Compound, material for organic electroluminescent device, and organic electroluminescent device

Abstract

Disclosed are a compound, a material for an organic electroluminescent device, and an organic electroluminescent device. The compound includes a polycyclic group structure represented by Formula 2 linked to at least one of ring Ar1 or ring Ar2 of the structure represented by Formula 1, and at least one, but not more than four, group structures each represented by Formula 3 linked to at least one of ring Ar5 or ring Ar6 of the polycyclic group structure represented by Formula 2. Formulae 1, 2, and 3 are described herein. # imgabs 0 # formula 3 # imgabs 1 #

Description

[0001] Cross-reference to related applications

[0002] This application claims priority to and the benefit of Korean Patent Application No. 10-2024-0145153, filed on Oct. 22, 2024, with the Korean Intellectual Property Office, and Japanese Patent Application No. 2024-009321, filed on Jan. 25, 2024, with the Japanese Patent Office, the entire disclosures of which are incorporated herein by reference in their entirety. Technical field

[0003] The present disclosure relates to compounds, materials for use in organic electroluminescent (EL) devices, and organic electroluminescent devices. Background art

[0004] Organic electroluminescent (EL) devices have been used as displays in smartphones and other consumer-oriented display devices, etc. Accordingly, there have been continuous efforts to improve display performance and achieve high color purity through the cavity effect of the top-emission method. However, although the cavity effect can achieve an improvement in color purity, the luminous efficiency may decrease.

[0005] Currently, fluorescent materials and phosphorescent materials are used as light-emitting materials in most organic EL devices to achieve the three necessary pixel colors, namely, red, green, and blue. Among such light-emitting materials, there has been continuous development in improving the luminous efficiency, device lifetime, color purity, etc. of blue light-emitting materials. One way to improve the luminous efficiency of top-emission type blue organic EL devices may include using a light-emitting dopant material that imparts narrow full width at half maximum (FWHM) and high efficiency characteristics to the organic EL device.

[0006] Recently, it has been reported that luminescent materials including a boron atom as a ring atom in a polycyclic ring system, such as Compound a and Compound b (below), exhibit blue luminescence in an organic EL device and exhibit a narrow FWHM and high luminescence efficiency. See, for example, Non-Patent Document 1: Takuji Hatakeyama et al., “Ultrapure Blue Thermally Activated Delayed Fluorescence Molecules: Efficient HOMO-LUMO Separation by the Multiple Resonance Effect”, Advanced Materials 2016, 28, 2777-2781, and Non-Patent Document 2: Yasuhiro Kondo et al., “Narrowband deep-blue organic light-emitting diode featuring an organoboron-based emitter”, Nature Photonics 2019, 13, 678-682.

[0007] Summary of the Invention

[0008] In organic electroluminescent (EL) devices, red, green, and blue (R, G, and B) each require luminescent materials with high color purity to cover a wide color gamut. However, for blue luminescent materials, it can be difficult to achieve acceptable luminescence with high color purity. In addition, the materials described in Non-Patent Documents 1 and 2 have a wide emission spectrum and insufficient color purity.

[0009] Therefore, we describe herein new blue luminescent materials that have both a narrow emission spectrum and high color purity and, in addition, exhibit an improvement in the luminescence efficiency and / or lifetime of an organic EL device.

[0010] Provided is a compound comprising: a polycyclic group structure represented by Formula 2 connected to at least one of a ring Ar having a structure represented by Formula 1 1 or a ring Ar 2 ; and at least one group structure represented by Formula 3, but not more than four group structures, each connected to at least one of a ring Ar of the polycyclic group structure represented by Formula 2 5 or a ring Ar 6 。

[0011]

[0012] In Formulas 1, 2, and 3,

[0013] Ar 1 to Ar 8 may each independently be a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 30 ring-forming atoms, or a substituted or unsubstituted heteroaromatic ring having 5 to 30 ring-forming atoms,

[0014] In Formula 1, Z may be C or Si,

[0015] In Formula 2, X may be -O-, -S-, -NR 21 -, or -CR 22 R 23 -, where R 21 、R 22 and R 23 may each independently be hydrogen, deuterium, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group,

[0016] wherein, if X is -NR 21 -, then R 21 may be bonded to the ring-forming atoms of Ar 7 ;

[0017] In Formula 2, the binding site *1 may be bonded to the adjacent ring-forming atoms of Ar 1 in the structure represented by Formula 1, or the binding site *1 may be bonded to the adjacent ring-forming atoms of Ar 2 in the structure represented by Formula 1 to form a six-membered ring, and

[0018] In Formula 3, Y may be -O-, -S-, or -NR 31 -;

[0019] where R 31 may be hydrogen, deuterium, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group, and

[0020] the binding site *2 may be bonded to the adjacent ring-forming atoms of Ar 5 in the polycyclic group structure represented by Formula 2, or the binding site *2 may be bonded to the adjacent ring-forming atoms of Ar 6 in the polycyclic group structure represented by Formula 2 to form a five-membered ring.

[0021] The compound may include a group structure represented by Formula 6 connected to the ring Ar 1 or the ring Ar 2 in the structure represented by the above Formula 1:

[0022]

[0023] wherein, in Formula 6,

[0024] R61 is deuterium, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group,

[0025] m is 0 or 1,

[0026] Ar 6 and Ar 7 X and the binding site *1 are each as described in Formula 2,

[0027] Ar 8 as described in Formula 3, and

[0028] Ar 9 as described in Formula 5 described herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The above and other aspects, features, and advantages of some embodiments of the present disclosure will become more apparent from the following description taken in conjunction with the accompanying drawings, in which:

[0030] Figure 1 is a schematic cross-sectional view showing an organic electroluminescent (EL) device according to one embodiment;

[0031] Figure 2 is a schematic cross-sectional view showing an organic EL device according to another embodiment;

[0032] Figure 3 is a schematic cross-sectional view showing an organic EL device according to another embodiment; and

[0033] Figure 4 is an explanatory diagram qualitatively showing energy states and energy levels. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0034] Embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings, where like reference numerals refer to like elements throughout the specification. In this regard, the present embodiments may have different forms and should not be construed as limited to the description set forth herein. Therefore, the embodiments are described below only by way of example with reference to the accompanying drawings. Additionally, unless otherwise stated, operations and measurements of physical properties are carried out at room temperature (about 20 °C to about 25 °C) and a relative humidity of about 40% RH to about 50% RH.

[0035] It will be understood that when an element is referred to as being "on" another element, it can be directly on the other element or there can be intervening elements therebetween. In contrast, when an element is referred to as being "directly on" another element, there are no intervening elements.

[0036] The terms used in this specification are for the purpose of describing particular embodiments only and are not intended to be limiting. As used herein, the singular forms "a", "an", and "the" are intended to include the plural forms, including "at least one", unless the context clearly dictates otherwise. Thus, a reference to an element in the claims followed by a reference to "the" element includes one element as well as a plurality of elements.

[0037] "At least one" shall not be construed as limiting "one". "Or" means "and / or". As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0038] It will be further understood that the terms "comprising" or "including", when used in this specification, indicate the presence of the stated features, regions, wholes, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more additional features, regions, wholes, steps, operations, elements, components, and / or their groups.

[0039] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning consistent with their meaning in the context of this disclosure and the relevant art, and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0040] One aspect of the present disclosure provides a compound, which comprises: a polycyclic group structure represented by Formula 2 connected to at least one of Ring Ar of the structure represented by Formula 1 1 or Ring Ar 2 , and

[0041] at least one group structure represented by Formula 3, but not more than four group structures, each connected to at least one of Ring Ar of the polycyclic group structure represented by Formula 2 5 or Ring Ar 6 . For example, the compound may have the following structure: wherein one group structure represented by Formula 3 is added (bonded or connected) to Ring Ar in the polycyclic group structure represented by Formula 2 5 and / or Ring Ar 6 .

[0042]

[0043] In Formulas 1, 2, and 3,

[0044] Ar 1 to Ar 8Each may independently be a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 30 ring-forming atoms, or a substituted or unsubstituted heteroaromatic ring having 5 to 30 ring-forming atoms.

[0045] In Formula 1, Z may be C or Si.

[0046] In Formula 2, X may be -O-, -S-, -NR 21 -, or -CR 22 R 23 -, where R 21 、R 22 and R 23 may each independently be hydrogen, deuterium, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group, where, if X is -NR 21 -, then R 21 may be bonded to the ring-forming atoms of Ar 7 .

[0047] In Formula 2, the binding site *1 may be bonded to adjacent ring-forming atoms of Ar 1 in the structure represented by Formula 1, or the binding site *1 may be bonded to adjacent ring-forming atoms of Ar 2 in the structure represented by Formula 1, and

[0048] In Formula 3, Y may be -O-, -S-, or -NR 31 -, where R 31 may be hydrogen, deuterium, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group, and

[0049] the binding site *2 may be bonded to adjacent ring-forming atoms of Ar 5 in the polycyclic group structure represented by Formula 2, or the binding site *2 may be bonded to adjacent ring-forming atoms of Ar 6 in the polycyclic group structure represented by Formula 2.

[0050] In an embodiment, in Formula 1, Ar 1 to Ar 4 may each independently be selected from:

[0051] Each unsubstituted benzene ring, cyclopentadiene ring, indene ring, naphthalene ring, anthracene ring, azulene ring, heptalene ring, acenaphthene ring, phenalene ring, fluorene ring, phenanthrene ring, biphenyl ring, terphenyl ring, benzo[9,10]phenanthrene ring, pyrene ring, ring, picene ring, perylene ring, pentaphene ring, pentacene ring, benzo[a]anthracene ring, hexaphene ring, hexacene ring, rubicene ring, trinaphthylene ring, heptaphene ring, or picene ring; and

[0052] A benzene ring, a cyclopentadiene ring, an indene ring, a naphthalene ring, an anthracene ring, an azulene ring, a heptalene ring, an acenaphthene ring, a phenalene ring, a fluorene ring, a phenanthrene ring, a biphenyl ring, a terphenyl ring, a benzo[9,10]phenanthrene ring, a pyrene ring, each substituted as follows: a perylene ring, a picene ring, a pentaphene ring, a pentacene ring, a benzo[a]anthracene ring, a hexaphene ring, a hexacene ring, a rubicene ring, a terrylene ring, a coronene ring, a heptaphene ring, or a picene ring: a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryloxy group, a substituted or unsubstituted heteroaryloxy group, a substituted or unsubstituted diarylamino group, a substituted or unsubstituted diheteroarylamino group, a substituted or unsubstituted arylheteroarylamino group, or a combination thereof.

[0053] For example, in Formula 1, Ar 1 to Ar 4 may each independently be selected from: a benzene ring; and a benzene ring substituted as follows: a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryloxy group, a substituted or unsubstituted heteroaryloxy group, a substituted or unsubstituted diarylamino group, a substituted or unsubstituted diheteroarylamino group, a substituted or unsubstituted arylheteroarylamino group, or a combination thereof. In this regard, the substituents of the substituted alkyl group, the substituted aryl group, the substituted heteroaryl group, the substituted alkoxy group, the substituted aryloxy group, the substituted heteroaryloxy group, the substituted diarylamino group, the substituted diheteroarylamino group, or the substituted arylheteroarylamino group may each independently be selected from a deuterium atom, a halogen atom, an unsubstituted alkyl group, an unsubstituted aryl group, an unsubstituted heteroaryl group, an unsubstituted alkoxy group, an unsubstituted aryloxy group, an unsubstituted heteroaryloxy group, an unsubstituted diarylamino group, an unsubstituted diheteroarylamino group, an unsubstituted arylheteroarylamino group, or a combination thereof.

[0054] Hereinafter, the compounds according to the present disclosure are sometimes referred to as "fused-ring compounds". In addition, an organic electroluminescent (EL) device is sometimes referred to as an "organic EL device".

[0055] The fused-ring compounds according to the present disclosure may exhibit a relatively narrow maximum (or peak) emission spectrum, achieve high color purity, and may also improve the luminous efficiency and / or lifetime of an organic EL device.

[0056] Although the inventors of the present disclosure may speculate on the mechanism for solving the technical problems in the art, any proposed mechanism or technical reason provided does not limit the scope of the present disclosure, and of course, the absence of the proposed mechanism or reason provided will not further limit the claims recited herein.

[0057] The fused-ring compounds of the present disclosure have an electron-donating nitrogen atom (N) and an electron-accepting boron atom (B), and the described compound structures allow these atoms to be arranged in a relatively rigid conjugated system. Due to the structural rigidity, changes in the molecular structure (bond lengths, bond angles, etc.) between the ground state (S0) and the first excited state (S1) can be suppressed, which in turn can provide a relatively narrow emission spectrum observed for the compounds. Thus, high color purity luminescence can be achieved, particularly high color purity blue luminescence with a narrow spectrum. Additionally, the electronic effects resulting from the described structural arrangements can contribute to increasing the oscillator strength and also to achieving emission intensity with high efficiency.

[0058] In addition, the fused-ring compounds of the present disclosure include a spiro ring structure represented by Formula 1 in the parent skeleton and thus have an improved three-dimensional volume height of the molecule. Therefore, Dexter energy transfer between the fused-ring compound and another compound can be suppressed, and thus, a blue EL device with a long lifetime can be achieved.

[0059] Particularly, an organic EL device including the fused-ring compound of the present disclosure and a thermally activated delayed fluorescence (TADF) material as luminescent materials in the emission layer can have suppressed Dexter energy transfer from the luminescent materials (particularly, phosphorescent materials). Thus, a blue EL device with high efficiency and a long lifetime can be achieved.

[0060] As stated, the above structural / electronic mechanisms are partially based on speculation, and whether the mechanism is correct or incorrect does not affect the technical scope of the present disclosure.

[0061] The polycyclic group structure represented by Formula 2 has two binding sites *1, and each binding site *1 represents a bonding point to the corresponding adjacent ring-forming atom in Ar in the structure represented by Formula 1, or each binding site *1 represents a bonding point to the corresponding adjacent ring-forming atom in Ar in the structure represented by Formula 1. The fused-ring compounds of the present disclosure can include one polycyclic group structure represented by Formula 2. 1 of the structure represented by Formula 1, or each binding site *1 represents a bonding point to the corresponding adjacent ring-forming atom in Ar in the structure represented by Formula 1. 2 The fused-ring compounds of the present disclosure can include one polycyclic group structure represented by Formula 2.

[0062] The group structure represented by Formula 3 has two binding sites *2, and each binding site *2 represents a bonding point to the corresponding adjacent ring-forming atom in Ar in the polycyclic group structure represented by Formula 2, or each binding site *2 represents a bonding point to the corresponding adjacent ring-forming atom in Ar in the polycyclic group structure represented by Formula 2. The fused-ring compounds of the present disclosure have at least one but no more than four group structures each represented by Formula 3, for example, no more than three or two group structures. 5 in the polycyclic group structure represented by Formula 2, or each binding site *2 represents a bonding point to the corresponding adjacent ring-forming atom in Ar in the polycyclic group structure represented by Formula 2. 6 The fused-ring compounds of the present disclosure have at least one but no more than four group structures each represented by Formula 3, for example, no more than three or two group structures.

[0063] As used herein, the term "number of ring-forming atoms" refers to the number of atoms in the ring itself of a compound (e.g., a monocyclic compound, a fused-ring compound, a carbocyclic compound, and a heterocyclic compound) that forms a structure in which the atoms are bonded in a cyclic manner (e.g., a monocyclic ring, a fused ring, and a ring assembly). The number of ring-forming atoms does not include the number of atoms that do not form a ring (e.g., hydrogen atoms that terminate the bonds of the atoms forming the ring) and the number of atoms included in a substituent when the ring is substituted with a substituent. Unless otherwise specified, the same definition of the number of ring-forming atoms applies to the description provided below.

[0064] For example, a benzene ring has 6 ring-forming atoms (or represents a six-membered ring), a naphthalene ring has 10 ring-forming atoms, a pyridine ring has 6 ring-forming atoms, and a furan ring has 5 ring-forming atoms (or represents a five-membered ring).

[0065] For example, when a benzene ring is substituted with an alkyl group as a substituent, the number of carbon atoms of the alkyl group is not included in the number of ring-forming atoms of the benzene ring. Thus, the number of ring-forming atoms of the benzene ring substituted with an alkyl group remains 6. For example, when a naphthalene ring is substituted with an alkyl group as a substituent, the number of atoms of the alkyl group is not included in the number of ring-forming atoms of the naphthalene ring. Thus, the number of ring-forming atoms of the naphthalene ring substituted with an alkyl group remains 10.

[0066] For example, the number of hydrogen atoms bonded to a pyridine ring or the number of atoms of a substituent constituting the pyridine ring is not included in the number of ring-forming atoms of the pyridine ring. Thus, the number of ring-forming atoms of the pyridine ring to which a hydrogen atom or a substituent is bonded remains 6.

[0067] In Formulas 1, 2, and 3, the aromatic hydrocarbon rings constituting Ar 1 to Ar 8 may each be a monocyclic ring or a fused ring. The number of ring-forming atoms of the aromatic hydrocarbon ring may be from 6 to 30, such as from 6 to 10, or such as 6. Examples of aromatic hydrocarbon rings having 6 to 30 ring-forming atoms may include, but are not particularly limited to, a benzene ring, a cyclopentadiene ring, an indene ring, a naphthalene ring, an anthracene ring, an azulene ring, a heptalene ring, an acenaphthene ring, a phenalene ring, a fluorene ring, a phenanthrene ring, a biphenyl ring, a terphenyl ring, a benzo[9,10]phenanthrene ring, a pyrene ring, a ring, a picene ring, a perylene ring, a pentaphene ring, a pentacene ring, a benzo[a]anthracene ring, a hexaphene ring, a hexacene ring, a rubicene ring, a terrylene ring, a heptaphene ring, a picene ring, etc. For example, the aromatic hydrocarbon ring may be a benzene ring.

[0068] In Formulas 1, 2, and 3, the heteroaromatic rings constituting Ar 1 to Ar 8 may each be a monocyclic ring or a fused ring. The number of ring-forming atoms of the heteroaromatic ring may be from 5 to 30, such as from 5 to 20, or such as from 5 to 18.

[0069] The heteroaromatic ring has one or more heteroatoms (e.g., nitrogen atom (N), oxygen atom (O), phosphorus atom (P), sulfur atom (S), and silicon atom (Si)) as ring-forming atoms, and the remaining ring-forming atoms are carbon atoms (C). Examples of heteroaromatic rings having 5 to 30 ring-forming atoms may include, but are not particularly limited to, pyridine ring, pyrazine ring, pyridazine ring, pyrimidine ring, triazine ring, quinoline ring, isoquinoline ring, quinoxaline ring, quinazoline ring, naphthyridine ring, acridine ring, phenazine ring, benzoquinoline ring, benzoisoquinoline ring, phenanthridine ring, phenanthroline ring, benzoquinone ring, coumarin ring, anthraquinone ring, fluorenone ring, furan ring, thiophene ring, benzofuran ring, benzothiophene ring, dibenzofuran ring, dibenzothiophene ring, pyrrole ring, indole ring, carbazole ring, indolocarbazole ring, imidazole ring, benzimidazole ring, pyrazole ring, indazole ring, oxazole ring, isoxazole ring, benzoxazole ring, benzisoxazole ring, thiazole ring, isothiazole ring, benzothiazole ring, benzisothiazole ring, imidazolinone ring, benzimidazolinone ring, imidazopyridine ring, imidazopyrimidine ring, imidazophenanthridine ring, benzimidazophenanthridine ring, azadibenzofuran ring, azacarbazole ring, azadibenzothiophene ring, diazadibenzofuran ring, diazacarbazole ring, diazadibenzothiophene ring, xanthone ring, thioxanthone ring, etc.

[0070] At least one hydrogen atom of the aromatic hydrocarbon ring and the heteroaromatic ring may be substituted. In this case, the type of substituent may be, but is not particularly limited to, deuterium atom, halogen atom, substituted or unsubstituted alkyl group, substituted or unsubstituted aryl group, substituted or unsubstituted heteroaryl group, substituted or unsubstituted alkoxy group, substituted or unsubstituted aryloxy group, substituted or unsubstituted heteroaryloxy group, substituted or unsubstituted diarylamino group, substituted or unsubstituted diheteroarylamino group, or substituted or unsubstituted arylheteroarylamino group. When two or more hydrogen atoms are substituted, the types of substituents may be the same as or different from each other.

[0071] Examples of the halogen atom as a substituent may include fluorine atom (F), chlorine atom (Cl), bromine atom (Br), iodine atom (I), etc.

[0072] The alkyl group as a substituent may be linear, branched, or cyclic. The number of carbon atoms in the alkyl group may be, but is not particularly limited to, 1 to 30, or for example 1 to 20. Additionally, the number of carbon atoms in the alkyl group may be 1 to 10, or for example 1 to 6. Examples of the alkyl group may include, but are not particularly limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, isobutyl, 2-ethylbutyl, 3,3-dimethylbutyl, n-pentyl, isopentyl, neopentyl, tert-pentyl (t-pentyl), cyclopentyl, 1-methylpentyl, 3-methylpentyl, 2-ethylpentyl, 4-methyl-2-pentyl, n-hexyl, 1-methylhexyl, 2-ethylhexyl, 2-butylhexyl, cyclohexyl, 4-methylcyclohexyl, 4-tert-butylcyclohexyl (4-t-butylcyclohexyl), n-heptyl, 1-methylheptyl, 2,2-dimethylheptyl, 2-ethylheptyl, 2-butylheptyl, n-octyl, tert-octyl (t-octyl), 2-ethyloctyl, 2-butyl octyl, 2-hexyloctyl, 3,7-dimethyloctyl, cyclooctyl, n-nonyl, n-decyl, adamantyl, 2-ethyldecyl, 2-butyldecyl, 2-hexyldecyl, 2-octyldecyl, n-undecyl, n-dodecyl, 2-ethyldodecyl, 2-butyldodecyl, 2-hexyldodecyl, 2-octyldodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, 2-ethylhexadecyl, 2-butyldecyl, 2-hexyldecyl, 2-octyldecyl, n-heptadecyl, n-octadecyl, n-nonadecyl, n-eicosyl, 2-ethyleicosyl, 2-butyleicosyl, 2-hexyleicosyl, 2-octyleicosyl, n-heneicosyl, n-docosyl, n-tricosyl, n-tetracosyl, n-pentacosyl, n-hexacosyl, n-heptacosyl, n-octacosyl, n-nonacosyl, n-triacontyl, and the like.

[0073] The aryl group as a substituent may be, but is not particularly limited to, a monovalent group derived from a hydrocarbon ring including one or more aromatic rings. Additionally, the hydrocarbon ring constituting the aryl group may be a fused ring. Additionally, when the aryl group includes two or more aromatic rings, the two or more aromatic rings may be bonded to each other via a single bond (in the form of a ring assembly of aromatic hydrocarbon rings). The number of ring-forming atoms in the aryl group may be, but is not particularly limited to, 6 to 30. Additionally, the number of ring-forming atoms in the aryl group may be 6 to 20, or for example 6 to 18. Examples of the aryl group may include, but are not particularly limited to, phenyl, naphthyl, phenanthryl, biphenyl, benzo[9,10]phenanthryl, anthryl, pyrenyl, fluorenyl, azulyl, acenaphthylenyl, fluoranthenyl, tetraphenyl, perylenyl, pentaphenyl, quaterphenyl, groups, etc.

[0074] The heteroaryl as a substituent may be, but is not particularly limited to, a monovalent group derived from a ring including one or more heteroaromatic rings and optionally one or more aromatic rings, the heteroaromatic ring having one or more heteroatoms (e.g., nitrogen atom (N), oxygen atom (O), phosphorus atom (P), sulfur atom (S), and silicon atom (Si)) as ring-forming atoms, wherein the remaining ring-forming atoms are carbon atoms (C). When the heteroaryl includes two or more heteroatoms, the heteroatoms may be the same as or different from each other. Additionally, the rings constituting the heteroaryl may be fused rings. Further, when the heteroaryl includes two or more heteroaromatic rings, the two or more heteroaromatic rings may be bonded to each other via a single bond.

[0075] Thus, the heteroaryl may be a monocyclic heteroaryl or a polycyclic heteroaryl. The number of ring-forming atoms of the heteroaryl may be, but is not particularly limited to, 5 to 30. Additionally, the number of ring-forming atoms of the heteroaryl may be 5 to 20, such as 5 to 18. Examples of the heteroaryl may include, but are not particularly limited to, thienyl, furyl, pyrrolyl, imidazolyl, thiazolyl, oxazolyl, oxadiazolyl, triazolyl, pyridyl, bipyridyl, pyrimidinyl, triazinyl, triazolyl, acridinyl, pyridazinyl, pyridyl, quinolinyl, quinazolinyl, quinoxalinyl, phenoxazinyl, phthalazinyl, pyridopyrimidinyl, pyridopyrazinyl, pyrazinopyrazinyl, isoquinolinyl, indolyl, carbazolyl, N-arylcarbazolyl, N-heteroarylcarbazolyl, N-alkylcarbazolyl, benzoxazolyl, benzimidazolyl, benzothiazolyl, benzocarbazolyl, benzothienyl, dibenzothienyl, thienothienyl, benzofuryl, phenanthrolinyl, thiazolyl, isoxazolyl, oxadiazolyl, thiadiazolyl, phenothiazinyl, dibenzothiophenylene, dibenzofuranyl, and combinations thereof.

[0076] The alkoxy group as a substituent may be linear, branched, or cyclic. The alkyl group constituting the alkoxy group is not particularly limited, and examples thereof may be the same as those described in the above description of the alkyl group. The number of carbon atoms of the alkoxy group may be, but is not particularly limited to, 1 or more. Additionally, the number of carbon atoms of the alkoxy group may be 20 or less, such as 10 or less, or such as 4 or less. Examples of the alkoxy group may include, but are not particularly limited to, methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, sec-butoxy, tert-butoxy, isobutoxy, 2-ethylbutoxy, 3,3-dimethylbutoxy, n-pentyloxy, isopentyloxy, neopentyloxy, tert-pentyloxy, cyclopentyloxy, 1-methylpentyloxy, 3-methylpentyloxy, 2-ethylpentyloxy, 4-methyl-2-pentyloxy, n-hexyloxy, 1-methylhexyloxy, 2-ethylhexyloxy, 2-butylhexyloxy, cyclohexyloxy, 4-methylcyclohexyloxy, 4-tert-butylcyclohexyloxy, n-heptyloxy, 1-methylheptyloxy, 2,2-dimethylheptyloxy, 2-ethylheptyloxy, 2-butylheptyloxy, n-octyloxy, tert-octyloxy, 2-ethyloctyloxy, 2-butyl octyloxy, 2-hexyloctyloxy, 3,7-dimethyloctyloxy, cyclooctyloxy, n-nonyloxy, n-decyloxy, adamantyloxy, etc.

[0077] The aryloxy group as a substituent is not particularly limited. The number of carbon atoms of the aryloxy group may be, but is not particularly limited to, 6 to 30. The number of carbon atoms of the aryloxy group may be 6 to 12, or such as 6. Examples of the aryloxy group may include, but are not particularly limited to, phenoxy, biphenyloxy, terphenyloxy, naphthyloxy, fluorenyloxy, anthryloxy, quaterphenyloxy, quinquephenyloxy, benzo[9,10]phenanthryloxy, pyrenyloxy, benzofluorenyloxy, oxy, and combinations thereof.

[0078] The heteroaryloxy as a substituent is not particularly limited. The heteroaryl constituting the heteroaryloxy is not particularly limited, and examples thereof may be the same as those described in the above description of heteroaryl. The number of carbon atoms of the heteroaryloxy may be, but is not particularly limited to, 5 to 30. In addition, the number of ring-forming atoms of the heteroaryloxy may be 5 to 14, or for example 5 to 13. The number of heteroatoms of the ring-forming atoms of the heteroaryloxy may be, but is not particularly limited to, 1 to 3. In addition, the number of heteroatoms of the ring-forming atoms of the heteroaryloxy may be 1 or 2, or for example 1. Examples of the heteroaryloxy may include, but are not particularly limited to, thiophenoxy, furanoxy, pyrrolyloxy, imidazolyloxy, thiazolyloxy, oxazolyloxy, oxadiazolyloxy, triazolyloxy, pyridyloxy, bipyridyloxy, pyrimidyloxy, triazinoxy, triazolyloxy, acridyloxy, pyridazinyloxy, pyridyloxy, quinolyloxy, quinazolinoxy, quinoxalinoxy, phenoxazinoxy, phthalazinyloxy, pyridopyrimidyloxy, pyridopyrazinyloxy, pyrazinopyrazinyloxy, isoquinolyloxy, indolyloxy, carbazolyloxy, benzoxazolyloxy, benzimidazolyloxy, benzothiazolyloxy, benzocarbazolyloxy, benzothiophenoxy, dibenzothiophenoxy, thienothiophenoxy, benzofuranoxy, phenanthrolinyloxy, thiazolyloxy, isoxazolyloxy, oxadiazolyloxy, thiadiazolyloxy, phenothiazinyloxy, dibenzothiolanyloxy, dibenzofuranoxy, xanthonyloxy, and combinations thereof.

[0079] The diarylamino, diheteroarylamino, and arylheteroarylamino as substituents are not particularly limited. Examples of the aryl and heteroaryl constituting the diarylamino, diheteroarylamino, and arylheteroarylamino may be the same as those described in the above descriptions of aryl and heteroaryl, respectively. Examples of the diarylamino may include, but are not particularly limited to, diphenylamino, bis(4-tert-butylphenyl)amino, phenyl(naphthyl)amino, bis(biphenyl)amino, bis(p-terphenyl)amino, etc. Examples of the arylheteroarylamino may include, but are not particularly limited to, phenyl(2-pyridyl)amino, etc. Examples of the diheteroarylamino may include, but are not particularly limited to, bis(2-pyridyl)amino, etc.

[0080] When the above (primary) substituents are further substituted, the type of additional (or secondary) substituents is not particularly limited. When the above substituents are further substituted by secondary substituents, the secondary substituents can be, for example, a deuterium atom, a halogen atom, an unsubstituted alkyl group, an unsubstituted aryl group, an unsubstituted heteroaryl group, an unsubstituted alkoxy group, an unsubstituted aryloxy group, an unsubstituted heteroaryloxy group, an unsubstituted diarylamino group, an unsubstituted diheteroarylamino group, or an unsubstituted arylheteroarylamino group. In the case where the above substituents are further substituted by substituents, when two or more substituents are further introduced into the above substituents, the types of the two or more substituents can be the same as or different from each other. In addition, the substituents further introduced into the above substituents may not substitute groups of the same type. For example, the substituents substituting an alkyl group as a substituent may not include an alkyl group. The unsubstituted alkyl group, unsubstituted aryl group, unsubstituted heteroaryl group, unsubstituted alkoxy group, unsubstituted aryloxy group, unsubstituted heteroaryloxy group, unsubstituted diarylamino group, unsubstituted diheteroarylamino group, and unsubstituted arylheteroarylamino group as secondary substituents can be respectively defined as above for the alkyl group, aryl group, heteroaryl group, alkoxy group, aryloxy group, heteroaryloxy group, diarylamino group, diheteroarylamino group, and arylheteroarylamino group as primary substituents.

[0081] For example, the substituent (primary or secondary) can independently be a deuterium atom, a halogen atom, C1-C 20 alkyl group (such as C1-C 20 (such as C1-C 10 ) linear alkyl group, or C3-C 20 (such as C3-C 10(branched alkyl), phenyl, tert-butyl, pyridyl, pyrrolyl, 4-tert-butylphenyl, 3-tert-butylphenyl, 2-tert-butylphenyl, 2-phenylphenyl, 2,6-diisopropylphenyl, 3,5-di-tert-butylphenyl, 2,6-di-tert-butylphenyl, 2,6-diphenylphenyl, 2,4-diphenylphenyl, 2,5-diphenylphenyl, 4-(4-tert-butylphenyl)phenyl, 2,6-bis(4-tert-butylphenyl)phenyl, 2,6-bis(3-tert-butylphenyl)phenyl, 4-(3,5-di-tert-butylphenyl)phenyl, 2,6-bis(3,5-di-tert-butylphenyl)phenyl, 4-tert-butyl-2,6-bis(4-tert-butylphenyl)phenyl, 2,4,5-triphenylphenyl, 2,4,6-triphenylphenyl, 2,4,6-tritert-butylphenyl, 4-(4-tert-butylphenyl)-2,5-diphenylphenyl, 4-(3,5-di-tert-butylphenyl)-2,5-diphenylphenyl, 5-tert-butyl-2,4-diphenylphenyl, 4-phenyl-2,6-di-tert-butylphenyl, 4-phenyl-2,5-di-tert-butylphenyl, carbazolyl, 1,8-dimethylcarbazolyl, 1,8-dimethyl-3,6-di-tert-butylcarbazolyl, 3,6-di-tert-butylcarbazolyl, diphenylamino, bis(2,6-dimethylphenyl)amino, bis(2,6-dimethyl-4-tert-butylphenyl)amino, or bis(4-tert-butylphenyl)amino.

[0082] In formula 2, X can be -O-, -S-, -NR 21 -, or -CR 22 R 23 -, where R 21 、R 22 and R 23 can each independently be hydrogen, deuterium, substituted or unsubstituted alkyl, substituted or unsubstituted aryl, or substituted or unsubstituted heteroaryl, where if X is -NR 21 -, then R 21 can be bonded to the ring-forming atoms of Ar 7 . Examples of the alkyl, aryl, and heteroaryl can be the same as the examples of the alkyl, aryl, and heteroaryl described in the above description of the substituents. For example, in formula 2, X can be -O- or -S-.

[0083] In formula 1, Z can be C or Si, for example, C.

[0084] In formula 3, Y can be -O-, -S-, or -NR 31 -, where R 31 can be hydrogen, deuterium, substituted or unsubstituted alkyl, substituted or unsubstituted aryl, or substituted or unsubstituted heteroaryl. Examples of the alkyl, aryl, and heteroaryl can be the same as the examples of the alkyl, aryl, and heteroaryl described in the above description of the substituents.

[0085] In an embodiment, the structure of Formula 1 can be represented by one of Formulas 1-1 to 1-6:

[0086]

[0087] Wherein, in Formulas 1-1 to 1-6,

[0088] R 11 and R 12 can each independently be deuterium, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group,

[0089] q and t can each independently be 0, 1, or 2, wherein when q is 2, the two Rs 11 can be the same as or different from each other, and when t is 2, the two Rs 12 can be the same as or different from each other,

[0090] s and r can each independently be 0, 1, 2, 3, or 4, wherein when s is 2 or greater, two or more Rs 12 can be the same as or different from each other, and when r is 2 or greater, two or more Rs 11 can be the same as or different from each other,

[0091] *3 represents an adjacent ring-forming carbon atom connected to the binding site *1 in the polycyclic group structure represented by Formula 2, and

[0092] Ar 3 、Ar 4 and Z can each be the same as those described in Formula 1.

[0093] The fused-ring compound of the present disclosure can be a compound having the following structure: wherein the polycyclic group structure represented by Formula 4 is connected to ring Ar 1 or ring Ar 2 in the structure represented by Formula 1, and at least one but no more than four group structures each represented by Formula 5 are connected to ring Ar 5 ' or ring Ar 6 in the polycyclic group structure represented by Formula 4.

[0094]

[0095] In Formula 4,

[0096] R 41 can be deuterium, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group,

[0097] n can be 0, 1, 2, or 3, wherein when n is 2 or greater, two or more Rs 41may be the same as or different from each other, and

[0098] Ar 6 、Ar 7 、X, and the binding site *1 may each be the same as those described in Formula 2.

[0099] In Formula 5,

[0100] Ar 9 may be a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 30 ring-forming atoms, or a substituted or unsubstituted heteroaromatic ring having 5 to 30 ring-forming atoms,

[0101] The binding site *2 may be bonded to adjacent ring-forming atoms of the ring Ar 5 ' or the ring Ar 6 and

[0102] Ar 8 may be the same as that described for Formula 3.

[0103] Regarding R 41 in Formula 4, examples include alkyl, aryl, and heteroaryl, and may be the same as the examples of alkyl, aryl, and heteroaryl described in the above description of substituents. Additionally, the substituents of substituted alkyl, substituted aryl, and substituted heteroaryl may be as described above for the substituents of the aromatic hydrocarbon rings and heteroaromatic rings of Ar 1 to Ar 8 .

[0104] Regarding Ar 9 in Formula 5, examples include aromatic hydrocarbon rings and heteroaromatic rings, and may be the same as the examples of aromatic hydrocarbon rings and heteroaromatic rings in Formula 1, 2, or 3. Additionally, the substituents of substituted aromatic hydrocarbon rings and substituted heteroaromatic rings may be as described above for the substituents of the aromatic hydrocarbon rings and heteroaromatic rings of Ar 1 to Ar 8 .

[0105] The fused-ring compound of the present disclosure may be a compound having the following structure: wherein the structure represented by Formula 6 is connected to adjacent ring-forming atoms of Ar 1 in the structure represented by Formula 1 or adjacent ring-forming atoms of Ar 2 .

[0106]

[0107] In Formula 6,

[0108] R 61 may be deuterium, a substituted or unsubstituted alkyl, a substituted or unsubstituted aryl, or a substituted or unsubstituted heteroaryl,

[0109] m can be 0 or 1,

[0110] Ar 6 and Ar 7 , X, and binding site *1 can each be the same as those described in Formula 2,

[0111] Ar 8 can be the same as that described in Formula 3, and

[0112] Ar 9 can be the same as that described in Formula 5.

[0113] Regarding R in Formula 6 61 , examples include alkyl, aryl, and heteroaryl, and can be the same as the examples of alkyl, aryl, and heteroaryl described in the above description of substituents. Additionally, the substituents of substituted alkyl, substituted aryl, and substituted heteroaryl can be as described above for the substituents of the aromatic hydrocarbon rings and heteroaromatic rings of Ar 1 to Ar 8 .

[0114] The fused-ring compound of the present disclosure can be a compound having the following structure: wherein the structure represented by Formula 7 is connected to the adjacent ring-forming atoms of Ar 1 in the structure represented by Formula 1 or the adjacent ring-forming atoms of Ar 2 .

[0115]

[0116] In Formula 7,

[0117] R 71 can be deuterium, substituted or unsubstituted alkyl, substituted or unsubstituted aryl, or substituted or unsubstituted heteroaryl,

[0118] o can be 0, 1, 2, 3, or 4, wherein when o is 2 or greater, two or more R 71 can be the same as or different from each other,

[0119] X and binding site *1 can each be the same as those described in Formula 2,

[0120] Ar 8 can be the same as that described in Formula 3,

[0121] Ar 9 can be the same as that described in Formula 5, and

[0122] R 61 and m can each be the same as those described in Formula 6.

[0123] Regarding R in Formula 7 71, examples include alkyl, aryl, and heteroaryl, and may be the same as the examples of alkyl, aryl, and heteroaryl described in the above description of substituents. Additionally, the substituents of substituted alkyl, substituted aryl, and substituted heteroaryl may be as described above for the substituents of the aromatic hydrocarbon rings and heteroaromatic rings of Ar 1 to Ar 8 .

[0124] In Formula 7,

[0125] R 72 may be deuterium, substituted or unsubstituted alkyl, substituted or unsubstituted aryl, or substituted or unsubstituted heteroaryl, and

[0126] p may be 0, 1, 2, or 3, where when p is 2 or greater, two or more R 72 may be the same as or different from each other.

[0127] Introducing an electron-donating group or an electron-withdrawing group as R in Formula 7 72 may affect the shape of the spectrum. Regarding R in Formula 7 72 , the examples of alkyl, aryl, and heteroaryl may be the same as the examples of alkyl, aryl, and heteroaryl described in the above description of substituents. Additionally, the substituents of substituted alkyl, substituted aryl, and substituted heteroaryl may be as described above for the substituents of the aromatic hydrocarbon rings and heteroaromatic rings of Ar 1 to Ar 8 .

[0128] Some examples of the polycyclic compounds according to the embodiments are provided below. For example, the polycyclic compounds of the present disclosure may be Compounds 1 to 109. However, the present disclosure is not limited to the following example compounds.

[0129]

[0130]

[0131]

[0132]

[0133]

[0134]

[0135]

[0136]

[0137]

[0138] The polycyclic compounds of the present disclosure may include at least one selected from the following: Compound 1, Compound 2, Compound 3, Compound 4, Compound 5, Compound 6, Compound 7, Compound 8, Compound 9, Compound 10, Compound 11, Compound 12, Compound 13, Compound 14, Compound 18, Compound 20, Compound 26, Compound 27, Compound 28, Compound 31, Compound 32, Compound 33, Compound 34, Compound 36, Compound 37, Compound 38, Compound 39, Compound 42, Compound 43, Compound 44, Compound 45, Compound 46, Compound 48, Compound 49, Compound 50, Compound 51, Compound 52, Compound 53, Compound 54, Compound 55, Compound 56, Compound 57, Compound 58, Compound 59, Compound 60, Compound 61, Compound 62, Compound 63, Compound 64, Compound 65, Compound 66, Compound 67, Compound 68, Compound 69, Compound 70, Compound 71, Compound 72, Compound 73, Compound 74, Compound 75, Compound 76, Compound 77, Compound 78, Compound 79, Compound 80, Compound 81, Compound 82, Compound 86, Compound 87, Compound 88, Compound 89, Compound 90, Compound 91, Compound 92, Compound 93, Compound 94, Compound 95, Compound 99, Compound 101, Compound 102, Compound 103, Compound 104, Compound 105, Compound 106, or Compound 107. The polycyclic compounds of the present disclosure may include at least one selected from Compound 1, Compound 2, Compound 3, or Compound 4.

[0139] In the polycyclic compounds of the present disclosure, the fluorescence wavelength peak obtained by converting the energy of the adiabatic first excited singlet state (S1) (hereinafter, also referred to as "adiabatic S1 excitation energy") (eV) into a light wavelength (nm), the oscillator strength f of the stable structure in the adiabatic first excited singlet state (S1), and the reorganization energy can be calculated by density functional theory (DFT) using the calculation software Gaussian 16 (Gaussian Inc.). A detailed description of each calculation method is provided in the examples.

[0140] In the polycyclic compounds of the present disclosure, the peak of the fluorescence wavelength obtained by converting the adiabatic S1 excitation energy (eV) into the optical wavelength (nm) is not particularly limited. In this regard, the maximum fluorescence wavelength peak can be from about 360 nm to about 515 nm. For example, the maximum fluorescence wavelength peak can be from about 380 nm to about 505 nm, or for example from about 400 nm to about 500 nm. Additionally, the maximum fluorescence wavelength peak can be from about 420 nm to about 490 nm. Further, the maximum fluorescence wavelength peak can be from about 430 nm to about 480 nm, or for example from about 440 nm to about 470 nm. When the maximum fluorescence wavelength peak is within the above ranges, a device including the polycyclic compound can achieve excellent light emission, particularly excellent blue light emission.

[0141] In addition, the range of the peak wavelength of the fluorescence in photoluminescence (PL) is the same as the range of the maximum fluorescence wavelength peak obtained by converting the adiabatic S1 excitation energy into the optical wavelength.

[0142] In the polycyclic compounds of the present disclosure, the spectral width of the fluorescence in PL (full width at half maximum (FWHM) of the fluorescence spectral peak) can be relatively narrower than that of compounds with similar structures in the art. In this regard, the spectral width of the fluorescence in PL can be 30 nm or less, or for example 25 nm or less (lower limit: greater than 0 nm). For example, the spectral width of the fluorescence in PL (FWHM) can be from 5 nm to 30 nm, or from 10 nm to 30 nm. When the spectral width of the fluorescence in PL is within the above ranges, a device including the polycyclic compound can achieve light emission with higher color purity.

[0143] In the polycyclic compounds of the present disclosure, the oscillator strength f of the stable structure in the adiabatic first excited singlet state (S1) can be, but is not particularly limited to, 0.22 or greater. Additionally, the oscillator strength f can be 0.30 or greater. Further, the oscillator strength f can be 0.40 or greater, or for example 0.50 or greater. When the oscillator strength f is within the above ranges, a device including the polycyclic compound can achieve high fluorescence intensity. Additionally, the theoretical upper limit of the oscillator strength f is the number of electrons included in the molecule. The upper limit of the oscillator strength f can be, for example, 2.0 or 3.0, but is not particularly limited thereto.

[0144] In the polycyclic compounds of the present disclosure, the reorganization energy can be 0.1 eV or less. For example, the reorganization energy can be 0.08 eV or less, or 0.07 eV or less. Additionally, the reorganization energy can be 0.065 eV or less, or for example 0.06 eV or less (lower limit: greater than 0 eV). When the reorganization energy is within the above ranges, a device including the polycyclic compound can achieve light emission with a narrower emission spectrum and higher color purity.

[0145] The singlet energy S1, the triplet energy T1, the peak wavelength of fluorescence in PL, and the spectral width (FWHM) of fluorescence in PL can each be measured using a fluorescence spectrophotometer F-7000 manufactured by Hitachi High-Tech Science Co., Ltd. A detailed description of each measurement method is provided in the Examples section.

[0146] The method for preparing the polycyclic compound according to the embodiment can be recognized by those skilled in the art by referring to the synthesis methods described in the Examples. Specifically, the polycyclic compound can be prepared, for example, according to the methods described in the Examples. For example, the compound can be prepared by: changing the raw materials or reaction conditions in the described method, adding some processes to the described method or excluding some processes from the described method, or appropriately combining the described method with alternatively known synthesis methods.

[0147] For example, Compounds 1 to 4 can be prepared by the methods described in the Examples.

[0148] The method for confirming the structure of the polycyclic compound according to the embodiment is not particularly limited. The structure of the polycyclic compound according to the embodiment can be confirmed by known methods (e.g., NMR, LC-MS, etc.).

[0149] Another aspect of the present disclosure relates to a material for an organic EL device, which includes the polycyclic compound of the present disclosure. The material for an organic EL device according to the embodiment may include the polycyclic compound and other materials, such as one or more host materials known to be used in organic EL devices.

[0150] Other materials used in the organic EL device may include, but are not particularly limited to, materials known in the art. For example, other materials used in the organic EL device may include materials constituting each layer described in the following description of the organic EL device. Among the materials constituting each layer, other materials used in the organic EL device may include at least one of the dopant material and the host material described in the following description of the emission layer. For example, other materials used in the organic EL device may include at least one selected from the TADF materials (TADF compounds), phosphorescent materials (phosphorescent compounds), and host materials described in the following description. Other materials used in the organic EL device may include (i) a host material or (ii) a host material and a TADF material or a phosphorescent material. Other materials used in the organic EL device may include a host material and a TADF material or a phosphorescent material. Other materials used in the organic EL device may include a host material and a phosphorescent material. The phosphorescent material may be the phosphorescent complex described in the following description of the emission layer. The phosphorescent material may be the platinum complex described in the following description.

[0151] Accordingly, an embodiment may include a material for an organic EL device that, in addition to one or more polycyclic compounds of the present disclosure, further includes at least one of a TADF material and a phosphorescent material described below. The phosphorescent material may be a phosphorescent complex or may be a platinum complex. When the material for an organic EL device, particularly the material for an emission layer, includes at least one of a TADF material and a phosphorescent material in addition to one or more polycyclic compounds of the present disclosure, the luminous efficiency and device lifetime of the organic EL device can be significantly improved.

[0152] In an embodiment, the material for an organic EL device may further include a solvent and may thus be a liquid material. The solvent may be, but is not particularly limited to, a solvent having a boiling point of about 100°C to about 350°C at atmospheric pressure (101.3 kPa, 1 atm). The boiling point of the solvent at atmospheric pressure may be about 150°C to about 320°C, or, for example, about 180°C to about 300°C. When the boiling point of the solvent at atmospheric pressure is within the above range, the film-forming properties or processability in a wet film-forming method (particularly in an inkjet method) can be improved.

[0153] The solvent having a boiling point of about 100°C to about 350°C is not particularly limited, and known solvents can be appropriately used. Hereinafter, the solvent having a boiling point of about 100°C to about 350°C will be described in detail, but the present disclosure is not limited thereto.

[0154] Examples of hydrocarbon-based solvents may include octane, nonane, decane, undecane, dodecane, etc. Examples of aromatic hydrocarbon-based solvents may include toluene, xylene, ethylbenzene, n-propylbenzene, isopropylbenzene, mesitylene, n-butylbenzene, sec-butylbenzene, 1-phenylpentane, 2-phenylpentane, 3-phenylpentane, phenylcyclopentane, phenylcyclohexane, 2-ethylbiphenyl, 3-ethylbiphenyl, etc. Examples of ether-based solvents may include 1,4-dioxane, 1,2-diethoxyethane, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, anisole, ethoxybenzene, 3-methylanisole, m-dimethoxybenzene, etc. Examples of ketone-based solvents may include 2-hexanone, 3-hexanone, cyclohexanone, 2-heptanone, 3-heptanone, 4-heptanone, cycloheptanone, etc. Examples of ester-based solvents may include butyl acetate, butyl propionate, heptyl butyrate, propylene carbonate, methyl benzoate, ethyl benzoate, 1-propyl benzoate, 1-butyl benzoate, etc. Examples of nitrile-based solvents may include benzonitrile, 3-methylbenzonitrile, etc. Examples of amide-based solvents may include dimethylformamide, dimethylacetamide, N-methylpyrrolidone, etc. Such solvents may be used alone or in combination of two or more.

[0155] The material for an organic EL device according to an embodiment may be a material for an emission layer.

[0156] The material for an organic EL device according to an embodiment may be, for example, the above-described material for an organic EL device that is not a liquid composition (i.e., substantially free of solvents). Additionally, even when the material for an organic EL device is not a liquid composition, the material for an organic EL device may be a material for an emission layer.

[0157] The expression "substantially free of solvents" means that, based on the total weight of the material (composition), the amount of solvent in the material is less than 1% by weight. When the material for an organic EL device is not a liquid composition, the material for an organic EL device may be substantially free of solvents, or may not include a solvent (where the amount of solvent is 0% by weight based on the total weight of the composition).

[0158] The amount of the polycyclic compound based on the total weight of the material for an organic EL device (particularly, the material for the emission layer) (excluding the total weight of the solvent in the case of a liquid composition) may be the same as the amount of the polycyclic compound based on the total weight of the emission layer of the organic EL device described below.

[0159] The amount of a TADF material or a phosphorescent material (particularly, a phosphorescent material) based on the total weight of the material for an organic EL device (particularly, the material for the emission layer) (excluding the total weight of the solvent in the case of a liquid composition) may be the same as the amount of the TADF material or the phosphorescent material (particularly, the phosphorescent material) based on the total weight of the emission layer of the organic EL device described below.

[0160] The amount (parts by weight) of the TADF material or the phosphorescent material (particularly, the phosphorescent material) based on 100 parts by weight of the polycyclic compound in the material for an organic EL device (particularly, the material for the emission layer) may be the same as the amount (parts by weight) of the TADF material or the phosphorescent material (particularly, the phosphorescent material) based on 100 parts by weight of the polycyclic compound in the emission layer of the organic EL device described below.

[0161] The amount of the host material based on the total weight of the material for an organic EL device (particularly, the material for the emission layer) (excluding the total weight of the solvent in the case of a liquid composition) may be the same as the amount of the host material based on the total weight of the emission layer of the organic EL device described below.

[0162] The amount (parts by weight) of the host material based on 100 parts by weight of the polycyclic compound in the material for an organic EL device (particularly, the material for the emission layer) may be the same as the amount (parts by weight) of the host material based on 100 parts by weight of the polycyclic compound in the emission layer of the organic EL device described below.

[0163] When the amounts of the polycyclic compound, the TADF material, or the phosphorescent material, and the host material in the materials for the organic EL device (particularly, the materials for the emission layer) are within the above ranges, respectively, an organic EL device having excellent emission color purity, high emission efficiency, and long lifetime can be achieved.

[0164] Another aspect of the present disclosure relates to a composition including one or more of the polycyclic compounds. The composition according to an embodiment may include the polycyclic compound and other materials used in the organic EL device.

[0165] The types of the other materials used in the organic EL device and the amounts of the other materials in the composition are the same as those described above for the materials for the organic EL device, and thus, the description thereof is omitted.

[0166] In an embodiment, a composition including at least one of a TADF material and a phosphorescent material in addition to the polycyclic compound may be provided. The phosphorescent compound may be a phosphorescent complex, for example, may be a phosphorescent platinum complex. When the materials for the organic EL device (particularly, the materials for the emission layer) include a TADF material or a phosphorescent material in addition to one or more of the polycyclic compounds, the emission efficiency and the device lifetime of the organic EL device can be significantly improved.

[0167] Another aspect of the present disclosure relates to an organic EL device having an organic layer including one or more of the polycyclic compounds. The organic EL device may exhibit a relatively narrow emission spectrum, can achieve emission with high color purity, and can achieve high emission efficiency and / or long lifetime.

[0168] Hereinafter, the organic EL device according to an embodiment will be described in detail with reference to the drawings. Figure 1 、 2 FIGS. 1, 2, and 3 are each a schematic diagram showing an organic EL device according to an embodiment. However, the structure of the organic EL device according to the present disclosure is not limited to Figures 1 to 3 the embodiment shown in FIGS.

[0169] Figure 1 FIG. 4 is a schematic cross-sectional view showing an organic EL device 10 according to an embodiment. The organic EL device 10 according to an embodiment may include a substrate 1, a first electrode 2, a hole transport region 3, an emission layer 4, an electron transport region 5, and a second electrode 6, which are sequentially stacked in the stated order as shown.

[0170] Figure 2 FIG. 4 is a schematic cross-sectional view showing an organic EL device 10 according to an embodiment. The organic EL device 10 may include a substrate 1, a first electrode 2, a hole transport region 3, an emission layer 4, an electron transport region 5, and a second electrode 6, which are sequentially stacked in the stated order. InFigure 2 In this case, the hole transport region 3 may include a hole injection layer 31 and a hole transport layer 32, which are stacked in the stated order. The electron transport region 5 may include an electron transport layer 52 and an electron injection layer 51, which are stacked in the stated order.

[0171] Figure 3 FIG. is a schematic cross-sectional view showing an organic EL device 10 according to an embodiment. The organic EL device 10 according to the embodiment may include a substrate 1, a first electrode 2, a hole transport region 3, an emission layer 4, an electron transport region 5, and a second electrode 6, which are stacked in the stated order. In Figure 3 In this case, the hole transport region 3 includes a hole injection layer 31, a hole transport layer 32, and an electron blocking layer 33, which are stacked in the stated order. Further, in Figure 3 In this case, the electron transport region 5 may include a hole blocking layer 53, an electron transport layer 52, and an electron injection layer 51, which are stacked in the stated order.

[0172] One or more of the polycyclic compounds according to the present disclosure may be included, for example, in any organic layer disposed between the first electrode 2 and the second electrode 6. The organic layer may be a hole injection layer 31, a hole transport layer 32, an emission layer 4, an electron transport layer 52, an electron injection layer 51, or the like. For example, the polycyclic compound according to the present disclosure may be included in the emission layer 4.

[0173] Embodiments may include, for example, an organic EL device including a first electrode, a second electrode, and a single or multiple emission layers. For example, the second electrode may be disposed on the first electrode.

[0174] As used herein, when a part of a layer, film, region, plate, etc. is referred to as being "under" or "beneath" another part, this includes not only the case where the part is "directly under" the other part, but also the case where there is an intermediate layer therebetween. As used herein, being disposed "on" includes not only being disposed on the upper surface, but also being disposed on the lower surface or bottom surface.

[0175] As described above, one or more of the polycyclic compounds according to the present disclosure may be included in the emission layer. That is, the organic layer may be an emission layer. Hereinafter, embodiments in which the polycyclic compound according to the present disclosure is included in the emission layer will be described. Further, the polycyclic compound according to the present disclosure included in the emission layer may be a single compound or a combination of two or more compounds.

[0176] The emission layer may be a single layer including a single material or a single layer including a plurality of different materials. Further, the emission layer may have a multilayer structure including a plurality of layers including a plurality of different materials.

[0177] The amount of the one or more polycyclic compounds based on the total weight of the emission layer may be, but is not particularly limited to, 0.05% by weight or more. For example, the amount may be 0.1% by weight or more, or 0.2% by weight or more. The amount of the polycyclic compound based on the total weight of the emission layer may be 50% by weight or less. For example, the amount may be 30% by weight or less, or for example 25% by weight or less. Within the above ranges, an organic EL device having excellent emission color purity, higher emission efficiency, and longer lifetime can be achieved.

[0178] The emission layer may include, for example, a host material and a dopant material. The polycyclic compound may be used as a host material or a dopant material, and for example, may be used as a dopant material.

[0179] The emission layer may further include, for example, known materials for the emission layer. For example, in addition to the polycyclic compound, the emission layer may further include anthracene derivatives, pyrene derivatives, fluoranthene derivatives, derivatives, dihydrobenzanthracene derivatives, or benzo[9,10]phenanthrene derivatives.

[0180] In addition, in addition to the polycyclic compound, the emission layer may further include known TADF compounds. The term "thermally activated delayed fluorescence" refers to the phenomenon in which reverse intersystem crossing from triplet excitons to singlet excitons occurs in compounds having a small energy difference (ΔE ST ) between the singlet energy level and the triplet energy level. The term "TADF material" refers to a material in which such a phenomenon occurs.

[0181] Examples of TADF materials may include the following compounds.

[0182]

[0183]

[0184]

[0185] TADF materials may be used alone or in combination of two or more.

[0186] In addition, in addition to the polycyclic compound, the emission layer may further include a phosphorescent material (phosphorescent compound). The phosphorescent material (phosphorescent compound) is not particularly limited, and known compounds that exhibit phosphorescence may be used. Among known compounds, the phosphorescent material (phosphorescent compound) may be a phosphorescent complex, and for example, may be a phosphorescent platinum complex.

[0187] Examples of the phosphorescent material (phosphorescent compound) may include the following compounds.

[0188]

[0189]

[0190]

[0191]

[0192] Such phosphorescent materials (phosphorescent compounds) can be used alone or in combination of two or more.

[0193] When the emission layer includes at least one of a TADF material and a phosphorescent material in addition to the condensed-ring compound of the present disclosure, the luminous efficiency and device lifetime of the organic EL device can be significantly improved.

[0194] In the emission layer of an organic EL device, singlet excitons and triplet excitons are generated in a ratio of 1:3 by the recombination of holes and electrons. In a device including only a fluorescent material as a light-emitting material, only singlet excitons are involved in light emission, while in a device including a TADF material or a phosphorescent material as a light-emitting material, both singlet excitons and triplet excitons can be used for light emission. Therefore, the luminous efficiency of a device including a TADF material or a phosphorescent material as a light-emitting material can be significantly improved. Excitons generated on the TADF material or the phosphorescent material can generally have a long lifetime of 1 μs or more. As a result, the excitons are in an unstable state with high energy. Therefore, when excitons are present, material deterioration can occur, leading to a reduction in device lifetime. When a TADF material or a phosphorescent material is also present in the emission layer in addition to the condensed-ring compound, excitons are efficiently generated on the TADF material or the phosphorescent material. In addition, energy can be transferred from the excitons to the condensed-ring compound by the Förster resonance energy transfer (FRET) mechanism. As a result, high-efficiency fluorescence can be obtained from the condensed-ring compound, and the time during which excitons are present on the TADF material or the phosphorescent material can be shortened. Therefore, the possibility of material (device) deterioration can be significantly reduced, and the device lifetime can be significantly improved.

[0195] The amount of at least one of a TADF material and a phosphorescent material (particularly, the phosphorescent material) based on the total weight of the emission layer can be, but is not particularly limited to, 0.1 wt% or more. For example, the amount can be 0.5 wt% or more, or 1 wt% or more. The amount can be 3 wt% or more, or 5 wt% or more. The amount of at least one of a TADF material and a phosphorescent material (particularly, the phosphorescent material) based on the total weight of the emission layer can be 50 wt% or less. For example, the amount can be 40 wt% or less, or 30 wt% or less. When the emission layer includes both a TADF material and a phosphorescent material, the total amount can be within the above range. Within the above range, an organic EL device having excellent luminous color purity, higher luminous efficiency, and longer lifetime can be achieved.

[0196] When the emission layer includes at least one of a TADF material and a phosphorescent material (particularly, a phosphorescent material), based on 100 parts by weight of the polycyclic compound, the amount thereof may be, but is not particularly limited to, 100 parts by weight or more. For example, based on 100 parts by weight of the polycyclic compound, the amount may be 150 parts by weight or more, or 200 parts by weight or more. Based on 100 parts by weight of the polycyclic compound, the amount of at least one of the TADF material and the phosphorescent material (particularly, the phosphorescent material) may be 10,000 parts by weight or less. For example, based on 100 parts by weight of the polycyclic compound, the amount may be 7,500 parts by weight or less, or 5,000 parts by weight or less. When the emission layer includes both the TADF material and the phosphorescent material, the total amount thereof may be within the above range. Within the above range, an organic EL device having excellent emission color purity, higher emission efficiency, and longer lifetime can be achieved.

[0197] The emission layer may include, for example, known host materials. The emission layer may include, for example, at least one of the following: bis[2-(diphenylphosphino)phenyl]ether oxide (DPEPO), 4,4'-bis(carbazol-9-yl)biphenyl (CBP), 3,3'-bis(carbazol-9-yl)biphenyl (mCBP), 1,3-bis(carbazol-9-yl)benzene (mCP), 2,8-bis(diphenylphosphoryl)dibenzofuran (PPF), 4,4',4''-tris(carbazol-9-yl)triphenylamine (TCTA), and 1,3,5-tris(N-phenylbenzimidazol-2-yl)benzene (TPBi). However, the host material is not limited thereto, and the emission layer may include, for example, tris(8-hydroxyquinoline)aluminum (Alq3), 4,4'-bis(N-carbazolyl)-1,1'-biphenyl (CBP), poly(N-vinylcarbazole) (PVK), 9,10-bis(naphthalen-2-yl)anthracene (ADN), 4,4',4''-tris(carbazol-9-yl)-triphenylamine (TCTA), 1,3,5-tris(N-phenylbenzimidazol-2-yl)benzene (TPBi), 3-tert-butyl-9,10-bis(naphthalen-2-yl)anthracene (TBADN), stilbenylarylene (DSA), 4,4'-bis(9-carbazolyl)-2,2'-dimethyl-biphenyl (CDBP), 2-methyl-9,10-bis(naphthalen-2-yl)anthracene (MADN), bis[2-(diphenylphosphino)phenyl]ether oxide (DPEPO), hexaphenylcyclotriphosphazene (CP1), 1,4-bis(triphenylsilyl)benzene (UGH2), hexaphenylcyclotrisiloxane (DPSiO3), octaphenylcyclotetrasiloxane (DPSiO4), or 2,8-bis(diphenylphosphoryl)dibenzofuran (PPF).

[0198] In addition, the emission layer may include a material having a highest occupied molecular orbital (HOMO) of -5.2 eV or less as a host material. In addition, the emission layer may include a material having a lowest unoccupied molecular orbital (LUMO) of -1.4 eV or less as a host material. By using a host material having a low HOMO and LUMO and high electron transport performance, the driving durability in an organic EL device (particularly, a blue organic EL device) can be improved. Such materials are not particularly limited, and examples thereof may be compounds represented by Formula A, which are disclosed in “An Alternative Host Material for Long-Lifespan Blue Organic Light-Emitting Diodes Using Thermally Activated Delayed Fluorescence” by Soo-Ghang Ihn et al., Advanced Science News 2017, 4, 1600502. When combined with such a host material to form an emission layer, a blue light-emitting material in the related art may become a deep hole trap, thereby causing undesirable effects such as an increase in driving voltage. The polycyclic compound of the present disclosure has weak hole trapping properties, and thus, it is expected to suppress an increase in driving voltage.

[0199] Formula A

[0200]

[0201] In addition, the emission layer may include the following compound as a host material.

[0202]

[0203] Among the above compounds, the emission layer may include at least one of Compound HT1 and Compound HT2 as a host material. For example, it may include both Compound HT1 and Compound HT2 as a host material.

[0204] The amount of the host material based on the total weight of the emission layer may be, but is not particularly limited to, 5% by weight or more. For example, the amount may be 10% by weight or more, or 20% by weight or more. The amount of the host material based on the total weight of the emission layer may be 99% by weight or less. For example, the amount may be 95% by weight or less, or 90% by weight or less. Within the above ranges, an organic EL device having excellent luminous color purity, high luminous efficiency, and long lifespan can be achieved.

[0205] When the emission layer includes a host material, based on 100 parts by weight of the polycyclic compound, the amount thereof may be, but is not particularly limited to, 1,000 parts by weight or more. For example, based on 100 parts by weight of the polycyclic compound, the amount may be 2,000 parts by weight or more, or for example 3,000 parts by weight or more. Based on 100 parts by weight of the polycyclic compound, the amount of the host material may be 200,000 parts by weight or less. For example, based on 100 parts by weight of the polycyclic compound, the amount may be 150,000 parts by weight or less, or 100,000 parts by weight or less. Within the above ranges, an organic EL device having excellent emission color purity, high emission efficiency, and long lifetime can be achieved.

[0206] The emission layer may include, for example, known dopant materials. For example, the emission layer may include styryl derivatives (e.g., 1,4-bis[2-(3-N-ethylcarbazolyl)vinyl]benzene (BCzVB), 4-(di-p-tolylamino)-4'-[(di-p-tolylamino)styryl]stilbene (DPAVB), or N-4(-((E)-2-(6-((E)-4-(diphenylamino)styryl)naphthalen-2-yl)vinyl)phenyl)-N-phenylaniline (N-BDAVBi)), perylene or its derivatives (e.g., 2,5,8,11-tetra-tert-butylperylene (TBP)), or pyrene or its derivatives (e.g., 1,1-dipyrene, 1,4-dipyrenylbenzene, or 1,4-bis(N,N-diphenylamino)pyrene).

[0207] The emission layer may be a single layer including a single material or a single layer including a plurality of different materials. Additionally, the emission layer may have a multilayer structure including a plurality of layers each including a plurality of different materials.

[0208] The thickness of the emission layer may be, but is not particularly limited to, about 1 nm to about 100 nm, or for example about 10 nm to about 30 nm.

[0209] The emission wavelength of the emission layer (i.e., the emission wavelength of the organic EL device including the emission layer) is not particularly limited. However, the emission layer may emit light having a peak in the wavelength range of about 360 nm to about 515 nm. The emission layer may emit, for example, light having a peak in the wavelength range of about 380 nm to about 505 nm. The emission layer may emit, for example, light having a peak in the wavelength range of about 400 nm to about 500 nm. The emission layer may emit, for example, light having a peak in the wavelength range of about 420 nm to about 470 nm. The emission layer may emit, for example, light having a peak in the wavelength range of about 430 nm to about 465 nm. Within the above ranges, excellent emission (particularly, excellent blue emission) can be achieved.

[0210] The emission spectral width of the emission layer (FWHM of the emission spectral peak), i.e., the emission spectral width of the organic EL device including the emission layer, can be relatively narrow. In this regard, the emission spectral width can be 30 nm or less, for example 25 nm or less, or for example 24 nm or less (lower limit: greater than 0 nm). Within the above range, light emission with high color purity can be obtained.

[0211] Examples of the film-forming method of the emission layer may include, but are not particularly limited to, known film-forming methods such as vacuum deposition, spin coating, Langmuir-Blodgett (LB) deposition, inkjet printing, laser printing, laser-induced thermal imaging (LITI), etc.

[0212] Hereinafter, the substrate, each region, and each layer will be described in detail.

[0213] The organic EL device 10 may include a substrate 1. As the substrate 1, a substrate used in a normal organic EL device can be used. For example, the substrate 1 can be a glass substrate, a semiconductor substrate such as a silicon substrate, or a transparent plastic substrate.

[0214] The first electrode 2 can have conductivity. In the organic EL device 10 according to the embodiment, the first electrode 2 can be an anode. For example, the first electrode 2 can be a pixel electrode. The first electrode 2 can be a transmissive electrode, a semi-transmissive semi-reflective electrode, or a reflective electrode.

[0215] The material for forming the first electrode 2 is not particularly limited, and examples thereof can be a metal, a metal alloy, or a conductive compound. When the first electrode 2 is a transmissive electrode, the first electrode 2 can include a transparent metal oxide, for example, indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium tin zinc oxide (ITZO), etc. When the first electrode 2 is a semi-transmissive semi-reflective electrode or a reflective electrode, the first electrode 2 can include Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF / Ca, LiF / Al, Mo, Ti, or a compound or mixture thereof (for example, a mixture of Ag and Mg).

[0216] The first electrode 2 can be a single layer including a single material or a single layer including a plurality of different materials. Alternatively, the first electrode 2 can have a multilayer structure including a plurality of layers including a plurality of different materials.

[0217] The thickness of the first electrode 2 can be, but is not particularly limited to, about 10 nm to about 1,000 nm, for example about 100 nm to about 300 nm.

[0218] The hole transport region 3 can be provided on the first electrode 2. The hole transport region 3 can include at least one of a hole injection layer 31, a hole transport layer 32, a hole buffer layer (not shown), and an electron blocking layer 33.

[0219] The hole transport region 3 can be a single layer including a single material or a single layer including a plurality of different materials. Additionally, the hole transport region 3 can have a multi-layer structure including a plurality of layers including a plurality of different materials.

[0220] For example, the hole transport region 3 can have a single layer structure including a hole injection layer 31 or a hole transport layer 32. The hole transport region 3 can have a single layer structure including a hole injection material and a hole transport material. The hole transport region 3 can have a hole injection layer 31 / hole transport layer 32 structure, in which the constituent layers are sequentially stacked in the stated order starting from the first electrode 2. The hole transport region 3 can have a hole injection layer 31 / hole transport layer 32 / hole buffer layer (not shown) structure. The hole transport region 3 can have a hole injection layer 31 / hole buffer layer (not shown) structure, in which the constituent layers are sequentially stacked in the stated order starting from the first electrode 2. The hole transport region 3 can have a hole transport layer 32 / hole buffer layer (not shown) structure, in which the constituent layers are sequentially stacked in the stated order starting from the first electrode 2. The hole transport region 3 can have a hole injection layer 31 / hole transport layer 32 / electron blocking layer 33 structure, in which the constituent layers are sequentially stacked in the stated order starting from the first electrode 2. However, the structure of the hole transport region 3 is not limited to the above examples.

[0221] There is no particular limitation on the hole injection layer 31 or other layers constituting the hole transport region 3, and it can include, for example, known hole injection materials. Examples of hole injection materials can include phthalocyanine compounds such as copper phthalocyanine, N,N'-diphenyl-N,N'-bis-[4-phenyl-m-tolyl-amino)-phenyl]-biphenyl-4,4'-diamine (DNTPD), 4,4',4"-tris(3-methylphenylphenylamino)triphenylamine (m-MTDATA), 4,4',4"-tris(N,N-diphenylamino)triphenylamine (TDATA), 4,4',4"-tris{N-(2-naphthyl)-N-phenylamino}-triphenylamine (2-TNATA), poly(3,4-ethylenedioxythiophene) / poly(4-styrenesulfonic acid) (PEDOT / PSS), polyaniline / dodecylbenzenesulfonic acid (PANI / DBSA), polyaniline / camphorsulfonic acid (PANI / CSA), polyaniline / poly(4-styrenesulfonic acid) (PANI / PSS), N,N'-bis(naphthalen-1-yl)-N,N'-diphenyl-benzidine (NPB), polyether ketone including triphenylamine (TPAPEK), 4-isopropyl-4'-methyldiphenyliodonium tetrakis(pentafluorophenyl)borate, 2,3,6,7,10,11-hexacynodipyrido[2,3-f:2',3'-h]quinoxaline (HAT-CN), 1,3,4,5,7,8-hexafluorotetracyano-2,6-naphthoquinodimethane (F6-TCNNQ), etc.

[0222] In addition, the hole transport layer 32 or other layers constituting the hole transport region 3 are not particularly limited and may include, for example, known hole transport materials. Examples of hole transport materials may include N-phenylcarbazole, carbazole-based derivatives such as polyvinylcarbazole, fluorene-based derivatives, N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1-biphenyl]-4,4'-diamine (TPD), triphenylamine-based derivatives such as 4,4',4''-tris(N-carbazolyl)triphenylamine (TCTA), N,N'-di(naphthalen-1-yl)-N,N'-diphenyl-benzidine (NPB), 4,4'-cyclohexylidenebis[N,N-bis(4-methylphenyl)aniline] (TAPC), 4,4'-bis[N,N'-(3-tolyl)amino]-3,3'-dimethylbiphenyl (HMTPD), 1,3-bis(N-carbazolyl)benzene (mCP), compound H1, compound H2, compound HT3, etc.

[0223]

[0224]

[0225] In addition to the hole injection material or the hole transport material, the hole transport region 3 may further include a charge generation material to improve conductivity. The charge generation material may be uniformly or non-uniformly dispersed in the hole transport region 3 or its respective layers. The charge generation material is not particularly limited, and examples thereof may be known charge generation materials. Examples of the charge generation material may be p-dopants. Examples of p-dopants may include quinone derivatives such as tetracyanoquinodimethane (TCNQ) or 2,3,5,6-tetrafluoro-tetracyanoquinodimethane (F4-TCNQ), metal oxides such as tungsten oxide or molybdenum oxide, cyanide-containing compounds, etc.

[0226] The hole buffer layer (not shown) can increase the light emission efficiency by compensating for the optical resonance distance according to the wavelength of the light emitted by the emission layer 4. The material included in the hole buffer layer (not shown) is not particularly limited, and materials used in known hole buffer layers can be used. For example, compounds that can be included in the hole transport region 3 can be used.

[0227] The electron blocking layer 33 can prevent electrons from being injected from the electron transport region 5 into the hole transport region 3. The material included in the electron blocking layer 33 is not particularly limited, and materials used in known electron blocking layers can be used. For example, host materials included in the emission layer 4 such as compound H-H1 and HT1 as host materials can be used.

[0228] The thickness of the hole transport region 3 may be, but is not particularly limited to, about 1 nm to about 1,000 nm, or for example about 10 nm to about 500 nm. For example, regarding each layer constituting the hole transport region 3, the thickness of the hole injection layer 31 may be, but is not particularly limited to, about 3 nm to about 100 nm. The thickness of the hole transport layer 32 may be, but is not particularly limited to, about 3 nm to about 200 nm, or for example about 3 nm to about 100 nm. The thickness of the electron blocking layer 33 may be, but is not particularly limited to, about 1 nm to about 100 nm. The thickness of the hole buffer layer (not shown) is not particularly limited as long as the hole buffer layer functions as a hole buffer layer and does not interfere with the function of the organic EL device. When the thickness of the hole transport region 3, the hole injection layer 31, the hole transport layer 32, or the electron blocking layer 33 is within the above range, excellent hole transport characteristics can be obtained without a significant increase in the driving voltage.

[0229] Examples of the film formation method of the hole transport region 3 or its respective layers may include, but are not particularly limited to, known film formation methods such as vacuum deposition, spin coating, LB deposition, inkjet printing, laser printing, LITI, etc.

[0230] The emission layer 4 may be disposed on the hole transport region 3. Details of the emission layer 4 may be the same as those described above.

[0231] The electron transport region 5 may be disposed on the emission layer 4. The electron transport region 5 may include at least one of an electron injection layer 51, an electron transport layer 52, and a hole blocking layer 53, but the embodiments are not limited thereto.

[0232] The electron transport region 5 may be a single layer including a single material or a single layer including a plurality of different materials. Alternatively, the electron transport region 5 may have a multi-layer structure including a plurality of layers including a plurality of different materials. The electron transport region 5 may have a single layer structure including an electron injection layer 51 or an electron transport layer 52. The electron transport region 5 may have a single layer structure including an electron injection material and an electron transport material. Alternatively, the electron transport region 5 may have an electron transport layer 52 / electron injection layer 51 structure, in which the constituent layers are stacked in the stated order starting from the emission layer 4. The electron transport region 5 may have a hole blocking layer 53 / electron transport layer 52 / electron injection layer 51 structure, in which the constituent layers are stacked in the stated order starting from the emission layer 4. However, the structure of the electron transport region 5 is not limited to the above examples. The electron injection layer 51 or other layers constituting the electron transport region 5 are not particularly limited and may include, for example, known electron injection materials. Examples of the electron injection material may include lithium quinolate (LiQ), Li2O, BaO, lanthanide metals such as Yb, metal halides such as LiF, NaCl, CsF or RbCl, etc. The electron injection layer 51 is not particularly limited and may include, for example, the electron transport materials and insulating organic metal salts described below. The organic metal salts are not particularly limited and may be, for example, materials having a band gap of 4 eV or more. Examples of the organic metal salts may include metal acetates, metal benzoates, metal acetoacetates, metal acetylacetonates, metal stearates, etc.

[0233] There is no particular limitation on the electron transport layer 52 or other layers constituting the electron transport region 5, and it may include, for example, known electron transport materials. Examples of electron transport materials may include anthracene-based compounds, tris(8-hydroxyquinoline)aluminum (Alq3), 1,3,5-tris[(3-pyridinyl)-pent-3-yl]benzene, 2,4,6-tris(3'-pyridin-3-yl)biphenyl-3-yl)-1,3,5-triazine, 2-(4-(N-phenylbenzimidazol-1-yl)phenyl)-9,10-dinaphthylanthracene, 1,3,5-tris(1-phenyl-1H-benzo[d]imidazol-2-yl)benzene (TPBi), 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), 4,7-diphenyl-1,10-phenanthroline (Bphen), 3-(4-biphenylyl)-4-phenyl-5-tert-butylphenyl-1,2,4-triazole (TAZ), 3-(4-biphenylyl)-4-phenyl-5-tert-butylpropyl-1,2,4-triazole (NTAZ), 2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (tBu-PBD), bis(2-methyl-8-hydroxyquinoline-N1,O8)-(1,1'-biphenyl-4-ol)aluminum (BAlq), bis(benzoquinoline-10-hydroxy)beryllium (Bebq2), 9,10-di(naphthalen-2-yl)anthracene (ADN), lithium hydroxyquinolate (LiQ), compound ET1, compound H91, etc.

[0234]

[0235] The hole blocking layer 53 can prevent holes from being injected from the hole transport region 3 into the electron transport region 5. There is no particular limitation on the material included in the hole blocking layer 53, and materials used in known hole blocking layers can be used. The hole blocking layer 53 may include, for example, known hole blocking materials. Examples of hole blocking materials may include 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), 4,7-diphenyl-1,10-phenanthroline (BPhen), etc. Additionally, examples of hole blocking materials may include host materials included in the emission layer 4 such as compound H-E1 and HT2 as host materials.

[0236] The thickness of the electron transport region 5 may be, but is not particularly limited to, about 0.1 nm to about 210 nm. The thickness of the electron transport region 5 may be about 30 nm to about 150 nm, or for example about 100 nm to about 150 nm. For example, regarding each layer constituting the electron transport region 5, the thickness of the electron transport layer 52 may be, but is not particularly limited to, about 10 nm to about 100 nm, or for example about 15 nm to about 50 nm. The thickness of the hole blocking layer 53 may be, but is not particularly limited to, about 10 nm to about 100 nm, or for example about 15 nm to about 50 nm. The thickness of the electron injection layer 51 may be, but is not particularly limited to, about 0.1 nm to about 10 nm, or for example about 0.3 nm to about 9 nm. When the thickness of the electron injection layer 51 is within the above range, excellent electron injection characteristics can be obtained without a significant increase in the driving voltage. For example, when the thickness of the electron transport region 5, the electron injection layer 51, the electron transport layer 52, or the hole blocking layer 53 is within the above range, excellent electron transport characteristics can be obtained without a significant increase in the driving voltage.

[0237] Examples of the film forming method of the electron transport region 5 and its respective layers may include, but are not particularly limited to, known film forming methods such as vacuum deposition, spin coating, LB deposition, inkjet printing, laser printing, LITI, etc.

[0238] The second electrode 6 may be disposed on the electron transport region 5. The second electrode 6 may have conductivity. In the organic EL device 10 according to an embodiment, the second electrode 6 may be a common electrode or a cathode. Additionally, the second electrode 6 may be a transmissive electrode, a semi-transmissive semi-reflective electrode, or a reflective electrode.

[0239] The material for forming the second electrode 6 is not particularly limited, and examples thereof may be a metal, a metal alloy, or a conductive compound. When the second electrode 6 is a transmissive electrode, the second electrode 6 may include a transparent metal oxide such as ITO, IZO, ZnO, ITZO, etc. When the second electrode 6 is a semi-transmissive semi-reflective electrode or a reflective electrode, the second electrode 6 may include Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF / Ca, LiF / Al, Mo, Ti, or a compound or mixture thereof (for example, a mixture of Ag and Mg).

[0240] The second electrode 6 may be a single layer including a single material or a single layer including a plurality of different materials. Alternatively, the second electrode 6 may have a multilayer structure including a plurality of layers containing a plurality of different materials.

[0241] The thickness of the second electrode 6 may be, but is not particularly limited to, about 10 nm to about 1,000 nm.

[0242] The second electrode 6 can be connected to an auxiliary electrode (not shown). When the second electrode 6 is connected to the auxiliary electrode, the resistance of the second electrode 6 can be reduced.

[0243] In addition, a capping layer (not shown) can be further disposed on the second electrode 6. The capping layer (not shown) is not particularly limited and can include, for example, α-NPD, NPB, TPD, m-MTDATA, Alq3, CuPc, N4,N4,N4',N4'-tetrakis(biphenyl-4-yl)biphenyl-4,4'-diamine (TPD15), 4,4',4''-tris-9-carbazolyltriphenylamine (TCTA), N,N'-bis(naphthalen-1-yl), etc.

[0244] In addition, the materials constituting each layer and each electrode can be used alone or in combinations of two or more.

[0245] In Figures 1 to 3 the organic EL device 10, the polycyclic compound or the material for the organic EL device can be included in the emission layer 4, or can be included in the organic layer other than the emission layer 4. In addition, the polycyclic compound or the material for the organic EL device can be included in the emission layer 4 and the organic layer other than the emission layer 4.

[0246] In Figures 1 to 3 the organic EL device 10, when voltages are applied to the first electrode 2 and the second electrode 6 respectively, the holes provided from the first electrode 2 can move toward the emission layer 4 through the hole transport region 3, and the electrons provided from the second electrode 6 can move toward the emission layer 4 through the electron transport region 5. The holes and electrons can recombine in the emission layer 4 to generate excitons, and the excitons can transition from the excited state to the ground state to thereby generate light.

[0247] The present disclosure includes the following aspects and embodiments.

[0248] 1. A compound having the following structure: wherein one or more polycyclic group structures represented by Formula 2 are connected to the ring Ar in the structure represented by Formula 1 1 or the ring Ar 2 , and

[0249] at least one group structure represented by Formula 3, but not more than four group structures, are added to at least one of the rings Ar in the polycyclic group structure represented by Formula 2 5 or the ring Ar 6 :

[0250]

[0251]

[0252] wherein, in Formulas 1, 2, and 3, Ar 1to Ar 8 may each independently be a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 30 ring-forming atoms, or a substituted or unsubstituted heteroaromatic ring having 5 to 30 ring-forming atoms,

[0253] In Formula 1, Z may be C or Si,

[0254] In Formula 2, X may be -O-, -S-, -NR 21 -, or -CR 22 R 23 -, where R 21 、R 22 and R 23 may each independently be hydrogen, deuterium, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group, where, if X is -NR 21 -, then R 21 may be bonded to the ring-forming atom of Ar 7 .

[0255] In Formula 2, the binding site *1 is bonded to an adjacent ring-forming atom of Ar 1 in the structure represented by Formula 1, or the binding site *1 is bonded to an adjacent ring-forming atom of Ar 2 in the structure represented by Formula 1 to form a six-membered ring, and

[0256] In Formula 3, Y may be -O-, -S- or -NR 31 -, where R 31 may be hydrogen, deuterium, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group, and the binding site *2 is bonded to two adjacent ring-forming atoms of Ar 5 in the polycyclic group structure represented by Formula 2, or the binding site *2 is bonded to an adjacent ring-forming atom of Ar 6 in the polycyclic group structure represented by Formula 2 to form a five-membered ring.

[0257] 2. The compound as described in 1., wherein the polycyclic group structure of Formula 2 is represented by Formula 4, and

[0258] at least one group structure, but not more than four group structures, each represented by Formula 5 are connected to at least one of ring Ar 5' or ring Ar 6 in the structure represented by Formula 4:

[0259]

[0260]

[0261] wherein, in Formula 4,

[0262] R 41 may be deuterium, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group,

[0263] n may be 0, 1, 2, or 3, where when n is 2 or greater, two or more Rs 41 may be the same as or different from each other, and

[0264] Ar 6 Ar, 7 X, and the binding site *1 may each be the same as those described for Formula 2,

[0265] wherein, in Formula 5,

[0266] Ar 9 may be a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 30 ring atoms, or a substituted or unsubstituted heteroaromatic ring having 5 to 30 ring atoms,

[0267] In the structure represented by Formula 5, the binding site *2 is bonded to an adjacent ring atom of Ar 5 ' or the binding site *2 is bonded to an adjacent ring atom of Ar 6 and

[0268] Ar 8 may be the same as that described in Formula 3.

[0269] 3. The compound as described in 1. or 2., including a group structure represented by Formula 6 connected to the ring Ar 1 or the ring Ar 2 in the structure represented by Formula 1:

[0270]

[0271] wherein, in Formula 6,

[0272] R 61 may be deuterium, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group,

[0273] m may be 0 or 1,

[0274] Ar 6 Ar, 7 X, and the binding site *1 are each the same as those described in Formula 2,

[0275] Ar 8 may be the same as that described in Formula 3, and

[0276] Ar 9 may be the same as that described in Formula 5.

[0277] 4. A compound as described in 1. or 2., including a group structure represented by formula 7 connected to ring Ar in the structure represented by formula 1 1 or ring Ar 2 :

[0278]

[0279] wherein, in formula 7,

[0280] R 71 and R 72 can each independently be deuterium, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group,

[0281] o can be 0, 1, 2, 3, or 4, wherein when o is 2 or greater, two or more Rs 71 can be the same as or different from each other,

[0282] p can be 0, 1, 2, or 3, wherein when p is 2 or greater, two or more Rs 72 can be the same as or different from each other,

[0283] X and the binding site *1 are as described in formula 2,

[0284] Ar 8 is as described in formula 3,

[0285] Ar 9 is as described in formula 5, and

[0286] R 61 and m are as described in formula 6.

[0287] 5. A composition comprising a compound as described in any one of 1. to 4.

[0288] 6. The composition as described in 5., further comprising at least one of a TADF material and a phosphorescent material.

[0289] 7. The composition as described in 6., wherein the phosphorescent material is a platinum complex.

[0290] 8. A material for an organic EL device, the material comprising one or more compounds as described in any one of 1. to 4.

[0291] 9. An organic EL device having an organic layer comprising one or more compounds as described in any one of 1. to 4.

[0292] 10. The organic EL device as described in 9., wherein the organic layer is an emission layer.

[0293] Examples

[0294] Hereinafter, the present disclosure will be described in more detail with reference to the following examples and comparative examples, but the technical scope of the present disclosure is not limited thereto.

[0295] Synthesis of Compound 1

[0296]

[0297] Synthesis of Intermediate 1

[0298] 3.6 g (10.83 mmol, 1.0 eq) of 2-hydroxy-9,9'-spirobi[9H-fluorene], 2.7 g (14.08 mmol, 1.3 eq) of 1-bromo-2,6-difluorobenzene, 1.5 g (10.83 mmol, 1.0 eq) of potassium carbonate and 20 mL of 1-methyl-2-pyrrolidone (NMP) were added to a reaction vessel, and the mixture was stirred under reflux in a nitrogen atmosphere for 8 hours. After completion of the reaction, the reaction solution was diluted with toluene and filtered using diatomaceous earth. The filtrate was concentrated and subjected to dispersion washing with methanol to obtain Intermediate 1 (amount: 3.94 g, yield: 72%).

[0299] Synthesis of Intermediate 2

[0300] 3.94 g (7.79 mmol, 1.05 eq) of Intermediate 1, 3.3 g (7.42 mmol, 1.0 eq) of 12-(3,5-di-tert-butylphenyl)-5,12-dihydroindolo[3,2-a]carbazole, 3.63 g (11.1 mmol, 1.5 eq) of cesium carbonate and 8 mL of dimethyl sulfoxide (DMSO) were added to a reaction vessel, and the mixture was heated and stirred at 160 °C in a nitrogen atmosphere for 24 hours. After completion of the reaction, the reaction solution was diluted with toluene and filtered using diatomaceous earth. After adding water to the filtrate, the resulting solution was separated, and the organic layer obtained therefrom was dried over magnesium sulfate and then concentrated. The concentrate was purified by column chromatography to obtain Intermediate 2 (amount: 3.0 g, yield: 43%).

[0301] Synthesis of Compound 1

[0302] 3.0 g (3.23 mmol, 1.0 eq) of Intermediate 2 and 16 mL of tert-butylbenzene were added to a reaction vessel, and the mixture was stirred. Under a nitrogen atmosphere, the reaction solution was cooled to -50 °C, and 1.8 mL (4.8 mmol, 1.5 eq) of 2.6 M n-butyllithium in hexane was added dropwise, followed by stirring for 1 hour. Then, 0.89 g (3.55 mmol, 1.1 eq) of boron tribromide was added, followed by stirring at 0 °C for 1 hour. Then, 0.84 g (2.0 eq, 6.45 mmol) of N,N-diisopropylethylamine was added, followed by heating and stirring at 150 °C for 12 hours. After the reaction was completed, the reaction solution was cooled to room temperature, and the organic layer was extracted with water and dichloromethane. The organic layer was separated and dried over magnesium sulfate, and then concentrated. The concentrate was purified by silica gel column chromatography to obtain Compound 1 (amount: 0.77 g, yield: 27%).

[0303] The structural confirmation of Compound 1 was performed using liquid chromatography-mass spectrometry (LC-MS). Specifically, the sample (Compound 1) was dissolved in tetrahydrofuran at a concentration of 0.1 wt%, and mass spectrometry was performed using an LC-MS measuring device 1260 Infinity - quadruple electrode 6100 MS (manufactured by Agilent Technology Co., Ltd.). The obtained result value: LC-MS: 859 ([M+H] + )

[0304] Synthesis of Compound 2

[0305]

[0306] Synthesis of Intermediate 3

[0307] Intermediate 3 was prepared in the same manner as in the synthesis of Intermediate 1, except that 1-bromo-2,6-difluorobenzene was changed to 4'-bromo-3',5'-difluoro-3,5-di-tert-butyl-1,1'-biphenyl (amount: 10.5 g, yield: 59%).

[0308] Synthesis of Intermediate 4

[0309] Intermediate 4 was prepared in the same manner as in the synthesis of Intermediate 2, except that Intermediate 1 was changed to Intermediate 3 (amount: 6.8 g, yield: 42%).

[0310] Synthesis of Compound 2

[0311] Compound 2 was prepared in the same manner as in the synthesis of Compound 1 (amount: 0.8 g, yield: 12%) except that Intermediate 2 was changed to Intermediate 4. The structure of Compound 2 was confirmed in the same manner as that of Compound 1: LC-MS: 1048 ([M+H] + )

[0312] Synthesis of Compound 3

[0313]

[0314] Synthesis of Intermediate 5

[0315] Intermediate 5 was prepared in the same manner as in the synthesis of Intermediate 1 (amount: 9.5 g, yield: 54%) except that 2-hydroxy-9,9'-spirobi[9H-fluorene] was changed to 1-hydroxy-9,9'-spirobi[9H-fluorene] and 1-bromo-2,6-difluorobenzene was changed to 4'-bromo-3',5'-difluoro-3,5-di-tert-butyl-1,1'-biphenyl).

[0316] Synthesis of Intermediate 6

[0317] Intermediate 6 was prepared in the same manner as in the synthesis of Intermediate 2 (amount: 7.8 g, yield: 50%) except that Intermediate 1 was changed to Intermediate 5.

[0318] Synthesis of Compound 3

[0319] Compound 3 was prepared in the same manner as in the synthesis of Compound 1 (amount: 1.0 g, yield: 20%) except that Intermediate 2 was changed to Intermediate 6.

[0320] The structure of Compound 3 was confirmed in the same manner as that of Compound 1: LC-MS: 1048 ([M+H] + )

[0321] Synthesis of Compound 4

[0322]

[0323] Synthesis of Intermediate 7

[0324] 15.0 g (29.7 mmol, 1.0 eq) of Intermediate 1, 9.1 g (35.6 mmol, 1.2 eq) of 5,12-dihydroindolo[3,2-a]carbazole, 14.5 g (44.5 mmol, 1.5 eq) of cesium carbonate, and 30 mL of dimethyl sulfoxide were added to a reaction vessel, and the mixture was heated and stirred at 160 °C for 30 h under a nitrogen atmosphere. After completion of the reaction, the reaction solution was diluted with toluene and filtered through diatomaceous earth. Water was added to the filtrate to extract the organic layer, and the separated organic layer was dried over magnesium sulfate and concentrated. The concentrate was purified by silica gel column chromatography to obtain Intermediate 7 (amount: 10.0 g, yield: 45%).

[0325] Synthesis of Intermediate 8

[0326] 5.0 g (6.7 mmol, 1.0 eq) of Intermediate 7, 3.4 g (8.8 mmol, 1.3 eq) of 3,5-di-tert-butyl-4'-iodo-1,1'-biphenyl, 2.8 g (20.2 mmol, 3.0 eq) of potassium carbonate, 0.214 mg (3.37 mmol, 0.5 eq) of copper powder, and 7 mL of o-dichlorobenzene were added to a reaction vessel, and the mixture was stirred under reflux for 24 h under a nitrogen atmosphere. After completion of the reaction, the reaction solution was diluted with toluene and filtered through diatomaceous earth. The filtrate was concentrated and purified by silica gel column chromatography to obtain Intermediate 8 (amount: 6.2 g, yield: 92%).

[0327] Synthesis of Compound 4

[0328] 2.0 g (3.28 mmol, 1.0 eq) of Intermediate 8 and 2.5 mol of tert-butylbenzene were added to a reaction vessel, and the mixture was stirred. Under a nitrogen atmosphere, the reaction solution was cooled to -50 °C, 0.7 ml (1.1 mmol, 2.2 eq) of 1.6 M tert-butyllithium pentane solution was added dropwise, and then the mixture was stirred at room temperature (25 °C) for 1 h. Substances with low boiling points were removed by distillation. The resulting solution was cooled to 0 °C, 0.05 ml (0.6 mmol, 1.1 eq) of boron tribromide was added, and then the mixture was stirred at room temperature (25 °C) for 1 h. Then, 0.17 ml (1.0 mmol, 2.0 eq) of N,N-diisopropylethylamine was added, and then the mixture was heated and stirred at 150 °C for 20 h. After completion of the reaction, the reaction solution was cooled to room temperature, and the organic layer was extracted with water and toluene. The organic layer was separated, dried over magnesium sulfate, and concentrated. The concentrate was purified by silica gel column chromatography to obtain Compound 4 (amount: 0.13 g, yield: 28%). The structure of Compound 4 was confirmed in the same manner as that of Compound 1: LC-MS: 936 ([M+H] + )

[0329] Simulation evaluation of fused-ring compounds

[0330] According to Seob Park et al. in "High-Performance Dibenzoheteraborin-Based Thermally Activated Delayed Fluorescence Emitters: Molecular Architectonics for Concurrently Achieving Narrowband Emission and Efficient Triplet-Singlet Spin Conversion" in Advanced Functional Materials 2018, 28, 1802031, the spectral width of fluorescence (FWHM of the fluorescence spectral peak) is closely related to the reorganization energy [E(S0@S1) - E(S0@S0)], and the reorganization energy is represented by the difference between the ground state (S0) energy [E(S0@S1)] of the stable structure in the first excited singlet state (S1) and the ground state (S0) energy [E(S0@S0)] of the stable structure in the ground state (S0).

[0331] Calculation of the oscillator strength f, reorganization energy, and fluorescence wavelength of the compounds disclosed and the comparative compound R1

[0332] For the compounds described herein and the cyclic compound R1 (comparative compound 1) known in the art, the following calculations are performed according to DFT. Calculate the oscillator strength f, reorganization energy, and fluorescence wavelength of Compounds 1 to 3 and comparative compound 1.

[0333]

[0334] Calculate the ground state (S0) energy [E(S0@S1)] of the stable structure in the first excited singlet state (S1) and the ground state (S0) energy [E(S0@S0)] of the stable structure in the ground state (S0), and calculate the reorganization energy [E(S0@S1)] - [E(S0@S0)] (eV) from the difference therebetween.

[0335] In addition, calculate the first excited singlet state (S1) energy [E(S1@S1)] of the stable structure in the first excited singlet state (S1), and calculate the adiabatic first excited singlet state (S1) energy [E(S1@S1)] - [E(S0@S0)] (eV) from the difference between this value and the ground state (S0) energy [E(S0@S0)] of the stable structure in the ground state (S0).

[0336] Determine the fluorescence wavelength (nm) obtained by converting the energy of the adiabatic first excited singlet state (S1) into a light wavelength (nm). Additionally, determine the oscillator strength f of the stable structure in the first excited singlet state (S1).

[0337] Perform DFT calculations using Gaussian 16 (Gaussian Inc.) as the calculation software according to the following calculation methods (I), (II), and (III):

[0338] (I) S0 calculation method: Structural optimization calculation by DFT including the functional B3LYP, basis function 6-31G(d,p), and toluene solvent effect (polarizable continuum model (PCM));

[0339] (II) S1 calculation method: Structural optimization calculation by time-dependent DFT (TDDFT) including the functional B3LYP, basis function 6-31G(d,p), and toluene solvent effect (PCM); and

[0340] (III) S0 calculation method: Calculate the input structure by DFT including the functional B3LYP, basis function 6-31G(d,p), and toluene solvent effect (PCM).

[0341] Specifically, perform the calculations for each item using the following calculation methods:

[0342] Ground state (S0) energy [E(S0@S0)] of the stable structure in the ground state (S0): Calculation method (I);

[0343] First excited singlet state (S1) energy [E(S1@S1)] of the stable structure in the first excited singlet state (S1): Calculation method (II);

[0344] Ground state (S0) energy [E(S0@S1)] of the stable structure in the first excited singlet state (S1): Calculation methods (II) and (III);

[0345] Reorganization energy [E(S0@S1)] - [E(S0@S0)]: Calculation methods (I), (II), and (III);

[0346] Adiabatic first excited singlet state (S1) energy [E(S1@S1)] - [E(S0@S0)]: Calculation methods (I) and (II);

[0347] Fluorescence wavelength (nm): Calculation methods (I) and (II); and

[0348] Oscillator strength f of the stable structure in the first excited singlet state (S1): Calculation method (II).

[0349] Figure 4 It is an explanatory diagram qualitatively showing each energy relationship. The calculation results are shown in Table 1.

[0350] Table 1

[0351]

[0352]

[0353]

[0354]

[0355] As shown in Table 1, the maximum reorganization energy value of the polycyclic compounds listed in Table 1 is 0.11 eV (for example, see Compounds 8, 18, 28, 37, 43, 44, and 76, each of which has the same calculated value as Comparative Compound 1). However, most of the polycyclic compounds in Table 1 each have a calculated reorganization energy value smaller than that of Comparative Compound 1.

[0356] Therefore, those of ordinary skill in the art would expect that the polycyclic compounds described herein would have an FWHM equal to or less than that of Comparative Compound 1, and thus, each compound would have a color purity equal to or higher than that of Comparative Compound 1.

[0357] In addition, it was confirmed that each of the polycyclic compounds has a sufficiently large oscillator strength f and excellent fluorescence efficiency.

[0358] From the above results, it was confirmed that, compared with Comparative Compound 1, each of the compounds has a small reorganization energy, a large oscillator strength f, and a suitable blue fluorescence wavelength. Therefore, it was confirmed that each of the compounds has a narrow emission spectral width and thus can each be used as a blue light-emitting material capable of achieving high color purity of an organic EL device and improving the light-emitting efficiency of the organic EL device.

[0359] Evaluation of Compounds

[0360] Method for Preparing a Thin Film

[0361] Compounds 1 to 3 or Comparative Compound 1 were co-deposited on a quartz substrate at a vacuum pressure of 10 -5 Pa at a weight ratio relative to the weight percentage of the host compound 1 to prepare a thin film having a thickness of 50 nm (hereinafter, also referred to as "host-dispersed film"). Compounds HT1 and HT2 were used as host compounds and Pt1 was used as a phosphorescent complex, and the weight ratio of Compound HT1:Compound HT2:phosphorescent complex Pt1 was 60:40:13. In addition, the structures of Compounds HT1 and HT2 and the phosphorescent complex Pt1 are as follows.

[0362]

[0363] Measurement of PL (FWHM)

[0364] The above-prepared thin film (host-dispersed film) was cut into strips having a width of 6 nm, and PL measurement was carried out at room temperature using a spectrofluorometer F-7000 manufactured by Hitachi High-Tech Co., Ltd. From the obtained emission spectrum, the peak wavelength (maximum emission wavelength) and the spectral width (FWHM) were determined. The evaluation results are shown in Table 2.

[0365] Measurement of PL quantum yield (PLQY)

[0366] For the above-prepared thin film (host-dispersed film), the PLQY was measured using an absolute PLQY measurement device C11347-01, Quantaurus-QY, manufactured by Hamamatsu Photonics Co., Ltd. In the measurement, the excitation wavelength was scanned at intervals of 10 nm from 280 nm to 350 nm, and the excitation wavelength region in which the absorption value of the compound showed an excitation light intensity ratio of 20% or more was adopted. The value of PLQY was the highest value in the adopted excitation wavelength region. The evaluation results are shown in Table 2.

[0367] Table 2

[0368]

[0369]

[0370] It was confirmed from the results of Table 2 that Compounds 1, 2, and 3 each exhibited a narrow emission spectrum with a blue wavelength as the peak wavelength. Moreover, Compounds 1, 2, and 3 each exhibited a lower FWHM than Comparative Compound 1 and thus achieved blue luminescence with high color purity. In addition, it was confirmed that Compounds 1, 2, and 3 each exhibited a higher PLQY than Comparative Compound 1.

[0371] Fabrication of organic EL device

[0372] Device Fabrication Example 1

[0373] The ITO glass substrate on which the electrode pattern was formed was cut into a size of 50 mm × 50 mm × 0.7 mm, ultrasonically treated in acetone, isopropyl alcohol, and pure water in the stated order for 15 minutes each, and then cleaned by exposure to UV ozone for 30 minutes. The following layers were deposited on the ITO electrode (anode) of the glass substrate using a vacuum deposition device.

[0374] First, deposit HAT-CN (see the following formula) on the ITO electrode to form a hole injection layer with a thickness of 10 nm. Deposit compound HT3 (see the following formula) on the hole injection layer to form a hole transport layer with a thickness of 140 nm. Deposit compound HT1 (see the following formula) on the hole transport layer to form an electron blocking layer with a thickness of 5 nm. As a result, a hole transport region is formed.

[0375] Co-deposit compound HT1, compound HT2, phosphorescent complex Pt1 (see the following formula), and the obtained compound 1 above on the formed hole transport region to form an emission layer with a thickness of 40 nm. The emission layer is formed such that the weight ratio of compound HT1, compound HT2, and phosphorescent complex Pt1 in the emission layer is compound HT1: compound HT2: phosphorescent complex Pt1 = 60:40:13. Additionally, the emission layer is formed such that, based on the total weight of compound HT1, compound HT2, phosphorescent complex Pt1, and compound 1 (i.e., the total weight of the emission layer), the concentration of compound 1 is 1.0 wt%. Additionally, compounds HT1 and HT2 are host materials.

[0376] Vacuum deposit compound HT2 on the obtained emission layer above to form a hole blocking layer with a thickness of 5 nm. Co-deposit compound H91 and LiQ in a weight ratio of compound H91:LiQ = 5:5 (unit: parts by weight) on the hole blocking layer to form an electron transport layer with a thickness of 30 nm. Deposit LiQ on the electron transport layer to form an electron injection layer with a thickness of 1 nm. As a result, an electron transport region is formed.

[0377] Deposit Al (cathode) on the electron injection layer to a thickness of 100 nm to thereby fabricate organic EL device 1.

[0378] In a glove box with a nitrogen atmosphere having a moisture concentration of 1 ppm or less and an oxygen concentration of 1 ppm or less, seal the fabricated organic EL device 1 above using a glass seal tube (manufactured by MORESCO Co., Ltd., product name WB90US) having a desiccant and an ultraviolet curable resin.

[0379]

[0380] Device Fabrication Example 2

[0381] Fabricate organic EL device 2 in the same manner as in Device Fabrication Example 1, except as follows: Use compound 2 instead of compound 1 in the formation of the emission layer. Seal the device as described above to complete the fabrication of organic EL device 2.

[0382] Device Fabrication Example 3

[0383] An organic EL device 3 was fabricated in the same manner as in Device Fabrication Example 1, except that Compound 3 was used instead of Compound 1 in the formation of the emission layer. The device was sealed as described above to complete the fabrication of the organic EL device 3.

[0384] Device Fabrication Comparative Example 1

[0385] A comparative organic EL device 1 was fabricated in the same manner as in Device Fabrication Example 1, except that Comparative Compound 1 was used instead of Compound 1 in the formation of the emission layer. The device was sealed as described above to complete the fabrication of the comparative organic EL device 1.

[0386] Evaluation of Organic EL Devices

[0387] Luminance, External Quantum Efficiency (EQE), and Device Lifetime

[0388] The emission peak wavelength, emission spectral width, EQE, and device lifetime were evaluated at a luminance of 1,000 candela per square meter (cd / m 2 ) according to the following method.

[0389] While changing the voltage applied to the device using a DC constant voltage power supply (source meter 2400 manufactured by KEITHLEY), the organic EL device was allowed to emit light, and the luminance, emission spectrum, and luminous flux at this time were measured using a luminance meter (SR-3 manufactured by Topcon).

[0390] The EQE was calculated from the emission spectrum, luminance, and current value at the time of measurement. The EQE at a luminance of 1,000 cd / m 2 is defined as EQE [%].

[0391] In addition, the device lifetime (durability) was defined as LT 95 and was obtained by measuring the amount of time it took for the emission luminance to decay to 95% of the initial luminance when the device was driven at a current value with an initial luminance of 1,000 cd / m 2 . In addition, LT in Table 3 95 is a relative (normalized) value and corresponds to setting the LT 95 (unit: hr) of the comparative organic EL device 1 to 1.

[0392] Emission Peak Wavelength and Emission Spectral Width (FWHM, FWQM)

[0393] The luminescence peak wavelength and the emission spectrum width are obtained by measuring the emission spectrum. The wavelength representing the maximum intensity value of the emission spectrum is defined as the emission peak wavelength, the wavelength width corresponding to half of the maximum intensity value is defined as the FWHM, and the wavelength width corresponding to 1 / 4 (one quarter) of the maximum intensity value is defined as the FWQM.

[0394] In addition, in this evaluation, the luminescence peak wavelength is not particularly limited, but it can be within the blue emission region and can be 455 nm to 475 nm, or for example, 455 nm to 465 nm.

[0395] In this evaluation, the emission spectrum width (FWHM and FWQM) can be small, and it is generally accepted by those skilled in the art that the smaller the emission spectrum width, the higher the color purity. The evaluation results of each organic EL device are shown in Table 3.

[0396] Table 3

[0397]

[0398]

[0399] From the results in Table 3, it can be confirmed that compared with Comparative Organic EL Device 1, Organic EL Devices 1, 2, and 3 using Compounds 1, 2, and 3 respectively each exhibit blue luminescence with reduced FWHM and FWQM, that is, a narrower peak emission, and thus, relatively high color purity. In addition, it is confirmed that since Compounds 1, 2, and 3 each exhibit relatively larger EQE, Organic EL Devices 1 and 2 each have excellent luminous efficiency and device lifetime. In particular, it is confirmed that Organic EL Device 2 having Compound 2 has an EQE improved to 1.3 times that of Comparative Organic EL Device 1 and a lifetime improved to 4 times that of Comparative Organic EL Device 1.

[0400] By using the compounds described and claimed herein as the luminescent material, compared with devices of similar designs that use only known luminescent materials, blue EL devices with narrower peak emission, higher efficiency, and longer lifetime can be achieved. For example, devices with an emission wavelength of 465 nm or less, relatively high color purity, larger EQE, and / or larger device lifetime can be obtained.

[0401] It should be understood that the embodiments described herein should be considered only in a descriptive sense and not for purposes of limitation. The description of features or aspects in each embodiment should typically be considered applicable to other similar features or aspects in other embodiments. Although one or more embodiments have been described with reference to the accompanying drawings, those of ordinary skill in the art will understand that various changes in form and detail can be made therein without departing from the spirit and scope as defined by the appended claims.

Claims

1. A compound, comprising: Ring Ar of the structure represented by Formula 1 1 or ring Ar 2 a polycyclic group structure represented by Formula 2 which is connected to at least one of them; and Ring Ar of the polycyclic group structure represented by formula 2 5 or ring Ar 6 each of at least one group structure represented by formula 3, but not more than four group structures, connected to Wherein, in Formulas 1, 2, and 3, Ar 1 to Ar 8 each independently is a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 30 ring-forming atoms, or a substituted or unsubstituted heteroaromatic ring having 5 to 30 ring-forming atoms In Formula 1, Z is C or Si, In Formula 2, X is -O-, -S-, -NR 21 -, or -CR 22 R 23 -, R 21 、R 22 and R 23 each independently represents hydrogen, deuterium, substituted or unsubstituted alkyl, substituted or unsubstituted aryl, or substituted or unsubstituted heteroaryl, wherein if X is -NR 21 -, then R 21 is bonded to the ring-forming atom of Ar 7 and The binding site *1 is bonded to the adjacent ring-forming atoms in Ar in the structure represented by Formula 1, or the binding site *1 is bonded to the adjacent ring-forming atoms in Ar 1 in the structure represented by Formula 1 to form a six-membered ring, and 2 the adjacent ring-forming atoms in the structure represented by Formula 1 are bonded to form a six-membered ring, and In Formula 3, Y is -O-, -S-, or -NR 31 -, R 31 is hydrogen, deuterium, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group, and The binding site *2 is bonded to adjacent ring-forming atoms in the polycyclic group structure represented by Formula 2, or the binding site *2 is bonded to adjacent ring-forming atoms in the polycyclic group structure represented by Formula 2 5 to form a five-membered ring. 6 to form a five-membered ring.

2. The compound according to claim 1, wherein the group structure represented by formula 3 is linked to ring Ar 5 , and X is O or -NR 21 -.

3. The compound according to claim 1, wherein In Formula 1, Ar 1 to Ar 4 are each independently selected from: Each unsubstituted benzene ring, cyclopentadiene ring, indene ring, naphthalene ring, anthracene ring, azulene ring, heptalene ring, acenaphthene ring, phenalene ring, fluorene ring, phenanthrene ring, biphenyl ring, terphenyl ring, benzo[9,10]phenanthrene ring, pyrene ring, coronene ring, picene ring, perylene ring, pentaphene ring, pentacene ring, benzo[a]anthracene ring, hexaphene ring, hexacene ring, rubicene ring, terrylene ring, heptaphene ring, or picene ring; and A benzene ring, a cyclopentadiene ring, an indene ring, a naphthalene ring, an anthracene ring, an azulene ring, a heptalene ring, an acenaphthene ring, a phenalene ring, a fluorene ring, a phenanthrene ring, a biphenyl ring, a terphenyl ring, a benzo[9,10]phenanthrene ring, a pyrene ring, each of which is substituted as follows, a chrysene ring, a perylene ring, a pentaphene ring, a pentacene ring, a benzo[a]anthracene ring, a hexaphene ring, a hexacene ring, a rubicene ring, a terrylene ring, a heptaphene ring, or a picene ring: a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryloxy group, a substituted or unsubstituted heteroaryloxy group, a substituted or unsubstituted diarylamino group, a substituted or unsubstituted diheteroarylamino group, a substituted or unsubstituted arylheteroarylamino group, or a combination thereof, wherein the substituents of the substituted alkyl, substituted aryl, substituted heteroaryl, substituted alkoxy, substituted aryloxy, substituted heteroaryloxy, substituted diarylamino, substituted diheteroarylamino, and substituted arylheteroarylamino are each independently selected from a deuterium atom, a halogen atom, an unsubstituted alkyl, an unsubstituted aryl, an unsubstituted heteroaryl, an unsubstituted alkoxy, an unsubstituted aryloxy, an unsubstituted heteroaryloxy, an unsubstituted diarylamino, an unsubstituted diheteroarylamino, an unsubstituted arylheteroarylamino, or a combination thereof.

4. The compound according to claim 3, wherein In Formula 1, Ar 1 and Ar 2 are each independently selected from: A benzene ring; and A benzene ring substituted with: a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl, a substituted or unsubstituted aryl, a substituted or unsubstituted heteroaryl, a substituted or unsubstituted alkoxy, a substituted or unsubstituted aryloxy, a substituted or unsubstituted heteroaryloxy, a substituted or unsubstituted diarylamino, a substituted or unsubstituted diheteroarylamino, a substituted or unsubstituted arylheteroarylamino, or a combination thereof, wherein the substituents of the substituted alkyl, substituted aryl, substituted heteroaryl, substituted alkoxy, substituted aryloxy, substituted heteroaryloxy, substituted diarylamino, substituted diheteroarylamino, and substituted arylheteroarylamino are each independently selected from a deuterium atom, a halogen atom, an unsubstituted alkyl, an unsubstituted aryl, an unsubstituted heteroaryl, an unsubstituted alkoxy, an unsubstituted aryloxy, an unsubstituted heteroaryloxy, an unsubstituted diarylamino, an unsubstituted diheteroarylamino, an unsubstituted arylheteroarylamino, or a combination thereof.

5. The compound according to claim 1, wherein the structure of Formula 1 is represented by one of Formulas 1-1 to 1-6: Among them, In Formulas 1-1 to 1-6, R 11 and R 12 each independently is deuterium, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group, q and t are each independently 0, 1 or 2, where when q is 2, two Rs 11 are the same as or different from each other, and when t is 2, two Rs 12 are the same as or different from each other, s and r are each independently 0, 1, 2, 3, or 4, where when s is 2 or greater, two or more of the Rs 12 are the same as or different from each other, and when r is 2 or greater, two or more of the Rs 11 are the same as or different from each other, *3 represents an adjacent ring-forming carbon atom connected to the binding site *1 in the polycyclic group structure represented by Formula 2, and Ar 3 、Ar 4 and Z are each as described in Formula 1.

6. The compound according to claim 1, wherein the polycyclic group structure of Formula 2 is represented by Formula 4, and At least one, but no more than four, group structures each represented by Freestyle 5 are attached to ring Ar in the structure represented by Formula 4 5 ' or ring Ar 6 of at least one: Among them, In Formula 4, R 41 is deuterium, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group, n is 0, 1, 2 or 3, where when n is 2 or greater, two or more Rs 41 are the same as or different from each other, and Ar 6 、 Ar 7 , X and binding site *1 are each as described in Formula 2, Wherein, in Formula 5, Ar 9 is a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 30 ring-forming atoms, or a substituted or unsubstituted heteroaromatic ring having 5 to 30 ring-forming atoms. In the structure represented by Formula 5, the binding site *2 is bonded to an adjacent ring-forming atom of Ar 5 ', or the binding site *2 is bonded to an adjacent ring-forming atom of Ar 6 , and Ar 8 As described in Formula 3.

7. The compound according to claim 6, comprising a group structure represented by Formula 6 linked to ring Ar in the structure represented by Formula 1 1 or ring Ar 2 : Formula 6 Among them, In Formula 6, R 61 is deuterium, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group, m is 0 or 1, Ar 6 、Ar 7 , X, and binding site *1 are each as described in Formula 2, Ar 8 as described in formula 3, and Ar 9 As described in Formula 5.

8. The compound according to claim 7, comprising a group structure represented by formula 7 linked to ring Ar in the structure represented by formula 1 1 or ring Ar 2 : Formula 7 Among them, In Formula 7, R 71 and R 72 each independently is deuterium, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group, o is 0, 1, 2, 3 or 4, where when o is 2 or greater, two or more Rs 71 are the same as or different from each other, p is 0, 1, 2 or 3, where when p is 2 or greater, two or more Rs 72 are the same as or different from each other, X and the binding site *1 are as described in Formula 2, Ar 8 As described in formula 3, Ar 9 as described in formula 5, and R 61 and m are as described in Equation 6.

9. The compound according to claim 1, wherein In Formula 2, X is -O- or -S-.

10. The compound according to claim 1 and any one of claims 4 to 8, wherein the substituents of the substituted alkyl, substituted aryl, and substituted heteroaryl are each independently selected from: A deuterium atom, a halogen atom, an alkyl, an aryl, a heteroaryl, an alkoxy, an aryloxy, a heteroaryloxy, a diarylamino, a diheteroarylamino, and an arylheteroarylamino; and An alkyl, an aryl, a heteroaryl, an alkoxy, an aryloxy, a heteroaryloxy, a diarylamino, a diheteroarylamino, and an arylheteroarylamino each substituted with: a deuterium atom, a halogen atom, an alkyl, an aryl, a heteroaryl, an alkoxy, an aryloxy, a heteroaryloxy, a diarylamino, a diheteroarylamino, an arylheteroarylamino, or a combination thereof.

11. The compound according to claim 1, represented by one of Compounds 1 to 109:

12. The compound according to claim 1, having a peak emission wavelength in the blue region.

13. Materials for organic electroluminescent devices, said materials comprising one or more compounds according to any one of claims 1 to 12.

14. The material according to claim 13, further comprising at least one of a thermally activated delayed fluorescence material and a phosphorescent material.

15. The material according to claim 14, wherein the phosphorescent material is a platinum complex.

16. The material according to claim 14, further comprising a host material.

17. An organic electroluminescent device having an organic layer comprising one or more compounds according to any one of claims 1 to 12.

18. The organic electroluminescent device according to claim 17, wherein the organic layer comprises an emission layer, and the emission layer comprises the one or more compounds.

19. The organic electroluminescent device according to claim 18, wherein the emission layer comprises a host material and a dopant material, and the dopant material comprises the one or more compounds.

20. The organic electroluminescent device according to claim 19, wherein the emission layer further comprises at least one of a thermally activated delayed fluorescence material and a phosphorescent material.

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