted by phenyl, biphenyl, naphthyl, anthracene, methyl, ethyl, propyl or butyl.

[0552] In addition, when a monovalent group having a structure represented by formula (5-Ar1) to formula (5-Ar5) is selected as R in formula (5-H), 2 , R 3 , R 6 , R 7 , R 10 , R 11 , R 14 and R 15 In the case of, at least one hydrogen in the structure can be connected with R in formula (5-H) 1 To R 16 Any one of them is bonded to form a single bond.

[0553] The main dibenzoylmethane of the present invention More specific examples of the compound include compounds represented by the following structural formulas.

[0554]

[0555]

[0556] [Compound represented by any one of formula (H1), formula (H2) and formula (H3)]

[0557] As the host material, for example, a compound represented by any of the following formula (H1), formula (H2), and formula (H3) can be used.

[0558]

[0559] In formula (H1), formula (H2) and formula (H3), L 1 is a single bond or a divalent group containing at least an arylene group or a heteroarylene group. 1is a single bond, or an arylene group having 6 to 24 carbon atoms, a heteroarylene group having 2 to 24 carbon atoms, a heteroarylene arylene group having 6 to 24 carbon atoms, or an arylene heteroarylene group having 6 to 24 carbon atoms, or any two of them are -O-, -S-, -CH2-, -Si(-Ar x )2-(Ar x is an aryl group), or a divalent group formed by connecting a cycloalkylene group. 1 The arylene group in is preferably an arylene group having 6 to 16 carbon atoms, more preferably an arylene group having 6 to 12 carbon atoms, and particularly preferably an arylene group having 6 to 10 carbon atoms, and specifically includes divalent groups such as a benzene ring, a biphenyl ring, a terphenyl ring, and fluorene benzene. 1 The heteroarylene group in is preferably a heteroarylene group having 2 to 24 carbon atoms, more preferably a heteroarylene group having 2 to 20 carbon atoms, further preferably a heteroarylene group having 2 to 15 carbon atoms, and particularly preferably a heteroarylene group having 2 to 10 carbon atoms, and specifically includes: a pyrrole ring, an oxazole ring, an isoxazole ring, a thiazole ring, an isothiazole ring, an imidazole ring, an oxadiazole ring (such as a furazan ring), a thiadiazole ring, a triazole ring, a tetrazole ring, a pyrazole ring, a pyridine ring, a pyrimidine ring, a pyridazine ring, a pyrazine ring, a triazine ring, an indole ring, divalent groups such as isoindole ring, 1H-indazole ring, benzimidazole ring, benzoxazole ring, benzothiazole ring, 1H-benzotriazole ring, quinoline ring, isoquinoline ring, cinnoline ring, quinazoline ring, quinoxaline ring, phthalazine ring, naphthyridine ring, purine ring, pteridine ring, carbazole ring, acridine ring, phenoxathiol ring, phenoxazine ring, phenothiazine ring, phenazine ring, indolazine ring, furan ring, benzofuran ring, isobenzofuran ring, dibenzofuran ring, thiophene ring, benzothiophene ring, dibenzothiophene ring and thianthrene ring. At least one hydrogen of the compounds represented by the above formulae may be substituted with at least one group selected from the substituent group Z or deuterium, for example, with an alkyl group having 1 to 6 carbon atoms, a cyano group, a halogen group or deuterium.

[0560] As a preferred specific example, a compound represented by any of the following structural formulas can be cited. In addition, in the following structural formulas, at least one hydrogen can be substituted by halogen, cyano, alkyl having 1 to 4 carbon atoms (such as methyl or tert-butyl), phenyl or naphthyl.

[0561]

[0562]

[0563] [Hole-transporting host material (HH) and electron-transporting host material (EH)]

[0564] Regarding the highest occupied molecular orbital (Highest Occupied Molecular Orbital) and the lowest unoccupied molecular orbital (Lowest Unoccupied Molecular Orbital), the hole transporting host material (HH) and the electron transporting host material (EH) satisfy the following relationship.

[0565] The HOMO of the hole-transporting host material (HH) is shallower than the HOMO of the electron-transporting host material (EH), and the LUMO of the electron-transporting host material (EH) is deeper than the LUMO of the hole-transporting host material (HH).

[0566] In addition, it is preferred that the HOMO of the emissive dopant is shallower than the HOMO of the hole-transporting host material (HH), or the LUMO of the emissive dopant is deeper than the LUMO of the electron-transporting host material (EH).

[0567] In addition, from the viewpoint of not inhibiting but promoting the generation of TADF in the light-emitting layer, the lowest excited triplet energy level (E T1 ) is preferably higher than the light-emitting layer having the highest E T1 E of the emitting dopant or auxiliary dopant T1 High, specifically, preferably the E T1 than the E of the emitting dopant or the auxiliary dopant T1 It is higher by 0.01 eV or more, more preferably higher by 0.03 eV or more, and even more preferably higher by 0.1 eV or more. T1 It is preferably 2.47 eV or more, more preferably 2.49 eV or more, and further preferably 2.56 eV or more.

[0568] In addition, it is preferred to use a hole transporting host material in the hole transport layer adjacent to the light-emitting layer, and to use an electron transporting host material in the electron transport layer adjacent to the light-emitting layer. The reason is that it is difficult for carrier leakage and energy leakage to occur from the light-emitting layer to the adjacent layer, thereby obtaining a highly efficient organic EL element. The host material (hole transporting host material) in the light-emitting layer may be the same as or different from the hole transport layer material. In addition, the host material (electron transporting host material) in the light-emitting layer may be the same as or different from the material of the electron transport layer.

[0569] As examples of preferred hole transport host materials (HH), the following compounds can be cited: compounds represented by formula (HH-1) or having a partial structure represented by formula (HH-1) and having a structure including at least three rings selected from the group consisting of an aryl ring and a heteroaryl ring. The compounds preferably do not contain an imine structure (-N=C-; a ​​partial structure containing a heteroaryl ring), boron (>B-), and a cyano group (CN).

[0570]

[0571] In formula (HH-1),

[0572] Q is >O, >S, or >NA H ,

[0573] The carbon atoms adjacent to the carbon atom to which Q is bonded in each of the two phenyl groups in formula (HH-1) may be bonded to each other via L, where L is a single bond, >O, >S, or >C(-A H )2,

[0574] A H is hydrogen, aryl or heteroaryl, and>C(-A H )2 of 2 A H can be bonded to each other.

[0575] When the hole transport host material includes a structure represented by formula (HH-1) as a partial structure, it may include one partial structure, but preferably includes two or more. When it includes two or more, the two or more partial structures may be the same as each other or different. The two or more partial structures may be bonded to each other by a single bond, or they may be bonded in a manner that shares any ring included in the partial structure, and any ring included in the partial structure may be bonded in a manner that condenses. The partial structure may also have a substituent selected from an aryl group, a heteroaryl group, a diarylamino group or an aryloxy group.

[0576] The compound having a partial structure represented by the formula (HH-1) or represented by the formula (HH-1) has a structure of at least three rings selected from the group consisting of aryl rings and heteroaryl rings. The number of rings included is preferably 6 or more, more preferably 8 or more. In addition, it is preferably 20 or less, more preferably 15 or less, and further preferably 10 or less. The number of rings refers to the number of single rings, and for a condensed ring, it refers to the number of single rings constituting the condensed ring.

[0577] The hole transport host material is preferably a compound comprising one or more partial structures selected from the group consisting of: a triarylamine structure, a carbazole ring, a dibenzofuran ring, a dibenzothiophene ring, and a condensed polycyclic ring comprising phenoxazine or phenothiazine. The hole transport host material may comprise one partial structure as described above, but preferably comprises two or more partial structures. When comprising two or more partial structures, the two or more partial structures may be the same as each other, or may be different.

[0578] Specific examples of the hole-transporting host material include the following compounds.

[0579]

[0580]

[0581]

[0582]

[0583]

[0584]

[0585]

[0586]

[0587]

[0588]

[0589]

[0590]

[0591]

[0592] Among the above, preferred are HH-1-1, HH-1-2, HH-1-4 to HH-1-12, HH-1-17, HH-1-18, HH-1-20 to HH-1-24, HH-1-82, HH-1-84 to HH-1-89, HH-1-91, HH-1-92, HH-1-106 to HH-1-108 and HH-1-109 to HH-1-114.

[0593] As examples of electron transport host materials (EH), the following compounds can be listed: compounds having a partial structure represented by formula (EH-1A) to (EH-1D) or represented by formula (EH-1A) to (EH-1D) and having a structure comprising at least three rings selected from the group consisting of aromatic rings and heteroaryl rings.

[0594]

[0595] In formulas (EH-1A) to (EH-1D),

[0596] Ar is a heteroaryl ring containing N═C as a partial structure constituting the ring,

[0597] Z is a single bond, -O-, -S-, or -N(-A E )-,

[0598] The carbon atom next to the carbon atom to which Z is bonded is bound to the A atom to which Z is bonded. E can be bonded to each other through L,

[0599] L is a single bond, >O, >S or >C(-A E )2,

[0600] A E is aryl, heteroaryl or triarylsilyl, and>C(-A E )2 of 2 A E Can bond to each other,

[0601] X is C, P or S,

[0602] When X is C, n=2, m=1,

[0603] When X is P, n=3, m=1,

[0604] When X is S, n=2, m=1 to 2.

[0605] The compound having a partial structure represented by the formula (EH-1A) to the formula (EH-1D) or represented by the formula (EH-1A) to the formula (EH-1D) has a structure including at least three rings selected from the group consisting of aryl rings and heteroaryl rings. The number of rings included is preferably 4 or more, more preferably 6 or more, and further preferably 8 or more. In addition, it is preferably 20 or less, more preferably 15 or less, and further preferably 10 or less. The number of rings refers to the number as a single ring, and for a condensed ring, it refers to the number of single rings constituting the condensed ring.

[0606] When the electron transport host material includes a structure represented by formula (EH-1A) to formula (EH-1D) as a partial structure, one of the partial structures may be included, but it is also preferred to include two or more. When two or more are included, the two or more partial structures may be the same as each other, and may also be different. The two or more partial structures may be bonded to each other by a single bond, may be bonded in a manner that shares any ring contained in the partial structure, and may be bonded in a manner that condenses between any rings contained in the partial structure. The partial structure may also have a substituent selected from an aryl group, a heteroaryl group, a diarylamino group or an aryloxy group.

[0607] Specific examples of the electron transporting host material include the following compounds.

[0608]

[0609]

[0610]

[0611]

[0612]

[0613]

[0614]

[0615]

[0616] Other preferred examples of electron transport host materials (compounds having a partial structure represented by formula (EH-1)) include polycyclic aromatic compounds represented by the following formula (EH-1b) or polymers of polycyclic aromatic compounds having multiple structures represented by the following formula (EH-1b).

[0617]

[0618] In formula (EH-1b),

[0619] R 1 , R 2 , R 3 , R 4 and R 5 (hereinafter also referred to as “R 1 ", etc.) are each independently hydrogen or a substituent. The substituent may be a substituent selected from the substituent group Z.

[0620] In formula (EH-1b), X 1 and X 2are independently >NR (amine nitrogen), >O, >C(-R)2, >S or >Se, and X is absent 1 and X 2 All are >C(-R)2,

[0621] R in the >NR and >C(-R)2 is each independently hydrogen or a substituent selected from the substituent group Z, and may be further substituted by an aryl group, a heteroaryl group, an alkyl group or a cycloalkyl group (above, the second substituent), and R in the >NR and >C(-R)2 may each independently be bonded to at least one of the a ring, the b ring and the c ring through a linker or a single bond.

[0622] Y 1 , Y 2 , Y 3 , Y 4 , Y 5 and Y 6 (hereinafter also referred to as “Y 1 ", etc.) are independently =C(-R)- or =N-(pyridine nitrogen), and at least one of them is =N-(pyridine nitrogen),

[0623] The R in the ═C(—R)— is independently hydrogen or a substituent selected from the substituent group Z.

[0624] The R 1 , R 2 , R 3 , R 4 and R 5 , and as the Y 1 To Y 6 Adjacent groups in R of =C(-R)- may be bonded to each other and form an aryl ring or a heteroaryl ring together with at least one of the a ring, b ring and c ring, and at least one hydrogen in the formed ring may be substituted by an aryl group, a heteroaryl group, a diarylamino group, a diheteroarylamino group, an arylheteroarylamino group, a diarylboryl group (two aryl groups may be bonded via a single bond or a linker), an alkyl group, a cycloalkyl group, an alkoxy group, or an aryloxy group (above, the first substituent), and at least one hydrogen in these substituents may be further substituted by an aryl group, a heteroaryl group, an alkyl group or a cycloalkyl group (above, the second substituent).

[0625] At least one hydrogen in the compound and structure represented by formula (EH-1b) may be substituted with cyano, halogen or deuterium.

[0626] In formula (EH-1b), R 1 , R 2 , R 3 , R 4 and R 5 are hydrogen, or R 3 and R 4are hydrogen, and are preferably selected from R 1 , R 2 and R 5 Any one or more of the group of components is a substituent other than hydrogen and the rest is hydrogen. As a substituent, an alkyl group, an aryl group that can be substituted by an alkyl group or a heteroaryl group, a heteroaryl group that can be substituted by an alkyl group or an aryl group, or a diarylamino group that can be substituted by an alkyl group or an aryl group is preferred. At this time, as an alkyl group, an alkyl group having 1 to 6 carbon atoms (methyl, tert-butyl, etc.) is preferred, as an aryl group, a phenyl group or a biphenyl group is preferred, and as a heteroaryl group, a triazine group, a carbazolyl group (2-carbazolyl, 3-carbazolyl, 9-carbazolyl, etc.), a pyrimidinyl group, a pyridyl group, a dibenzofuranyl group or a dibenzothienyl group is preferred. As specific examples, phenyl, biphenyl, diphenyl triazine group, carbazolyl triazine group, monophenyl pyrimidinyl group, diphenyl pyrimidinyl group, carbazolyl triazine group, pyridyl group, dibenzofuranyl group and dibenzothienyl group can be cited.

[0627] Y 1 etc. are independently =C(-R)- or =N-, and at least one of them is =N-. 1 To Y 6 Any of may be =N-. Preferably, Y 1 and Y 6 =N-(ring a is a pyrimidine ring), Y 1 or Y 6 =N-(ring a is a pyrimidine ring), Y 2 and Y 5 =N- (ring b and ring c are pyrimidine rings), Y 3 and Y 4 =N- (ring b and ring c are pyrimidine rings), Y 2 To Y 5 =N- (ring b and ring c are pyrimidine rings), Y 1 , Y 3 , Y 4 and Y 6 =N- (ring a is a pyrimidine ring, ring b and ring c are pyridine rings), Y 1 , Y 2 , Y 5 and Y 6 =N- (ring a is a pyrimidine ring, ring b and ring c are pyridine rings), Y 1 To Y 6 =N- (ring a, ring b and ring c are pyrimidine rings), Y 2 or Y 5 =N- (the b ring or c ring is a pyridine ring).

[0628] In addition, in the above arrangement relationship of =N-, it is preferred that X 1 and X 2>0, and is preferably a polycyclic aromatic compound containing a partial structure represented by any one of the following formulae.

[0629]

[0630] In particular, the polycyclic aromatic compound containing the partial structure represented by the formula (EH-1b-N1) has a high E S1 , High E T1 , small ΔE S1T1 .

[0631] Specific examples of the polycyclic aromatic compound represented by formula (EH-1b) are shown below.

[0632]

[0633]

[0634]

[0635]

[0636]

[0637]

[0638] Among the above, EH-1-1 to EH-1-4, EH-1-10, EH-1-21 to EH-1-25, EH-1-32, EH-1-33, EH-1-51 to EH-1-59, EH-1-61, EH-1-66, EH-1-68, EH-1-7 1. EH-1-72, EH-1-90, EH-1-100, EH-1-101, EH-1-104, EH-1-115, EH-1-117, EH-1-120, EH-1-122, EH-1-123, EH-1-127 to EH-1-130.

[0639] [Combination of hole-transporting host material and electron-transporting host material]

[0640] The combination of the hole transporting host material and the electron transporting host material is composed of the HOMO, LUMO and the lowest excited triplet energy level (E T1 )choose.

[0641] Regarding HOMO and LUMO, a combination is selected in which the HOMO (HH) of the hole-transporting main material is shallower than the HOMO (EH) of the electron-transporting main material and the LUMO (EH) of the electron-transporting main material is deeper than the LUMO (HH) of the hole-transporting main material. More specifically, a combination in which HOMO (HH) is shallower than HOMO (EH) by at least 0.10 eV and LUMO (HH) is deeper than HOMO (EH) by at least 0.10 eV is preferred, a combination in which HOMO (HH) is shallower than HOMO (EH) by at least 0.20 eV and LUMO (HH) is deeper than HOMO (EH) by at least 0.20 eV is more preferred, and a combination in which HOMO (HH) is shallower than HOMO (EH) by at least 0.25 eV and LUMO (HH) is deeper than HOMO (EH) by at least 0.25 eV is further preferred.

[0642] The hole transporting main material and the electron transporting main material may be a combination forming a complex called an exciplex. As is well known, an exciplex is easily formed between a material with a relatively deep LUMO level and a material with a shallow HOMO level. The interaction between the hole transporting main material and the electron transporting main material, specifically whether an exciplex is formed, can be judged by the following method: a monolayer film containing only the hole transporting main material and the electron transporting main material is formed in the same manner as the formation conditions of the light-emitting layer, and the luminescence spectrum (fluorescence, phosphorescence spectrum) is measured, and the obtained luminescence spectrum is compared with the luminescence spectrum of the hole transporting main material and the electron transporting main material each separately. The spectrum of the mixed film containing the hole transporting main material and the electron transporting main material shows a different luminescence wavelength from any of the film spectra of the hole transporting main material and the film spectra of the electron transporting main material, so that it can be judged. Specifically, the peak wavelength of the spectrum differs by more than 10nm as an indicator.

[0643] Specific examples of the combination of a hole-transporting host material and an electron-transporting host material that do not form an exciplex include the following combinations. T1The physical property values ​​of, in the hole transport host material, preferably a compound having carbazole, dibenzofuran, dibenzothiophene, triarylamine, indolecarbazole and benzoxazine and phenoxazine as a partial structure, more preferably a compound having carbazole, dibenzofuran and dibenzothiophene as a partial structure, and further preferably a compound having carbazole as a partial structure. Similarly, in the electron transport host material, preferably a compound having pyridine, triazine, phosphine oxide, benzofuran pyridine and dibenzooxasilane as a partial structure, more preferably a compound having triazine, phosphine oxide, benzofuran pyridine and dibenzooxasilane as a partial structure, and further preferably a compound having triazine.

[0644] More specifically, the hole transport host material is preferably selected from the group consisting of HH-1-1, HH-1-2, HH-1-4 to HH-1-12, HH-1-17, HH-1-18, HH-1-20 to HH-1-24, HH-1-82, HH-1-84 to HH-1-89, HH-1-91, HH-1-92, HH-1-106 to HH-1-108 and HH-1-109 to HH-1-114, and the electron transport host material is preferably selected from the group consisting of EH-1- The group consisting of EH-1 to EH-1-4, EH-1-10, EH-1-21 to EH-1-25, EH-1-32, EH-1-33, EH-1-51 to EH-1-59, EH-1-61, EH-1-71, EH-1-72, EH-1-90, EH-1-100, EH-1-101, EH-1-104, EH-1-117, EH-1-120, EH-1-122, EH-1-123, and EH-1-127 to EH-1-130. Preferred examples of combinations include compound HH-1-1 and compound EH-1-22, compound HH-1-1 and compound EH-1-23, compound HH-1-1 and compound EH-1-24, compound HH-1-2 and compound EH-1-22, compound HH-1-2 and compound EH-1-23, compound HH-1-2 and compound EH-1-24, or compound HH-1-1 and compound EH-1-128.

[0645] As specific examples of the combination of a hole transporting host material and an electron transporting host material that form an exciplex, the following combinations can be cited. T1The physical property values ​​of, in the hole transport host material, preferably a compound having carbazole, triarylamine, indolecarbazole and benzoxazine and phenoxazine as a partial structure, more preferably a compound having triarylamine, indolecarbazole and benzoxazine and phenoxazine as a partial structure, and further preferably a compound having triarylamine as a partial structure. Similarly, in the electron transport host material, preferably a compound having pyridine, triazine, phosphine oxide and benzofuranopyridine as a partial structure, more preferably a compound having triazine, phosphine oxide, benzofuranopyridine and dibenzooxasilane as a partial structure, and further preferably a compound having phosphine oxide and triazine.

[0646] More specifically, the hole transport host material is preferably selected from the group consisting of HH-1-1, HH-1-2, HH-1-11, HH-1-12, HH-1-17, HH-1-18, HH-1-23 and HH-1-24, and the electron transport host material is preferably selected from the group consisting of EH-1-1 to EH-1-4, EH-1-21 to EH-1-25, EH-1-30 to EH-31. The group consisting of EH-1-51 to EH-1-57, EH-1-59, EH-1-66, EH-1-68, EH-1-90, EH-1-100, EH-1-101, EH-1-104, EH-1-117, EH-1-120, EH-1-122, EH-1-123 and EH-1-127 to EH-1-130. Preferred examples of combinations include compound HH-1-1 and compound EH-1-21, compound HH-1-2 and compound EH-1-21, compound H-1-12 and compound EH-1-117, compound HH-1-1 and compound EH-1-130, compound HH-1-33 and compound EH-1-117, compound HH-1-48 and compound EH-1-117, or compound HH-1-49 and compound EH-1-117.

[0647] In addition, for specific combinations of hole transport host materials and electron transport host materials, reference may be made to the following records: Organic Electronics 66 (2019) 227 to 24; Advanced Functional Materials 25 (2015) 361 to 366.; Advanced Materials 26 (2014) 4730 to 4734.; ACS Applied Materials and Interfaces 8 (2016) 32984 to 32991.; ACS Applied Materials and Interfaces 2016, 8, 9806 to 9810; ACS Applied Materials and Interfaces 2016, 8, 32984 to 32991; Journal of Materials Chemisty C, 2018, 6, 8784 to 8792; Angewandte Chemie International Edition.)2018, 57, 12380-12384; Advanced Functional Materials 24, 2014, 3970; Advanced Materials 26, 2014, 5684; Synthetic Metals 201, 2015, 49; and Nature Photonics, 16, 212-218 (2022).

[0648] <Assisting dopant (thermally active delayed phosphor or phosphorescent material)>

[0649] The light-emitting layer preferably contains an emitting dopant, a host material, and an auxiliary dopant. The auxiliary dopant is preferably a thermally active delayed fluorescent substance or a phosphorescent material.

[0650] In the TAF element or the PSF element, a polycyclic aromatic compound including the structural unit represented by the formula (1) may be preferably used as an emissive dopant.

[0651] In this aspect, as the main compound, a known compound can be used, for example, a compound having at least one of a carbazole ring and a furan ring, wherein it is preferred to use a compound in which at least one of a furanyl group and a carbazole group is bonded to at least one of an arylene group and a heteroarylene group. As a specific example, 1,3-di(carbazol-9-yl)benzene (1,3-di(carbazol-9-yl)benzene, mCP) or 3,3'-di(N-carbazolyl)-1,1'-biphenyl (3,3'-di(N-carbazolyl)-1,1'-biphenyl, mCBP) can be listed. In addition, for the main compound, a compound having TADF activity can also be used. In this aspect, it is also preferred to use a combination of a hole transporting main material and an electron transporting main material as the main body.

[0652] From the viewpoint of not hindering and promoting the generation of TADF in the light-emitting layer, the lowest excited triplet energy level E(1, T, Sh) obtained from the short-wavelength shoulder of the peak of the phosphorescence spectrum of the main compound is preferably higher than the lowest excited triplet energy levels E(2, T, Sh) and E(3, T, Sh) of the emitting dopant or auxiliary dopant having the highest lowest excited triplet energy level in the light-emitting layer. Specifically, the lowest excited triplet energy level E(1, T, Sh) of the main compound is preferably higher by 0.01 eV than E(2, T, Sh) and E(3, T, Sh), more preferably higher by 0.03 eV, and even more preferably higher by 0.1 eV.

[0653] [Thermally activated delayed phosphor]

[0654] "Thermal activation type delayed fluorescence" refers to a compound that can absorb thermal energy and undergo reverse intersystem crossing from the lowest excited triplet state to the excited singlet state, and radiatively deactivate from its lowest excited singlet state to emit delayed fluorescence. However, "thermal activation type delayed fluorescence" also includes a compound that undergoes a higher-order triplet state during the excitation process from the lowest excited triplet state to the lowest excited singlet state. For example, there can be cited a paper by Monkman et al. of Durham University (NATURE COMMUNICATIONS, 7: 13680, Digital Object Identifier (DOI): 10.1038 / ncomms 13680), a paper by Hosugai et al. of the National Institute of Advanced Industrial Science and Technology (Hosugai et al., Science Advances (Sci. Adv.) 2017; 3: e1603282), and a paper by Sato et al. of Kyoto University (Scientific Reports (Scientific Reports (Scientific Reports (Scientific Reports (Scientific Reports (Scientific Reports (Scientific Reports (Scientific Reports (Scientific Reports (Scientific Reports (Scientific Reports (Scientific Reports (Scientific Reports (Scientific Reports (Scientific Reports (Scientific Reports (Scientific Reports (Scientific Reports (Scientific Reports (Scientific Reports (Scientific Reports (Scientific Reports (Scientific Reports (Scientific Reports Reports, 7: 4820, DOI: 10.1038 / s41598-017-05007-7), also a society publication by Sato et al. from Kyoto University (98th Spring Annual Meeting of the Chemical Society of Japan, Publication No.: 2I4-15, Efficient luminescence mechanism in organic electroluminescence using DABNA as a luminescent molecule, Graduate School of Engineering, Kyoto University), a commentary by Bui et al. (DOI: 10.3762 / bjoc.14.18), a commentary by Duan et al. (DOI: 10.1063 / 1.5143501), a commentary by Ding et al. (DOI: 10.1088 / 1674-4926 / 42 / 5 / 050201), and a commentary by Xie et al. (DOI: 10.1002 / adom.202002204). In the present invention, when the fluorescence lifetime of a sample containing the target compound is measured at 300K, the target compound is determined to be a "thermally active delayed fluorescent substance" based on the observation of a slow fluorescence component. Here, the slow fluorescence component refers to a fluorescence component with a fluorescence lifetime of 0.1 μsec or more. The measurement of fluorescence lifetime can be performed using, for example, a fluorescence lifetime measurement device (manufactured by Hamamatsu Photonics, C11367-01).

[0655] In the light-emitting layer further comprising a "thermally active delayed phosphor" as an auxiliary dopant, the polycyclic aromatic compound of the present invention can function as an emitting dopant. That is, the "thermally active delayed phosphor" can function as an auxiliary dopant that assists the light emission of the polycyclic aromatic compound of the present invention.

[0656] In this specification, an organic electroluminescent element using a thermally activated delayed phosphor as an assisting dopant may be referred to as a "TAF element" (TADF Assisting Fluorescence element).

[0657] The “host compound” in the TAF element refers to a compound having a lower lowest excited singlet energy level obtained from the shoulder on the short-wavelength side of the peak of the fluorescence spectrum than that of the thermally active delayed phosphor and the emitting dopant as auxiliary dopants.

[0658] The thermally active delayed phosphor (TADF compound) used in the TAF element is preferably a donor-acceptor type thermally active delayed phosphor (DA-type TADF compound) designed in a manner that uses an electron-donating substituent called a donor and an electron-accepting substituent called an acceptor to localize the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) in the molecule so as to produce effective reverse intersystem crossing.

[0659] Here, in this specification, an “electron donating substituent” (donor) refers to a substituent and a partial structure that exist locally at the HOMO in a thermally active delayed phosphor molecule, and an “electron accepting substituent” (acceptor) refers to a substituent and a partial structure that exist locally at the LUMO in a thermally active delayed phosphor molecule.

[0660] Generally speaking, the structure of thermally activated delayed fluorescent materials using donors or acceptors has a large spin orbit coupling (SOC) and a small exchange interaction between HOMO and LUMO, resulting in a large ΔE S1T1 Small, so a very fast reverse intersystem crossing speed can be achieved.

[0661] By using the polycyclic aromatic compound of the present invention as an emission dopant and a thermally active delayed phosphor (TADF material) as an auxiliary dopant, an element that satisfies any one or all of high efficiency, high color purity and long life can be provided. The thermally active delayed phosphor can be any compound whose emission spectrum at least partially overlaps with the absorption spectrum of the polycyclic aromatic compound of the present invention. The polycyclic aromatic compound of the present invention and the thermally active delayed phosphor can be contained in the same layer, and can also be contained in adjacent layers or other adjacent layers.

[0662] As the thermally active delayed phosphor in the TAF element, for example, a compound in which a donor and an acceptor are bonded directly or through a spacer can be used. As the electron donating group (donor structure) and electron accepting group (acceptor structure) used in the thermally active delayed phosphor of the present invention, for example, the structure described in Chemistry of Materials, 2017, 29, 1946 to 1963 can be used. Examples of donor structures include carbazole, dimethylcarbazole, di-tert-butylcarbazole, dimethoxycarbazole, tetramethylcarbazole, benzofluorocarbazole, benzothiophenecarbazole, phenyldihydroindolecarbazole, phenylbicarbazole, bicarbazole, tertiary carbazole, diphenylcarbazole-based amine, tetraphenylcarbazole-based diamine, phenoxazine, dihydrophenazine, phenothiazine, dimethyldihydroacridine, diphenylamine, bis(tert-butylphenyl)amine, N1-(4-(diphenylamino)phenyl)-N4,N4-diphenylbenzene-1,4-diamine, dimethyltetraphenyldihydroacridine diamine, tetramethyl-dihydro-indenoacridine and diphenyldihydrodibenzoazepine silane. Examples of the acceptor structure include sulfonyl diphenyl, benzophenone, phenylene bis(phenyl ketone), benzonitrile, isonicotinonitrile, phthalonitrile, isophthalonitrile, terephthalonitrile, benzene trimonitrile, triazole, oxazole, thiadiazole, benzothiazole, benzobis(thiazole), benzoxazole, benzobis(oxazole), quinoline, benzimidazole, dibenzoquinoxaline, heptazaphenalene, thioxanthone dioxide, dimethyl anthrone, anthracenedione, 5H cyclopenta[1,2-b:5,4-b']dipyridine, fluorene dicarbonitrile, triphenyl triazine, pyrazine dicarbonitrile, pyrimidine, phenyl pyrimidine, methyl pyrimidine, pyridine dicarbonitrile, dibenzoquinoxaline dicarbonitrile, bis(phenylsulfonyl)benzene, dimethylthioxanthene dioxide, thianthrene tetraoxide and tris(dimethylphenyl)borane. In particular, the compound having thermally activated delayed fluorescence in the TAF element is preferably a compound having at least one selected from the following as a partial structure: carbazole, phenoxazine, acridine, triazine, pyrimidine, pyrazine, thioxanthene, benzonitrile, phthalonitrile, isophthalonitrile, diphenyl sulfone, triazole, oxadiazole, thiadiazole and benzophenone.

[0663] The compound used as an auxiliary dopant in the light-emitting layer of the TAF device is preferably a thermally activated delayed phosphor, and is preferably a compound whose emission spectrum at least partially overlaps with the absorption peak of the emitting dopant.

[0664] [Phosphorescent materials (auxiliary dopants)]

[0665] In the light-emitting layer, a phosphorescent material can be used as an auxiliary dopant. In this specification, an organic electroluminescent element using a phosphorescent material as an auxiliary dopant is sometimes referred to as a phosphorescent auxiliary element: a phosphor-sensitized fluorescent element, a PSF element. The phosphorescent material utilizes the intramolecular spin-orbit interaction (heavy atom effect) caused by metal atoms to obtain light emission from an excited triplet state. As such a phosphorescent material, for example, a luminescent metal complex can be used.

[0666] Examples of the light-emitting metal complex include compounds represented by the following formula (B-1) and the following formula (B-2).

[0667]

[0668] In formula (B-1), M is at least one selected from the group consisting of Ir, Pt, Au, Eu, Ru, Re, Ag and Cu, n is an integer from 1 to 3, and "XY" are each independently a 2-position ligand.

[0669] In formula (B-2), M is at least one selected from the group consisting of Pt, Re and Cu, and "WXYZ" is a 4-position ligand.

[0670] In formula (B-1), M is preferably Ir and n is preferably 3 from the viewpoint of efficiency and life.

[0671] In formula (B-2), M is preferably Pt from the viewpoint of efficiency and life.

[0672] The ligand (XY) in formula (B-1) has at least one ligand selected from the group consisting of: The ligand (WXYZ) in formula (B-2) has at least one ligand selected from the group consisting of: as a part.

[0673]

[0674] In the formula,

[0675] For ---, bonded to the central metal M,

[0676] Y is independently BR e NR e , PR e ,O,S,Se,C=O,S=O,SO2,CR e R f 、SiR e R f , or GeR e R f, the aromatic carbon CH in the ring can be independently replaced by N,

[0677] R e and R f Can be condensed or bonded to form a ring,

[0678] R a , R b , R c , and R d may be unsubstituted or substituted by 1 to the maximum number of substitutions,

[0679] R a , R b , R c , R d , R e and R f are independently hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroaryl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, aryl, heteroaryl, nitrile, isonitrile, thio or a combination thereof,

[0680] However, R a , R b , R c and R d Any two adjacent substituents in the ligand may be condensed or bonded to form a ring, or to form a multi-position ligand.

[0681] Examples of the compound represented by formula (B-1) include tris(2-phenylpyridine)iridium (Ir(ppy)3), bis(2-phenylpyridine)(acetylacetonate) (Ir(ppy)2(acac)), tris[2-(p-tolyl)pyridine]iridium (Ir(mppy)3), bis(2-phenylpyridine)[2-(diphenyl-3-yl)pyridine]iridium (Ir(PPy)2(m-bppy)), (2-(2'-benzothienyl)-pyridine-N,C3')(acetylacetonate)iridium (BtpIr(acac)), bis(2-(2'-benzothienyl)pyridine-N,C3' Ir(btp)2(acac)), Ir(2-phq)3), Ir(2-(4-n-hexylphenyl)quinoline)iridium (Hex-Ir(phq)3), Ir(fbi)2(acac)), Ir(2-(9,9-diethyl-fluoren-2-yl)-1-phenyl-1H-benzo[d]imidazole), Ir(btp)2(acac), Ir(2-(2-quinolyl)phenyl)iridium (III) (fac-Tris(2-(3-p-xylyl)phenyl)pyridine iridium(III)), tris(1,3-diphenyl-1,3-propanedione)mono(1,10-phenanthroline)europium (Eu(dbm)3(Phen)), tris(1-phenyl-isoquinoline)iridium (Ir(piq)3), bis(1-phenyl-isoquinoline)(acetylacetonate)iridium (Ir(piq)2(acac)), bis[1-(9,9-dimethyl-9H-fluoren-2-yl)-isoquinoline](acetylacetonate)iridium (Ir(Fliq)2(acac)), bis[2-(9,9-dimethyl-9H-fluoren-2-yl)quinoline](acetylacetonate)iridium (Ir(Flq)2(acac)), tris[4,4'-bis(tert-butyl)-2,2'-bipyridyl]ruthenium hexafluorophosphate (R u(dtb-bpy)3·2(PF6)), tris[2-(2-quinolyl)phenyl]iridium (Ir(2-phq)3), bis(2-phenylbenzothiazole)(acetylacetonate)iridium (Ir(BT)2(acac)), tris(2,2',6,6'-tetramethyl-3,5-heptanedione)iridium (Ir(DMP)3), bis(2-phenylquinoline)(2-(3-methylphenyl)pyridine)iridium (Ir(Mphq)3IR(phq)2tpy), bis(2-phenylpyridine)(3-(pyridin-2-yl)-2H-isochromene-2-one)iridium (fac-Ir(ppy)2Pc), Ir(dp)PQ2, bis(phenylisoquinoline)(2,2,6,6-tetramethylheptane-3,5-diacid ester) iridium (Ir(Dpm)(Piq)2), bis[(4-n-hexylphenyl)isoquinoline](acetylacetonate)iridium (Hex-Ir(piq)2(acac)), tris[5-hexyl-2-(1-isoquinolyl)phenyl]iridium (Hex-Ir(piq)3), tris(2-(3,5-dimethylphenyl)quinoline-C2,N')iridium (Ir(dmpq)3), bis(2-(3,5-dimethylphenyl)quinoline-C2,N')(acetylacetonate)iridium (Ir(dmpq)2(acac)), bis(2-(2,4-difluorophenyl)quinolineiridium)picolinic acid (FPQIrpic), etc.

[0682] Examples of the compound represented by formula (B-1) include the following compounds.

[0683]

[0684]

[0685]

[0686] In addition, iridium complexes described in Japanese Patent Publication No. 2006-089398, Japanese Patent Publication No. 2006-080419, Japanese Patent Publication No. 2005-298483, Japanese Patent Publication No. 2005-097263, and Japanese Patent Publication No. 2004-111379, U.S. Patent Application Publication No. 2019 / 0051845, or Advanced Materials 26: 7116 to 7121, NPG Asia Materials 13, 53 (2021), Applied Physics Letters 117, 253301 (2020), Light-Emitting Diode-An Outlook On the Empirical Features and Its Recent Technological Advances (Light-Emitting Diode-An Outlook On the Empirical Features and Its Recent Technological Advances) can be used. The platinum complex described in Advances in Photonics, Chapter 5, Nature Photonics, Vol. 16, pp. 212-218 (2022).

[0687] <Other dopant materials>

[0688] The polycyclic aromatic compound including the structural unit represented by formula (1) can be used in combination with other dopant materials. However, the other dopant materials are preferably less than 100% by mass, more preferably less than 50% by mass, further preferably less than 30% by mass, and particularly preferably less than 10% by mass in one light-emitting layer relative to the total mass of the polycyclic aromatic compound including the structural unit represented by the formula (1). As other dopant materials, known compounds can be used, and they can be selected from various materials according to the desired luminescent color. Specifically, for example, phenanthrene, anthracene, pyrene, tetracene, pentacene, perylene, naphthopyrene, dibenzopyrene, rubrene and Condensed ring derivatives such as benzoxazole derivatives, benzothiazole derivatives, benzimidazole derivatives, benzotriazole derivatives, oxazole derivatives, oxadiazole derivatives, thiazole derivatives, imidazole derivatives, thiadiazole derivatives, triazole derivatives, pyrazoline derivatives, distyryl derivatives, thiophene derivatives, tetraphenylbutadiene derivatives, cyclopentadiene derivatives, distyryl anthracene derivatives, distyryl benzene derivatives, etc. (Japanese Patent Publication No. 1-245087); bistyryl arylene derivatives (Japanese Patent Publication No. 2-247278), diazaindacene derivatives, furan derivatives, benzofuran derivatives, phenylisobenzofuran, bistrisylisobenzofuran, di(2-methylphenyl)iso isobenzofuran derivatives such as benzofuran, bis(2-trifluoromethylphenyl)isobenzofuran, and phenylisobenzofuran; coumarin derivatives such as dibenzofuran derivatives, 7-dialkylaminocoumarin derivatives, 7-piperidylcoumarin derivatives, 7-hydroxycoumarin derivatives, 7-methoxycoumarin derivatives, 7-acetoxycoumarin derivatives, 3-benzothiazolylcoumarin derivatives, 3-benzimidazolylcoumarin derivatives, and 3-benzoxazolylcoumarin derivatives; dicyanomethylenepyran derivatives, dicyanomethylenethiopyran derivatives, polymethine derivatives, cyanine derivatives, oxybenzanthracene derivatives, xanthene derivatives, rhodamine derivatives, fluorescein derivatives, pyrylium derivatives, quinolone derivatives, acridine derivatives, oxazine derivatives, and phenylene ether derivatives. oxide derivatives, quinacridone derivatives, quinazoline derivatives, pyrrolopyridine derivatives, furanopyridine derivatives, 1,2,5-thiadiazolopyrene derivatives, pyrromethene derivatives, perynone derivatives, pyrrolopyrrole derivatives, squarylium salt derivatives, violanthrone derivatives, phenazine derivatives, acridone derivatives, deazaflavin derivatives, fluorene derivatives and benzofluorene derivatives, etc.

[0689] As other dopant materials, it is also preferable to use a boron-containing polycyclic aromatic compound described in paragraphs 0097 to 0269 of International Publication No. 2015 / 102118, International Publication No. 2020 / 162600, and Japanese Patent Publication No. 2021-077890.

[0690] Examples of other dopant materials include the following compounds.

[0691]

[0692]

[0693] 2-1-6. Electron injection layer and electron transport layer of organic electroluminescent element

[0694] The electron injection layer 107 plays a role in efficiently injecting electrons migrated from the cathode 108 into the light-emitting layer 105 or the electron transport layer 106. The electron transport layer 106 plays a role in efficiently transporting electrons injected from the cathode 108 or electrons injected from the cathode 108 through the electron injection layer 107 to the light-emitting layer 105. The electron transport layer 106 and the electron injection layer 107 are respectively formed by laminating or mixing one or more electron transport / injection materials, or are formed by a mixture of electron transport / injection materials and a polymer binder.

[0695] The electron injection and transport layer is a layer responsible for injecting electrons from the cathode and then transporting electrons, preferably with high electron injection efficiency and efficient transmission of injected electrons. For this reason, it is preferably a material with large electron affinity, large electron mobility, excellent stability, and difficulty in producing impurities that become traps during manufacture and use. However, considering the transmission balance of holes and electrons, in the case of mainly playing a role of efficiently preventing holes from the anode from recombining and flowing to the cathode side, even if the electron transport capacity is not very high, it has the effect of improving luminous efficiency equally with materials with high electron transport capacity. Therefore, the electron injection and transport layer in the present embodiment may also include the function of a layer that can efficiently prevent the migration of holes.

[0696] The material (electron transport material) forming the electron transport layer 106 or the electron injection layer 107 can be arbitrarily selected from compounds conventionally used as electron transfer compounds in photoconductive materials and known compounds used for electron injection layers and electron transport layers of organic EL elements.

[0697] As a material for an electron transport layer or an electron injection layer, it is preferably containing at least one selected from the following compounds: a compound formed by an aromatic ring or heteroaromatic ring containing one or more atoms selected from carbon, hydrogen, oxygen, sulfur, silicon and phosphorus, a pyrrole derivative and its condensed ring derivative, and a metal complex with electron-accepting nitrogen. Specifically, it can be listed: condensed ring aromatic ring derivatives such as naphthalene and anthracene, styrene-based aromatic ring derivatives represented by 4,4'-bis(diphenylvinyl)biphenyl, purple ring ketone derivatives, coumarin derivatives, naphthylimide derivatives, quinone derivatives such as anthraquinone or diphenylquinone, phosphine oxide derivatives, aryl nitrile derivatives and indole derivatives. As a metal complex with electron-accepting nitrogen, for example: hydroxyl oxazole complexes such as hydroxyphenyloxazole complexes, azomethine complexes, tropolone metal complexes, flavonol metal complexes and benzoquinoline metal complexes. These materials can be used alone, but can also be mixed with different materials.

[0698] In addition, specific examples of other electron transfer compounds include pyridine derivatives, naphthalene derivatives, anthracene derivatives, phenanthroline derivatives, perinone derivatives, coumarin derivatives, naphthylimide derivatives, anthraquinone derivatives, diphenoquinone derivatives, diphenylquinone derivatives, perylene derivatives, oxadiazole derivatives (1,3-bis[(4-tert-butylphenyl)1,3,4-oxadiazolyl]phenylene, etc.), thiophene derivatives, triazole derivatives (N-naphthyl-2,5-diphenyl-1,3,4-triazole, etc.), thiadiazole derivatives, metal complexes of auxin derivatives, hydroxyquinoline metal complexes, quinoxaline derivatives, polymers of quinoxaline derivatives, benzoxazole compounds, gallium complexes, pyrazole derivatives, perfluorinated phenylene derivatives. Compounds, triazine derivatives, pyrazine derivatives, benzoquinoline derivatives (2,2'-bis(benzo[h]quinolin-2-yl)-9,9'-spirofluorene, etc.), imidazopyridine derivatives, borane derivatives, benzimidazole derivatives (tris(N-phenylbenzimidazole-2-yl)benzene, etc.), benzoxazole derivatives, benzothiazole derivatives, quinoline derivatives, oligopyridine derivatives such as terpyridine, bipyridine derivatives, terpyridine derivatives (1,3-bis(2,2':6'2"-terpyridine-4'-yl)benzene, etc.), naphthyridine derivatives (bis(1-naphthyl)-4-(1,8-naphthyridin-2-yl)phenylphosphine oxide, etc.), aldazine derivatives, carbazole derivatives, indole derivatives, phosphine oxide derivatives, bisphenylvinyl derivatives, etc.

[0699] In addition, a metal complex having electron-accepting nitrogen can be used, and examples thereof include hydroxyquinoline metal complexes, hydroxyoxazole complexes such as hydroxyphenyloxazole complexes, azomethine complexes, tropolone metal complexes, flavonol metal complexes, and benzoquinoline metal complexes.

[0700] The materials may be used alone or in combination with different materials.

[0701] Among the above materials, preferred are borane derivatives, pyridine derivatives, fluoranthene derivatives, BO derivatives, anthracene derivatives, benzofluorene derivatives, phosphine oxide derivatives, pyrimidine derivatives, aromatic nitrile derivatives, triazine derivatives, benzimidazole derivatives, phenanthroline derivatives and hydroxyquinoline metal complexes.

[0702] The electron transport layer or the electron injection layer may also contain a substance that can reduce the material forming the electron transport layer or the electron injection layer. As long as the reducing substance has a certain reducing property, various substances can be used, for example, it is preferred to use at least one selected from the following group consisting of alkali metals, alkaline earth metals, rare earth metals, alkali metal oxides, alkali metal halides, alkaline earth metal oxides, alkaline earth metal halides, rare earth metal oxides, rare earth metal halides, alkali metal organic complexes, alkaline earth metal organic complexes, and rare earth metal organic complexes.

[0703] As preferred reducing substances, alkali metals such as Na (work function is 2.36eV), K (work function is 2.28eV), Rb (work function is 2.16eV) or Cs (work function is 1.95eV), or alkaline earth metals such as Ca (work function is 2.9eV), Sr (work function is 2.0eV to 2.5eV) or Ba (work function is 2.52eV), and substances with a work function of less than 2.9eV are particularly preferred. Among them, the more preferred reducing substance is an alkali metal of K, Rb or Cs, further preferably Rb or Cs, and most preferably Cs. These alkali metals are particularly high in reducing power, and by adding a relatively small amount of these alkali metals to the material forming the electron transport layer or the electron injection layer, the luminous brightness in the organic EL element can be improved or the life span can be extended. In addition, as the reducing substance having a work function of 2.9 eV or less, a combination of two or more of the alkali metals is also preferred, and a combination containing Cs is particularly preferred, such as a combination of Cs and Na, Cs and K, Cs and Rb, or Cs and Na and K. By including Cs, the reducing ability can be efficiently exerted, and by adding it to the material forming the electron transport layer or the electron injection layer, the luminance of the light emission in the organic EL element can be improved or the life can be prolonged.

[0704] 2-1-7. Cathode of organic electroluminescent element

[0705] The cathode 108 plays a role of injecting electrons into the light-emitting layer 105 through the electron injection layer 107 and the electron transport layer 106 .

[0706] As the material forming the cathode 108, as long as it is a substance that can efficiently inject electrons into the organic layer, it is not particularly limited, but the same material as the material forming the anode 102 can be used. Among them, preferably metals such as tin, indium, calcium, aluminum, silver, copper, nickel, chromium, gold, platinum, iron, zinc, lithium, sodium, potassium, cesium and magnesium or their alloys (magnesium-silver alloy, magnesium-indium alloy, aluminum-lithium alloy such as lithium fluoride / aluminum, etc.) and the like. In order to improve the efficiency of electron injection and enhance the characteristics of the device, lithium, sodium, potassium, cesium, calcium, magnesium or alloys containing these low work function metals are effective. However, these low work function metals are usually unstable in the atmosphere. In order to improve this, it is known that there are methods such as doping a trace amount of lithium, cesium or magnesium in the organic layer and using electrodes with high stability. As other dopants, inorganic salts such as lithium fluoride, cesium fluoride, lithium oxide and cesium oxide can also be used. But it is not limited to this.

[0707] Furthermore, the following are preferred examples: for protecting the electrodes, metals such as platinum, gold, silver, copper, iron, tin, aluminum and indium, or alloys of these metals, inorganic substances such as silicon dioxide, titanium dioxide and silicon nitride, polyvinyl alcohol, vinyl chloride, hydrocarbon polymer compounds, etc. are laminated. The method for making these electrodes is not particularly limited as long as it is a method that can achieve conductivity such as resistance heating, electron beam evaporation, sputtering, ion plating and coating.

[0708] 2-1-8. Method for manufacturing organic electroluminescent element

[0709] Each layer constituting an organic EL element can be formed by making the material constituting each layer into a thin film using a method such as vapor deposition, resistance heating vapor deposition, electron beam vapor deposition, sputtering, molecular layering, printing, spin coating, casting, or coating. The film thickness of each layer formed in the above manner is not particularly limited and can be appropriately set according to the properties of the material, but is generally in the range of 2nm to 5000nm. The film thickness can generally be measured using a crystal oscillation film thickness measuring device or the like. When thin film formation is performed using the vapor deposition method, the vapor deposition conditions vary depending on the type of material, the target crystalline structure and association structure of the film, and the like. Generally speaking, the vapor deposition conditions are preferably a boat heating temperature of +50°C to +400°C, a vacuum degree of 10 -6 Pa to 10 - 3 Pa, the vapor deposition rate is 0.01 nm / sec to 50 nm / sec, the substrate temperature is -150°C to +300°C, and the film thickness is appropriately set within the range of 2 nm to 5 μm.

[0710] When a DC voltage is applied to the organic EL element obtained in the above manner, as long as the anode is applied with a + polarity and the cathode is applied with a - polarity, if a voltage of about 2V to 40V is applied, light emission can be observed from the transparent or translucent electrode side (anode or cathode, and both sides). In addition, the organic EL element also emits light when a pulse current or an alternating current is applied. In addition, the waveform of the applied alternating current can be arbitrary.

[0711] Next, as an example of a method for producing an organic EL element, a method for producing an organic EL element including anode / hole injection layer / hole transport layer / light-emitting layer including a host material and a dopant material / electron transport layer / electron injection layer / cathode is described.

[0712] <Evaporation method>

[0713] On a suitable substrate, after forming a thin film of an anode material by a vapor deposition method, a thin film of a hole injection layer and a hole transport layer is formed on the anode. A main material and a dopant material are co-evaporated thereon to form a thin film to form a light-emitting layer, an electron transport layer and an electron injection layer are formed on the light-emitting layer, and then a thin film containing a cathode material is formed by a vapor deposition method, thereby obtaining a desired organic EL element. In addition, in the production of the above-mentioned organic EL element, the production order can also be reversed, and it is produced in the order of cathode, electron injection layer, electron transport layer, light-emitting layer, hole transport layer, hole injection layer, and anode.

[0714] <Wet film forming method>

[0715] The wet film forming method is implemented by preparing a low molecular weight compound that can form each organic layer of the organic EL element as a liquid organic layer forming composition and using the composition. When there is no suitable organic solvent that dissolves such a low molecular weight compound, the organic layer forming composition can be prepared from other monomers having a solubility function or a polymer compound that is polymerized with a main chain polymer as a reactive compound that replaces the reactive substituent in the low molecular weight compound.

[0716] In general, the wet film forming method forms a coating film by going through a coating process of applying an organic layer forming composition on a substrate and a drying process of removing a solvent from the applied organic layer forming composition. When the polymer compound has a cross-linkable substituent (also referred to as a cross-linkable polymer compound), it is further cross-linked to form a polymer cross-linked body by the drying process. According to the difference in coating process, the method using a spin coater is called a spin coating method, the method using a slit coater is called a slit coating method, the method using a plate is called a gravure, an offset plate, a reverse offset plate, a flexographic printing method, the method using an inkjet printer is called an inkjet method, and the method sprayed in a mist state is called a spray method. Drying process has methods such as air drying, heating, and reduced pressure drying. Drying process can be performed only once, or multiple times using different methods or conditions. In addition, for example, calcining under reduced pressure, different methods can also be used.

[0717] The wet film forming method refers to a film forming method using a solution, for example, a part of the printing method (inkjet method), spin coating method or casting method, coating method, etc. The wet film forming method is different from the vacuum evaporation method, and does not require the use of expensive vacuum evaporation equipment, and can form a film under atmospheric pressure. In addition, the wet film forming method can be large-scale and continuous production, which helps to reduce manufacturing costs.

[0718] On the other hand, compared with the vacuum evaporation method, the wet film forming method is sometimes difficult to laminate. When using the wet film forming method to make a laminated film, it is necessary to prevent the lower layer from being dissolved by the composition of the upper layer, and use a composition with controlled solubility, crosslinking of the lower layer, and orthogonal solvents (orthogonal solvents, mutually immiscible solvents). However, even with these technologies, it is sometimes difficult to use the wet film forming method in the coating of the entire film.

[0719] Therefore, a method is generally adopted in which only a few layers are formed using a wet film forming method and the rest are formed using a vacuum evaporation method to produce an organic EL element.

[0720] For example, the following shows a process for producing an organic EL element by partially applying a wet film-forming method.

[0721] (Step 1) Anode film formation by vacuum evaporation

[0722] (Step 2) Formation of a hole injection layer-forming composition containing a hole injection layer material by a wet film-forming method (Step 3) Formation of a hole transport layer-forming composition containing a hole transport layer material by a wet film-forming method (Step 4) Formation of a light-emitting layer-forming composition containing a host material and a dopant material by a wet film-forming method (Step 5) Formation of an electron transport layer by a vacuum evaporation method

[0723] (Step 6) Formation of electron injection layer by vacuum deposition

[0724] (Step 7) Cathode film formation by vacuum evaporation

[0725] By going through the above steps, an organic EL element including anode / hole injection layer / hole transport layer / light-emitting layer including host material and dopant material / electron transport layer / electron injection layer / cathode is obtained.

[0726] Of course, for the electron transport layer and the electron injection layer, a layer-forming composition containing a material for the electron transport layer and a material for the electron injection layer, respectively, can also be used, and a film can be formed by a wet film-forming method. In this case, it is preferred to use a method that prevents the lower light-emitting layer from dissolving, or to start film formation from the cathode side in contrast to the above steps.

[0727] <Other film forming methods>

[0728] The organic layer-forming composition can be formed into a film by laser heating drawing (laser induced thermal imaging (LITI)). LITI is a method of heating and evaporating a compound attached to a substrate using a laser, and the organic layer-forming composition can be used as the material applied to the substrate.

[0729] <Optional Process>

[0730] Before and after each film forming process, appropriate treatment process, cleaning process and drying process may be appropriately added. Examples of the treatment process include exposure treatment, plasma surface treatment, ultrasonic treatment, ozone treatment, cleaning treatment using an appropriate solvent and heating treatment. In addition, a series of processes for making a bank may also be mentioned.

[0731] The levee can be made using photolithography. As the levee material that can be used for photolithography, positive resist materials and negative resist materials can be used. In addition, a printing method that can form a pattern, such as an inkjet method, gravure offset printing, reverse offset printing, screen printing, etc., can also be used. In this case, a permanent resist material can also be used.

[0732] <Organic Layer Forming Composition Used in Wet Film Formation Method>

[0733] The composition for forming an organic layer is obtained by dissolving a low molecular compound that can form each organic layer of an organic EL element or a high molecular compound that polymerizes the low molecular compound in an organic solvent. For example, the composition for forming a light-emitting layer includes at least one dopant material, i.e., a polycyclic aromatic compound (or its high molecular compound) as a first component, at least one main material as a second component, and at least one organic solvent as a third component. The first component acts as a dopant component of the light-emitting layer obtained from the composition, and the second component acts as a main component of the light-emitting layer. The third component acts as a solvent for dissolving the first component and the second component in the composition, and when applied, a smooth and uniform surface shape is imparted by the controlled evaporation rate of the third component itself.

[0734] <Organic Solvents>

[0735] The composition for forming an organic layer includes at least one organic solvent. By controlling the evaporation rate of the organic solvent during film formation, the film-forming property, the presence or absence of coating defects, surface roughness, and smoothness can be controlled and improved. In addition, when the film is formed by an inkjet method, the stability of the meniscus in the pinhole of the inkjet head can be controlled to control and improve the ejection property. In addition, by controlling the drying rate of the film and the orientation of the derivative molecules, the electrical properties, luminescent properties, efficiency, and life of an organic EL element having an organic layer obtained from the composition for forming an organic layer can be improved.

[0736] The organic solvent is removed from the coating film by a drying process such as vacuum, decompression, heating, etc. after film formation. In the case of heating, from the viewpoint of improving the coating film-forming property, it is preferably carried out below the glass transition temperature (Tg) of at least one of the solutes + 30°C. In addition, from the viewpoint of reducing the residual solvent, it is preferably heated above the glass transition temperature (Tg) of at least one of the solutes -30°C. Even if the heating temperature is lower than the boiling point of the organic solvent, the organic solvent will be fully removed due to the thin film. In addition, it is also possible to perform multiple dryings at other temperatures, or to use multiple drying methods in combination.

[0737] Specific examples of organic solvents

[0738] As the organic solvent used in the composition for forming an organic layer, alkylbenzene solvents, phenyl ether solvents, alkyl ether solvents, cyclic ketone solvents, aliphatic ketone solvents, monocyclic ketone solvents, solvents with a diester skeleton, and fluorine-containing solvents can be listed, but are not limited thereto. In addition, the solvent can be used alone or in combination.

[0739] <Optional Ingredients>

[0740] The composition for forming an organic layer may contain an optional component within a range that does not impair its properties. Examples of the optional component include a binder and a surfactant.

[0741] <Composition and Properties of Organic Layer-Forming Composition>

[0742] The content of each component in the organic layer forming composition is determined after taking into account the good solubility, storage stability and film-forming properties of each component in the organic layer forming composition, the high-quality film quality of the coating obtained from the organic layer forming composition, the good ejection properties when using the inkjet method, and the good electrical properties, luminescent properties, efficiency and life of the organic EL element having an organic layer made using the composition.

[0743] The composition for forming an organic layer can be prepared by appropriately selecting stirring, mixing, heating, cooling, dissolving, dispersing, etc. on the components by a known method. In addition, after preparation, filtration, gas removal (also called degassing), ion exchange treatment, and inert gas substitution and sealing treatment can be appropriately selected.

[0744] 2-1-9. Application examples of organic electroluminescent elements

[0745] The present invention can be applied to a display device including an organic EL element, a lighting device including an organic EL element, or the like.

[0746] A display device or lighting device including an organic EL element can be manufactured by a known method such as connecting the organic EL element according to this embodiment to a known driving device, and can be appropriately driven using known driving methods such as DC driving, pulse driving, and AC driving.

[0747] As display devices, for example, panel displays such as color flat panel displays, flexible displays such as flexible color organic electroluminescent (EL) displays, etc. (for example, refer to Japanese Patent Publication No. 10-335066, Japanese Patent Publication No. 2003-321546, Japanese Patent Publication No. 2004-281086, etc.). In addition, as display modes of displays, for example, matrix and segment modes can be listed. In addition, matrix display and segment display can coexist in the same panel.

[0748] In a matrix, pixels for display are arranged in a two-dimensional manner such as a grid or mosaic, and text or images are displayed by a collection of pixels. The shape or size of a pixel is determined by the purpose. For example, in the display of images and texts in computers, monitors, and televisions, quadrilateral pixels with a side of less than 300 μm are generally used, and in the case of large displays such as display panels, pixels with a side of mm are used. In the case of monochrome display, pixels of the same color can be arranged, but in the case of color display, red, green, and blue pixels are displayed side by side. In this case, typical ones are delta type and stripe type. In addition, as a driving method of the matrix, it can be any one of a line sequential (sequential) driving method or an active matrix. Although the line sequential drive has the advantage of a simple structure, considering the operating characteristics, the active matrix method is sometimes excellent, so it is necessary to distinguish and use the driving method according to the purpose.

[0749] In the segmented mode (type), a pattern is formed to display predetermined information and a predetermined area is illuminated. For example, time or temperature display on a digital watch or thermometer, operation status display of an audio device or an electronic cooking machine, and panel display of a car can be cited.

[0750] As lighting devices, for example, lighting devices such as indoor lighting, backlight sources of liquid crystal display devices, etc. can be cited (for example, refer to Japanese Patent Publication No. 2003-257621, Japanese Patent Publication No. 2003-277741, Japanese Patent Publication No. 2004-119211, etc.). Backlight sources are mainly used to improve the visibility of display devices that are not self-luminous, and are used for liquid crystal display devices, clocks, audio devices, car panels, display boards and logos. In particular, as a backlight source for computer use in which thinning is a problem among liquid crystal display devices, considering that the previous methods include fluorescent lamps or light guide plates, it is difficult to achieve thinning, and the backlight source using the light-emitting element of this embodiment has the characteristics of being thin and lightweight.

[0751] 2-2. Other organic devices

[0752] The polycyclic aromatic compound according to the present invention can be used to produce organic field effect transistors or organic thin film solar cells in addition to the organic electroluminescent element.

[0753] An organic field effect transistor is a transistor that controls current by an electric field generated by voltage input. In addition to a source electrode and a drain electrode, a gate electrode is also provided. If a voltage is applied to the gate electrode, an electric field is generated, and the flow of electrons (or holes) flowing between the source electrode and the drain electrode can be blocked at will to control the current. Compared with simple transistors (bipolar transistors), field effect transistors are easy to miniaturize, so they are often used as components of integrated circuits, etc.

[0754] The structure of the organic field effect transistor is generally to provide a source electrode and a drain electrode in contact with an organic semiconductor active layer formed using the polycyclic aromatic compound according to the present invention, and further to provide a gate electrode via an insulating layer (dielectric layer) in contact with the organic semiconductor active layer. Examples of the element structure include the following structures.

[0755] (1) Substrate / gate electrode / insulator layer / source electrode / drain electrode / organic semiconductor active layer

[0756] (2) Substrate / gate electrode / insulator layer / organic semiconductor active layer / source electrode / drain electrode

[0757] (3) Substrate / organic semiconductor active layer / source electrode / drain electrode / insulator layer / gate electrode

[0758] (4) Substrate / source electrode / drain electrode / organic semiconductor active layer / insulator layer / gate electrode

[0759] The organic field effect transistor constructed as described above can be used as a pixel driving switch element of an active matrix driven liquid crystal display panel or an organic light emitting element display, etc.

[0760] Organic thin film solar cells have a structure in which an anode, a hole transport layer, a photoelectric conversion layer, an electron transport layer, and a cathode are stacked on a transparent substrate such as glass, such as indium tin oxide (Indium Tin Oxide, ITO). The photoelectric conversion layer has a p-type semiconductor layer on the anode side and an n-type semiconductor layer on the cathode side. The polycyclic aromatic compound according to the present invention can be used as a material for a hole transport layer, a p-type semiconductor layer, an n-type semiconductor layer, and an electron transport layer according to its physical properties. In an organic thin film solar cell, the polycyclic aromatic compound according to the present invention can act as a hole transport material or an electron transport material. In addition to the above, the organic thin film solar cell may also appropriately include a hole blocking layer, an electron blocking layer, an electron injection layer, a hole injection layer, a smoothing layer, and the like. In an organic thin film solar cell, known materials used in organic thin film solar cells can be appropriately selected and used in combination.

[0761] 3. Wavelength conversion materials

[0762] The polycyclic aromatic compound of the present invention can be used as a wavelength conversion material. Currently, the application of multi-colorization technology using color conversion to liquid crystal display screens or organic EL displays, lighting, etc. is being actively studied. Color conversion refers to converting the wavelength of light emitted from a light source into light with a longer wavelength, for example, it is manifested as converting ultraviolet light or blue light into green light or red light. By thinning the wavelength conversion material having such a color conversion function, for example, in combination with a blue light source, the three primary colors of blue, green, and red, that is, white light, can be extracted from the blue light source. A white light source combining the above-mentioned blue light source with a wavelength conversion film having a color conversion function is used as a light source unit, and the liquid crystal drive part is combined with a color filter, so that a full-color display can be made. In addition, if there is no liquid crystal drive part, it can be directly used as a white light source, for example, it can be applied as a white light source for a light-emitting diode (LED) lighting lamp. In addition, by using a blue organic EL element as a light source, combined with a wavelength conversion film that converts blue light into green light and red light, a full-color organic EL display without using a metal mask can be made. Furthermore, by using blue micro-LEDs as light sources in combination with a wavelength conversion film that converts blue light into green and red light, a low-cost full-color micro-LED display can be produced.

[0763] The polycyclic aromatic compound of the present invention can be used as the wavelength conversion material. By using a wavelength conversion material including the polycyclic aromatic compound of the present invention, light from a light source or a light-emitting element that generates ultraviolet light or blue light of a shorter wavelength can be converted into blue light or green light with high color purity suitable for use in a display device (a display device or a liquid crystal display device using an organic EL element). By appropriately selecting the substituent of the polycyclic aromatic compound of the present invention, the binder resin used as the wavelength conversion composition to be described below, etc., the color of the conversion can be adjusted. The wavelength conversion material can be modulated as a wavelength conversion composition containing the polycyclic aromatic compound of the present invention. In addition, the wavelength conversion composition can be used to form a wavelength conversion film.

[0764] The wavelength conversion composition may further include a binder resin, other additives, and a solvent in addition to the polycyclic aromatic compound of the present invention. As the binder resin, for example, the contents described in paragraphs 0173 to 0176 of International Publication No. 2016 / 190283 may be used. As other additives, the compounds described in paragraphs 0177 to 0181 of International Publication No. 2016 / 190283 may be used. As the solvent, reference may be made to the description of the solvent contained in the composition for forming the light-emitting layer.

[0765] The wavelength conversion film includes a wavelength conversion layer formed by curing the wavelength conversion composition. As a method for making a wavelength conversion layer from a wavelength conversion composition, reference can be made to a known film formation method. The wavelength conversion film may include only a wavelength conversion layer formed by a composition comprising a polycyclic aromatic compound of the present invention, or may include other wavelength conversion layers (e.g., a wavelength conversion layer that converts blue light into green light or red light, a wavelength conversion layer that converts blue light or green light into red light). The wavelength conversion film may also include a barrier layer for preventing degradation caused by oxygen, moisture or heat of the substrate layer or the color conversion layer.

[0766] Example

[0767] Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to the examples.

[0768] <Synthesis example>

[0769] Synthesis Example (1): Synthesis of Compound (1-1)

[0770]

[0771] Under nitrogen atmosphere, at -30°C, add 1.6M tert-butyllithium pentane solution (1.6ml) to a flask containing compound (S-1-1) (1.5g) and tert-butylbenzene (7.0ml). After the addition is completed, heat to 60°C, stir for 2h, and then remove components with a lower boiling point than tert-butylbenzene by distillation under reduced pressure. Cool to -30°C, add boron tribromide (0.63g), warm to room temperature and stir for 0.5h. Then, cool to 0°C again, add N,N-diisopropylethylamine (0.43ml), stir at room temperature until the fever subsides, then heat to 120°C and heat and stir for 3 hours. The reaction solution is cooled to room temperature, and an aqueous sodium acetate solution cooled in an ice bath is added, and then heptane is added for liquid separation. Then, after purification with a silica gel short-pass column (eluent: toluene), the solvent was distilled off under reduced pressure, and the obtained solid was dissolved in toluene and reprecipitated by adding heptane to obtain compound (1-1) (0.44 g).

[0772] According to the method of Synthesis Example (1), compounds (1-2) to (1-20) and compounds (Ref-1-1) to (Ref-1-6) were synthesized. Compounds (Ref-1-1) to (Ref-1-6) are compounds described in the specifications of Science Advances. 8, eabq1641 (2022), Korean Patent Publication No. 10-2022-0069866, International Publication No. 2017 / 188111, Korean Patent Publication No. 10-2020-0011383, and U.S. Patent No. 2021 / 0143331.

[0773]

[0774] The formation of the target substance was confirmed by matrix-assisted laser desorption ionization-time of flight-mass spectrometry (MALDI-TOF-MS).

[0775] [Table 1]

[0776]

[0777]

[0778] <Fabrication and Evaluation of Evaporation-Type Organic EL Devices>

[0779] Each organic EL device of TTF, TADF, TAF, and PSF was fabricated using each of the synthesized compounds of the present invention and comparative compounds.

[0780] <TTF Structure: Examples 1-1-1 to 1-1-20 and Comparative Examples 1-1-1 to 1-1-6>

[0781] ITO (120 nm) / HI (40 nm) / HAT-CN (5 nm) / HT-1 (45 nm) / HT-2 (10 nm) / BH: Each compound described in Table 2 (97:3) (25 nm) / ET-1 (5 nm) / ET-2: Liq (1:1) (25 nm) / LiF (1 nm) / Al (100 nm)

[0782] The chemical structures of the compounds used to fabricate the devices are shown below.

[0783]

[0784] ITO formed to a thickness of 180 nm was polished to 120 nm by sputtering, and then a glass substrate (manufactured by OPTO SCIENCE Co., Ltd.) with dimensions of 26 mm × 28 mm × 0.7 mm was used as the transparent support substrate. The transparent support substrate was fixed to the substrate holder of a commercially available evaporation apparatus (manufactured by Showa Vacuum Co., Ltd.), and molybdenum evaporation boats containing HI, HAT-CN, HT-1, HT-2, BH, each compound described in Table 2, ET-1, and ET-2, and aluminum nitride evaporation boats containing Liq, LiF, and aluminum were installed.

[0785] The following layers are successively formed on the ITO film of the transparent support substrate. The vacuum chamber is evacuated to 5×10 -4 Pa. First, HI is heated and vapor-deposited so that the film thickness reaches 40 nm. Then, HAT-CN is heated and vapor-deposited so that the film thickness reaches 5 nm. Then, HT-1 is heated and vapor-deposited so that the film thickness reaches 45 nm. Then, HT-2 is heated and vapor-deposited so that the film thickness reaches 10 nm, forming a hole layer including four layers. Next, BH and each compound described in Table 2 are heated simultaneously and vapor-deposited so that the film thickness reaches 25 nm, forming a light-emitting layer. The vapor-deposition rate is adjusted so that the mass ratio of BH to each compound described in Table 2 reaches approximately 97:3. And, ET-1 is heated and vapor-deposited so that the film thickness reaches 5 nm. Then, ET-2 and Liq are heated simultaneously and vapor-deposited so that the film thickness reaches 25 nm, forming an electron layer including two layers. The vapor-deposition rate is adjusted so that the mass ratio of ET-2 to Liq reaches approximately 50:50. The vapor-deposition rate of each layer is 0.01 nm / second to 1 nm / second. After that, LiF is heated and vapor-deposited at a vapor-deposition rate of 0.01 nm / second to 0.1 nm / second so that the film thickness reaches 1 nm. Then, aluminum is heated and vapor-deposited so that the film thickness reaches 100 nm, forming a cathode, thereby obtaining an organic EL element.

[0786] <TADF Configuration: Examples 2-1-1 to 2-1-20 and Comparative Examples 2-1-1 to 2-1-6>

[0787] ITO(50 nm) / HAT-CN(10 nm) / HT-1(60 nm) / SiCzCz(5 nm) / SiCzCz:SiTrzCz2:Compound described in Table 2(60:39:1)(35 nm) / mSiTrz(5 nm) / mSiTrz:Liq(1:1)(30 nm) / LiF(1 nm) / Al(100 nm)

[0788] The ITO film formed to a thickness of 200 nm is polished to 50 nm by sputtering, and then a glass substrate (manufactured by Opto Science Co., Ltd.) of 26 mm × 28 mm × 0.7 mm is used as the transparent support substrate. The transparent support substrate is fixed to the substrate holder of a commercially available vapor deposition apparatus (manufactured by Showa Vacuum Co., Ltd.), and molybdenum vapor deposition boats respectively containing HAT-CN, HT-1, SiCzCz, SiTrzCz2, each compound described in Table 2, mSiTrz, and Liq, and tungsten nitride vapor deposition boats respectively containing LiF and aluminum are installed.

[0789] The following layers are successively formed on the ITO film of the transparent substrate. The vacuum chamber is evacuated to 5×10 -4Pa, first, heat HAT-CN and perform evaporation deposition in such a way that the film thickness reaches 10 nm to form a hole injection layer. Next, heat HT-1 and perform evaporation deposition in such a way that the film thickness reaches 60 nm to form hole transport layer 1. Then, heat SiCzCz and perform evaporation deposition in such a way that the film thickness reaches 5 nm to form hole transport layer 2. Then, heat SiCzCz, SiTrzCz2, and each compound described in Table 2 simultaneously and perform evaporation deposition in such a way that the film thickness reaches 35 nm to form a light-emitting layer. Adjust the evaporation deposition rate so that the mass ratio of SiCzCz, SiTrzCz2, and each compound described in Table 2 is approximately 60:39:1. Next, heat mSiTrz and perform evaporation deposition in such a way that the film thickness reaches 5 nm to form electron transport layer 1. Then, heat mSiTrz and Liq simultaneously and perform evaporation deposition in such a way that the film thickness reaches 30 nm to form electron transport layer 2. Adjust the evaporation deposition rate so that the mass ratio of SiTrz and Liq is approximately 1:1. The evaporation deposition rate of each layer is from 0.01 nm / second to 1 nm / second. After that, heat LiF and perform evaporation deposition at an evaporation deposition rate of from 0.01 nm / second to 0.1 nm / second in such a way that the film thickness reaches 1 nm. Then, heat aluminum and perform evaporation deposition in such a way that the film thickness reaches 100 nm to form a cathode, thereby obtaining an organic EL element. At this time, the evaporation deposition rate of aluminum is adjusted to be from 1 nm / second to 10 nm / second. Additionally, SiCzCz in the light-emitting layer corresponds to a hole-transporting host material, and SiTrzCz2 corresponds to an electron-transporting host material.

[0790] <TAF composition: Examples 3-1-1 to 3-1-20, Comparative Examples 3-1-1 to 3-1-6>

[0791] ITO(50 nm) / HAT-CN(10 nm) / HT-1(60 nm) / SiCzCz(5 nm) / SiCzCz:SiTrzCz2:TADF-1: each compound described in Table 2(60:26:13:1)(35 nm) / mSiTrz(5 nm) / mSiTrz:Liq(1:1)(30 nm) / LiF(1 nm) / Al(100 nm)

[0792] Except for the light-emitting layer, it is fabricated in the same manner as the TADF composition. In the light-emitting layer, heat SiCzCz, SiTrzCz2, (TADF-1), and each compound described in Table 2 simultaneously and perform evaporation deposition in such a way that the film thickness reaches 35 nm. Adjust the evaporation deposition rate so that the mass ratio of SiCz, SiTrzCz2, (TADF-1), and the compound described in Table 2 is approximately 60:26:13:1.

[0793] <PSF Configuration: Examples 4-1-1 to 4-1-20, Comparative Examples 4-1-1 to 4-1-6>

[0794] ITO (50 nm) / HAT-CN (10 nm) / HT-1 (60 nm) / SiCzCz (5 nm) / SiCzCz:SiTrzCz2:PtON-TBBI: Each compound described in Table 2 (60:26:13:1) (35 nm) / mSiTrz (5 nm) / mSiTrz:Liq (1:1) (30 nm) / LiF (1 nm) / Al (100 nm)

[0795] The device was fabricated in the same manner with (TADF-1) formed by replacing the TAF with PTON-TBBI.

[0796] The chemical structures of the compounds used in the fabrication of each device are shown below.

[0797]

[0798] [Evaluation]

[0799] As evaluation items, it includes driving voltage (V), emission wavelength (nm), Commission Internationale de l’Eclairage (CIE) chromaticity (x, y), external quantum efficiency (%), maximum wavelength (nm) and full width at half maximum (nm) of the emission spectrum, etc. These evaluation items can use, for example, the value when emitting light at 1000 cd / m 2 Value during light emission.

[0800] The quantum efficiency of the light-emitting device includes internal quantum efficiency and external quantum efficiency. The internal quantum efficiency represents the ratio of the external energy converted into pure photons by injecting electrons (or holes) into the light-emitting layer of the light-emitting device. On the other hand, the external quantum efficiency is calculated based on the amount of photons emitted to the outside of the light-emitting device, and since a part of the photons generated in the light-emitting layer is absorbed or continuously reflected inside the light-emitting device and not released to the outside of the light-emitting device, the external quantum efficiency is lower than the internal quantum efficiency.

[0801] The measurement methods of the spectral radiance (emission spectrum) and the external quantum efficiency are shown below. Using the voltage / current generator R6144 manufactured by Advantest Corporation, a voltage was applied to make the device emit light so that the brightness of the device was 1000 cd / m 2. Using the SR-3AR spectroradiometer manufactured by TOPCON, the spectral radiance in the visible light region is measured in the vertical direction to the light-emitting surface. Assuming that the light-emitting surface is a completely diffuse surface, the measured spectral radiance of each wavelength component is divided by the wavelength energy, and the value multiplied by π is the number of photons at each wavelength. Then, the number of photons is accumulated in the observed full wavelength region as the number of electric photons emitted from the element. The applied current value is divided by the value of the small charge as the number of carriers injected into the element, and the number of electric photons released from the element is divided by the number of carriers injected into the element. The external quantum efficiency is the value obtained by dividing the number of electric photons released from the element by the number of carriers injected into the element. In addition, the half-width of the luminescence spectrum is centered on the maximum luminescence wavelength, and the width between the upper and lower wavelengths where the intensity is 50% is calculated.

[0802] The ITO electrode was used as the anode and the LiF / aluminum electrode was used as the cathode. A DC voltage was applied and the 1000 cd / m 2 Characteristics during light emission. In addition, for the TTF component, the time (lifetime) to maintain a brightness of 95% or more of the initial brightness was measured, and for the TADF, TAF, and PSF components, the time (lifetime) to maintain a brightness of 50% or more of the initial brightness was measured. In addition, the light emission peaks of the components were all within the range of 450nm to 470nm.

[0803] The results are shown in Table 2.

[0804] [Table 2]

[0805]

[0806]

[0807]

[0808]

[0809] The obtained results show that the device of the example is compared with the device of the comparative example using a compound having a skeleton corresponding to the compound of the example, and that the device of the example has high efficiency and long life.

Claims

1. A polycyclic aromatic compound having a structure including one or more structural units represented by the following formula (1): In formula (1), Ring A, Ring B and Ring C are each independently a substituted or unsubstituted aryl ring, or a substituted or unsubstituted heteroaryl ring, At least one selected from the group consisting of Ring A, Ring B and Ring C has at least one ring having the formula (E ABC ) as a substituent or an aromatic ring having at least ABC ) as a substituent of a heteroaryl ring, J are each independently a group represented by formula (1Ar) or formula (2Ar), and at least one J is a group represented by formula (1Ar), In the formula (E ABC )middle, * indicates the bonding position to the aryl ring or heteroaryl ring, The P ring and the Q ring are each independently a substituted or unsubstituted aryl ring, or a substituted or unsubstituted heteroaryl ring, In formula (1Ar) and formula (2Ar), # indicates the bonding position with nitrogen, The D ring and the E ring are each independently a substituted or unsubstituted aryl ring, or a substituted or unsubstituted heteroaryl ring, In formula (1Ar), G are the same or different and are hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted arylthio, substituted or unsubstituted heteroarylthio, substituted or unsubstituted aryloxy, substituted or unsubstituted heteroaryloxy, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, or substituted or unsubstituted silyl, at least one G is substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted arylthio, substituted or unsubstituted heteroarylthio, substituted or unsubstituted aryloxy, substituted or unsubstituted heteroaryloxy, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, or substituted or unsubstituted silyl, Substituents substituted at adjacent atoms in the aryl ring and heteroaryl ring of the structure can be bonded to each other to form a ring, In the structure, at least one of the aryl ring and the heteroaryl ring can be condensed into at least one cycloalkane, the cycloalkane can have a substituent, and at least one -CH2- in the cycloalkane can be substituted by -O-, At least one hydrogen in the structure can be replaced by a cyano group or a halogen, At least one hydrogen in the structure can be replaced by deuterium, and at least one nitrogen can be replaced by 15 nitrogen( 15 N) substituted, at least one sulfur can be 33 sulfur( 33 S), 34 sulfur( 34 S) or 36 sulfur( 36 S) substitution, at least one oxygen can be 17 oxygen( 17 O) or 18 oxygen( 18 O) substitution, at least one carbon can be 13 carbon( 13 C) substituted, and at least one boron can be 11 boron( 11 B) Replacement.

2. The polycyclic aromatic compound according to claim 1, wherein Ring A, Ring B, Ring C, Ring D, Ring E, Ring P and Ring Q are each independently a substituted or unsubstituted aryl ring having 6 to 16 carbon atoms, or a substituted or unsubstituted heteroaryl ring having 2 to 15 carbon atoms.

3. The polycyclic aromatic compound according to claim 2, wherein Ring A, Ring B, Ring C, Ring D and Ring E are each independently a substituted or unsubstituted aryl ring, or a substituted or unsubstituted heteroaryl ring, The aryl ring is selected from the group consisting of a benzene ring, a biphenyl ring, an indene ring, a naphthalene ring, a fluorene ring, an anthracene ring and a phenanthrene ring, The heteroaryl ring is selected from the group consisting of a benzofuran ring, a benzothiophene ring, an indole ring, a dibenzofuran ring, a dibenzothiophene ring, a carbazole ring, a naphthofuran ring, a naphthothiophene ring, a benzoindole ring, a benzoselenophene ring, a dibenzoselenophene ring, a silanol ring and a silanol ring.

4. The polycyclic aromatic compound according to claim 1, wherein Formula (E ABC ) is given by the following formula (E ABC -1), formula (E ABC -2), formula (E ABC -3), formula (E ABC -4) or formula (E ABC -5) means: In the formula (E ABC -1), formula (E ABC -2), formula (E ABC -3), formula (E ABC -4) and formula (E ABC -5), Z E are independently -C(-R ZE )=or-N=,R ZE is hydrogen, halogen, cyano, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl, Z X are independently -C(-R ZX )=or-N=,R ZX is hydrogen, halogen, cyano, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl, Y 1 >NR NY 、>C(-R CY )2、>O、>Si(-R IY 2. PR PY 、>P(=O)R POY ,>S,>SO,>SO2 or>Se, R NY , R CY , R IY , R PY and R POY are each independently hydrogen, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl, and both R CY Can bond to each other to form a ring, two R IY Can bond to each other to form a ring.

5. The polycyclic aromatic compound according to claim 1, wherein Formula (1) is represented by the following formula (1X1): In formula (1X1), J is the same as J in formula (1), R a is hydrogen or unsubstituted alkyl, R b The same or different, and at least one R b Formula (E ABC ).

6. The polycyclic aromatic compound according to claim 5, wherein R b are independently of the formula (E ABC -1), formula (E ABC -2), formula (E ABC -3), formula (E ABC -4) or formula (E ABC -5).

7. The polycyclic aromatic compound according to claim 1, wherein J is independently a group represented by the following formula (1Ar-1) or formula (2Ar-1): In formula (1Ar-1) and formula (2Ar-1), R e are each independently hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted aryl, or substituted or unsubstituted silyl, R d are each independently hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, or substituted or unsubstituted aryl, R dd is hydrogen, or substituted or unsubstituted aryl, In formula (1Ar-1), G's are the same or different and are hydrogen, unsubstituted alkyl, haloalkyl, unsubstituted cycloalkyl, unsubstituted aryl, or unsubstituted heteroaryl, and at least one G is unsubstituted alkyl, haloalkyl, unsubstituted cycloalkyl, unsubstituted aryl, or unsubstituted heteroaryl.

8. The polycyclic aromatic compound according to claim 1, wherein J's are each independently a group represented by the formula (1Ar).

9. The polycyclic aromatic compound according to claim 1, wherein It can be expressed by any of the following formulas: 10 . An organic electroluminescent element comprising a pair of electrodes consisting of a positive electrode and a negative electrode and an organic layer arranged between the pair of electrodes, wherein the organic layer contains the polycyclic aromatic compound according to claim 1 .

11. The organic electroluminescent element according to claim 10, wherein: The organic layer is a light-emitting layer.

12. The organic electroluminescent element according to claim 11, wherein The light emitting layer includes at least one selected from the group consisting of an auxiliary dopant and a phosphorescent material.

13. A display device comprising the organic electroluminescent element according to claim 10.

14. A lighting device comprising the organic electroluminescent element according to claim 10.

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