Organic electroluminescent device

Abstract

An organic electroluminescent device according to an embodiment of the present disclosure includes a first electrode, a second electrode, and a light-emitting layer. The light-emitting layer includes a host compound and a dopant compound. The host compound includes a first host compound represented by Formula 1 and a second host compound represented by Formula 2, and the dopant compound includes a co-dopant compound represented by Formula 3 and a light-emitting dopant compound represented by Formula 4. Accordingly, the organic electroluminescent device according to the embodiment can achieve high efficiency and long lifespan.

Description

[0001] Cross - reference to related applications

[0002] This application claims the priority and benefit of Korean Patent Application No. 10 - 2019 - 0121814, filed on October 1, 2019, the entire content of which is incorporated herein by reference. Technical field

[0003] One or more aspects of the embodiments disclosed herein relate to an organic electroluminescent device. Background art

[0004] As an image display device, the development of an organic electroluminescent device is actively underway. An organic electroluminescent device is a self - emitting display device, in which holes and electrons injected from a first electrode and a second electrode recombine in a light - emitting layer, and a light - emitting material, which is an organic compound included in the light - emitting layer, emits light.

[0005] As an organic electroluminescent device, for example, an organic device may be composed of a first electrode, a hole - transporting layer on the first electrode, a light - emitting layer on the hole - transporting layer, an electron - transporting layer on the light - emitting layer, and a second electrode on the electron - transporting layer. Holes are injected from the first electrode, and the injected holes pass through the hole - transporting layer and are injected into the light - emitting layer. At the same time, electrons are injected from the second electrode, and the injected electrons pass through the electron - transporting layer and are injected into the light - emitting layer. By the recombination of holes and electrons injected into the light - emitting layer, excitons are generated in the light - emitting layer. The organic electroluminescent device emits light using the light generated by the excitons transitioning back to the ground state.

[0006] When applying an organic electroluminescent device to a display device, an increase in the lifespan and efficiency of the organic electroluminescent device is required (or desired). Summary of the invention

[0007] One or more aspects of the embodiments of the present disclosure are directed to an organic electroluminescent device having high efficiency and a long lifespan.

[0008] An organic electroluminescent device according to an embodiment of the present disclosure may include a first electrode, a second electrode on the first electrode, and a light - emitting layer between the first electrode and the second electrode. The light - emitting layer may include a host compound and a dopant compound. The host compound may include a first host compound represented by Formula 1 and a second host compound represented by Formula 2. The dopant compound may include an auxiliary dopant compound represented by Formula 3 and a light - emitting dopant compound represented by Formula 4:

[0009]

[0010] Formula 3

[0011]

[0012] Formula 4

[0013]

[0014] In Formula 1, R1 and R2 can each independently be a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 30 ring carbon atoms. L1 can be a substituted or unsubstituted arylene group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroarylene group having 3 to 30 ring carbon atoms. Ar1 can be a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 30 ring carbon atoms. "a" and "b" can each independently be an integer from 0 to 4.

[0015] In Formula 2, Z1 to Z3 can each independently be CR 11 or N. One or more R 11 and multiple R 12 can each independently be a hydrogen atom, a deuterium atom, a cyano group, a substituted silyl group, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 30 ring carbon atoms.

[0016] In Formula 3, A1 to A4 can each independently be a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 1 to 30 ring carbon atoms. X1 to X4 can each independently be C or N. R 21 to R 24 can each independently be a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a substituted or unsubstituted amino group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 1 to 30 ring carbon atoms, and any one of R 21 to R 24 can optionally combine with an adjacent group to form a ring. d1 to d4 can each independently be an integer from 0 to 4. L 21 to L 23 can each independently be a direct bond, *-O-*, *-S-*, a substituted or unsubstituted divalent alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted arylene group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroarylene group having 2 to 30 ring carbon atoms. R 25 to R 27 can each independently be a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 30 ring carbon atoms, and R 25 to R27 Any one of them can combine with adjacent groups to form a ring. d5 can be an integer from 0 to 8. M can be platinum, palladium, copper, osmium, iridium, rubidium or rhodium. e1 to e3 can each independently be 0 or 1. "m" can be 1 or 2. When M is platinum, palladium, copper or osmium, "m" can be 1. When M is iridium, rubidium or rhodium, "m" can be 2, and e2 can be 0.

[0017] In Formula 4, R 31 to R 41 can each independently be a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted silyl group, a substituted or unsubstituted amino group, a substituted or unsubstituted carbonyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 30 ring carbon atoms.

[0018] In an embodiment, L1 can be a substituted or unsubstituted phenylene group, a substituted or unsubstituted divalent biphenyl group, or a substituted or unsubstituted carbazolylene group.

[0019] In an embodiment, Ar1 can be a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted dibenzofuranyl group, a substituted or unsubstituted dibenzothiophenyl group, or a substituted or unsubstituted biphenyl group.

[0020] In an embodiment, Formula 2 can be represented by the following Formula 2-1:

[0021] Formula 2-1

[0022]

[0023] In Formula 2-1, multiple R 12 can each independently be a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 30 ring carbon atoms.

[0024] In an embodiment, Formula 2 can be represented by the following Formula 2-2:

[0025] Formula 2-2

[0026]

[0027] In Formula 2-2, one or more R 11 and multiple R 12 can each independently be a hydrogen atom, a deuterium atom, a cyano group, a substituted silyl group, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 30 ring carbon atoms. Multiple R11 and multiple Rs 12 At least one of them can be a cyano group, an aryl group having 6 to 30 ring-forming carbon atoms containing at least one cyano group as a substituent, or a heteroaryl group having 3 to 20 ring-forming carbon atoms containing at least one cyano group as a substituent.

[0028] In an embodiment, Formula 3 can be represented by the following Formula 3-1:

[0029] Formula 3-1

[0030]

[0031] In Formula 3-1, A1 to A4, X1 to X4, R 21 to R 24 , d1 to d4, and L 22 can be the same as those defined in Formula 3.

[0032] In an embodiment, A1 to A4 can each independently be represented by any one of the following Structures 1-1 to 1-3.

[0033]

[0034] In Structures 1-1 to 1-3, Y1 can be C-* or CR 54 , Y2 can be N-* or NR 61 , Y3 can be N-* or NR 62 . R 51 to R 64 can each independently be a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 6 to 30 ring-forming carbon atoms, and any one of R 51 to R 64 can combine with an adjacent group to form a ring.

[0035] In an embodiment, Formula 3 can be represented by the following Formula 3-2:

[0036] Formula 3-2

[0037]

[0038] In Formula 3-2, A1 to A4, X1 to X4, R 21 to R 24 , and d1 to d4 can be the same as those defined in Formula 3.

[0039] In an embodiment, A1 to A4 can each independently be represented by the following Structure 2-1 or 2-2:

[0040]

[0041] In structure 2-1, Y 11 and Y 12 can each independently be C or N. Y 13 to Y 16 can each independently be N or CR 71 One or more R 71 can each independently be a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a substituted or unsubstituted amino group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 1 to 30 ring carbon atoms, and R 71 can optionally combine with an adjacent group to form a ring.

[0042] In structure 2-2, Y 17 and Y 18 can each independently be N or CR 72 R 72 and R 73 can each independently be a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a substituted or unsubstituted amino group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 1 to 30 ring carbon atoms, and any one of R 72 and R 73 can combine with an adjacent group to form a ring.

[0043] In an embodiment, formula 4 can be represented by the following formula 4-1:

[0044] Formula 4-1

[0045]

[0046] In formula 4-1, R 32 、R 33 、R 36 、R 37 and R 40 can each independently be a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted silyl group, a substituted or unsubstituted amino group, a substituted or unsubstituted carbonyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 30 ring carbon atoms. At least one of R 32 、R 33 、R 36 、R 37 and R 40 may not be a hydrogen atom.

[0047] In an embodiment, the light-emitting layer may emit blue light as delayed fluorescence.

[0048] In an embodiment, based on the total weight of the first host compound, the second host compound, the auxiliary dopant compound, and the light-emitting dopant compound, the amount of the auxiliary dopant compound may be from about 10 wt% to about 15 wt%, and the amount of the light-emitting dopant compound may be from about 1 wt% to about 5 wt%.

[0049] In an embodiment, based on the total weight of the host compound, the weight ratio of the first host compound to the second host compound may be from about 7:3 to about 3:7.

[0050] In an embodiment, the first host compound may include at least one of the compounds represented in the following Compound Group 1:

[0051] Compound Group 1

[0052]

[0053]

[0054] In an embodiment, the second host compound may include at least one of the compounds represented in the following Compound Group 2-1:

[0055] Compound Group 2-1

[0056]

[0057]

[0058] In an embodiment, the second host compound may include at least one of the compounds represented in the following Compound Group 2-2:

[0059] Compound Group 2-2

[0060]

[0061]

[0062] In an embodiment, the auxiliary dopant compound may include at least one of the compounds represented in the following Compound Group 3-1:

[0063] Compound Group 3-1

[0064]

[0065]

[0066] In an embodiment, the auxiliary doping compound may include at least one of the compounds represented in Compound Group 3-2 below:

[0067] Compound Group 3-2

[0068]

[0069] In Compounds D2-1 to D2-4, D2-13 to D2-16, and D2-25 to D2-28, one or more Rs may each independently be a hydrogen atom, a methyl group, an isopropyl group, a tert-butyl group, or a dimethylamino group.

[0070] In an embodiment, the luminescent doping compound may include at least one of the compounds represented in Compound Group 4 and Formula 4-2 below:

[0071] Compound Group 4

[0072]

[0073]

[0074]

[0075]

[0076]

[0077] Formula 4-2

[0078]

[0079] In Formula 4-2, R 32 and R 36 may be a hydrogen atom, and R 33 and R 37 may each independently be a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted benzofurocarbazolyl group, a substituted or unsubstituted thiophenocarbazolyl group, a substituted or unsubstituted indolocarbazolyl group, a substituted or unsubstituted bi-carbazolyl group, a substituted or unsubstituted monoamino group, a substituted or unsubstituted diamino group, a substituted or unsubstituted acridane group, a substituted or unsubstituted phenoxazinyl group, or a substituted or unsubstituted phenothiazinyl group.

[0080] In certain embodiments, R 33 and R 37 may be a hydrogen atom, and R 32 and R 36Each may independently be a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted benzofurocarbazolyl group, a substituted or unsubstituted thiophenocarbazolyl group, a substituted or unsubstituted indolocarbazolyl group, a substituted or unsubstituted bi-carbazolyl group, a substituted or unsubstituted monoamino group, a substituted or unsubstituted diamino group, a substituted or unsubstituted acridanyl group, a substituted or unsubstituted phenoxazinyl group, or a substituted or unsubstituted phenothiazinyl group.

[0081] In an embodiment of the present disclosure, an organic electroluminescent device may include a first electrode, a second electrode on the first electrode, and a light-emitting layer between the first electrode and the second electrode. The light-emitting layer may include a first compound represented by Formula 1, a second compound represented by Formula 2, a third compound represented by Formula 3, and a fourth compound represented by Formula 4. Based on the total weight of the first compound to the fourth compound, the amount of the third compound may be about 10 wt% to about 15 wt%, and the amount of the fourth compound may be about 1 wt% to about 5 wt%. Formulas 1 to 4 may have the same structures as Formulas 1 to 4 described above.

[0082] In an embodiment, the weight ratio of the first compound to the second compound may be about 3:7 to about 7:3.

[0083] In an embodiment, the second compound may be represented by Formula 2-1, and the third compound may be represented by Formula 3-1. Formulas 2-1 and 3-1 may have the same structures as Formulas 2-1 and 3-1 described above.

[0084] In an embodiment, the second compound may be represented by Formula 2-1, and the third compound may be represented by Formula 3-2. Formulas 2-1 and 3-2 may have the same structures as Formulas 2-1 and 3-2 described above.

[0085] In an embodiment, the second compound may be represented by Formula 2-2, and the third compound may be represented by Formula 3-1. Formulas 2-2 and 3-1 may have the same structures as Formulas 2-2 and 3-1 described above.

[0086] In an embodiment of the present disclosure, an organic electroluminescent device may include a first electrode, a second electrode on the first electrode, and a light-emitting layer between the first electrode and the second electrode. The light-emitting layer may contain the compounds represented by Formulas 1 to 4 described above and emit delayed fluorescence. Description of the Drawings

[0087] The drawings are included to provide a further understanding of the present disclosure and are incorporated into and constitute a part of this specification. The drawings illustrate exemplary embodiments of the present disclosure and, together with the description, are used to explain the principles of the present disclosure. In the drawings:

[0088] Figure 1To schematically show a cross-sectional view of an organic electroluminescent device according to an embodiment of the present disclosure;

[0089] Figure 2 To schematically show a cross-sectional view of an organic electroluminescent device according to an embodiment of the present disclosure;

[0090] Figure 3 To schematically show a cross-sectional view of an organic electroluminescent device according to an embodiment of the present disclosure; and

[0091] Figure 4 To schematically show a cross-sectional view of an organic electroluminescent device according to an embodiment of the present disclosure. Detailed Embodiments

[0092] The present disclosure can have various modifications and can be implemented in different forms, and exemplary embodiments will be explained in detail with reference to the accompanying drawings. However, the present disclosure can be implemented in different forms and should not be construed as limited to the embodiments set forth herein. On the contrary, all modifications, equivalents, and alternatives falling within the spirit and technical scope of the present disclosure should be included in the present disclosure.

[0093] Throughout the specification, like reference numerals refer to like elements. In the drawings, the dimensions of the structures are enlarged for clarity of illustration. It should be understood that although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. Thus, without departing from the teachings of the present disclosure, a first element may be referred to as a second element. Similarly, a second element may be referred to as a first element. As used herein, the singular forms are also intended to include the plural forms unless the context clearly indicates otherwise.

[0094] The term "and / or" includes one or more combinations that can be defined by the relevant elements. Expressions such as "at least one", "one of which", and "selected from", when preceding a list of elements, modify the entire list of elements without modifying the individual elements of the list. In addition, when describing embodiments of the present disclosure, the use of "may" means "one or more embodiments of the present disclosure".

[0095] It will be further understood that when used in this specification, the terms "comprises", "comprising", "includes", "including", "has", "having" specify the presence of the stated features, numbers, steps, operations, elements, components, or combinations thereof, but do not preclude the presence or addition of one or more other features, numbers, steps, operations, elements, components, or combinations thereof.

[0096] It should also be understood that when a layer, film, region, plate, etc. is referred to as being "on" or "above" another part, it can be directly on top of the other part (with no intermediate layer therebetween), or there can also be an intermediate layer. Similarly, it should also be understood that when a layer, film, region, plate, etc. is referred to as being "under" or "below" another part, it can be directly under the other part (with no intermediate layer therebetween), or there can also be an intermediate layer. In addition, when one element is referred to as being on top of another element, it can be under the other element.

[0097] In the specification, the term "substituted or unsubstituted" corresponds to an unsubstituted group or a group substituted with at least one substituent selected from a deuterium atom, a halogen atom, a cyano group, a nitro group, an amino group, a silyl group, an oxy group, a thio group, a sulfinyl group, a sulfonyl group, a carbonyl group, a boron group, a phosphinyl oxide group, a phosphinyl sulfide group, an alkyl group, an alkenyl group, an alkoxy group, a hydrocarbon ring group, an aryl group, and a heterocyclic group (such as a heterocycle). Additionally, each substituent itself can be substituted or unsubstituted. For example, a biphenyl group can be interpreted as an aryl group substituted with a phenyl group or a phenyl group.

[0098] In the specification, the term "forming a ring by bonding to an adjacent group" can refer to forming a substituted or unsubstituted hydrocarbon ring or a substituted or unsubstituted heterocyclic ring by the bonding of one group to an adjacent group. The hydrocarbon ring includes an aliphatic hydrocarbon ring and an aromatic hydrocarbon ring. The heterocyclic ring includes an aliphatic heterocyclic ring and an aromatic heterocyclic ring. The ring formed by bonding to an adjacent group can be a monocyclic ring or a polycyclic ring. In addition, the ring formed by bonding to an adjacent group can combine with another ring to form a spiro ring structure.

[0099] In the specification, the term "adjacent group" can refer to a pair of substituents where the atom to which the first substituent is attached is directly connected to another atom substituted with the second substituent; a pair of substituents connected to the same atom; or a pair of substituents where the first substituent is spatially located closest to the second substituent. For example, in 1,2 - xylene, the two methyl groups can be interpreted as "adjacent groups" to each other, and in 1,1 - diethylcyclopentane, the two ethyl groups can be interpreted as "adjacent groups" to each other.

[0100] In the specification, the halogen atom can be a fluorine atom, a chlorine atom, a bromine atom, and / or an iodine atom.

[0101] In the specification, the alkyl group may be a straight-chain, branched-chain or cyclic alkyl group. The number of carbon atoms in the alkyl group may be 1 to 50, 1 to 30, 1 to 20, 1 to 10 or 1 to 6. Examples of the alkyl group may include methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, isobutyl, 2-ethylbutyl, 3,3-dimethylbutyl, n-pentyl, isopentyl, neopentyl, tert-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, n-heptyl, 1-methylheptyl, 2,2-dimethylheptyl, 2-ethylheptyl, 2-butylheptyl, n-octyl, tert-octyl, 2-ethyloctyl, 2-butyl octyl, 2-hexyloctyl, 3,7-dimethyloctyl, cyclooctyl, n-nonyl, n-decyl, adamantyl, 2-octyl decyl, 2-butyl decyl, 2-hexyldecyl, 2-octyl decyl, n-undecyl, n-dodecyl, 2-ethyldodecyl, 2-butyl dodecyl, 2-hexyldodecyl, 2-octyldodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, 2-ethylhexadecyl, 2-butyl hexadecyl, 2-hexylhexadecyl, 2-octylhexadecyl, n-heptadecyl, n-octadecyl, n-nonadecyl, n-eicosyl, 2-ethyleicosyl, 2-butyl eicosyl, 2-hexyleicosyl, 2-octyleicosyl, n-heneicosyl, n-docosyl, n-tricosyl, n-tetracosyl, n-pentacosyl, n-hexacosyl, n-heptacosyl, n-octacosyl, n-nonacosyl, n-triacontyl, etc., without limitation.

[0102] In the specification, the hydrocarbon ring group may refer to a functional group or substituent derived from an aliphatic hydrocarbon ring. The hydrocarbon ring group may be a saturated hydrocarbon ring group having 5 to 20 ring-forming carbon atoms.

[0103] In the specification, the aryl group may refer to a functional group or substituent derived from an aromatic hydrocarbon ring. The aryl group may be a monocyclic aryl group or a polycyclic aryl group. The number of carbon atoms used to form the ring in the aryl group may be 6 to 30, 6 to 20 or 6 to 15. Examples of the aryl group may include phenyl, naphthyl, fluorenyl, anthracenyl, phenanthryl, biphenyl, terphenyl, quaterphenyl, quinquephenyl, sexiphenyl, benzophenanthryl, pyrenyl, benzo[a]pyrenyl, groups, etc., without limitation.

[0104] In the specification, the fluorenyl group may be substituted, and two substituents may be combined with each other to form a spiro ring structure. Examples of the substituted fluorenyl group are as follows. However, the embodiments of the present disclosure are not limited thereto:

[0105]

[0106] In the specification, the heterocyclic group may contain one or more selected from B, O, N, P, Si, and S as heteroatoms. If the heterocyclic group contains two or more heteroatoms, the two or more heteroatoms may be the same or different. The heterocyclic group may be a monocyclic heterocyclic group or a polycyclic heterocyclic group, and includes a heteroaryl group. The number of carbon atoms for forming the ring of the heterocyclic group (e.g., heteroaryl group) may be 2 to 30, 2 to 20, or 2 to 10.

[0107] In the specification, the aliphatic heterocyclic group may contain one or more selected from B, O, N, P, Si, and S as heteroatoms. The number of carbon atoms for forming the ring of the aliphatic heterocyclic group may be 2 to 30, 2 to 20, or 2 to 10. Examples of the aliphatic heterocyclic group may include, without limitation, oxiranyl, thioethylenyl, pyrrolidinyl, piperidinyl, tetrahydrofuryl, tetrahydrothienyl, thiacyclopentyl, tetrahydropyranyl, 1,4-dioxanyl, etc.

[0108] In the specification, the number of carbon atoms for forming the ring of the heteroaryl group may be 2 to 30, 2 to 20, or 2 to 10. Examples of the heteroaryl group may include, without limitation, thienyl, furyl, pyrrolyl, imidazolyl, thiazolyl, oxazolyl, oxadiazolyl, triazolyl, pyridyl, bipyridyl, pyrimidinyl, triazinyl, acridinyl, pyridazinyl, pyrazinyl, 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, isoxazolyl, thiadiazolyl, phenothiazinyl, acridanyl, dibenzosilole group, dibenzofuryl, etc.

[0109] For example, the carbazolyl group may be a bi-carbazolyl group, a benzofurocarbazolyl group, a thienocarbazolyl group, and / or an indolocarbazolyl group, without limitation.

[0110] In the specification, the explanation of the aryl group can be applied to the arylene group except that the arylene group is a divalent group. The explanation of the heteroaryl group can be applied to the heteroarylene group except that the heteroarylene group is a divalent group. The explanation of the alkyl group can be applied to the divalent alkyl group except that the divalent alkyl group is a divalent group.

[0111] In the specification, silyl includes alkylsilyl, arylsilyl, and heteroarylsilyl. The explanations of the above alkyl, aryl, and heteroaryl can be applied to the alkyl, aryl, and heteroaryl in arylsilyl and heteroarylsilyl. Examples of silyl can include trimethylsilyl, triethylsilyl, tert-butyldimethylsilyl, vinyldimethylsilyl, propyldimethylsilyl, triphenylsilyl, diphenylsilyl, phenylsilyl, etc., without limitation.

[0112] In the specification, the number of carbon atoms of the amino group is not particularly limited, but can be 1 to 30. The amino group can include alkylamino, arylamino, and / or heteroarylamino. The explanations of the above alkyl, aryl, and heteroaryl can be applied to the alkyl, aryl, and heteroaryl in alkylamino, arylamino, and heteroarylamino. Examples of the amino group include methylamino, dimethylamino, phenylamino, diphenylamino, naphthylamino, 9-methyl-anthrylamino, triphenylamino, etc., without limitation.

[0113] In the specification, the number of carbon atoms of the carbonyl group is not particularly limited, but can be 1 to 40, 1 to 30, or 1 to 20. For example, the carbonyl group can have the following structures, but the embodiments of the present disclosure are not limited thereto:

[0114]

[0115] In the specification, alkenyl can be a straight-chain or branched-chain hydrocarbon group having one or more carbon-carbon double bonds at one or more positions along the hydrocarbon chain. The number of carbon atoms of alkenyl is not particularly limited, but can be 2 to 30, 2 to 20, or 2 to 10. Examples of alkenyl can include vinyl, 1-butenyl, 1-pentenyl, 1,3-butadienyl aryl, styryl, styrylviny, etc., without limitation.

[0116] In the specification, alkynyl can be a straight-chain or branched-chain hydrocarbon group having one or more carbon-carbon triple bonds at one or more positions along the hydrocarbon chain. The number of carbon atoms of alkynyl is not particularly limited, but can be 2 to 30, 2 to 20, or 2 to 10. Examples of alkynyl can include ethynyl, 1-butynyl, 1-pentynyl, 1,3-butadiynyl aryl, etc., without limitation.

[0117] In the specification, "ring-forming atom" can refer to an atom that forms a ring.

[0118] In the specification, direct connection can refer to a single bond.

[0119] Figure 1To schematically show a cross-sectional view of an organic electroluminescent device according to an embodiment of the present disclosure. The organic electroluminescent device 10 according to an embodiment may include a first electrode EL1, a hole transport region HTR, a light-emitting layer EML, an electron transport region ETR, and a second electrode EL2, which are stacked in sequence.

[0120] Figures 1 to 4 To schematically show a cross-sectional view of an organic electroluminescent device according to an embodiment of the present disclosure. Referring to Figures 1 to 4 , in the organic electroluminescent device 10 according to one or more embodiments, the first electrode EL1 and the second electrode EL2 are disposed opposite to each other, and a light-emitting layer EML may be disposed between the first electrode EL1 and the second electrode EL2.

[0121] In addition, in addition to the light-emitting layer EML, the organic electroluminescent device 10 further includes a plurality of functional groups (functional layers) between the first electrode EL1 and the second electrode EL2. The plurality of functional groups (functional layers) may include a hole transport region HTR and an electron transport region ETR. For example, the organic electroluminescent device 10 according to an embodiment may include a first electrode EL1, a hole transport region HTR, a light-emitting layer EML, an electron transport region ETR, and a second electrode EL2, which are stacked in sequence. In some embodiments, the organic electroluminescent device 10 may include a cover layer CPL on the second electrode EL2.

[0122] The organic electroluminescent device 10 according to an embodiment may include one or more compounds according to the embodiment disposed in the light-emitting layer EML between the first electrode EL1 and the second electrode EL2, which will be explained in more detail later. However, the embodiments of the present disclosure are not limited thereto, and in addition to in the light-emitting layer EML, the organic electroluminescent device 10 may further include one or more compounds according to the embodiment in the hole transport region HTR and / or the electron transport region ETR, which are functional groups (functional layers) between the first electrode EL1 and the second electrode EL2, or in the cover layer CPL on the second electrode EL2.

[0123] Compared with Figure 1 Figure 2 shows a cross-sectional view of the organic electroluminescent device 10 according to an embodiment, wherein the hole transport region HTR includes a hole injection layer HIL and a hole transport layer HTL, and the electron transport region ETR includes an electron injection layer EIL and an electron transport layer ETL. Additionally, when compared with Figure 1 Figure 3A cross-sectional view of an organic electroluminescent device 10 according to an embodiment is shown, wherein the hole transport region HTR includes a hole injection layer HIL, a hole transport layer HTL, and an electron blocking layer EBL, and the electron transport region ETR includes an electron injection layer EIL, an electron transport layer ETL, and a hole blocking layer HBL. When compared with Figure 2 when compared Figure 4 A cross-sectional view of an organic electroluminescent device 10 according to an embodiment is shown, including a cover layer CPL on the second electrode EL2.

[0124] The first electrode EL1 has conductivity. The first electrode EL1 can be formed using a metal alloy or any suitable conductive compound. The first electrode EL1 can be an anode. In some embodiments, the first electrode EL1 can be a pixel electrode. The first electrode EL1 can be a transmissive electrode, a semi-transmissive semi-reflective electrode, or a reflective electrode. If the first electrode EL1 is a transmissive electrode, the first electrode EL1 can include a transparent metal oxide, such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), and / or indium tin zinc oxide (ITZO). If the first electrode EL1 is a semi-transmissive semi-reflective electrode or a reflective electrode, the first electrode EL1 can contain Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF / Ca, LiF / Al, Mo, Ti, their compounds, or their mixtures (e.g., a mixture of Ag and Mg). In some embodiments, the first electrode EL1 can have a structure including multiple layers, the multiple layers including a reflective layer and / or a semi-transmissive semi-reflective layer formed using any of the above materials, and a transmissive conductive layer formed using ITO, IZO, ZnO, ITZO, etc. For example, the first electrode EL1 can include a three-layer structure of ITO / Ag / ITO. However, the embodiments of the present disclosure are not limited thereto. The thickness of the first electrode EL1 can be approximately to approximately For example, approximately to approximately

[0125] The hole transport region HTR can be disposed on the first electrode EL1. The hole transport region HTR can include at least one of a hole injection layer HIL, a hole transport layer HTL, a hole buffer layer, or an electron blocking layer EBL.

[0126] The hole transport region HTR can have a single-layer structure formed using a single material, a single-layer structure formed using multiple different materials, or a multilayer structure including multiple layers formed using multiple different materials.

[0127] For example, the hole transport region HTR may have a single-layer structure of a hole injection layer HIL or a hole transport layer HTL, or a single-layer structure formed using a hole injection material and a hole transport material. In certain embodiments, the hole transport region HTR may have a single-layer structure formed using a plurality of different materials, or a structure stacked by a first electrode EL1 of a hole injection layer HIL / hole transport layer HTL, a hole injection layer HIL / hole transport layer HTL / hole buffer layer, a hole injection layer HIL / hole buffer layer, a hole transport layer HTL / hole buffer layer, or a hole injection layer HIL / hole transport layer HTL / electron blocking layer EBL, without limitation.

[0128] The hole transport region HTR can be formed using one or more suitable methods, such as vacuum deposition, spin coating, casting, Langmuir-Blodgett (LB) method, inkjet printing, laser printing, and / or laser-induced thermal imaging (LITI) method.

[0129] The hole injection layer HIL may include, for example, 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-styrenesulfonate) (PEDOT / PSS), polyaniline / dodecylbenzenesulfonic acid (PANI / DBSA), polyaniline / camphorsulfonic acid (PANI / CSA), polyaniline / poly(4-styrenesulfonate) (PANI / PSS), N,N'-bis(1-naphthalen-1-yl)-N,N'-diphenyl-benzidine (NPB), triphenylamine containing polyether ketone (TPAPEK), 4-isopropyl-4'-methyldiphenyliodonium tetrakis(pentafluorophenyl)borate, and / or dipyrazino[2,3-f:2',3'-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile (HAT-CN).

[0130] The hole transport layer (HTL) may include, for example, carbazole derivatives (e.g., N-phenylcarbazole and / or polyvinylcarbazole), fluorene-based derivatives, N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (TPD), triphenylamine-based derivatives (e.g., 4,4',4''-tris(carbazol-9-yl)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), etc.

[0131] The thickness of the hole transport region (HTR) may be about to about For example, about to about The thickness of the hole injection layer (HIL) may be, for example, about to about And the thickness of the hole transport layer (HTL) may be about to about For example, the thickness of the electron blocking layer (EBL) may be about to about If the thicknesses of the hole transport region (HTR), the hole injection layer (HIL), the hole transport layer (HTL), and the electron blocking layer (EBL) satisfy the above ranges, satisfactory (or appropriate) hole transport performance can be achieved without significantly increasing the driving voltage.

[0132] In addition to the above materials, the hole transport region (HTR) may further include a charge generation material to increase conductivity. The charge generation material may be uniformly or non-uniformly dispersed in the hole transport region (HTR). For example, the charge generation material may be a p-type dopant. The p-type dopant may be one selected from quinone derivatives, metal oxides, and cyanide-containing compounds, without limitation. Non-limiting examples of the p-type dopant may include quinone derivatives (e.g., tetracyanoquinodimethane (TCNQ) and / or 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ)) and metal oxides (e.g., tungsten oxide and / or molybdenum oxide), etc., without limitation.

[0133] As described above, in addition to the hole injection layer HIL and the hole transport layer HTL, the hole transport region HTR may further include at least one of a hole buffer layer or an electron blocking layer EBL. The hole buffer layer may compensate for the optical resonance distance according to the wavelength of the light emitted from the light emitting layer EML to improve the light emitting efficiency. The material that may be included in the hole transport region HTR may be used as the material included in the hole buffer layer. The electron blocking layer EBL may prevent or reduce the electron injection from the electron transport region ETR to the hole transport region HTR.

[0134] The light emitting layer EML may be disposed on the hole transport region HTR. For example, the light emitting layer EML may have a thickness of about to about or about to about The light emitting layer EML may have a single layer formed of a single material, a single layer formed of a plurality of different materials, or a multi-layer structure having a plurality of layers formed of a plurality of different materials.

[0135] In an embodiment, the light emitting layer EML may include a first compound, a second compound, a third compound, and a fourth compound of the embodiment, which will be explained in more detail later. The first to fourth compounds may be different compounds.

[0136] In an embodiment, the first compound may be represented by the following formula 1:

[0137] Formula 1

[0138]

[0139] In formula 1, R1 and R2 may each independently be an aryl or a heteroaryl. The aryl may be an aryl having 6 to 30 ring-forming carbon atoms, which may be substituted or unsubstituted. The heteroaryl may be a heteroaryl having 3 to 30 ring-forming carbon atoms, which may be substituted or unsubstituted. "a" and "b" may each independently be an integer from 0 to 4. For example, "a" and "b" may be 0. That is, the benzene ring of the carbazolyl group in formula 1 may be unsubstituted.

[0140] L1 may be a direct bond, an arylene or a heteroarylene. The arylene may be an arylene having 6 to 30 ring-forming carbon atoms, which may be substituted or unsubstituted. The heteroarylene may be a heteroarylene having 3 to 30 ring-forming carbon atoms, which may be substituted or unsubstituted. L1 may be a substituted or unsubstituted phenylene group, a substituted or unsubstituted divalent biphenyl group, or a substituted or unsubstituted carbazolylene group. If L1 is substituted, the substituent of L1 may be an aryl and / or a heteroaryl. For example, L1 may be a divalent group substituted with a phenyl group and / or a carbazolyl group.

[0141] Ar1 can be an aryl or a heteroaryl. The aryl can be an aryl having 6 to 30 ring-forming carbon atoms which is substituted or unsubstituted. The heteroaryl can be a heteroaryl having 3 to 30 ring-forming carbon atoms which is substituted or unsubstituted. For example, Ar1 can be a dibenzoheterocyclic group represented by Formula A:

[0142] Formula A

[0143]

[0144] In Formula A, X can be a heteroatom. For example, X can be B, O, N, P, Si or S. The benzene rings in Formula A can each independently be substituted with a substituent. For example, Formula A can be a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted dibenzofuranyl group, or a substituted or unsubstituted dibenzothiophenyl group. Formula A can be an unsubstituted carbazolyl group, an unsubstituted dibenzofuranyl group or an unsubstituted dibenzothiophenyl group.

[0145] In an embodiment, the second compound can be represented by Formula 2:

[0146] Formula 2

[0147]

[0148] In Formula 2, Z1 to Z3 can each independently be CR 11 , or N. For example, all of Z1 to Z3 can be CR 11 , or all can be N.

[0149] Multiple Rs 11 and multiple Rs 12 can each independently be a hydrogen atom, a deuterium atom, a cyano group, a silyl group, an aryl or a heteroaryl. The silyl group can be a substituted silyl group. Multiple Rs 11 can be the same or different. Multiple Rs 12 can be the same or different. The aryl can be an aryl having 6 to 30 ring-forming carbon atoms which is substituted or unsubstituted. The heteroaryl can be a heteroaryl having 3 to 30 ring-forming carbon atoms which is substituted or unsubstituted.

[0150] The substituted silyl group can be an arylsilyl group and / or a heteroarylsilyl group. For example, the aryl in the arylsilyl group can be an aryl substituted with a heteroaryl.

[0151] The aryl can be a substituted or unsubstituted phenyl group. The heteroaryl can be a substituted or unsubstituted pyridyl group and / or the dibenzoheterocyclic group represented by Formula A as described above. For example, the heteroaryl can be a substituted or unsubstituted carbazolyl group and / or a substituted or unsubstituted dibenzofuranyl group.

[0152] Formula 2 can be represented by Formula 2-1:

[0153] Formula 2-1

[0154]

[0155] In Formula 2-1, multiple Rs 12 can each independently be an aryl group having 6 to 30 ring carbon atoms which is substituted or unsubstituted, or a heteroaryl group having 3 to 30 ring carbon atoms which is substituted or unsubstituted. For example, Rs 12 can each independently be a phenyl group substituted with triphenylmethyl, a phenyl group substituted with triphenylsilyl, a phenyl group substituted with methyl, or a carbazolyl group substituted with phenyl.

[0156] Formula 2 can be represented by Formula 2-2:

[0157] Formula 2-2

[0158]

[0159] In Formula 2-2, multiple Rs 11 and multiple Rs 12 can each independently be a hydrogen atom, a deuterium atom, a cyano group, a substituted silyl group, an aryl group having 6 to 30 ring carbon atoms which is substituted or unsubstituted, or a heteroaryl group having 3 to 30 ring carbon atoms which is substituted or unsubstituted. At least one selected from multiple Rs 11 and multiple Rs 12 can be a cyano group, or an aromatic ring group containing at least one cyano group as a substituent. The aromatic ring group containing at least one cyano group as a substituent can be: an aryl group having 6 to 30 ring carbon atoms containing at least one cyano group as a substituent and / or a heteroaryl group having 3 to 20 ring carbon atoms containing at least one cyano group as a substituent. The aromatic ring group containing at least one cyano group as a substituent can be a carbazolyl group substituted with a cyano group, and / or a dibenzofuranyl group substituted with a cyano group.

[0160] In an embodiment, the third compound can be represented by Formula 3:

[0161] Formula 3

[0162]

[0163] In Formula 3, A1 and A4 can each independently be an aryl group or a heteroaryl group. The aryl group can be an aryl group having 6 to 30 ring carbon atoms which is substituted or unsubstituted. The heteroaryl group can be a heteroaryl group having 1 to 30 ring carbon atoms which is substituted or unsubstituted.

[0164] X1 to X4 can each independently be C or N.

[0165] R 21 to R 24 can each independently be a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, an amino group, an alkyl group, an aryl group or a heteroaryl group, and R21 to R 24 Any one of them can combine with an adjacent group to form a ring. The amino group can be a substituted or unsubstituted amino group. The alkyl group can be a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms. The aryl group can be a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms. The heteroaryl group can be a substituted or unsubstituted heteroaryl group having 1 to 30 ring-forming carbon atoms. d1 to d4 can each independently be an integer from 0 to 4. For example, in the case where R 21 to R 24 is an alkyl group, it can include methyl, isopropyl and / or tert-butyl. In the case where R 21 to R 24 is an amino group, it can include dimethylamino. In the case where R 21 to R 24 is a halogen atom, it can include fluorine atom (F).

[0166] L 21 to L 23 can each independently be a direct bond, *-O-*, *-S-*, a divalent alkyl group, an arylene group or a heteroarylene group. The divalent alkyl group can be a substituted or unsubstituted divalent alkyl group having 1 to 20 carbon atoms. The arylene group can be a substituted or unsubstituted arylene group having 6 to 30 ring-forming carbon atoms. The heteroarylene group can be a substituted or unsubstituted heteroarylene group having 2 to 30 ring-forming carbon atoms.

[0167] In L 21 to L 23 , the -* refers to the part connected to A1 to A4.

[0168] R 25 to R 27 can each independently be an alkyl group, an aryl group or a heteroaryl group, and any one of R 25 to R 27 can combine with an adjacent group to form a ring. The alkyl group can be a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms. The aryl group can be a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms. The heteroaryl group can be a substituted or unsubstituted heteroaryl group having 3 to 30 ring-forming carbon atoms. d5 can be an integer from 0 to 8. For example, d5 can be 0.

[0169] M can be a metal atom. For example, M can be platinum, palladium, copper, osmium, iridium, rubidium or rhodium. e1 to e3 can each independently be 0 or 1. m can be 1 or 2. When M is platinum, palladium, copper or osmium, "m" can be 1. When M is iridium, rubidium or rhodium, "m" can be 2, and e2 can be 0.

[0170] A1 to A4 can each independently be represented by any one selected from Structures 1-1 to 1-3:

[0171]

[0172] In structures 1-1 to 1-3, Y1 can be C-* or CR 54 . Y2 can be N-* or NR 61 . Y3 can be N-* or NR 62 . In structures 1-1 to 1-3, refers to the part connected to the metal atom. -* refers to the part connected to the adjacent ligand (i.e., A1 to A4) or linker (i.e., L 21 to L 23 ).

[0173] R 51 to R 64 can each independently be alkyl, aryl or heteroaryl, and any one of R 51 to R 64 can combine with an adjacent group to form a ring. The alkyl can be a substituted or unsubstituted alkyl of 1 to 20 carbon atoms. The aryl can be a substituted or unsubstituted aryl of 6 to 30 ring-forming carbon atoms. The heteroaryl can be a substituted or unsubstituted heteroaryl of 6 to 30 ring-forming carbon atoms.

[0174] For example, R 63 and R 64 can combine with each other to form a ring. For example, structure 1-3 can be represented by any one of the following structures 1-3-1 to 1-3-3:

[0175]

[0176] In structures 1-3-1 to 1-3-3, Y3 can be the same as defined in structure 1-3.

[0177] A1 to A4 can each independently be represented by structure 2-1 or structure 2-2:

[0178]

[0179] In structure 2-1, Y 11 and Y 12 can each independently be C or N, and Y 13 to Y 16 can each independently be N or CR 71 . For example, structure 2-1 can include phenyl derivatives, pyridine derivatives and / or 1,3,5-triazine derivatives.

[0180] R 71may each independently be a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, an amino group, an alkyl group, an aryl group or a heteroaryl group, and any one of R 71 may combine with an adjacent group to form a ring. The amino group may be a substituted or unsubstituted amino group. The alkyl group may be a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms. The aryl group may be a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms. The heteroaryl group may be a substituted or unsubstituted heteroaryl group having 1 to 30 ring-forming carbon atoms.

[0181] In Structure 2-2, Y 17 and Y 18 may each independently be N or CR 72 . R 72 and R 73 may each independently be a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, an amino group, an alkyl group, an aryl group or a heteroaryl group, and any one of R 72 and R 73 may combine with an adjacent group to form a ring. The amino group may be a substituted or unsubstituted amino group. The alkyl group may be a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms. The aryl group may be a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms. The heteroaryl group may be a substituted or unsubstituted heteroaryl group having 1 to 30 ring-forming carbon atoms. For example, R 72 may be a hydrogen atom. For example, R 73 may be a methyl group.

[0182] In Formula 3, A1 to A4 may each independently be represented by any one selected from Structures 1-1 to 1-3, 2-1 and 2-2:

[0183] Formula 3 may be represented by Formula 3-1:

[0184] Formula 3-1

[0185]

[0186] In Formula 3-1, A1 to A4, X1 to X4, R 21 to R 24 , d1 to d4 and L 22 may be the same as those defined in Formula 3. For example, A1 to A4 may each independently be represented by any one selected from the above Structures 1-1 to 1-3:

[0187] Formula 3 may be represented by Formula 3-2:

[0188] Formula 3-2

[0189]

[0190] In Formula 3-2, A1 to A4, X1 to X4, R 21To R 24 , and d1 to d4 can be the same as those defined in Formula 3. For example, A1 to A4 can each independently be represented by Structure 2-1 or Structure 2-2 described above:

[0191] For example, Formula 3-2 can be represented by Formula 3-2-1:

[0192] Formula 3-2-1

[0193]

[0194] Y 13 and Y 15 can be the same as those defined in Structure 2-1. In Formula 3-2-1, R 72 and R 73 can be the same as those defined in Structure 2-2.

[0195] R 71-1 , R 71-2 and R 71-3 can be the same as the definition of R 71 . f1 can be an integer from 0 to 4. If f1 is greater than 2, multiple R 71-1 can be the same or different. f2 can be 1 or 2. If f2 is 2, the two R 71-2 groups can be the same or different. f3 can be an integer from 0 to 3. If f3 is greater than 2, multiple R 71-3 can be the same or different.

[0196] In an embodiment, the fourth compound can be represented by Formula 4:

[0197] Formula 4

[0198]

[0199] In Formula 4, R 31 to R 41 can each independently be a hydrogen atom, a deuterium atom, a halogen atom, a silyl group, an amino group, a carbonyl group, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, or a heteroaryl group. The silyl group can be a substituted or unsubstituted silyl group. The amino group can be a substituted or unsubstituted amino group. The carbonyl group can be a substituted or unsubstituted carbonyl group. The alkyl group can be a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms. The alkenyl group can be a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms. The alkynyl group can be a substituted or unsubstituted alkynyl group having 2 to 20 carbon atoms. The aryl group can be a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms. The heteroaryl group can be a substituted or unsubstituted heteroaryl group having 3 to 30 ring-forming carbon atoms. At least one of R 31 to R 41 can be not a hydrogen atom.

[0200] For example, R 31 to R 41 may each independently be trideuteriomethyl (CD3), isopropyl, tert-butyl, trimethylsilyl, triphenylsilyl, substituted or unsubstituted acetyl, substituted or unsubstituted fluorenyl, substituted or unsubstituted imidazolyl, substituted or unsubstituted triazinyl, substituted or unsubstituted pyridyl, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted carbazolyl, substituted or unsubstituted benzofurocarbazolyl, substituted or unsubstituted thiophenocarbazolyl, substituted or unsubstituted indolocarbazolyl, substituted or unsubstituted bi-carbazolyl, substituted or unsubstituted monoamino, substituted or unsubstituted diamino, substituted or unsubstituted acridinyl, substituted or unsubstituted phenoxazinyl or substituted or unsubstituted phenothiazinyl. The substituted monoamino and substituted diamino may not contain nitrogen as a substituent. For example, the substituted monoamino may be dimethylamino and / or diarylamino.

[0201] Formula 4 may be represented by Formula 4-1:

[0202] Formula 4-1

[0203]

[0204] R 32 、R 33 、R 36 、R 37 and R 40 may have the same definitions as in Formula 4. At least one selected from R 32 、R 33 、R 36 、R 37 and R 40 may not be a hydrogen atom.

[0205] Formula 4-1 may be represented by the following Formula 4-2:

[0206] Formula 4-2

[0207]

[0208] In Formula 4-2, R 32 、R 33 、R 36 and R 37 may have the same definitions as in Formula 4. For example, in Formula 4-2, R 32 and R 36 may be hydrogen atoms, and R 33 and R 37 may not be hydrogen atoms. In some embodiments, R 32 and R 36 may not be hydrogen atoms, and R 33 and R 37It may be a hydrogen atom.

[0209] The first compound of the embodiment may include at least one selected from the compounds represented in the following Compound Group 1:

[0210] Compound Group 1

[0211]

[0212]

[0213] The second compound of the embodiment may include at least one selected from the compounds represented in the following Compound Group 2-1:

[0214] Compound Group 2-1

[0215]

[0216]

[0217] The second compound of the embodiment may include at least one selected from the compounds represented in the following Compound Group 2-2:

[0218] Compound Group 2-2

[0219]

[0220]

[0221] The third compound of the embodiment may include at least one selected from the compounds represented in the following Compound Group 3-1:

[0222] Compound Group 3-1

[0223]

[0224]

[0225] The third compound of the embodiment may include at least one selected from the compounds represented in the following Compound Group 3-2:

[0226] Compound Group 3-2

[0227]

[0228]

[0229] The fourth compound of the embodiment may include at least one selected from the compounds represented in the following Compound Group 4 and Formula 4-2:

[0230] Compound Group 4

[0231]

[0232]

[0233]

[0234]

[0235]

[0236]

[0237] Formula 4-2

[0238]

[0239] In Formula 4-2, wherein R 32 and R 36 are hydrogen atoms, R 33 and R 37 can each independently be a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted benzofurocarbazolyl group, a substituted or unsubstituted thiophenocarbazolyl group, a substituted or unsubstituted indolocarbazolyl group, a substituted or unsubstituted bi-carbazolyl group, a substituted or unsubstituted monoamino group, a substituted or unsubstituted diamino group, a substituted or unsubstituted acridanyl group, a substituted or unsubstituted phenoxazinyl group, or a substituted or unsubstituted phenothiazinyl group.

[0240] In Formula 4-2, wherein R 33 and R 37 are hydrogen atoms, R 32 and R 36 can each independently be a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted benzofurocarbazolyl group, a substituted or unsubstituted thiophenocarbazolyl group, a substituted or unsubstituted indolocarbazolyl group, a substituted or unsubstituted bi-carbazolyl group, a substituted or unsubstituted monoamino group, a substituted or unsubstituted diamino group, a substituted or unsubstituted acridanyl group, a substituted or unsubstituted phenoxazinyl group, or a substituted or unsubstituted phenothiazinyl group.

[0241] For example, in Formula 4-2, R 32 、R 33 、R 36 and R 37 can be defined as described in Table 1 below.

[0242] Table 1

[0243]

[0244]

[0245]

[0246]

[0247]

[0248]

[0249]

[0250]

[0251]

[0252]

[0253] In Table 1, the carbazolyl group, benzofurocarbazolyl group, thiophenocarbazolyl group, indolocarbazolyl group, bi-carbazolyl group, monoamino group, diamino group, acridanyl group, phenoxazinyl group, and phenothiazinyl group may each independently be substituted or unsubstituted.

[0254] In Figures 1 to 4 In the organic electroluminescent device 10 of the illustrated embodiment, the light-emitting layer EML may include a host compound and a dopant compound. The light-emitting layer EML may contain two or more host compounds and dopant compounds, respectively.

[0255] The first compound of the embodiment may be used as a host material in the light-emitting layer EML. Since the first compound of the embodiment contains a dibenzoheterocycle, such as a carbazolyl group and / or a dibenzofuranyl group, the first compound may be a host compound having excellent (or suitable) hole-transporting properties.

[0256] The second compound of the embodiment may be used as a host material in the light-emitting layer EML. Since the second compound of the embodiment contains a triazinyl group and / or a cyano group, the second compound may be a host compound having excellent (or suitable) electron-transporting properties.

[0257] The light-emitting layer of the embodiment includes a first compound having excellent (or suitable) hole-transporting properties as a first host, and a second compound having excellent (or suitable) electron-transporting properties as a second host. Therefore, effective energy transfer from the host to the dopant can be achieved.

[0258] The third compound of the embodiment can be a phosphorescent dopant compound. The third compound of the embodiment can have a higher lowest triplet energy level than the fourth compound of the embodiment. The third compound of the embodiment can transfer energy from the host to the fourth compound. For example, the third compound of the embodiment can be included in the emitting layer EML and used as an auxiliary dopant to assist the luminescence of the luminescent dopant.

[0259] The fourth compound of the embodiment can be a thermally activated delayed fluorescence (TADF) dopant. The fourth compound of the embodiment can be used as a luminescent dopant in the emitting layer EML. In the embodiment, the fourth compound can emit blue light. For example, the emitting layer EML can emit fluorescence, and more specifically, delayed fluorescence. The emitting layer EML can emit blue light as delayed fluorescence.

[0260] The emitting layer of the embodiment includes a third compound and a fourth compound. The third compound as an auxiliary dopant can accelerate the delayed fluorescence of the fourth compound. Therefore, the emitting layer of the embodiment can exhibit improved luminous efficiency. In some embodiments, in the case of accelerating the delayed fluorescence, the excitons formed in the emitting layer do not accumulate in the emitting layer but emit light quickly, thereby reducing the deterioration of the device. Therefore, the lifetime of the organic electroluminescent device of the embodiment can be increased.

[0261] Based on the total weight of the first compound, the second compound, the third compound, and the fourth compound, the amount of the third compound in the emitting layer EML can be about 10 wt% to about 15 wt%. Based on the total weight of the first compound, the second compound, the third compound, and the fourth compound, the amount of the fourth compound in the emitting layer EML can be about 1 wt% to about 5 wt%.

[0262] When the amounts of the third compound and the fourth compound satisfy the above ratios, energy can be effectively (or appropriately) transferred from the third compound to the fourth compound. Therefore, the luminous efficiency and the device lifetime can be increased.

[0263] In the emitting layer EML, the first compound and the second compound can be included in an amount that is the total weight (amount) minus the weights (amounts) of the third compound and the fourth compound. For example, based on the total weight of the first compound, the second compound, the third compound, and the fourth compound, the amounts of the first compound and the second compound in the emitting layer EML can be about 80 wt% to about 89 wt%. In the total weight of the first compound and the second compound, the weight ratio of the first compound to the second compound can be about 3:7 to about 7:3.

[0264] When the amounts of the first compound and the second compound satisfy the above ratio, the charge balance performance in the emission layer (EML) can be improved, and the luminous efficiency and device lifetime can be increased. When the amounts of the first compound and the second compound deviate from the above ratio range, the charge balance in the emission layer (EML) may be broken (or reduced), the luminous efficiency may be reduced, and the device may be prone to deterioration.

[0265] When the amounts of the first to fourth compounds in the emission layer (EML) satisfy the above range, excellent luminous efficiency and long lifetime can be achieved.

[0266] In the organic electroluminescent device 10 of the embodiment, the emission layer (EML) may further include any one of an anthracene derivative, a pyrene derivative, a fluoranthene derivative, a derivative, a dihydrobenzanthracene derivative, or a benzophenanthrene derivative. For example, the emission layer (EML) may include an anthracene derivative and / or a pyrene derivative.

[0267] The emission layer (EML) may include the compound represented by Formula 2-1 as the second compound and the compound represented by Formula 3-1 as the third compound. In some embodiments, the emission layer (EML) may include the compound represented by Formula 2-1 as the second compound and the compound represented by Formula 3-2 as the third compound. In some embodiments, the emission layer (EML) may include the compound represented by Formula 2-2 as the second compound and the compound represented by Formula 3-1 as the third compound. However, the embodiments of the present disclosure are not limited thereto. For example, the emission layer (EML) may include the compound represented by Formula 2-2 as the second compound and the compound represented by Formula 3-2 as the third compound.

[0268] The light-emitting layer EML may also include any suitable host material. For example, the light-emitting layer EML may include at least one of bis[2-(diphenylphosphino)phenyl]ether oxide (DPEPO), 4,4'-bis(carbazol-9-yl)biphenyl (CBP), 1,3-bis(carbazol-9-yl)benzene (mCP), 2,8-bis(diphenylphosphoryl)dibenzofuran (PPF), tris(4-carbazol-9-ylphenyl)amine (TCTA), or 1,3,5-tris(1-phenyl-1H-benzo[d]imidazol-2-yl)benzene (TPBi) as the host material. However, the embodiments of the present disclosure are not limited thereto. 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), tris(4-carbazol-9-ylphenyl)amine (TCTA), 1,3,5-tris(1-phenyl-1H-benzo[d]imidazol-2-yl)benzene (TPBi), 3-tert-butyl-9,10-bis(naphthalen-2-yl)anthracene (TBADN), stilbenes (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), hexaphenylphosphazene (CP1), 1,4-bis(triphenylsilyl)benzene (UGH2), hexaphenylcyclotrisiloxane (DPSiO3), octaphenylcyclotetrasiloxane (DPSiO4), 2,8-bis(diphenylphosphoryl)dibenzofuran (PPF), etc. may be used as the host material.

[0269] In an embodiment, the light-emitting layer EML 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]diphenylethylene (DPAVB), and / or N-(4-((E)-2-(6-((E)-4-(diphenylamino)styryl)naphthalen-2-yl)vinyl)phenyl)-N-phenylaniline (N-BDAVBi)), perylene and / or its derivatives (e.g., 2,5,8,11-tetra-tert-butylperylene (TBP)), pyrene and / or its derivatives (e.g., 1,1-dipyrene, 1,4-dipyrenylbenzene, 1,4-bis(N,N-diphenylamino)pyrene), etc. as the dopant material.

[0270] In Figures 1 to 4In the organic electroluminescent device 10 of the illustrated embodiment, the electron transport region ETR may be disposed on the light emitting layer EML. The electron transport region ETR may include at least one of a hole blocking layer HBL, an electron transport layer ETL, or an electron injection layer EIL. However, the embodiments of the present disclosure are not limited thereto.

[0271] The electron transport region ETR may have a single layer formed of a single material, a single layer formed of a plurality of different materials, or a multi-layer structure having a plurality of layers formed of a plurality of different materials.

[0272] For example, the electron transport region ETR may have a single layer structure of an electron injection layer EIL or an electron transport layer ETL, or a single layer structure formed of an electron injection material and an electron transport material. In certain embodiments, the electron transport region ETR may have a single layer structure formed of a plurality of different materials, or a structure stacked by the light emitting layer EML of the electron transport layer ETL / electron injection layer EIL or the hole blocking layer HBL / electron transport layer ETL / electron injection layer EIL, without limitation. For example, the thickness of the electron transport region ETR may be about to about

[0273] The electron transport region ETR may be formed using one or more suitable methods, such as vacuum deposition, spin coating, casting, Langmuir-Blodgett (LB) method, inkjet printing, laser printing, and / or laser induced thermal imaging (LITI) method.

[0274] If the electron transport region (ETR) includes an electron transport layer (ETL), the ETR may include an anthracene-based compound. Embodiments of the present disclosure are not limited thereto, but the ETR may contain, for example, tris(8-hydroxyquinoline) aluminum (Alq3), 1,3,5-tris[(3-pyridinyl)-phenyl-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-biphenyl)-4-phenyl-5-tert-butylphenyl-1,2,4-triazole (TAZ), 4-(naphthalen-1-yl)-3,5-diphenyl-4H-1,2,4-triazole (NTAZ), 2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (tBu-PBD), bis(2-methyl-8-hydroxyquinolinato-N1,O8)-(1,1'-biphenyl-4-olato)aluminum (BAlq), bis(10-hydroxybenzo[h]quinolinato)beryllium (Bebq2), 9,10-bis(naphthalen-2-yl)anthracene (ADN), 1,3-bis[3,5-bis(pyridin-3-yl)phenyl]benzene (BmPyPhB), or mixtures thereof. The thickness of the ETL may be from about to about and may be, for example, about to about When the thickness of the ETL satisfies the above range, satisfactory (or appropriate) electron transport performance can be obtained without significantly increasing the driving voltage.

[0275] If the ETR includes an electron injection layer (EIL), the ETR may use metal halides (such as LiF, NaCl, CsF, RbCl, and / or RbI), metals in the lanthanide series (such as Yb), metal oxides (such as Li2O and / or BaO), and / or lithium 8-hydroxyquinolate (LiQ). However, embodiments of the present disclosure are not limited thereto. The EIL may also be formed using a mixed material of an electron injection material and an insulating organic metal salt. The organic metal salt may be a material having a band gap of about 4 eV or greater. In certain embodiments, the organic metal salt may include, for example, metal acetates, metal benzoates, metal acetoacetates, metal acetylacetonates, and / or metal stearates. The thickness of the EIL may be from about to about or about to about When the thickness of the electron injection layer EIL satisfies the above range, satisfactory (or appropriate) electron injection performance can be obtained without inducing a significant increase in the driving voltage.

[0276] The electron transport region ETR may include the hole blocking layer HBL as described above. The hole blocking layer HBL may contain at least one of, for example, 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) or 4,7-diphenyl-1,10-phenanthroline (Bphen). However, the embodiments of the present disclosure are not limited thereto.

[0277] The second electrode EL2 may be disposed on the electron transport region ETR. The second electrode EL2 may be a common electrode and / or a cathode. The second electrode EL2 may be a transmissive electrode, a semi-transmissive and semi-reflective electrode, or a reflective electrode. If the second electrode EL2 is a transmissive electrode, the second electrode EL2 may be formed using a transparent metal oxide such as ITO, IZO, ZnO, ITZO, etc.

[0278] If the second electrode EL2 is a semi-transmissive and semi-reflective electrode or a reflective electrode, the second electrode EL2 may contain Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF / Ca, LiF / Al, Mo, Ti, their compounds, or their mixtures (e.g., a mixture of Ag and Mg). In certain embodiments, the second electrode EL2 may have a multilayer structure, which includes a reflective layer or a semi-transmissive and semi-reflective layer formed using any of the above materials, and a transparent conductive layer formed using ITO, IZO, ZnO, ITZO, etc.

[0279] In certain embodiments, the second electrode EL2 may be connected to an auxiliary electrode. If the second electrode EL2 is connected to the auxiliary electrode, the resistance of the second electrode EL2 may be reduced.

[0280] On the second electrode EL2 of the organic electroluminescent device 10 of the embodiment, a cover layer CPL may be further disposed. For example, the cover layer CPL may contain 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(carbazol-9-yl)triphenylamine (TCTA), N,N'-bis(naphthalen-1-yl), etc.

[0281] As a material for the organic electroluminescent device 10, the above-described compound of the embodiment may be included in a functional layer other than the hole transport region HTR. The organic electroluminescent device 10 according to an embodiment of the present disclosure may include any of the above compounds in at least one functional layer between the first electrode EL1 and the second electrode EL2 and / or in the cover layer CPL on the second electrode EL2.

[0282] In the organic electroluminescent device 10, according to the voltages applied to the first electrode EL1 and the second electrode EL2, respectively, holes injected from the first electrode EL1 move to the light-emitting layer EML via the hole transport region HTR, and electrons injected from the second electrode EL2 move to the light-emitting layer EML through the electron transport region ETR. Electrons and holes recombine in the light-emitting layer EML to generate excitons, and the excitons emit light through the transition from the excited state to the ground state.

[0283] Hereinafter, the compound according to the present embodiment and the organic electroluminescent device including the compound will be specifically explained with reference to embodiments and comparative embodiments. The following embodiments are merely for helping to understand the present disclosure, and the scope of the present disclosure is not limited thereto.

[0284] 1. Fabrication and Evaluation of Organic Electroluminescent Devices According to Embodiments

[0285] 1-1. Examples of Organic Electroluminescent Devices Containing First to Fourth Compounds

[0286] (Fabrication of Organic Electroluminescent Devices)

[0287] The organic electroluminescent devices of Examples 1 to 30 and Comparative Examples 1 to 27 were fabricated as follows. A glass substrate with ITO deposited thereon was cut into a size of about 50 mm × 50 mm × 0.5 mm, ultrasonically cleaned with isopropyl alcohol and distilled water for 10 minutes each, cleaned by exposure to ultraviolet light and then ozone for about 10 minutes, and then mounted in a vacuum deposition apparatus. Then, a hole injection layer HIL with a thickness of about was formed using 2-MTDATA, and a hole transport layer HTL with a thickness of about was formed using NPB. Thereafter, the first compound, the second compound, the third compound, and the fourth compound of the present embodiment were co-deposited in a weight ratio of 44.5:44.5:10:1 to form a light-emitting layer EML with a thickness of about A thickness of about An electron transport layer ETL with a thickness of about was formed using the compound ETL1. Then, a second electrode EL2 with a thickness of about was formed using Al. Each layer was formed by a vacuum deposition method.

[0288]

[0289] The combinations of materials for the light-emitting layer used in the examples and comparative examples are shown in Table 2 below.

[0290] Table 2

[0291]

[0292]

[0293]

[0294] (Evaluation of the performance of organic electroluminescent devices)

[0295] The performance of the organic electroluminescent device was evaluated using a luminance light distribution characteristic measurement system. To evaluate the performance of the organic electroluminescent devices according to the examples and comparative examples, the driving voltage, luminance, efficiency, emission wavelength, and lifetime (T 90 ) were measured. In Table 3, the luminous efficiency of the thus fabricated organic electroluminescent device at a current density of about 10 mA / cm 2 and a luminance of about 1000 cd / m 2 is shown. In addition, the device lifetime (T 90 ), which is the time required to reduce the luminance from a standard of 1000 cd / m 2 to 90% level, is also shown. The device lifetime (T 2 ) was measured by continuously driving at a current density of about 10 mA / cm 90 , and its unit is hours. In some embodiments, the luminance spectra of the examples and comparative examples were measured by a spectroradiometer. From the spectra thus measured, the emission peak, i.e., the maximum emission wavelength, was measured.

[0296] Table 3

[0297]

[0298]

[0299]

[0300] Referring to the results in Table 3, the first compound to the fourth compound according to the embodiments of the present disclosure are materials for the light-emitting layer EML that emit blue light, and when applied to the organic electroluminescent device 10, high efficiency and long lifetime of the device can be achieved.

[0301] Referring to the results of Examples 1 to 30 and Comparative Examples 1 to 27, it can be found that, compared with the Comparative Examples, the Examples containing the first compound represented by Formula 1, the second compound represented by Formula 2, the third compound represented by Formula 3, and the fourth compound represented by Formula 4 as the light-emitting layer materials achieved higher efficiency and longer lifetime. The Comparative Examples do not contain one or both of the first compound and the second compound, or do not contain one or both of the third compound and the fourth compound.

[0302] More specifically, when compared with Comparative Examples 1 to 23 that do not contain the first compound and / or the second compound, Examples 1 to 30 containing all of the first to fourth compounds showed better device lifetime and luminous efficiency. Without being bound by any particular theory, it is believed that since the light-emitting layer contains both the first compound having excellent hole-transporting properties and the second compound having excellent electron-transporting properties at the same time, the charge balance in the light-emitting layer can be improved, and the energy transfer from the host compound to the dopant compound can proceed smoothly.

[0303] Furthermore, when compared with Comparative Examples 24 to 27 that do not contain the third compound and / or the fourth compound, Examples 1 to 30 containing all of the first to fourth compounds showed better device lifetime and luminous efficiency. It is believed that since the light-emitting layer contains both the third compound used as an auxiliary dopant and the fourth compound used as a light-emitting dopant at the same time, delayed fluorescence can be quickly achieved using the energy transferred from the host, and the device efficiency can be improved.

[0304] When the organic electroluminescent device 10 of the Example includes the first compound and the second compound as the host, the charge balance performance in the light-emitting layer EML is improved. Furthermore, when the organic electroluminescent device 10 of the embodiment contains the third compound as an auxiliary dopant and the fourth compound as a light-emitting dopant, the emission of thermally activated fluorescence is effectively achieved, and high efficiency and long lifetime of the device are realized.

[0305] The organic electroluminescent device 10 of the embodiment contains the first compound represented by Formula 1, the second compound represented by Formula 2, the third compound represented by Formula 3, and the fourth compound represented by Formula 4. Therefore, the organic electroluminescent device 10 of the embodiment can achieve high efficiency and long lifetime.

[0306] The organic electroluminescent device according to an embodiment of the present disclosure can achieve high efficiency and long lifetime.

[0307] As used herein, the terms "using", "being used", and "having been used" may be considered synonymous with the terms "utilizing", "being utilized", and "having been utilized", respectively.

[0308] In addition, the terms "substantially", "about" and similar terms are used as approximation terms and not as terms of degree, and are intended to account for the inherent variations in measured or calculated values that would be recognized by a person of ordinary skill in the art.

[0309] In addition, any numerical range recited herein is intended to include all sub-ranges of the same numerical precision within the recited range. For example, a range of "1.0 to 10.0" is intended to include all sub-ranges between (and including) the recited minimum value of 1.0 and the recited maximum value of 10.0, i.e., the minimum value equal to or greater than 1.0 and the maximum value equal to or less than 10.0, such as, for example, 2.4 to 7.6. Any maximum numerical limitation recited herein is intended to include all lesser numerical limitations subsumed therein, and any minimum numerical limitation recited in this specification is intended to include all greater numerical limitations subsumed therein. Accordingly, the applicant reserves the right to amend this specification (including the claims) to expressly recite any sub-ranges that are included within the ranges expressly recited herein.

[0310] Although the exemplary embodiments of the present disclosure have been described, it should be understood that the present disclosure should not be limited to these exemplary embodiments, but that various changes and modifications can be made by a person of ordinary skill in the art within the spirit and scope of the present disclosure as claimed in the appended claims and their equivalents.

Claims

1. An organic electroluminescent device, comprising: a first electrode; a second electrode on the first electrode; and a light-emitting layer between the first electrode and the second electrode, wherein the light-emitting layer contains a host compound and a dopant compound, the host compound contains a first host compound represented by Formula 1 and a second host compound represented by Formula 2, and the dopant compound contains an auxiliary dopant compound represented by Formula 3 and a light-emitting dopant compound represented by Formula 4: Formula 3 Formula 4 wherein, in Formula 1, R1 and R2 are each independently a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 30 ring carbon atoms, L1 is a substituted or unsubstituted arylene group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroarylene group having 3 to 30 ring carbon atoms, Ar1 is a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 30 ring carbon atoms, and a and b are each independently an integer from 0 to 4, in Formula 2, Z1 to Z3 are each independently CR 11 or N, and Multiple Rs 11 and multiple Rs 12 Each independently is a hydrogen atom, a deuterium atom, a cyano group, a substituted silyl group, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 30 ring carbon atoms. in Formula 3, A1 to A4 are each independently a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 1 to 30 ring carbon atoms, X1 to X4 are each independently C or N, R 21 to R 24 each independently represents a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a substituted or unsubstituted amino group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 1 to 30 ring-forming carbon atoms, and any one of R 21 to R 24 optionally combines with an adjacent group to form a ring d1 to d4 are each independently an integer from 0 to 4, L 21 to L 23 each independently represents a direct bond, *-O-*, *-S-*, a substituted or unsubstituted divalent alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted arylene group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroarylene group having 2 to 30 ring carbon atoms, R 25 to R 27 each independently is a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 30 ring-forming carbon atoms, and any one of R 25 to R 27 optionally combines with an adjacent group to form a ring d5 is an integer from 0 to 8, M is platinum, palladium, copper, osmium, iridium, rubidium or rhodium, e1 to e3 are each independently 0 or 1, and m is 1 or 2, when M is platinum, palladium, copper or osmium, m is 1, and when M is iridium, rubidium or rhodium, m is 2, and e2 is 0, and in Formula 4, R 31 to R 41 each independently is a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted silyl group, a substituted or unsubstituted amino group, a substituted or unsubstituted carbonyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 30 ring carbon atoms.

2. The organic electroluminescent device according to claim 1, wherein, L1 is a substituted or unsubstituted phenylene group, a substituted or unsubstituted divalent biphenyl group, or a substituted or unsubstituted carbazolyl group.

3. The organic electroluminescent device according to claim 1, wherein, Ar1 is a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted dibenzofuranyl group, a substituted or unsubstituted dibenzothiophenyl group, or a substituted or unsubstituted biphenyl group.

4. The organic electroluminescent device according to claim 1, wherein, Formula 2 is represented by the following Formula 2-1 or Formula 2-2: Formula 2-1 Formula 2-2 wherein, in Formula 2-1, Multiple Rs 12 Each independently is a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 30 ring carbon atoms, wherein, in Formula 2-2, Multiple Rs 11 and multiple Rs 12 each independently represents a hydrogen atom, a deuterium atom, a cyano group, a substituted silyl group, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 30 ring carbon atoms, and Selected from multiple Rs 11 and multiple Rs 12 At least one of them is a cyano group, an aryl group having 6 to 30 ring-forming carbon atoms containing at least one cyano group as a substituent, or a heteroaryl group having 3 to 20 ring-forming carbon atoms containing at least one cyano group as a substituent.

5. The organic electroluminescent device according to claim 1, wherein, Formula 3 is represented by the following Formula 3-1: Formula 3-1 wherein, in Formula 3-1, A1 to A4, X1 to X4, R 21 to R 24 、d1 to d4 and L 22 are the same as those defined in Formula 3.

6. The organic electroluminescent device according to claim 1, wherein, Formula 3 is represented by the following Formula 3-2: Formula 3-2 wherein, in Formula 3-2, A1 to A4, X1 to X4, R 21 to R 24 , and d1 to d4 are the same as defined in Formula 3.

7. The organic electroluminescent device according to claim 1, wherein, Formula 4 is represented by the following Formula 4-1: Formula 4-1 wherein, in Formula 4-1, R 32 、R 33 、R 36 、R 37 and R 40 each independently represents a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted silyl group, a substituted or unsubstituted amino group, a substituted or unsubstituted carbonyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 30 ring carbon atoms, and at least one selected from R 32 、R 33 、R 36 、R 37 and R 40 is not a hydrogen atom.

8. The organic electroluminescent device according to claim 1, wherein, the light-emitting layer emits blue light as delayed fluorescence.

9. The organic electroluminescent device according to claim 1, wherein, Based on the total weight of the first host compound, the second host compound, the auxiliary dopant compound and the light-emitting dopant compound, the amount of the auxiliary dopant compound is 10 wt% to 15 wt%, and the amount of the light-emitting dopant compound is 1 wt% to 5 wt%.

10. The organic electroluminescent device according to claim 1, wherein, Based on the total weight of the host compound, the weight ratio of the first host compound to the second host compound is 7:3 to 3:

7.

11. The organic electroluminescent device according to claim 1, wherein, The first host compound includes at least one selected from the compounds represented in Compound Group 1: Compound Group 1 12. The organic electroluminescent device according to claim 1, wherein, The second host compound includes at least one selected from the compounds represented in Compound Group 2-1 and Compound Group 2-2: Compound group 2-1 Compound group 2-2 13. The organic electroluminescent device according to claim 1, wherein, The auxiliary dopant compound includes at least one selected from the compounds represented in compound group 3-1: Compound group 3-1 14. The organic electroluminescent device according to claim 1, wherein, The auxiliary dopant compound includes at least one selected from the compounds represented in compound group 3-2: Compound group 3-2 Among compounds D2-1 to D2-4, D2-13 to D2-16, and D2-25 to D2-28, one or more Rs are each independently a hydrogen atom, a methyl group, an isopropyl group, a tert-butyl group, or a dimethylamino group.

15. The organic electroluminescent device according to claim 1, wherein, The luminescent dopant compound includes at least one selected from the compounds represented in compound group 4 and formula 4-2: Compound group 4 Formula 4-2 Wherein, in formula 4-2, R 32 and R 36 is a hydrogen atom, and R 33 and R 37 are each independently a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted benzofurocarbazolyl group, a substituted or unsubstituted thiophenocarbazolyl group, a substituted or unsubstituted indolocarbazolyl group, a substituted or unsubstituted bi-carbazolyl group, a substituted or unsubstituted monoamino group, a substituted or unsubstituted diamino group, a substituted or unsubstituted acridinyl group, a substituted or unsubstituted phenoxazinyl group, or a substituted or unsubstituted phenothiazinyl group, or R 33 and R 37 is a hydrogen atom, and R 32 and R 36 are each independently a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted benzofurocarbazolyl group, a substituted or unsubstituted thiophenocarbazolyl group, a substituted or unsubstituted indolocarbazolyl group, a substituted or unsubstituted bi-carbazolyl group, a substituted or unsubstituted monoamino group, a substituted or unsubstituted diamino group, a substituted or unsubstituted acridanyl group, a substituted or unsubstituted phenoxazinyl group, or a substituted or unsubstituted phenothiazinyl group.

Images