Light emitting element and display device including the same

Abstract

Embodiments provide a light emitting element and a display device including the same. The light-emitting element includes: a first electrode; a first emission layer disposed on the first electrode and including a (1-1) th compound; a second emission layer disposed on the first emission layer and including a (2-1) th compound; and a second electrode disposed on the second emission layer, in which the (2-1) th compound has a lowest excitation triplet level (T1) in a range of about 1.5 eV to about 2.1 eV. The (1-1) th compound is represented by Formula 1, the (2-1) th compound is represented by Formula 2, and Formula 1 and Formula 2 are each described in the specification. [Formula 1] # imgabs0 # [Formula 2] # imgabs1 #

Description

[0001] Cross - reference to related applications

[0002] This application claims priority and the benefit of Korean Patent Application No. 10 - 2024 - 0004578, filed with the Korean Intellectual Property Office on January 11, 2024, the entire content of which is incorporated herein by reference. Technical field

[0003] The present disclosure relates to a light - emitting element and a display device including the light - emitting element. Background art

[0004] The development of organic electroluminescent displays as image displays is ongoing. Unlike liquid crystal displays, organic electroluminescent displays are so - called self - emissive displays, in which holes and electrons injected from a first electrode and a second electrode, respectively, recombine in an emission layer so that a light - emitting material including an organic compound in the emission layer emits light to achieve display.

[0005] When applying organic electroluminescent elements to display devices, there is a continuous need for organic electroluminescent elements having a low driving voltage, high luminous efficiency, and long service life. There is a continuous need to develop materials for organic electroluminescent elements that can stably achieve these characteristics.

[0006] To implement efficient organic electroluminescent elements, technologies involving phosphorescent emission using the lowest excited triplet energy level, or technologies involving fluorescence using triplet - triplet annihilation (TTA), in which singlet excitons are generated by the collision of triplet excitons, are being developed. Current research and development involve thermally activated delayed fluorescence (TADF) materials using the delayed fluorescence phenomenon.

[0007] It should be understood that this background art section is intended to provide useful background for understanding the technology. However, this background art section may also include ideas, concepts, or knowledge of parts that were not known or understood by those skilled in the art before the effective filing date corresponding to the subject matter disclosed herein. Summary of the invention

[0008] The present disclosure provides a light - emitting element in which luminous characteristics and the service life of the element (also referred to as the service life) are improved.

[0009] The present disclosure also provides a display device including the light - emitting element, in which luminous efficiency and service life are improved, thereby having excellent display quality.

[0010] According to an embodiment, the light-emitting element may include: a first electrode; a first emission layer disposed on the first electrode and including a compound of formula (1-1); a second emission layer disposed on the first emission layer and including a compound of formula (2-1); and a second electrode disposed on the second emission layer, wherein the compound of formula (2-1) may have a lowest excited triplet energy level (T1) in the range of about 1.5 eV to about 2.1 eV:

[0011] [Formula 1]

[0012]

[0013] In Formula 1, R1 to R 11 may each independently be a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a hydroxyl group, a substituted or unsubstituted oxy group, a substituted or unsubstituted thio group, a substituted or unsubstituted seleno group, a substituted or unsubstituted telluro group, a substituted or unsubstituted boro group, a substituted or unsubstituted silyl group, a substituted or unsubstituted amino 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 aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring carbon atoms, or bonded to an adjacent group to form a ring; X1 to X6 may each independently be a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a hydroxyl group, a substituted or unsubstituted oxy group, a substituted or unsubstituted thio group, a substituted or unsubstituted silyl group, a substituted or unsubstituted amino 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 aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring carbon atoms, or bonded to an adjacent group to form a ring; n1, n3, n4, and n6 may each independently be an integer selected from 0 to 5; and n2 and n5 may each independently be an integer selected from 0 to 3.

[0014] [Formula 2]

[0015]

[0016] In Formula 2, X may be O, S, Se, or Te; Ar may be a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms or a substituted or unsubstituted heteroaryl group having 2 to 30 ring carbon atoms; R 12 to R 17 and R x1 to R x3may each independently be a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a hydroxyl group, a substituted or unsubstituted silyl 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 2 to 30 ring carbon atoms; R y1 、R y2 and R z1 may each independently be a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a hydroxyl group, a substituted or unsubstituted amino 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 aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring carbon atoms, or bonded to an adjacent group to form a ring; x1 and x3 may each independently be an integer selected from 0 to 5; x2 may be an integer selected from 0 to 3; and y1, y2, and z1 may each independently be an integer selected from 0 to 4.

[0017] In an embodiment, the light-emitting element may further include a hole transport region disposed between the first electrode and the first emission layer; and an electron transport region disposed between the second emission layer and the second electrode.

[0018] In an embodiment, the first emission layer may emit fluorescence by thermally activated delayed fluorescence (TADF), and the second emission layer may emit fluorescence by triplet-triplet annihilation (TTA).

[0019] In an embodiment, the second emission layer may be directly disposed on the first emission layer, and the first emission layer and the second emission layer may each independently emit fluorescence having a central wavelength in the range of about 430 nm to about 490 nm.

[0020] In an embodiment, the (1-1) compound may have a lowest excited triplet energy level (T1) in the range of about 2.5 eV to about 3.1 eV.

[0021] In an embodiment, the first emission layer may include a first light-emitting host, and a first light-emitting dopant doped into the first light-emitting host and including the (1-1) compound; the second emission layer may include a second light-emitting host, and a second light-emitting dopant doped into the second light-emitting host and including the (2-1) compound; and the material included in the first light-emitting host may be different from the material included in the second light-emitting host.

[0022] In an embodiment, the first emission layer may further include at least one of the (1-2) compound represented by formula HT-1, the (1-3) compound represented by formula ET-1, and the (1-4) compound represented by formula D-1:

[0023] [Formula HT-1]

[0024]

[0025] In Formula HT-1, A1 to A8 may each independently be N or C(R 51 ); L1 may be a direct bond, a substituted or unsubstituted arylene having 6 to 30 ring carbon atoms or a substituted or unsubstituted heteroarylene having 2 to 30 ring carbon atoms; Y a may be a direct bond, C(R 52 )(R 53 ) or Si(R 54 )(R 55 ); Ar1 may be a substituted or unsubstituted aryl having 6 to 30 ring carbon atoms or a substituted or unsubstituted heteroaryl having 2 to 30 ring carbon atoms, and R 51 to R 55 may each independently be a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a substituted or unsubstituted silyl group, a substituted or unsubstituted thio group, a substituted or unsubstituted oxy group, a substituted or unsubstituted amino group, a substituted or unsubstituted boron 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 aryl group having 6 to 60 ring carbon atoms or a substituted or unsubstituted heteroaryl group having 2 to 60 ring carbon atoms, or bonded to an adjacent group to form a ring.

[0026] [Formula ET-1]

[0027]

[0028] In Formula ET-1, at least one of X1 to X3 may each be N; the remainder of X1 to X3 may each independently be C(R 56 ); R 56 may be a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 60 ring carbon atoms or a substituted or unsubstituted heteroaryl group having 2 to 60 ring carbon atoms; b1 to b3 may each independently be an integer selected from 0 to 10; Ar2 to Ar4 may each independently be a hydrogen atom, a deuterium atom, 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 2 to 30 ring carbon atoms; and L2 to L4 may each independently be a direct bond, a substituted or unsubstituted arylene having 6 to 30 ring carbon atoms or a substituted or unsubstituted heteroarylene having 2 to 30 ring carbon atoms.

[0029] [Formula D-1]

[0030]

[0031] In Formula D-1, Q1 to Q4 may each independently be C or N; C1 to C4 may each independently be a substituted or unsubstituted hydrocarbon ring group having 5 to 30 ring carbon atoms or a substituted or unsubstituted heterocyclic group having 2 to 30 ring carbon atoms; L 11 to L 13 may each independently be a direct bond, *—O—*, *—S—*, a substituted or unsubstituted alkylene 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, —* represents a bond to one of C1 to C4; c1 to c3 may each independently be 0 or 1; R 61 to R 66 may each independently be a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a substituted or unsubstituted silyl group, a substituted or unsubstituted thio group, a substituted or unsubstituted oxy group, a substituted or unsubstituted amino group, a substituted or unsubstituted boron 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 aryl group having 6 to 60 ring carbon atoms or a substituted or unsubstituted heteroaryl group having 2 to 60 ring carbon atoms, or bonded to an adjacent group to form a ring; and d1 to d4 may each independently be an integer selected from 0 to 4.

[0032] In an embodiment, the first emission layer may include the (1-1) compound, the (1-2) compound, the (1-3) compound, and the (1-4) compound.

[0033] In an embodiment, the second emission layer may further include the (2-2) compound represented by Formula E-1:

[0034] [Formula E-1]

[0035]

[0036] In Formula E-1, R 31 to R 40Each may independently be a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted silyl group, a substituted or unsubstituted thio group, a substituted or unsubstituted oxy group, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring carbon atoms, or bonded to an adjacent group to form a ring.

[0037] In an embodiment, the second emission layer may be composed of the compound (2-1) and the compound (2-2).

[0038] In an embodiment, the compound (1-1) may be represented by one of Formulae 1-1 to 1-3:

[0039] [Formula 1-1]

[0040]

[0041] [Formula 1-2]

[0042]

[0043] [Formula 1-3]

[0044]

[0045] In Formulae 1-1 to 1-3, Y1 to Y8, Z1, and Z2 may each independently be a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a hydroxy group, a substituted or unsubstituted oxy group, a substituted or unsubstituted thio group, a substituted or unsubstituted seleno group, a substituted or unsubstituted telluro group, a substituted or unsubstituted germanium group, a substituted or unsubstituted boron group, a substituted or unsubstituted silyl group, a substituted or unsubstituted amino 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 aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring carbon atoms, or bonded to an adjacent group to form a ring; m1 to m8 may each independently be an integer selected from 0 to 4; p1 and p2 may each independently be an integer selected from 0 to 5; and R1, R3 to R 11 , X1 to X6, and n1 to n6 may be the same as defined in Formula 1.

[0046] In an embodiment, the compound (1-1) may be represented by Formula 1-4:

[0047] [Formula 1-4]

[0048]

[0049] In Formulas 1-4, Q1 and Q2 may each independently be O, S, Se, Te, or N(R 30 ); R 21 to R 30 may each independently be a hydrogen atom, a deuterium atom, a halogen atom, a cyano 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 aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring carbon atoms, or bonded to an adjacent group to form a ring; and R5 to R 11 , X1 to X6, and n1 to n6 may be the same as defined in Formula 1.

[0050] In an embodiment, the compound of (1-1) may be represented by one of Formulas 1-5 to 1-11:

[0051] [Formula 1-5]

[0052]

[0053] [Formula 1-6]

[0054]

[0055] [Formula 1-7]

[0056]

[0057] [Formula 1-8]

[0058]

[0059] [Formula 1-9]

[0060]

[0061] [Formula 1-10]

[0062]

[0063] [Formula 1-11]

[0064]

[0065] In Formulas 1-5 to 1-11, R1 to R 11 may be the same as defined in Formula 1.

[0066] In an embodiment, in Formula 1, R 10 may be a group represented by one of Formulas 3-1 to 3-6: [Formula 3-1]

[0067]

[0068] [Formula 3-2]

[0069]

[0070] [Formula 3-3]

[0071]

[0072] [Formula 3-4]

[0073]

[0074] [Formula 3-5]

[0075]

[0076] [Formula 3-6]

[0077]

[0078] In Formulas 3-1 to 3-6, *— represents a bond with Formula 1, and D represents a deuterium atom.

[0079] In an embodiment, in Formula 2, R 16 , R y1 , R y2 , R z1 and at least one of Ar may each independently be a group represented by one of Formulas 4-1 to 4-4:

[0080] [Formula 4-1]

[0081]

[0082] [Formula 4-2]

[0083]

[0084] [Formula 4-3]

[0085]

[0086] [Formula 4-4]

[0087]

[0088] In Formulas 4-1 to 4-4, L1 to L4 may each independently be a direct bond or a substituted or unsubstituted arylene having 6 to 30 ring carbon atoms; R a1 to R a4may each independently be a hydrogen atom, a deuterium atom, 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 2 to 30 ring carbon atoms, or bonded to an adjacent group to form a ring; a1 and a2 may each independently be an integer selected from 0 to 9; a3 may be an integer selected from 0 to 7; a4 may be an integer selected from 0 to 8, and *— represents a bond to formula 2.

[0089] In an embodiment, in formulas 4-1 to 4-4, L1 to L4 may each independently be a direct bond, a substituted or unsubstituted phenylene group, or a substituted or unsubstituted biphenylene group; and R a1 to R a4 may each independently be a hydrogen atom or a substituted or unsubstituted phenyl group.

[0090] In an embodiment, the compound of (2-1) may be represented by formula 2-1:

[0091] [Formula 2-1]

[0092]

[0093] In the above formula 2-1, R b1 may be a hydrogen atom, a deuterium atom, 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 aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring carbon atoms; at least one of R y1 , R y2 , R z1 and R b1 may each independently be a group represented by one of formulas 4-1 to 4-4; b1 may be an integer selected from 0 to 5; and X, R 12 to R 17 , R x1 to R x3 , R y1 , R y2 , R z1 , x1 to x3, y1, y2 and z1 may be the same as those defined in formula 2.

[0094] In an embodiment, the compound of (2-1) may be represented by one of formulas 2-2 to 2-4:

[0095] [Formula 2-2]

[0096]

[0097] [Formula 2-3]

[0098]

[0099] [Formula 2-4]

[0100]

[0101] In Formulas 2-2 to 2-4, R b2 to R b8 may each independently be a hydrogen atom, a deuterium atom, 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 aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring carbon atoms; b2 may be an integer selected from 0 to 5; X, Ar, R 12 to R 15 , R 17 , R x1 to R x3 , R y1 , R y2 , R z1 , x1 to x3, y1, y2 and z1 may be the same as defined in Formula 2. When the compound (2-1) is represented by Formula 2-2, at least one of R y1 , R y2 , R z1 and R b2 may each independently be a group represented by one of Formulas 4-1 to 4-4; when the compound (2-1) is represented by Formula 2-3, at least one of R y1 , R y2 , R z1 , R b3 , R b4 and R b5 may each independently be a group represented by one of Formulas 4-1 to 4-4; and when the compound (2-1) is represented by Formula 2-4, at least one of R y1 , R y2 , R z1 , R b6 , R b7 and R b8 may each independently be a group represented by one of Formulas 4-1 to 4-4.

[0102] In an embodiment, the compound (2-1) may be represented by Formula 2-5:

[0103] [Formula 2-5]

[0104]

[0105] In Formula 2-5, R b9 and Rb10 may each independently be a hydrogen atom, a deuterium atom, a substituted or unsubstituted silyl group, a substituted or unsubstituted amino 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 aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring carbon atoms, or bonded to an adjacent group to form a ring; R y1 、R y2 、R b9 and R b10 at least one of may each independently be a group represented by one of Formulae 4-1 to 4-4; and X, Ar, R 12 to R 17 、R x1 to R x3 、R y1 、R y2 、x1 to x3, y1 and y2 may be the same as defined in Formula 2.

[0106] In an embodiment, the (2-1) compound may be represented by one of Formulae 2-6 to 2-8:

[0107] [Formula 2-6]

[0108]

[0109] [Formula 2-7]

[0110]

[0111] [Formula 2-8]

[0112]

[0113] In Formulae 2-6 to 2-8, X, Ar, R 12 to R 17 、R x1 to R x3 、R y1 、R y2 、R z1 、x1 to x3, y1, y2 and z1 may be the same as defined in Formula 2.

[0114] In an embodiment, the (1-1) compound may include at least one compound selected from Compound Group 1-1 explained below.

[0115] In an embodiment, the (2-1) compound may include at least one compound selected from Compound Group 2-1 explained below.

[0116] According to an embodiment, a display device may include a circuit layer disposed on a base layer; and a display element layer disposed on the circuit layer and including a light-emitting element, wherein

[0117] The light-emitting element may include a first electrode; a first emission layer disposed on the first electrode and including a (1-1) compound represented by Formula 1; a second emission layer disposed on the first emission layer and including a (2-1) compound represented by Formula 2; and a second electrode disposed on the second emission layer, and the (2-1) compound may have a lowest excited triplet energy level (T1) in the range of about 1.5 eV to about 2.1 eV.

[0118] It should be understood that the above embodiments are described only in a general and illustrative sense and not for the purpose of limitation, and the present disclosure is not limited to the above embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0119] The accompanying drawings are included to provide a further understanding of the embodiments, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the present disclosure and their principles. The above and other aspects and features of the present disclosure will become more apparent by describing embodiments of the present disclosure in detail with reference to the accompanying drawings, in which:

[0120] Figure 1 is a schematic plan view of a display device according to an embodiment;

[0121] Figure 2 is a schematic cross-sectional view of a part of a display device according to an embodiment;

[0122] Figure 3 is a schematic cross-sectional view of a light-emitting element according to an embodiment;

[0123] Figure 4 is a schematic cross-sectional view of a light-emitting element according to an embodiment;

[0124] Figure 5 is a schematic cross-sectional view of a light-emitting element according to an embodiment;

[0125] Figure 6 is a schematic cross-sectional view of a light-emitting element according to an embodiment;

[0126] Figure 7 is a schematic cross-sectional view of a display device according to an embodiment;

[0127] Figure 8 is a schematic cross-sectional view of a display device according to an embodiment;

[0128] Figure 9 is a schematic cross-sectional view of a display device according to an embodiment;

[0129] Figure 10 is a schematic cross-sectional view of a display device according to an embodiment; and

[0130] Figure 11 is a schematic perspective view of a vehicle in which a display device according to an embodiment is provided. DETAILED DESCRIPTION

[0131] The present disclosure will now be described more fully hereinafter with reference to the accompanying drawings, in which embodiments are shown. However, the present disclosure may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the present disclosure to those skilled in the art.

[0132] In the drawings, for ease of description and for clarity, the dimensions (such as thickness), proportions, and dimensions of elements may be enlarged. The same reference numerals and reference characters refer to the same elements throughout.

[0133] In the specification, it will be understood that when an element (or region, layer, component, etc.) is referred to as being "on" another element (or region, layer, component, etc.), "connected to" or "coupled to" another element (or region, layer, component, etc.), it may be directly on the other element (or region, layer, component, etc.), directly connected to or directly coupled to the other element (or region, layer, component, etc.), or there may be one or more intervening elements (or regions, layers, components, etc.) therebetween. In a similar sense, when an element (or region, layer, component, etc.) is described as "covering" another element (or region, layer, component, etc.), it may directly cover the other element (or region, layer, component, etc.), or there may be one or more intervening elements (or regions, layers, components, etc.) therebetween.

[0134] In the specification, when an element is "directly on" another element, "directly connected to" or "directly coupled to" another element, there is no intervening element. For example, "directly on" may mean that two layers or two elements are provided without another element (such as an adhesive element) therebetween.

[0135] As used herein, expressions used in the singular form, such as "a", "an", and "the", are also intended to include the plural forms unless the context clearly indicates otherwise.

[0136] As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. For example, "A and / or B" can be understood to mean "A, B, or A and B". The terms "and" and "or" can be used in a conjunctive sense or a disjunctive sense and can be understood to be equivalent to "and / or".

[0137] In the specification and claims, for purposes of their meaning and interpretation, the term "at least one of..." is intended to include the meaning of "at least one selected from the group consisting of...". For example, "at least one of A, B, and C" can be understood to mean only A, only B, only C, or any combination of two or more of A, B, and C, such as ABC, ACC, BC, or CC. When following a list of elements, the term "at least one of..." modifies the entire list of elements and not a single element of the list.

[0138] It will 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, without departing from the scope of the present disclosure, a second element may be referred to as a first element.

[0139] For ease of description, spatial relative terms such as "below", "beneath", "under", "above", or "on" etc. may be used herein to describe the relationship between one element or component and another element or component as illustrated in the figures. It will be understood that, in addition to the orientation depicted in the figures, the spatial relative terms are also intended to encompass different orientations of the device in use or operation. For example, in the case of flipping the device illustrated in the figures, a device located "below" or "beneath" another device may be placed "above" the other device. Accordingly, the illustrative term "below" can include both a lower position and an upper position. The device may also be oriented in other directions, and thus the spatial relative terms may be differently interpreted depending on the orientation.

[0140] As used herein, the term "about" or "approximately" includes the recited value and means within an acceptable deviation range determined by a person of ordinary skill in the art considering the measurement in question and the errors associated with the measurement of the recited quantity (i.e., the limitations of the measurement system). For example, "about" can mean within one or more standard deviations of the recited value, or within ±20%, ±10%, or ±5% of the recited value.

[0141] It should be understood that the terms "comprises", "comprising", "includes", "including", "have", "having", "contains", and "containing" etc. are intended to indicate the presence of the recited features, integers, steps, operations, elements, components, or any combination thereof in the present disclosure, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or any combination thereof.

[0142] Unless otherwise defined or implied herein, all terms used (including technical and scientific terms) 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 that is consistent with their meaning in the context of the relevant art and should not be interpreted in an idealized or overly formal sense unless clearly defined in the specification.

[0143] In the present invention, an integer selected from 0 to 3 means an integer selected from 0, 1, 2, and 3; an integer selected from 0 to 4 means an integer selected from 0, 1, 2, 3, and 4; an integer selected from 0 to 5 means an integer selected from 0, 1, 2, 3, 4, and 5; an integer selected from 0 to 7 means an integer selected from 0, 1, 2, 3, 4, 5, 6, and 7; an integer selected from 0 to 8 means an integer selected from 0, 1, 2, 3, 4, 5, 6, 7, and 8; an integer selected from 0 to 9 means an integer selected from 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9; and an integer selected from 0 to 10 means an integer selected from 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10.

[0144] In the specification, the term "substituted or unsubstituted" may describe a group that is unsubstituted or substituted with at least one substituent selected from the group consisting of: a deuterium atom, a halogen atom, a cyano group, a nitro group, an amino group, an amine group, a silyl group, an oxy group, a thio group, a germyl 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 alkynyl group, a hydrocarbon ring group, an aryl group, and a heterocyclic group. Each of the substituents listed above may itself be substituted or unsubstituted. For example, a biphenyl group may be interpreted as an aryl group, or it may be interpreted as a phenyl group substituted with a phenyl group.

[0145] In the specification, the term "bonded to an adjacent group to form a ring" may refer to a group that is bonded to an adjacent group to form a substituted or unsubstituted hydrocarbon ring or a substituted or unsubstituted heterocyclic ring. The hydrocarbon ring may be aliphatic or aromatic. The heterocyclic ring may be aliphatic or aromatic. The hydrocarbon ring and the heterocyclic ring may each independently be monocyclic or polycyclic. The ring formed by bonding adjacent groups to each other may itself be connected to another ring to form a spiro structure.

[0146] In the specification, the term "adjacent group" may be interpreted as a substituent that substitutes an atom directly connected to an atom substituted with a corresponding substituent, as another substituent that substitutes an atom substituted with a corresponding substituent, or as a substituent that is spatially located in the position closest to the corresponding substituent. For example, the two methyl groups in 1,2 - xylene may be interpreted as "adjacent groups" to each other, and the two ethyl groups in 1,1 - diethylcyclopentane may be interpreted as "adjacent groups" to each other. For example, the two methyl groups in 4,5 - dimethylphenanthrene may be interpreted as "adjacent groups" to each other.

[0147] In the specification and claims, terms such as "(1-1)" can be understood as "first-first" and are used to improve text efficiency. The numbers in parentheses are used to replace ordinal numbers. For example, "(1-3)" can be understood as "first-third", and "(2-2)" can be understood as "second-second".

[0148] In the specification, examples of the halogen atom may include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

[0149] In the specification, the alkyl group may be straight-chain or branched-chain. 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, 1-methylpentyl, 3-methylpentyl, 2-ethylpentyl, 4-methyl-2-pentyl, n-hexyl, 1-methylhexyl, 2-ethylhexyl, 2-butylhexyl, 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, 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, etc., but the embodiments are not limited thereto.

[0150] In the specification, the cycloalkyl group may be a cyclic alkyl group. The number of carbon atoms in the cycloalkyl group may be 3 to 50, 3 to 30, 3 to 20, or 3 to 10. Examples of the cycloalkyl group may include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, 4-methylcyclohexyl, 4-tert-butylcyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, norbornyl, 1-adamantyl, 2-adamantyl, isobornyl, bicycloheptyl, etc., but the embodiments are not limited thereto.

[0151] In the specification, an alkenyl group may be a hydrocarbon group including at least one carbon-carbon double bond in the middle or at the end of an alkyl group having 2 or more carbon atoms. The alkenyl group may be straight-chain or branched-chain. The number of carbon atoms in the alkenyl group is not specifically limited and may be 2 to 30, 2 to 20, or 2 to 10. Examples of the alkenyl group may include vinyl, 1-butenyl, 1-pentenyl, 1,3-butadienyl, styryl, styrylethylene, etc., but the embodiments are not limited thereto.

[0152] In the specification, an alkynyl group may be a hydrocarbon group including at least one carbon-carbon triple bond in the middle or at the end of an alkyl group having 2 or more carbon atoms. The alkynyl group may be straight-chain or branched-chain. The number of carbon atoms in the alkynyl group is not specifically limited and may be 2 to 30, 2 to 20, or 2 to 10. Examples of the alkynyl group may include ethynyl, propynyl, etc., but the embodiments are not limited thereto.

[0153] In the specification, a hydrocarbon ring group may be any functional group or substituent derived from an aliphatic hydrocarbon ring. For example, the hydrocarbon ring group may be a saturated hydrocarbon ring group having 5 to 20 ring-forming carbon atoms.

[0154] In the specification, an aryl group may be any functional group or substituent derived from an aromatic hydrocarbon ring. The aryl group may be monocyclic or polycyclic. The number of ring-forming carbon atoms 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, anthryl, phenanthryl, biphenyl, terphenyl, quaterphenyl, quinquephenyl, sexiphenyl, triphenylene, pyrenyl, acenaphthylenyl, benzo[a]pyrenyl, 1,2-benzophenanthryl, etc., but the embodiments are not limited thereto.

[0155] In the specification, the fluorenyl group may be substituted, and two substituents may be bonded to each other to form a spiro structure. Examples of the substituted fluorenyl group may include the groups shown below. However, the embodiments are not limited thereto.

[0156]

[0157] In the specification, a heterocyclic group may be any functional group or substituent derived from a ring including at least one of B, O, N, P, Si, S, Se, and Te as a heteroatom. The heterocyclic group may be aliphatic or aromatic. The aromatic heterocyclic group may be a heteroaryl group. The aliphatic heterocyclic group and the aromatic heterocyclic group may each independently be monocyclic or polycyclic.

[0158] If the heterocyclic group includes two or more heteroatoms, the two or more heteroatoms may be the same or different from each other. The number of ring-forming carbon atoms in the heterocyclic group may be 2 to 60, 2 to 30, 2 to 20, or 2 to 10.

[0159] Examples of the aliphatic heterocyclic group may include oxiranyl, thiiranyl, pyrrolidinyl, piperidinyl, tetrahydrofuryl, tetrahydrothienyl, thianyl, tetrahydropyranyl, 1,4-dioxanyl, etc., but the embodiments are not limited thereto.

[0160] Examples of the heteroaryl group may include thienyl, furyl, pyrrolyl, imidazolyl, pyridyl, bipyridyl, pyrimidinyl, triazinyl, triazolyl, 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, benzothienocarbazolyl, benzothienoindolyl, benzo[1,2-b:4,5-b']dithiophene, thienothiophene, indolo[2,3-b]benzothiophene, benzoselenophenyl, dibenzoselenophenyl, benzoselenocarbazolyl, benzoselenoindolyl, benzotellurophenyl, dibenzotellurophenyl, benzotellurocarbazolyl, benzotelluroindolyl, benzofuryl, phenanthrolinyl, thiazolyl, isoxazolyl, oxazolyl, oxadiazolyl, thiadiazolyl, phenothiazinyl, dibenzosilolyl, dibenzofuryl, etc., but the embodiments are not limited thereto.

[0161] In the specification, the above description of the aryl group can be applied to the arylene group, provided that the arylene group is a divalent group. In the specification, the above description of the heteroaryl group can be applied to the heteroarylene group, provided that the heteroarylene group is a divalent group.

[0162] In the specification, the silyl group can be an alkylsilyl group or an arylsilyl group. The alkyl in the alkylsilyl group can be linear, branched or cyclic. The number of carbon atoms in the alkylsilyl group is not specifically limited, but can be, for example, 1 to 20 or 1 to 10. The number of carbon atoms in the arylsilyl group is not specifically limited, but can be, for example, 6 to 30, 6 to 20 or 6 to 15. Examples of the silyl group may include trimethylsilyl, triethylsilyl, tert-butyldimethylsilyl, vinyldimethylsilyl, propyldimethylsilyl, triphenylsilyl, diphenylsilyl, phenylsilyl, etc., but the embodiments are not limited thereto.

[0163] In the specification, the number of carbon atoms in the carbonyl group is not specifically limited and can be 1 to 40, 1 to 30 or 1 to 20. For example, the carbonyl group can have one of the following structures, but the embodiments are not limited thereto.

[0164]

[0165] In the specification, the number of carbon atoms in the sulfinyl or sulfonyl group is not specifically limited and may be from 1 to 30. The sulfinyl group may be an alkylsulfinyl group or an arylsulfinyl group. The sulfonyl group may be an alkylsulfonyl group or an arylsulfonyl group.

[0166] In the specification, the thio group may be an alkylthio group or an arylthio group. The thio group may be a sulfur atom bonded to an alkyl or aryl group as defined above. The alkyl group in the alkylthio group may be linear, branched, or cyclic. The number of carbon atoms in the alkylthio group is not specifically limited, but may be, for example, from 1 to 20 or from 1 to 10. The number of carbon atoms in the arylthio group is not specifically limited, but may be, for example, from 6 to 30, from 6 to 20, or from 6 to 15. Examples of the thio group may include methylthio, ethylthio, propylthio, pentylthio, hexylthio, octylthio, dodecylthio, cyclopentylthio, cyclohexylthio, phenylthio, naphthylthio, but the embodiments are not limited thereto.

[0167] In the specification, the oxy group may be an oxygen atom bonded to an alkyl or aryl group as defined above. The oxy group may be an alkoxy group or an aryloxy group. The alkoxy group may be linear, branched, or cyclic. The number of carbon atoms in the alkoxy group is not specifically limited and may be, for example, from 1 to 20 or from 1 to 10. The number of carbon atoms in the aryloxy group is not specifically limited, but may be, for example, from 6 to 30, from 6 to 20, or from 6 to 15. Examples of the oxy group may include methoxy, ethoxy, n-propoxy, isopropoxy, butoxy, pentyloxy, hexyloxy, octyloxy, nonyloxy, decyloxy, benzyloxy, etc., but the embodiments are not limited thereto.

[0168] In the specification, the boryl group may be a boron atom bonded to an alkyl or aryl group as defined above. The boryl group may be an alkylboryl group or an arylboryl group. The alkyl group in the alkylboryl group may be linear, branched, or cyclic. The number of carbon atoms in the alkylboryl group is not specifically limited, but may be, for example, from 1 to 20 or from 1 to 10. The number of carbon atoms in the arylboryl group is not specifically limited, but may be, for example, from 6 to 30, from 6 to 20, or from 6 to 15. Examples of the boryl group may include dimethylboryl, diethylboryl, tert-butylmethylboryl, diphenylboryl, phenylboryl, etc., but the embodiments are not limited thereto.

[0169] In the specification, the number of carbon atoms in the amino group is not specifically limited and may be from 1 to 30. The amino group may be an alkylamino group or an arylamino group. The alkyl group in the alkylamino group may be linear, branched, or cyclic. The number of carbon atoms in the alkylamino group is not specifically limited, but may be, for example, from 1 to 20 or from 1 to 10. The number of carbon atoms in the arylamino group is not specifically limited, but may be, for example, from 6 to 30, from 6 to 20, or from 6 to 15. Examples of the amino group may include methylamino, dimethylamino, phenylamino, diphenylamino, naphthylamino, 9-methyl-anthrylamino, etc., but the embodiments are not limited thereto.

[0170] In the specification, the seleno group may be an alkylseleno group or an arylseleno group. The seleno group may be a selenium atom bonded to an alkyl or aryl group as defined above. The number of carbon atoms in the alkylseleno group is not particularly limited, but may be, for example, 1 to 20 or 1 to 10. The number of carbon atoms in the arylseleno group is not particularly limited, but may be, for example, 6 to 30, 6 to 20 or 6 to 15. Examples of the seleno group may include methylseleno group, ethylseleno group, propylseleno group, pentylseleno group, hexylseleno group, octylseleno group, dodecylseleno group, cyclopentylseleno group, cyclohexylseleno group, phenylseleno group or naphthylseleno group, etc., but the embodiments are not limited thereto.

[0171] In the specification, the telluro group may be an alkyltelluro group or an aryltelluro group. The telluro group may be a tellurium atom bonded to an alkyl or aryl group as defined above. The number of carbon atoms in the alkyltelluro group is not particularly limited, but may be, for example, 1 to 20 or 1 to 10. The number of carbon atoms in the aryltelluro group is not particularly limited, but may be, for example, 6 to 30, 6 to 20 or 6 to 15. Examples of the telluro group may include methyltelluro group, ethyltelluro group, propyltelluro group, pentyltelluro group, hexyltelluro group, octyltelluro group, dodecyltelluro group, cyclopentyltelluro group, cyclohexyltelluro group, phenyltelluro group or naphthyltelluro group, etc., but the embodiments are not limited thereto.

[0172] In the specification, the germano group may be an alkylgermano group or an arylgermano group. The germano group may be a germanium atom bonded to an alkyl or aryl group as defined above. The number of carbon atoms in the alkylgermano group is not particularly limited, but may be, for example, 1 to 20 or 1 to 10. The number of carbon atoms in the arylgermano group is not particularly limited, but may be, for example, 6 to 30, 6 to 20 or 6 to 15. Examples of the germano group may include methylgermano group, ethylgermano group, propylgermano group, pentylgermano group, hexylgermano group, octylgermano group, dodecylgermano group, cyclopentylgermano group, cyclohexylgermano group, phenylgermano group or naphthylgermano group, etc., but the embodiments are not limited thereto.

[0173] In the specification, the sulfinyl group may mean an alkyl or aryl group as defined above bonded to -S(=O)-. The number of carbon atoms in the sulfinyl group is not particularly limited, but may be 1 to 30, 1 to 20 or 1 to 10. The sulfinyl group may include an alkylsulfinyl group and an arylsulfinyl group. For example, the sulfinyl group may have the following structures, but is not limited thereto.

[0174]

[0175] In the specification, the sulfonyl group may mean an alkyl or aryl group as defined above bonded to -S(=O)2-. The number of carbon atoms in the sulfonyl group is not particularly limited, but may be 1 to 30, 1 to 20 or 1 to 10. The sulfonyl group may include an alkylsulfonyl group and an arylsulfonyl group. For example, the sulfonyl group may have the following structures, but is not limited thereto.

[0176]

[0177] In the specification, the phosphine oxide group may mean the above-defined alkyl or aryl group bonded to -P(=O)-. The number of carbon atoms of the phosphine oxide group is not specifically limited, but may be 1 to 30, 1 to 20, or 1 to 10. The phosphine oxide group may include an alkylphosphine oxide group and an arylphosphine oxide group. For example, the phosphine oxide group may have the following structures, but is not limited thereto.

[0178]

[0179] In the specification, the phosphine sulfide group may mean the above-defined alkyl or aryl group bonded to -P(=S)-. The number of carbon atoms of the phosphine sulfide group is not specifically limited, but may be 1 to 30, 1 to 20, or 1 to 10. The phosphine sulfide group may include an alkylphosphine sulfide group and an arylphosphine sulfide group. For example, the phosphine sulfide group may have the following structures, but is not limited thereto.

[0180]

[0181] In the specification, the alkyl group in alkoxy, alkylthio, alkylsulfonyl, alkylsulfinyl, alkylaryl, alkylamino, alkylboron, alkylsilyl, alkylphosphine oxide, alkylphosphine sulfide, alkylseleno, alkyltelluro, alkylgermyl, or alkylamino group may be the same as the examples of the above alkyl group.

[0182] In the specification, the aryl group in aryloxy, arylthio, arylsulfonyl, arylamino, arylsulfinyl, arylboron, arylsilyl, arylphosphine oxide, arylphosphine sulfide, arylseleno, aryltelluro, arylgermyl, or arylamino group may be the same as the examples of the above aryl group.

[0183] In the specification, the direct bond may be a single bond.

[0184] In the specification, the symbols and ——* each represent a bond to an adjacent atom in the corresponding formula or moiety.

[0185] Hereinafter, embodiments will be described with reference to the accompanying drawings.

[0186] Figure 1 is a schematic plan view of a display device DD according to an embodiment. Figure 2 is a schematic cross-sectional view of the display device DD. Figure 2 is along Figure 1 A schematic cross-sectional view of a part of the display device DD taken along the dashed line I-I'.

[0187] The display device DD may include a display panel DP and an optical layer PP disposed on the display panel DP. The display panel DP includes light-emitting elements ED-1, ED-2, and ED-3. The display device DD may include a plurality of light-emitting elements ED-1, ED-2, and ED-3. The optical layer PP may be disposed on the display panel DP to control light reflected by external light at the display panel DP. The optical layer PP may include, for example, a polarization layer or a color filter layer. Although not shown in the drawings, in an embodiment, the optical layer PP may be omitted from the display device DD.

[0188] A base substrate BL may be disposed on the optical layer PP. The base substrate BL may provide a base surface on which the optical layer PP is disposed. The base substrate BL may be a glass substrate, a metal substrate, a plastic substrate, or the like. However, the embodiments are not limited thereto, and the base substrate BL may include an inorganic layer, an organic layer, or a composite material layer. Although not shown in the drawings, in an embodiment, the base substrate BL may be omitted.

[0189] The display device DD according to an embodiment may further include a filling layer (not shown). The filling layer (not shown) may be disposed between the display device layer DP-ED and the base substrate BL. The filling layer (not shown) may be an organic material layer. The filling layer (not shown) may include at least one of an acrylic resin, a silicone resin, and an epoxy resin.

[0190] The display panel DP may include a base layer BS, a circuit layer DP-CL provided on the base layer BS, and a display device layer DP-ED. The display device layer DP-ED may include a pixel defining film PDL, light-emitting elements ED-1, ED-2, and ED-3 disposed between a plurality of portions of the pixel defining film PDL, and a encapsulation layer TFE disposed on the light-emitting elements ED-1, ED-2, and ED-3.

[0191] The base layer BS may provide a base surface on which the display device layer DP-ED is disposed. The base layer BS may be a glass substrate, a metal substrate, a plastic substrate, or the like. However, the embodiments are not limited thereto, and the base layer BS may include an inorganic layer, an organic layer, or a composite material layer.

[0192] In an embodiment, the circuit layer DP-CL is disposed on the base layer BS, and the circuit layer DP-CL may include a plurality of transistors (not shown). The plurality of transistors (not shown) may each include a control electrode, an input electrode, and an output electrode. For example, the circuit layer DP-CL may include switching transistors and driving transistors for driving the light-emitting elements ED-1, ED-2, and ED-3 of the display device layer DP-ED.

[0193] The light-emitting elements ED-1, ED-2, and ED-3 may each have according to what will be described later Figures 3 to 6The structure of the light-emitting element ED of any one of the embodiments. The light-emitting elements ED-1, ED-2, and ED-3 may each include a first electrode EL1, a hole transport region HTR, emission layers EML-R, EML-G, and EML-B, an electron transport region ETR, and a second electrode EL2.

[0194] The emission layers EML-R, EML-G, and EML-B may include a red emission layer EML-R, a green emission layer EML-G, and a blue emission layer EML-B. The red emission layer EML-R, the green emission layer EML-G, and the blue emission layer EML-B may correspond to a red emission region PXA-R, a green emission region PXA-G, and a blue emission region PXA-B, respectively. The red emission layer EML-R may include a stacked first red emission layer EML1-R and a second red emission layer EML2-R, the green emission layer EML-G may include a stacked first green emission layer EML1-G and a second green emission layer EML2-G, and the blue emission layer EML-B may include a stacked first blue emission layer EML1-B and a second blue emission layer EML2-B. The stacked structure of the emission layers EML-R, EML-G, and EML-B will be described later in conjunction with Figure 3 the description of the stacked structure of the emission layers EML-R, EML-G, and EML-B.

[0195] Figure 2 An embodiment is illustrated in which the emission layers EML-R, EML-G, and EML-B of the light-emitting elements ED-1, ED-2, and ED-3 are disposed in the opening holes OH defined in the pixel defining film PDL, and the hole transport region HTR, the electron transport region ETR, and the second electrode EL2 are each provided as a common layer in the entire light-emitting elements ED-1, ED-2, and ED-3. However, the embodiment is not limited thereto. Although not shown in Figure 2 it, the hole transport region HTR and the electron transport region ETR may each be provided by patterning in the opening holes OH defined in the pixel defining film PDL. For example, in an embodiment, the hole transport region HTR, the emission layers EML-R, EML-G, and EML-B, and the electron transport region ETR of the light-emitting elements ED-1, ED-2, and ED-3 may each be provided by patterning through an inkjet printing method.

[0196] The encapsulation layer TFE may cover the light-emitting elements ED-1, ED-2, and ED-3. The encapsulation layer TFE may seal the light-emitting elements ED-1, ED-2, and ED-3 in the display device layer DP-ED. The encapsulation layer TFE may be a thin film encapsulation layer. The encapsulation layer TFE may be formed of a single layer or multiple layers. The encapsulation layer TFE may include at least one insulating layer. The encapsulation layer TFE according to an embodiment may include at least one inorganic film (hereinafter, encapsulation-inorganic film). The encapsulation layer TFE according to an embodiment may also include at least one organic film (hereinafter, encapsulation-organic film) and at least one encapsulation-inorganic film.

[0197] The encapsulation - inorganic film protects the display device layer DP - ED from moisture and / or oxygen, and the encapsulation - organic film protects the display device layer DP - ED from foreign substances (e.g., dust particles). The encapsulation - inorganic film may include silicon nitride, silicon oxynitride, silicon oxide, titanium oxide, aluminum oxide, etc., but the embodiments are not limited thereto. The encapsulation - organic film may include acrylic compounds or epoxy compounds, etc. The encapsulation - organic film may include a photopolymerizable organic material, but the embodiments are not limited thereto.

[0198] The encapsulation layer TFE may be disposed on the second electrode EL2 and may be disposed to fill the opening OH.

[0199] Reference Figure 1 and Figure 2 The display device DD may include a non - light - emitting area NPXA and light - emitting areas PXA - R, PXA - G, and PXA - B. The light - emitting areas PXA - R, PXA - G, and PXA - B may each be an area that emits light generated by the light - emitting elements ED - 1, ED - 2, and ED - 3, respectively. In a plan view, the light - emitting areas PXA - R, PXA - G, and PXA - B may be spaced apart from each other.

[0200] The light - emitting areas PXA - R, PXA - G, and PXA - B may be areas separated from each other by the pixel - defining film PDL. The non - light - emitting area NPXA may be an area between adjacent light - emitting areas PXA - R, PXA - G, and PXA - B and may correspond to the pixel - defining film PDL. In an embodiment, the light - emitting areas PXA - R, PXA - G, and PXA - B may each correspond to a pixel. The pixel - defining film PDL may separate the light - emitting elements ED - 1, ED - 2, and ED - 3. The emission layers EML - R, EML - G, and EML - B of the light - emitting elements ED - 1, ED - 2, and ED - 3 may be disposed in the openings OH defined in the pixel - defining film PDL and separated from each other.

[0201] According to the colors of the light generated by the light - emitting elements ED - 1, ED - 2, and ED - 3, the light - emitting areas PXA - R, PXA - G, and PXA - B may be arranged in multiple groups. In Figure 1 and Figure 2 In the display device DD according to an embodiment illustrated in, three light - emitting areas PXA - R, PXA - G, and PXA - B that emit red, green, and blue light, respectively, are illustrated as an example. For example, the display device DD may include a red light - emitting area PXA - R, a green light - emitting area PXA - G, and a blue light - emitting area PXA - B that are different from each other.

[0202] In the display device DD according to an embodiment, the light-emitting elements ED-1, ED-2, and ED-3 may emit light having wavelength ranges different from each other. For example, in an embodiment, the display device DD may include a first light-emitting element ED-1 that emits red light, a second light-emitting element ED-2 that emits green light, and a third light-emitting element ED-3 that emits blue light. For example, the red light-emitting region PXA-R, the green light-emitting region PXA-G, and the blue light-emitting region PXA-B of the display device DD may correspond to the first light-emitting element ED-1, the second light-emitting element ED-2, and the third light-emitting element ED-3, respectively.

[0203] However, the embodiment is not limited thereto, and the first to third light-emitting elements ED-1, ED-2, and ED-3 may emit light within the same wavelength range, or at least one light-emitting element may emit light within a wavelength range different from that of the remaining light-emitting elements. For example, the first to third light-emitting elements ED-1, ED-2, and ED-3 may each emit blue light.

[0204] The light-emitting regions PXA-R, PXA-G, and PXA-B in the display device DD according to an embodiment may be arranged in a stripe configuration. Referring to Figure 1 , the red light-emitting region PXA-R, the green light-emitting region PXA-G, and the blue light-emitting region PXA-B may be arranged along the second direction axis DR2, respectively. In another embodiment, the red light-emitting region PXA-R, the green light-emitting region PXA-G, and the blue light-emitting region PXA-B may be arranged in this repeating order along the first direction axis DR1.

[0205] Figure 1 and Figure 2 illustrate that the light-emitting regions PXA-R, PXA-G, and PXA-B all have the same area, but the embodiment is not limited thereto. In an embodiment, depending on the wavelength range of the emitted light, the sizes or shapes of the light-emitting regions PXA-R, PXA-G, and PXA-B may be different from each other. The areas of the light-emitting regions PXA-R, PXA-G, and PXA-B may be the areas in the plan view defined by the first direction axis DR1 and the second direction axis DR2. The third direction axis DR3 may be perpendicular to the plane defined by the first direction axis DR1 and the second direction axis DR2.

[0206] The arrangement of the light-emitting regions PXA-R, PXA-G, and PXA-B is not limited to the configuration illustrated in Figure 1 , and depending on the display quality characteristics required for the display device DD, the order of arranging the red light-emitting region PXA-R, the green light-emitting region PXA-G, and the blue light-emitting region PXA-B may be provided in various combinations. For example, the light-emitting regions PXA-R, PXA-G, and PXA-B may be arranged in a honeycomb configuration (such as ) or in a diamond configuration (such as Diamond ).

[0207] The areas of the light-emitting regions PXA-R, PXA-G, and PXA-B may be different from each other. For example, in an embodiment, the area of the green light-emitting region PXA-G may be smaller than the area of the blue light-emitting region PXA-B, but the embodiment is not limited thereto.

[0208] Hereinafter, Figures 3 to 6 are schematic cross-sectional views of a light-emitting element ED according to an embodiment. According to the embodiment shown in Figure 3 , the light-emitting element ED may include a first electrode EL1, a hole transport region HTR, an emission layer EML, an electron transport region ETR, and a second electrode EL2 stacked in this order. In the light-emitting element ED according to the embodiment, the emission layer EML may include a stacked first emission layer EML1 and second emission layer EML2.

[0209] Compared with Figure 3 is a schematic cross-sectional view of such a light-emitting element ED according to an embodiment, in which 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. Compared with Figure 4 Figure 3 is a schematic cross-sectional view of such a light-emitting element ED according to an embodiment, in which 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. Compared with Figure 5 Figure 4 is a schematic cross-sectional view of a light-emitting element ED according to an embodiment further including a capping layer CPL provided on the second electrode EL2. Figure 6

[0210] The first electrode EL1 has conductivity. The first electrode EL1 may be formed of a metal material, a metal alloy, or a conductive compound. The first electrode EL1 may be an anode or a cathode. However, the embodiment is not limited thereto. In the embodiment, the first electrode EL1 may be a pixel electrode. The first electrode EL1 may be a transmissive electrode, a transmissive-reflective electrode, or a reflective electrode. The first electrode EL1 may include at least one of Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF, Mo, Ti, W, In, Sn, and Zn, or may include an oxide, a compound, or a mixture thereof.

[0211] ​​​If the first electrode EL1 is a transmissive electrode, the first electrode EL1 may include a transparent metal oxide (e.g., indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), or indium tin zinc oxide (ITZO)). If the first electrode EL1 is a transmissive-reflective electrode or a reflective electrode, the first electrode EL1 may include Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF, Mo, Ti, W, their compounds, or their mixtures (e.g., a mixture of Ag and Mg), or a material having a multilayer structure, such as LiF / Ca (a stacked structure of LiF and Ca) or LiF / Al (a stacked structure of LiF and Al). In another embodiment, the first electrode EL1 may have a multilayer structure including a reflective film or a transmissive-reflective film formed of the above materials and a transparent conductive film formed of ITO, IZO, ZnO, ITZO, etc. For example, the first electrode EL1 may have a three-layer structure of ITO / Ag / ITO, but the embodiments are not limited thereto. In an embodiment, the first electrode EL1 may include the above metal materials, a combination of at least two of the above metal materials, or oxides of the above metal materials, etc. The thickness of the first electrode EL1 may be in the range of about to about . For example, the thickness of the first electrode EL1 may be in the range of about to about .

[0212] The hole transport region HTR may be provided on the first electrode EL1. The hole transport region HTR may include at least one of a hole injection layer HIL, a hole transport layer HTL, a buffer layer (not shown), an emission assist layer (not shown), and an electron blocking layer EBL. The thickness of the hole transport region HTR may be, for example, in the range of about to about .

[0213] The hole transport region HTR may have a single-layer structure composed of a single layer (composed of a single material), a single-layer structure composed of a single layer including different materials, or a multilayer structure including multiple layers containing different materials.

[0214] In an embodiment, the hole transport region HTR may have a single-layer structure of a hole injection layer HIL or a hole transport layer HTL, or may have a single-layer structure formed of a hole injection material and a hole transport material. In an embodiment, the hole transport region HTR may have a single-layer structure formed of different materials, or may have a structure in which a hole injection layer HIL / hole transport layer HTL, a hole injection layer HIL / hole transport layer HTL / buffer layer (not shown), a hole injection layer HIL / buffer layer (not shown), a hole transport layer HTL / buffer layer (not shown), or a hole injection layer HIL / hole transport layer HTL / electron blocking layer EBL are stacked from the first electrode EL1 in the order described for each, but the embodiments are not limited thereto.

[0215] The hole transport region HTR can be formed using various methods such as vacuum deposition, spin coating, casting, Langmuir-Blodgett (LB) method, inkjet printing, laser printing, and laser-induced thermal imaging (LITI) method.

[0216] In the light-emitting element ED according to an embodiment, the hole transport region HTR may include a compound represented by Formula H-1:

[0217] [Formula H-1]

[0218]

[0219] In Formula H-1, L1 and L2 may each independently be a direct bond, a substituted or unsubstituted arylene having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroarylene having 2 to 30 ring carbon atoms. In Formula H-1, a and b may each independently be an integer selected from 0 to 10. When a or b is 2 or greater, a plurality of L1 groups or a plurality of L2 groups may each independently be a substituted or unsubstituted arylene having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroarylene having 2 to 30 ring carbon atoms.

[0220] In Formula H-1, Ar1 and Ar2 may each independently be a substituted or unsubstituted aryl having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl having 2 to 30 ring carbon atoms. In Formula H-1, Ar3 may be a substituted or unsubstituted aryl having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl having 2 to 30 ring carbon atoms.

[0221] In an embodiment, the compound represented by Formula H-1 may be a monoamine compound. In another embodiment, the compound represented by Formula H-1 may be a diamine compound in which at least one of Ar1 to Ar3 includes an amino group as a substituent. In an embodiment, the compound represented by Formula H-1 may be a carbazole compound in which at least one of Ar1 and Ar2 includes a substituted or unsubstituted carbazolyl group, or may be a fluorene compound in which at least one of Ar1 and Ar2 includes a substituted or unsubstituted fluorenyl group.

[0222] The compound represented by Formula H-1 may be any compound selected from the compound group H. However, the compounds listed in the compound group H are only examples, and the compound represented by Formula H-1 is not limited to the compound group H:

[0223] [Compound Group H]

[0224]

[0225]

[0226] The hole transport region HTR may include phthalocyanine compounds (such as copper phthalocyanine), N 1 ,N 1 ’-([1,1’-Biphenyl]-4,4’-diyl)bis(N 1 -phenyl-N 4 ,N 4 -di-m-tolylbenzene-1,4-diamine) (DNTPD), 4,4’,4”-[Tris(3-methylphenyl)phenylamino]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’-di(naphthalen-1-yl)-N,N’-diphenyl-benzidine (NPB), a triphenylamine-containing polyether ketone (TPAPEK), 4-isopropyl-4’-methyldiphenyliodonium [tetrakis(pentafluorophenyl)borate], dipyrazino[2,3-f:2’,3’-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile (HAT-CN), etc.

[0227] The hole transport region HTR may include carbazole derivatives (e.g., N-phenylcarbazole or polyvinylcarbazole), fluorene derivatives, triphenylamine derivatives (e.g., N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1-biphenyl]-4,4'-diamine (TPD), 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) or 1,3-bis(N-carbazolyl)benzene (mCP)), etc.

[0228] In an embodiment, the hole transport region HTR may include 9-(4-tert-butylphenyl)-3,6-bis(triphenylsilyl)-9H-carbazole (CzSi), 9-phenyl-9H-3,9'-bicarbazole (CCP), 1,3-bis(1,8-dimethyl-9H-carbazol-9-yl)benzene (mDCP), etc.

[0229] The hole transport region HTR may include the above compounds of the hole transport region HTR in at least one of the hole injection layer HIL, the hole transport layer HTL, and the electron blocking layer EBL.

[0230] The thickness of the hole transport region HTR may be in the range of about to about . For example, the thickness of the hole transport region HTR may be in the range of about to about . When the hole transport region HTR includes the hole injection layer HIL, the hole injection layer HIL may have a thickness in the range of about to about . When the hole transport region HTR includes the hole transport layer HTL, the hole transport layer HTL may have a thickness in the range of about to about . When the hole transport region HTR includes the electron blocking layer EBL, the electron blocking layer EBL may have a thickness in the range of about to about . If the thickness of the hole transport region HTR, the thickness of the hole injection layer HIL, the thickness of the hole transport layer HTL, and the thickness of the electron blocking layer EBL satisfy the above ranges, satisfactory hole transport characteristics can be achieved without significantly increasing the driving voltage.

[0231] 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. The charge generation material may be, for example, a p-dopant. The p-dopant may include at least one of metal halides, quinone derivatives, metal oxides, and cyanide-containing compounds, but the embodiments are not limited thereto. For example, the p-dopant may include metal halides (such as CuI or RbI), quinone derivatives (such as tetracyanoquinodimethane (TCNQ) or 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ)), metal oxides (such as tungsten oxide or molybdenum oxide), cyanide-containing compounds (such as dipyrazino[2,3-f:2’,3’-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile (HAT-CN) or 4-[[2,3-bis[cyano-(4-cyano-2,3,5,6-tetrafluorophenyl)methylene]cyclopropyl]-cyanomethyl]-2,3,5,6-tetrafluorobenzonitrile (NDP9)), etc., but the embodiments are not limited thereto.

[0232] 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 buffer layer (not shown) and an electron blocking layer EBL. The buffer layer (not shown) may compensate for the resonance distance according to the wavelength of the light emitted from the emission layer EML, and thus may increase the light emission efficiency. The materials that may be included in the hole transport region HTR may be used as the materials in the buffer layer (not shown). The electron blocking layer EBL may prevent electrons from being injected from the electron transport region ETR into the hole transport region HTR.

[0233] The emission layer EML may be provided on the hole transport region HTR.

[0234] The emission layer EML may be formed by using various methods such as vacuum deposition, spin coating, casting, Langmuir-Blodgett (LB) method, inkjet printing, laser printing, and laser-induced thermal imaging (LITI) method.

[0235] The emission layer EML may have a structure including multiple layers. The emission layer EML may include a first emission layer EML1 and a second emission layer EML2. In the specification, the emission layer EML is shown as having a two-layer structure, but the embodiments are not limited thereto. In an embodiment, the emission layer EML may further include a single third emission layer (not shown) or multiple third emission layers (not shown) that may be provided on the lower part of the first emission layer EML1, on the upper part of the second emission layer EML2, or between the first emission layer EML1 and the second emission layer EML2.

[0236] The emission layer EML may have, for example, at about to about a thickness within the range of. The first emission layer EML1 may have a thickness within the range of about to about . For example, the first emission layer EML1 may have a thickness within the range of about to about . The second emission layer EML2 may have a thickness within the range of about to about . For example, the second emission layer EML2 may have a thickness within the range of about to about .

[0237] In an embodiment, the first emission layer EML1 may emit delayed fluorescence. For example, the first emission layer EML1 may emit delayed fluorescence by thermally activated delayed fluorescence (TADF).

[0238] The first emission layer EML1 may include the (1-1) compound. The (1-1) compound according to an embodiment may have a lowest excited triplet energy level (T1) within the range of about 2.5 eV to about 3.1 eV. For example, the (1-1) compound may have a lowest excited triplet energy level (T1) within the range of about 2.5 eV to about 2.8 eV. The first emission layer EML1 may include the (1-1) compound as a dopant. The (1-1) compound according to an embodiment may be a thermally activated delayed fluorescence dopant material in the first emission layer EML1.

[0239] The (1-1) compound according to an embodiment may include a structure in which a first aromatic ring to a third aromatic ring are fused via a boron atom, a first nitrogen atom, and a second nitrogen atom. The first aromatic ring to the third aromatic ring may each be connected to the boron atom, the first aromatic ring and the third aromatic ring may be connected to each other via the first nitrogen atom, and the second aromatic ring and the third aromatic ring may be connected to each other via the second nitrogen atom. In an embodiment, the first aromatic ring to the third aromatic ring may be 6-membered aromatic rings. For example, the first aromatic ring to the third aromatic ring may each be a benzene ring. In the specification, the five-membered ring fused structure formed by the boron atom, the first nitrogen atom, the second nitrogen atom, and the first aromatic ring to the third aromatic ring fused via the boron atom, the first nitrogen atom, and the second nitrogen atom may be referred to as the "first fused ring nucleus".

[0240] The (1-1) compound according to an embodiment may be represented by Formula 1:

[0241] [Formula 1]

[0242]

[0243] The (1-1) compound represented by Formula 1 may have a structure in which three aromatic rings are fused via a boron atom, a first nitrogen atom, and a second nitrogen atom.

[0244] In Formula 1, R1 to R 11 may each independently be a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a hydroxyl group, a substituted or unsubstituted oxy group, a substituted or unsubstituted thio group, a substituted or unsubstituted seleno group, a substituted or unsubstituted telluro group, a substituted or unsubstituted boron group, a substituted or unsubstituted silyl group, a substituted or unsubstituted amino 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 aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring carbon atoms, or bond to an adjacent group to form a ring. For example, R1, R3 to R5, R8, R9 and R 11 may each independently be a hydrogen atom or a deuterium atom; R2, R6 and R7 may each independently be a hydrogen atom, a deuterium atom, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted carbazolyl group; and R 10 may be a substituted or unsubstituted tert-butyl group, a substituted or unsubstituted phenyl group, or a substituted or unsubstituted dibenzofuranyl group.

[0245] For example, R2 and R4 may each independently be an oxy group, a thio group, a seleno group, a telluro group, or an amino group substituted with a phenyl group, etc.; R3 may be a substituted or unsubstituted boron group; and when R2, R3 and R4 are bonded to each other, Formula 1 may provide four additional fused ring nuclei connected to the first fused ring nucleus via the boron atom of R3 and two heteroatoms of R2 and R4.

[0246] In Formula 1, X1 to X6 may each independently be a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a hydroxyl group, a substituted or unsubstituted oxy group, a substituted or unsubstituted thio group, a substituted or unsubstituted silyl group, a substituted or unsubstituted amino 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 aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring carbon atoms, or bond to an adjacent group to form a ring. For example, X1 to X6 may each independently be a hydrogen atom, a deuterium atom, a substituted or unsubstituted tert-butyl group, or a substituted or unsubstituted phenyl group. For example, Formula 1 may include a plurality of X6 groups, one of the plurality of X6 groups may be an unsubstituted oxy group, the remainder of the plurality of X6 groups may include unsubstituted phenyl groups, and when two X6 groups are bonded to each other, the (1-1) compound represented by Formula 1 may include a biphenyldibenzofuran moiety.

[0247] In Formula 1, n1, n3, n4, and n6 may each independently be an integer selected from 0 to 5. If n1, n3, n4, and n6 are each 0, the (1-1) compound may not be substituted by X1, X3, X4, and X6, respectively. The case where n1, n3, n4, and n6 are each 5 and each of the five groups of X1, X3, X4, and X6 is a hydrogen atom may be the same as the case where n1, n3, n4, and n6 are each 0. If n1, n3, n4, and n6 are each 2 or greater, the multiple groups of each of X1, X3, X4, and X6 may all be the same, or at least one of them may be different from the rest.

[0248] In Formula 1, n2 and n5 may each independently be an integer selected from 0 to 3. If n2 and n5 are each 0, the (1-1) compound may not be substituted by X2 and X5, respectively. The case where n2 and n5 are each 3 and each of the three groups of X2 and X5 is a hydrogen atom may be the same as the case where n2 and n5 are each 0. If n2 and n5 are each 2 or greater, the multiple groups of each of X2 and X5 may all be the same, or at least one of them may be different from the rest.

[0249] In the specification, in Formula 1, the benzene ring including R1 to R4 as substituents may correspond to the aforementioned first aromatic ring, the benzene ring including R5 to R8 as substituents may correspond to the aforementioned second aromatic ring, and the benzene ring including R9 to R 11 as a substituent may correspond to the aforementioned third aromatic ring. The nitrogen atoms in Formula 1 may respectively correspond to the first nitrogen atom and the second nitrogen atom as described above.

[0250] In an embodiment, the (1-1) compound represented by Formula 1 may be represented by one of Formula 1-1 to Formula 1-3:

[0251] [Formula 1-1]

[0252]

[0253] [Formula 1-2]

[0254]

[0255] [Formula 1-3]

[0256]

[0257] Formula 1-1 and Formula 1-3 each represent the case where R2 and R7 in Formula 1 are further defined, and Formula 1-2 represents the case where R2 and R6 in Formula 1 are further defined.

[0258] In Formulas 1-1 to 1-3, Y1 to Y8, Z1, and Z2 may each independently be a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a hydroxyl group, a substituted or unsubstituted oxy group, a substituted or unsubstituted thio group, a substituted or unsubstituted seleno group, a substituted or unsubstituted telluro group, a substituted or unsubstituted germanium group, a substituted or unsubstituted boron group, a substituted or unsubstituted silyl group, a substituted or unsubstituted amino 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 aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring carbon atoms, or bonded to an adjacent group to form a ring. For example, Y1 to Y8, Z1, and Z2 may each independently be a hydrogen atom, a deuterium atom, a substituted or unsubstituted silyl group, a substituted or unsubstituted tert-butyl group, a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, or a substituted or unsubstituted carbazolyl group. For example, two Y1 groups may be bonded to each other to form a ring. As another example, one Y1 group may be an unsubstituted oxy group or an unsubstituted thio group, another Y1 group may be an unsubstituted phenyl group, and the two Y1 groups may be bonded to each other so that the (1-1) compound represented by Formula 1-1 may include a benzothienocarbazole moiety or a benzofurancarbazole moiety.

[0259] In Formulas 1-1 to 1-3, m1 to m8 may each independently be an integer selected from 0 to 4. If m1 to m8 are each 0, the (1-1) compound may not be substituted by Y1 to Y8, respectively. The case where m1 to m8 are each 4 and four groups in each of Y1 to Y8 are hydrogen atoms may be the same as the case where m1 to m8 are each 0. When m1 to m8 are each 2 or greater, the multiple groups in each of Y1 to Y8 may all be the same, or at least one of them may be different from the rest.

[0260] In Formulas 1-1 and 1-2, p1 and p2 may each independently be an integer selected from 0 to 5. If p1 and p2 are each 0, the (1-1) compound may not be substituted by Z1 and Z2, respectively. The case where p1 and p2 are each 5 and the five Z1 groups and the five Z2 groups are all hydrogen atoms may be the same as the case where p1 and p2 are each 0. If p1 and p2 are each 2 or greater, the multiple groups in each of Z1 and Z2 may all be the same, or at least one of them may be different from the rest.

[0261] In Formulas 1-1 to 1-3, R1, R3 to R 11 , X1 to X6, and n1 to n6 may be the same as defined in Formula 1.

[0262] In an embodiment, the (1-1) compound represented by Formula 1 may be represented by Formula 1-4:

[0263] [Formula 1-4]

[0264]

[0265] Formula 1-4 represents the case where R1 to R4 in Formula 1 are further defined. Formula 1-4 represents the case where the four rings are additionally fused to the first fused ring nucleus through the substituents represented by R2 to R4.

[0266] In Formula 1-4, Q1 and Q2 can each independently be O, S, Se, Te, or N(R 30 ).

[0267] In Formula 1-4, R 21 to R 30 can each independently be a hydrogen atom, a deuterium atom, a halogen atom, a cyano 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 aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring carbon atoms, or bonded to an adjacent group to form a ring. For example, R 21 , R 22 , R 25 , R 26 , R 29 and R 30 can each independently be a hydrogen atom or a deuterium atom; and R 23 , R 24 , R 27 and R 28 can each independently be a hydrogen atom, a deuterium atom, a substituted or unsubstituted phenyl group, or a substituted or unsubstituted carbazolyl group. For example, when Q1 is N(R 30 ), R 30 can be a substituted or unsubstituted phenyl group, and R 22 and R 30 can be bonded to each other, such that Formula 1-4 can have a structure including an additional ring fused to the four fused rings formed by R2 and R3.

[0268] In Formula 1-4, R5 to R 11 , X1 to X6, and n1 to n6 can be the same as those defined in Formula 1.

[0269] In an embodiment, the (1-1) compound represented by Formula 1 can be represented by one of Formulas 1-5 to 1-11:

[0270] [Formula 1-5]

[0271]

[0272] [Formula 1-6]

[0273]

[0274] [Formula 1-7]

[0275]

[0276] [Formula 1-8]

[0277]

[0278] [Formula 1-9]

[0279]

[0280] [Formula 1-10]

[0281]

[0282] [Formula 1-11]

[0283]

[0284] Each of Formula 1-5 to Formula 1-11 represents a case where X1 to X6 in Formula 1 are further defined.

[0285] In Formula 1-5 to Formula 1-11, R1 to R 11 may be the same as those defined in Formula 1.

[0286] In an embodiment, in Formula 1, R 10 may be a group represented by one of Formula 3-1 to Formula 3-6: [Formula 3-1]

[0287]

[0288] [Formula 3-2]

[0289]

[0290] [Formula 3-3]

[0291]

[0292] [Formula 3-4]

[0293]

[0294] [Formula 3-5]

[0295]

[0296] [Formula 3-6]

[0297]

[0298] In Formulae 3-1 to 3-6, *— represents a bond with Formula 1.

[0299] In Formula 3-2, D represents a deuterium atom.

[0300] In an embodiment, the (1-1) compound represented by Formula 1 may be any compound selected from Compound Group 1-1. In an embodiment, in the light-emitting element ED, the first emission layer EML1 may include at least one (1-1) compound selected from Compound Group 1-1:

[0301] [Compound Group 1-1]

[0302]

[0303]

[0304]

[0305]

[0306] In Compound Group 1-1, D represents a deuterium atom.

[0307] The first emission layer EML1 according to the embodiment may include the (1-1) compound represented by Formula 1, thereby improving the light-emitting characteristics.

[0308] The (1-1) compound represented by Formula 1 includes a first fused ring nucleus in which the first aromatic ring to the third aromatic ring are fused by a boron atom, a first nitrogen atom, and a second nitrogen atom, and the (1-1) compound includes a terphenyl substituent attached to each of the first nitrogen atom and the second nitrogen atom. Accordingly, in the (1-1) compound according to the embodiment, the empty p-orbital of the boron atom can be protected by a steric effect, and the trigonal planar structure of the boron atom can be effectively maintained. Accordingly, the (1-1) compound according to the embodiment may have improved material stability, thereby preventing material deterioration. Since the (1-1) compound inhibits intermolecular interactions, the occurrence of phenomena such as aggregation, intermolecular excimer formation, or intermolecular exciplex formation can be reduced, and thus the light-emitting efficiency of the light-emitting element ED including the (1-1) compound can be increased.

[0309] The emission spectrum of the (1-1) compound represented by Formula 1 may have a FWQM (Full Width at Quarter Maximum) in the range of about 10 nm to about 50 nm. For example, the emission spectrum of the (1-1) compound represented by Formula 1 may have a FWQM in the range of about 20 nm to about 40 nm. When the FWQM of the emission spectrum of the (1-1) compound represented by Formula 1 is within any of the above ranges, applying the (1-1) compound to the light-emitting element ED can improve the luminous efficiency.

[0310] The (1-1) compound according to an embodiment may be included in the first emission layer EML1. The first emission layer EML1 may include a first light-emitting host and a first light-emitting dopant doped into the first light-emitting host. The first light-emitting dopant may include the (1-1) compound. The first emission layer EML1 according to an embodiment may emit delayed fluorescence by thermally activated delayed fluorescence, and the (1-1) compound included in the first emission layer EML1 may be used as a thermally activated delayed fluorescence dopant. For example, in the light-emitting element ED, the first emission layer EML1 may include at least one (1-1) compound selected from the group of compounds 1 as described above as a thermally activated delayed fluorescence dopant.

[0311] The (1-1) compound represented by Formula 1 may be a light-emitting material having a central wavelength in the range of about 430 nm to about 490 nm. For example, the (1-1) compound represented by Formula 1 may be a blue thermally activated delayed fluorescence dopant. However, the embodiment is not limited thereto, and the (1-1) compound may be used as a dopant material that emits light in various wavelength regions, such as a red emission dopant or a green emission dopant.

[0312] The first emission layer EML1 of the light-emitting element ED may emit blue light. For example, the first emission layer EML1 of the light-emitting element ED may emit blue light having a wavelength equal to or less than about 490 nm. However, the embodiment is not limited thereto, and the first emission layer EML1 may emit green light or red light.

[0313] In an embodiment, the first emission layer EML1 may include a variety of compounds. The first emission layer EML1 may include a (1-1) compound represented by Formula 1, and may further include at least one of a (1-2) compound represented by Formula HT-1, a (1-3) compound represented by Formula ET-1, and a (1-4) compound represented by Formula D-1. For example, the first emission layer EML1 may include a (1-1) compound represented by Formula 1, a (1-2) compound represented by Formula HT-1, a (1-3) compound represented by Formula ET-1, and a (1-4) compound represented by Formula D-1. In an embodiment, the first emission layer EML1 may be composed of: a (1-1) compound represented by Formula 1, a (1-2) compound represented by Formula HT-1, a (1-3) compound represented by Formula ET-1, and a (1-4) compound represented by Formula D-1.

[0314] In an embodiment, the first emission layer EML1 may include a (1-2) compound represented by Formula HT-1. In an embodiment, the first emission layer EML1 may include a first light-emitting host, and the first light-emitting host may include the (1-2) compound. In an embodiment, the (1-2) compound may be used as a hole-transporting host material in the first emission layer EML1.

[0315] [Formula HT-1]

[0316]

[0317] In Formula HT-1, A1 to A8 may each independently be N or C(R 51 ). For example, A1 to A8 may each independently be C(R 51 ). As another example, one of A1 to A8 may be N, and the remainder of A1 to A8 may each independently be C(R 51 ).

[0318] In Formula HT-1, L1 may be a direct bond, a substituted or unsubstituted arylene having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroarylene having 2 to 30 ring carbon atoms. For example, L1 may be a direct bond, a substituted or unsubstituted phenylene, a substituted or unsubstituted divalent biphenyl, or a substituted or unsubstituted divalent carbazolyl, etc., but the embodiments are not limited thereto.

[0319] In Formula HT-1, Y a may be a direct bond, C(R 52 )(R 53 ), or Si(R 54 )(R 55 ). For example, the two benzene rings connected to the nitrogen atom in Formula HT-1 may be directly bonded, are connected to each other. In Formula HT-1, when Y a is a direct bond, the (1-2) compound represented by Formula HT-1 may include a carbazole moiety.

[0320] In Formula HT-1, Ar1 may be a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms or a substituted or unsubstituted heteroaryl group having 2 to 30 ring carbon atoms. For example, Ar1 may be a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted dibenzofuranyl group, a substituted or unsubstituted dibenzothiophenyl group, a substituted or unsubstituted biphenyl group, etc., but the embodiments are not limited thereto.

[0321] In Formula HT-1, R 51 to R 55 may each independently be a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a substituted or unsubstituted silyl group, a substituted or unsubstituted thio group, a substituted or unsubstituted oxy group, a substituted or unsubstituted amino group, a substituted or unsubstituted boron 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 aryl group having 6 to 60 ring carbon atoms or a substituted or unsubstituted heteroaryl group having 2 to 60 ring carbon atoms, or bonded to an adjacent group to form a ring. For example, R 51 to R 55 may each independently be a hydrogen atom or a deuterium atom. For example, R 51 to R 55 may each independently be an unsubstituted methyl group or an unsubstituted phenyl group.

[0322] In an embodiment, the (1-2) compound represented by Formula HT-1 may be selected from Compound Group 1-2. In an embodiment, in the light-emitting element ED, the (1-2) compound may include at least one compound selected from Compound Group 1-2:

[0323] [Compound Group 1-2]

[0324]

[0325]

[0326] In Compound Group 1-2, D represents a deuterium atom, and Ph represents a substituted or unsubstituted phenyl group. For example, in Compound Group 1-2, Ph may represent an unsubstituted phenyl group.

[0327] In an embodiment, the first emission layer EML1 may further include a compound of formula (1-3) represented by formula ET-1. In an embodiment, the first emission layer EML1 may include a first light-emitting host, and the first light-emitting host may include the compound of formula (1-3). In an embodiment, the compound of formula (1-3) may be used as an electron transport host material in the first emission layer EML1.

[0328] [Formula ET-1]

[0329]

[0330] In formula ET-1, at least one of X1 to X3 may each be N, and the remainder of X1 to X3 may each independently be C(R 56 ). For example, one of X1 to X3 may be N, and the remainder of X1 to X3 may each independently be C(R 56 ). Accordingly, the compound of formula (1-3) represented by formula ET-1 may include a pyridine moiety. As yet another example, two of X1 to X3 may each be N, and the remainder of X1 to X3 may be C(R 56 ). Accordingly, the compound of formula (1-3) represented by formula ET-1 may include a pyrimidine moiety. As yet another example, X1 to X3 may each be N. Accordingly, the compound of formula (1-3) represented by formula ET-1 may include a triazine moiety.

[0331] In formula ET-1, R 56 may be a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 60 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 60 ring carbon atoms.

[0332] In formula ET-1, b1 to b3 may each independently be an integer selected from 0 to 10.

[0333] In formula ET-1, Ar2 to Ar4 may each independently be a hydrogen atom, a deuterium atom, 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 2 to 30 ring carbon atoms. For example, Ar2 to Ar4 may each independently be a substituted or unsubstituted phenyl group or a substituted or unsubstituted carbazolyl group.

[0334] In Formula ET-1, L2 to L4 may each independently be a direct bond, a substituted or unsubstituted arylene having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroarylene having 2 to 30 ring carbon atoms. When b1 to b3 are each 2 or greater, the multiple groups of each of L2 to L4 may each independently be a substituted or unsubstituted arylene having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroarylene having 2 to 30 ring carbon atoms.

[0335] In an embodiment, the (1-3) compound represented by Formula ET-1 may be selected from Compound Group 1-3. In an embodiment, in the light-emitting element ED, the (1-3) compound may include at least one compound selected from Compound Group 1-3:

[0336] [Compound Group 1-3]

[0337]

[0338]

[0339]

[0340] In Compound Group 1-3, D represents a deuterium atom, and Ph represents an unsubstituted phenyl group.

[0341] In an embodiment, the first emission layer EML1 may include the (1-2) compound and the (1-3) compound, and the (1-2) compound and the (1-3) compound may form an exciplex. In the first emission layer EML1, an exciplex may be formed by the (1-2) compound as a hole-transporting host and the (1-3) compound as an electron-transporting host. The lowest excited triplet energy level of the exciplex formed by the hole-transporting host and the electron-transporting host may correspond to the difference between the lowest unoccupied molecular orbital (LUMO) energy level of the electron-transporting host and the highest occupied molecular orbital (HOMO) energy level of the hole-transporting host.

[0342] For example, the absolute value of the lowest excited triplet energy level (T1) of the exciplex formed by the hole-transporting host and the electron-transporting host may be in the range of about 2.4 eV to about 3.0 eV. The lowest excited triplet energy level of the exciplex may be a value less than the energy gap of each host material. The exciplex may have a lowest excited triplet energy level equal to or less than about 3.0 eV, which is the energy gap between the hole-transporting host and the electron-transporting host.

[0343] In an embodiment, in addition to the (1-1) compound, the (1-2) compound, and the (1-3) compound as described above, the first emission layer EML1 may further include a (1-4) compound. The (1-4) compound can be used as a sensitizer in the first emission layer EML1. The first emission layer EML1 can emit light by transferring energy from the (1-4) compound to the (1-1) compound.

[0344] In an embodiment, the first emission layer EML1 may further include an organometallic complex as the (1-4) compound, and the organometallic complex includes platinum (Pt) as the central metal atom and ligands connected to the central metal atom. In an embodiment, the first emission layer EML1 may further include a (1-4) compound represented by Formula D-1:

[0345] [Formula D-1]

[0346]

[0347] In Formula D-1, Q1 to Q4 may each independently be C or N.

[0348] In Formula D-1, C1 to C4 may each independently be a substituted or unsubstituted hydrocarbon ring group having 5 to 30 ring carbon atoms or a substituted or unsubstituted heterocyclic group having 2 to 30 ring carbon atoms.

[0349] In Formula D-1, L 11 to L 13 may each independently be a direct bond, *—O—*, *—S—*, a substituted or unsubstituted alkylene 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. In L 11 to L 13 , ——* represents a bond to one of C1 to C4.

[0350] In Formula D-1, c1 to c3 may each independently be 0 or 1. If c1 is 0, C1 and C2 may not be directly connected to each other. If c2 is 0, C2 and C3 may not be directly connected to each other. If c3 is 0, C3 and C4 may not be directly connected to each other.

[0351] In Formula D-1, R 61 to R 66Each may independently be a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a substituted or unsubstituted silyl group, a substituted or unsubstituted thio group, a substituted or unsubstituted oxy group, a substituted or unsubstituted amino group, a substituted or unsubstituted boron 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 aryl group having 6 to 60 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 60 ring carbon atoms, or bonded to an adjacent group to form a ring. For example, R 61 to R 66 may each independently be a substituted or unsubstituted methyl group or a substituted or unsubstituted tert-butyl group.

[0352] In formula D-1, d1 to d4 may each independently be an integer selected from 0 to 4. If d1 to d4 are each 0, the (1-4) compounds may not be substituted by R 61 to R 64 respectively. Among them, the case where d1 to d4 are each 4 and all four groups of each of R 61 to R 64 are hydrogen atoms may be the same as the case where d1 to d4 are each 0. When d1 to d4 are each 2 or more, the multiple groups of each of R 61 to R 64 may all be the same, or at least one of them may be different from the rest.

[0353] In an embodiment, in formula D-1, C1 to C4 may each independently be a substituted or unsubstituted hydrocarbon ring group or a substituted or unsubstituted heterocyclic group represented by one of formula C-1 to formula C-4:

[0354]

[0355] In formula C-1 to formula C-4, P1 may be C——* or C(R 74 ), P2 may be N——* or N(R 81 ), P3 may be N——* or N(R 82 ), and P4 may be C——* or C(R 88 ).

[0356] In formula C-1 to formula C-4, R 71 to R 88 may 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 2 to 30 ring carbon atoms, or bonded to an adjacent group to form a ring.

[0357] In formula C-1 to formula C-4, represents the bond with Pt as the central metal atom, and —* represents the bond with the adjacent cyclic groups C1 to C4 or the linking moiety L 11 to L 13 bond.

[0358] In an embodiment, the first emission layer EML1 may include the (1-1) compound represented by Formula 1, and at least one of the (1-2) compound, the (1-3) compound, and the (1-4) compound. In an embodiment, the emission layer EML may include the (1-1) compound, the (1-2) compound, and the (1-3) compound. In the emission layer EML, the (1-2) compound and the (1-3) compound may form an exciplex, and energy may be transferred from the exciplex to the (1-1) compound, thereby emitting light.

[0359] In another embodiment, the emission layer EML may include the (1-1) compound, the (1-2) compound, the (1-3) compound, and the (1-4) compound. In the emission layer EML, the (1-2) compound and the (1-3) compound may form an exciplex, and energy may be transferred from the exciplex to the (1-4) compound and the (1-1) compound, thereby emitting light. In an embodiment, the (1-4) compound may be a sensitizer. In the light-emitting device ED, the (1-4) compound included in the emission layer EML may be used as a sensitizer that transfers energy from the first light-emitting host (e.g., exciplex host) to the (1-1) compound as the first light-emitting dopant. The (1-4) compound used as an auxiliary dopant may accelerate the energy transfer to the (1-1) compound used as the first light-emitting dopant, thereby increasing the emission ratio of the (1-1) compound. Therefore, the first emission layer EML1 may exhibit improved light-emitting efficiency. When the energy transferred to the (1-1) compound increases, the excitons formed in the first emission layer EML1 may not accumulate and may emit light quickly, so that the deterioration of the light-emitting device ED can be reduced. Accordingly, the service life of the light-emitting device ED can be increased.

[0360] The light-emitting device ED may include the (1-1) compound, the (1-2) compound, the (1-3) compound, and the (1-4) compound, and the first emission layer EML1 may include a combination of two host materials and two dopant materials. In the light-emitting device ED, the first emission layer EML1 may include the (1-2) compound and the (1-3) compound as two different hosts, the (1-1) compound that emits delayed fluorescence, and the (1-4) compound as an organometallic complex, so that the light-emitting device ED can exhibit excellent light-emitting efficiency characteristics.

[0361] In an embodiment, the (1-4) compound represented by Formula D-1 may be selected from Compound Group 1-4. In an embodiment, in the light-emitting element ED, the (1-4) compound may include at least one compound selected from Compound Group 1-4:

[0362] [Compound Group 1-4]

[0363]

[0364]

[0365] In Compound Group 1-4, D represents a deuterium atom.

[0366] In the light-emitting element ED, when the first emission layer EML1 includes the (1-1) compound, the (1-2) compound, the (1-3) compound, and the (1-4) compound, the amount of the (1-1) compound may be in the range of about 0.1 wt% to about 5 wt% relative to the total weight of the (1-1) compound, the (1-2) compound, the (1-3) compound, and the (1-4) compound. However, the embodiment is not limited thereto. When the amount of the (1-1) compound satisfies the above range, the energy transferred from the (1-2) compound and the (1-3) compound to the (1-1) compound can be increased, and thus the luminous efficiency and the element service life can be increased.

[0367] In the first emission layer EML1, the total amount of the (1-2) compound and the (1-3) compound may be in the range of about 65 wt% to about 95 wt% relative to the total weight of the (1-1) compound, the (1-2) compound, the (1-3) compound, and the (1-4) compound.

[0368] In the total amount of the (1-2) compound and the (1-3) compound in the first emission layer EML1, the weight ratio of the (1-2) compound to the (1-3) compound may be in the range of about 3:7 to about 7:3.

[0369] When the amounts of the (1-2) compound and the (1-3) compound satisfy the above range and ratio, the charge balance characteristics in the first emission layer EML1 can be improved, and thus the luminous efficiency and the element service life can be increased. When the amounts of the (1-2) compound and the (1-3) compound deviate from the above range and ratio, charge balance in the first emission layer EML1 may not be achieved, thereby reducing the luminous efficiency and the light-emitting element ED may be easily deteriorated.

[0370] Relative to the total weight of the (1-1) compound, the (1-2) compound, the (1-3) compound, and the (1-4) compound, the amount of the (1-4) compound in the first emission layer EML1 can be in the range of about 10 wt% to about 30 wt%. However, the embodiments are not limited thereto. When the amount of the (1-4) compound satisfies the above range, the energy transferred from the host (e.g., exciplex host) to the (1-1) compound as a luminescent dopant can be increased, so that the emission ratio can be improved. Accordingly, the luminous efficiency of the first emission layer EML1 can be improved. When the amounts of the (1-1) compound, the (1-2) compound, the (1-3) compound, and the (1-4) compound included in the first emission layer EML1 satisfy the above range and ratio, excellent luminous efficiency and long service life can be achieved.

[0371] In an embodiment, the second emission layer EML2 can emit delayed fluorescence. For example, the second emission layer EML2 can emit fluorescence through triplet-triplet annihilation (TTA). The second emission layer EML2 can emit fluorescence through a phenomenon in which singlet excitons are generated by the collision of triplet excitons.

[0372] The second emission layer EML2 can include the (2-1) compound. The (2-1) compound according to an embodiment can have a lowest excited triplet energy level (T1) in the range of about 1.5 eV to about 2.1 eV. The second emission layer EML2 can include the (2-1) compound as a dopant. The (2-1) compound according to an embodiment can be a dopant material that emits fluorescence through triplet-triplet annihilation (TTA) in the second emission layer EML2.

[0373] The (2-1) compound according to an embodiment can include a structure in which a first aromatic ring, a second aromatic ring, and a first heterocycle are fused via a boron atom, a first nitrogen atom, and a second nitrogen atom. The first aromatic ring, the second aromatic ring, and the first heterocycle can each be connected to the boron atom, the first aromatic ring and the second aromatic ring can be connected to each other via the first nitrogen atom, and the first heterocycle and the second aromatic ring can be connected to each other via the second nitrogen atom. In an embodiment, the first aromatic ring and the second aromatic ring can be 6-membered aromatic rings. For example, the first aromatic ring and the second aromatic ring can each be a benzene ring. In an embodiment, the first heterocycle can be a structure in which a 5-membered ring including a first heteroatom and a 6-membered aromatic ring are fused. For example, the first heterocycle can be benzofuranyl, benzothiophenyl, benzoselenophenyl, or benzotellurophenyl. In the specification, the six-ring fused structure formed by the boron atom, the first nitrogen atom, the second nitrogen atom, and the first aromatic ring, the second aromatic ring, and the first heterocycle fused via the boron atom, the first nitrogen atom, and the second nitrogen atom can be referred to as the "second fused ring core".

[0374] The (2-1) compound according to an embodiment can be represented by Formula 2:

[0375] [Formula 2]

[0376]

[0377] The (2-1) compound represented by Formula 2 may have a structure in which two aromatic rings and one heterocyclic ring are fused via a boron atom, a first nitrogen atom, and a second nitrogen atom.

[0378] In Formula 2, X may be O, S, Se, or Te.

[0379] In Formula 2, Ar may be a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms or a substituted or unsubstituted heteroaryl group having 2 to 30 ring carbon atoms. For example, Ar may be a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted terphenyl group, a substituted or unsubstituted anthryl group, a substituted or unsubstituted pyrenyl group, a substituted or unsubstituted acenaphthylenyl group, or a substituted or unsubstituted acridinyl group.

[0380] In Formula 2, R 12 to R 17 and R x1 to R x3 may each independently be a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a hydroxyl group, a substituted or unsubstituted silyl 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 2 to 30 ring carbon atoms. For example, R 12 to R 14 , R 15 and R 17 may each independently be a hydrogen atom or a deuterium atom; R 16 may be a substituted or unsubstituted tert-butyl group, a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted anthryl group, a substituted or unsubstituted pyrenyl group, a substituted or unsubstituted acenaphthylenyl group, or a substituted or unsubstituted acridinyl group; and R x1 to R x3 may each independently be a hydrogen atom, a deuterium atom, or an unsubstituted tert-butyl group.

[0381] In Formula 2, R y1 , R y2 and R z1Each may independently be a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a hydroxyl group, a substituted or unsubstituted amino 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 aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, or bonded to an adjacent group to form a ring. For example, R y1 、R y2 and R z1 may each independently be a hydrogen atom, a deuterium atom, a substituted or unsubstituted amino group, a substituted or unsubstituted tert-butyl group, a substituted or unsubstituted anthryl group, a substituted or unsubstituted pyrenyl group, a substituted or unsubstituted acenaphthylenyl group, or a substituted or unsubstituted acridinyl group.

[0382] For example, two R y1 groups may be bonded to each other to form a ring. Two R y1 groups may each independently be a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, and when the two R y1 groups are bonded to each other, the (2-1) compound represented by Formula 2 may include a pyrene moiety together with a benzocyclic ring substituted by R y1 .

[0383] In Formula 2, x1 and x3 may each independently be an integer selected from 0 to 5. If x1 and x3 are each 0, the (2-1) compound may not be substituted by R x1 and R x3 respectively. When x1 and x3 are each 5 and the five R x1 groups and the five R x3 groups are all hydrogen atoms, the case may be the same as the case where x1 and x3 are each 0. If x1 and x3 are each 2 or more, the multiple groups of each of R x1 and R x3 may all be the same, or at least one of them may be different from the rest.

[0384] In Formula 2, x2 may be an integer selected from 0 to 3. If x2 is 0, the (2-1) compound may not be substituted by R x2 . When x2 is 3 and the three R x2 groups are all hydrogen atoms, the case may be the same as the case where x2 is 0. If x2 is 2 or more, the multiple R x2 groups may all be the same, or at least one R x2 group may be different from the rest.

[0385] In Formula 2, y1, y2, and z1 may each independently be an integer selected from 0 to 4. If y1, y2, and z1 are each 0, the (2-1) compound may not be substituted by R y1 , R y2 , and R z1 respectively. When y1, y2, and z1 are each 4 and all four groups of each of R y1 , R y2 , and R z1 are hydrogen atoms, it may be the same as the case where y1, y2, and z1 are each 0. If y1, y2, and z1 are each 2 or greater, the multiple groups of each of R y1 , R y2 , and R z1 may all be the same, or at least one of them may be different from the rest.

[0386] In the specification, in Formula 2, the benzene ring including R 12 to R 14 as substituents may correspond to the aforementioned first aromatic ring, the benzene ring including R 15 to R 17 as substituents may correspond to the aforementioned second aromatic ring, and the heterocyclic ring including R z1 as a substituent and containing X as a ring-forming atom may correspond to the aforementioned first heterocyclic ring. The nitrogen atoms that are ring-forming atoms together with boron in Formula 2 may respectively correspond to the first nitrogen atom and the second nitrogen atom, and X may correspond to the first heteroatom.

[0387] In an embodiment, in Formula 2, at least one of R 16 , R y1 , R y2 , R z1 , and Ar may each independently be a group represented by one of Formula 4-1 to Formula 4-4:

[0388] [Formula 4-1]

[0389]

[0390] [Formula 4-2]

[0391]

[0392] [Formula 4-3]

[0393]

[0394] [Formula 4-4]

[0395]

[0396] In Formulas 4-1 to 4-4, L1 to L4 may each independently be a direct bond or a substituted or unsubstituted arylene having 6 to 30 ring carbon atoms. In an embodiment, in Formulas 4-1 to 4-4, L1 to L4 may each independently be a direct bond, a substituted or unsubstituted phenylene, or a substituted or unsubstituted biphenylene.

[0397] In Formulas 4-1 to 4-4, R a1 to R a4 may each independently be a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl having 1 to 20 carbon atoms, a substituted or unsubstituted aryl having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl having 2 to 30 ring carbon atoms, or may bond to an adjacent group to form a ring. In an embodiment, in Formulas 4-1 to 4-4, R a1 to R a4 may each independently be a hydrogen atom or a substituted or unsubstituted phenyl.

[0398] In Formulas 4-1 and 4-2, a1 and a2 may each independently be an integer selected from 0 to 9. If a1 and a2 are each 0, the (2-1) compound may not be substituted by R a1 and R a2 . Wherein a1 and a2 are each 9 and the nine R a1 groups and the nine R a2 groups are all hydrogen atoms, the case may be the same as the case where a1 and a2 are each 0. If a1 and a2 are each 2 or greater, the multiple groups of each of R a1 and R a2 may all be the same, or at least one thereof may be different from the remainder.

[0399] In Formula 4-3, a3 may be an integer selected from 0 to 7. If a3 is 0, the (2-1) compound may not be substituted by R a3 . Wherein a3 is 7 and the seven R a3 groups are all hydrogen atoms, the case may be the same as the case where a3 is 0. If a3 is 2 or greater, the multiple R a3 groups may all be the same, or at least one R a3 group may be different from the remainder.

[0400] In Formula 4-4, a4 may be an integer selected from 0 to 8. If a4 is 0, the (2-1) compound may not be substituted by R a4 . Wherein a4 is 8 and the eight R a4 groups are all hydrogen atoms, the case may be the same as the case where a4 is 0. If a4 is 2 or greater, the multiple R a4 groups may all be the same, or at least one R a4The group may be different from the remainder.

[0401] In Formulas 4-1 to 4-4, *— represents a bond with Formula 2.

[0402] In an embodiment, the (2-1) compound represented by Formula 2 may be represented by Formula 2-1:

[0403] [Formula 2-1]

[0404]

[0405] Formula 2-1 represents a case where Ar in Formula 2 is further defined.

[0406] In Formula 2-1, R b1 may be a hydrogen atom, a deuterium atom, 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 aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring carbon atoms. For example, R b1 may be a hydrogen atom, a deuterium atom, a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted anthracenyl group, a substituted or unsubstituted pyrenyl group, a substituted or unsubstituted acenaphthylenyl group, or a substituted or unsubstituted acridinyl group.

[0407] In Formula 2-1, R y1 , R y2 , R z1 and R b1 at least one of which may each independently be a group represented by one of Formulas 4-1 to 4-4. For example, R y1 , R y2 , R z1 and R b1 one of which may be a group represented by one of Formulas 4-1 to 4-4.

[0408] In Formula 2-1, b1 may be an integer selected from 0 to 5. If b1 is 0, the (2-1) compound may not be substituted by R b1 . Where b1 is 5 and all five R b1 groups are hydrogen atoms, it may be the same as the case where b1 is 0. If b1 is 2 or greater, the multiple R b1 groups may all be the same, or at least one R b1 group may be different from the remainder.

[0409] In Formula 2-1, X, R 12 to R 17 , R x1 to R x3 , R y1 , Ry2 , R z1 , x1 to x3, y1, y2, and z1 may be the same as defined in Formula 2.

[0410] In an embodiment, the (2-1) compound represented by Formula 2 may be represented by one of Formulas 2-2 to 2-4:

[0411] [Formula 2-2]

[0412]

[0413] [Formula 2-3]

[0414]

[0415] [Formula 2-4]

[0416]

[0417] Formulas 2-2 to 2-4 each represent a case where R in Formula 2 is further defined 16 .

[0418] In Formulas 2-2 to 2-4, R b2 to R b8 may each independently be a hydrogen atom, a deuterium atom, 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 aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring carbon atoms. For example, R b2 to R b8 may each independently be a hydrogen atom, a deuterium atom, a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted anthracenyl group, a substituted or unsubstituted pyrenyl group, a substituted or unsubstituted acenaphthylenyl group, or a substituted or unsubstituted acridinyl group.

[0419] In Formula 2-2, b2 may be an integer selected from 0 to 5. If b2 is 0, the (2-1) compound may not be substituted by R b2 . The case where b2 is 5 and all five R b2 groups are hydrogen atoms may be the same as the case where b2 is 0. If b2 is 2 or greater, the multiple R b2 groups may all be the same, or at least one R b2 group may be different from the rest.

[0420] In Formula 2-2, R y1 , R y2 , R z1 and R b2At least one of them may each independently be a group represented by one of Formula 4-1 to Formula 4-4. For example, R y1 , R y2 , R z1 , and R b2 may each independently be a group represented by one of Formula 4-1 to Formula 4-4.

[0421] In Formula 2-3, at least one of R y1 , R y2 , R z1 , R b3 , R b4 , and R b5 may each independently be a group represented by one of Formula 4-1 to Formula 4-4. For example, R y1 , R y2 , R z1 , R b3 , R b4 , and R b5 may each independently be a group represented by one of Formula 4-1 to Formula 4-4.

[0422] In Formula 2-4, at least one of R y1 , R y2 , R z1 , R b6 , R b7 , and R b8 may each independently be a group represented by one of Formula 4-1 to Formula 4-4. For example, R y1 , R y2 , R z1 , R b6 , R b7 , and R b8 may each independently be a group represented by one of Formula 4-1 to Formula 4-4.

[0423] In Formulas 2-2 to 2-4, X, Ar, R 12 to R 15 , R 17 , R x1 to R x3 , R y1 , R y2 , R z1 , x1 to x3, y1, y2, and z1 may be the same as those defined in Formula 2.

[0424] In an embodiment, the (2-1) compound represented by Formula 2 may be represented by Formula 2-5:

[0425] [Formula 2-5]

[0426]

[0427] Formula 2-5 represents the case where R in Formula 2 is further defined z1 and z1 is 1.

[0428] In Formula 2-5, R b9 and R b10 can each independently be a hydrogen atom, a deuterium atom, 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 aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, or bonded to an adjacent group to form a ring. For example, R b9 and R b10 can each independently be a hydrogen atom, a deuterium atom, a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted anthracenyl group, a substituted or unsubstituted pyrenyl group, a substituted or unsubstituted acenaphthylenyl group, or a substituted or unsubstituted acridinyl group. For example, when R b9 and R b10 are each an unsubstituted phenyl group, and R b9 and R b10 can be bonded to each other to form a ring with the nitrogen atom to which they are connected in Formula 2-5, the (2-1) compound represented by Formula 2-5 can include another carbazolyl group bonded to the second fused ring nucleus.

[0429] In Formula 2-5, at least one of R y1 , R y2 , R b9 and R b10 can each independently be a group represented by one of Formulas 4-1 to 4-4. For example, one of R y1 , R y2 , R b9 and R b10 can be a group represented by one of Formulas 4-1 to 4-4.

[0430] In Formula 2-5, X, Ar, R 12 to R 17 , R x1 to R x3 , R y1 , R y2 , x1 to x3, y1 and y2 can be the same as those defined in Formula 2.

[0431] In an embodiment, the (2-1) compound represented by Formula 2 can be represented by one of Formulas 2-6 to 2-8:

[0432] [Formula 2-6]

[0433]

[0434] [Formula 2-7]

[0435]

[0436] [Formula 2-8]

[0437]

[0438] Formula 2-6 represents the case where R in Formula 2 is further defined. z1 The cases where Formula 2-7 and Formula 2-8 each represent the case where R in Formula 2 is further defined. y2

[0439] In Formulas 2-6 to 2-8, X, Ar, R 12 to R 17 , R x1 to R x3 , R y1 , R y2 , R z1 , x1 to x3, y1, y2, and z1 may be the same as those defined in Formula 2.

[0440] In an embodiment, the (2-1) compound represented by Formula 2 may be any compound selected from Compound Group 2-1. In an embodiment, in the light-emitting element ED, the second emission layer EML2 may include at least one (2-1) compound selected from Compound Group 2-1:

[0441] [Compound Group 2-1]

[0442]

[0443]

[0444]

[0445]

[0446] In Compound Group 2-1, D represents a deuterium atom.

[0447] According to an embodiment, the second emission layer EML2 may include the (2-1) compound represented by Formula 2, thereby improving the light-emitting characteristics and achieving a long service life.

[0448] ​The (2-1) compound represented by Formula 2 includes a second fused ring nucleus in which the first aromatic ring and the second aromatic ring are fused to the first heterocycle via a boron atom, a first nitrogen atom, and a second nitrogen atom, and the (2-1) compound includes a carbazole substituent connected to the first aromatic ring and a terphenyl substituent connected to the second nitrogen atom. Accordingly, in the (2-1) compound according to the embodiment, the empty p-orbital of the boron atom can be protected by a steric effect, and the trigonal planar structure of the boron atom can be effectively maintained. Accordingly, the (2-1) compound according to the embodiment may have improved material stability, thereby preventing material deterioration. Since the (2-1) compound inhibits intermolecular interactions, the occurrence of phenomena such as aggregation, intermolecular excimer formation, or intermolecular exciplex formation may be reduced, and thus the luminous efficiency of the light-emitting element ED including the (2-1) compound may be increased.

[0449] The emission layer EML according to the embodiment includes a first emission layer EML1 that emits light through thermally activated delayed fluorescence and a second emission layer EML2 that emits light through triplet-triplet annihilation, thereby increasing the service life characteristics of the light-emitting element ED including the emission layer EML. The first emission layer EML1 emits light through thermally activated delayed fluorescence of reverse intersystem crossing (RISC) between the lowest excited triplet energy level (T1) and the lowest excited singlet energy level (S1) (where triplet excitons can accumulate according to the rate of RISC). The second emission layer EML2 emits light through triplet-triplet annihilation of the collision of triplet excitons. Triplet-triplet energy transfer, such as Dexter energy transfer, may occur between the first emission layer EML1 and the second emission layer EML2, and the triplet excitons of the second light-emitting host transferred to the second emission layer EML2 may generate singlet excitons through triplet-triplet annihilation, and the singlet excitons may be transferred to the second light-emitting dopant of the second emission layer EML2 to emit light. Since the lowest excited triplet energy level (T1) of the (2-1) compound included in the second emission layer EML2 according to the embodiment is in the range of about 1.5 eV to about 2.1 eV, the Dexter energy transferred to the second emission layer EML2 is dominant compared to the non-radiative decay of the triplet excitons in the first emission layer EML1. When only the first emission layer EML1 that emits light through thermally activated delayed fluorescence is included, the luminous efficiency and service life of the light-emitting element ED may deteriorate due to the accumulation of triplet excitons. However, the emission layer EML according to the embodiment further includes the second emission layer EML2, thereby increasing the service life characteristics of the light-emitting element ED and improving the reliability of the display device.

[0450] The emission spectrum of the (2-1) compound represented by Formula 2 may have a full width at quarter maximum (FWQM) in the range of about 10 nm to about 50 nm. For example, the emission spectrum of the (2-1) compound represented by Formula 2 may have a FWQM in the range of about 20 nm to about 40 nm. The emission spectrum of the (2-1) compound represented by Formula 2 may exhibit a FWQM within the above range, thereby improving the luminous efficiency when applied to the light-emitting element ED.

[0451] The second emission layer EML2 may include the (2-1) compound according to an embodiment. The second emission layer EML2 may include a second light-emitting host and a second light-emitting dopant doped into the second light-emitting host. The second light-emitting dopant may include the (2-1) compound according to an embodiment. The second emission layer EML2 may emit fluorescence through triplet-triplet annihilation, and the (2-1) compound included in the second emission layer EML2 may be used as a delayed fluorescence dopant using triplet-triplet annihilation. For example, in the light-emitting element ED, the second emission layer EML2 may include at least one (2-1) compound selected from the group 2-1 of compounds as described above as a delayed fluorescence dopant.

[0452] The (2-1) compound represented by Formula 2 may be a luminescent material having a central wavelength in the range of about 430 nm to about 490 nm. For example, the (2-1) compound represented by Formula 2 may be a delayed fluorescence dopant using triplet-triplet annihilation. However, the embodiment is not limited thereto, and the (2-1) compound may be used as a dopant material that emits light in various wavelength regions, such as a red emission dopant or a green emission dopant.

[0453] The color of the light emitted from the second emission layer EML2 of the light-emitting element ED may be substantially the same as or similar to the color of the light emitted from the first emission layer EML1. For example, the first emission layer EML1 may emit blue light, and the second emission layer EML2 may emit blue light. The first emission layer EML1 and the second emission layer EML2 of the light-emitting element ED may each emit blue light having a wavelength equal to or less than about 490 nm. However, the embodiment is not limited thereto, and the first emission layer EML1 and the second emission layer EML2 may each independently emit green light or red light.

[0454] In an embodiment, the second emission layer EML2 may include a variety of compounds. The second emission layer EML2 may include a (2-1) compound represented by Formula 2, and may further include a (2-2) compound represented by Formula E-1. For example, the second emission layer EML2 may include a (2-1) compound represented by Formula 2 and a (2-2) compound represented by Formula E-1. In an embodiment, the second emission layer EML2 may consist of: a (2-1) compound represented by Formula 2 and a (2-2) compound represented by Formula E-1.

[0455] In an embodiment, the second emission layer EML2 may include a (2-2) compound represented by Formula E-1. In an embodiment, the second emission layer EML2 may include a second light-emitting host, and the second light-emitting host may include the (2-2) compound. In an embodiment, the (2-2) compound may be used as a fluorescent host material in the second emission layer EML2.

[0456] [Formula E-1]

[0457]

[0458] In Formula E-1, R 31 to R 40 may each independently be a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted silyl group, a substituted or unsubstituted thio group, a substituted or unsubstituted oxy group, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring carbon atoms, or bonded to an adjacent group to form a ring. For example, R 31 to R 40 may be bonded to an adjacent group to form a saturated hydrocarbon ring, an unsaturated hydrocarbon ring, a saturated heterocycle, or an unsaturated heterocycle.

[0459] In Formula E-1, c and d may each independently be an integer selected from 0 to 5.

[0460] In an embodiment, the (2-2) compound represented by Formula E-1 may be any compound selected from Compound E1 to Compound E20. In an embodiment, in the light-emitting element ED, the (2-2) compound may include at least one compound selected from Compound E1 to Compound E20:

[0461]

[0462]

[0463] In such as Figures 3 to 6In the light-emitting element ED according to the embodiment described in each of them, the emission layer EML may include the compound of (1-1) and the compound of (2-1) as described above, and in addition to the compound of (1-1) and the compound of (2-1), the emission layer EML may further include a host in the related art and a dopant in the related art.

[0464] In an embodiment, the emission layer EML may further include a compound represented by Formula E-2a or Formula E-2b. The compound represented by Formula E-2a or Formula E-2b can be used as a phosphorescent host material.

[0465] [Formula E-2a]

[0466]

[0467] In Formula E-2a, a may be an integer selected from 0 to 10; and La may be a direct-connected, substituted or unsubstituted arylene having 6 to 30 ring-forming carbon atoms or a substituted or unsubstituted heteroarylene having 2 to 30 ring-forming carbon atoms. When a is 2 or more, a plurality of La groups may each independently be a substituted or unsubstituted arylene having 6 to 30 ring-forming carbon atoms or a substituted or unsubstituted heteroarylene having 2 to 30 ring-forming carbon atoms.

[0468] In Formula E-2a, A1 to A5 may each independently be N or C(R i ). In Formula E-2a, R a to R i may each independently be a hydrogen atom, a deuterium atom, a substituted or unsubstituted amino group, a substituted or unsubstituted thio group, a substituted or unsubstituted oxy 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 aryl group having 6 to 30 ring-forming carbon atoms or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, or bonded to an adjacent group to form a ring. For example, R a to R i may be bonded to an adjacent group to form a hydrocarbon ring or a heterocyclic ring containing N, O, S, etc. as ring-forming atoms.

[0469] In Formula E-2a, two or three of A1 to A5 may each be N, and the remainder of A1 to A5 may each independently be C(R i ).

[0470] [Formula E-2b]

[0471]

[0472] In formula E-2b, Cbz1 and Cbz2 can each independently be an unsubstituted carbazolyl group or a carbazolyl group substituted with an aryl group having 6 to 30 ring carbon atoms. In formula E-2b, L b can be a direct bond, 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. In formula E-2b, b can be an integer selected from 0 to 10. When b is 2 or greater, multiple L b groups can each independently be 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.

[0473] In an embodiment, the compound represented by formula E-2a or formula E-2b can be any compound selected from the group of compounds E-2. However, the compounds listed in the group of compounds E-2 are only examples, and the compound represented by formula E-2a or formula E-2b is not limited to the group of compounds E-2:

[0474] [Group of compounds E-2]

[0475]

[0476]

[0477] The emission layer EML may further include materials in the relevant art as host materials. For example, the emission layer EML may include at least one of bis(4-(9H-carbazol-9-yl)phenyl)diphenylsilane (BCPDS), (4-(1-(4-(diphenylamino)phenyl)cyclohexyl)phenyl)diphenyl-phosphine oxide (POPCPA), bis[2-(diphenylphosphino)phenyl]ether oxide (DPEPO), 4,4'-bis(N-carbazolyl)-1,1'-biphenyl (CBP), 1,3-bis(N-carbazolyl)benzene (mCP), 2,8-bis(diphenylphosphoryl)dibenzofuran (PPF), 4,4',4''-tris(N-carbazolyl)triphenylamine (TCTA), and 1,3,5-tris(1-phenyl-1H-benzo[d]imidazol-2-yl)benzene (TPBi) as host materials. However, the embodiments are not limited thereto. For example, tris(8-hydroxyquinoline)aluminum (Alq3), 9,10-bis(naphthalen-2-yl)anthracene (ADN), 2-tert-butyl-9,10-bis(naphthalen-2-yl)anthracene (TBADN), stilbenylarene (DSA), 4,4'-bis(9-carbazolyl)-2,2'-dimethyl-biphenyl (CDBP), 2-methyl-9,10-bis(naphthalen-2-yl)anthracene (MADN), hexaphenylcyclotriphosphazene (CP1), 1,4-bis(triphenylsilyl)benzene (UGH2), hexaphenylcyclotrisiloxane (DPSiO3), octaphenylcyclotetrasiloxane (DPSiO4), etc. can be used as host materials.

[0478] In an embodiment, the emission layer EML may further include a compound represented by Formula M-a. The compound represented by Formula M-a can be used as a phosphorescent dopant material.

[0479] [Formula M-a]

[0480]

[0481] In Formula M-a, Y1 to Y4 and Z1 to Z4 may each independently be C(R1) or N; R1 to R4 may each independently be a hydrogen atom, a deuterium atom, a substituted or unsubstituted amino group, a substituted or unsubstituted thio group, a substituted or unsubstituted oxy 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 aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring carbon atoms, or bonded to an adjacent group to form a ring. In Formula M-a, m may be 0 or 1, and n may be 2 or 3. In Formula M-a, when m is 0, n may be 3, and when m is 1, n may be 2.

[0482] In an embodiment, the compound represented by formula M-a can be any compound selected from Compound M-a1 to Compound M-a25. However, Compound M-a1 to Compound M-a25 are only examples, and the compound represented by formula M-a is not limited to Compound M-a1 to Compound M-a25:

[0483]

[0484]

[0485] In an embodiment, the emission layer EML may further include a compound represented by one of formula F-a to formula F-c. The compound represented by one of formula F-a to formula F-c can be used as a fluorescent dopant material.

[0486] [Formula F-a]

[0487]

[0488] In formula F-a, two of R a to R j may each independently be substituted with a group represented by *—NAr1Ar2. The remaining groups of R a to R j that are not substituted with a group represented by *—NAr1Ar2 may 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 2 to 30 ring carbon atoms.

[0489] In the group represented by *—NAr1Ar2, Ar1 and Ar2 may each independently be a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms or a substituted or unsubstituted heteroaryl group having 2 to 30 ring carbon atoms. For example, at least one of Ar1 and Ar2 may each independently be a heteroaryl group containing O or S as a ring atom.

[0490] [Formula F-b]

[0491]

[0492] In formula F-b, R a and R bEach may independently be a hydrogen atom, a deuterium atom, 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 aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring carbon atoms, or bonded to an adjacent group to form a ring. In Formula F-b, Ar1 to Ar4 may each independently be a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms or a substituted or unsubstituted heteroaryl group having 2 to 30 ring carbon atoms. For example, at least one of Ar1 to Ar4 may each independently be a heteroaryl group containing O or S as a ring atom.

[0493] In Formula F-b, U and V may each independently be a substituted or unsubstituted hydrocarbon ring having 5 to 30 ring carbon atoms or a substituted or unsubstituted heterocyclic ring having 2 to 30 ring carbon atoms.

[0494] In Formula F-b, the number of rings represented by U and V may each independently be 0 or 1. When the number of U or V is 1, a fused ring may be present at the portion indicated by U or V, respectively, and when the number of U or V is 0, a fused ring may not be present at the portion indicated by U or V, respectively. When the number of U is 0 and the number of V is 1, or when the number of U is 1 and the number of V is 0, the fused ring having a fluorene nucleus in Formula F-b may be a cyclic compound having four rings. When the numbers of U and V are each 0, the fused ring having a fluorene nucleus in Formula F-b may be a cyclic compound having three rings. When the numbers of U and V are each 1, the fused ring having a fluorene nucleus in Formula F-b may be a cyclic compound having five rings.

[0495] [Formula F-c]

[0496]

[0497] In Formula F-c, A1 and A2 may each independently be O, S, Se or N(R m ); and R m may be a hydrogen atom, a deuterium atom, 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 2 to 30 ring carbon atoms. In Formula F-c, R1 to R 11 may 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 boron group, a substituted or unsubstituted oxy group, a substituted or unsubstituted thio 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 2 to 30 ring carbon atoms, or bonded to an adjacent group to form a ring.

[0498] In formula F-c, A1 and A2 may each independently bond to a substituent of an adjacent ring to form a fused ring. For example, when A1 and A2 are each independently N(R m ), A1 may bond to R4 or R5 to form a fused ring, and / or A2 may bond to R7 or R8 to form a fused ring.

[0499] In an embodiment, the emissive layer EML may further include a styryl derivative (e.g., 1,4-bis[2-(3-N-ethylcarbazolyl)vinyl]benzene (BCzVB), 4-(di-p-tolylamino)-4'-[(di-p-tolylamino)styryl]stilbene (DPAVB), N-(4-((E)-2-(6-((E)-4-(diphenylamino)styryl)naphthalen-2-yl)vinyl)phenyl)-N-phenylaniline (N-BDAVBi), and 4,4'-bis[2-(4-(N,N-diphenylamino)phenyl)vinyl]biphenyl (DPAVBi)), perylene or its derivative (e.g., 2,5,8,11-tetra-tert-butylperylene (TBP)), pyrene or its derivative (e.g., 1,1'-dipyrene, 1,4-dipyrenylbenzene, 1,4-bis(N,N-diphenylamino)pyrene), etc. as a dopant material in the relevant art.

[0500] The emissive layer EML may further include a phosphorescent dopant material in the relevant art. For example, metal complexes containing iridium (Ir), platinum (Pt), osmium (Os), gold (Au), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu), terbium (Tb), or thulium (Tm) can be used as phosphorescent dopants. For example, bis(4,6-difluorophenylpyridinato-N,C2')iridium(III) picolinate (FIrpic), bis(2,4-difluorophenylpyridinato)-tetrakis(1-pyrazolyl)borate iridium(III) (FIr6), or platinum octaethylporphyrin (PtOEP) can be used as phosphorescent dopants. However, the embodiments are not limited thereto.

[0501] In an embodiment, the emissive layer EML may include quantum dots. The quantum dots may include a Group II-VI compound, a Group III-VI compound, a Group I-III-VI compound, a Group III-V compound, a Group III-II-V compound, a Group IV-VI compound, a Group IV element, a Group IV compound, or any combination thereof.

[0502] Examples of II-VI group compounds may include: binary compounds such as CdSe, CdTe, CdS, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, MgSe, MgS and mixtures thereof; ternary compounds such as CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, MgZnSe, MgZnS and mixtures thereof; quaternary compounds such as HgZnTeS, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe and mixtures thereof; and any combination thereof.

[0503] Examples of III-VI group compounds may include: binary compounds such as In2S3 or In2Se3; ternary compounds such as InGaS3 or InGaSe3; and any combination thereof.

[0504] Examples of I-III-VI group compounds may include: ternary compounds such as AgInS, AgInS2, CuInS, CuInS2, AgGaS2, CuGaS2, CuGaO2, AgGaO2, AgAlO2 and mixtures thereof; quaternary compounds such as AgInGaS2 or CuInGaS2; and any combination thereof.

[0505] Examples of III-V group compounds may include: binary compounds such as GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb and mixtures thereof; ternary compounds such as GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InGaP, InAlP, InNP, InNAs, InNSb, InPAs, InPSb and mixtures thereof; quaternary compounds such as GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, InAlPSb and mixtures thereof; and any combination thereof. In an embodiment, the III-V group compound may further include a Group II element. Examples of III-II-V group compounds may include InZnP and the like.

[0506] Examples of group IV-VI compounds may include: binary compounds such as SnS, SnSe, SnTe, PbS, PbSe, PbTe, and mixtures thereof; ternary compounds such as SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, and mixtures thereof; quaternary compounds such as SnPbSSe, SnPbSeTe, SnPbSTe, and mixtures thereof; and any combination thereof. Examples of group IV elements may include Si, Ge, and mixtures thereof. Examples of group IV compounds may include binary compounds such as SiC, SiGe, and mixtures thereof.

[0507] Each element included in a compound (e.g., a binary compound, a ternary compound, or a quaternary compound) may exist in the particles with a uniform concentration distribution or a non-uniform concentration distribution. For example, a formula may indicate the elements included in the compound, and the elemental ratio of the compound may be varied. For example, AgInGaS2 may indicate AgIn x Ga 1-x S2 (where 0 < x < 1).

[0508] In an embodiment, the quantum dots may have a single structure, in which the concentration of each element included in the quantum dots is uniform. In another embodiment, the quantum dots may have a core-shell structure, in which a quantum dot material surrounds another quantum dot. For example, the material included in the core may be different from the material included in the shell.

[0509] The shell of the quantum dots may serve as a protective layer for preventing chemical denaturation of the core to maintain semiconductor characteristics, and / or may serve as a charging layer for imparting electrophoretic characteristics to the quantum dots. The shell may have a single-layer structure or a multi-layer structure. The interface between the core and the shell may have a concentration gradient in which the concentration of the elements present in the shell decreases toward the center of the core.

[0510] In an embodiment, the quantum dots may have a core-shell structure as described above, the core-shell structure including a core containing nanocrystals and a shell surrounding the core. Examples of the shell of the quantum dots may include metal oxides, non-metal oxides, semiconductor compounds, or any combination thereof.

[0511] Examples of the metal oxides or non-metal oxides may include: binary compounds such as SiO2, Al2O3, TiO2, ZnO, MnO, Mn2O3, Mn3O4, CuO, FeO, Fe2O3, Fe3O4, CoO, Co3O4, or NiO; and ternary compounds such as MgAl2O4, CoFe2O4, NiFe2O4, or CoMn2O4, but the embodiments are not limited thereto.

[0512] Examples of semiconductor compounds may include CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnSeS, ZnTeS, GaAs, GaP, GaSb, HgS, HgSe, HgTe, InAs, InP, InGaP, InSb, AlAs, AlP, AlSb, etc., but embodiments are not limited thereto.

[0513] The quantum dots may have a full width at half maximum (FWHM) of an emission wavelength spectrum equal to or less than about 45 nm. For example, the quantum dots may have an FWHM of an emission wavelength spectrum equal to or less than about 40 nm. For example, the quantum dots may have an FWHM of an emission wavelength spectrum equal to or less than about 30 nm. Color purity and / or color reproducibility may be improved within any of the above ranges. The light emitted by the quantum dots may be emitted in all directions so that a wide viewing angle may be improved.

[0514] The form of the quantum dots is not particularly limited and may be any form used in the relevant art. For example, the quantum dots may have a spherical shape, a cone shape, a multi-arm shape, or a cube shape, or the quantum dots may be in the form of nanoparticles, nanotubes, nanowires, nanofibers, nanoplates, etc.

[0515] As the size of the quantum dots or the elemental ratio in the quantum dot compound is adjusted, the band gap can be controlled accordingly so that light in various wavelength ranges can be provided by the quantum dot emission layer. Therefore, by using quantum dots as described above (e.g., using quantum dots of different sizes or having different elemental ratios in the quantum dot compound), a light-emitting element ED that emits light in various wavelength ranges can be implemented. For example, the size of the quantum dots or the elemental ratio of the quantum dot compound can be adjusted to emit red, green, and / or blue light. For example, the quantum dots can be configured to emit white light by combining light of various colors.

[0516] In the light-emitting element ED according to an embodiment shown in each of Figures 3 to 6 the electron transport region ETR may be provided on the emission layer EML. The electron transport region ETR may include at least one of a hole blocking layer HBL, an electron transport layer ETL, and an electron injection layer EIL, but embodiments are not limited thereto.

[0517] The electron transport region ETR may have a single-layer structure composed of a single layer (composed of a single material), a single-layer structure composed of a single layer including different materials, or a multi-layer structure including multiple layers containing different materials.

[0518] 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 may have a single-layer structure formed of an electron injection material and an electron transport material. In an embodiment, the electron transport region ETR may have a single-layer structure formed of different materials, or may have a structure in which an electron transport layer ETL / electron injection layer EIL or a hole blocking layer HBL / electron transport layer ETL / electron injection layer EIL is stacked from the emission layer EML in the order described above, but the embodiment is not limited thereto. The electron transport region ETR may have, for example, a thickness in the range of about to about .

[0519] The electron transport region ETR can be formed using various methods such as vacuum deposition, spin coating, casting, Langmuir-Blodgett (LB) method, inkjet printing, laser printing, and laser-induced thermal imaging (LITI) method.

[0520] In the light-emitting device ED according to an embodiment, the electron transport region ETR may include a compound represented by Formula ET-2:

[0521] [Formula ET-2]

[0522]

[0523] In Formula ET-2, at least one of X1 to X3 may each be N; and the remainder of X1 to X3 may each independently be C(R a ). In Formula ET-2, R a may be a hydrogen atom, a deuterium atom, 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 2 to 30 ring carbon atoms. In Formula ET-2, Ar1 to Ar3 may each independently be a hydrogen atom, a deuterium atom, 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 2 to 30 ring carbon atoms.

[0524] In Formula ET-2, a to c may each independently be an integer selected from 0 to 10. In Formula ET-2, L1 to L3 may each independently be a direct bond, 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. When a to c are each 2 or greater, the multiple groups of each of L1 to L3 may each independently be 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.

[0525] The electron transport region ETR may include anthracene compounds. However, the embodiments are not limited thereto, and the electron transport region ETR may include, for example, tris(8-hydroxyquinoline)aluminum (Alq3), 1,3,5-tris[(3-pyridinyl)-benzene-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-dinaphthoanthracene, 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), 4-(naphthalen-1-yl)-3,5-diphenyl-4H-1,2,4-triazole (NTAZ), 2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole ( t Bu-PBD), bis(2-methyl-8-hydroxyquinoline-N1,O8)-(1,1'-biphenyl-4-ol)aluminum (BAlq), bis(benzoquinolin-10-ol)beryllium (Bebq2), 9,10-di(naphthalen-2-yl)anthracene (ADN), 1,3-bis[3,5-bis(pyridin-3-yl)phenyl]benzene (BmPyPhB), or a mixture thereof.

[0526] In an embodiment, the electron transport region ETR may include at least one compound selected from Compound ET1 to Compound ET36:

[0527]

[0528]

[0529]

[0530]

[0531] In an embodiment, the electron transport region ETR may include: metal halides (such as LiF, NaCl, CsF, RbCl, RbI, CuI, and KI); lanthanide elements (such as Yb); or co-deposited materials of metal halides and lanthanide elements. For example, the electron transport region ETR may include KI:Yb, RbI:Yb, LiF:Yb, etc. as co-deposited materials. The electron transport region ETR may include metal oxides (such as Li2O or BaO), or lithium 8-hydroxyquinoline (Liq), etc., but the embodiments are not limited thereto. The electron transport region ETR may also be formed of a mixture of an electron transport material and an insulating organometallic salt. The insulating organometallic salt may be a material having a band gap equal to or greater than about 4 eV. For example, the insulating organometallic salt may include metal acetates, metal benzoates, metal acetoacetates, metal acetylacetonates, or metal stearates.

[0532] In addition to the above materials, the electron transport region ETR may further include at least one of 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), diphenyl(4-(triphenylsilyl)phenyl)phosphine oxide (TSPO1), and 4,7-diphenyl-1,10-phenanthroline (Bphen), but the embodiments are not limited thereto.

[0533] The electron transport region ETR may include the above compounds of the electron transport region ETR in at least one of the electron injection layer EIL, the electron transport layer ETL, and the hole blocking layer HBL.

[0534] When the electron transport region ETR includes the electron transport layer ETL, the electron transport layer ETL may have a thickness in the range of about to about . For example, the electron transport layer ETL may have a thickness in the range of about to about . If the thickness of the electron transport layer ETL satisfies the foregoing range, satisfactory electron transport characteristics can be obtained without significantly increasing the driving voltage. When the electron transport region ETR includes the electron injection layer EIL, the electron injection layer EIL may have a thickness in the range of about to about . For example, the electron injection layer EIL may have a thickness in the range of about to about . If the thickness of the electron injection layer EIL satisfies the above range, satisfactory electron injection characteristics can be obtained without significantly increasing the driving voltage.

[0535] The second electrode EL2 can be provided on the electron transport region ETR. The second electrode EL2 can be a common electrode. The second electrode EL2 can be a cathode or an anode, but the embodiments are not limited thereto. For example, when the first electrode EL1 is an anode, the second electrode EL2 can be a cathode, and when the first electrode EL1 is a cathode, the second electrode EL2 can be an anode.

[0536] The second electrode EL2 can be a transmissive electrode, a transflective electrode, or a reflective electrode. When the second electrode EL2 is a transmissive electrode, the second electrode EL2 can be formed of a transparent metal oxide, such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium tin zinc oxide (ITZO), etc.

[0537] When the second electrode EL2 is a transflective electrode or a reflective electrode, the second electrode EL2 can include Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF, Mo, Ti, Yb, W, compounds thereof, or mixtures thereof (e.g., AgMg, AgYb, or MgYb), or materials having a multilayer structure, such as LiF / Ca (a stacked structure of LiF and Ca) or LiF / Al (a stacked structure of LiF and Al). In an embodiment, the second electrode EL2 can have a multilayer structure that includes a reflective film or a transflective film formed of the above materials, and a transparent conductive film formed of ITO, IZO, ZnO, ITZO, etc. For example, the second electrode EL2 can include one of the above metal materials, a combination of at least two of the above metal materials, or oxides of the above metal materials, etc.

[0538] Although not shown in the drawings, the second electrode EL2 can be electrically connected to an auxiliary electrode. If the second electrode EL2 is electrically connected to the auxiliary electrode, the resistance of the second electrode EL2 can be reduced.

[0539] In an embodiment, the light-emitting element ED can further include a capping layer CPL provided on the second electrode EL2. The capping layer CPL can have a multilayer structure or a single-layer structure.

[0540] In an embodiment, the capping layer CPL can include an organic layer or an inorganic layer. For example, when the capping layer CPL contains an inorganic material, the inorganic material can include an alkali metal compound (e.g., LiF), an alkaline earth metal compound (e.g., MgF2), SiON, SiN x , SiO y etc.

[0541] For example, when the capping layer CPL includes an organic material, the organic material may include N,N’-bis(naphthalen-1-yl)-N,N’-bis(phenyl)-2,2’-dimethylbenzidine (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(N-carbazolyl)triphenylamine (TCTA), etc., or may include an epoxy resin or an acrylate (e.g., methacrylate). However, the embodiments are not limited thereto, and the capping layer CPL may include at least one of Compound P1 to Compound P5:

[0542]

[0543] The refractive index of the capping layer CPL may be equal to or greater than about 1.6. For example, with respect to light in the wavelength range of about 550 nm to about 660 nm, the refractive index of the capping layer CPL may be equal to or greater than about 1.6.

[0544] Figures 7 to 10 Each is a schematic cross-sectional view of a display device according to an embodiment. When describing the display device according to an embodiment as shown in Figures 7 to 10 the features already described above with reference to Figures 1 to 6 will not be described again, and different features will be explained.

[0545] Referring to Figure 7 , a display device DD-a according to an embodiment may include: a display panel DP including a display device layer DP-ED, a light control layer CCL provided on the display panel DP, and a color filter layer CFL. In the embodiment shown in Figure 7 , the display panel DP may include a base layer BS, a circuit layer DP-CL provided on the base layer BS, and a display device layer DP-ED, and the display device layer DP-ED may include a light-emitting element ED-1.

[0546] The light-emitting element ED-1 may include a first electrode EL1, a hole transport region HTR provided on the first electrode EL1, a first emission layer EML1 provided on the hole transport region HTR, a second emission layer EML2 provided on the first emission layer EML1, an electron transport region ETR provided on the second emission layer EML2, and a second electrode EL2 provided on the electron transport region ETR. In the embodiment, Figure 7 the structure of the light-emitting element ED-1 shown in Figures 3 to 6 may be the same as the structure of the light-emitting element ED according to one of the above-mentioned

[0547] The first emission layer EML1 of the light-emitting element ED-1 included in the display device DD-a according to the embodiment may include the compound of (1-1) as described above, and the second emission layer EML2 may include the compound of (2-1) as described above.

[0548] Reference Figure 7 , the first emission layer EML1 and the second emission layer EML2 may be provided in a stacked structure in the opening OH defined in the pixel defining film PDL. For example, the first emission layer EML1 and the second emission layer EML2 each defined by the pixel defining film PDL and provided corresponding to each of the light-emitting regions PXA-R, PXA-G, and PXA-B may emit light in the same wavelength range. In the display device DD-a, the first emission layer EML1 and the second emission layer EML2 may each emit blue light. Although not shown in the drawings, in the embodiment, the first emission layer EML1 and the second emission layer EML2 may each be provided as a common layer for all the light-emitting regions PXA-R, PXA-G, and PXA-B.

[0549] The light control layer CCL may be provided on the display panel DP. The light control layer CCL may include a light converter. The light converter may be a quantum dot or a phosphor, etc. The light converter may convert the wavelength of the provided light and emit the resulting light. For example, the light control layer CCL may be a layer including quantum dots or a layer including phosphors.

[0550] The light control layer CCL may include light control components CCP1, CCP2, and CCP3. The light control components CCP1, CCP2, and CCP3 may be spaced apart from each other.

[0551] Reference Figure 7 , the dividing pattern BMP may be provided between the light control components CCP1, CCP2, and CCP3 spaced apart from each other, but the embodiment is not limited thereto. In Figure 7 it is shown that the dividing pattern BMP does not overlap with the light control components CCP1, CCP2, and CCP3, but the edges of the light control components CCP1, CCP2, and CCP3 may overlap at least a part of the dividing pattern BMP.

[0552] The light control layer CCL may include a first light control component CCP1 containing a first quantum dot QD1 that converts the first color light provided from the light-emitting element ED into a second color light; a second light control component CCP2 containing a second quantum dot QD2 that converts the first color light into a third color light; and a third light control component CCP3 that transmits the first color light.

[0553] In an embodiment, the first light control component CCP1 may provide red light as the second color light, and the second light control component CCP2 may provide green light as the third color light. The third light control component CCP3 may provide blue light by transmitting blue light as the first color light provided from the light emitting element ED. For example, the first quantum dot QD1 may be a red quantum dot, and the second quantum dot QD2 may be a green quantum dot. The quantum dots QD1 and QD2 may each be a quantum dot as described above.

[0554] The light control layer CCL may further include a scatterer SP. The first light control component CCP1 may include the first quantum dot QD1 and the scatterer SP, the second light control component CCP2 may include the second quantum dot QD2 and the scatterer SP, and the third light control component CCP3 may not include any quantum dots, but may include the scatterer SP.

[0555] The scatterer SP may be inorganic particles. For example, the scatterer SP may include at least one of TiO2, ZnO, Al2O3, SiO2, and hollow silica. The scatterer SP may include one of TiO2, ZnO, Al2O3, SiO2, and hollow silica, or may be a mixture of at least two materials selected from TiO2, ZnO, Al2O3, SiO2, and hollow silica.

[0556] The first light control component CCP1, the second light control component CCP2, and the third light control component CCP3 may include base resins BR1, BR2, and BR3 in which the quantum dots QD1 and QD2 and the scatterer SP are dispersed. In an embodiment, the first light control component CCP1 may include the first quantum dot QD1 and the scatterer SP dispersed in the first base resin BR1, the second light control component CCP2 may include the second quantum dot QD2 and the scatterer SP dispersed in the second base resin BR2, and the third light control component CCP3 may include the scatterer SP dispersed in the third base resin BR3.

[0557] The base resins BR1, BR2, and BR3 are media in which the quantum dots QD1 and QD2 and the scatterer SP are dispersed, and may include various resin compositions that may be referred to as binders. For example, the base resins BR1, BR2, and BR3 may be acrylic resins, urethane resins, silicone resins, epoxy resins, etc. The base resins BR1, BR2, and BR3 may each be transparent resins. In an embodiment, the first base resin BR1, the second base resin BR2, and the third base resin BR3 may be the same as or different from each other.

[0558] The light control layer CCL may include a barrier layer BFL1. The barrier layer BFL1 may prevent the penetration of moisture and / or oxygen (hereinafter referred to as "moisture / oxygen"). The barrier layer BFL1 may block the light control components CCP1, CCP2, and CCP3 from being exposed to moisture / oxygen. The barrier layer BFL1 may cover the light control components CCP1, CCP2, and CCP3. In an embodiment, a barrier layer BFL2 may be provided between the light control components CCP1, CCP2, and CCP3 and the color filters CF1, CF2, and CF3.

[0559] The barrier layers BFL1 and BFL2 may each independently include at least one inorganic layer. For example, the barrier layers BFL1 and BFL2 may each independently include an inorganic material. For example, the barrier layers BFL1 and BFL2 may each independently include silicon nitride, aluminum nitride, zirconium nitride, titanium nitride, hafnium nitride, tantalum nitride, silicon oxide, aluminum oxide, titanium oxide, tin oxide, cerium oxide, silicon oxynitride, a metal thin film ensuring light transmittance, etc. The barrier layers BFL1 and BFL2 may each independently further include an organic film. The barrier layers BFL1 and BFL2 may be formed of a single layer or multiple layers.

[0560] In the display device DD-a, a color filter layer CFL may be disposed on the light control layer CCL. In an embodiment, the color filter layer CFL may be directly disposed on the light control layer CCL. For example, the barrier layer BFL2 may be omitted.

[0561] The color filter layer CFL may include color filters CF1, CF2, and CF3. The color filter layer CFL may include a first color filter CF1 that transmits second-color light, a second color filter CF2 that transmits third-color light, and a third color filter CF3 that transmits first-color light. For example, the first color filter CF1 may be a red color filter, the second color filter CF2 may be a green color filter, and the third color filter CF3 may be a blue color filter. Each of the color filters CF1, CF2, and CF3 may include a polymer photosensitive resin and a pigment or a dye. The first color filter CF1 may include a red pigment or a red dye, the second color filter CF2 may include a green pigment or a green dye, and the third color filter CF3 may include a blue pigment or a blue dye.

[0562] However, the embodiment is not limited thereto, and the third color filter CF3 may not include a pigment or a dye. The third color filter CF3 may include a polymer photosensitive resin and may not include a pigment or a dye. The third color filter CF3 may be transparent. The third color filter CF3 may be formed of a transparent photosensitive resin.

[0563] In an embodiment, the first color filter CF1 and the second color filter CF2 may each be a yellow color filter. The first color filter CF1 and the second color filter CF2 may not be provided as separate color filters and may be provided as an integrated color filter.

[0564] Although not shown in the drawings, in an embodiment, the color filter layer CFL may further include a light-shielding member (not shown). The light-shielding member (not shown) may be a black matrix. The light-shielding member (not shown) may include an organic light-shielding material or an inorganic light-shielding material each including a black pigment or a black dye. The light-shielding member (not shown) may prevent light leakage and may separate adjacent color filters CF1, CF2, and CF3.

[0565] The first color filter CF1, the second color filter CF2, and the third color filter CF3 may be arranged to correspond to a red light-emitting region PXA-R, a green light-emitting region PXA-G, and a blue light-emitting region PXA-B, respectively.

[0566] The base substrate BL may be disposed on the color filter layer CFL. The base substrate BL may provide a base surface on which the color filter layer CFL, the light control layer CCL, etc. are disposed. The base substrate BL may be a glass substrate, a metal substrate, a plastic substrate, etc. However, the embodiment is not limited thereto, and the base substrate BL may include an inorganic layer, an organic layer, or a composite material layer. Although not shown in the drawings, in an embodiment, the base substrate BL may be omitted.

[0567] Figure 8 FIG. is a schematic cross-sectional view of a part of a display device according to an embodiment. In a display device DD-TD according to an embodiment, the light-emitting element ED-BT may include light-emitting structures OL-B1, OL-B2, and OL-B3. The light-emitting element ED-BT may include a first electrode EL1 and a second electrode EL2 facing each other, and light-emitting structures OL-B1, OL-B2, and OL-B3 stacked in the thickness direction between the first electrode EL1 and the second electrode EL2. The light-emitting structures OL-B1, OL-B2, and OL-B3 may each include a hole transport region HTR (see Figure 7 ) disposed between the first electrode EL1 and the second electrode EL2 in the following order, a first and a second emission layer EML1 and EML2 (see Figure 7 ), and an electron transport region ETR (see Figure 7 ).

[0568] Therefore, the light-emitting element ED-BT included in the display device DD-TD may be a light-emitting element having a tandem structure including a plurality of first emission layers EML1 and a plurality of second emission layers EML2.

[0569] In Figure 8In the embodiments shown, the light emitted from the light-emitting structures OL-B1, OL-B2, and OL-B3 may each be blue light. However, the embodiments are not limited thereto, and the light emitted from each of the light-emitting structures OL-B1, OL-B2, and OL-B3 may have different wavelength ranges from each other. For example, the light-emitting element ED-BT including the light-emitting structures OL-B1, OL-B2, and OL-B3 that emit light having different wavelength ranges from each other may emit white light.

[0570] The charge generation layers CGL1 and CGL2 may each be disposed between two adjacent ones of the light-emitting structures OL-B1, OL-B2, and OL-B3. The charge generation layers CGL1 and CGL2 may each independently include a p-type charge generation layer and / or an n-type charge generation layer.

[0571] The light-emitting structures OL-B1, OL-B2, and OL-B3 included in the display device DD-TD may each include: a first emission layer EML1 including the compound of (1-1) as described above (see Figure 7 ) and a second emission layer EML2 including the compound of (2-1) as described above (see Figure 7 ).

[0572] Figure 9 FIG. is a schematic cross-sectional view of a display device DD-b according to an embodiment. Figure 10 FIG. is a schematic cross-sectional view of a display device DD-c according to an embodiment.

[0573] Reference Figure 9 , the display device DD-b according to an embodiment may include light-emitting elements ED-1, ED-2, and ED-3 in which four emission layers are stacked. Compared with the display device DD shown in Figure 2 , the embodiment shown in Figure 9 is different at least in that the first to third light-emitting elements ED-1, ED-2, and ED-3 each include four emission layers stacked in the thickness direction. In each of the first to third light-emitting elements ED-1, ED-2, and ED-3 of the display device DD-b, the four emission layers may emit light in the same wavelength region.

[0574] The first light-emitting element ED-1 may include a first red emission layer EML1-R1 and EML2-R1 having a structure in which two emission layers are stacked, and a second red emission layer EML1-R2 and EML2-R2 having a structure in which two emission layers are stacked. The first red emission layer EML1-R1 and EML2-R1 may include a (1-1) red emission layer EML1-R1 and a (2-1) red emission layer EML2-R1. The second red emission layer EML1-R2 and EML2-R2 may include a (1-2) red emission layer EML1-R2 and a (2-2) red emission layer EML2-R2. An emission assisting member OG may be disposed between the first red emission layer EML1-R1 and EML2-R1 and the second red emission layer EML1-R2 and EML2-R2, and the emission assisting member OG is between the (1-1) red emission layer EML1-R1 and the (2-2) red emission layer EML2-R2.

[0575] The second light-emitting element ED-2 may include a first green emission layer EML1-G1 and EML2-G1 having a structure in which two emission layers are stacked, and a second green emission layer EML1-G2 and EML2-G2 having a structure in which two emission layers are stacked. The first green emission layer EML1-G1 and EML2-G1 may include a (1-1) green emission layer EML1-G1 and a (2-1) green emission layer EML2-G1. The second green emission layer EML1-G2 and EML2-G2 may include a (1-2) green emission layer EML1-G2 and a (2-2) green emission layer EML2-G2. An emission assisting member OG may be disposed between the first green emission layer EML1-G1 and EML2-G1 and the second green emission layer EML1-G2 and EML2-G2, and the emission assisting member OG is between the (1-1) green emission layer EML1-G1 and the (2-2) green emission layer EML2-G2.

[0576] The third light-emitting element ED-3 may include a first blue emission layer EML1-B1 and EML2-B1 having a structure in which two emission layers are stacked, and a second blue emission layer EML1-B2 and EML2-B2 having a structure in which two emission layers are stacked. The first blue emission layer EML1-B1 and EML2-B1 may include a (1-1) blue emission layer EML1-B1 and a (2-1) blue emission layer EML2-B1. The second blue emission layer EML1-B2 and EML2-B2 may include a (1-2) blue emission layer EML1-B2 and a (2-2) blue emission layer EML2-B2. An emission assisting member OG may be disposed between the first blue emission layer EML1-B1 and EML2-B1 and the second blue emission layer EML1-B2 and EML2-B2, and the emission assisting member OG is between the (1-1) blue emission layer EML1-B1 and the (2-2) blue emission layer EML2-B2.

[0577] The emission assisting member OG may have a single-layer structure or a multi-layer structure. The emission assisting member OG may include a charge generation layer. For example, the emission assisting member OG may include an electron transport region (not shown), a charge generation layer (not shown), and a hole transport region (not shown) that may be stacked in the following order. The emission assisting member OG may be provided as a common layer for the first to third light-emitting elements ED-1, ED-2, and ED-3. However, the embodiments are not limited thereto, and the emission assisting member OG may be provided by patterning in an opening OH defined in the pixel defining film PDL.

[0578] The first red emission layer EML1-R1 and EML2-R1, the first green emission layer EML1-G1 and EML2-G1, and the first blue emission layer EML1-B1 and EML2-B1 may be disposed between the emission assisting member OG and the electron transport region ETR. The second red emission layer EML1-R2 and EML2-R2, the second green emission layer EML1-G2 and EML2-G2, and the second blue emission layer EML1-B2 and EML2-B2 may be disposed between the hole transport region HTR and the emission assisting member OG.

[0579] The first light-emitting element ED-1 may include a first electrode EL1, a hole transport region HTR, second red emission layers EML1-R2 and EML2-R2, an emission assisting member OG, first red emission layers EML1-R1 and EML2-R1, an electron transport region ETR, and a second electrode EL2, which are stacked in the following order. The second light-emitting element ED-2 may include a first electrode EL1, a hole transport region HTR, second green emission layers EML1-G2 and EML2-G2, an emission assisting member OG, first green emission layers EML1-G1 and EML2-G1, an electron transport region ETR, and a second electrode EL2, which are stacked in the following order. The third light-emitting element ED-3 may include a first electrode EL1, a hole transport region HTR, second blue emission layers EML1-B2 and EML2-B2, an emission assisting member OG, first blue emission layers EML1-B1 and EML2-B1, an electron transport region ETR, and a second electrode EL2, which are stacked in the following order.

[0580] The optical assisting layer PL may be disposed on the display device layer DP-ED. The optical assisting layer PL may include a polarization layer. The optical assisting layer PL may be disposed on the display panel DP and may control light reflected from external light at the display panel DP. Although not shown in the drawings, in an embodiment, the optical assisting layer PL may be omitted from the display device DD-b.

[0581] Figure 9 The (1-1) red emission layer EML1-R1, the (1-2) red emission layer EML1-R2, the (1-1) green emission layer EML1-G1, the (1-2) green emission layer EML1-G2, the (1-1) blue emission layer EML1-B1, and the (1-2) blue emission layer EML1-B2 included in the display device DD-b shown in may each correspond to the first emission layer EML1 as described above (see Figure 7 ). At least one of the (1-1) red emission layer EML1-R1, the (1-2) red emission layer EML1-R2, the (1-1) green emission layer EML1-G1, the (1-2) green emission layer EML1-G2, the (1-1) blue emission layer EML1-B1, and the (1-2) blue emission layer EML1-B2 may each independently include the (1-1) compound according to the embodiment as described above. In an embodiment, at least one of the (1-1) blue emission layer EML1-B1 and the (1-2) blue emission layer EML1-B2 may each independently include the (1-1) compound.

[0582] Figure 9The (2-1)st red emission layer EML2-R1, the (2-2)nd red emission layer EML2-R2, the (2-1)st green emission layer EML2-G1, the (2-2)nd green emission layer EML2-G2, the (2-1)st blue emission layer EML2-B1, and the (2-2)nd blue emission layer EML2-B2 included in the display device DD-b shown in [see Figure 7 ) may each correspond to the second emission layer EML2 as described above (see

[0583] One or more of the (2-1)st red emission layer EML2-R1, the (2-2)nd red emission layer EML2-R2, the (2-1)st green emission layer EML2-G1, the (2-2)nd green emission layer EML2-G2, the (2-1)st blue emission layer EML2-B1, and the (2-2)nd blue emission layer EML2-B2 may each independently include the (2-1)st compound according to the embodiment as described above. In an embodiment, one or more of the (2-1)st blue emission layer EML2-B1 and the (2-2)nd blue emission layer EML2-B2 may each independently include the (2-1)st compound.

[0583] Compared with Figure 8 and Figure 9 , Figure 10 the display device DD-c shown differs at least in that it includes four light-emitting structures OL-B1, OL-B2, OL-B3, and OL-C1. The light-emitting element ED-CT may include a first electrode EL1 and a second electrode EL2 facing each other, and first to fourth light-emitting structures OL-B1, OL-B2, OL-B3, and OL-C1 stacked in the thickness direction between the first electrode EL1 and the second electrode EL2. Among the four light-emitting structures, the first to third light-emitting structures OL-B1, OL-B2, and OL-B3 may each emit blue light, and the fourth light-emitting structure OL-C1 may emit green light. However, the embodiment is not limited thereto, and the first to fourth light-emitting structures OL-B1, OL-B2, OL-B3, and OL-C1 may emit light having different wavelength regions from each other.

[0584] The charge generation layers CGL1, CGL2, and CGL3 may each be provided between two adjacent light-emitting structures among the first to fourth light-emitting structures OL-B1, OL-B2, OL-B3, and OL-C1. The charge generation layers CGL1, CGL2, and CGL3 may each independently include a p-type charge generation layer and / or an n-type charge generation layer.

[0585] The light-emitting structures OL-B1, OL-B2, OL-B3, and OL-C1 included in the display device DD-c may each include: a first emission layer EML1 including the (1-1)st compound as described above (see Figure 7) and a second emission layer EML2 including the compound of (2-1) as described above (see Figure 7 ).

[0586] In an embodiment, the electronic device may include: a display device including a plurality of light-emitting elements and a control component for controlling the display device. The electronic device may be a device activated by an electrical signal. The electronic device may include a display device according to various embodiments. Examples of the electronic device may include large electronic devices (such as, a television, a monitor, or a billboard) and medium and small electronic devices (such as, a personal computer, a laptop computer, a personal digital terminal, a display device for a vehicle, a game console, a portable electronic device, or a camera).

[0587] Figure 11 FIG. is a schematic perspective view of a vehicle AM including first to fourth display devices DD-1, DD-2, DD-3, and DD-4. At least one of the first to fourth display devices DD-1, DD-2, DD-3, and DD-4 may each independently have a structure according to one of the display devices DD, DD-a, DD-TD, DD-b, and DD-c as described with reference to Figure 1 , Figure 2 and Figures 7 to 10 .

[0588] Figure 11 illustrates the vehicle AM, but this is only an example, and the first to fourth display devices DD-1, DD-2, DD-3, and DD-4 may be provided in various vehicles (such as, a bicycle, a motorcycle, a train, a ship, or an airplane). In an embodiment, at least one of the first to fourth display devices DD-1, DD-2, DD-3, and DD-4 having a structure according to one of the display devices DD, DD-TD, DD-a, DD-b, and DD-c may be included in a personal computer, a laptop computer, a personal digital terminal, a game console, a portable electronic device, a television, a monitor, a billboard, or the like. However, these are only provided as examples, and the display device may be included in other electronic devices.

[0589] At least one of the first to fourth display devices DD-1, DD-2, DD-3, and DD-4 may each independently include a light-emitting element ED according to an embodiment as described in any one of Figures 3 to 6 .

[0590] The light-emitting element ED may include: a first emission layer EML1 including the compound of (1-1) as described above (see Figure 7 ) and a second emission layer EML2 including the compound of (2-1) as described above (see Figure 7)。At least one of the first to fourth display devices DD-1, DD-2, DD-3, and DD-4 may each independently include: a light-emitting element ED including a first emission layer EML1 (see Figure 7 ) and a second emission layer EML2 (see Figure 7 ), thereby exhibiting an improved display service life.

[0591] Reference Figure 11 , the vehicle AM may include a steering wheel HA and a gear shifter GR for operating the vehicle AM. The vehicle AM may include a front window GL arranged to face the driver.

[0592] The first display device DD-1 may be arranged in a first area overlapping the steering wheel HA. For example, the first display device DD-1 may be a digital instrument panel that displays first information of the vehicle AM. The first information may include a first scale indicating the driving speed of the vehicle AM, a second scale indicating the engine speed (e.g., revolutions per minute (RPM)), an image representing a fuel gauge, etc. The first scale and the second scale may each be represented by a digital image.

[0593] The second display device DD-2 may be arranged in a second area of the driver's seat overlapping the front window GL. The driver's seat may be the seat where the steering wheel HA is arranged. For example, the second display device DD-2 may be a head-up display (HUD) that shows second information of the vehicle AM. The second display device DD-2 may be optically transparent. The second information may include a numerical value indicating the driving speed and may further include information such as the current time. Although not shown in the drawings, in an embodiment, the second information of the second display device DD-2 may be displayed by projecting it on the front window GL.

[0594] The third display device DD-3 may be arranged in a third area adjacent to the gear shifter GR. For example, the third display device DD-3 may be arranged between the driver's seat and the passenger seat and may be a center information display (CID) of the vehicle AM for displaying third information. The passenger seat may be a seat spaced apart from the driver's seat, and the gear shifter GR may be arranged between the driver's seat and the passenger seat. The third information may include information about traffic (e.g., navigation information), about the music or radio being played, about the video (or image) being displayed, about the internal temperature of the vehicle AM, etc.

[0595] The fourth display device DD-4 may be arranged in a fourth area spaced apart from the steering wheel HA and the gear shifter GR and adjacent to one side of the vehicle AM. For example, the fourth display device DD-4 may be a digital side mirror that displays fourth information. The fourth display device DD-4 may display an image of the outside of the vehicle AM captured by a camera module CM arranged outside the vehicle AM. The fourth information may include an external image of the vehicle AM.

[0596] The first to fourth information described above is provided only as an example, and the first to fourth display devices DD-1, DD-2, DD-3, and DD-4 may further display information about the inside and outside of the vehicle AM. The first to fourth information may include different information from each other. However, the embodiments are not limited thereto, and a part of the first to fourth information may include the same information.

[0597] Hereinafter, the light-emitting element according to the embodiment will be described in detail with reference to examples and comparative examples. The examples described below are provided only to assist in understanding the present disclosure, and the scope thereof is not limited thereto.

[0598] 1. Fabrication of Light-Emitting Element

[0599] The light-emitting element was fabricated by the following method. The light-emitting element includes the compound (1-1) according to the embodiment in the first emission layer and the compound (2-1) according to the embodiment in the second emission layer. Compounds A2, A17, A21, A31, and A33, which are the compound (1-1), were used as the dopant material for the first emission layer, and compounds B4, B24, B26, B37, and B38, which are the compound (2-1), were used as the dopant material for the second emission layer to fabricate the light-emitting elements of Examples 1 to 15 described below. Comparative Examples 1 to 4 do not include a second emission layer in the structure of the light-emitting element. Comparative Examples 5 to 7 correspond to light-emitting elements that use other materials instead of the compound (2-1) as the dopant material for the second emission layer. Comparative Example 8 corresponds to a light-emitting element that does not include the compound (1-1) as the dopant material for the first emission layer, and Comparative Examples 9 and 10 correspond to light-emitting elements that do not include the compound (1-1) as the dopant material for the first emission layer and do not include the compound (2-1) as the dopant material for the second emission layer.

[0600] (1) Synthesis of Compound (1-1)

[0601] The synthesis method of the compound (1-1) according to the embodiment will be described in detail by explaining the synthesis methods of compounds A2, A17, A21, A31, and A33, which are the compound (1-1). In the following description, the synthesis method of the compound (1-1) is provided only as an example, and the synthesis method of the compound (1-1) is not limited to the following examples.

[0602] 1) Synthesis of Compound A2

[0603] (Synthesis of Intermediate Compound A2-a)

[0604]

[0605] In an argon atmosphere, 5-(tert-butyl)-N1,N3-bis(5'-(tert-butyl)-[1,1':3',1"-terphenyl]-2'-yl)benzene-1,3-diamine (10 g, 13.5 mmol), 1-chloro-3-iodobenzene-2,4,5,6-d4 (6.5 g, 27 mmol), Pd2dba3 (1.6 g, 1.9 mmol), tri-tert-butylphosphine (P(t-Bu)3, 1.6 mL, 3.8 mmol) and sodium tert-butoxide (Na2O3) were added to a 2 L flask. tBuO, 11.5g, 120mmol) and dissolved in 300mL of o-xylene, and the reaction solution was stirred for about 2 hours at about 140°C. After cooling, the reaction solution was extracted by adding water (1L) and ethyl acetate (300mL) to collect the organic layer, and the organic layer was dried and filtered with MgSO4. In the filtrate, the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH2Cl2 and hexane as eluents to obtain intermediate compound A2-a (white solid, 9.2g, yield: 70%).

[0606] ESI-LCMS: [M] + :C 66 H 54 D8Cl2N2, 960.4814.

[0607] (Synthesis of Intermediate Compound A2-b)

[0608]

[0609] In an argon atmosphere, intermediate compound A2-a (9 g, 9.3 mmol) was added to a 1L flask and dissolved in 100 mL of o-dichlorobenzene, and BBr (1.5 equivalents) was added thereto. The reaction solution was stirred for about 12 hours at about 140 ° C. After the reaction solution was cooled, the reaction was terminated by adding triethylamine, and the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH2Cl2 and hexane as eluents to obtain intermediate compound A2-b (yellow solid, 2.3 g, yield: 25%).

[0610] ESI-LCMS: [M] + :C 66 H 53 D6BCl2N2, 966.4205.

[0611] (Synthesis of Compound A2)

[0612]

[0613] In an argon atmosphere, intermediate compound A2-b (2 g, 2 mmol), 9H-carbazole-1,2,3,4,5,6,7,8-d8 (0.72 g, 4 mmol), Pd2dba3 (0.06 g, 0.12 mmol), tri-tert-butylphosphine (0.06 mL, 0.24 mmol) and sodium tert-butoxide (0.5 g, 5.1 mmol) were added to a 1 L flask and dissolved in 100 mL of o-xylene, and the reaction solution was stirred at about 140 ° C for about 12 hours. After cooling, the reaction solution was extracted by adding water (1 L) and ethyl acetate (300 mL) to collect the organic layer, and the organic layer was dried and filtered with MgSO4. In the filtrate, the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH2Cl2 and hexane as eluents to obtain compound A2 (yellow solid, 2 g, yield: 80%).

[0614] ESI-LCMS: [M] + :C 90 H 53 D 22 BN4, 1244.7715.

[0615] 2) Synthesis of Compound A17

[0616] (Synthesis of Intermediate Compound A17-a)

[0617]

[0618] In an argon atmosphere, N1,N3-bis(5'-(tert-butyl)-[1,1':3',1"-terphenyl]-2'-yl)-5-(dibenzo[b,d]furan-2-yl)benzene-4,6-d2-1,3-diamine (10 g, 12 mmol), 1-chloro-3-iodobenzene-2,4,5,6-d4 (6.5 g, 27 mmol), Pd2dba3 (1.6 g, 1.9 mmol), tri-tert-butylphosphine (1.6 mL, 3.8 mmol) and sodium tert-butoxide (11.5 g, 120 mmol) were added to a 2 L flask. mmol) and dissolved in 300mL of o-xylene, and the reaction solution was stirred for about 2 hours at about 140°C. After cooling, the reaction solution was extracted by adding water (1L) and ethyl acetate (300mL) to collect the organic layer, and the organic layer was dried and filtered with MgSO4. In the filtrate, the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH2Cl2 and hexane as eluents to obtain intermediate compound A17-a (white solid, 9.1g, yield: 72%).

[0619] ESI-LCMS: [M] + :C 74 H 50 D 10 Cl2N2O, 1072.4743.

[0620] (Synthesis of Intermediate Compound A17-b)

[0621]

[0622] In an argon atmosphere, intermediate compound A17-a (9 g, 8.4 mmol) was added to a 1L flask and dissolved in 100 mL of o-dichlorobenzene, and BBr (1.5 equivalents) was added thereto. The reaction solution was stirred for about 12 hours at about 140 ° C. After the reaction solution was cooled, the reaction was terminated by adding triethylamine, and the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH2Cl2 and hexane as eluents to obtain intermediate compound A17-b (yellow solid, 2.9 g, yield: 32%).

[0623] ESI-LCMS: [M] + :C 74 H 49 D8BCl2N2O, 1078.4417.

[0624] (Synthesis of Compound A17)

[0625]

[0626] In an argon atmosphere, intermediate compound A17-b (2 g, 1.9 mmol), 9H-carbazole-1,2,3,4,5,6,7,8-d8 (0.72 g, 4 mmol), Pd2dba3 (0.06 g, 0.12 mmol), tri-tert-butylphosphine (0.06 mL, 0.24 mmol) and sodium tert-butoxide (0.5 g, 5.1 mmol) were added to a 1 L flask and dissolved in 100 mL of o-xylene, and the reaction solution was stirred at about 140 ° C for about 12 hours. After cooling, the reaction solution was extracted by adding water (1 L) and ethyl acetate (300 mL) to collect the organic layer, and the organic layer was dried and filtered with MgSO4. In the filtrate, the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH2Cl2 and hexane as eluents to obtain compound A17 (yellow solid, 1.7 g, yield: 68%).

[0627] ESI-LCMS: [M] + :C 98 H49 D 24 BN4O, 1356.7473.

[0628] 3) Synthesis of Compound A21

[0629] (Synthesis of Intermediate Compound A21-a)

[0630]

[0631] In an argon atmosphere, N1,N3-bis(5'-(tert-butyl)-[1,1':3',1"-terphenyl]-2'-yl)-5-(tert-butyl)benzene-4,6-d2-1,3-diamine (10 g, 12 mmol), 4-iodo-1,1'-biphenyl-2,2',3,3',4',5,5',6,6'-d9 (3.5 g, 12 mmol), Pd2dba3 (1.6 g, 1.9 mmol), tri-tert-butylphosphine (1.6 mL, 3.8 mmol) and sodium tert-butoxide (11.5 g, 4 mmol) were added to a 2 L flask. g, 120mmol) and dissolved in 300mL of o-xylene, and the reaction solution was stirred for about 2 hours at about 140°C. After cooling, the reaction solution was extracted by adding water (1L) and ethyl acetate (300mL) to collect the organic layer, and the organic layer was dried and filtered with MgSO4. In the filtrate, the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH2Cl2 and hexane as eluents to obtain intermediate compound A21-a (white solid, 6g, yield: 56%).

[0632] ESI-LCMS: [M] + :C 66 H 55 D9N2,894.3165.

[0633] (Synthesis of Intermediate Compound A21-b)

[0634]

[0635] In an argon atmosphere, intermediate compound A21-a (6 g, 6.7 mmol), 1-chloro-3-iodobenzene-2,4,5,6-d4 (1.7 g, 6.7 mmol), Pd2dba3 (1.6 g, 1.9 mmol), tri-tert-butylphosphine (1.6 mL, 3.8 mmol) and sodium tert-butoxide (11.5 g, 120 mmol) were added to a 2L flask and dissolved in 300 mL of o-xylene, and the reaction solution was stirred for about 2 hours at about 140 ° C. After cooling, the reaction solution was extracted by adding water (1 L) and ethyl acetate (300 mL) to collect the organic layer, and the organic layer was dried and filtered with MgSO4. In the filtrate, the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH2Cl2 and hexane as eluents to obtain intermediate compound A21-b (white solid, 4.6 g, yield: 68%).

[0636] ESI-LCMS: [M] + :C 72 H 54 D 13 ClN2, 1008.8756.

[0637] (Synthesis of Intermediate Compound A21-c)

[0638]

[0639] In an argon atmosphere, intermediate compound A21-b (4.6 g, 4.5 mmol) was added to a 1L flask and dissolved in 100 mL of o-dichlorobenzene, and BBr (1.5 equivalents) was added thereto. The reaction solution was stirred for about 12 hours at about 140 ° C. After the reaction solution was cooled, the reaction was terminated by adding triethylamine, and the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH2Cl2 and hexane as eluents to obtain intermediate compound A21-c (yellow solid, 1.2 g, yield: 26%).

[0640] ESI-LCMS: [M] + :C 72 H 53 D 11 BClN2, 1014.6531.

[0641] (Synthesis of Compound A21)

[0642]

[0643] In an argon atmosphere, intermediate compound A21-c (1.2 g, 1.2 mmol), 9H-carbazole-1,2,3,4,5,6,7,8-d8 (0.22 g, 1.2 mmol), Pd2dba3 (0.06 g, 0.12 mmol), tri-tert-butylphosphine (0.06 mL, 0.24 mmol) and sodium tert-butoxide (0.5 g, 5.1 mmol) were added to a 1 L flask and dissolved in 100 mL of o-xylene, and the reaction solution was stirred at about 140 ° C for about 12 hours. After cooling, the reaction solution was extracted by adding water (1 L) and ethyl acetate (300 mL) to collect the organic layer, and the organic layer was dried and filtered with MgSO4. In the filtrate, the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH2Cl2 and hexane as eluents to obtain compound A21 (yellow solid, 1 g, yield: 75%).

[0644] ESI-LCMS: [M] + :C 84 H 53 D 19 BN3, 1152.7002.

[0645] 4) Synthesis of Compound A31

[0646] (Synthesis of Intermediate Compound A31-a)

[0647]

[0648] In an argon atmosphere, N1,N3-bis(4-(tert-butyl)-4″-(tert-butyl)-[1,1′:3′,1″-terphenyl]-2′-yl)-5-(tert-butyl)benzene-1,3-diamine (10 g, 12 mmol), 1-chloro-3-iodobenzene-2,4,5,6-d4 (3.5 g, 12 mmol), Pd2dba3 (1.6 g, 1.9 mmol), tri-tert-butylphosphine (1.6 mL, 3.8 mmol) and sodium tert-butoxide (11.5 g, 120 mmol) were added to a 2 L flask and dissolved in 300 mL of o-xylene, and the reaction solution was stirred at about 140° C. for about 2 hours. After cooling, the reaction solution was extracted by adding water (1 L) and ethyl acetate (300 mL) to collect the organic layer, and the organic layer was dried over MgSO4 and filtered. In the filtrate, the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH 2 Cl 2 and hexane as eluents to obtain Intermediate Compound A31-a (white solid, 8.8 g, yield: 69%).

[0649] ESI-LCMS: [M] + :C74 H 70 D8Cl2N2, 1072.6027.

[0650] (Synthesis of Intermediate Compound A31-b)

[0651]

[0652] In an argon atmosphere, intermediate compound A31-a (8.8 g, 8.2 mmol) was added to a 1L flask and dissolved in 100 mL of o-dichlorobenzene, and BBr (1.5 equivalents) was added thereto. The reaction solution was stirred for about 12 hours at about 140 ° C. After the reaction solution was cooled, the reaction was terminated by adding triethylamine, and the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH2Cl2 and hexane as eluents to obtain intermediate compound A31-b (yellow solid, 2.2 g, yield: 25%).

[0653] ESI-LCMS: [M] + :C 74 H 69 D6BCl2N2, 1087.5812.

[0654] (Synthesis of Compound A31)

[0655]

[0656] In an argon atmosphere, intermediate compound A31-b (2.2 g, 2 mmol), 9H-carbazole-1,2,3,4,5,6,7,8-d8 (0.72 g, 4 mmol), Pd2dba3 (0.06 g, 0.12 mmol), tri-tert-butylphosphine (0.06 mL, 0.24 mmol) and sodium tert-butoxide (0.5 g, 5.1 mmol) were added to a 1 L flask and dissolved in 100 mL of o-xylene, and the reaction solution was stirred at about 140 ° C for about 12 hours. After cooling, the reaction solution was extracted by adding water (1 L) and ethyl acetate (300 mL) to collect the organic layer, and the organic layer was dried and filtered with MgSO4. In the filtrate, the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH2Cl2 and hexane as eluents to obtain compound A31 (yellow solid, 2 g, yield: 77%).

[0657] ESI-LCMS: [M] + :C 98 H 69 D 22 BN4, 1356.8783.

[0658] 5) Synthesis of Compound A33

[0659] (Synthesis of Intermediate Compound A33-a)

[0660]

[0661] In an argon atmosphere, 5-(tert-butyl)-N1,N3-bis(5'-(tert-butyl)-[1,1':3',1"-terphenyl]-2'-yl)benzene-1,3-diamine (10 g, 13.6 mmol), 1-chloro-3-iodobenzene-2,4,5,6-d4 (3.2 g, 13.6 mmol), Pd2dba3 (1.6 g, 1.9 mmol), tri-tert-butylphosphine (1.6 mL, 3.8 mmol) and sodium tert-butoxide (11.5 g, 120 mmol) were added to a 2 L flask and Dissolved in 300mL of o-xylene, and the reaction solution was stirred for about 2 hours at about 140 ℃.After cooling, the reaction solution was extracted by adding water (1L) and ethyl acetate (300mL) to collect the organic layer, and the organic layer was dried and filtered with MgSO4. In the filtrate, the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH2Cl2 and hexane as eluent, to obtain intermediate compound A33-a (white solid, 6.7g, yield: 58%).

[0662] ESI-LCMS: [M] + :C 60 H 55 D4ClN2, 846.4655.

[0663] (Synthesis of Intermediate Compound A33-b)

[0664]

[0665] In an argon atmosphere, intermediate compound A33-a (6.7 g, 7.9 mmol), 4,4″-((5-iodo-1,3-phenylene-4,6-d2)bis(oxy))bis((1,1′-biphenyl-2,3,5,6-d4)) (4.4 g, 7.9 mmol), Pd2dba3 (1.6 g, 1.9 mmol), tri-tert-butylphosphine (1.6 mL, 3.8 mmol) and sodium tert-butoxide (11.5 g, 120 mmol) were added to a 2 L flask and dissolved in 30 0mL of o-xylene, and the reaction solution was stirred for about 2 hours at about 140 ℃.After cooling, the reaction solution was extracted with collected organic layer by adding water (1L) and ethyl acetate (300mL), and the organic layer was dried and filtered with MgSO4. In the filtrate, the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH2Cl2 and hexane as eluent, to obtain intermediate compound A33-b (white solid, 7.2g, yield: 72%).

[0666] ESI-LCMS: [M] + :C 90 H 65 D 14 ClN2O2, 1268.6746.

[0667] (Synthesis of Intermediate Compound A33-c)

[0668]

[0669] In an argon atmosphere, intermediate compound A33-b (7.2 g, 5.6 mmol) was added to a 1L flask and dissolved in 100 mL of o-dichlorobenzene, and BBr (1.5 equivalents) was added thereto. The reaction solution was stirred for about 12 hours at about 140 ° C. After the reaction solution was cooled, the reaction was terminated by adding triethylamine, and the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH2Cl2 and hexane as eluents to obtain intermediate compound A33-c (yellow solid, 2.6 g, yield: 36%).

[0670] ESI-LCMS: [M] + :C 90 H 63 D 10 B2ClN2O2, 1280.6267.

[0671] (Synthesis of Compound A33)

[0672]

[0673] In an argon atmosphere, intermediate compound A33-c (2 g, 1.5 mmol), 9H-carbazole-1,2,3,4,5,6,7,8-d8 (0.27 g, 1.5 mmol), Pd2dba3 (0.06 g, 0.12 mmol), tri-tert-butylphosphine (0.06 mL, 0.24 mmol) and sodium tert-butoxide (0.5 g, 5.1 mmol) were added to a 1 L flask and dissolved in 100 mL of o-xylene, and the reaction solution was stirred at about 140 ° C for about 12 hours. After cooling, the reaction solution was extracted by adding water (1 L) and ethyl acetate (300 mL) to collect the organic layer, and the organic layer was dried and filtered with MgSO4. In the filtrate, the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH2Cl2 and hexane as eluents to obtain compound A33 (yellow solid, 1.6 g, yield: 77%).

[0674] ESI-LCMS: [M] + :C 102 H 63 D 18 B2N3O2, 1419.7611.

[0675] (2) Synthesis of Compound (2-1)

[0676] The synthesis method of the compound (2-1) according to the embodiment will be described in detail by explaining the synthesis methods of compound B4, compound B24, compound B26, compound B37 and compound B38 as the compound (2-1). In the following description, the synthesis method of the compound (2-1) is provided only as an example, and the synthesis method of the compound (2-1) is not limited to the following examples.

[0677] 1) Synthesis of compound B4

[0678] (Synthesis of Intermediate Compound B4-a)

[0679]

[0680] In an argon atmosphere, 5-(tert-butyl)-N1,N3-bis(5'-(tert-butyl)-[1,1':3',1"-terphenyl]-2'-yl)benzene-1,3-diamine (10 g, 13.5 mmol), 1-chloro-3-iodobenzene-2,4,5,6-d4 (3.3 g, 13.5 mmol), Pd2dba3 (1.6 g, 1.9 mmol), tri-tert-butylphosphine (1.6 mL, 3.8 mmol) and sodium tert-butoxide (11.5 g, 120 mmol) were added to a 2 L flask and stirred for 2 h. And be dissolved in 300mL of o-xylene, and the reaction solution is stirred for about 2 hours at about 140 ℃.After cooling, extract the reaction solution to collect organic layer by adding water (1L) and ethyl acetate (300mL), and by organic layer MgSO4 dry and filter.In filtrate, remove solvent under reduced pressure to obtain solid.The solid thus obtained is purified and separated by silica gel column chromatography using CH2Cl2 and hexane as eluent, to obtain intermediate compound B4-a (white solid, 8.3g, yield: 73%).

[0681] ESI-LCMS: [M] + :C 60 H 55 D4ClN2, 846.4606.

[0682] (Synthesis of Intermediate Compound B4-b)

[0683]

[0684] In an argon atmosphere, intermediate compound B4-a (8 g, 9.5 mmol), 9-(3-bromobenzo[b]thiophene-6-yl-4,5,7-d3)-9H-carbazole-1,2,3,4,5,6,7,8-d8 (3.7 g, 9.5 mmol), Pd2dba3 (1.6 g, 1.9 mmol), tri-tert-butylphosphine (1.6 mL, 3.8 mmol) and sodium tert-butoxide (11.5 g, 120 mmol) were added to a 2L flask and dissolved in 300 mL of o-xylene, and the reaction solution was stirred at about 140° C. for about 2 hours. After cooling, the reaction solution was extracted by adding water (1 L) and ethyl acetate (300 mL) to collect the organic layer, and the organic layer was dried with MgSO4 and filtered. In the filtrate, the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH 2 Cl 2 and hexane as eluents to obtain Intermediate Compound B4-b (white solid, 8.4 g, yield: 77%).

[0685] ESI-LCMS: [M] + :C 80 H 56 D14 ClN3S, 1153.5759.

[0686] (Synthesis of Intermediate Compound B4-c)

[0687]

[0688] In an argon atmosphere, intermediate compound B4-b (8.4 g, 7.3 mmol) was added to a 1L flask and dissolved in 100 mL of o-dichlorobenzene, and BBr (1.5 equivalents) was added thereto. The reaction solution was stirred for about 12 hours at about 140 ° C. After the reaction solution was cooled, the reaction was terminated by adding triethylamine, and the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH2Cl2 and hexane as eluents to obtain intermediate compound B4-c (yellow solid, 2 g, yield: 24%).

[0689] ESI-LCMS: [M] + :C 80 H 53 D 14 BClN3S, 1161.5117.

[0690] (Synthesis of Compound B4)

[0691]

[0692] In an argon atmosphere, intermediate compound B4-c (2 g, 1.2 mmol), 3-(pyrene-1-yl)-9H-carbazole-1,2,4,5,6,7,8-d7 (0.64 g, 1.4 mmol), Pd2dba3 (0.06 g, 0.12 mmol), tri-tert-butylphosphine (0.06 mL, 0.24 mmol) and sodium tert-butoxide (0.5 g, 5.1 mmol) were added to a 1 L flask and dissolved in 100 mL of o-xylene, and the reaction solution was stirred at about 140 ° C for about 12 hours. After cooling, the reaction solution was extracted by adding water (1 L) and ethyl acetate (300 mL) to collect the organic layer, and the organic layer was dried with MgSO4 and filtered. In the filtrate, the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH 2 Cl 2 and hexane as eluents to obtain Compound B4 (yellow solid, 1.93 g, yield: 76%).

[0693] ESI-LCMS: [M] + :C 108 H 62 D 21 BN4S, 1499.7577.

[0694] 2) Synthesis of compound B24

[0695] (Synthesis of Intermediate Compound B24-a)

[0696]

[0697] In an argon atmosphere, 5-(tert-butyl)-N1,N3-bis(5'-(tert-butyl)-[1,1':3',1"-terphenyl]-2'-yl)benzene-1,3-diamine (10 g, 13.6 mmol), 1-chloro-3-iodobenzene-2,4,5,6-d4 (3.2 g, 13.6 mmol), Pd2dba3 (1.6 g, 1.9 mmol), tri-tert-butylphosphine (1.6 mL, 3.8 mmol) and sodium tert-butoxide (11.5 g, 120 mmol) were added to a 2 L flask and Dissolved in 300mL of o-xylene, and the reaction solution was stirred for about 2 hours at about 140 ℃. After cooling, the reaction solution was extracted by adding water (1L) and ethyl acetate (300mL) to collect the organic layer, and the organic layer was dried and filtered with MgSO4. In the filtrate, the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH2Cl2 and hexane as eluents, to obtain intermediate compound B24-a (white solid, 6.7g, yield: 58%).

[0698] ESI-LCMS: [M] + :C 60 H 55 D4ClN2, 846.4655.

[0699] (Synthesis of Intermediate Compound B24-b)

[0700]

[0701] In an argon atmosphere, intermediate compound B24-a (6.7 g, 7.9 mmol), 3-iodo-7-(2-(pyrene-1-yl)phenyl)benzo[b]thiophene (4.2 g, 7.9 mmol), Pd2dba3 (1.6 g, 1.9 mmol), tri-tert-butylphosphine (1.6 mL, 3.8 mmol) and sodium tert-butoxide (11.5 g, 120 mmol) were added to a 2 L flask and dissolved in 300 mL of o-xylene, and the reaction solution was stirred at about 140 ° C for about 2 hours. After cooling, the reaction solution was extracted by adding water (1 L) and ethyl acetate (300 mL) to collect the organic layer, and the organic layer was dried with MgSO4 and filtered. In the filtrate, the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH 2 Cl 2 and hexane as eluents to obtain an intermediate compound B24-b (white solid, 7.4 g, yield: 75%).

[0702] ESI-LCMS: [M] + :C 90 H 72 D3ClN2S, 1253.5546.

[0703] (Synthesis of Intermediate Compound B24-c)

[0704]

[0705] In an argon atmosphere, intermediate compound B24-b (7.4 g, 5.9 mmol) was added to a 1L flask and dissolved in 100 mL of o-dichlorobenzene, and BBr (1.5 equivalents) was added thereto. The reaction solution was stirred for about 12 hours at about 140 ° C. After the reaction solution was cooled, the reaction was terminated by adding triethylamine, and the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH2Cl2 and hexane as eluents to obtain intermediate compound B24-c (yellow solid, 2.2 g, yield: 29%).

[0706] ESI-LCMS: [M] + :C 90 H 69 D3BClN2S, 1261.5434.

[0707] (Synthesis of Compound B24)

[0708]

[0709] In an argon atmosphere, intermediate compound B24-c (2 g, 1.6 mmol), 9H-carbazole-1,2,3,4,5,6,7,8-d8 (0.29 g, 1.6 mmol), Pd2dba3 (0.06 g, 0.12 mmol), tri-tert-butylphosphine (0.06 mL, 0.24 mmol) and sodium tert-butoxide (0.5 g, 5.1 mmol) were added to a 1 L flask and dissolved in 100 mL of o-xylene, and the reaction solution was stirred at about 140 ° C for about 12 hours. After cooling, the reaction solution was extracted by adding water (1 L) and ethyl acetate (300 mL) to collect the organic layer, and the organic layer was dried and filtered with MgSO4. In the filtrate, the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH2Cl2 and hexane as eluents to obtain compound B24 (yellow solid, 1.7 g, yield: 77%).

[0710] ESI-LCMS: [M] + :C 102 H 77 D3BN3S, 1392.6461.

[0711] 3) Synthesis of Compound B26

[0712] (Synthesis of Intermediate Compound B26-a)

[0713]

[0714] In an argon atmosphere, N-(3-bromo-5-(tert-butyl)phenyl)-5-(tert-butyl)-N-(3-chlorophenyl-2,4,5-d3)-3'-(10-phenylanthracen-9-yl)-[1,1'-biphenyl]-2-amine (10 g, 12 mmol), 5'-(tert-butyl)-[1,1':3',1"-terphenyl]-2'-amine (3.75 g, 13.6 mmol), Pd2dba3 (1.6 g, 1.9 mmol), tri-tert-butylphosphine (1.6 mL, 3.8 mmol) and sodium tert-butoxide (1 mL) were added to a 2 L flask. 1.5g, 120mmol) and dissolved in 300mL of o-xylene, and the reaction solution was stirred for about 2 hours at about 140°C. After cooling, the reaction solution was extracted by adding water (1L) and ethyl acetate (300mL) to collect the organic layer, and the organic layer was dried and filtered with MgSO4. In the filtrate, the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH2Cl2 and hexane as eluents to obtain intermediate compound B26-a (white solid, 8.6g, yield: 76%).

[0715] ESI-LCMS: [M]+ :C 74 H 64 D3ClN2, 1021.5231.

[0716] (Synthesis of Intermediate Compound B26-b)

[0717]

[0718] In an argon atmosphere, intermediate compound B26-a (8.6 g, 8.4 mmol), 6- (tert-butyl) -3- iodobenzo [b] thiophene (2.7 g, 8.4 mmol), Pd2dba3 (1.6 g, 1.9 mmol), tri-tert-butylphosphine (1.6 mL, 3.8 mmol) and sodium tert-butoxide (11.5 g, 120 mmol) were added to a 2 L flask and dissolved in 300 mL of o-xylene, and the reaction solution was stirred for about 2 hours at about 140 ° C. After cooling, the reaction solution was extracted by adding water (1 L) and ethyl acetate (300 mL) to collect the organic layer, and the organic layer was dried and filtered with MgSO4. In the filtrate, the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH2Cl2 and hexane as eluents to obtain intermediate compound B26-b (white solid, 7.8 g, yield: 77%).

[0719] ESI-LCMS: [M] + :C 86 H 76 D3ClN2S, 1209.5851.

[0720] (Synthesis of Intermediate Compound B26-c)

[0721]

[0722] In an argon atmosphere, intermediate compound B26-b (7.8 g, 5.9 mmol) was added to a 1L flask and dissolved in 100 mL of o-dichlorobenzene, and BBr (1.5 equivalents) was added thereto. The reaction solution was stirred for about 12 hours at about 140 ° C. After the reaction solution was cooled, the reaction was terminated by adding triethylamine, and the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH2Cl2 and hexane as eluents to obtain intermediate compound B26-c (yellow solid, 1.9 g, yield: 24%).

[0723] ESI-LCMS: [M] + :C 86 H 73 D3BClN2S, 1217.5711.

[0724] (Synthesis of Compound B26)

[0725]

[0726] In an argon atmosphere, intermediate compound B26-c (1.9 g, 1.6 mmol), 9H-carbazole (0.29 g, 1.6 mmol), Pd2dba3 (0.06 g, 0.12 mmol), tri-tert-butylphosphine (0.06 mL, 0.24 mmol) and sodium tert-butoxide (0.5 g, 5.1 mmol) were added to a 1 L flask and dissolved in 100 mL of o-xylene, and the reaction solution was stirred for about 12 hours at about 140 ° C. After cooling, the reaction solution was extracted by adding water (1 L) and ethyl acetate (300 mL) to collect the organic layer, and the organic layer was dried and filtered with MgSO4. In the filtrate, the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH2Cl2 and hexane as eluents to obtain compound B26 (yellow solid, 1.6 g, yield: 74%).

[0727] ESI-LCMS: [M] + :C 98 H 81 D3BN3S, 1348.6717.

[0728] 4) Synthesis of Compound B37

[0729] (Synthesis of Intermediate Compound B37-a)

[0730]

[0731] In an argon atmosphere, intermediate compound B24-a (10 g, 12 mmol), 9- (3-iodobenzo [b] thiophene-6-yl) -9H-carbazole (5 g, 12 mmol), Pd2dba3 (1.6 g, 1.9 mmol), tri-tert-butylphosphine (1.6 mL, 3.8 mmol) and sodium tert-butoxide (11.5 g, 120 mmol) were added to a 2 L flask and dissolved in 300 mL of o-xylene, and the reaction solution was stirred at about 140 ° C for about 2 hours. After cooling, the reaction solution was extracted by adding water (1 L) and ethyl acetate (300 mL) to collect the organic layer, and the organic layer was dried and filtered with MgSO4. In the filtrate, the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH2Cl2 and hexane as eluents to obtain intermediate compound B37-a (white solid, 9.7 g, yield: 79%).

[0732] ESI-LCMS: [M]+ :C 80 H 66 D4ClN3S, 1143.5262.

[0733] (Synthesis of Intermediate Compound B37-b)

[0734]

[0735] In an argon atmosphere, intermediate compound B37-a (9.7 g, 8.5 mmol) was added to a 1L flask and dissolved in 100 mL of o-dichlorobenzene, and BBr (1.5 equivalents) was added thereto. The reaction solution was stirred for about 12 hours at about 140 ° C. After the reaction solution was cooled, the reaction was terminated by adding triethylamine, and the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH2Cl2 and hexane as eluents to obtain intermediate compound B37-b (yellow solid, 1.9 g, yield: 18%).

[0736] ESI-LCMS: [M] + :C 80 H 64 D3BClN3S, 1150.5002.

[0737] (Synthesis of Compound B37)

[0738]

[0739] In an argon atmosphere, intermediate compound B37-b (1.9 g, 1.6 mmol), 9-(9H-carbazole-3-yl) acridine (0.57 g, 1.6 mmol), Pd2dba3 (0.06 g, 0.12 mmol), tri-tert-butylphosphine (0.06 mL, 0.24 mmol) and sodium tert-butoxide (0.5 g, 5.1 mmol) were added to a 1 L flask and dissolved in 100 mL of o-xylene, and the reaction solution was stirred for about 12 hours at about 140 ° C. After cooling, the reaction solution was extracted by adding water (1 L) and ethyl acetate (300 mL) to collect the organic layer, and the organic layer was dried and filtered with MgSO4. In the filtrate, the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH2Cl2 and hexane as eluents to obtain compound B37 (yellow solid, 1.7 g, yield: 73%).

[0740] ESI-LCMS: [M] + :C 105 H 79 D3BN5S, 1458.6642.

[0741] 5) Synthesis of Compound B38

[0742] (Synthesis of Compound B38)

[0743]

[0744] In an argon atmosphere, intermediate compound B37-b (1.9 g, 1.6 mmol), 3-(acenaphthene-1-yl)-9H-carbazole (0.5 g, 1.6 mmol), Pd2dba3 (0.06 g, 0.12 mmol), tri-tert-butylphosphine (0.06 mL, 0.24 mmol) and sodium tert-butoxide (0.5 g, 5.1 mmol) were added to a 1 L flask and dissolved in 100 mL of o-xylene, and the reaction solution was stirred for about 12 hours at about 140 ° C. After cooling, the reaction solution was extracted by adding water (1 L) and ethyl acetate (300 mL) to collect the organic layer, and the organic layer was dried and filtered with MgSO4. In the filtrate, the solvent was removed under reduced pressure to obtain a solid. The solid thus obtained was purified and separated by silica gel column chromatography using CH2Cl2 and hexane as eluents to obtain compound B38 (yellow solid, 1.7 g, yield: 74%).

[0745] ESI-LCMS: [M] + :C 104 H 78 D3BN4S, 1431.6539.

[0746] The (1-1) compounds synthesized in Examples 1 to 5 1 H NMR chemical shift (CDCl3) and the (2-1) compounds synthesized in Examples 1 to 5 1 H NMR chemical shifts (CDCl3) are shown in Table 1 below. With reference to the above synthetic routes and starting materials, one skilled in the art can readily identify methods for synthesizing other compounds.

[0747] Table 1

[0748]

[0749] (3) Manufacturing of light-emitting elements

[0750] In the light-emitting element of Example 1, a 15Ω / cm 2 (about ) The glass substrate of the ITO electrode (manufactured by Corning) was cut into a size of approximately 50 mm × 50 mm × 0.7 mm, ultrasonically cleaned with isopropyl alcohol and pure water for about five minutes each, irradiated with ultraviolet light for about 30 minutes, and exposed to ozone and cleaned. The glass substrate was mounted on a vacuum deposition apparatus.

[0751] NPD was deposited on the upper part of the anode to form a thick hole injection layer, and Compound H-1-19 was deposited on the upper part of the hole injection layer to form a thick hole transport layer, and CzSi was deposited on the upper part of the hole transport layer to form a thick emission assisting layer.

[0752] A host in which the first host HT59 and the second host ETH66 were mixed at a weight ratio of 1:1, a sensitizer AD-39, and Compound A2 were co-deposited at a weight ratio of 85:14:1 to form a thick first emission layer, and a third host E20 and Compound B4 were co-deposited on the upper part of the first emission layer at a weight ratio of 98:2 to form a thick second emission layer, thereby fabricating the emission layer. TSPO1 was deposited on the upper part of the emission layer to form a thick hole blocking layer. On the upper part of the hole blocking layer, TPBi was deposited to form a thick electron transport layer, and on the upper part of the electron transport layer, LiF was deposited to form a thick electron injection layer. On the electron injection layer, Al was deposited to form a thick cathode. Compound P4 was deposited on the upper part of the cathode to form a thick capping layer, thereby fabricating the light-emitting element. Each layer was formed by a vacuum deposition method.

[0753] The light-emitting element of Example 2 was fabricated in substantially the same manner as the light-emitting element of Example 1, except that the thickness of the second emission layer was different from that in Example 1. The light-emitting element of Comparative Example 1 was fabricated in substantially the same manner as the light-emitting element of Example 1, except that the structure of the emission layer was different from that in Example 1. The light-emitting elements of Comparative Examples 2 to 4 were fabricated in substantially the same manner as the light-emitting element of Example 1, except that the structure of the emission layer and the compound used to form the first emission layer were different from those in Example 1. The light-emitting elements of Comparative Examples 5 to 10 were fabricated in substantially the same manner as the light-emitting element of Example 1, except that the compounds used to form the first emission layer and / or the second emission layer were different from those in Example 1. The structures of the light-emitting elements of the examples and comparative examples, the types of compounds used for fabrication, and the thickness of the second emission layer are shown in Table 3 below.

[0754] The compounds used to fabricate the light-emitting elements of the examples and comparative examples are shown below. By subjecting commercial products to sublimation purification, the following materials are used to fabricate the light-emitting elements.

[0755] [Compound (1-1) in the example]

[0756]

[0757] [Compound (2-1) in the example]

[0758]

[0759] [Comparative example compound]

[0760]

[0761] [Compound for fabricating the light-emitting element]

[0762]

[0763] 2. Evaluation of the compound and the characteristics of the light-emitting element

[0764] (Evaluation of the compound characteristics)

[0765] The highest occupied molecular orbital (HOMO) energy levels of Compound A2, Compound A17, Compound A21, Compound A31, and Compound A33 of the (1-1) compounds of the example compounds, Compound B4, Compound B24, Compound B26, Compound B37, and Compound B38 of the (2-1) compounds of the example compounds, and Comparative Example Compounds C1 to C3 of the comparative example compounds were measured using the Smart Manager software of the SP2 electrochemical workstation equipment from ZIVE LAB. In the case where a xenon light source and a monochromator are installed on the fluoromax+ spectrometer equipment from HORIBA, the lowest excited singlet state energy level (S1), the lowest excited triplet state energy level (T1), FWQM (full width at quarter maximum), and the maximum emission wavelength (λ max)。The structure and corresponding energy of the second stable triplet excited state are calculated by unrestricted density functional theory (UDFT) calculations to determine the second excited triplet energy level (T2), and the commercial program Gaussian09 is used, and UDFT calculations are performed using the 6-311g(d,p) basis function and the B3LYP exchange-correlation function. When a deuterium / tungsten-halogen light source and a silicon photodiode are installed on a UV-1800 UV / Visible Scanning Spectrophotometer instrument (SHIMADZU), the maximum absorption wavelength (λ abs ) is measured using Labsolution UV-Vis software. The Stokes shift is calculated by the difference between the maximum absorption wavelength (λ abs ) and the maximum emission wavelength (λ max ). The results of the measured values and calculated values are listed in Table 2.

[0766] Table 2

[0767]

[0768] (Evaluation of Light-Emitting Element Characteristics)

[0769] The luminous efficiency and element service life of light-emitting elements fabricated using the (1-1) compounds A2, A17, A21, A31, and A33 of the example compounds, the (2-1) compounds B4, B24, B26, B37, and B38 of the example compounds, and comparative compounds C1 to C3 as described above were evaluated. The evaluation results of the light-emitting elements of Examples 1 to 15 and Comparative Examples 1 to 10 are listed in Table 3. To evaluate the characteristics of the light-emitting elements fabricated in Examples 1 to 15 and Comparative Examples 1 to 10 above, the driving voltage (V), luminous efficiency (Cd / A / y), and color purity (CIEy) at a current density of 1,000 cd / m 2 were measured using Keithley MU 236 and a luminance meter PR650, and the time required to reach 95% luminance relative to the initial luminance was measured as the service life (T95), and the relative service life was calculated based on the light-emitting element of Comparative Example 1, and the results are listed in Table 3.

[0770] Table 3

[0771]

[0772]

[0773] Referring to the results in Table 3, it can be confirmed that, compared with the light-emitting elements of the comparative examples, the light-emitting elements of the examples according to the embodiment have the characteristics of low driving voltage, excellent blue color purity and luminous efficiency, and at the same time, have relatively improved service life characteristics.

[0774] Since each of the light-emitting elements of the examples includes an emission layer having a structure in which a first emission layer and a second emission layer are stacked, a long service life can be achieved. The first emission layer included in the light-emitting element of the example includes the (1-1) compound and the second emission layer includes the (2-1) compound. The (1-1) compound may have a structure including a first fused ring nucleus in which a boron atom and two nitrogen atoms are fused, and in which triphenyl substituents are each connected to a nitrogen atom of the first fused ring nucleus. The (2-1) compound may have a structure including a second fused ring nucleus in which a boron atom, two nitrogen atoms and a heteroatom from Group VI are fused, and in which a carbazole substituent is connected to the second fused ring nucleus and a triphenyl substituent is connected to the second nitrogen atom. The lowest excited triplet energy level of the (2-1) compound may be in the range of about 1.5 eV to about 2.1 eV. In the light-emitting element according to the embodiment, the (1-1) compound and the (2-1) compound are respectively used as dopants of the delayed fluorescence light-emitting elements in the first emission layer and the second emission layer, thereby achieving excellent color purity, high luminous efficiency and long service life in a short wavelength region such as the blue light wavelength region.

[0775] Referring to the results in Table 2 and Table 3, it can be confirmed that, compared with the examples, Comparative Example 1 has a relatively deteriorated element service life. It should be understood that Comparative Example 1 includes: a first emission layer including the (1-1) compound, but does not include a second emission layer as a component of the emission layer, and thus, compared with the examples, the element service life is deteriorated.

[0776] It can be confirmed that, compared with the examples, Comparative Examples 2 to 4 have relatively deteriorated element service life and / or reduced luminous efficiency. It should be understood that Comparative Examples 2 to 4 do not include a second emission layer as a component of the emission layer, and thus, compared with the examples, the element service life is deteriorated. It should be understood that Comparative Examples 2 to 4 do not include the (1-1) compound as a material for the first emission layer, and thus, compared with the examples, the luminous efficiency is deteriorated.

[0777] It can be confirmed that Comparative Example 5 has a relatively deteriorated element service life and reduced luminous efficiency compared with the Examples. Comparative Example 5 includes: a first emission layer including the (1-1) compound, but does not include the (2-1) compound but includes Comparative Example Compound C1 as the material of the second emission layer. Different from the (2-1) compound according to the embodiment, Comparative Example Compound C1 does not include a planar skeleton structure centered on a boron atom and two nitrogen atoms. Accordingly, it should be understood that the FWQM and Stokes shift values of Comparative Example Compound C1 are relatively large, and Comparative Example 5 including Comparative Example Compound C1 in the first emission layer has a deteriorated element service life and reduced luminous efficiency compared with the Examples. Different from the (2-1) compound, Comparative Example Compound C1 has a value of the lowest excited triplet energy level (T1) greater than about 2.1 eV. Accordingly, it should be understood that Comparative Example 5 including Comparative Example Compound C1 in the first emission layer has a deteriorated element service life and reduced luminous efficiency compared with the Comparative Examples.

[0778] It can be confirmed that Comparative Examples 6 and 7 have a relatively deteriorated element service life and / or reduced luminous efficiency compared with the Examples. Comparative Examples 6 and 7 include: a first emission layer including the (1-1) compound, but does not include the (2-1) compound but includes Comparative Example Compound C2 and Comparative Example Compound C3 as the materials of the second emission layer, respectively. Comparative Example Compound C2 and Comparative Example Compound C3 partially include a planar skeleton structure centered on a boron atom and two nitrogen atoms, but do not include a terphenyl substituent. Accordingly, it should be understood that it is relatively difficult to control the Dexter energy transfer of Comparative Example Compound C2 and Comparative Example Compound C3, the HOMO energy levels are relatively high, and the element service lives of Comparative Examples 6 and 7 including Comparative Example Compound C2 and Comparative Example Compound C3 in the first emission layer, respectively, are deteriorated and the luminous efficiencies are reduced. Different from the (2-1) compound according to the embodiment, each of Comparative Example Compound C2 and Comparative Example Compound C3 has a value of the lowest excited triplet energy level (T1) greater than about 2.1 eV. Accordingly, it should be understood that Comparative Examples 6 and 7 including Comparative Example Compound C2 and Comparative Example Compound C3 in the first emission layer, respectively, have a deteriorated element service life and reduced luminous efficiency compared with the Examples.

[0779] It can be confirmed that Comparative Example 8 has a relatively deteriorated element service life and reduced luminous efficiency compared with the Examples. Comparative Example 8 includes: a second emission layer including the (2-1) compound, but does not include the (1-1) compound but includes Comparative Example Compound C2 as the material of the first emission layer. Accordingly, it should be understood that the HOMO energy level of Comparative Example Compound C2 is relatively high, and the element service life of Comparative Example 8 including Comparative Example Compound C2 in the second emission layer is deteriorated and the luminous efficiency is reduced.

[0780] It can be confirmed that, compared with the examples, Comparative Example 9 and Comparative Example 10 have relatively deteriorated element service lives and reduced luminous efficiencies. Comparative Example 9 and Comparative Example 10 do not include the (1-1) compound but include Comparative Compound C2 and Comparative Compound C3 as the materials for the first emission layer, respectively, and do not include the (2-1) compound but include Comparative Compound C2 and Comparative Compound C3 as the materials for the second emission layer, respectively. Accordingly, it should be understood that Comparative Example 9 and Comparative Example 10 do not include the (1-1) compound as the material for the first emission layer and the (2-1) compound as the material for the second emission layer, and thus the element service lives are deteriorated and the luminous efficiencies are reduced.

[0781] The light-emitting element according to the embodiment can exhibit improved element characteristics with high luminous efficiency and long service life.

[0782] The display device according to the embodiment can provide a display device with improved reliability by including the light-emitting element according to the embodiment.

[0783] Embodiments have been disclosed herein, and although terms are employed, they are used and interpreted only in a general and descriptive sense and not for purposes of limitation. In some cases, as will be apparent to those of ordinary skill in the art, features, characteristics, and / or elements described in connection with an embodiment may be used alone or in combination with features, characteristics, and / or elements described in connection with other embodiments, unless otherwise specifically indicated. Accordingly, those of ordinary skill in the art will understand that various forms and details changes can be made without departing from the spirit and scope of the present disclosure as set forth in the claims.

Claims

1. A light-emitting element, comprising: A first electrode; A first emission layer disposed on the first electrode and including a (1-1) compound represented by Formula 1; A second emission layer disposed on the first emission layer and including a (2-1) compound represented by Formula 2; And A second electrode disposed on the second emission layer, wherein The (2-1) compound has a lowest excited triplet energy level in the range of 1.5 eV to 2.1 eV: Formula 1 Wherein in Formula 1, R1 to R 11 each independently is a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a hydroxyl group, a substituted or unsubstituted oxy group, a substituted or unsubstituted thio group, a substituted or unsubstituted seleno group, a substituted or unsubstituted telluro group, a substituted or unsubstituted boron group, a substituted or unsubstituted silyl group, a substituted or unsubstituted amino 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 aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring carbon atoms, or is bonded to an adjacent group to form a ring, X1 to X6 are each independently a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a hydroxyl group, a substituted or unsubstituted oxy group, a substituted or unsubstituted thio group, a substituted or unsubstituted silyl group, a substituted or unsubstituted amino 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 aryl group having 6 to 30 ring carbon atoms or a substituted or unsubstituted heteroaryl group having 2 to 30 ring carbon atoms, or bonded to an adjacent group to form a ring, n1, n3, n4 and n6 are each independently an integer selected from 0 to 5, and n2 and n5 are each independently an integer selected from 0 to 3, Formula 2 Wherein in Formula 2, X is O, S, Se or Te, Ar is a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms or a substituted or unsubstituted heteroaryl group having 2 to 30 ring carbon atoms, R 12 to R 17 and R x1 to R x3 Each independently is a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a hydroxyl group, a substituted or unsubstituted silyl 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 2 to 30 ring carbon atoms. R y1 、R y2 and R z1 are each independently a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a hydroxyl group, a substituted or unsubstituted amino 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 aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, or are bonded to adjacent groups to form a ring. x1 and x3 are each independently an integer selected from 0 to 5, x2 is an integer selected from 0 to 3, and y1, y2 and z1 are each independently an integer selected from 0 to 4.

2. The light-emitting element according to claim 1, wherein The first emission layer emits fluorescence through thermally activated delayed fluorescence, and The second emission layer emits fluorescence through triplet-triplet annihilation.

3. The light-emitting element according to claim 1, wherein the (1-1) compound has a lowest excited triplet energy level in the range of 2.5 eV to 3.1 eV.

4. The light-emitting element according to claim 1, wherein The first emission layer includes: A first light-emitting host; And A first light-emitting dopant doped into the first light-emitting host and including the (1-1) compound, the second emission layer includes: A second light-emitting host; And A second light-emitting dopant doped into the second light-emitting host and including the (2-1) compound, and The material included in the first light-emitting host is different from the material included in the second light-emitting host.

5. The light-emitting element according to claim 1, wherein the first emission layer further includes: At least one of a (1-2) compound represented by Formula HT-1, a (1-3) compound represented by Formula ET-1 and a (1-4) compound represented by Formula D-1: Formula HT-1 Wherein in Formula HT-1, A1 to A8 are each independently N or C(R 51 ), L1 is a direct bond, 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, Y a is directly connected, C(R 52 )(R 53 ) or Si(R 54 )(R 55 ), Ar1 is a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms or a substituted or unsubstituted heteroaryl group having 2 to 30 ring carbon atoms, and R 51 to R 55 each independently represents a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a substituted or unsubstituted silyl group, a substituted or unsubstituted thio group, a substituted or unsubstituted oxy group, a substituted or unsubstituted amino group, a substituted or unsubstituted boron 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 aryl group having 6 to 60 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 60 ring-forming carbon atoms, or is bonded to an adjacent group to form a ring; Formula ET-1 wherein in Formula ET-1, at least one of X1 to X3 is each N, The remainder of X1 to X3 are each independently C(R 56 ), R 56 is a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 60 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 60 ring carbon atoms, b1 to b3 are each independently an integer selected from 0 to 10, Ar2 to Ar4 are each independently a hydrogen atom, a deuterium atom, 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 2 to 30 ring carbon atoms, and L2 to L4 are each independently a direct bond, 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; Formula D-1 wherein in Formula D-1, Q1 to Q4 are each independently C or N, C1 to C4 are each independently a substituted or unsubstituted hydrocarbon ring group having 5 to 30 ring carbon atoms or a substituted or unsubstituted heterocyclic group having 2 to 30 ring carbon atoms, L 11 to L 13 each independently is a direct bond, *-O-*, *-S-*, a substituted or unsubstituted alkylene having 1 to 20 carbon atoms, a substituted or unsubstituted arylene having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroarylene having 2 to 30 ring carbon atoms, and -* represents a bond to one of C1 to C4 c1 to c3 are each independently 0 or 1, R 61 to R 66 each independently is a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a substituted or unsubstituted silyl group, a substituted or unsubstituted thio group, a substituted or unsubstituted oxy group, a substituted or unsubstituted amino group, a substituted or unsubstituted boron 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 aryl group having 6 to 60 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 60 ring carbon atoms, or is bonded to an adjacent group to form a ring, and d1 to d4 are each independently an integer selected from 0 to 4.

6. The light-emitting element according to claim 1, wherein the second emission layer further comprises a (2-2) compound represented by Formula E-1: Formula E-1 wherein in Formula E-1, R 31 to R 40 each independently represents a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted silyl group, a substituted or unsubstituted thio group, a substituted or unsubstituted oxy group, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, or is bonded to an adjacent group to form a ring, and c and d are each independently an integer selected from 0 to 5.

7. The light-emitting element according to claim 1, wherein the (1-1) compound is represented by one of Formula 1-1 to Formula 1-3: Formula 1-1 Formula 1-2 Formula 1-3 wherein in Formula 1-1 to Formula 1-3, Y1 to Y8, Z1 and Z2 are each independently a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a hydroxyl group, a substituted or unsubstituted oxy group, a substituted or unsubstituted thio group, a substituted or unsubstituted seleno group, a substituted or unsubstituted telluro group, a substituted or unsubstituted germanium group, a substituted or unsubstituted boron group, a substituted or unsubstituted silyl group, a substituted or unsubstituted amino 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 aryl group having 6 to 30 ring carbon atoms or a substituted or unsubstituted heteroaryl group having 2 to 30 ring carbon atoms, or bonded to an adjacent group to form a ring, m1 to m8 are each independently an integer selected from 0 to 4, p1 and p2 are each independently an integer selected from 0 to 5, and R1, R3 to R 11 , X1 to X6, and n1 to n6 are the same as defined in Formula 1.

8. The light-emitting element according to claim 1, wherein the (1-1) compound is represented by Formula 1-4: Formula 1-4 wherein in Formula 1-4, Q1 and Q2 are each independently O, S, Se, Te or N(R 30 ), R 21 to R 30 each independently is a hydrogen atom, a deuterium atom, a halogen atom, a cyano 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 aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, or is bonded to an adjacent group to form a ring, and R5 to R 11 、X1 to X6 and n1 to n6 are the same as defined in Formula 1.

9. The light-emitting element according to claim 1, wherein in Formula 2, R 16 , R y1 , R y2 , R z1 and at least one of Ar are each independently a group represented by one of Formulas 4-1 to 4-4: Formula 4-1 Formula 4-2 Formula 4-3 Formula 4-4 wherein in Formula 4-1 to Formula 4-4, L1 to L4 are each independently a direct bond or a substituted or unsubstituted arylene group having 6 to 30 ring carbon atoms, R a1 to R a4 each independently represents a hydrogen atom, a deuterium atom, 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 2 to 30 ring carbon atoms, or is bonded to an adjacent group to form a ring, a1 and a2 are each independently an integer selected from 0 to 9, a3 is an integer selected from 0 to 7, a4 is an integer selected from 0 to 8, and *- represents a bond with Formula 2.

10. The light-emitting element according to claim 9, wherein the (2-1) compound is represented by Formula 2-1: Formula 2-1 Wherein in Formula 2-1, R b1 is a hydrogen atom, a deuterium atom, 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 aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring carbon atoms, R y1 、R y2 、R z1 and R b1 at least one of which is independently a group represented by one of Formula 4-1 to Formula 4-4 b1 is an integer selected from 0 to 5, and X, R 12 to R 17 , R x1 to R x3 , R y1 , R y2 , R z1 , x1 to x3, y1, y2 and z1 are the same as those defined in Formula 2.

11. The light-emitting element according to claim 1, wherein the (1-1) compound includes at least one compound selected from the compound group 1-1: Compound group 1-1 Wherein in the compound group 1-1, D represents a deuterium atom.

12. The light-emitting element according to claim 1, wherein the (2-1) compound includes at least one compound selected from the compound group 2-1: Compound group 2-1 Wherein in the compound group 2-1, D represents a deuterium atom.

13. A display device, comprising: A circuit layer disposed on a base layer; And A display element layer disposed on the circuit layer, Wherein the display element layer includes the light-emitting element according to any one of claims 1 to 12.

Images