Organic compound, organic light-emitting diode comprising the organic compound, and organic light-emitting device

Abstract

The present disclosure relates to an organic compound, an organic light-emitting diode (OLED), and an organic light-emitting device including the organic compound. In the organic compound, an electron acceptor part and an electron donor part of a fused aromatic ring or a heteroaromatic ring are directly connected or connected through a connecting part, and they are connected via a carbon-carbon bond. The organic compound includes both an electron acceptor part and an electron donor part having a strong bond energy in its molecule, which are directly connected or connected via a carbon-carbon bond through a connecting part, so that charges can be easily transported within the molecule. The OLED and the organic light-emitting device including the organic compound in the light-emitting layer can achieve excellent luminous efficiency and luminous lifetime.

Description

[0001] Cross - reference to related applications

[0002] This application claims the priority benefit of Korean Patent Application No. 10 - 2020 - 0115964, filed on September 10, 2020, which is hereby incorporated by reference in its entirety. Technical field

[0003] The present disclosure relates to organic compounds, and more particularly, to organic compounds having excellent light - emitting characteristics, organic light - emitting diodes, and organic light - emitting devices including the organic compounds. Background art

[0004] As display devices become larger, there is a need for flat - panel display devices with lower space requirements. Among the flat - panel display devices widely used currently, displays with organic light - emitting diodes (OLEDs) are rapidly replacing liquid - crystal display devices (LCDs).

[0005] The OLED can be formed into a thin film with a thickness less than and can implement a unidirectional or bidirectional image according to the electrode configuration. In addition, the OLED can be formed on a flexible transparent substrate such as a plastic substrate, so that the OLED can easily implement a flexible or foldable display. In addition, the OLED can be driven at a relatively low voltage of 10V or less. In addition, compared with plasma display panels and inorganic electroluminescent devices, the OLED has a relatively low driving power consumption, and the color purity of the OLED is very high. In particular, the OLED can implement red, green, and blue, and thus has attracted wide attention as a light - emitting device.

[0006] In an OLED, holes injected from the anode and electrons injected from the cathode recombine in the EML to form excitons as unstable excited states, and then emit light when the excitons transfer to the stable ground state. Ordinary fluorescent materials in which only singlet excitons participate in the light - emitting process have low light - emitting efficiency. Ordinary phosphorescent materials in which both triplet excitons and singlet excitons participate in the light - emitting process have relatively high light - emitting efficiency. However, metal complexes (representative phosphorescent materials) have too short a light - emitting lifetime to be applicable to commercial devices. Summary of the invention

[0007] Accordingly, the present disclosure relates to an organic compound, an OLED, and an organic light - emitting device including the organic compound, which substantially eliminate one or more problems caused by the limitations and disadvantages of the related art.

[0008] In addition, the present disclosure provides an organic compound having excellent light - emitting efficiency, an OLED, and an organic light - emitting device in which the organic compound is applied.

[0009] In addition, the present disclosure provides an OLED that improves its color purity and an organic light-emitting device having the OLED.

[0010] Additional features and aspects will be set forth in the following description, and some will be apparent from the description, or may be learned by practice of the inventive concepts provided herein. Other features and aspects of the inventive concepts may be realized and obtained by means of the structures particularly pointed out in the written description or claims hereof as well as the drawings.

[0011] To achieve these and other aspects of the present disclosure, as presented and broadly described, the present disclosure provides an organic compound having a structure of Formula 1:

[0012] [Formula 1]

[0013] A - [L - D] m

[0014] wherein A is an aromatic ring or heteroaromatic ring having a structure of Formula 2; L is a single bond or an aromatic ring or heteroaromatic ring having a structure of Formula 3; D is a fused aromatic ring or fused heteroaromatic ring having a structure of Formula 4; and m is an integer from 1 to 5;

[0015] [Formula 2]

[0016]

[0017] wherein one to five of A1 to A6 are carbon atoms connected to L or D and the remainder of A1 to A6 are independently CR1 or N, wherein R1 is independently hydrogen, cyano, nitro, a halogen atom, an unsubstituted or substituted C1 - C 20 alkyl, an unsubstituted or substituted C1 - C 20 alkylamino, an unsubstituted or substituted C6 - C 30 aromatic group or an unsubstituted or substituted C3 - C 20 heteroaromatic group, or adjacent two of the remainder of A1 to A6 form an unsubstituted or substituted C6 - C 20 aromatic ring or an unsubstituted or substituted C3 - C 20 heteroaromatic ring;

[0018] [Formula 3]

[0019]

[0020] wherein two of B1 to B6 are respectively carbon atoms connected to A and D and the remainder of B1 to B6 are independently CR2 or N, wherein R2 is independently hydrogen, cyano, nitro, a halogen atom, an unsubstituted or substituted C1 - C 20alkyl, unsubstituted or substituted C1-C 20 alkylamino, unsubstituted or substituted C6-C 30 aromatic group or unsubstituted or substituted C3-C 20 heteroaromatic group, or adjacent ones of the remainder of B1 to B6 form an unsubstituted or substituted C6-C 20 aromatic ring or unsubstituted or substituted C3-C 20 heteroaromatic ring;

[0021] [Formula 4]

[0022]

[0023] wherein X1 to X4 are each independently a single bond, CR3R4, NR5, O or S, wherein R3 to R5 are each independently hydrogen, unsubstituted or substituted C1-C 20 alkyl, unsubstituted or substituted C6-C 30 aromatic group or unsubstituted or substituted C3-C 20 heteroaromatic group, and at least one of X1 and X2 is not a single bond, and at least one of X3 and X4 is not a single bond; one of Y1 to Y 10 is a carbon atom connected to A or L and the remainder of Y1 to Y 10 are independently CR6 or N, wherein R6 is independently hydrogen, unsubstituted or substituted C1-C 20 alkyl, unsubstituted or substituted C6-C 30 aromatic group or unsubstituted or substituted C3-C 20 heteroaromatic group, or two of the remainder of Y1 to Y 10 form an unsubstituted or substituted C6-C 20 aromatic ring or unsubstituted or substituted C3-C 20 heteroaromatic ring; and p and q are each independently an integer from 0 to 2.

[0024] In another aspect, the present disclosure provides an OLED including a first electrode; a second electrode facing the first electrode; and a light-emitting layer disposed between the first electrode and the second electrode, wherein the light-emitting layer contains the organic compound.

[0025] For example, at least one light-emitting material in the light-emitting layer may contain the organic compound as a delayed fluorescence material. At least one light-emitting material layer may also contain at least one host and optionally at least one fluorescent or phosphorescent material.

[0026] As an example, the light-emitting layer may have a single light-emitting part or a plurality of light-emitting parts and at least one charge generation layer disposed between the plurality of light-emitting parts to form a tandem structure.

[0027] At least one light-emitting material layer in at least one of the plurality of light-emitting parts may contain the organic compound.

[0028] In another aspect, the present disclosure provides an organic light-emitting device including a substrate and an OLED disposed above the substrate as described above, such as an organic light-emitting display device and an organic light-emitting lighting device.

[0029] It should be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the inventive concept as claimed. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The drawings, which are included to provide a further understanding of the present disclosure, are incorporated in and constitute a part of the present disclosure, illustrate aspects of the present disclosure, and together with the description are used to explain the principles of the present disclosure.

[0031] Figure 1 is a schematic circuit diagram showing an organic light-emitting display device according to an exemplary aspect of the present disclosure.

[0032] Figure 2 is a schematic cross-sectional view showing an organic light-emitting display device according to an exemplary aspect of the present disclosure.

[0033] Figure 3 is a schematic cross-sectional view showing an OLED according to an exemplary aspect of the present disclosure.

[0034] Figure 4 is a schematic diagram showing a light-emitting mechanism through the energy level band gaps between light-emitting materials according to an exemplary aspect of the present disclosure.

[0035] Figure 5 is a schematic diagram showing a light-emitting mechanism through the energy level band gaps between light-emitting materials according to another exemplary aspect of the present disclosure.

[0036] Figure 6 is a schematic cross-sectional view showing an OLED according to yet another exemplary aspect of the present disclosure.

[0037] Figure 7 is a schematic diagram showing a light-emitting mechanism through the energy level band gaps between light-emitting materials according to yet another exemplary aspect of the present disclosure.

[0038] Figure 8It is a schematic cross-sectional view of an OLED showing yet another exemplary aspect according to the present disclosure.

[0039] Figure 9 It is a schematic diagram showing the light-emitting mechanism through the energy level bandgap between light-emitting materials according to yet another exemplary aspect of the present disclosure.

[0040] Figure 10 It is a schematic cross-sectional view of an OLED showing yet another exemplary aspect according to the present disclosure.

[0041] Figure 11 It is a schematic cross-sectional view of an organic light-emitting display device showing another exemplary aspect according to the present disclosure.

[0042] Figure 12 It is a schematic cross-sectional view of an OLED showing yet another exemplary aspect according to the present disclosure.

[0043] Figure 13 It is a schematic cross-sectional view of an organic light-emitting display device showing yet another exemplary aspect according to the present disclosure.

[0044] Figure 14 It is a schematic cross-sectional view of an OLED showing yet another exemplary aspect according to the present disclosure.

[0045] Figure 15 It is a schematic cross-sectional view of an OLED showing yet another exemplary aspect according to the present disclosure. Detailed Description

[0046] Aspects and examples of the present disclosure will now be referred to and discussed in detail below, some of which are shown in the accompanying drawings.

[0047] [Organic Compound]

[0048] The organic compound applied to an organic light-emitting diode (OLED) should have excellent light-emitting characteristics, high charge affinity, and stable characteristics when driving the OLED. In particular, the light-emitting material applied to the OLED is the most important factor determining the light-emitting efficiency of the OLED. The light-emitting material should have a high quantum efficiency, large charge mobility, and sufficient energy levels relative to other materials applied to the same layer or adjacent layers.

[0049] The organic compound of the present disclosure has both an electron donor part and an electron acceptor part within its molecular structure, and thus it can exhibit delayed fluorescence characteristics. The organic compound of the present disclosure may have the structure of Formula 1:

[0050] [Formula 1]

[0051] A - [L - D]m

[0052] Wherein A is an aromatic ring or heteroaromatic ring having the structure of Formula 2; L is a single bond or an aromatic ring or heteroaromatic ring having the structure of Formula 3; D is a fused aromatic ring or fused heteroaromatic ring having the structure of Formula 4; and m is an integer from 1 to 5;

[0053] [Formula 2]

[0054]

[0055] Wherein one to five of A1 to A6 are carbon atoms connected to L or D and the remainder of A1 to A6 are independently CR1 or N, wherein R1 is independently hydrogen, cyano, nitro, a halogen atom, an unsubstituted or substituted C1-C 20 alkyl group, an unsubstituted or substituted C1-C 20 alkylamino group, an unsubstituted or substituted C6-C 30 aromatic group or an unsubstituted or substituted C3-C 20 heteroaromatic group, or two adjacent ones of the remainder of A1 to A6 form an unsubstituted or substituted C6-C 20 aromatic ring or an unsubstituted or substituted C3-C 20 heteroaromatic ring;

[0056] [Formula 3]

[0057]

[0058] Wherein two of B1 to B6 are respectively carbon atoms connected to A and D and the remainder of B1 to B6 are independently CR2 or N, wherein R2 is independently hydrogen, cyano, nitro, a halogen atom, an unsubstituted or substituted C1-C 20 alkyl group, an unsubstituted or substituted C1-C 20 alkylamino group, an unsubstituted or substituted C6-C 30 aromatic group or an unsubstituted or substituted C3-C 20 heteroaromatic group, or two adjacent ones of the remainder of B1 to B6 form an unsubstituted or substituted C6-C 20 aromatic ring or an unsubstituted or substituted C3-C 20 heteroaromatic ring;

[0059] [Formula 4]

[0060]

[0061] wherein X1 to X4 are each independently a single bond, CR3R4, NR5, O or S, wherein R3 to R5 are each independently hydrogen, unsubstituted or substituted C1-C 20 alkyl, unsubstituted or substituted C6-C 30 aromatic group or unsubstituted or substituted C3-C 20 heteroaromatic group, and wherein at least one of X1 and X2 is not a single bond, and at least one of X3 and X4 is not a single bond; one of Y1 to Y 10 is a carbon atom connected to A or L and the remainder of Y1 to Y 10 are each independently CR6 or N, wherein R6 is independently hydrogen, unsubstituted or substituted C1-C 20 alkyl, unsubstituted or substituted C6-C 30 aromatic group or unsubstituted or substituted C3-C 20 heteroaromatic group, or two of the remainder of Y1 to Y 10 form an unsubstituted or substituted C6-C 20 aromatic ring or an unsubstituted or substituted C3-C 20 heteroaromatic ring; and p and q are each independently an integer from 0 to 2.

[0062] As used herein, the term "unsubstituted" means attached to hydrogen, and in this case, hydrogen includes protium, deuterium and tritium.

[0063] As used herein, the substituents in the term "substituted" include: unsubstituted or halogen-substituted C1-C 20 alkyl, unsubstituted or halogen-substituted C1-C 20 alkoxy, halogen, cyano, -CF3, hydroxy, carboxy, carbonyl, amino, C1-C 10 alkylamino, C6-C 30 arylamino, C3-C 30 heteroarylamino, C6-C 30 aryl, C3-C 30 heteroaryl, nitro, hydrazino, sulfonate / ester group, C1-C 20 alkylsilyl, C6-C 30 arylsilyl and C3-C 30 heteroarylsilyl, but not limited to this.

[0064] As used herein, the term "hetero" in, for example, "heteroaromatic ring", "heterocycloalkylidene", "heteroarylene", "heteroarylalkyl", "heteroaryloxy", "heterocycloalkyl", "heteroaryl", "heteroarylalkyl", "heteroaryloxy", "heteroarylamino" means that at least one carbon atom, for example 1 to 5 carbon atoms, constituting an aromatic ring or an alicyclic ring is replaced by at least one heteroatom selected from N, O, S, P, and combinations thereof.

[0065] As an example, the alkyl and alkylamino groups of R1 to R6 may each be independently unsubstituted or substituted by at least one halogen atom, but are not limited thereto. The aromatic groups, heteroaromatic groups, aromatic rings, and heteroaromatic rings of R1 to R6 may each be independently unsubstituted or substituted by at least one of a cyano group, a nitro group, and a halogen group, but are not limited thereto.

[0066] In one exemplary aspect, when each of R1 to R6 is independently a C6-C 30 aromatic group, each of R1 to R6 may independently be a C6-C 30 aryl, a C7-C 30 arylalkyl, a C6-C 30 aryloxy, and a C6-C 30 arylamino, but are not limited thereto. In another exemplary aspect, when each of R1 to R6 is independently a C3-C 30 heteroaromatic group, each of R1 to R6 may independently be a C3-C 30 heteroaryl, a C4-C 30 heteroarylalkyl, a C3-C 30 heteroaryloxy, and a C3-C 30 heteroarylamino, but are not limited thereto.

[0067] As an example, when each of R1 to R6 is independently a C6-C 30 aryl, each of R1 to R6 may independently include, but is not limited to, an un-fused or fused aryl, such as phenyl, biphenyl, terphenyl, naphthyl, anthracenyl, cyclopentadienyl, indenyl, indeno-indenyl, heptaleneyl, biphenylene, indacenyl, phenalenyl, phenanthryl, benzo-phenanthryl, dibenzo-phenanthryl, azulenyl, pyrenyl, fluoranthenyl, triphenylene, yl, tetraphenylene, pentaphenylene, pleiadenyl, picenyl, hexaphenylene, hexa-phenylene, fluoreneyl, indeno-fluoreneyl, and spiro-fluoreneyl.

[0068] In another exemplary aspect, when each of R1 to R6 is independently a C3-C 30When R1 to R6 are heteroaryl groups, each of R1 to R6 can independently include, but is not limited to, un-fused or fused heteroaryl groups such as pyrrolyl, pyridinyl, pyrimidinyl, pyrazinyl, pyridazinyl, triazinyl, tetrazinyl, imidazolyl, pyrazolyl, indolyl, isoindolyl, indazolyl, indazinyl, pyrrolizinyl, carbazolyl, benzo[c]carbazolyl, dibenzo[c]carbazolyl, indolo[c]carbazolyl, indeno[c]carbazolyl, benzofuro[c]carbazolyl, benzothieno[c]carbazolyl, carbolinyl, quinolinyl, isoquinolinyl, phthalazinyl, quinoxalinyl, cinnolinyl, quinazolinyl, quinazolinyl, purinyl, benzoquinolinyl, benzoisoquinolinyl, benzquinazolinyl, benzquinoxalinyl, acridinyl, phenazinyl, phen azinyl, phenothiazinyl, phenanthrolinyl, perimidinyl, phenanthridinyl, pteridinyl, naphthyridinyl, furyl, pyranyl, azinyl, azolyl, diazolyl, triazolyl, di enyl, benzofuryl, dibenzofuryl, thianyl, xanthenyl, chromenyl, isochromenyl, thiazinyl, thienyl, benzothienyl, dibenzothienyl, difuro[3,2-b]pyrazinyl, benzofuro[3,2-b]dibenzofuryl, benzothieno[3,2-b]benzothienyl, benzothieno[3,2-b]dibenzothienyl, benzothieno[3,2-b]benzofuryl, benzothieno[3,2-b]dibenzofuryl, spiroacridinyl linked to xanthene, dihydroacridinyl substituted with at least one C1-C 10 alkyl, and N-substituted spirofluorene.

[0069] As an example, when each of R1 to R6 is an aromatic group or a heteroaromatic group, each of R1 to R6 can independently be phenyl, biphenyl, pyrrolyl, triazinyl, imidazolyl, pyrazolyl, pyridinyl, pyrazinyl, pyrimidinyl, pyridazinyl, furyl, benzofuryl, dibenzofuryl, thienyl, benzothienyl, dibenzothienyl, and carbazolyl, but is not limited thereto.

[0070] Alternatively, two adjacent ones of each R1, two adjacent ones of each R2, two adjacent ones of R3 to R5, and two adjacent ones of each R6 can form a C6-C 20 aromatic ring or a C3-C 20 heteroaromatic ring. As an example, when two adjacent ones of each R1, two adjacent ones of each R2, two adjacent ones of R3 to R5, and two adjacent ones of each R6 in Formulas 2 to 4 form an aromatic ring or a heteroaromatic ring, the formed aromatic ring or heteroaromatic ring can be, but is not limited to, an aryl ring (such as a benzene ring and / or a naphthalene ring) or a heteroaryl ring (such as a pyrimidine ring and / or a carbazole ring).

[0071] In one exemplary aspect, at least one of R1 and R2 can include a cyano group, a nitro group, a halogen atom, a C1-C 10An alkyl group, a C6-C substituted with at least one of cyano, nitro, and halogen 30 aromatic group, and a C3-C substituted with at least one of cyano, nitro, and halogen 30 heteroaromatic group, but not limited thereto.

[0072] In another exemplary aspect, one of X1 and X2 can be a single bond and the other of X1 and X2 can be NR5, one of X3 and X4 can be a single bond and the other of X3 and X4 can be NR5, p and q can each independently be 1, and one of Y1 to Y 10 can be a carbon atom connected to L and the remainder of Y1 to Y 10 can independently be CR6, but not limited thereto.

[0073] The organic compound having the structure of Formula 1 has an aromatic or heteroaromatic part (A part) of an electron acceptor moiety, a fused aromatic or fused heteroaromatic part (D part) of an electron donor moiety, and an optional aromatic or heteroaromatic linking part (L part) between the electron acceptor moiety and the electron donor moiety.

[0074] Due to the steric hindrance between the fused aromatic or fused heteroaromatic part of the electron donor and the aromatic or heteroaromatic part of the electron acceptor, the formation of a conjugated structure between these parts is restricted. The molecule is easily divided into the highest occupied molecular orbital (HOMO) energy state and the lowest unoccupied molecular orbital (LUMO) energy state, and a dipole between the electron acceptor part and the electron donor part. Therefore, the organic compound has excellent luminescence efficiency due to an increased intramolecular dipole moment.

[0075] When the electron donor part and the electron acceptor part are separated, the energy overlap between the HOMO energy state and the LUMO energy state within the molecule is reduced. Therefore, the organic compound having the structure of Formula 1 has a very narrow singlet energy level S1 DF and triplet energy level T1 DF and the energy band gap ΔE ST ( Figure 4 ).

[0076] As an example, the energy band gap ΔE DF between the singlet energy level S1 DF and the triplet energy level T1 ST of the organic compound having the structure of Formula 1 can be equal to or less than about 0.3 eV, for example, about 0.05 eV to about 0.3 eV. In the case of driving an OLED D1 containing the organic compound having the structure of Formula 1, the exciton of the singlet energy level S1 DF and the exciton of the triplet energy level T1 DF can be thermally transferred to an intermediate energy level state, i.e., the ICT (intramolecular charge transfer) state (S1DF →ICT←T1 DF ), and then the intermediate state exciton can be transferred to the ground state (ICT→S0). Since the organic compound emits light when the exciton is in the ICT state transferred to the ground state, theoretically it can have an internal quantum efficiency of 100%.

[0077] In other words, since the organic compound having the structure of Formula 1 has a small energy band gap between the singlet state and the triplet state, it can exhibit ordinary fluorescence through intersystem crossing (ISC) (wherein the exciton of the singlet state energy level S1 can be transferred to its ground state S0), and delayed fluorescence through reverse intersystem crossing (RISC) (wherein the exciton of the triplet state energy level T1 can be transferred upward to the exciton of the singlet state energy level S1, and then the exciton of the singlet state energy level S1 can be transferred to the ground state S0 to achieve delayed fluorescence).

[0078] In addition, the organic compound having the structure of Formula 1 includes a rigid electron donor part (D part) of a fused aromatic or heteroaromatic ring, such that its molecular conformation is greatly restricted. Since the energy loss caused by the change of the molecular conformation when the organic compound emits light is small, and the photoluminescence spectrum of the organic compound can be in a specific range, high color purity can be achieved.

[0079] In addition, the organic compound having the structure of Formula 1 can have a triplet state energy level T1 smaller than that of ordinary phosphorescent materials DF , and can have a narrower energy band gap than phosphorescent materials. Therefore, it is not necessary to use an organic compound having a high triplet state energy level and a wide energy band gap as the host, which limits the use of ordinary phosphorescent materials as dopants. In addition, the delay of charge injection and transport caused by the host having a wide energy band gap can be minimized.

[0080] In addition, the organic compound having the structure of Formula 1 includes an electron acceptor part (A part), an aromatic or heteroaromatic linking part (L part), and an electron donor part (D part) which are respectively connected by carbon-carbon linkages. Due to the carbon-carbon linkages having strong bond energy, the organic compound having the structure of Formula 1 has excellent thermal stability. Since the organic compound is not deteriorated due to the heat generated when driving the OLED, it can achieve excellent luminous efficiency and luminous lifetime.

[0081] In one exemplary aspect, one of A1 to A6 constituting the electron acceptor portion (portion A) may be a carbon atom connected to the linking portion (portion L) or the electron donor portion (portion D), and at least one of A1 to A6 not connected to the L portion or the D portion may be nitrogen (N). In another exemplary aspect, one of A1 to A6 constituting the electron acceptor portion (portion A) may be a carbon atom connected to the linking portion (portion L) or the electron donor portion (portion D), and at least two of A1 to A6 not connected to the L portion or the D portion may be nitrogen (N).

[0082] Alternatively, at least one carbon atom of the carbon atoms constituting the A portion not connected to the L portion or the D portion may be substituted with: a halogen atom, a cyano group, a nitro group, an unsubstituted or halogen-substituted C1-C 10 alkyl group, an unsubstituted or halogen-substituted C1-C 10 alkylamino group, a C6-C 30 aryl group unsubstituted or substituted with halogen, cyano, nitro or a combination thereof, or a C3-C 30 heteroaryl group, but not limited thereto.

[0083] In one exemplary aspect, the D portion of the electron donor portion may have a structure in which two six-membered rings are on both sides, and at least one five-membered ring and at least one six-membered ring fused ring are between the two six-membered rings. Such a D portion may have a structure of Formula 5 or Formula 6:

[0084] [Formula 5]

[0085]

[0086] [Formula 6]

[0087]

[0088] wherein B has a structure of Formula 7; E has a structure of Formula 8; one of R 11 to R 18 is a carbon atom connected to A or L and the remainder of R 11 to R 18 are independently hydrogen, an unsubstituted or substituted C1-C 20 alkyl group, an unsubstituted or substituted C6-C 30 aryl group or an unsubstituted or substituted C3-C 20 heteroaryl group; one of R 19 to R 28 is a carbon atom connected to A or L and R 19 to R 28The remainder is independently hydrogen, unsubstituted or substituted C1-C 20 alkyl, unsubstituted or substituted C6-C 30 aryl, or unsubstituted or substituted C3-C 20 heteroaryl;

[0089] [Formula 7]

[0090]

[0091] [Formula 8]

[0092]

[0093] wherein R 31 and R 32 are each independently hydrogen, unsubstituted or substituted C1-C 20 alkyl, unsubstituted or substituted C6-C 30 aryl, or unsubstituted or substituted C3-C 20 heteroaryl; Z1 and Z2 are each independently NR 33 , O or S, wherein R 33 is hydrogen, unsubstituted or substituted C1-C 20 alkyl, unsubstituted or substituted C6-C 30 aryl, or unsubstituted or substituted C3-C 20 heteroaryl.

[0094] In addition, the A part of the electron acceptor moiety in Formula 1 may include a triazine moiety having three nitrogen atoms as nuclear atoms. The organic compound containing the triazine moiety as the A part may be selected from the compounds of Formula 9 below:

[0095] [Formula 9]

[0096]

[0097]

[0098]

[0099] Alternatively, the A part in Formula 1 may include a pyrimidine moiety or a pyrazine moiety having two nitrogen atoms as nuclear atoms. The organic compound containing the pyrimidine moiety or the pyrazine moiety as the A part may be selected from the compounds of Formula 10 below:

[0100] [Formula 10]

[0101]

[0102]

[0103]

[0104]

[0105]

[0106]

[0107]

[0108]

[0109]

[0110] In yet another aspect, the moiety A in Formula 1 may include a pyridine moiety having one nitrogen atom as a core atom. The organic compound containing the pyridine moiety as moiety A may be selected from the compounds of Formula 11 below:

[0111] [Formula 11]

[0112]

[0113]

[0114]

[0115]

[0116]

[0117]

[0118] In yet another aspect, the moiety A in Formula 1 may include a phenyl moiety having only carbon atoms as core atoms. In this case, at least one carbon atom, for example two carbon atoms, of the phenyl moiety as a core atom may be substituted with a cyano group, a nitro group, and combinations thereof, but not limited thereto. As an example, the organic compound containing the phenyl moiety as moiety A may be selected from the compounds of Formula 12 below:

[0119] [Formula 12]

[0120]

[0121]

[0122]

[0123]

[0124]

[0125] [Organic Light-Emitting Device and OLED]

[0126] By applying an organic compound having a structure of Formula 1 to 12 to a light-emitting layer, such as a light-emitting material layer of an OLED, an OLED having excellent luminous efficiency and improved luminous lifetime can be achieved. The OLEDs of the present disclosure can be applied to organic light-emitting devices such as organic light-emitting display devices or organic light-emitting lighting devices. An organic light-emitting display device including an OLED will be described. Figure 1 is a schematic circuit diagram showing an organic light-emitting display device according to an exemplary aspect of the present disclosure.

[0127] As Figure 1 shown, in the organic light-emitting display device, gate lines GL, data lines DL, and power supply lines PL cross each other to define a pixel region P. A switching thin-film transistor Ts, a driving thin-film transistor Td, a storage capacitor Cst, and an organic light-emitting diode D are formed within the pixel region P. The pixel region P may include a first pixel region P1, a second pixel region P2, and a third pixel region P3 (see Figure 11 ).

[0128] The switching thin-film transistor Ts is connected to the gate line GL and the data line DL, and the driving thin-film transistor Td and the storage capacitor Cst are connected between the switching thin-film transistor Ts and the power supply line PL. The organic light-emitting diode D is connected to the driving thin-film transistor Td. When the switching thin-film transistor Ts is turned on by a gate signal applied to the gate line GL, a data signal applied to the data line DL is applied to the gate electrode of the driving thin-film transistor Td and one electrode of the storage capacitor Cst through the switching thin-film transistor Ts.

[0129] The driving thin-film transistor Td is turned on by the data signal applied to the gate electrode, so that a current proportional to the data signal is supplied from the power supply line PL to the organic light-emitting diode D through the driving thin-film transistor Td. Then, the organic light-emitting diode D emits light having a luminance proportional to the current flowing through the driving thin-film transistor Td. In this case, the storage capacitor Cst is charged with a voltage proportional to the data signal, so that the voltage of the gate electrode in the driving thin-film transistor Td remains constant during one frame. Therefore, the organic light-emitting display device can display a desired image.

[0130] Figure 2 is a schematic cross-sectional view of an organic light-emitting display device 100 according to an exemplary aspect of the present disclosure. All components of the organic light-emitting display device according to all aspects of the present disclosure are operably coupled and configured. As Figure 2As shown, the organic light-emitting display device 100 includes a substrate 110, a thin-film transistor Tr on the substrate 110, and an organic light-emitting diode (OLED) D connected to the thin-film transistor Tr.

[0131] The substrate 110 may include glass, a thin flexible material, and / or polymer plastics, but is not limited thereto. For example, the flexible material may be selected from the group consisting of polyimide (PI), polyethersulfone (PES), polyethylene naphthalate (PEN), polyethylene terephthalate (PET), polycarbonate (PC), and combinations thereof, but is not limited thereto. The substrate 110 on which the thin-film transistor Tr and the OLED D are disposed forms an array substrate.

[0132] A buffer layer 122 may be provided above the substrate 110, and the thin-film transistor Tr is disposed above the buffer layer 122. The buffer layer 122 may be omitted.

[0133] A semiconductor layer 120 is disposed above the buffer layer 122. In an exemplary aspect, the semiconductor layer 120 may include an oxide semiconductor material, but is not limited thereto. In this case, a light-shielding pattern may be provided below the semiconductor layer 120, and the light-shielding pattern may prevent light from incident on the semiconductor layer 120, thereby preventing the semiconductor layer 120 from deteriorating due to light. Alternatively, the semiconductor layer 120 may include polysilicon, but is not limited thereto. In this case, opposite edges of the semiconductor layer 120 may be doped with impurities.

[0134] A gate insulating layer 124 formed of an insulating material is disposed on the semiconductor layer 120. The gate insulating layer 124 may include, but is not limited to, an inorganic insulating material such as silicon oxide (SiO x ) or silicon nitride (SiN x ).

[0135] A gate electrode 130 made of a conductive material such as metal is disposed above the gate insulating layer 124 corresponding to the center of the semiconductor layer 120. Although in Figure 1 the gate insulating layer 124 is disposed above the entire area of the substrate 110, the gate insulating layer 124 may be patterned in the same manner as the gate electrode 130.

[0136] An interlayer insulating layer 132 formed of an insulating material is disposed on the gate electrode 130, covering above the entire surface of the substrate 110. The interlayer insulating layer 132 may include, but is not limited to, an inorganic insulating material such as silicon oxide (SiO x ) or silicon nitride (SiN x ), or an organic insulating material such as benzocyclobutene or photo-acryl.

[0137] The interlayer insulating layer 132 has a first semiconductor layer contact hole 134 and a second semiconductor layer contact hole 136 that expose both sides of the semiconductor layer 120. The first semiconductor layer contact hole 134 and the second semiconductor layer contact hole 136 are disposed above opposite sides of the gate electrode 130 and spaced apart from the gate electrode 130. The first semiconductor layer contact hole 134 and the second semiconductor layer contact hole 136 are formed in Figure 2 the gate insulating layer 124 in. Alternatively, when the gate insulating layer 124 is patterned in the same manner as the gate electrode 130, the first semiconductor layer contact hole 134 and the second semiconductor layer contact hole 136 are formed only in the interlayer insulating layer 132.

[0138] A source electrode 144 and a drain electrode 146 formed of a conductive material such as metal are disposed on the interlayer insulating layer 132. The source electrode 144 and the drain electrode 146 are spaced apart from each other with respect to the gate electrode 130, and the source electrode 144 and the drain electrode 146 contact both sides of the semiconductor layer 120 through the first semiconductor layer contact hole 134 and the second semiconductor layer contact hole 136, respectively.

[0139] The semiconductor layer 120, the gate electrode 130, the source electrode 144, and the drain electrode 146 constitute a thin film transistor Tr serving as a driving element. Figure 2 The thin film transistor Tr in has a coplanar structure in which the gate electrode 130, the source electrode 144, and the drain electrode 146 are disposed above the semiconductor layer 120. Alternatively, the thin film transistor Tr may have an inverted staggered structure in which the gate electrode is disposed below the semiconductor layer and the source electrode and the drain electrode are disposed above the semiconductor layer. In this case, the semiconductor layer may include amorphous silicon.

[0140] In Figure 1 the pixel region of, gate lines and data lines that cross each other to define the pixel region, and switching elements connected to the gate lines and the data lines may also be formed. The switching elements are connected to the thin film transistor Tr serving as a driving element. In addition, a power supply line is spaced apart in parallel from the gate line or the data line, and the thin film transistor Tr may further include a storage capacitor configured to constantly hold the voltage of the gate electrode for one frame.

[0141] In addition, the organic light emitting display device 100 may include a color filter including a dye or a pigment for transmitting specific wavelength light in the light emitted from the OLED D. For example, the color filter may transmit light of a specific wavelength, such as red (R), green (G), blue (B), and / or white (W). Each of the red, green, and blue color filters may be formed in each pixel region, respectively. In this case, the organic light emitting display device 100 may achieve full color through the color filter.

[0142] For example, when the organic light emitting display device 100 is a bottom emission type, the color filter may be disposed on the interlayer insulating layer 132 corresponding to the OLED D. Alternatively, when the organic light emitting display device 100 is a top emission type, the color filter may be disposed above the OLED D, that is, above the second electrode 230.

[0143] The passivation layer 150 is disposed on the source electrode 144 and the drain electrode 146 over the entire substrate 110. The passivation layer 150 has a flat top surface and a drain contact hole 152 exposing the drain electrode 146 of the thin film transistor Tr. Although the drain contact hole 152 is disposed on the second semiconductor layer contact hole 136, it may be spaced apart from the second semiconductor layer contact hole 136.

[0144] The OLED D includes a first electrode 210 disposed on the passivation layer 150 and connected to the drain electrode 146 of the thin film transistor Tr. The OLED D further includes a light emitting layer 220 and a second electrode 230, the light emitting layer 220 including at least one light emitting portion, and each of the light emitting layer 220 and the second electrode 230 is sequentially disposed on the first electrode 210.

[0145] The first electrode 210 is disposed in each pixel region. The first electrode 210 may be an anode and include a conductive material having a relatively high work function value. For example, the first electrode 210 may include, but is not limited to, a transparent conductive oxide (TCO) such as indium tin oxide (ITO), indium zinc oxide (IZO), indium tin zinc oxide (ITZO), tin oxide (SnO), zinc oxide (ZnO), indium cerium oxide (ICO), aluminum-doped zinc oxide (AZO), etc.

[0146] In one exemplary aspect, when the organic light emitting display device 100 is a bottom emission type, the first electrode 210 may have a single layer structure of TCO. Alternatively, when the organic light emitting display device 100 is a top emission type, a reflective electrode or a reflective layer may be disposed below the first electrode 210. For example, the reflective electrode or the reflective layer may include silver (Ag) or an aluminum-palladium-copper (APC) alloy, but is not limited thereto. In the top emission type OLED D, the first electrode 210 may have a three-layer structure of ITO / Ag / ITO or ITO / APC / ITO.

[0147] In addition, a bank layer 160 is disposed on the passivation layer 150 to cover the edge of the first electrode 210. The bank layer 160 exposes the center of the first electrode 210.

[0148] The light-emitting layer 220 is disposed on the first electrode 210. In an exemplary aspect, the light-emitting layer 220 may have a single-layer structure of a light-emitting material layer (EML). Alternatively, the light-emitting layer 220 may have a multi-layer structure of a hole injection layer (HIL), a hole transport layer (HTL), an electron blocking layer (EBL), an EML, a hole blocking layer (HBL), an electron transport layer (ETL), and / or an electron injection layer (EIL) (see Figure 2 , 5 , 7, and 9). In one aspect, the light-emitting layer 220 may have a single light-emitting portion. Alternatively, the light-emitting layer 220 may have a plurality of light-emitting portions to form a tandem structure.

[0149] The light-emitting layer 220 includes any one of the structures of Formulas 1 to 12. As an example, an organic compound having the structure of Formulas 1 to 12 may be applied as a dopant in the EML.

[0150] The second electrode 230 is disposed above the substrate 110 on which the light-emitting layer 220 is disposed. The second electrode 230 may be disposed over the entire display area and may include a conductive material having a relatively low work function value compared to the first electrode 210. The second electrode 230 may be a cathode. For example, the second electrode 230 may include, but is not limited to, aluminum (Al), magnesium (Mg), calcium (Ca), silver (Ag), an alloy thereof, or a combination thereof such as an aluminum-magnesium alloy (Al-Mg). When the organic light-emitting display device 100 is a top-emitting type, the second electrode 230 is thin to have light transmission (semi-transmission) characteristics.

[0151] In addition, a encapsulation film 170 may be disposed above the second electrode 230 to prevent external moisture from penetrating into the OLED D. The encapsulation film 170 may have a laminated structure of a first inorganic insulating film 172, an organic insulating film 174, and a second inorganic insulating film 176, but is not limited thereto.

[0152] In addition, the organic light-emitting display device 100 may have a polarizer to reduce external light reflection. For example, the polarizer may be a circular polarizer. When the organic light-emitting display device 100 is a bottom-emitting type, the polarizer may be disposed below the substrate 110. Alternatively, when the organic light-emitting display device 100 is a top-emitting type, the polarizer may be disposed above the encapsulation film 170. In addition, a cover window may be attached to the encapsulation film 170 or the polarizer. In this case, the substrate 110 and the cover window may have flexible characteristics, and thus the organic light-emitting display device 100 may be a flexible display device.

[0153] We will describe the OLED in more detail. Figure 3 is a schematic cross-sectional view of an OLED showing an exemplary aspect in accordance with the present disclosure. As Figure 3As shown, the OLED D1 includes a first electrode 210 and a second electrode 230 facing each other, and a light-emitting layer 220 having a single light-emitting portion disposed between the first electrode 210 and the second electrode 230. The organic light-emitting display device 100 includes a red pixel region, a green pixel region, and a blue pixel region, and the OLED D1 may be disposed in the green pixel region.

[0154] In one exemplary aspect, the light-emitting layer 220 includes an EML 240 disposed between the first electrode 210 and the second electrode 230. In addition, the light-emitting layer 220 may include at least one of an HTL 260 disposed between the first electrode 210 and the EML 240, and an ETL 270 disposed between the second electrode 230 and the EML 240. In addition, the light-emitting layer 220 may further include at least one of a HIL 250 disposed between the first electrode 210 and the HTL 260 and an EIL 280 disposed between the second electrode 230 and the ETL 270. Alternatively, the light-emitting layer 220 may further include a first exciton blocking layer (i.e., EBL 265) disposed between the HTL 260 and the EML 240 and / or a second exciton blocking layer (i.e., HBL 275) disposed between the EML 240 and the ETL 270.

[0155] The first electrode 210 may be an anode that provides holes to the EML 240. The first electrode 210 may include, but is not limited to, a conductive material having a relatively high work function value, such as a transparent conductive oxide (TCO). In one exemplary aspect, the first electrode 210 may include ITO, IZO, ITZO, SnO, ZnO, ICO, AZO, etc., but is not limited thereto.

[0156] The second electrode 230 may be a cathode that provides electrons to the EML 240. The second electrode 230 may include, but is not limited to, a conductive material having a relatively low work function value, i.e., a high-reflection material, such as Al, Mg, Ca, Ag, its alloy, its combination, etc.

[0157] In this regard, the EML 240 may include a first compound (Compound 1, H) and a second compound (Compound 2) DF. For example, the first compound may be a (first) host, and the second compound DF may be a delayed fluorescence material. For example, the second compound DF in the EML 240 may include an organic compound having a structure of Formula 1 to 12. As an example, the EML 240 may emit green light. Hereinafter, we will describe the types of the first compound and the energy level relationship between the first compound H and the second compound DF.

[0158] The HIL 250 is disposed between the first electrode 210 and the HTL 260, and improves the interfacial characteristics between the inorganic first electrode 210 and the organic HTL 260. In an exemplary aspect, the HIL 250 may include 4,4′,4″-tris(3-methylphenylamino)triphenylamine (MTDATA), 4,4′,4″-tris(N,N-diphenyl-amino)triphenylamine (NATA), 4,4′,4″-tris(N-(naphthalen-1-yl)-N-phenyl-amino)triphenylamine (1T-NATA), 4,4′,4″-tris(N-(naphthalen-2-yl)-N-phenyl-amino)triphenylamine (2T-NATA), copper phthalocyanine (CuPc), tris(4-carbazol-9-yl-phenyl)amine (TCTA), N,N′-diphenyl-N,N′-bis(1-naphthyl)-1,1′-biphenyl-4,4″-diamine (NPB; NPD), 1,4,5,8,9,11-hexaazatriphenylenehexacarbonitrile (dipyrazino[2,3-f:2′,3′-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile; HAT-CN), 1,3,5-tris[4-(diphenylamino)phenyl]benzene (TDAPB), poly(3,4-ethylenedioxythiophene) polystyrenesulfonate / ester (PEDOT / PSS), N-(biphenyl-4-yl)-9,9-dimethyl-N-(4-(9-phenyl-9H-carbazol-3-yl)phenyl)-9H-fluorene-2-amine, and combinations thereof, but not limited thereto. The HIL 250 may be omitted according to the structure of the OLED D1.

[0159] The HTL 260 is disposed adjacent to the EML 240 between the first electrode 210 and the EML 240. In an exemplary aspect, the HTL 260 may include N,N′-diphenyl-N,N′-bis(3-methylphenyl)-1,1′-biphenyl-4,4′-diamine (TPD), NPB, 4,4′-bis(N-carbazolyl)-1,1′-biphenyl (CBP), poly[N,N′-bis(4-butylphenyl)-N,N′-bis(phenyl)-benzidine] (poly-TPD), poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(4,4′-(N-(4-sec-butylphenyl)diphenylamine))] (TFB), bis-[4-(N,N-di-p-tolyl-amino)-phenyl]cyclohexane (TAPC), 3,5-bis(9H-carbazol-9-yl)-N,N-diphenylamine (DCDPA), N-(biphenyl-4-yl)-9,9-dimethyl-N-(4-(9-phenyl-9H-carbazol-3-yl)phenyl)-9H-fluorene-2-amine, N-(biphenyl-4-yl)-N-(4-(9-phenyl-9H-carbazol-3-yl)phenyl)biphenyl-4-amine, and combinations thereof, but not limited thereto.

[0160] The ETL 270 and the EIL 280 can be sequentially laminated between the EML 240 and the second electrode 230. The ETL 270 includes a material having a high electron mobility to stably supply electrons to the EML 240 through fast electron transport.

[0161] In an exemplary aspect, the ETL 270 can include at least one of the following: based on diazole compounds, triazole-based compounds, phenanthroline-based compounds, benzoxazole-based compounds, benzothiazole-based compounds, benzimidazole-based compounds, triazine-based compounds, etc., but not limited thereto.

[0162] As an example, the ETL 270 can include tris(8-hydroxyquinoline)aluminum (Alq3), bis(2-methyl-8-quinolinolate-N1,O8)-(1,1'-biphenyl-4-ol)aluminum (BAlq), lithium quinolate (Liq), 2-biphenyl-4-yl-5-(4-tert-butylphenyl)-1,3,4- diazole (PBD), spiro-PBD, 1,3,5-tris(N-phenylbenzimidazol-2-yl)benzene (TPBi), 4,7-diphenyl-1,10-phenanthroline (Bphen), 2,9-bis(naphthalen-2-yl)4,7-diphenyl-1,10-phenanthroline (NBphen), 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), 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), 1,3,5-tris(pyridin-3-yl-phenyl)benzene (TpPyPB), 2,4,6-tris(3'-(pyridin-3-yl)biphenyl-3-yl)1,3,5-triazine (TmPPPyTz), poly[9,9-bis(3'-(N,N-dimethyl)-N-ethylammonium)-propyl)-2,7-fluorene]-alternating-2,7-(9,9-dioctylfluorene)] (PFNBr), tris(phenylquinoxaline) (TPQ), diphenyl-4-triphenylsilyl-phenylphosphine oxide (TSPO1), and combinations thereof, but not limited thereto.

[0163] The EIL 280 is disposed between the second electrode 230 and the ETL 270 and can improve the physical properties of the second electrode 230, thus increasing the lifespan of the OLED D1. In an exemplary aspect, the EIL 280 can include, but is not limited to, alkali metal halides or alkaline earth metal halides such as LiF, CsF, NaF, BaF2, etc., and / or organometallic compounds such as lithium quinolate, lithium benzoate, sodium stearate, etc.

[0164] When holes are transferred to the second electrode 230 via the EML 240 and / or electrons are transferred to the first electrode 210 via the EML 240, the OLED D1 may have a short lifetime and reduced luminous efficiency. To prevent these phenomena, the OLED D1 according to this aspect of the present disclosure may have at least one exciton blocking layer adjacent to the EML 240.

[0165] For example, the OLED D1 may include an EBL 265 between the HTL 260 and the EML 240 to control and prevent electron transfer. In one exemplary aspect, the EBL 265 may include: TCTA, tris[4-(diethylamino)phenyl]amine, N-(biphenyl-4-yl)-9,9-dimethyl-N-(4-(9-phenyl-9H-carbazol-3-yl)phenyl)-9H-fluorene-2-amine, TAPC, MTDATA, 1,3-bis(carbazol-9-yl)benzene (mCP), 3,3'-bis(N-carbazolyl)-1,1'-biphenyl (mCBP), CuPc, N,N'-bis[4-(bis(3-methylphenyl)amino)phenyl]-N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (DNTPD), TDAPB, DCDPA, 2,8-bis(9-phenyl-9H-carbazol-3-yl)dibenzothiophene, and combinations thereof, but not limited thereto.

[0166] In addition, the OLED D1 may further include an HBL 275 between the EML 240 and the ETL 270 as a second exciton blocking layer, such that holes cannot be transferred from the EML 240 to the ETL 270. In one exemplary aspect, the HBL 275 may include at least one of compounds based on diazole, compounds based on triazole, compounds based on phenanthroline, compounds based on benz oxazole, compounds based on benzothiazole, compounds based on benzimidazole, and compounds based on triazine, etc., but not limited thereto.

[0167] For example, the HBL 275 may include compounds having a relatively low HOMO energy level compared to the luminescent material in the EML 240. The HBL 275 may include Alq3, BAlq, Liq, PBD, spiro-PBD, BCP, bis-4,5-(3,5-di-3-pyridylphenyl)-2-methylpyrimidine (B3PYMPM), DPEPO, 9-(6-(9H-carbazol-9-yl)pyridin-3-yl)-9H-3,9'-bicarbazole, TSPO1, and combinations thereof, but not limited thereto.

[0168] As described above, the EML 240 in the first aspect contains a first compound H and a second compound DF having a delayed fluorescence property and a structure of Formula 1 to 12. Since an electron donor part and an electron acceptor part coexist in the organic compound having a structure of Formula 1 to 12, the dipole moment in the molecule increases and the HOMO energy level is easily separated from the LUMO energy level. Therefore, the organic compound has a delayed fluorescence property. In addition, the organic compound has a restricted molecular conformation due to the rigid structure of the fused aromatic or fused heteroaromatic part, so the energy loss in luminescence is reduced. Therefore, the organic compound can achieve luminescence with excellent luminescence efficiency and color purity.

[0169] The host for delayed fluorescence can induce the triplet excitons of the dopant to participate in the luminescence process without being quenched as non-radiative recombination. For this purpose, it is necessary to adjust the energy levels between the first compound H of the host and the second compound DF of the delayed fluorescence material.

[0170] Figure 4 is a schematic diagram showing the luminescence mechanism through the energy level band gap between luminescent materials according to an exemplary aspect of the present disclosure. As Figure 4 shown, the singlet energy level S1 of the first compound H of the host in the EML 240 H is higher than the singlet energy level S1 of the second compound DF having a delayed fluorescence property DF . Optionally, the triplet energy level T1 of the first compound H H can be higher than the triplet energy level T1 of the second compound DF DF . As an example, the triplet energy level T1 of the first compound H H can be at least about 0.2 eV, such as at least about 0.3 eV, or at least about 0.5 eV higher than the triplet energy level T1 of the second compound DF DF .

[0171] When the triplet energy level T1 of the first compound H H and / or the singlet energy level S1 H are not high enough above the triplet energy level T1 of the second compound DF DF and / or the singlet energy level S1 DF , the triplet exciton energy of the second compound DF can be reversely transferred to the triplet energy level T1 of the first compound H H . In this case, the triplet excitons reversely transferred to the triplet energy level T1 of the first compound H that cannot emit triplet excitons are quenched as non-luminescent, so that the triplet exciton energy of the second compound DF having a delayed fluorescence property cannot contribute to luminescence. The energy level band gap ΔE between the singlet energy level S1 DF and the triplet energy level T1 of the second compound DF having a delayed fluorescence property DF ​ST DF It may be equal to or less than about 0.3 eV, for example, about 0.05 eV to about 0.3 eV.

[0172] In addition, the HOMO energy level and LUMO energy level of the first compound H and the second compound DF need to be appropriately adjusted. H ) and the HOMO energy level of the second compound DF (HOMO DF ) between the energy levels (|HOMO H -HOMO DF |), or the LUMO energy level of the first compound H (LUMO H ) and the LUMO energy level (LUMO DF ) between the energy levels (|LUMO H -LUMO DF |) may be equal to or less than about 0.5 eV, for example, about 0.1 eV to about 0.5 eV.

[0173] When the EML 240 includes the first compound H, the second compound DF having delayed fluorescence characteristics, the exciton energy can be transferred from the first compound H to the second compound DF without energy loss during light emission. In this case, the first compound H of the host that can be included in the EML 240 together with the second compound having the structure of Formulae 1 to 12 does not have to have a high triplet energy level and / or a wide energy band gap. Therefore, the delay in charge injection and transfer caused by using a host having a wider energy band gap can be minimized.

[0174] In an exemplary aspect, the first compound H in the EML 240 may include 9-(3-(9H-carbazol-9-yl)phenyl)-9H-carbazole-3-carbonitrile (mCP-CN), CBP, mCBP, mCP, DPEPO, 2T-NATA, TCTA, 1,3,5-tris[(3-pyridinyl)-benzene-3-yl]benzene (TmPyPB), 2,6-bis(9H-carbazol-9-yl)pyridine (PYD-2Cz), 3',5'-bis(carbazol-9-yl)-[1,1'-biphenyl]-3,5-dicarbonitrile (DCzTPA), 4'-(9H-carbazol-9-yl)biphenyl-3,5-dicarbonitrile (pCzB-2CN), 3'-(9H-carbazol-9-yl)biphenyl-3,5-dicarbonitrile (mCzB-2CN), 4-(3-(triphenylene-2-yl)phenyl)dibenzothiophene, 9-(4-(9H-carbazol-9-yl)phenyl)-9H-3,9'-bicarbazole, 9-(3-(9H-carbazol-9-yl)phenyl)-9H-3,9'-bicarbazole, and combinations thereof, but not limited thereto. For example, the first compound may be a compound selected from Formula 13, but not limited thereto:

[0175] [Formula 13]

[0176]

[0177] When the EML 240 contains the first compound H of the host and the second compound DF of the delayed fluorescence material, the content of the second compound DF in the EML may be, but not limited to, about 10 wt% to about 70 wt%, for example about 10 wt% to about 50 wt%, for example about 20 wt% to about 50 wt%.

[0178] The organic compounds having the structures of Formulas 1 to 12 have very excellent light-emitting characteristics. Therefore, the OLED D1 containing the organic compound in the light-emitting layer 220 (for example, in the EML 240) can improve its light-emitting efficiency and light-emitting lifetime.

[0179] In another exemplary aspect, the EML 240 may further contain a third compound. Figure 5 is a schematic diagram showing the light-emitting mechanism through the energy band gap between the light-emitting materials according to another exemplary aspect of the present disclosure. The first compound H may be a host, the second compound DF (the first dopant) may be a delayed fluorescence material, and the third compound (Compound 3, the second dopant) may be a fluorescent or phosphorescent material. The first compound H and the second compound DF may be the same as those described above. When the EML 240 further contains a fluorescent or phosphorescent material and a delayed fluorescence material, the OLED D1 can also improve its light-emitting efficiency and color purity by adjusting the energy levels between these light-emitting materials.

[0180] When the EML contains only the second compound DF with delayed fluorescence characteristics, since the second compound DF can theoretically exhibit an internal quantum efficiency of 100%, the EML can achieve a high internal quantum efficiency like the phosphorescent materials in the prior art. However, due to the bond formation and conformational distortion between the electron acceptor and the electron donor in the delayed fluorescence material, additional charge transfer transitions (CT transitions) are caused within the delayed fluorescence material, and the delayed fluorescence material has various geometries. Therefore, the delayed fluorescence material shows an emission spectrum with a very wide FWHM (full width at half maximum) during the emission process, which results in poor color purity. In addition, the delayed fluorescence material utilizes both triplet exciton energy and singlet exciton energy during the emission process, while rotating various parts within its molecular structure, which leads to twisted internal charge transfer (TICT). Therefore, the emission lifetime of an OLED containing only the delayed fluorescence material may be reduced due to the weakening of the molecular bonding force between the delayed fluorescence materials.

[0181] According to this exemplary aspect, when only using the delayed fluorescence material as a dopant, in order to prevent the reduction of color purity and emission lifetime, the EML further contains a third compound FD of fluorescent or phosphorescent material. As Figure 5 shown, the triplet exciton energy of the second compound DF with delayed fluorescence characteristics is upconverted to its own singlet exciton energy through the RISC mechanism, and then the converted singlet exciton energy of the second compound DF can be transferred to the third compound FD in the same EML through the Forster Resonance Energy Transfer (FRET) mechanism to achieve super fluorescence.

[0182] When the EML 240 contains the first compound H of the host, the second compound DF of the delayed fluorescence material, and the third compound FD of the fluorescent or phosphorescent material, it is necessary to appropriately adjust the energy levels between those luminescent materials. As Figure 5 shown, the singlet energy level S1 DF of the second compound DF of the delayed fluorescence material DF and the energy level band gap ΔE ST DF between the triplet energy levels T1 H can be equal to or less than about 0.3 eV to achieve delayed fluorescence. In addition, the singlet energy level S1 DF of the first compound H of the host is higher than the singlet energy level S1 H of the second compound DF of the delayed fluorescence material. DF .

[0183] In addition, the singlet energy level S1 of the second compound DF DF is higher than the singlet energy level S1 of the third compound FD of the fluorescent or phosphorescent material FD . Alternatively, the triplet energy level T1 of the second compound DF DF can be higher than the triplet energy level T1 of the third compound FD FD .

[0184] In addition, the exciton energy should be effectively transferred from the second compound DF of the delayed fluorescence material to the third compound FD of the fluorescent or phosphorescent material to achieve super-fluorescence. As an example, a fluorescent or phosphorescent material having an absorption spectrum with a large overlapping region with the photoluminescence spectrum of the second compound DF having delayed fluorescence characteristics can be used as the third compound FD to effectively transfer the exciton energy from the second compound to the third compound.

[0185] As an example, the third compound FD emits green light. For example, the third compound FD emitting green light may have a boron-dipyrromethene (BODIPY, 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene) core, but is not limited thereto. As an example, the third compound FD may include 5,12-dimethylquinoline[2,3-b]acridine-7,14(5H,12H)-dione, 5,12-diethylquinoline[2,3-b]acridine-7,14(5H,12H)-dione, 5,12-dibutyl-3,10-difluoroquinoline[2,3-b]acridine-7,14(5H,12H)-dione, 5,12-dibutyl-3,10-bis(trifluoromethyl)quinoline[2,3-b]acridine-7,14(5H,12H)-dione, 5,12-dibutyl-2,3,9,10-tetrafluoroquinoline[2,3-b]acridine-7,14(5H,12H)-dione, 1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinoxalin-9-yl)vinyl]-4H-pyran-4-ylidene}malononitrile (DCJTB), but is not limited thereto. Alternatively, the third compound may include a phosphorescent material of a metal complex emitting green light.

[0186] When the EML 240 contains the first compound H, the second compound DF, and the third compound FD, the content of the first compound H in the EML can be greater than the content of the second compound DF, and the content of the second compound DF in the EML is greater than the content of the third compound FD. In this case, the exciton energy can be effectively transferred from the second compound DF to the third compound FD via the FRET mechanism. As an example, the contents of the first to third compounds H, DF, and FD in the EML 240 can be about 60 wt% to about 75 wt%, about 20 wt% to about 40 wt%, and about 0.1 wt% to about 5 wt%, respectively, but are not limited thereto.

[0187] Alternatively, the OLED according to the present disclosure may include multiple layers of EML. Figure 6 is a schematic cross-sectional view showing an OLED having a double-layer EML according to another exemplary aspect of the present disclosure. Figure 7 is a schematic diagram showing the light-emitting mechanism through the energy band gaps between the light-emitting materials according to another exemplary aspect of the present disclosure.

[0188] As Figure 6 shown, the OLED D2 includes a first electrode 210 and a second electrode 230 facing each other and a light-emitting layer 220A having a single light-emitting portion disposed between the first electrode 210 and the second electrode 230. The organic light-emitting display device 100 includes a red pixel region, a green pixel region, and a blue pixel region, and the OLED D2 can be disposed in the green pixel region.

[0189] In one exemplary aspect, the light-emitting layer 220A includes the EML 240A. The light-emitting layer 220A may include at least one of an HTL 260 disposed between the first electrode 210 and the EML 240A and an ETL 270 disposed between the second electrode 230 and the EML 240A. In addition, the light-emitting layer 220A may further include at least one of a HIL 250 disposed between the first electrode 210 and the HTL 260 and an EIL 280 disposed between the second electrode 230 and the ETL 270. Alternatively, the light-emitting layer 220A may further include an EBL 265 disposed between the HTL 260 and the EML 240A and / or an HBL 275 disposed between the EML 240A and the ETL 270. Except for the EML 240A in the light-emitting layer 220A, the configurations of the first electrode 210 and the second electrode 230 and the other layers are substantially the same as the corresponding electrodes and layers in the OLED D1.

[0190] EML 240A includes a first EML (EML1, lower EML, first layer) 242 and a second EML (EML2, upper EML, second layer) 244. EML1 242 is disposed between EBL 265 and HBL 275, and EML2 244 is disposed between EML1 242 and HBL 275. One of EML1 242 and EML2 244 contains a second compound (first dopant) DF of a delayed fluorescence material, and the other of EML1 242 and EML2 244 contains a fifth compound (compound 5, second dopant) FD of a fluorescent or phosphorescent material. In addition, EML1 242 and EML2 244 each contain a first compound (first host) H1 and a fourth compound (compound 4, second host) H2. In this exemplary aspect, EML1 242 contains the first compound H1 of the first host and the second compound DF of the delayed fluorescence material. EML2 244 contains the fourth compound H2 of the second host and the fifth compound FD of the fluorescent or phosphorescent material.

[0191] In EML1 242, the triplet exciton energy of the second compound DF can be upconverted to its own singlet exciton energy via the RISC mechanism. Although the second compound DF has a high internal quantum efficiency, its color purity is poor due to the wide FWHM. In contrast, the fifth compound FD of the fluorescent or phosphorescent material has an advantage in terms of color purity due to its narrow FWHM, but its internal quantum efficiency is low because its triplet excitons may not be able to participate in the luminescence process.

[0192] However, in this exemplary aspect, the singlet exciton energy and the triplet exciton energy of the second compound DF having delayed fluorescence characteristics in EML1 242 can be transferred to the fifth compound FD of the fluorescent or phosphorescent material in EML2 244 disposed adjacent to EML1 242 via the FRET mechanism (which non-radiatively transfers energy through an electric field generated by dipole-dipole interaction). Therefore, the final luminescence occurs in the fifth compound FD within EML2 244.

[0193] In other words, in EML1 242, the triplet exciton energy of the second compound DF is upconverted to its own singlet exciton energy through the RISC mechanism. Then, the converted singlet exciton energy of the second compound DF is transferred to the singlet exciton energy of the fifth compound FD in EML2 244. The fifth compound FD in EML2 244 can emit light using both the triplet exciton energy and the singlet exciton energy. Since the exciton energy generated at the second compound DF with delayed fluorescence characteristics in EML1 242 is effectively transferred from the second compound DF to the fifth compound FD of the fluorescent or phosphorescent material in EML2 244, hyperfluorescence can be achieved. In this case, substantial light emission occurs in EML2 244 containing the fifth compound FD, which is a fluorescent or phosphorescent material and has a narrow FWHM. Therefore, OLED D2 can improve its quantum efficiency and improve its color purity due to the narrow FWHM.

[0194] EML1 242 and EML2 244 each contain the first compound H1 and the fourth compound H2, respectively. The exciton energy generated at the first compound H1 and the fourth compound H2 should be transferred to the second compound DF of the delayed fluorescence material to emit light. As Figure 7 shown, the singlet energy levels S1 H1 and S1 H2 of each of the first compound H1 and the fourth compound H2 are higher than the singlet energy level S1 DF of the second compound DF of the delayed fluorescence material. Alternatively, the triplet energy levels T1 H1 and T1 H2 of each of the first compound H1 and the fourth compound H2 can be higher than the triplet energy level T1 DF of the second compound DF. As an example, the triplet energy levels T1 H1 and T1 H2 of each of the first compound H1 and the fourth compound H2 can be at least about 0.2 eV higher than the triplet energy level T1 DF of the second compound DF, such as at least about 0.3 eV, or at least about 0.5 eV.

[0195] In addition, the singlet energy level S1 H2 of the fourth compound H2 is higher than the singlet energy level S1 FD of the fifth compound FD. In this case, the singlet exciton energy generated at the fourth compound H2 can be transferred to the singlet energy level S1 FD of the fifth compound FD. Optionally, the triplet energy level T1 H2 of the fourth compound H2 can be higher than the triplet energy level T1 FD of the fifth compound FD.

[0196] In addition, the EML 240A needs to achieve high luminous efficiency and color purity, and effectively transfer the exciton energy from the second compound DF in the EML1 242 (which is converted into an ICT complex state through the RISC mechanism) to the fifth compound FD of the fluorescent or phosphorescent material in the EML2 244. To achieve such an OLED D2, the singlet energy level S1 of the second compound DF DF is higher than the singlet energy level S1 of the fifth compound FD of the fluorescent or phosphorescent material FD . Optionally, the triplet energy level T1 of the second compound DF DF can be higher than the triplet energy level T1 of the fifth compound FD FD .

[0197] In addition, the energy band gap (|HOMO H - HOMO DF |) between the HOMO energy level (HOMO H ) of the first compound H1 and / or the fourth compound H2 and the HOMO energy level (HOMO DF ) of the second compound DF, or the energy band gap (|LUMO H - LUMO DF |) between the LUMO energy level (LUMO H ) of the first compound H1 and / or the fourth compound H2 and the LUMO energy level (LUMO DF ) of the second compound DF can be equal to or less than about 0.5 eV. When the luminescent material does not meet the required energy levels as described above, the exciton energy is quenched at the second compound DF and the fifth compound FD, or the exciton energy cannot be effectively transferred from the first compound H1 and the fourth compound H2 to the second compound DF and the fifth compound FD, such that the OLED D2 may have a reduced quantum efficiency.

[0198] The first compound H1 and the fourth compound H2 can be the same as or different from each other. For example, the first compound H1 and the fourth compound H2 can each independently be the same as the first compound H as described above. The second compound DF can be an organic compound having a structure of Formula 1 to 12. The fifth compound FD can have a narrow FWHM and an absorption spectrum that has a large overlapping region with the emission spectrum of the second compound DF. The fifth compound FD can be a fluorescent or phosphorescent material that emits green light. For example, the fifth compound FD can be the fluorescent or phosphorescent material of the third compound as described above.

[0199] In an exemplary aspect, the contents of the first compound H1 and the fourth compound H2 in the EML1 242 and the EML2 244 may be greater than or equal to the contents of the second compound DF and the fifth compound FD in the same layer. Additionally, the content of the second compound DF in the EML1 242 may be greater than the content of the fifth compound FD in the EML2 244. In this case, the exciton energy can be effectively transferred from the second compound DF to the fifth compound FD via the FRET mechanism. As an example, the content of the second compound DF in the EML1 242 may be about 1 wt% to about 70 wt%, about 10 wt% to about 50 wt%, or about 20 wt% to about 50 wt%, but is not limited thereto. Additionally, the content of the fifth compound FD in the EML2 244 may be about 1 wt% to about 10 wt%, or about 1 wt% to about 5 wt%.

[0200] In an exemplary aspect, when the EML2 244 is disposed adjacent to the HBL 275, the fourth compound H2 in the EML2 244 may be the same material as the HBL 275. In this case, the EML2 244 may have a hole blocking function as well as a light emitting function. In other words, the EML2 244 may act as a buffer layer for blocking holes. In one aspect, in the case where the EML2 244 can be a hole blocking layer and a light emitting material layer, the HBL 275 may be omitted.

[0201] In another exemplary aspect, when the EML2 244 is disposed adjacent to the EBL 265, the fourth compound H2 may be the same material as the EBL 265. In this case, the EML2 244 may have an electron blocking function as well as a light emitting function. In other words, the EML2 244 may act as a buffer layer for blocking electrons. In one aspect, in the case where the EML2 244 can be an electron blocking layer and a light emitting material layer, the EBL 265 may be omitted.

[0202] An OLED having a three-layer EML will be described. Figure 8 is a schematic cross-sectional view of an OLED having a three-layer EML according to another exemplary aspect of the present disclosure. Figure 9 is a schematic diagram showing a light emitting mechanism through the energy level bandgap between light emitting materials according to another exemplary aspect of the present disclosure.

[0203] As Figure 8 shown, the OLED D3 includes a first electrode 210 and a second electrode 230 facing each other and a light emitting layer 220B having a single light emitting portion disposed between the first electrode 210 and the second electrode 230. The organic light emitting display device 100( Figure 2)It includes a red pixel region, a green pixel region, and a blue pixel region, and the OLED D3 can be disposed in the green pixel region.

[0204] In one exemplary aspect, the light-emitting layer 220B includes three layers of EML 240B. The light-emitting layer 220B may include at least one of an HTL 260 disposed between the first electrode 210 and the EML 240B and an ETL 270 disposed between the second electrode 230 and the EML 240B. In addition, the light-emitting layer 220B may further include at least one of an HIL 250 disposed between the first electrode 210 and the HTL 260 and an EIL 280 disposed between the second electrode 230 and the ETL 270. Alternatively, the light-emitting layer 220B may further include an EBL 265 disposed between the HTL 260 and the EML 240B and / or an HBL 275 disposed between the EML 240B and the ETL 270. Except for the EML 240B in the light-emitting layer 220B, the configurations of the first electrode 210 and the second electrode 230 and other layers are substantially the same as the corresponding electrodes and layers in the OLEDs D1 and D2.

[0205] The EML 240B includes a first EML (EML1, middle EML, first layer) 242, a second EML (EML2, lower EML, second layer) 244, and a third EML (EML3, upper EML, third layer) 246. The EML1 242 is disposed between the EBL 265 and the HBL 275, the EML2 244 is disposed between the EBL 265 and the EML1 242, and the EML3 246 is disposed between the EML1 242 and the HBL 275.

[0206] The EML1 242 contains a second compound (first dopant) DF of a delayed fluorescence material. The EML2 244 and the EML3 246 each contain a fifth compound (second dopant) FD1 and a seventh compound (compound 7, third dopant) FD2 that may be a fluorescent or phosphorescent material, respectively. In addition, each of the EML1 242, the EML2 244, and the EML3 246 further contains a first compound (host 1) H1, a fourth compound (host 2) H2, and a sixth compound (compound 6, host 3) H3 that may be a first host to a third host, respectively.

[0207] According to this aspect, the singlet energy and triplet energy of the second compound DF of the delayed fluorescence material in EML1 242 can be transferred to the fifth compound FD1 and the seventh compound FD2 of the fluorescent or phosphorescent material respectively included in EML2 244 and EML3 246 arranged adjacent to EML1 242 through the FRET mechanism. Therefore, the final emission occurs in the fifth compound FD1 and the seventh compound FD2 in EML2 244 and EML3 246.

[0208] The triplet exciton energy of the second compound DF in EML1 242 is upconverted to its own singlet exciton energy through the RISC mechanism, and then the singlet exciton energy of the second compound DF is transferred to the singlet exciton energy of the fifth compound FD1 and the seventh compound FD2 in EML2 244 and EML3 246 because the singlet energy level S1 of the second compound DF DF is higher than the singlet energy levels S1 of the fifth compound FD1 and the seventh compound FD2 FD1 and S1 FD2 of each of them ( Figure 9 ). The singlet exciton energy of the second compound DF in EML1 242 is transferred to the fifth compound FD1 and the seventh compound FD2 in EML2 244 and EML3 246 arranged adjacent to EML1 242 through the FRET mechanism.

[0209] The fifth compound FD1 and the seventh compound FD2 in EML2 244 and EML3 246 can emit light using the singlet exciton energy and triplet exciton energy derived from the second compound DF. Compared with the second compound DF, each of the fifth compound FD1 and the seventh compound FD2 can have a narrower FWHM. Since the exciton energy generated at the second compound DF with delayed fluorescence characteristics in EML1 242 is transferred to the fifth compound FD1 and the seventh compound FD2 in EML2 244 and EML3 246, super fluorescence can be achieved. In particular, each of the fifth compound FD1 and the seventh compound FD2 can have an emission spectrum with a large overlapping region with the absorption spectrum of the second compound DF, so that the exciton energy of the second compound DF can be effectively transferred to each of the fifth compound FD1 and the seventh compound FD2. In this case, substantial emission occurs in EML2 244 and EML3 246.

[0210] To achieve effective emission in EML 240B, it is necessary to appropriately adjust the energy levels between the luminescent materials in EML1 242, EML2 244 and EML3 246. As Figure 9As shown, the singlet energy levels S1 of the first, fourth, and sixth compounds H1, H2, and H3, which can be the first to third main bodies respectively H1 , S1 H2 and S1 H3 each of which is higher than the singlet energy level S1 DF . Alternatively, the triplet energy levels T1 of the first, fourth, and sixth compounds H1, H2, and H3 H1 , T1 H2 and T1 H3 each of which can be higher than the triplet energy level T1 of the second compound DF DF .

[0211] In addition, the EML 240B needs to achieve high luminous efficiency and color purity, and effectively transfer the exciton energy from the second compound DF in the EML1 242 (which is converted to the ICT composite state through the RISC mechanism) to the fifth compound FD1 and the seventh compound FD2, which are fluorescent or phosphorescent materials respectively, in the EML2 244 and the EML3 246. To achieve such an OLED D3, the singlet energy level S1 of the second compound DF DF is higher than the singlet energy levels S1 of the fifth compound FD1 and the seventh compound FD2, which are fluorescent or phosphorescent materials FD1 and S1 FD2 each of which. Alternatively, the triplet energy level T1 of the second compound DF DF can be higher than the triplet energy levels T1 of the fifth compound FD1 and the seventh compound FD2 FD1 and T1 FD2 each of which.

[0212] In addition, to achieve efficient light emission, the exciton energy transferred from the second compound DF to each of the fifth compound FD1 and the seventh compound FD2 should not be transferred to the fourth compound H2 and the sixth compound H3. For this purpose, the singlet energy levels S1 of the fourth compound H2 and the sixth compound H3 H2 and S1 H3 each of which is higher than the excited singlet energy levels S1 of the fifth compound FD1 and the seventh compound FD2 FD1 and S1 FD2 each of which. Alternatively, the triplet energy levels T1 of the fourth compound H2 and the sixth compound H3 H2 and T1 H3 each of which can be higher than the triplet energy levels T1 of the fifth compound FD1 and the seventh compound FD2 FD1 and T1 FD2 each of which.

[0213] As described above, EML1 242, EML2 244, and EML3 246 may each contain the first, fourth, and sixth compounds H1, H2, and H3, respectively. For example, the first, fourth, and sixth compounds H1, H2, and H3 may each be the same as or different from one another. For example, the first, fourth, and sixth compounds H1, H2, and H3 may each independently be the same as the first compound H described above. The second compound DF of the delayed fluorescence material may be an organic compound having a structure of Formulas 1 to 12. In addition, each of the fifth compound FD1 and the seventh compound FD2 may be the same as the third compound FD of the fluorescent or phosphorescent material.

[0214] In one exemplary aspect, the content of the second compound DF in EML1 242 may be greater than each of the contents of the fifth compound FD1 and the seventh compound FD2 in EML2 244 and EML3 246, respectively. In this case, the exciton energy may be effectively transferred from the second compound DF to the fifth compound FD1 and the seventh compound FD2 via the FRET mechanism. As an example, the content of the second compound DF in EML1 242 may be about 1 wt% to about 70 wt%, or about 10 wt% to about 50 wt%, or about 20 wt% to about 50 wt%, but is not limited thereto. In addition, the contents of the fifth compound FD1 and the seventh compound FD2 in EML2 244 and EML3 246 may each be about 1 wt% to about 10 wt%, or about 1 wt% to about 5 wt%.

[0215] In one exemplary aspect, when EML2 244 is disposed adjacent to EBL 265, the fourth compound H2 in EML2 244 may be the same material as EBL 265. In this case, EML2 244 may have an electron blocking function as well as a light emitting function. In other words, EML2 244 may act as a buffer layer for blocking electrons. In one aspect, when EML2 244 may be an electron blocking layer and a light emitting material layer, EBL 265 may be omitted.

[0216] In another exemplary aspect, when EML3 246 is disposed adjacent to HBL 275, the sixth compound H3 in EML3 246 may be the same material as HBL 275. In this case, EML3 246 may have a hole blocking function as well as a light emitting function. In other words, EML3 246 may act as a buffer layer for blocking holes. In one aspect, when EML3 246 may be a hole blocking layer and a light emitting material layer, HBL 275 may be omitted.

[0217] In yet another exemplary aspect, the fourth compound H2 in the EML2 244 can be the same material as the EBL 265, and the sixth compound H3 in the EML3 246 can be the same material as the HBL 275. In this aspect, the EML2 244 can have an electron blocking function and a light emitting function, and the EML3 246 can have a hole blocking function and a light emitting function. In other words, each of the EML2 244 and the EML3 246 can serve as a buffer layer for blocking electrons or holes, respectively. In one aspect, when the EML2 244 can be an electron blocking layer and a light emitting material layer, and the EML3 246 can be a hole blocking layer and a light emitting material layer, the EBL 265 and the HBL 275 can be omitted.

[0218] In another aspect, the OLED can include a plurality of light emitting portions. Figure 10 is a schematic cross-sectional view of an OLED showing yet another exemplary aspect according to the present disclosure.

[0219] As Figure 10 shown, the OLED D4 includes a first electrode 210 and a second electrode 230 facing each other, and a light emitting layer 220C having two light emitting portions disposed between the first electrode 210 and the second electrode 230. The organic light emitting display device 100( Figure 2 ) includes a red pixel region, a green pixel region, and a blue pixel region, and the OLED D4 can be disposed in the green pixel region. The first electrode 210 can be an anode, and the second electrode 230 can be a cathode.

[0220] The light emitting layer 220C includes a first light emitting portion 320 and a second light emitting portion 420. The first light emitting portion 320 includes a first EML (EML1) 340, and the second light emitting portion 420 includes a second EML (EML2) 440. In addition, the light emitting layer 220C can further include a charge generation layer (CGL) 380 disposed between the first light emitting portion 320 and the second light emitting portion 420.

[0221] The CGL 380 is disposed between the first light emitting portion 320 and the second light emitting portion 420 such that the first light emitting portion 320, the CGL 380, and the second light emitting portion 420 are sequentially disposed on the first electrode 210. In other words, the first light emitting portion 320 is disposed between the first electrode 210 and the CGL 380, and the second light emitting portion 420 is disposed between the second electrode 230 and the CGL 380.

[0222] The first light-emitting part 320 includes EML1 340. The first light-emitting part 320 may further include at least one of a first HTL (HTL1) 360 disposed between the first electrode 210 and EML1 340, a HIL 350 disposed between the first electrode 210 and HTL1 360, and a first ETL (ETL1) 370 disposed between EML1 340 and CGL 380. Alternatively, the first light-emitting part 320 may further include a first EBL (EBL1) 365 disposed between HTL1 360 and EML1 340 and / or a first HBL (HBL1) 375 disposed between EML1 340 and ETL1 370.

[0223] The second light-emitting part 420 includes EML2 440. The second light-emitting part 420 may further include at least one of a second HTL (HTL2) 460 disposed between CGL 380 and EML2 440, a second ETL (ETL2) 470 disposed between EML2 440 and the second electrode 230, and an EIL 480 disposed between ETL2 470 and the second electrode 230. Alternatively, the second light-emitting part 420 may further include a second EBL (EBL2) 465 disposed between HTL2 460 and EML2 440 and / or a second HBL (HBL2) 475 disposed between EML2 440 and ETL2 470.

[0224] CGL 380 is disposed between the first light-emitting part 320 and the second light-emitting part 420. The first light-emitting part 320 and the second light-emitting part 420 are connected via CGL 380. CGL 380 may be a PN junction CGL that connects an N-type CGL (N-CGL) 382 and a P-type CGL (P-CGL) 384.

[0225] N-CGL 382 is disposed between ETL1 370 and HTL2 460, and P-CGL 384 is disposed between N-CGL 382 and HTL2 460. N-CGL 382 transports electrons to EML1 340 of the first light-emitting part 320, and P-CGL 384 transports holes to EML2 440 of the second light-emitting part 420.

[0226] In this aspect, each of EML1 340 and EML2 440 may be a green light-emitting material layer. For example, at least one of EML1 340 and EML2 440 contains a first compound H of the host, a second compound DF of the delayed fluorescence material, and an optional third compound FD of the fluorescent or phosphorescent material.

[0227] When the EML1 340 contains the first compound H, the second compound DF, and the third compound FD, the content of the first compound H can be greater than the content of the second compound DF, and the content of the second compound DF can be greater than the content of the third compound FD. In this case, the exciton energy can be effectively transferred from the second compound DF to the third compound FD. As an example, the contents of the first to third compounds H, DF, and FD in the EML1 340 can be respectively about 60 wt% to about 75 wt%, about 20 wt% to about 40 wt%, and about 0.1 wt% to about 5 wt%, but not limited thereto.

[0228] In one exemplary aspect, the EML2 440 can contain the first compound H of the host, the second compound DF of the delayed fluorescence material, and the third compound FD of the optional fluorescent or phosphorescent material. Alternatively, the EML2 440 can contain additional compounds different from at least one of the second compound DF and the third compound FD in the EML1 340, so the EML2 440 can emit light different from the light emitted from the EML1 340, or can have a different luminous efficiency from the luminous efficiency of the EML1 340.

[0229] In Figure 10 , the EML1 340 and the EML2 440 each have a single-layer structure. Alternatively, the EML1 340 and the EML2 440 each containing the first to third compounds H, DF, and FD can respectively have a bilayer structure ( Figure 6 ) or a trilayer structure ( Figure 8 ).

[0230] In the OLED D4, the singlet exciton energy of the second compound DF of the delayed fluorescence material is transferred to the third compound FD of the fluorescent or phosphorescent material, and the final emission occurs at the third compound FD. Therefore, the OLED D4 can have excellent luminous efficiency and color purity. In addition, the OLED D4 has a double-stack structure of the green light-emitting material layer, and the OLED D4 can improve its color perception or optimize its luminous efficiency.

[0231] Figure 11 is a schematic cross-sectional view showing an organic light-emitting display device according to another exemplary aspect of the present disclosure. As Figure 11 shown, the organic light-emitting display device 500 includes a substrate 510 defining first to third pixel regions P1, P2, and P3; a thin-film transistor Tr disposed above the substrate 510, and an OLED D disposed above the thin-film transistor Tr and connected to the thin-film transistor Tr. As an example, the first pixel region P1 can be a green pixel region, the second pixel region P2 can be a red pixel region, and the third pixel region P3 can be a blue pixel region.

[0232] The substrate 510 may be a glass substrate or a flexible substrate. For example, the flexible substrate may be any one of a PI substrate, a PES substrate, a PEN substrate, a PET substrate, and a PC substrate.

[0233] The buffer layer 512 is disposed above the substrate 510, and the thin film transistor Tr is disposed above the buffer layer 512. The buffer layer 512 may be omitted. As Figure 2 shown, the thin film transistor Tr includes a semiconductor layer, a gate electrode, a source electrode, and a drain electrode and serves as a driving element.

[0234] The passivation layer 550 is disposed above the thin film transistor Tr. The passivation layer 550 has a flat top surface and a drain contact hole 552 that exposes the drain electrode of the thin film transistor Tr.

[0235] The OLED D is disposed above the passivation layer 550, and includes a first electrode 610 connected to the drain electrode of the thin film transistor Tr, and a light emitting layer 620 and a second electrode 630 sequentially disposed on the first electrode 610, respectively. The OLED D is disposed in each of the first to third pixel regions P1, P2, and P3 and emits different lights in each pixel region. For example, the OLED D in the first pixel region P1 may emit green light, the OLED D in the second pixel region P2 may emit red light, and the OLED D in the third pixel region P3 may emit blue light.

[0236] The first electrode 610 is formed for each of the first to third pixel regions P1, P2, and P3, respectively, and the second electrode 630 corresponds to the first to third pixel regions P1, P2, and P3 and is integrally formed.

[0237] The first electrode 610 may be one of an anode and a cathode, and the second electrode 630 may be the other of the anode and the cathode. In addition, one of the first electrode 610 and the second electrode 630 is a transmissive (or semi-transmissive) electrode, and the other of the first electrode 610 and the second electrode 630 is a reflective electrode.

[0238] For example, the first electrode 610 may be an anode and may include a conductive material having a relatively high work function value, for example, a transparent conductive oxide layer of a transparent conductive oxide (TCO). The second electrode 630 may be a cathode and may include a conductive material having a relatively low work function value, for example, a metal material layer of a low-resistance metal. For example, the first electrode 610 may include any one of ITO, IZO, ITZO, SnO, ZnO, ICO, and AZO, and the second electrode 630 may include Al, Mg, Ca, Ag, their alloys, or their combinations.

[0239] When the organic light emitting display device 500 is a bottom emission type, the first electrode 610 may have a single layer structure of a transparent conductive oxide layer.

[0240] Alternatively, when the organic light emitting display device 500 is a top emission type, a reflective electrode or a reflective layer may be provided under the first electrode 610. For example, the reflective electrode or the reflective layer may include Ag or an APC alloy, but is not limited thereto. In the top emission type OLED D, the first electrode 610 may have a three-layer structure of ITO / Ag / ITO or ITO / APC / ITO. In addition, the second electrode 630 is thin to have light transmission (or semi-transmission) characteristics.

[0241] The bank layer 560 is provided on the passivation layer 550 to cover the edge of the first electrode 610. The bank layer 560 exposes the center of the first electrode 610 corresponding to each of the first to third pixel regions P1, P2, and P3, respectively.

[0242] The light emitting layer 620 is provided on the first electrode 610. In one exemplary aspect, the light emitting layer 620 may have a single layer structure of an EML. Alternatively, the light emitting layer 620 may include at least one of an HIL, an HTL, and an EBL sequentially provided between the first electrode 610 and the EML, and / or at least one of an HBL, an ETL, and an EIL sequentially provided between the EML and the second electrode 630.

[0243] In one exemplary aspect, the EML of the light emitting layer 620 in the first pixel region P1 of the green pixel region may include a first compound H of a host, a second compound DF of a delayed fluorescence material, and an optional third compound FD of a fluorescent or phosphorescent material.

[0244] The encapsulation film 570 is provided above the second electrode 630 to prevent external moisture from penetrating into the OLED D. The encapsulation film 570 may have a three-layer structure of a first inorganic insulating film, an organic insulating film, and a second inorganic insulating film, but is not limited thereto.

[0245] In addition, the organic light emitting display device 500 may have a polarizer to reduce external light reflection. For example, the polarizer may be a circular polarizer. When the organic light emitting display device 500 is a bottom emission type, the polarizer may be provided under the substrate 510. Alternatively, when the organic light emitting display device 500 is a top emission type, the polarizer may be provided above the encapsulation film 570.

[0246] Figure 12 is a schematic cross-sectional view of an OLED showing another exemplary aspect according to the present disclosure. As Figure 12As shown, the OLED D5 includes a first electrode 610, a second electrode 630 facing the first electrode 610, and a light-emitting layer 620 disposed between the first electrode 610 and the second electrode 630.

[0247] The first electrode 610 can be an anode, and the second electrode 630 can be a cathode. As an example, the first electrode 610 can be a reflective electrode, and the second electrode 630 can be a transmissive (or semi-transmissive) electrode.

[0248] The light-emitting layer 620 includes an EML 640. The light-emitting layer 620 can include at least one of an HTL 660 disposed between the first electrode 610 and the EML 640 and an ETL 670 disposed between the second electrode 630 and the EML 640. In addition, the light-emitting layer 620 can also include at least one of a HIL 650 disposed between the first electrode 610 and the HTL 660 and an EIL 680 disposed between the second electrode 630 and the ETL 670. Alternatively, the light-emitting layer 620 can also include an EBL 665 disposed between the HTL 660 and the EML 640 and / or a HBL 675 disposed between the EML 640 and the ETL 670.

[0249] In addition, the light-emitting layer 620 can also include an auxiliary hole transport layer (auxiliary HTL) 662 disposed between the HTL 660 and the EBL 665. The auxiliary HTL 662 can include a first auxiliary HTL 662a located in the first pixel region P1, a second auxiliary HTL 662b located in the second pixel region P2, and a third auxiliary HTL 662c located in the third pixel region P3.

[0250] The first auxiliary HTL 662a has a first thickness, the second auxiliary HTL 662b has a second thickness, and the third auxiliary HTL 662c has a third thickness. The first thickness is less than the second thickness and greater than the third thickness. Therefore, the OLED D5 has a microcavity structure.

[0251] Since the first to third auxiliary HTLs 662a, 662b, and 662c have different thicknesses from each other, the distance between the first electrode 610 and the second electrode 630 in the first pixel region P1 that emits light in the first wavelength range (green light) is less than the distance between the first electrode 610 and the second electrode 630 in the second pixel region P2 that emits light in the second wavelength range (red light), but greater than the distance between the first electrode 610 and the second electrode 630 in the third pixel region P3 that emits light in the third wavelength range (blue light). Therefore, the OLED D5 has improved luminous efficiency.

[0252] In Figure 12Among them, the third auxiliary HTL 662c is located in the third pixel region P3. Alternatively, the OLED D5 can implement a microcavity structure without the third auxiliary HTL 662c. In addition, a cover layer 580 can be disposed above the second electrode 630 to improve the out-coupling of the light emitted from the OLED D5.

[0253] The EML 640 includes a first EML (EML1) 642 located in the first pixel region P1, a second EML (EML2) 644 located in the second pixel region P2, and a third EML (EML3) 646 located in the third pixel region P3. The EML1 642, EML2 644, and EML3 646 can each be a green EML, a red EML, and a blue EML, respectively.

[0254] In an exemplary aspect, the EML1 642 located in the first pixel region P1 may include a first compound H as a host, a second compound DF as a delayed fluorescence material, and optionally a third compound FD as a fluorescent or phosphorescent material. The EML1 642 may have a single-layer structure, a bilayer structure ( Figure 6 ) or a triple-layer structure ( Figure 8 ).

[0255] In an exemplary aspect, in the EML1 642, the content of the first compound H may be greater than the content of the second compound DF, and the content of the second compound DF may be greater than the content of the third compound FD. In this case, the exciton energy can be effectively transferred from the second compound DF to the third compound FD. As an example, the contents of the first to third compounds H, DF, and FD in the EML1 642 may each be about 60 wt% to about 75 wt%, about 20 wt% to about 40 wt%, and about 0.1 wt% to about 5 wt%, but are not limited thereto.

[0256] The EML2 644 in the second pixel region P2 may include a host and a red dopant, and the EML3 646 in the third pixel region P3 may include a host and a blue dopant. For example, the host in each of the EML2 644 and EML3 646 may include the first compound H, and the red dopant and the blue dopant may each include at least one of a red phosphorescent material or a blue phosphorescent material, a red fluorescent material or a blue fluorescent material, and a red delayed fluorescence material or a blue delayed fluorescence material.

[0257] For example, the host in EML2 644 may include 9,9'-biphenyl-9H,9'H-3,3'-bicarbazole (BCzPh), CBP, 1,3,5-tris(carbazol-9-yl)benzene (TCP), TCTA, 4,4'-bis(carbazol-9-yl)-2,2'-dimethylbiphenyl (CDBP), 2,7-bis(carbazol-9-yl)-9,9-dimethylfluorene (DMFL-CBP), 2,2',7,7'-tetrakis(carbazol-9-yl)-9,9-spirobifluorene (spiro-CBP), DPEPO, 4'-(9H-carbazol-9-yl)biphenyl-3,5-dicarbonitrile (PCzB-2CN), 3'-(9H-carbazol-9-yl)biphenyl-3,5-dicarbonitrile (mCzB-2CN), 3,6-bis(carbazol-9-yl)-9-(2-ethyl-hexyl)-9H-carbazole (TCz1), Bepp2, bis(10-hydroxybenzo[h]quinolinato)beryllium (Bebq2), 1,3,5-tris(1-pyrenyl)benzene (TPB3), and combinations thereof, but not limited thereto.

[0258] The red dopants in EML2 644 may include, but are not limited to, red phosphorescent dopants and / or red fluorescent dopants, such as iridium(III) bis(2-(4,6-dimethyl)phenylquinoline)(2,2,6,6-tetramethylheptane-3,5-dionate), iridium(III) bis[2-(4-n-hexylphenyl)quinoline](acetylacetonate) (Hex-Ir(phq)2(acac)), iridium(III) tris[2-(4-n-hexylphenyl)quinoline] (Hex-Ir(phq)3), iridium(III) tris[2-phenyl-4-methylquinoline] (Ir(Mphq)3), iridium(III) bis(2-phenylquinoline)(2,2,6,6-tetramethylheptane-3,5-dionate) (Ir(dpm)PQ2), iridium(III) bis(phenylisoquinoline)(2,2,6,6-tetramethylheptane-3,5-dionate) (Ir(dpm)(piq)2), iridium(III) bis[(4-n-hexylphenyl)isoquinoline](acetylacetonate) (Hex-Ir(piq)2(acac)), iridium(III) tris[2-(4-n-hexylphenyl)quinoline] (Hex-Ir(piq)3), iridium(III) tris(2-(3-methylphenyl)-7-methyl-quinolinato) (Ir(dmpq)3), iridium(III) bis[2-(2-methylphenyl)-7-methyl-quinoline](acetylacetonate) (Ir(dmpq)2(acac)), iridium(III) bis[2-(3,5-dimethylphenyl)-4-methyl-quinoline(acetylacetonate)) (Ir(mphmq)2(acac)), europium(III) tris(dibenzoylmethane)mono(1,10-phenanthroline) (Eu(dbm)3(phen)), and combinations thereof.

[0259] The host in EML3 646 may include mCP, mCP-CN, mCBP, CBP-CN, 9-(3-(9H-carbazol-9-yl)phenyl)-3-(diphenylphosphoryl)-9H-carbazole (mCPPO1), 3,5-bis(9H-carbazol-9-yl)biphenyl (Ph-mCP), TSPO1, 9-(3'-(9H-carbazol-9-yl)-[1,1'-biphenyl]-3-yl)-9H-pyrido[2,3-b]indole (CzBPCb), bis(2-methylphenyl)diphenylsilane (UGH-1), 1,4-bis(triphenylsilyl)benzene (UGH-2), 1,3-bis(triphenylsilyl)benzene (UGH-3), 9,9-spirobifluorene-2-yl-diphenylphosphine oxide (SPPO1), 9,9'-(5-(triphenylsilyl)-1,3-phenylene)bis(9H-carbazole) (SimCP), and combinations thereof, but not limited thereto.

[0260] The blue dopant in EML3 646 may include, but is not limited to, blue phosphorescent dopants and / or blue fluorescent dopants, such as perylene, 4,4'-bis[4-(di-p-tolylamino)styryl]biphenyl (DPAVBi), 4-(di-p-tolylamino)-4-4'-[(di-p-tolylamino)styryl]styrene (DPAVB), 4,4'-bis[4-(diphenylamino)styryl]biphenyl (BDAVBi), 2,7-bis(4-diphenylaminostyryl)-9,9-spirobifluorene (spiro-DPVBi), [1,4-bis[2-[4-[N,N-bis(p-tolyl)amino]phenyl]vinyl]benzene (DSB), 1-4-di-[4-(N,N-diphenyl)aminostyryl]benzene (DSA), 2,5,8,11-tetra-tert-butylperylene (TBPe), bis(2-hydroxyphenyl)pyrido)beryllium (Bepp2), 9-(9-phenylcarbazol-3-yl)-10-(naphthalen-1-yl)anthracene (PCAN), mer-tris(1-phenyl-3-methylimidazolin-2-ylidene-C,C(2)')iridium(III) (mer-Ir(pmi)3), fac-tris(1,3-diphenyl-benzimidazolin-2-ylidene-C,C(2)')iridium(III) (fac-Ir(dpbic)3), bis(3,4,5-trifluoro-2-(2-pyridyl)phenyl-(2-carboxypyridyl)iridium(III) (Ir(tfpd)2pic), tris(2-(4,6-difluorophenyl)pyridine))iridium(III) (Ir(Fppy)3), bis[2-(4,6-difluorophenyl)pyridine-C 2 ,N](pyridinecarbonyl)iridium(III) (FIrpic), and combinations thereof.

[0261] The OLED D5 emits green, red, and blue light in the first pixel region P1, the second pixel region P2, and the third pixel region P3, respectively, such that the organic light-emitting display device 500 ( Figure 11 ) can implement a full-color image.

[0262] The organic light-emitting display device 500 may further include a color filter layer corresponding to the first pixel region P1, the second pixel region P2, and the third pixel region P3 to improve the color purity of the light emitted from the OLED D. As an example, the color filter layer may include a first color filter layer (green color filter layer) corresponding to the first pixel region P1, a second color filter layer (red color filter layer) corresponding to the second pixel region P2, and a third color filter layer (blue color filter layer) corresponding to the third pixel region P3.

[0263] When the organic light-emitting display device 500 is a bottom-emitting type, the color filter layer may be disposed between the OLED D and the substrate 510. Alternatively, when the organic light-emitting display device 500 is a top-emitting type, the color filter layer may be disposed above the OLED D.

[0264] Figure 13 is a schematic cross-sectional view of an organic light-emitting display device showing another exemplary aspect according to the present disclosure. As Figure 13 shown, the organic light-emitting display device 1000 includes: a substrate 1010 defining a first pixel region P1, a second pixel region P2, and a third pixel region P3; a thin-film transistor Tr disposed above the substrate 1010; an OLED D disposed above the thin-film transistor Tr and connected to the thin-film transistor Tr; and a color filter layer 1020 corresponding to the first to third pixel regions P1, P2, and P3. As an example, the first pixel region P1 may be a green pixel region, the second pixel region P2 may be a red pixel region, and the third pixel region P3 may be a blue pixel region.

[0265] The substrate 1010 may be a glass substrate or a flexible substrate. For example, the flexible substrate may be any one of a PI substrate, a PES substrate, a PEN substrate, a PET substrate, and a PC substrate. The thin-film transistor Tr is located above the substrate 1010. Alternatively, a buffer layer may be disposed above the substrate 1010, and the thin-film transistor Tr may be disposed above the buffer layer. As Figure 2 shown, the thin-film transistor Tr includes a semiconductor layer, a gate electrode, a source electrode, and a drain electrode and serves as a driving element.

[0266] The color filter layer 1020 is located above the substrate 1010. As an example, the color filter layer 1020 may include a first color filter layer 1022 corresponding to the first pixel region P1, a second color filter layer 1024 corresponding to the second pixel region P2, and a third color filter layer 1026 corresponding to the third pixel region P3. The first color filter layer 1022 may be a green color filter layer, the second color filter layer 1024 may be a red color filter layer, and the third color filter layer 1026 may be a blue color filter layer. For example, the first color filter layer 1022 may contain at least one of a green dye or a blue pigment, the second color filter layer 1024 may contain at least one of a red dye or a green pigment, and the third color filter layer 1026 may contain at least one of a blue dye or a red pigment.

[0267] The passivation layer 1050 is disposed above the thin film transistor Tr and the color filter layer 1020. The passivation layer 1050 has a flat top surface and a drain contact hole 1052 that exposes the drain electrode of the thin film transistor Tr.

[0268] The OLED D is disposed above the passivation layer 1050 and corresponds to the color filter layer 1020. The OLED D includes a first electrode 1110 connected to the drain electrode of the thin film transistor Tr, a light emitting layer 1120 and a second electrode 1130 that are sequentially disposed on the first electrode 1110. The OLED D emits white light in the first to third pixel regions P1, P2, and P3.

[0269] The first electrode 1110 is formed separately for each of the first to third pixel regions P1, P2, and P3, and the second electrode 1130 corresponds to the first to third pixel regions P1, P2, and P3 and is integrally formed.

[0270] The first electrode 1110 may be one of an anode and a cathode, and the second electrode 1130 may be the other of the anode and the cathode. In addition, the first electrode 1110 may be a transmissive (or semi-transmissive) electrode, and the second electrode 1130 may be a reflective electrode.

[0271] For example, the first electrode 1110 may be an anode and may include a conductive material having a relatively high work function value, such as a transparent conductive oxide layer of a transparent conductive oxide (TCO). The second electrode 1130 may be a cathode and may include a conductive material having a relatively low work function value, such as a metal material layer of a low-resistance metal. For example, the transparent conductive oxide layer of the first electrode 1110 may include any one of ITO, IZO, ITZO, SnO, ZnO, ICO, and AZO, and the second electrode 1130 may include Al, Mg, Ca, Ag, an alloy thereof (such as Mg-Ag), or a combination thereof.

[0272] The light-emitting layer 1120 is disposed on the first electrode 1110. The light-emitting layer 1120 includes at least two light-emitting portions that emit different colors. Each of the light-emitting portions may have a single-layer structure of EML. Alternatively, each of the light-emitting portions may include at least one of HIL, HTL, EBL, HBL, ETL, and EIL. In addition, the light-emitting layer may further include CGL disposed between the light-emitting portions.

[0273] At least one of the at least two light-emitting portions may include a first compound H as a host, a second compound DF as a delayed fluorescence material, and optionally a third compound FD as a fluorescent material or a phosphorescent material.

[0274] The bank layer 1060 is disposed on the passivation layer 1050 to cover the edge of the first electrode 1110. The bank layer 1060 corresponds to each of the first to third pixel regions P1, P2, and P3 and exposes the center of the first electrode 1110. As described above, since the OLED D emits white light in the first pixel region P1, the second pixel region P2, and the third pixel region P3, the light-emitting layer 1120 may be formed as a common layer without being separated in the first pixel region P1, the second pixel region P2, and the third pixel region P3. The bank layer 1060 is formed to prevent current leakage from the edge of the first electrode 1110, and the bank layer 1060 may be omitted.

[0275] In addition, the organic light-emitting display device 1000 may further include a packaging film disposed on the second electrode 1130 to prevent external moisture from penetrating into the OLED D. In addition, the organic light-emitting display device 1000 may further include a polarizer disposed under the substrate 1010 to reduce external light reflection.

[0276] In Figure 13 In the organic light-emitting display device 1000, the first electrode 1110 is a transmissive electrode, the second electrode 1130 is a reflective electrode, and the color filter layer 1020 is disposed between the substrate 1010 and the OLED D. That is, the organic light-emitting display device 1000 is a bottom-emitting type. Alternatively, in the organic light-emitting display device 1000, the first electrode 1110 may be a reflective electrode, the second electrode 1130 may be a transmissive electrode (or a semi-transmissive electrode), and the color filter layer 1020 may be disposed above the OLED D.

[0277] In the organic light-emitting display device 1000, the OLED D located in the first to third pixel regions P1, P2, and P3 emits white light, and the white light passes through each of the first to third pixel regions P1, P2, and P3, so that green, red, and blue are respectively displayed in each of the first to third pixel regions P1, P2, and P3.

[0278] The color conversion film may be disposed between the OLED D and the color filter layer 1020. The color conversion film corresponds to the first to third pixel regions P1, P2, and P3 and includes a blue conversion film, a green conversion film, and a red conversion film that can respectively convert white light emitted from the OLED D into blue light, green light, and red light. For example, the color conversion film may include quantum dots. Accordingly, the organic light emitting display device 1000 may further enhance its color purity. Alternatively, the color conversion film may replace the color filter layer 1020.

[0279] Figure 14 is a schematic cross-sectional view of an OLED showing another exemplary aspect according to the present disclosure. As Figure 14 shown, the OLED D6 includes a first electrode 1110 and a second electrode 1130 facing each other and a light emitting layer 1120 disposed between the first electrode 1110 and the second electrode 1130. The first electrode 1110 may be an anode, and the second electrode 1130 may be a cathode. For example, the first electrode 1110 may be a transmissive electrode, and the second electrode 1130 may be a reflective electrode.

[0280] The light emitting layer 1120 includes a first light emitting portion 1220, a second light emitting portion 1320, and a third light emitting portion 1420. The first light emitting portion 1220 includes a first EML (EML1) 1240, the second light emitting portion 1320 includes a second EML (EML2) 1340, and the third light emitting portion 1420 includes a third EML (EML3) 1440. In addition, the light emitting layer 1120 may further include a first charge generation layer (CGL1) 1280 disposed between the first light emitting portion 1220 and the second light emitting portion 1320 and a second charge generation layer (CGL2) 1380 disposed between the second light emitting portion 1320 and the third light emitting portion 1420. Accordingly, the first light emitting portion 1220, CGL1 1280, the second light emitting portion 1320, CGL2 1380, and the third light emitting portion 1420 are sequentially disposed on the first electrode 1110.

[0281] The first light emitting portion 1220 may further include at least one of a first HTL (HTL1) 1260 disposed between the first electrode 1110 and the EML1 1240, a HIL 1250 disposed between the first electrode 1110 and the HTL1 1260, and a first ETL (ETL1) 1270 disposed between the EML1 1240 and the CGL1 1280. Alternatively, the first light emitting portion 1220 may further include a first EBL (EBL1) 1265 disposed between the HTL1 1260 and the EML1 1240 and / or a first HBL (HBL1) 1275 disposed between the EML1 1240 and the ETL1 1270.

[0282] The second light-emitting part 1320 may further include at least one of a second hole transport layer (HTL2) 1360 disposed between the CGL1 1280 and the EML2 1340 and a second electron transport layer (ETL2) 1370 disposed between the EML2 1340 and the CGL2 1380. Alternatively, the second light-emitting part 1320 may further include a second electron blocking layer (EBL2) 1365 disposed between the HTL2 1360 and the EML2 1340 and / or a second hole blocking layer (HBL2) 1375 disposed between the EML2 1340 and the ETL2 1370.

[0283] The third light-emitting part 1420 may further include at least one of a third hole transport layer (HTL3) 1460 disposed between the CGL2 1380 and the EML3 1440, a third electron transport layer (ETL3) 1470 disposed between the EML3 1440 and the second electrode 1130, and an electron injection layer 1480 disposed between the ETL3 1470 and the second electrode 1130. Alternatively, the third light-emitting part 1420 may further include a third electron blocking layer (EBL3) 1465 disposed between the HTL3 1460 and the EML3 1440 and / or a third hole blocking layer (HBL3) 1475 disposed between the EML3 1440 and the ETL3 1470.

[0284] The CGL1 1280 is disposed between the first light-emitting part 1220 and the second light-emitting part 1320. That is, the first light-emitting part 1220 and the second light-emitting part 1320 are connected via the CGL1 1280. The CGL1 1280 may be a PN junction CGL connecting a first N-type CGL (N-CGL1) 1282 and a first P-type CGL (P-CGL1) 1284.

[0285] The N-CGL1 1282 is disposed between the ETL1 1270 and the HTL2 1360, and the P-CGL1 1284 is disposed between the N-CGL1 1282 and the HTL2 1360. The N-CGL1 1282 transports electrons to the EML1 1240 of the first light-emitting part 1220, and the P-CGL1 1284 transports holes to the EML2 1340 of the second light-emitting part 1320.

[0286] The CGL2 1380 is disposed between the second light-emitting part 1320 and the third light-emitting part 1420. That is, the second light-emitting part 1320 and the third light-emitting part 1420 are connected via the CGL2 1380. The CGL2 1380 may be a PN junction CGL connecting a second N-type CGL (N-CGL2) 1382 and a second P-type CGL (P-CGL2) 1384.

[0287] The N-CGL2 1382 is disposed between the ETL2 1370 and the HTL3 1460, and the P-CGL2 1384 is disposed between the N-CGL2 1382 and the HTL3 1460. The N-CGL2 1382 transfers electrons to the EML2 1340 of the second light-emitting unit 1320, and the P-CGL2 1384 transfers holes to the EML3 1440 of the third light-emitting unit 1420.

[0288] In this regard, one of the first EML 1240, the second EML 1340, and the third EML 1440 may be a blue EML, another one of the first EML 1240, the second EML 1340, and the third EML 1440 may be a green EML, and the third one of the first EML 1240, the second EML 1340, and the third EML 1440 may be a red EML.

[0289] As an example, the EML1 1240 may be a blue EML, the EML2 1340 may be a green EML, and the EML3 1440 may be a red EML. Alternatively, the EML1 1240 may be a red EML, the EML2 1340 may be a green EML, and the EML3 1440 may be a blue EML1.

[0290] The EML1 1240 includes a host and a blue dopant (or a red dopant), and the EML3 1440 includes a host and a red dopant (or a blue dopant). As an example, the host in each of the EML1 1240 and the EML3 1440 may include a blue host or a red host, and the blue dopant or the red dopant may include at least one of the blue phosphorescent material or the red phosphorescent material, the blue fluorescent material or the red fluorescent material, and the blue delayed fluorescent material or the red delayed fluorescent material as described above.

[0291] The EML2 1340 may include a first compound H as a host, a second compound DF as a delayed fluorescent material, and optionally a third compound FD as a fluorescent material or a phosphorescent material. The EML2 1340 including the first compound H, the second compound DF, and the third compound FD may have a single-layer structure, a double-layer structure ( Figure 6 ) or a triple-layer structure ( Figure 8 ).

[0292] When the EML2 1340 contains the first compound H, the second compound DF, and the third compound FD, the content of the first compound H can be greater than the content of the second compound DF, and the content of the second compound DF can be greater than the content of the third compound FD. In this case, the exciton energy can be effectively transferred from the second compound DF to the third compound FD. As an example, the contents of the first compound H, the second compound DF, and the third compound FD in the EML2 1340 can be respectively about 60 wt% to about 75 wt%, about 20 wt% to about 40 wt%, and about 0.1 wt% to about 5 wt%, but not limited thereto.

[0293] The OLED D6 emits white light in each of the first to third pixel regions P1, P2, and P3, and the white light passes through the color filter layers 1020 ( Figure 13 ) respectively provided in the first to third pixel regions P1, P2, and P3. Accordingly, the OLED D6 can achieve a full-color image.

[0294] Figure 15 is a schematic cross-sectional view of an OLED showing another exemplary aspect according to the present disclosure. As Figure 15 shown, the OLED D7 includes a first electrode 1110 and a second electrode 1130 facing each other and a light-emitting layer 1120A provided between the first electrode 1110 and the second electrode 1130. The first electrode 1110 can be an anode, and the second electrode 1130 can be a cathode. For example, the first electrode 1110 can be a transmissive electrode, and the second electrode 1130 can be a reflective electrode.

[0295] The light-emitting layer 1120A includes a first light-emitting portion 1520, a second light-emitting portion 1620, and a third light-emitting portion 1720. The first light-emitting portion 1520 includes the EML1 1540, the second light-emitting portion 1620 includes the EML2 1640, and the third light-emitting portion 1720 includes the EML3 1740. In addition, the light-emitting layer 1120A may further include a CGL1 1580 provided between the first light-emitting portion 1520 and the second light-emitting portion 1620 and a CGL2 1680 provided between the second light-emitting portion 1620 and the third light-emitting portion 1720. Accordingly, the first light-emitting portion 1520, the CGL1 1580, the second light-emitting portion 1620, the CGL2 1680, and the third light-emitting portion 1720 are sequentially provided on the first electrode 1110.

[0296] The first light-emitting part 1520 may further include at least one of an HTL1 1560 disposed between the first electrode 1110 and the EML1 1540, a HIL 1550 disposed between the first electrode 1110 and the HTL1 1560, and an ETL1 1570 disposed between the EML1 1540 and the CGL1 1580. Alternatively, the first light-emitting part 1520 may further include an EBL1 1565 disposed between the HTL1 1560 and the EML1 1540 and / or a HBL1 1575 disposed between the EML1 1540 and the ETL1 1570.

[0297] The EML2 1640 of the second light-emitting part 1620 includes a lower EML 1642 and an upper EML 1644. The lower EML 1642 is positioned adjacent to the first electrode 1110, and the upper EML 1644 is also positioned adjacent to the second electrode 1130. In addition, the second light-emitting part 1620 may further include at least one of an HTL2 1660 disposed between the CGL1 1580 and the EML2 1640 and an ETL2 1670 disposed between the EML2 1640 and the CGL2 1680. Alternatively, the second light-emitting part 1620 may further include an EBL2 1665 disposed between the HTL2 1660 and the EML2 1640 and / or a HBL2 1675 disposed between the EML2 1640 and the ETL2 1670.

[0298] The third light-emitting part 1720 may further include at least one of an HTL3 1760 disposed between the CGL2 1680 and the EML3 1740, an ETL3 1770 disposed between the EML3 1740 and the second electrode 1130, and an EIL 1780 disposed between the ETL3 1770 and the second electrode 1130. Alternatively, the third light-emitting part 1720 may further include an EBL3 1765 disposed between the HTL3 1760 and the EML3 1740 and / or a HBL3 1775 disposed between the EML3 1740 and the ETL3 1770.

[0299] The CGL1 1580 is disposed between the first light-emitting part 1520 and the second light-emitting part 1620. That is, the first light-emitting part 1520 and the second light-emitting part 1620 are connected via the CGL1 1580. The CGL1 1580 may be a PN-junction CGL connecting the N-CGL1 1582 and the P-CGL1 1584. The N-CGL1 1582 is disposed between the ETL1 1570 and the HTL2 1660, and the P-CGL1 1584 is disposed between the N-CGL1 1582 and the HTL2 1660.

[0300] CGL2 1680 is disposed between the second light-emitting part 1620 and the third light-emitting part 1720. That is, the second light-emitting part 1620 and the third light-emitting part 1720 are connected via CGL2 1680. CGL2 1680 can be a PN-junction CGL that connects N-CGL2 1682 and P-CGL2 1684. N-CGL2 1682 is disposed between ETL2 1670 and HTL3 1760, and P-CGL2 1684 is disposed between N-CGL2 1682 and HTL3 1760. In one exemplary aspect, at least one of N-CGL1 1582 and N-CGL2 1682 can include any organic compound having the structures of Formulas 1 to 3.

[0301] In this regard, EML1 1540 and EML3 1740 can each be a blue EML. EML1 1540 and EML3 1740 can each include a host and a blue dopant. The host in each of EML1 1540 and EML3 1740 can include a blue host, and the blue dopant can include at least one of the blue phosphorescent material, blue fluorescent material, and blue delayed fluorescent material as described above. The host and blue dopant in EML1 1540 can each be independently the same as or different from the host and blue dopant in EML3 1740. As an example, the blue dopant in EML1 1540 can be different from the blue dopant in EML3 1740 in terms of luminous efficiency and / or emission wavelength.

[0302] One of the lower EML 1642 and the upper EML 1644 in EML2 1640 can be a green EML, and the other of the lower EML 1642 and the upper EML 1644 in EML2 1640 can be a red EML. The green EML and the red EML are sequentially disposed to form EML2 1640.

[0303] In one exemplary aspect, the lower EML 1642, which is a green EML, can include a first compound H as a host, a second compound DF as a delayed fluorescent material having the structures of Formulas 1 to 12, and optionally a third compound FD as a fluorescent or phosphorescent material.

[0304] The upper EML 1644, which is a red EML, can include a host and a red dopant. The host in the upper EML 1644 can include a red host, and the red dopant in EML 1644 can include at least one of the red phosphorescent material, red fluorescent material, and red delayed fluorescent material as described above.

[0305] As an example, when the current EML 1642 contains the first compound H, the second compound DF, and the third compound FD, the content of the first compound H can be greater than the content of the second compound DF, and the content of the second compound DF can be greater than the content of the third compound FD. In this case, the exciton energy can be effectively transferred from the second compound DF to the third compound FD. As an example, the contents of the first compound H, the second compound DF, and the third compound FD in the following EML 1642 can be about 60 wt% to about 75 wt%, about 20 wt% to about 40 wt%, and about 0.1 wt% to about 5 wt%, respectively, but are not limited thereto.

[0306] OLED D7 emits white light in each of the first pixel region P1, the second pixel region P2, and the third pixel region P3, and the white light passes through the color filter layer 1020 ([ Figure 13 ) correspondingly disposed in the first pixel region P1, the second pixel region P2, and the third pixel region P3. Therefore, OLED D7 can achieve a full-color image.

[0307] In Figure 15 , OLED D7 has a three-stack structure including a first light-emitting part 1520, a second light-emitting part 1620, and a third light-emitting part 1720, which includes EML1 1540 and EML3 1740 as blue EMLs. Alternatively, OLED D7 can have a two-stack structure, in which one of the first light-emitting part 1520 and the third light-emitting part 1720, each including EML1 1540 and EML3 1740 as blue EMLs, is omitted.

[0308] Comparative Synthesis Example 1: Synthesis of Compound Ref.1

[0309] (1) Synthesis of Intermediate A

[0310] [Comparative Reaction Scheme 1-1]

[0311]

[0312] Put 2-chloro-4,6-diphenyl-1,3,5-triazine (2.00 g, 7.47 mmol), 3-cyano-4-fluorophenylboronic acid (1.38 g, 8.22 mmol), Na2CO3 (3.96 g, 37.35 mmol), and tetrakis(triphenylphosphine)palladium(0) (Pd(PPh3)4, 0.26 g, 0.22 mmol) into a two-necked flask, and then dissolve the mixture in 200 mL of the mixed solvent 1,4-di in alkane / H2O (volume ratio 4:1). Then, the solution was refluxed for 12 hours with stirring. After the reaction was completed, the crude product was purified by column chromatography using dichloromethane (MC) and hexane (volume ratio 3:7) as the eluent to obtain solid intermediate A (2.10 g, yield: 79.78%).

[0313] (2) Synthesis of Compound Ref.1

[0314] [Comparative Reaction Scheme 1-2]

[0315]

[0316] Intermediate A (5.0 g, 14.19 mmol), 5-phenyl-5,12-dihydroindolo[3,2-a]carbazole (5.2 g, 15.91 mmol), and Cs2CO3 (9.2 g, 28.38 mmol) dissolved in 150 mL of DMA (dimethylacetamide) were placed in a two-necked flask, and then the solution was heated at 150 °C for 3 hours with stirring. After the reaction was completed, the reaction mixture was extracted with MC / H2O, dried over MgSO4, and then filtered. After concentrating the reaction mixture, the crude product was solidified with methanol and then filtered to obtain solid compound Ref.1 (7.2 g, yield: 77%).

[0317] Comparative Synthesis Example 2: Synthesis of Compound Ref.2

[0318] (1) Synthesis of Intermediate B

[0319] [Comparative Reaction Scheme 2-1]

[0320]

[0321] Benzamidine hydrochloride (50 g, 322.56 mmol), ethyl cyanoacetate (36.5 g, 322.56 mmol), benzaldehyde (59 g, 322.56 mmol), Bi(NO3)3·5H2O (7.8 g, 16.13 mmol), and trimethylamine (230 mL, 16.13 mmol) dissolved in 800 mL of acetonitrile were placed in a two-necked flask, and then the solution was heated at 80 °C for 4 hours with stirring. After the reaction was completed, the mixed solution was cooled to room temperature, extracted with H2O / MC, dried over MgSO4, and filtered. The solvent was concentrated under vacuum distillation and recrystallized from ethanol to obtain white solid intermediate B (35 g, yield: 40%).

[0322] (2) Synthesis of Intermediate C

[0323] [Comparative Reaction Scheme 2-2]

[0324]

[0325] Intermediate B (35 g, 128.06 mmol) dissolved in 60 mL of 1,4 - di ane and POCl3 (30 mL, 320.16 mmol) were placed in a two - necked flask, and then the solution was heated at 120 °C overnight with stirring. After the reaction was completed, the reactants were cooled to 0 °C, and then water was added dropwise to the solution to quench the reaction. The reactants were extracted with MC / H2O, dried over MgSO4 and filtered. After concentrating the reactants, the crude product was solidified with methanol and then filtered to obtain solid intermediate C (34.5 g, yield: 92%).

[0326] (3) Synthesis of compound Ref.2

[0327] [Comparative Reaction Scheme 2 - 3]

[0328]

[0329] Intermediate C (3.2 g, 10.83 mmol), 5 - phenyl - 5,7 - dihydroindolo[2,3 - b]carbazole (3.0 g, 9.03 mmol), bis(dibenzylideneacetone)palladium(0) (Pd(dba)2, 260 mg, 0.45 mmol), 2 - dicyclohexylphosphino - 2’,6’ - dimethoxybiphenyl (sPhos, 370 mg, 0.90 mmol) and sodium hydroxide (1.1 g, 27.08 mmol) dissolved in 90 mL of xylene were placed in a two - necked flask, and the reactants were reacted at 150 °C for 2.5 hours with stirring. After the solution was cooled to room temperature, the reactants were extracted with MC / H2O, dried over MgSO4 and then filtered. After concentrating the reactants, the crude product was purified by column chromatography (eluent: ethyl acetate / MC) to obtain solid compound Ref.2 (5.6 g, yield: 79%).

[0330] Comparative Synthesis Example 3: Synthesis of Compound Ref.3

[0331] (1) Synthesis of intermediate D

[0332] [Comparative Reaction Scheme 3 - 1]

[0333]

[0334] Intermediate D (2.01 g, yield: 78%) was obtained by repeating the synthesis process of intermediate A, except that intermediate C was used as the reactant instead of 2 - chloro - 4,6 - diphenyl - 1,3,5 - triazine. (2) Synthesis of compound Ref.3

[0335] [Comparative Reaction Scheme 3 - 2]

[0336]

[0337] Compound Ref.3 (2.28 g, yield: 77%) was obtained by repeating the synthetic process of Compound Ref.1, except that Intermediate D was used as a reactant instead of Intermediate A.

[0338] Synthesis Example 1: Synthesis of Compound 1-27

[0339] (1) Synthesis of intermediate E

[0340] [Reaction formula 1-1]

[0341]

[0342] Sequentially dissolve in 510 mL of mixed solvent 1,4-dihydro 2-Chloro-4,6-diphenyl-1,3,6-triazine (13.8 g, 51.41 mmol), 3-cyano-4-chlorophenylboronic acid (11.2 g, 61.69 mmol), Pd(PPh3)4 (3.0 g, 2.571 mmol) and Na2CO3 (16.3 g, 154.23 mmol) in alkane / H2O (volume ratio of 4:1) were placed in a two-necked flask, and the solution was reacted at 120° C. overnight. When a gray solid was obtained, the reactant was washed with water and methanol and filtered to obtain a solid intermediate E (9.3 g, yield: 49%).

[0343] (2) Synthesis of intermediate F

[0344] [Reaction 1-2]

[0345]

[0346] 5,7-diphenyl-5,7-dihydroindole [2,3-b] carbazole (5.9 g, 14.44 mmol) dissolved in 140 mL of dimethylformamide (DMF) was placed in a two-necked flask, and N-bromosuccinimide (NBS, 2.6 g, 14.44 mmol) was slowly added dropwise to the solution. The reactants were allowed to react at room temperature for 6 hours. After the reaction was completed, the reactants were extracted with MC / H2O, dried with MgSO4 and filtered. After the reactants were concentrated, the crude product was dissolved in MC and then recrystallized with methanol to obtain solid intermediate F (5.0 g, yield: 71%).

[0347] (3) Synthesis of intermediate G

[0348] [Reaction 1-3]

[0349]

[0350] Intermediate F (5.0 g, 10.26 mmol) dissolved in 100 mL of solvent 1,4-diiodo alkane, bis(pinacolato)diboron (3.9 g, 15.39 mmol), potassium acetate (KOAc, 3.0 g, 30.78 mmol), and [1,1'-bis(diphenylphosphino)dichloropalladium(II) (PdCl2(dppf), 375 mg, 0.51 mmol) were placed in a two-necked flask, and then the solution was refluxed with stirring for 3.5 hours. After cooling the reaction mixture to room temperature, the reaction mixture was extracted with MC / H2O, dried over MgSO4, and filtered. After concentrating the reaction mixture, the crude product was dissolved in MC and recrystallized from methanol to obtain solid intermediate G (3.3 g, yield: 60%).

[0351] (4) Synthesis of Compound 1-27

[0352] [Reaction Scheme 1-4]

[0353]

[0354] Intermediate E (2.73 g, 7.40 mmol), intermediate G (3.3 g, 6.17 mmol), Pd(PPh3)4 (0.36 g, 0.31 mmol), and Na2CO3 (2.0 g, 18.52 mmol) dissolved in 62 mL of a mixed solvent of 1,4-diiodo alkane / H2O (volume ratio 4:1) were placed in a two-necked flask, and then the reaction mixture was stirred overnight at 120 °C. After completion of the reaction, the reaction mixture was extracted with MC / H2O, dried over MgSO4, and filtered. After concentrating the reaction mixture, the crude product was dissolved in MC and recrystallized from methanol to obtain solid compound 1-27 (5.2 g, yield: 95%).

[0355] Synthesis Example 2: Synthesis of Compound 1-12

[0356] (1) Synthesis of Intermediate H

[0357] [Reaction Scheme 2-1]

[0358]

[0359] Intermediate H (7.40 g, yield: 62%) was obtained by repeating the synthesis procedure of intermediate F, except that 5,8-diphenyl-5,8-dihydroindolo[2,3-c]carbazole (10.0 g, 24.48 mmol) was used as the reactant instead of 5,7-diphenyl-5,7-dihydroindolo[2,3-b]carbazole.

[0360] (2) Synthesis of Intermediate I

[0361] [Reaction formula 2-2]

[0362]

[0363] Intermediate I (3.40 g, yield: 62%) was obtained by repeating the synthesis process of intermediate G, with the difference that intermediate H (5.0 g, 10.25 mmol) was used as the reactant instead of intermediate F.

[0364] (3) Synthesis of compound 1-12

[0365] [Reaction formula 2-3]

[0366]

[0367] Compound 1-12 (2.11 g, yield: 76%) was obtained by repeating the synthesis process of compound 1-27, with the difference that intermediate I (2.0 g, 3.74 mmol) was used as the reactant instead of intermediate G.

[0368] Synthesis Example 3: Synthesis of Compound 1-22

[0369] (1) Synthesis of intermediate J

[0370] [Reaction formula 3-1]

[0371]

[0372] Intermediate J (7.99 g, yield: 67%) was obtained by repeating the synthesis process of intermediate F, with the difference that 5,11-diphenyl-5,11-dihydroindolo[2,3-b]carbazole (10.0 g, 24.48 mmol) was used as the reactant instead of 5,7-diphenyl-5,7-dihydroindolo[2,3-b]carbazole.

[0373] (2) Synthesis of intermediate K

[0374] [Reaction formula 3-2]

[0375]

[0376] Intermediate K (3.18 g, yield: 58%) was obtained by repeating the synthesis process of intermediate G, with the difference that intermediate J (5.0 g, 10.25 mmol) was used as the reactant instead of intermediate F.

[0377] (3) Synthesis of compound 1-22

[0378] [Reaction formula 3-3]

[0379]

[0380] Compound 1-22 was obtained by repeating the synthesis process of Compound 1-27, except that intermediate K (2.0 g, 3.74 mmol) was used as a reactant instead of intermediate G.

[0381] Synthesis Example 4: Synthesis of Compound 2-57

[0382] [Reaction Scheme 4]

[0383]

[0384] Compound 2-57 (3.14 g, yield: 69%) was obtained by repeating the synthesis process of Compound 1-27, except that intermediate C (2.0 g, 6.86 mmol) was used as a reactant instead of intermediate E.

[0385] Synthesis Example 5: Synthesis of Compound 2-42

[0386] [Reaction Scheme 5]

[0387]

[0388] Compound 2-42 (1.96 g, yield: 79%) was obtained by repeating the synthesis process of Compound 2-57, except that intermediate I (2.0 g, 3.74 mmol) was used as a reactant instead of intermediate G.

[0389] Synthesis Example 6: Synthesis of Compound 2-52

[0390] [Reaction Scheme 6]

[0391]

[0392] Compound 2-52 was obtained by repeating the synthesis process of Compound 2-57, except that intermediate K (2.0 g, 3.74 mmol) was used as a reactant instead of intermediate G.

[0393] Synthesis Example 7: Synthesis of Compound 2-27

[0394] (1) Synthesis of Intermediate L

[0395] [Reaction Scheme 7-1]

[0396]

[0397] Intermediate L (5.12 g, yield: 38%) was obtained by repeating the synthesis process of intermediate E, except that intermediate C was used as a reactant instead of 2-chloro-4,6-diphenyl-1,3,5-triazine.

[0398] (2) Synthesis of Compound 2-27

[0399] [Reaction Scheme 7-2]

[0400]

[0401] Compound 2-27 (2.93 g, yield: 75%) was obtained by repeating the synthesis process of Compound 1-27, except that intermediate L (2.0 g, 5.09 mmol) was used as the reactant instead of intermediate E.

[0402] Synthesis Example 8: Synthesis of Compound 2-12

[0403] [Reaction Scheme 8]

[0404]

[0405] Compound 2-12 (2.65 g, yield: 74%) was obtained by repeating the synthesis process of Compound 2-27, except that intermediate I (2.5 g, 4.68 mmol) was used as the reactant instead of intermediate G.

[0406] Synthesis Example 9: Synthesis of Compound 2-22

[0407] [Reaction Scheme 9]

[0408]

[0409] Compound 2-22 (2.83 g, yield: 79%) was obtained by repeating the synthesis process of Compound 2-27, except that intermediate K (2.5 g, 4.68 mmol) was used as the reactant instead of intermediate G.

[0410] Example 1 (Ex.1): Fabrication of OLED

[0411] Fabricate an OLED in which Compound 1-27 (the second compound), a delayed fluorescence material, is applied to the EML. Wash the glass substrate attached with ITO with UV ozone, load it into the vapor system, and then transfer it to the vacuum deposition chamber to deposit other layers on the substrate. Deposit the organic layer by evaporation through a heated boat at a deposition rate of at 10 -7 Torr.

[0412] Anode (ITO, 50 nm); HIL (HAT-CN, 7 nm); HTL (TAPC, 78 nm); EBL (DCDPA, 15 nm); EML (mCBP (host, 50 wt%), Compound 1-27 (dopant, 50 wt%), 40 nm); HBL (B3PYMPM, 10 nm); ETL (TPBi, 30 nm); EIL (LiF, 1.0 nm); and Cathode (Al, 100 nm).

[0413] Then, a cover layer (CPL) was deposited over the cathode, and the device was encapsulated with glass. After depositing the light-emitting layer and the cathode, the OLED was transferred from the deposition chamber to a drying oven for film formation, and then encapsulated using a UV-curable epoxy resin and a moisture absorbent.

[0414] Examples 2 to 9 (Ex.2 to 9): Fabrication of OLED

[0415] OLEDs were fabricated using the same materials as in Example 1, except that Compound 1-12 (Ex.2), Compound 1-22 (Ex.3), Compound 2-57 (Ex.4), Compound 2-42 (Ex.5), Compound 2-52 (Ex.6), Compound 2-27 (Ex.7), Compound 2-12 (Ex.8), or Compound 2-22 (Ex.9) was used as the second compound in the EML instead of Compound 1-27.

[0416] Comparative Examples 1-3 (Ref.1 to 3): Fabrication of OLED

[0417] OLEDs were fabricated using the same materials as in Example 1, except that Compound Ref.1 (Ref.1), Compound Ref.2 (Ref.2), or Compound Ref.3 (Ref.3) was used as the second compound in the EML instead of Compound 1-27.

[0418] Experimental Example 1: Measurement of Luminescence Characteristics of OLED

[0419] Each of the OLEDs fabricated through Ex.1 to 9 and Ref.1 to 3 with a 9 mm 2 light-emitting area was connected to an external power supply, and then the luminescence characteristics of all the diodes were evaluated at room temperature using a constant current source (KEITHLEY) and a photometer PR650. In particular, the driving voltage (V), external quantum efficiency (EQE, %), maximum electroluminescence wavelength (ELλ 2 , nm), and T max at a current density of 12 mA / cm 2 were measured at a current density of 6 mA / cm 95 (the time period from the initial luminance to 95% luminance, hours). The results are shown in Table 1 below.

[0420] Table 1: Luminescence Characteristics of OLED

[0421] Sample Second Compound V EQE <![CDATA[ELλ max > <![CDATA[T 95 > Ref.1 Ref.1 3.3 17.9 520 52 Ref.2 Ref.2 3.3 7.6 552 46 Ref.3 Ref.3 3.6 18.9 548 182 Ex.1 1-27 3.4 19.2 524 482 Ex.2 1-12 3.3 19.4 544 476 Ex.3 1-22 3.4 19.5 532 490 Ex.4 2-57 3.6 18.9 523 530 Ex.5 2-42 3.6 19.6 542 558 Ex.6 2-52 3.5 19.8 542 558 Ex.7 2-27 3.6 17.9 543 584 Ex.8 2-12 3.6 10.9 570 608 Ex.9 2-22 3.5 10.6 568 686

[0422] As shown in Table 1, compared with the OLEDs fabricated in Ref.1 with a second compound having a triazine moiety with an electron acceptor moiety, the OLEDs in Ex.1 to 3, each having a different second compound with the same electron acceptor moiety, increased their EQE and T 95 by up to 8.9% and 8.4 times, respectively. Compared with the OLEDs fabricated in Ref.2 to 3 with a second compound having a pyrimidine moiety with an electron acceptor moiety, the OLEDs in Ex.4 to 9, each having a different second compound with the same electron acceptor moiety, increased their EQE and T 95 by up to 160.5% and 13.9 times, respectively.

[0423] It will be apparent to those skilled in the art that various modifications and variations can be made in the present disclosure without departing from the scope of the disclosure. Accordingly, the disclosure is intended to cover modifications and variations of the disclosure provided they fall within the scope of the appended claims.

Claims

1. An organic compound selected from the following:

2. An organic light-emitting diode, comprising: A first electrode; A second electrode facing the first electrode; And A light-emitting layer disposed between the first electrode and the second electrode, wherein the light-emitting layer contains an organic compound selected from the following:

3. The organic light-emitting diode according to claim 2, wherein the light-emitting layer includes at least one light-emitting material layer, and wherein the at least one light-emitting material layer contains the organic compound.

4. The organic light-emitting diode according to claim 3, wherein the at least one light-emitting material layer contains a first compound and a second compound, and wherein the second compound includes the organic compound.

5. The organic light-emitting diode according to claim 4, wherein the at least one light-emitting material layer further contains a third compound.

6. The organic light-emitting diode according to claim 4, wherein the at least one light-emitting material layer includes a first light-emitting material layer disposed between the first electrode and the second electrode, and a second light-emitting material layer disposed between the first electrode and the first light-emitting material layer or between the first light-emitting material layer and the second electrode.

7. The organic light-emitting diode according to claim 6, wherein the at least one light-emitting material layer further includes a third light-emitting material layer disposed opposite to the second light-emitting material layer with respect to the first light-emitting material layer.

8. An organic light-emitting device, comprising: A substrate; And The organic light-emitting diode according to claim 2 disposed above the substrate.

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