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

Abstract

The present disclosure relates to an organic compound having the following structure, an organic light emitting diode (OLED) including the same, and an organic light emitting device. The organic compound is a bipolar compound having a p-type portion and an n-type portion, and has a high energy level and a proper energy band gap for an emitting layer of an OLED. When the organic compound is applied to the emitting layer, the OLED can maximize its light emitting properties since holes and electrons are uniformly recombined over the entire area of the EML.

Description

[0001] This application is a divisional application of Chinese patent application filed on October 16, 2020, with application number 202011108387.4 and entitled "Organic compound, organic light-emitting diode and organic light-emitting device comprising the organic compound".

[0002] Cross-reference to related applications

[0003] This application claims priority to Korean Patent Application No. 10-2019-0130224, filed on October 18, 2019, and Korean Patent Application No. 10-2020-0112041, filed on September 3, 2020, which are incorporated herein by reference in their entirety. Technical Field

[0004] This disclosure relates to organic compounds, and more specifically, to organic compounds having enhanced light-emitting properties, organic light-emitting diodes comprising said organic compounds, and organic light-emitting devices. Background Technology

[0005] As display devices become larger, there is a demand for flat panel displays with lower space requirements. Among the currently widely used flat panel displays, displays with organic light-emitting diodes (OLEDs) are rapidly replacing liquid crystal displays (LCDs).

[0006] OLEDs can be formed with a thickness of less than OLEDs are thin films, and with different electrode configurations, unidirectional or bidirectional images can be achieved. Furthermore, OLEDs can be formed on flexible transparent substrates, such as plastic substrates, making it easy to realize flexible or foldable displays. Additionally, OLEDs can be driven at relatively low voltages of 10V or less. Moreover, compared to plasma display panels and inorganic electroluminescent devices, OLEDs have relatively low driving power consumption, and their color purity is extremely high. In particular, OLEDs can realize red, green, and blue light, thus attracting widespread attention as light-emitting devices.

[0007] In OLEDs, holes injected from the anode and electrons injected from the cathode recombine in the EML to form excitons, which are unstable excited states. These excitons then transition to the stable ground state, emitting light. Conventional fluorescent materials, where only singlet excitons participate in the light emission process, exhibit low luminous efficiency. Phosphorescent materials, where triplet and singlet excitons participate, demonstrate relatively high luminous efficiency. However, metal complexes (representative phosphorescent materials) have too short a luminescent lifetime for commercial applications. In particular, luminescent materials used to achieve blue light emission exhibit degraded luminescent properties and lifetimes. Summary of the Invention

[0008] Therefore, this disclosure relates to organic compounds and OLEDs and organic light-emitting devices containing such organic compounds, which substantially eliminate one or more problems caused by the limitations and disadvantages of related technologies.

[0009] Furthermore, this disclosure provides organic compounds having high excitation triplet energy levels and bipolar characteristics, OLEDs using said organic compounds, and organic light-emitting devices.

[0010] Furthermore, this disclosure provides organic compounds with excellent thermal stability and high affinity for charge, OLEDs having said compounds, and organic light-emitting devices.

[0011] Further features and aspects will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practicing the inventive concept provided herein. Other features and aspects of the inventive concept may be realized and obtained by means of structures specifically pointed out in the written description or which may be derived therefrom, the claims, and the drawings.

[0012] In order to achieve these and other aspects of this disclosure, as specifically embodied and broadly described, this disclosure provides organic compounds having the structure of the following chemical formula 1:

[0013] [Chemical Formula 1]

[0014]

[0015] Wherein R1 is an unsubstituted or substituted fused heteroaromatic group having 3 to 6 aromatic rings or heteroaromatic rings and having 1 to 3 nitrogen atoms, or an unsubstituted or substituted C6-C group. 30 Aromatic amino groups, or unsubstituted or substituted C4-C 30 Heteroaromatic amino groups; R2 and R3 are each independently selected from hydrogen, unsubstituted or substituted C1-C. 30 Alkyl, unsubstituted or substituted C6-C 30 Aromatic groups and unsubstituted or substituted C3-C 30 A heteroaromatic group, wherein each of R2 and R3 is the same or different from each other when a and b are each independently an integer of 2 or greater; a and b are each independently the number of substituents, where a is an integer from 0 (zero) to 3 and b is an integer from 0 (zero) to 4; X and Y are each independently CR4R5, wherein R4 and R5 are each independently selected from hydrogen, unsubstituted or substituted C1-C 30 Alkyl, unsubstituted or substituted C6-C 30 Aromatic groups and unsubstituted or substituted C3-C 30 heteroaromatic groups, or R4 and R5 forming C6-C 20 Aroma rings or C3-C20 Heteroaromatic ring; m and n are each 0 (zero) or 1, where m + n = 1; Z is S, O, or NR6, where R6 is hydrogen, unsubstituted or substituted C1-C. 30 Alkyl, unsubstituted or substituted C6-C 30 Aromatic groups, or unsubstituted or substituted C3-C 30 Mixed aromatic groups.

[0016] In another aspect, this disclosure provides an OLED 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 comprises the organic compound.

[0017] For example, at least one of the electron transport layer (ETL), hole blocking layer (HBL), light-emitting material layer (EML), and charge generating layer (CGL) may contain the organic compound.

[0018] As an example, the EML may contain the organic compound as the main body, and in this case, the EML may also contain at least one dopant such as a delayed fluorescence material, a fluorescent material, and a phosphorescent material.

[0019] In another aspect, this disclosure provides an organic light-emitting device, such as an organic light-emitting display device and an organic light-emitting lighting device, comprising a substrate and an OLED disposed above the substrate as described above.

[0020] It should be understood that the foregoing general description and the following detailed description are exemplary and illustrative, and are intended to provide further explanation of the claimed inventive concept. Attached Figure Description

[0021] The accompanying drawings are included to provide a further understanding of the present disclosure, and are incorporated in and constitute a part of the present disclosure. The drawings illustrate various aspects of the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0022] In the attached diagram:

[0023] Figure 1 This is a schematic cross-sectional view showing an organic light-emitting display device according to an exemplary aspect of the present disclosure;

[0024] Figure 2 This is a schematic cross-sectional view of an OLED according to an exemplary aspect of the present disclosure;

[0025] Figure 3 This is a schematic diagram illustrating the luminescence mechanism of delayed fluorescent materials;

[0026] Figure 4This is a schematic diagram illustrating the light emission mechanism through the energy level band gap between luminescent materials according to an exemplary aspect of this disclosure;

[0027] Figure 5 This is a schematic cross-sectional view of an OLED according to another exemplary aspect of this disclosure;

[0028] Figure 6 This is a schematic diagram illustrating the light emission mechanism through the energy level band gap between light-emitting materials according to another exemplary aspect of this disclosure;

[0029] Figure 7 This is a schematic cross-sectional view of an OLED according to another exemplary aspect of this disclosure;

[0030] Figure 8 This is a schematic diagram illustrating the light emission mechanism through the energy level band gap between light-emitting materials according to another exemplary aspect of this disclosure;

[0031] Figure 9 This is a schematic cross-sectional view of an OLED according to another exemplary aspect of this disclosure;

[0032] Figure 10 This is a schematic diagram illustrating the light emission mechanism through the energy level band gap between light-emitting materials according to another exemplary aspect of this disclosure;

[0033] Figure 11 This is a schematic cross-sectional view of an OLED according to yet another exemplary aspect of the present disclosure;

[0034] Figure 12 This is a schematic cross-sectional view illustrating an organic light-emitting display device according to another exemplary aspect of this disclosure;

[0035] Figure 13 This is a schematic cross-sectional view of an OLED according to yet another exemplary aspect of the present disclosure;

[0036] Figure 14 This is a schematic cross-sectional view showing an organic light-emitting display device according to yet another exemplary aspect of the present disclosure;

[0037] Figure 15 This is a schematic cross-sectional view of an OLED according to yet another exemplary aspect of the present disclosure; and

[0038] Figure 16 This is a schematic cross-sectional view of an OLED according to yet another exemplary aspect of the present disclosure. Detailed Implementation

[0039] The aspects and examples of this disclosure will now be referred to and discussed in detail, some of which are shown in the accompanying drawings.

[0040] [Organic compounds]

[0041] Organic compounds used in organic light-emitting diodes (OLEDs) should possess excellent luminescent properties, high charge affinity, and stable characteristics when driving the OLED. In particular, the luminescent material used in the diode is the most important factor determining the luminescent efficiency of the OLED. The luminescent material should have high quantum efficiency, high charge mobility, and sufficient energy levels relative to other materials used in the same or adjacent layers. The organic compound comprises a fused aromatic ring containing a benzimidazole moiety (which has high electron affinity) and a fused heteroaromatic ring or (hetero)aromatic amino group with high hole affinity. The organic compound according to this disclosure can have the structure of the following chemical formula 1:

[0042] [Chemical Formula 1]

[0043]

[0044] In Formula 1, R1 is an unsubstituted or substituted fused heteroaromatic group having 3 to 6 aromatic or heteroaromatic rings and 1 to 3 nitrogen atoms, and is an unsubstituted or substituted C6-C group. 30 Aromatic amino groups, or unsubstituted or substituted C4-C 30 Heteroaromatic amino groups; R2 and R3 are each independently selected from hydrogen, unsubstituted or substituted C1-C. 30 Alkyl, unsubstituted or substituted C6-C 30 Aromatic groups and unsubstituted or substituted C3-C 30 A heteroaromatic group, wherein each of R2 and R3 is the same or different from each other when a and b are each independently an integer of 2 or greater; a and b are each independently the number of substituents, where a is an integer from 0 (zero) to 3 and b is an integer from 0 (zero) to 4; X and Y are each independently CR4R5, wherein R4 and R5 are each independently selected from hydrogen, unsubstituted or substituted C1-C 30 Alkyl, unsubstituted or substituted C6-C 30 Aromatic groups and unsubstituted or substituted C3-C 30 heteroaromatic groups, or R4 and R5 forming C6-C 20 Aroma rings or C3-C 20 Heteroaromatic ring; m and n are each 0 (zero) or 1, where m + n = 1; Z is S, O, or NR6, where R6 is hydrogen, unsubstituted or substituted C1-C. 30 Alkyl, unsubstituted or substituted C6-C 30 Aromatic groups, or unsubstituted or substituted C3-C 30 Mixed aromatic groups.

[0045] As used herein, the term “unsubstituted” means having a hydrogen atom attached, and in this case, hydrogen includes protium, deuterium, and tritium.

[0046] As used herein, the substituents in the term "substituted" include, but are not limited to, unsubstituted or halogenated C1-C substituents. 20 Alkyl, unsubstituted or halogenated C1-C 20 Alkoxy, halogen, cyano, -CF3, hydroxy, carboxyl, carbonyl, amino, C1-C 10 Alkylamino, C6-C 30 arylamino, C3-C 30 heteroarylamino, C6-C 30 Aryl, C3-C 30 heteroaryl, nitro, gemhydrazine, sulfonate, C1-C 20 Alkyl silyl, C6-C 30 Arylsilyl and C3-C 30 Heteroarylsilyl group.

[0047] As used herein, the term "hetero" in, for example, "heteroaromatic ring," "heterocyclic alkyl," "heteroaryl," "heteroarylalkyl," "heteroaryloxy," "heterocyclic alkyl," "heteroaryl," "heteroarylalkyl," "heteroaryloxy," "heteroarylamino," means that at least one carbon atom constituting an aromatic or alicyclic ring, for example, 1 to 5 carbon atoms, is substituted by at least one heteroatom selected from N, O, S, P, and combinations thereof.

[0048] Organic compounds with the structure of Formula 1 contain a central fused aromatic ring with a benzimidazole moiety that has an excellent affinity for electrons, and therefore exhibit n-type properties that induce electron injection and transport. Furthermore, the fused heteroaromatic ring or (hetero)aromatic amino group attached to the central fused aromatic ring has an excellent affinity for holes, and therefore exhibits p-type properties that induce hole injection and transport. Thus, organic compounds with the structure of Formula 1 exhibit bipolar properties.

[0049] In one aspect, the fused heteroaromatic group in R1 is unsubstituted and selected from C1-C2. 20 Alkyl, C6-C 20 Aryl, C3-C 20 The heteroaryl group and its combination thereof are substituted, or form a spirocyclic structure with a fluorene ring or zeanthrene ring. In another aspect, the fused heteroaryl group in R1 is unsubstituted and is selected from C1-C1. 10 Alkyl, phenyl, carbazole, or combinations thereof are substituted, or a spirocyclic structure is formed with a zeolite ring.

[0050] In one exemplary aspect, the fused heteroaromatic group in R1 is selected from the carbazoyl moiety, acridine moiety, dihydroacridyl moiety, phenazinyl moiety, and phenazinyl moiety. Azine moiety. Examples include carbazoyl moiety, acridine moiety, dihydroacridyl moiety, phenazinyl moiety, and phenanthrene moiety. Each of the azinyl moieties may comprise a carbazoyl, acridineyl, dihydroacridyl, phenazinyl, or phenanthrene group that is either unfused or fused with (but not limited to) a benzene ring, furan ring, thiophene ring, indene ring, and / or indole ring. Azine group.

[0051] As an example, replace C6-C to R1 30 Aryl groups can include, but are not limited to, unfused or fused aryl groups, such as phenyl, biphenyl, terphenyl, naphthyl, anthracene, pentanenyl, indene, indo-indene, heptanenyl, biphenylene, indacenyl, finadeninyl, phenanthrene, benzo[a]phenanthrene, dibenzo[a]phenanthrene, azulenyl, pyrene, fluoranthyl, triphenylene, etc. It contains alkyl, tetraphenylene, pheno-tetraphenyl, pleiadenyl, picenyl, pentaphenylene, pheno-pentaphenyl, fluorenyl, indenefluorenyl, and spirofluorenyl.

[0052] In another exemplary aspect, C3-C in R1 is replaced 30 Heteroaryl groups can independently include, but are not limited to, unfused or fused heteroaryl groups, such as pyrroloyl, pyridyl, pyrimidinyl, pyrazinyl, pyridazinyl, triazinyl, tetraazinyl, imidazolyl, pyrazolyl, indoleyl, isoindoleyl, indazoleyl, indazinyl, pyrroloazinyl, carbazoleyl, benzo[carbazoleyl], dibenzo[carbazoleyl], indolecarbazoleyl, indo[carbazoleyl], benzofuran[carbazoleyl], benzothio[carbazoleyl], carbolinel, quinolinyl, isoquinolinyl, phthalazinyl, quinoxalinyl, cinolinyl, quinazolinyl, quinazinyl, purinyl, benzo[quinolinyl], benzo[isoquinolinyl], benzo[quinazolinyl], benzo[quinoxalinyl], acridineyl, phenazin ... Azinyl, phenothiazinyl, phenanthrolinel, perimidinyl, phenanthidyl, pteridyl, naphthidyl, furanyl, pyranyl azino, azole group, diazole group, triazole group, di Ingyl, benzofuranyl, dibenzofuranyl, thiaranyl, xanthonyl, chromenyl, isochromenyl, thiazinyl, thiophenyl, benzothiophenyl, dibenzothiophenyl, difuran-pyrazinyl, benzofuran-dibenzofuranyl, benzothiophene-benzothiophene, benzothiophene-dibenzothiophene, benzothiophene-benzofuranyl, benzothiophene-dibenzofuranyl, spiroacridyl linked to xanthonyl, dihydroacridyl substituted with at least one C1 to C10 alkyl group and N-substituted spirofluorenyl.

[0053] As an example, when R1 is a fused heteroaromatic group, such as an unfused or fused carbazole group, acridine group, dihydroacridinyl group, phenazinyl group, and phenanthrene group. When aziridine is involved, the fused heteroaromatic group can be further substituted by one to three additional fused heteroaromatic groups. In this case, the additional fused heteroaromatic groups substituted to R1 can include, but are not limited to, carbazolyl, acridinel, dihydroacridyl, phenazinyl, and / or phenazinyl. Azine group.

[0054] As an example, the aryl or heteroaryl group that can be substituted to R1 can have one to three aromatic or heteroaryl rings. When the number of aromatic or heteroaryl rings that can be substituted to R1 increases, the conjugated structure throughout the molecule becomes too long, and therefore the organic compound may have an excessively reduced band gap. As examples, the aryl and heteroaryl groups that can be substituted to R1 can include, but are not limited to, phenyl, biphenyl, naphthyl, anthracene, benzo-furanyl, dibenzo-furanyl, benzo-thiophenyl, dibenzo-thiophenyl, carbazole, acridineyl, phenazinyl, and phenanthreneyl. Azine group and / or phenothiazine group.

[0055] In one exemplary aspect, C6-C in each of R2 to R6 30 Aromatic groups can independently include C6-C. 30 Aryl, C7-C 30 Arylalkyl, C6-C 30 aryloxy groups and C6-C 30 Arylamino group. The C3-C of each of R2 to R6 30 Heteroaromatic groups can independently include C3-C 30 heteroaryl, C4-C 30 Heteroarylalkyl, C3-C 30 Heteroaryl groups and C3-C 30 Heteroarylamino. When the C6-C of each of R2 to R6 is... 30 Aromatic groups or C3-C 30 When the heteroaryl group is aryl or heteroaryl, the aryl or heteroaryl in R2 to R6 can be equivalent to, but not limited to, the aryl or heteroaryl that can be substituted to R1 as described above.

[0056] In one exemplary aspect, R4 and R5 are each unsubstituted or selected from C1-C 10 Alkyl, phenyl, or combinations thereof are substituted, or R4 and R5 are combined to form a fluorene ring. Additionally, Z can be S (sulfur).

[0057] As described above, the organic compound having the structure of Formula 1 comprises a benzimidazole moiety with n-type characteristics and a fused heteroaromatic moiety or (hetero)aromatic amino group with p-type characteristics. This organic compound possesses high excited singlet and triplet energy levels and exhibits excellent thermal stability. When the organic compound is introduced into a light-emitting layer such as an EML, holes and electrons can be injected into the EML in a balanced manner, and recombination regions between holes and electrons can be uniformly distributed throughout the entire region of the EML. Therefore, OLEDs can maximize their luminous efficiency and luminous lifetime.

[0058] Furthermore, because organic compounds contain fused aromatic rings with benzimidazole moieties, they possess a wide band gap between the HOMO (highest occupied molecular orbital) and LUMO (lowest unoccupied molecular orbital) levels, as well as high excited singlet and triplet energy levels, making them suitable as hosts in EMLs (electron light-emitting layers). When organic compounds are used as hosts in EMLs, the exciton energy of the host can be efficiently transferred to the dopant, and exciton quenching caused by the interaction between singlet / triplet excitons of the host or dopant and peripheral hole (or electron)-polarons can be minimized. Therefore, OLEDs with excellent luminous efficiency and improved color purity can be achieved by introducing organic compounds into the emissive layer.

[0059] In one exemplary aspect, an organic compound having the structure of Formula 1 may have, but is not limited to, an excited triplet energy level T1 equal to or greater than about 2.80 eV or about 2.90 eV. Furthermore, the organic compound may have, but is not limited to, a HOMO energy level of about -5.0 eV to about -6.3 eV, a LUMO energy level of about -0.5 eV to about -2.0 eV, and a band gap between the HOMO and LUMO energy levels of about 3.0 eV to about 4.7 eV. Moreover, the organic compound having the structure of Formula 1 exhibits excellent charge affinity and a low HOMO energy level, thus it can be applied to ETL, HBL, or N-type CGLs disposed between luminescent portions.

[0060] In one exemplary aspect, in Formula 1, m is 1 and n is 0 (zero). Such organic compounds may include any of the structures having the following Formula 2:

[0061] [Chemical Formula 2]

[0062]

[0063]

[0064]

[0065]

[0066]

[0067]

[0068]

[0069]

[0070]

[0071] In another exemplary aspect, in Formula 2, m is 0 (zero) and n is 1. Such organic compounds may include any of the structures having the following Formula 3:

[0072] [Chemical Formula 3]

[0073]

[0074]

[0075]

[0076]

[0077]

[0078]

[0079]

[0080]

[0081]

[0082] [Organic light-emitting devices and OLEDs]

[0083] By incorporating organic compounds into the light-emitting layer of an OLED, it is possible to achieve OLEDs with lower driving voltage, excellent luminous efficiency, and improved luminous lifetime. The OLEDs disclosed herein 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 1This is a schematic cross-sectional view of an organic light-emitting display device 100 according to one exemplary aspect of this disclosure. All components of the organic light-emitting display device according to all aspects of this disclosure are operatively coupled and configured. Figure 1 As 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.

[0084] The substrate 110 may include, but is not limited to, glass, thin flexible materials, and / or polymeric plastics. For example, the flexible material may be selected from, but is not limited to, polyimide (PI), polyethersulfone (PES), polyethylene naphthalate (PEN), polyethylene terephthalate (PET), polycarbonate (PC), and combinations thereof. The substrate 110 on which thin-film transistors Tr and OLED D are disposed forms an array substrate.

[0085] A buffer layer 122 can be disposed above the substrate 110, and a thin-film transistor Tr is disposed above the buffer layer 122. The buffer layer 122 can be omitted.

[0086] A semiconductor layer 120 is disposed above a buffer layer 122. In one exemplary aspect, the semiconductor layer 120 may include, but is not limited to, an oxide semiconductor material. In this case, a light-shielding pattern may be formed below the semiconductor layer 120, and this light-shielding pattern can prevent light from incident towards the semiconductor layer 120, thereby preventing the semiconductor layer 120 from deteriorating due to light. Alternatively, the semiconductor layer 120 may include, but is not limited to, polysilicon. In this case, the opposite edges of the semiconductor layer 120 may be doped with impurities.

[0087] 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, inorganic insulating materials, such as silicon oxide (SiO2). x ) or silicon nitride (SiN) x ).

[0088] 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 the gate insulating layer 124 is... Figure 1 The gate insulating layer 124 is disposed over the entire area of ​​the substrate 110 and can be patterned in the same way as the gate electrode 130.

[0089] An interlayer insulating layer 132 formed of an insulating material is disposed on the gate electrode 130 and covers the entire surface of the substrate 110. The interlayer insulating layer 132 may include, but is not limited to, silicon oxide (SiO2). x ) or silicon nitride (SiN) xInorganic insulating materials or organic insulating materials such as benzocyclobutene or photo-acrylic.

[0090] The interlayer insulating layer 132 has a first semiconductor layer contact hole 134 and a second semiconductor layer contact hole 136 exposing both sides of the semiconductor layer 120. The first semiconductor layer contact hole 134 and the second semiconductor layer contact hole 136 are disposed on 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 located on... Figure 1 The first semiconductor layer contact hole 134 and the second semiconductor layer contact hole 136 are formed only in the interlayer insulating layer 132 when the gate insulating layer 124 is patterned in the same way as the gate electrode 130.

[0091] Source electrode 144 and drain electrode 146, formed of a conductive material such as metal, are disposed on interlayer insulating layer 132. Source electrode 144 and drain electrode 146 are spaced apart from each other relative to gate electrode 130, and source electrode 144 and drain electrode 146 contact both sides of semiconductor layer 120 through first semiconductor layer contact hole 134 and second semiconductor layer contact hole 136, respectively.

[0092] Semiconductor layer 120, gate electrode 130, source electrode 144 and drain electrode 146 constitute a thin-film transistor Tr that acts as a driving element. Figure 1 The thin-film transistor Tr has a coplanar structure in which the gate electrode 130, source electrode 144, and drain electrode 146 are disposed above the semiconductor layer 120. Alternatively, the thin-film transistor Tr may have an anti-interleaved structure in which the gate electrode is disposed below the semiconductor layer, and the source and drain electrodes are disposed above the semiconductor layer. In this case, the semiconductor layer may comprise amorphous silicon.

[0093] You can also Figure 1 Gate lines and data lines that intersect each other to define the pixel region are formed, along with switching elements connected to the gate lines and data lines. The switching elements are connected to a thin-film transistor Tr, which serves as a driving element. Furthermore, power lines are spaced parallel to the gate lines or data lines, and the thin-film transistor Tr may also include a storage capacitor configured to constantly maintain the voltage of the gate electrode for one frame.

[0094] Additionally, the organic light-emitting display device 100 may include color filters comprising dyes or pigments for transmitting light of specific wavelengths emitted from the OLED D. For example, the color filters may transmit light of specific wavelengths such as red (R), green (G), blue (B), and / or white (W). Each of the red, green, and blue color filters may be formed separately in each pixel region. In this case, the organic light-emitting display device 100 can achieve full color through the color filters.

[0095] For example, when the organic light-emitting display device 100 is bottom-emitting, the color filter can be disposed on the interlayer insulating layer 132 corresponding to the OLED D. Alternatively, when the organic light-emitting display device 100 is top-emitting, the color filter can be disposed above the OLED D, that is, above the second electrode 230.

[0096] A passivation layer 150 is disposed over the source electrode 144 and drain electrode 146 over the entire substrate 110. The passivation layer 150 has a flat top surface and a drain contact hole 152 that exposes 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 can be spaced apart from the second semiconductor layer contact hole 136.

[0097] The OLED D includes a first electrode 210 disposed on a passivation layer 150 and connected to the drain electrode 146 of the thin-film transistor Tr. The OLED D also 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.

[0098] A first electrode 210 is disposed in each pixel region. The first electrode 210 may be an anode and comprises a conductive material having a relatively high work function value. For example, the first electrode 210 may be, but is not limited to, a transparent conductive material, 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.

[0099] In one exemplary aspect, when the organic light-emitting display device 100 is a bottom-emitting type, the first electrode 201 may have a single-layer structure of a transparent conductive material. Alternatively, when the organic light-emitting display device 100 is a top-emitting type, a reflective electrode or reflective layer may be disposed below the first electrode 210. For example, the reflective electrode or reflective layer may comprise, but is not limited to, a silver (Ag) or aluminum-palladium-copper (APC) alloy. In a top-emitting OLED D, the first electrode 210 may have a three-layer structure of ITO / Ag / ITO or ITO / APC / ITO.

[0100] Furthermore, a dam layer 160 is provided on the passivation layer 150 to cover the edge of the first electrode 210. The dam layer 160 exposes the center of the first electrode 210.

[0101] A light-emitting layer 220 is disposed on the first electrode 210. In one 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 multilayer 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 [link to documentation]). Figure 2 , Figure 5 , Figure 7 and Figure 9 In one aspect, the light-emitting layer 220 may have a single light-emitting portion. Alternatively, the light-emitting layer 220 may have multiple light-emitting portions to form a series structure.

[0102] The luminescent layer 220 comprises any of the structures having chemical formulas 1 to 3. As an example, organic compounds having chemical formulas 1 to 3 can be applied to the host in an EML, or to an ETL, HBL, and N-CGL.

[0103] The second electrode 230 is disposed above the substrate 110 on which the light-emitting layer 220 is disposed. The second electrode 230 can be disposed above the entire display area and can contain a conductive material with a relatively low work function value compared to the first electrode 210. The second electrode 230 can be a cathode. For example, the second electrode 230 can contain, but is not limited to, aluminum (Al), magnesium (Mg), calcium (Ca), silver (Ag), alloys thereof, or combinations thereof, such as aluminum-magnesium alloys (Al-Mg). When the organic light-emitting display device 100 is a top-emitting type, the second electrode 230 is thin, thereby having light transmission (semi-transmission) characteristics.

[0104] In addition, an encapsulation film 170 can 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, but is not limited to, a first inorganic insulating film 172, an organic insulating film 174, and a second inorganic insulating film 176.

[0105] Furthermore, the organic light-emitting display device 100 may include 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 100. Alternatively, when the organic light-emitting display device 100 is a top-emitting type, the polarizer may be disposed above the encapsulation film 170. Additionally, 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, thus the organic light-emitting display device 100 may be a flexible display device.

[0106] As described above, the OLEDD contains any of the structures having chemical formulas 1 to 3 in the light-emitting layer 220. Organic compounds have excellent thermal stability and light-emitting properties; therefore, by incorporating organic compounds into the OLEDD, its luminous efficiency can be improved, its driving voltage and power consumption can be reduced, and its luminous lifetime can be increased.

[0107] Now, we will describe OLED in more detail. Figure 2 This is a schematic cross-sectional view of an OLED according to an exemplary aspect of this disclosure. Figure 2 As shown, 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 OLED D1 can be disposed in any pixel region of the red, green, and blue pixel regions.

[0108] In one exemplary aspect, the light-emitting layer 220 includes an EML 240 disposed between the first electrode 210 and the second electrode 230. Furthermore, 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. Additionally, the light-emitting layer 220 may also 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.

[0109] Alternatively, the light-emitting layer 220 may also include a first exciton blocking layer (i.e., EBL 265) disposed between HTL 260 and EML 240 and / or a second exciton blocking layer (i.e., HBL 275) disposed between EML 240 and ETL 270.

[0110] The first electrode 210 can be an anode that provides holes to the EML 240. The first electrode 210 can contain, 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 can contain, but is not limited to, ITO, IZO, ITZO, SnO, ZnO, ICO, AZO, etc.

[0111] The second electrode 230 can be a cathode that provides electrons to the EML 240. The second electrode 230 may contain, but is not limited to, a conductive material with a relatively low work function value, i.e., a highly reflective material, such as Al, Mg, Ca, Ag, their alloys, combinations thereof, etc.

[0112] In this respect, EML 240 may comprise a first compound (compound 1, the host) and a second compound (compound 2) TD. For example, the first compound may be the (first) host, and the second compound TD may be a dopant such as a fluorescent material, a phosphorescent material, or a delayed fluorescence material. In the following description, EML 240 in which the second compound is a delayed fluorescence material will be explained. As an example, organic compounds having chemical formulas 1 to 3 may be used as the host. For example, EML 240 may emit red (R), green (G), or blue (B) light.

[0113] HIL 250 is disposed between the first electrode 210 and the HTL 260, and improves the interfacial properties between the inorganic first electrode 210 and the organic HTL 260. In one exemplary aspect, HIL 250 may comprise, but is not limited to, 4,4',4"-tris(3-methylphenylamino)triphenylamine (MTDATA), 4,4',4"-tris(N,N-diphenyl-amino)triphenylamine (NATA), 4,4',4"-tris(N-(naphthyl-1-yl)-N-phenyl-amino)triphenylamine (1T-NATA), 4,4',4"-tris(N-(naphthyl-2-yl)-N-phenyl-amino)triphenylamine (2T-NATA), copper phthalocyanine (CuPc), tris(4-carbazolyl-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-hexaazabenzophenanthrene hexanitrile (dipyrazine[2,3-f:2'3'-h]quinoxaline-2,3,6,7,10,11-hexanitrile; HAT-CN), 1,3,5-tris[4-(diphenylamino)phenyl]benzene (TDAPB), poly(3,4-ethylenedioxythiophene)polystyrene sulfonate (PEDOT / PSS) and / or N-(biphenyl-4-yl)-9,9-dimethyl-N-(4-(9-phenyl-9H-carbazol-3-yl)phenyl)-9H-fluorene-2-amine. HIL 250 can be omitted based on the structure of OLED D1.

[0114] HTL 260 is positioned between the first electrode 210 and EML 240, adjacent to EML 240. In one exemplary aspect, HTL 260 may comprise, but is not limited to, 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-butyl) [Phenyl)diphenylamine](TFB), di-[4-(N,N-di-p-tolyl-amino)-phenyl]cyclohexane (TAPC), 3,5-bis(9H-carbazole-9-yl)-N,N-diphenylamine (DCDPA), N-(biphenyl-4-yl)-9,9-dimethyl-N-(4-(9-phenyl-9H-carbazole-3-yl)phenyl)-9H-fluorene-2-amine and / or N-(biphenyl-4-yl)-N-(4-(9-phenyl-9H-carbazole-3-yl)phenyl)biphenyl-4-amine.

[0115] ETL 270 and EIL 280 can be sequentially laminated between EML 240 and the second electrode 230. ETL 270 contains a material with high electron mobility to stably supply electrons to EML 240 via rapid electron transport.

[0116] In one exemplary aspect, ETL 270 may include, but is not limited to, diazole-based compounds, triazole-based compounds, phenanthrene-based compounds, benzo[a]azole-based compounds, benzo[a]thiazole-based compounds, benzimidazole-based compounds, triazine-based compounds, etc.

[0117] As an example, ETL 270 may include, but is not limited to, tris-(8-hydroxyquinoline aluminum (Alq3), 2-biphenyl-4-yl-5-(4-tert-butylphenyl)-1,3,4)-diazole (PBD), spiro-PBD, lithium quinoline (Liq), 1,3,5-tris(N-phenylbenzimidazol-2-yl)benzene (TPBi), bis(2-methyl-8-hydroxyquinoline-N1,O8)-(1,1'-biphenyl-4-ol)aluminum (BAlq), 4,7-diphenyl-1,10-phenanthroline (Bphen), 2,9-bis(naphthyl-2-yl)4,7-diphenyl-1,10-phenanthroline (NBphen), 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), 3-(4-biphenyl) 4-(naphthyl-1-yl)-3,5-diphenyl-4H-1,2,4-triazole (TAZ), 1,3,5-tris(p-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]-alternate-2,7-(9,9-dioctylfluorene)] (PFNBr), tris(phenylquinoxaline) (TPQ) and / or diphenyl-4-triphenylsilyl-phenylphosphine oxide (TSPO1).

[0118] In another exemplary aspect, ETL 270 may comprise any of the structures having chemical formulas 1 to 3. Organic compounds have excellent electron affinity. In this case, ETL 270 may comprise only organic compounds having chemical formulas 1 to 3, or may comprise the aforementioned electron transport material mixed with or doped with said organic compound.

[0119] EIL280 is disposed between the second electrode 230 and ETL 270 and can improve the physical properties of the second electrode 230, thereby improving the lifetime of OLED D1. In one exemplary aspect, EIL 280 may 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 quinoline, lithium benzoate, sodium stearate, etc.

[0120] When holes are transported to the second electrode 230 via EML 240 and / or electrons are transported to the first electrode 210 via 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 disclosure may have at least one exciton blocking layer adjacent to EML 240.

[0121] For example, the exemplary aspect of the OLED D1 includes an EBL 265 between the HTL 260 and the EML 240 to control and prevent electron transport. In one exemplary embodiment, EBL 265 may comprise, but is not limited to: TCTA, tris[4-(diethylamino)phenyl]amine, N-(biphenyl-4-yl)-9,9-dimethyl-N-(4-(9-phenyl-9H-carbazole-3-yl)phenyl)-9H-fluorene-2-amine, TAPC, MTDATA, 1,3-bis(carbazole-9-yl)phenyl (mCP), 3,3'-bis(N-carbazole)-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, and / or 2,8-bis(9-phenyl-9H-carbazole-3-yl)dibenzo[b,d]thiophene.

[0122] Furthermore, the OLED D1 may also include an HBL 275 as a second exciton blocking layer between the EML 240 and the ETL 270, preventing holes from transporting from the EML 240 to the ETL 270. In one exemplary aspect, the HBL 275 may comprise, but is not limited to, diazole-based compounds, triazole-based compounds, phenanthroline-based compounds, benzo[a]azole-based compounds, benzo[a]thiazole-based compounds, benzimidazole-based compounds, and triazine-based compounds, each of which can be used in the ETL 270.

[0123] For example, HBL 275 may contain compounds with relatively low HOMO energy levels compared to the luminescent materials in EML 240. HBL275 may contain, but is not limited to, mCBP, BCP, BAlq, Alq3, PBD, spiro-PBD, Liq, bis-4,5-(3,5-di-3-pyridylphenyl)-2-methylpyrimidine (B3PYMPM), DPEPO, 9-(6-(9H-carbazole-9-yl)pyridin-3-yl)-9H-3,9'-bicarbazole, TSPO1, and combinations thereof.

[0124] In another exemplary aspect, HBL 275 may comprise any of the structures having chemical formulas 1 to 3. The organic compound has a deep HOMO energy level for blocking holes. In this case, HBL 275 may comprise only organic compounds having chemical formulas 1 to 3, or may comprise the aforementioned hole-blocking material mixed with or doped with said organic compound.

[0125] As described above, EML 240 in the first aspect comprises a first compound having any of the structures of chemical formulas 1 to 3, and a second compound that may have delayed fluorescence properties.

[0126] In the prior art, the EML240 uses a p-type host with excellent hole affinity. When a p-type host is applied to the EML240, a recombination region between holes and electrons forms at the interface between the EML 240 and the HBL275 because the p-type host prefers holes to electrons. In this case, some charges injected into the EML 240 cannot recombine with opposite charges to quench them and thus do not participate in the luminescence process, resulting in a deterioration in luminescence efficiency.

[0127] Conversely, organic compounds with chemical formulas 1 to 3 are bipolar compounds. When organic compounds are applied to the bulk of EML 240, recombination regions between holes and electrons are uniformly distributed throughout the entire region of EML 240, including the interface between EML 240 and EBL265. In other words, when organic compounds are applied to EML 240, most of the holes and electrons injected into EML 240 recombine without quenching, allowing OLED D1 to maximize its luminous efficiency.

[0128] External quantum efficiency (EQE, η) of luminescent materials applied to EML 外部 The luminescence efficiency is determined by four factors, such as the singlet / triplet ratio, charge balance factor, radiative efficiency, and external coupling efficiency. Because fluorescent materials utilize only singlet excitons during luminescence, the maximum luminescence efficiency of OLEDs using conventional fluorescent materials is only about 5%.

[0129] On the other hand, phosphorescent materials possess a light-emitting mechanism that converts both singlet and triplet excitons into light. Phosphorescent materials convert singlet excitons into triplet excitons through intersystem crossing (ISC). Therefore, using phosphorescent materials that utilize both singlet and triplet excitons can improve the low luminous efficiency of fluorescent materials. However, blue phosphorescent materials suffer from too low color purity and too short a lifetime to be used in commercial display devices. Therefore, it is necessary to improve upon the shortcomings of phosphorescent materials and the low luminous efficiency of blue phosphorescent materials.

[0130] Delayed fluorescence materials have been developed that can solve the problems associated with conventional fluorescent and / or phosphorescent materials. A representative delayed fluorescence material is thermally-activated delayed fluorescence (TADF) material. Figure 3 This is a schematic diagram illustrating the luminescence mechanism of delayed fluorescent materials in EML.

[0131] like Figure 3 As shown, the singlet energy level S1 in the delayed fluorescence material TD TD The exciton and triplet energy level T1 TD The excitons can transition to an intermediate energy level state, namely the ICT state, and then the excitons in the intermediate state can transition to the ground state (S0). TD S1 TD →ICT←T1 TD Since compounds with the ICT state have almost no orbital overlap between the HOMO and LUMO states, there is virtually no interaction between the HOMO and LUMO states. Therefore, changes in the spin state of electrons have no effect on other electrons, and a new charge transfer band (CT band) that does not follow selection rules is formed within the delayed fluorescence material. When driving an OLED containing the delayed fluorescence material TD, 25% of the singlet excitons and 75% of the triplet excitons are converted to the ICT state by heating, and then the converted excitons emit light when they transfer to the ground state S0. Therefore, the delayed fluorescence material TD can theoretically have 100% internal quantum efficiency.

[0132] Delayed fluorescence materials (TDs) must have an excited singlet energy level S1. TD With the excited triplet energy level T1 TD The band gap ΔE between the energy levels is equal to or less than about 0.3 eV, for example, about 0.05 eV to about 0.3 eV. ST TD This causes the singlet state energy level S1 to be excited. TD and the excited triplet energy level T1 TD The exciton energy in both can be transferred to the ICT state. In the singlet level S1... TD With triplet energy level T1 TDMaterials with very small band gaps between energy levels can exhibit singlet energy levels S1. TD The exciton can directly transfer to the ground state S0. TD Ordinary fluorescence; and delayed fluorescence exhibited by intersystem crossing (RISC), in which the triplet energy level T1 TD The exciton can transition upwards to the singlet level S1. TD The exciton, and then from the triplet energy level T1 TD The transferred singlet energy level S1 TD The exciton can transfer to the ground state S0 TD .

[0133] Since delayed-fluorescence (TD) materials theoretically achieve 100% luminescence efficiency, they can realize excellent internal quantum efficiencies similar to those of conventional phosphorescent materials. In this case, the host material can induce triplet excitons at the TD material to participate in the luminescence process without quenching or nonradiative recombination. Therefore, the energy levels between the host material and the TD material should be tuned.

[0134] Figure 4 This is a schematic diagram illustrating the light emission mechanism through the energy level band gap between luminescent materials, according to an exemplary aspect of this disclosure. Figure 4 As shown, the excited singlet state energy level S1 of the first compound H, which can serve as the host in EML 240, is... H and the excited triplet energy level T1 H Each of them is higher than the excited singlet energy level S1 of the second compound TD, which has delayed fluorescence properties. TD and the excited triplet energy level T1 TD Each of them. As an example, the excited triplet energy level T1 of the first compound H. H It can be compared to the excited triplet energy level T1 of the second compound TD. TD The voltage is at least about 0.2 eV, at least about 0.3 eV, or at least about 0.5 eV.

[0135] When the excited triplet energy level T1 of the first compound H H and the excited singlet state energy level S1 H None of them are as powerful as the excited triplet energy level T1 of the second compound TD. TD and the excited singlet state energy level S1 TD When each of the three states is high, the triplet exciton energy of the second compound TD can be reverse-transferred to the excited triplet energy level T1 of the first compound H. HIn this case, the triplet exciton of the first compound H, which reverses to a state that cannot emit triplet excitons, acts as a non-luminescent quencher, preventing the triplet exciton energy of the second compound TD, which exhibits delayed fluorescence, from contributing to luminescence. The excited singlet level S1 of the second compound TD, which exhibits delayed fluorescence... TD With the excited triplet energy level T1 TD The energy level band gap ΔE between ST TD It can be equal to or less than about 0.3 eV, for example, about 0.05 eV to about 0.3 eV (see...). Figure 3 ).

[0136] Furthermore, the HOMO and LUMO energy levels of the first compound H and the second compound TD need to be appropriately tuned. For example, the HOMO energy level (HOMO) of the first compound H... H ) and the HOMO energy level of the second compound TD (HOMO TD The energy level band gap between (|HOMO) H -HOMO TD |), or the LUMO level of the first compound H (LUMO H ) and the LUMO energy level of the second compound TD (LUMO TD The energy level band gap between (|LUMO) H -LUMO TD |) can be equal to or less than about 0.5 eV, for example, about 0.1 eV to about 0.5 eV.

[0137] When EML 240 contains a first compound H (any organic compound having the structure of chemical formulas 1 to 3) and a second compound TD with delayed fluorescence properties, exciton energy can be transferred to the second compound TD without energy loss during luminescence. In this case, exciton quenching caused by the interaction between the host exciton and adjacent polarons can be minimized, and reduction in luminescence lifetime due to electro-oxidation and photo-oxidation can be prevented.

[0138] The second compound can be a delayed fluorescent material that emits blue, green, or red light. In one exemplary aspect, the second compound serving as the blue-emitting delayed fluorescent material in EML 240 can include, but is not limited to, 10-(4-(diphenylphospho)phenyl)-10H-phenazine (SPXZPO), 10,10'-(4,4'-(phenylphospho)bis(4,1-phenylene))bis(10H-phenazine) (DPXZPO), 10,10',10”-(4,4',4”-phosphotris(phenyl-4,1-diyl))tris(10H-phenazine) (TPXZPO), 9,9'-(5-(4,6-diphenyl-1,3,5-triazin-2-yl)-1,3-phenylene)bis(9H-carbazole) (DcZTrz), 9,9',9”,9”'-((6 -Phenylacetyl-1,3,5-5-triazine-2,4-diyl)bis(phenyl-5,3,1-triyl)tetra(9H-carbazole) (DDczTrz), 2,7-bis(9,9-dimethylacridin-10(9H)-yl)-9,9-dimethyl-9H-thioxanthoxy-10,10-dioxide (DMTDAc), 9,9'-(4,4'-sulfonylbis(4,1-phenylene))bis(3,6-dimethoxy-9H-carbazole) (DMOC-DPS), 10,10'-(4,4'-sulfonylbis(4,1-phenylene))bis(9,9-dimethyl-9,10-dihydroacridinium) (DMAC-DPS), 10-(4-(4,6- Diphenyl-1,3,5-triazin-2-yl)phenyl)-9,9-dimethyl-9,10-dihydroacrylidine (DMAC-TRZ), 10-phenyl-10H,10'H-spiro[acryl-9,9'-anthracene]-10'-one (ACRSA), 3,6-dibenzoyl-4,5-di(1-methyl-9-phenyl-9H-carbazolyl)-2-ethynylbenzylnitrile (Cz-VPN), 9,9',9”-(5-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl-1,2,3-triyl)tri(9H-carbazole) (TcZTrz), 2'-(10H-phenazin-10-yl)-[1,1':3',1”-terphenyl] 5'-Nitrile (mPTC), bis(4-(9H-3,9'-bicarbazol-9-yl)phenyl)methyl ketone (CC2BP), 9'-[4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl]-3,3”,6,6”-tetraphenyl-9,3':6',9”-ter-9H-carbazole (BDPCC-TPTA), 9'-[4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl]-9,3':6',9”-ter-9H-carbazole (BCC-TPTA), 9-(4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-3',6'-diphenyl-9H-3,9'-Bicarbazole (DPCC-TPTA), 10-(4,6-diphenyl-1,3,5-triazin-2-yl)-10H-phenazine (Phen-TRZ), 9-(4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-9H-carbazole (Cab-Ph-TRZ), 10-(4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-10H-spiro[acridin-9,9'-fluorene] (spiroAC-TRZ), 4,6-bis(9H-carbazole-9-yl)isophthalonitrile (DczIPN), 3CzFCN, and 2,3,4,6-tetra(9H-carbazole-9-yl)-5-fluorobenzylnitrile (4CzFCN).

[0139] In another aspect, the second compound serving as the green luminescent delayed fluorescent material in EML 240 may include, but is not limited to, 5'-(phenazin-10-yl)-[1,1':3',1”-triphenyl]-2'-nitrile (oPTC), 2-biphenyl-4,6-bis(12-phenylindol[2,3-a]carbazole-11-yl)-1,3,5-triazine (PIC-TRZ), 9,9',9”-(5-(4,6-diphenyl-1,3,5-triazin-2-yl)benzene-1,2,3-triyl)tris(3,6-dimenthyl-9H-carbazole (TmCzTrz), 2,5-bis(4-(10H-phenazin-10-yl)benzene 1,3,4-diazole (2PXZ-OXD), bis(4-(9,9-dimethylacridin-10(9H)-yl)phenyl) ketone (DMAC-BP), 2-(9-phenyl-9H-carbazol-3-yl)-10,10-dioxide-9H-thioxanthoxan-9-one (TXO-PhCz), 2,4,5,6-tetra(9H-carbazol-9-yl)isophthalonitrile (4CzIPN), 3,4,5,6-tetra(9H-carbazol-9-yl)isophthalonitrile (4CzPN), 2,3,4,6-tetra(9H-carbazol-9-yl)-5-fluorobenzyl nitrile (4CzFCN), 6,6- (9H,9'H-[3,3'-bicarbazolyl]-9,9'-diyl)bis(4-(9H-carbazo-9-yl)isophthalonitrile (33TczPN), 4,5-bis(5H-benzofuran[3,2-c]carbazo-5-yl)phthalonitrile (BFCz-2CN), 4,5-bis(5H-benzo[4,5]thieno[3,2-c]carbazo-5-yl)phthalonitrile (BTCz-2CN), 4,4”-bis(9,9-dimethylacridin-10(9H)-yl)-[1,1':2',1”-terphenyl]-4',5'-dicarboxynitrile (Ac-VPN), 4,4”- The following compounds are used: bis(10H-phenazin-10-yl)-[1,1':2',1”-triphenyl]-4',5'-dicarboxynitrile (Px-VPN), 5,5'-(9H,9'H-[3,3'-bicarbazole]-9,9'-diyl)di-isophthalonitrile (35IPNDcz), 2,5'-(9H,9'H-[3,3'-bicarbazole]-9,9'-diyl)di-isophthalonitrile (26IPNDcz), 9,9',9”-(5-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl-1,2,3-triyl)tris(9H-carbazole) (TcZTrz), and 32alCTRZ.

[0140] In yet another exemplary aspect, the second compound serving as the red-emitting delayed fluorescent material in EML240 may include, but is not limited to, 1,3-bis[4-(10H-phenazin-10-yl)benzoyl]benzene (mPx2BBP), 2,3,5,6-tetrakis(3,6-diphenylcarbazole-9-yl)-1,4-dicyanobenzene (4CzTPN-Ph), and 10,10'-(sulfonylbis(4,1-phenylene))bis(5-phenyl-5,10 5,10-Dihydrophenazine (PPZ-DPS), 5,10-bis(4-(benzo[d]thiazolyl-2-yl)phenyl)-5,10-dihydrophenazine (DHPZ-2BTZ), 5,10-bis(4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-5,10-dihydrophenazine (DHPZ-2TRZ), and 7,10-bis(4-(diphenylamino)phenyl)-2,3-dicyanopyrazinphenanthrene (TPA-DCPP).

[0141] When EML 240 contains a first compound H as the host and a second compound TD as the delayed fluorescence material, the content of the second compound TD in EML 240 may be, but is not limited to, about 1% by weight to about 70% by weight, about 10% by weight to about 50% by weight, or about 20% by weight to about 50% by weight.

[0142] EML can contain a variety of dopants with different luminescence properties. Figure 5 This is a schematic cross-sectional view illustrating an OLED according to another exemplary aspect of this disclosure. Figure 5 As shown, OLED D2 includes a first electrode 210, a second electrode 230 facing the first electrode 210, and a light-emitting layer 220A disposed between the first electrode 210 and the second electrode 230. The light-emitting layer 220A, having a single light-emitting portion, includes an EML 240A. Organic light-emitting display device 100 ( Figure 1 It includes red pixel areas, green pixel areas, and blue pixel areas, and the OLED D2 can be set in any pixel area among the red, green, and blue pixel areas.

[0143] The light-emitting layer 220A 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. Furthermore, the light-emitting layer 220A may also 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 also 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. The structures of the first electrode 210, the second electrode 230, and the other layers in the light-emitting layer 220A, except for the EML 240A, are substantially the same as the corresponding electrodes and layers in the OLED D1.

[0144] In the second aspect, EML 240A comprises a first compound (compound 1, the host) H, a second compound (compound 2, the first dopant) TD, and a third compound (compound 3, the second dopant) FD. The first compound H can be the host, the second compound TD can be a delayed fluorescence material, and the third compound FD can be a fluorescent material. The first compound H can include any organic compound having a structure having chemical formulas 1 to 3. When EML 240A also includes a fluorescent material and a delayed fluorescence material as dopants, the OLED D2 can further improve its luminous efficiency and color purity by adjusting the energy levels between these luminescent materials.

[0145] When the EML contains only a second compound with delayed fluorescence properties as a dopant, since the dopant can theoretically exhibit 100% internal quantum efficiency, the EML can achieve high internal quantum efficiency, just like existing phosphorescent materials containing heavy metals.

[0146] However, due to bond formation and conformational distortion between electron acceptors and electron donors within delayed-fluorescence (RDF) materials, additional charge-transfer transitions (CT transitions) occur, leading to a variety of geometries. Consequently, RDF materials exhibit very broad FWHM (full width at half maximum) emission spectra during luminescence, resulting in poor color purity. Furthermore, during luminescence, RDF materials utilize triplet and singlet exciton energies to simultaneously rotate every part of their molecular structure, resulting in twisted internal charge transfer (TICT). Therefore, the luminescence lifetime of OLEDs containing only RDF materials may be reduced due to weakened molecular bonding between RDF materials.

[0147] In the second aspect, when using only delayed-fluorescence materials as dopants, EML 240A also contains a third compound, which can be a fluorescent or phosphorescent material, to prevent a decrease in color purity and luminescence lifetime. For example... Figure 6 As shown, the triplet exciton energy of the second compound TD, which has delayed fluorescence properties, is converted upwards to its own singlet exciton energy via a RISC mechanism. Then, the converted singlet exciton energy of the second compound TD can be transferred to the third compound FD (which can be a fluorescent or phosphorescent material) in the same EML 240A via the Forster Resonance Energy Transfer (FRET) mechanism to achieve superfluorescence.

[0148] When EML 240A contains a first compound H, which can be any organic compound having a structure of chemical formulas 1 to 3, a second compound TD having delayed fluorescence properties, and a third compound FD being a fluorescent or phosphorescent material, it is necessary to properly tune the energy levels between these luminescent materials. Figure 6 This is a schematic diagram illustrating the light emission mechanism through the energy level band gap between luminescent materials according to another exemplary aspect of this disclosure.

[0149] The excited singlet energy level S1 of the second compound TD as a delayed fluorescence material TD With the excited triplet energy level T1 TD The energy level band gap ΔE between ST TD It can be equal to or less than about 0.3 eV to achieve delayed fluorescence (see...). Figure 3 Furthermore, the excited singlet energy level S1 of the first compound H, which is the main component... H and the excited triplet energy level T1 H Each of them is higher than the excited singlet energy level S1 of the second compound TD, which is a delayed fluorescence material. TD and the excited triplet energy level T1 TD Each of them. As an example, the excited triplet energy level T1 of the first compound H. H It can be compared to the excited triplet energy level T1 of the second compound TD. TD The voltage is at least about 0.2 eV.

[0150] Furthermore, the excited triplet energy level T1 of the second compound TD TD The excited triplet energy level T1 of the third compound FD, which is used as a fluorescent or phosphorescent material, is higher than that of the third compound FD. FD In one exemplary aspect, the excited singlet state energy level S1 of the second compound TD TD It can be higher than the excited singlet energy level S1 of the third compound FD. FD .

[0151] Furthermore, the HOMO level (HOMO) of the first compound H, which is the main component, is also present. H ) and the HOMO energy level of the second compound TD as a delayed fluorescence material (HOMO TD The energy level band gap between (|HOMO) H -HOMO TD |), or the LUMO level of the first compound H (LUMO H ) and the LUMO energy level of the second compound TD (LUMO TD The energy level band gap between (|LUMO) H -LUMO TD |) can be equal to or less than approximately 0.5 eV.

[0152] For example, the first compound H, which can be the main component, can include any organic compound having a structure having chemical formulas 1 to 3. The second compound can include organic compounds as described in the first aspect.

[0153] The exciton energy should be efficiently transferred from the second compound TD, which is a delayed fluorescence material, to the third compound FD, which is a fluorescence or phosphorescence material, to achieve superfluorescence. As an example, a fluorescence or phosphorescence material having an absorption spectrum with a large overlap region with the emission spectrum of the second compound TD, which has delayed fluorescence properties, can be used as the third compound FD to efficiently transfer the exciton energy from the second compound to the third compound.

[0154] The third compound FD can emit blue (B), green (G), or red (R) light. In one exemplary aspect, the third compound FD, as a fluorescent material, can emit blue (B) light. For example, the third compound can include, but is not limited to, pyrene-based compounds, anthracene-based compounds, fluoranthene-based compounds, and boron-based compounds. For example, the third compound FD, as a fluorescent material emitting blue light, can include any of the structures having the following chemical formula 4:

[0155] [Chemical Formula 4]

[0156]

[0157] In another exemplary aspect, the third compound FD, which is a green-emitting fluorescent material, may include, but is not limited to, a boron-dipyrrolemethylene (4,4-difluoro-4-boron-3a,4a-diaza-s-indahedron, BODIPY) core. Alternatively, a metal complex, which is a blue, green, or red-emitting phosphorescent material, may be used as the third compound FD.

[0158] In one exemplary aspect, the content of the first compound H may be greater than the content of the second compound TD, and the content of the second compound TD may be greater than the content of the third compound FD. In this case, exciton energy can be efficiently transferred from the second compound TD to the third compound FD via the FRET mechanism. As an example, the contents of the first to third compounds H, TD, and FD in EML 240A may each be, but are not limited to, about 60% to about 75% by weight, about 20% to about 40% by weight, and about 0.1% to about 5% by weight, respectively.

[0159] Alternatively, the OLED according to this disclosure may include a multilayer EML. Figure 7 This is a schematic cross-sectional view illustrating an OLED with a double-layer EML according to another exemplary aspect of this disclosure. Figure 8 This is a schematic diagram illustrating the light emission mechanism through the energy level band gap between luminescent materials, according to another exemplary aspect of this disclosure.

[0160] like Figure 7 As shown, the OLED D3 includes a first electrode 310 and a second electrode 330 facing each other, and a light-emitting layer 320 having a single light-emitting unit disposed between the first electrode 310 and the second electrode 330.

[0161] In one exemplary aspect, the light-emitting layer 320 includes an EML 340. Organic light-emitting display device 100 ( Figure 1 The OLED D3 includes red, green, and blue pixel regions, and can be disposed in any of these pixel regions. The light-emitting layer 320 may include at least one of an HTL 360 disposed between the first electrode 310 and the EML 340, and an ETL 370 disposed between the second electrode 330 and the EML 340. Furthermore, the light-emitting layer 320 may further include at least one of a HIL 350 disposed between the first electrode 310 and the HTL 360, and an EIL 380 disposed between the second electrode 330 and the ETL 370. Alternatively, the light-emitting layer 320 may further include an EBL 365 disposed between the HTL 360 and the EML 340 and / or an HBL 375 disposed between the EML 340 and the ETL 370. The construction of the first electrode 310, the second electrode 330, and the other layers in the light-emitting layer 320, except for the EML 340, is substantially the same as the corresponding electrodes and layers in OLED D1 or OLED D2.

[0162] EML 340 includes a first EML (EML1, lower EML, first layer) 342 and a second EML (EML2, upper EML, second layer) 344. EML1 342 is disposed between EBL 365 and HBL 375, and EML2 344 is disposed between EML1 342 and HBL 375. One of EML1 342 and EML2 344 contains a second compound (compound 2, first dopant) TD as a delayed fluorescence material, and the other of EML1 342 and EML2 344 contains a fifth compound (compound 5, second dopant) FD as a fluorescent or phosphorescent material. Furthermore, EML1 342 and EML2 344 each contain a first compound (compound 1, first host (host 1)) H1 and a fourth compound (compound 4, second host (host 2)) H2. In an exemplary third aspect, EML1 342 contains a first compound H1, which can be the first host, and a second compound TD, which can be a delayed fluorescence material. EML2 344 contains a fourth compound H2, which can be a second host, and a fifth compound FD, which can be a fluorescent or phosphorescent material.

[0163] More specifically, EML1 342 comprises a first compound H1, which is any organic compound having a structure of chemical formulas 1 to 3, and a second compound TD, which is a delayed fluorescence material. The triplet exciton energy of the second compound TD can be converted into its own singlet exciton energy via a RISC mechanism. Although the second compound has high internal quantum efficiency, it has poor color purity due to its broad FWHM (full width at half maximum).

[0164] Conversely, EML2 344 may contain a fourth compound H2, which can serve as the second host, and a fifth compound FD, which serves as a fluorescent or phosphorescent material. While the fifth compound FD, as a fluorescent material, has an advantage in color purity due to its narrow FWHM, it has low internal quantum efficiency because its triplet excitons may not participate in the luminescence process.

[0165] However, in this exemplary aspect, the singlet and triplet exciton energies of the second compound with delayed fluorescence properties in EML1 342 can be transferred via the FRET mechanism (which nonradiatively transfers energy through an electric field generated by dipole-dipole interactions) to a fifth compound, which can be a fluorescent or phosphorescent material, located adjacent to EML1 342. Therefore, final luminescence occurs in the fifth compound within EML2 344.

[0166] In other words, in EML1 342, the triplet exciton energy of the second compound TD is converted upwards to its own singlet exciton energy via a RISC mechanism. Then, the converted singlet exciton energy of the second compound TD is transferred to the singlet exciton energy of the fifth compound FD in EML2 344. The fifth compound FD in EML2 344 can emit light using both the triplet and singlet exciton energies. Since the exciton energy generated at the second compound TD, which has delayed fluorescence properties in EML1 342, is effectively transferred from the second compound TD to the fifth compound FD in EML2 344, which serves as a fluorescent or phosphorescent material, superfluorescence can be achieved. In this case, substantial luminescence occurs in EML2344, which contains the fifth compound FD as a fluorescent or phosphorescent material and has a narrow FWHM. Therefore, OLED D3 can improve its quantum efficiency and its color purity due to the narrow FWHM.

[0167] EML1 342 and EML2 344 each contain a first compound H1 as the first host and a fourth compound H2 as the second host. The exciton energies generated at the first compound H1 and the fourth compound H2 should be transferred to the second compound TD, which serves as a delayed fluorescence material, to emit light. Figure 8 As shown, the excited singlet energy levels S1 of the first compound H1 and the fourth compound H2 H1 and S1 H2 and the excited triplet level T1 H1 and T1 H2 Each of them should be higher than the excited singlet state energy level S1 of the second compound TD, which is a delayed fluorescence material. TD and the excited triplet energy level T1 TD Each of them. As an example, the excited triplet energy level T1 of the first compound H1 and the fourth compound H2. H1 and T1 H2 Each of them can be compared to the excited triplet energy level T1 of the second compound TD. TD The voltage is at least about 0.2 eV, for example at least about 0.3 eV, or at least about 0.5 eV.

[0168] The excited singlet state energy level S1 of the fourth compound H2 H2 The excited singlet energy level S1 of the fifth compound FD is higher than that of the compound. FD In this case, the singlet exciton energy generated at the fourth compound H2 can be transferred to the excited singlet level S1 of the fifth compound FD. FD Optionally, the excited triplet energy level T1 of the fourth compound H2 H2 It can be higher than the excited triplet energy level T1 of the fifth compound FD. FD .

[0169] Furthermore, EML 340 must achieve high luminous efficiency and color purity, as well as efficiently transfer exciton energy from the second compound TD in EML1 342 (which is converted to the ICT recombination state via a RISC mechanism) to the fifth compound FD in EML2 344, which serves as a fluorescent or phosphorescent material. To achieve such an OLED D3, the excited triplet energy level T1 of the second compound TD... TD The excited triplet energy level T1 above that of the fifth compound FD FD Optionally, the excited singlet energy level S1 of the second compound TD TD It can be higher than the excited singlet energy level S1 of the fifth compound FD. FD .

[0170] Furthermore, the HOMO energy levels (HOMO) of the first compound H1 and / or the fourth compound H2 H ) and the HOMO energy level of the second compound TD (HOMO TD The energy level band gap between (|HOMO) H -HOMO TD |), or the LUMO energy levels of the first compound H1 and / or the fourth compound H2 (LUMO H ) and the LUMO energy level of the second compound TD (LUMO TD The energy level band gap between (|LUMO) H -LUMO TD |) can be equal to or less than about 0.5 eV. When the luminescent material does not meet the required energy level as described above, the exciton energy is quenched at the second compound TD and the fifth compound FD, or the exciton energy cannot be efficiently transferred from the first compound H1 and the fourth compound H2 to the second compound TD and the fifth compound FD, which may result in a reduced quantum efficiency for OLED D3.

[0171] The first compound H1 and the fourth compound H2 may be the same as or different from each other. For example, the first compound H1 and the fourth compound H2 may each independently comprise any organic compound having a structure having chemical formulas 1 to 3. The second compound TD may be the same as described above.

[0172] The fifth compound FD can have a narrow fluorescence wavelength (FWHM) and an absorption spectrum with a large overlap region with the emission spectrum of the second compound TD. The fifth compound FD can be a fluorescent or phosphorescent material emitting blue, green, or red light. For example, the fifth compound FD can be a fluorescent or phosphorescent material emitting blue, green, or red light as described above.

[0173] In one exemplary embodiment, the contents of the first compound H1 and the fourth compound H2 in EML1 342 and EML2 344 may be greater than or equal to the contents of the second compound TD and the fifth compound FD in the same layer. Furthermore, the content of the second compound TD in EML1 342 may be greater than the content of the fifth compound FD in EML2 344. In this case, exciton energy can be efficiently transferred from the second compound TD to the fifth compound FD via the FRET mechanism. As an example, the content of the second compound TD in EML1 342 may be, but is not limited to, about 1 wt% to about 70 wt%, about 10 wt% to about 50 wt%, or about 20 wt% to about 50 wt%. Furthermore, the content of the fourth compound H2 in EML2 344 may be about 90 wt% to about 99 wt%, or 95 wt% to about 99 wt%, and the content of the fifth compound FD in EML2 344 may be about 1 wt% to about 10 wt%, or about 1 wt% to about 5 wt%.

[0174] In one exemplary aspect, when EML2 344 is disposed adjacent to HBL 375, the fourth compound H2 contained in EML2 344 together with the fifth compound FD can be the same material as HBL 375. In this case, EML2 344 can have both hole-blocking and light-emitting functions. In other words, EML2 344 can act as a buffer layer for blocking holes. In one aspect, if EML2 344 can be both a hole-blocking layer and a light-emitting material layer, HBL375 can be omitted.

[0175] In another exemplary aspect, when EML2 344 is disposed adjacent to EBL 365, the fourth compound H2 can be the same material as EBL 365. In this case, EML2 344 can have both electron blocking and luminescent functions. In other words, EML2 344 can act as a buffer layer for blocking electrons. In one aspect, if EML2 344 can be both an electron blocking layer and a luminescent material layer, EBL 365 can be omitted.

[0176] This will explain an OLED with a three-layer EML. Figure 9 This is a schematic cross-sectional view illustrating an OLED with a three-layer EML according to another exemplary aspect of this disclosure. Figure 10 This is a schematic diagram illustrating the light emission mechanism through the energy level band gap between luminescent materials, according to another exemplary aspect of this disclosure.

[0177] like Figure 9As shown, the OLED D4 includes a first electrode 410 and a second electrode 430 facing each other, and a light-emitting layer 420 having a single light-emitting portion disposed between the first electrode 410 and the second electrode 430. Organic light-emitting display device 100 ( Figure 1 It includes red pixel areas, green pixel areas, and blue pixel areas. The OLED D4 can be set in any pixel area among the red, green, and blue pixel areas.

[0178] In one exemplary aspect, the light-emitting layer 420 includes three EMLs 440. The light-emitting layer 420 may include at least one of an HTL 460 disposed between the first electrode 410 and the EML 440 and an ETL 370 disposed between the second electrode 430 and the EML 440. Furthermore, the light-emitting layer 420 may also include at least one of a HIL 450 disposed between the first electrode 410 and the HTL 460 and an EIL 480 disposed between the second electrode 430 and the ETL 470. Alternatively, the light-emitting layer 420 may also include an EBL 465 disposed between the HTL 460 and the EML 440 and / or an HBL 475 disposed between the EML 440 and the ETL 470. The construction of the first electrode 410, the second electrode 430, and the other layers in the light-emitting layer 420, except for the EML 440, is substantially the same as that of the corresponding electrodes and layers in OLED D1, OLED D2, and OLED D3.

[0179] EML 440 includes a first EML (EML1, middle EML, first layer) 442, a second EML (EML2, lower EML, second layer) 444, and a third EML (EML3, upper EML, third layer) 446. EML1 442 is located between EBL 465 and HBL 475, EML2 444 is located between EBL 465 and EML1 442, and EML3 446 is located between EML1 442 and HBL 475.

[0180] EML1 442 contains a second compound (compound 2, the first dopant) TD, which can be a delayed fluorescence material. EML2444 and EML3 446 each contain a fifth compound (compound 5, the second dopant) FD1 and a seventh compound (compound 7, the third dopant) FD2, respectively, where the fifth and seventh compounds can each be fluorescent or phosphorescent materials. Furthermore, EML1442, EML2444, and EML3 446 each also contain a first compound (compound 1, host 1) H1, a fourth compound (compound 4, host 2) H2, and a sixth compound (compound 6, host 3) H3, each of which can be a first to a third host.

[0181] According to this aspect, the singlet and triplet energies of the second compound TD (i.e., the delayed fluorescent material) in EML1 442 can be transferred via the FRET mechanism to the fifth compound FD1 and the seventh compound FD2, i.e., the fluorescent or phosphorescent materials, respectively contained in EML2 444 and EML3446, which are arranged adjacent to EML1 442. Therefore, final luminescence occurs in the fifth compound FD1 and the seventh compound FD2 in EML2 444 and EML3446.

[0182] The triplet exciton energy of the second compound TD, which exhibits delayed fluorescence in EML1 442, is converted upwards to its own singlet exciton energy via a RISC mechanism. Then, the singlet exciton energy of the second compound TD is transferred to the singlet exciton energies of the fifth compound FD1 and the seventh compound FD2 in EML2 2444 and EML3 446, respectively, because the excited singlet level S1 of the second compound TD... TD The excited singlet energy level S1 is higher than that of compound FD1 (fifth compound) and FD2 (seventh compound). FD1 and S1 FD2 Each of them (see Figure 10 The singlet exciton energy of the second compound TD in EML1 442 is transferred via the FRET mechanism to the fifth compound FD1 and the seventh compound FD2 in EML2 444 and EML3 446, which are located adjacent to EML1 442.

[0183] Compounds FD1 (fifth) and FD2 (seventh) in EML2 444 and EML3 446 can emit light using the singlet and triplet exciton energies derived from compound TD (second) . Compared to compound TD, compounds FD1 and FD2 can each have a narrower fluorescence wavelength (FWHM). Superfluorescence can be achieved because the exciton energy generated at compound TD (second) , which exhibits delayed fluorescence properties in EML1 442, is transferred to compounds FD1 and FD2 in EML2 444 and EML3 446. Specifically, compounds FD1 and FD2 can each have emission spectra with a large overlap region with the absorption spectrum of compound TD, allowing the exciton energy of compound TD to be effectively transferred to each of compounds FD1 and FD2. In this case, substantial luminescence occurs in EML2 444 and EML3 446.

[0184] To achieve effective light emission in EML 440, it is necessary to appropriately adjust the energy levels between the luminescent materials in EML1 442, EML2 444, and EML3446. For example... Figure 10As shown, the excited singlet energy levels S1 of the first compound H1, the fourth compound H2, and the sixth compound H3 (each of which can be the first to the third host) are shown. H1 S1 H2 and S1 H3 and the excited triplet level T1 H1 T1 H2 and T1 H3 Each of them should be higher than the excited singlet energy level S1 of the second compound TD (which can be a delayed fluorescence material). TD and the excited triplet energy level T1 TD Each of them.

[0185] Furthermore, EML 440 must achieve high luminous efficiency and color purity, as well as efficiently transfer exciton energy from the second compound TD in EML1 442 (which is converted to the ICT recombination state via a RISC mechanism) to the fifth compound FD1 and the seventh compound FD2 in EML2 444 and EML3 446, respectively, which are fluorescent or phosphorescent materials. To achieve such an OLED D4, the excited triplet energy level T1 of the second compound TD in EML1 442... TD The excited triplet energy level T1 is higher than that of compound FD1 (fifth compound) and FD2 (seventh compound). FD1 and T1 FD2 Each of them. Or, the excited singlet state energy level S1 of the second compound TD. TD It can be higher than the excited singlet energy level S1 of compounds FD1 (the fifth compound) and FD2 (the seventh compound), which are used as fluorescent or phosphorescent materials. FD1 and S1 FD2 Each of them.

[0186] Furthermore, for efficient luminescence, the exciton energies transferred from compound TD to each of compounds FD1 and FD2 should not be transferred to compounds H2 and H3. As an example, the excited singlet energy levels S1 of compounds H2 and H3... H2 and S1 H3 Each of them can be higher than the excited singlet state energy level S1 of the fifth compound FD1 and the seventh compound FD2, respectively. FD1 and S1 FD2 Each of them.

[0187] EML1 442, EML2 444, and EML3 446 may each comprise a first compound H1, a fourth compound H2, and a sixth compound H3 (each of which may be a first to a third host). For example, each of the first compound H1, the fourth compound H2, and the sixth compound H3 may be the same as or different from each other. For example, the first compound H1, the fourth compound H2, and the sixth compound H3 may each independently comprise any organic compound having a structure having chemical formulas 1 to 3. The second compound TD may be the same as described above.

[0188] Compound FD1 (fifth compound) and compound FD2 (seventh compound) may each have a narrow light-to-weight ratio (FWHM) and an absorption spectrum with a large overlap region with the emission spectrum of compound TD (second compound). Compound FD1 and compound FD2 may each be fluorescent or phosphorescent materials emitting blue, green, or red light. For example, compound FD1 and compound FD2 may each be fluorescent or phosphorescent materials emitting blue, green, or red light as described above.

[0189] In one exemplary aspect, the content of each of the fourth compound H2 and the sixth compound H3 in EML2 444 and EML3 446 may be greater than or equal to the content of each of the fifth and seventh compounds in the same layer. Furthermore, the content of the second compound TD in EML1 442 may be greater than the content of each of the fifth compound FD1 and the seventh compound FD2 in EML2 444 and EML3 446. In this case, exciton energy can be efficiently transferred from the second compound to the fifth and seventh compounds via the FRET mechanism. As an example, the content of the second compound TD in EML1 442 may be, but is not limited to, about 1% by weight to about 70% by weight, or about 10% by weight to about 50% by weight, or about 20% by weight to about 50% by weight. Furthermore, the contents of the fourth compound H2 and the sixth compound H3 in EML2444 and EML3 446 may each be from about 90% to about 99% by weight, or from 95% to about 99% by weight, and the contents of the fifth compound FD1 and the seventh compound FD2 in EML2 444 and EML3 446 may each be from about 1% to about 10% by weight, or from about 1% to about 5% by weight.

[0190] In one exemplary aspect, when EML2 444 is disposed adjacent to EBL 465, the fourth compound H2 contained in EML2 444 together with the fifth compound FD1 can be the same material as EBL 465. In this case, EML2 444 can have both electron blocking and luminescent functions. In other words, EML2 444 can act as a buffer layer for blocking electrons. In one aspect, if EML2 444 can be both an electron blocking layer and a luminescent material layer, EBL465 can be omitted.

[0191] In another exemplary aspect, when EML3 446 is disposed adjacent to HBL 475, the sixth compound H3, contained in EML3 446 together with the seventh compound FD2, can be the same material as HBL 475. In this case, EML3 446 can have both hole-blocking and light-emitting functions. In other words, EML3 446 can act as a buffer layer for blocking holes. In one aspect, if EML3 446 can be both a hole-blocking layer and a light-emitting material layer, HBL475 can be omitted.

[0192] In yet another exemplary aspect, the fourth compound H2 in EML2 444 can be the same material as EBL 465, and the sixth compound H3 in EML3 446 can be the same material as HBL 475. In this aspect, EML2 444 can have both electron blocking and light-emitting functions, and EML3 446 can have both hole blocking and light-emitting functions. In other words, EML2 444 and EML3 446 can each act as a buffer layer for blocking electrons or holes, respectively. In one aspect, if EML2 444 can be both an electron blocking layer and a light-emitting material layer, and EML3 446 can be both a hole blocking layer and a light-emitting material layer, then EBL 465 and HBL 475 can be omitted.

[0193] In another aspect, OLEDs can include multiple light-emitting components. Figure 11 This is a schematic cross-sectional view of an OLED according to another exemplary aspect of this disclosure.

[0194] like Figure 11 As shown, the OLED D5 includes a first electrode 510 and a second electrode 530 facing each other, and a light-emitting layer 520 having two light-emitting portions disposed between the first electrode 510 and the second electrode 530. Organic light-emitting display device 100 ( Figure 1The OLED D5 includes a red pixel region, a green pixel region, and a blue pixel region, and can be disposed in any of the red, green, and blue pixel regions. In one exemplary aspect, the OLED D5 can be disposed in the blue pixel region. The first electrode 510 can be an anode, and the second electrode 530 can be a cathode.

[0195] The light-emitting layer 520 includes a first light-emitting portion 620 and a second light-emitting portion 720. The first light-emitting portion 620 includes a first EML (EML1) 640, and the second light-emitting portion 720 includes a second EML (EML2) 740. In addition, the light-emitting layer 520 may also include a charge generation layer (CGL) 680 disposed between the first light-emitting portion 620 and the second light-emitting portion 720.

[0196] CGL 680 is disposed between the first light-emitting portion 620 and the second light-emitting portion 720, such that the first light-emitting portion 620, CGL 680 and the second light-emitting portion 720 are sequentially disposed on the first electrode 510. In other words, the first light-emitting portion 620 is disposed between the first electrode 510 and CGL 680, and the second light-emitting portion 720 is disposed between the second electrode 530 and CGL 680.

[0197] The first light-emitting portion 620 includes an EML1 640. The first light-emitting portion 620 may further include at least one of a first HTL (HTL1) 660 disposed between the first electrode 510 and the EML1 640, a HIL 650 disposed between the first electrode 510 and the HTL1 660, and a first ETL (ETL1) 670 disposed between the EML1 640 and the CGL 680. Alternatively, the first light-emitting portion 620 may further include a first EBL (EBL1) 665 disposed between the HTL1 660 and the EML1 640 and / or a first HBL (HBL1) 675 disposed between the EML1 640 and the ETL1 670.

[0198] The second light-emitting portion 720 includes EML2 740. The second light-emitting portion 720 may further include at least one of the following: a second HTL (HTL2) 760 disposed between CGL 680 and EML2 740; a second ETL (ETL2) 770 disposed between EML2 740 and the second electrode 530; and an EIL 780 disposed between EML2 770 and the second electrode 530. Alternatively, the second light-emitting portion 720 may further include a second EBL (EBL2) 765 disposed between HTL2 760 and EML2 740 and / or a second HBL (HBL2) 775 disposed between EML2 740 and ETL2 770.

[0199] The first light-emitting portion 620 and the second light-emitting portion 720 are connected by a CGL 680. The CGL 680 can be a PN junction CGL that connects an N-type CGL (N-CGL) 682 and a P-type CGL (P-CGL) 684.

[0200] N-CGL 682 is disposed between ETL1 670 and HTL2 760, while P-CGL 684 is disposed between N-CGL 682 and HTL2 760. N-CGL 682 transfers electrons to EML1 640 of the first light-emitting portion 620, while P-CGL 684 transfers holes to EML2 740 of the second light-emitting portion 720. In one exemplary aspect, N-CGL 682 may comprise any organic compound having a structure having chemical formulas 1 to 3.

[0201] In this respect, each of EML1 640 and EML2 740 may be a blue, green, or red luminescent material layer. For example, at least one of EML1 640 and EML2 740 comprises a first compound H as the main component, a second compound TD as a delayed fluorescence material, and / or a third compound FD as a fluorescent or phosphorescent material. For example, EML1 640 may comprise the first compound, the second compound, and the third compound.

[0202] When EML1 640 contains a first compound H, a second compound TD, and a third compound FD, the content of the first compound H can be greater than the content of the second compound TD, and the content of the second compound TD can be greater than the content of the third compound FD. In this case, exciton energy can be efficiently transferred from the second compound TD to the third compound FD. As an example, the contents of the first compound H, the second compound TD, and the third compound FD in EML1 640 can each be, but are not limited to, about 60% to about 75% by weight, about 20% to about 40% by weight, and about 0.1% to about 5% by weight, respectively.

[0203] In one exemplary aspect, EML2 740 may comprise a first compound H having chemical formulas 1 to 3 as the main component, a second compound TD as a delayed fluorescence material, and / or a third compound FD as a fluorescent or phosphorescent material. Alternatively, EML2 740 may comprise additional compounds different from at least one of the second compound TD and the third compound FD in EML1 640, thus EML2 740 may emit light different from that emitted from EML1 640, or may have a luminous efficiency different from that of EML1 640.

[0204] exist Figure 11In this context, EML1 640 and EML2 740 each have a monolayer structure. Alternatively, EML1 640 and EML2 740, each comprising a first to a third compound, may each have a bilayer structure. Figure 7 or three-layer structure Figure 9 ).

[0205] In OLED D5, the singlet exciton energy of the second compound TD of the delayed fluorescent material is transferred to the third compound FD of the fluorescent or phosphorescent material, where final luminescence occurs. Therefore, OLED D5 can exhibit excellent luminous efficiency and color purity. Furthermore, OLED D5 has a double-stacked structure with blue, green, or red luminescent material layers, which improves its color perception or optimizes its luminous efficiency.

[0206] Figure 12 This is a schematic cross-sectional view illustrating an organic light-emitting display device according to another exemplary aspect of this disclosure. Figure 12 As shown, the organic light-emitting display device 800 includes: a substrate 810 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 810; and an OLED D disposed above and connected to the thin-film transistor Tr. As an example, the first pixel region P1 may be a blue pixel region, the second pixel region P2 may be a green pixel region, and the third pixel region P3 may be a red pixel region.

[0207] The substrate 810 can be a glass substrate or a flexible substrate. For example, the flexible substrate can be any of a PI substrate, a PES substrate, a PEN substrate, a PET substrate, and a PC substrate.

[0208] A buffer layer 812 is disposed above the substrate 810, and the thin-film transistor Tr is disposed above the buffer layer 812. The buffer layer 812 can be omitted. Figure 1 As shown, the thin-film transistor Tr includes a semiconductor layer, a gate electrode, a source electrode, and a drain electrode, and acts as a driving element.

[0209] A passivation layer 850 is disposed above the thin-film transistor Tr. The passivation layer 850 has a flat top surface and a drain contact hole 852 that exposes the drain electrode of the thin-film transistor Tr.

[0210] OLED D is disposed above passivation layer 850 and includes a first electrode 910 connected to the drain electrode of thin-film transistor Tr, and a light-emitting layer 920 and a second electrode 930 sequentially disposed on the first electrode 910. OLED D is disposed in each of the first pixel region P1, the second pixel region P2, and the third pixel region P3, and emits different light in each pixel region. For example, OLED D in the first pixel region P1 can emit blue light, OLED D in the second pixel region P2 can emit green light, and OLED D in the third pixel region P3 can emit red light.

[0211] A first electrode 910 is formed for each of the first pixel region P1, the second pixel region P2, and the third pixel region P3, and a second electrode 930 is formed integrally corresponding to the first pixel region P1, the second pixel region P2, and the third pixel region P3.

[0212] The first electrode 910 can be either an anode or a cathode, and the second electrode 930 can be the other one. Furthermore, one of the first electrode 910 and the second electrode 930 is a transmission (or semi-transmission) electrode, while the other is a reflection electrode.

[0213] For example, the first electrode 910 can be an anode and may contain a conductive material with a relatively high work function value, i.e., a transparent conductive oxide layer of transparent conductive oxide (TCO). The second electrode 930 can be a cathode and may contain a conductive material with a relatively low work function value, i.e., a metallic material layer of low-resistance metal. For example, the first electrode 910 may contain any one of ITO, IZO, ITZO, SnO, ZnO, ICO, and AZO, and the second electrode 930 may contain Al, Mg, Ca, Ag, their alloys, or combinations thereof.

[0214] When the organic light-emitting display device 800 is a bottom-emitting type, the first electrode 910 can have a single-layer structure with a transparent conductive oxide layer.

[0215] Alternatively, when the organic light-emitting display device 800 is a top-emitting type, a reflective electrode or reflective layer can be disposed below the first electrode 910. For example, the reflective electrode or reflective layer may contain, but is not limited to, Ag or APC alloys. In a top-emitting OLED D, the first electrode 910 may have a three-layer structure of ITO / Ag / ITO or ITO / APC / ITO. Furthermore, the second electrode 930 is thin to have light transmission (or semi-transmission) characteristics.

[0216] A light-emitting layer 920 is disposed on the first electrode 910. In one exemplary aspect, the light-emitting layer 920 may have a single-layer structure of an EML. Alternatively, the light-emitting layer 920 may include at least one of HIL, HTL, and EBL sequentially disposed between the first electrode 910 and the EML, and / or at least one of HBL, ETL, and EIL sequentially disposed between the EML and the second electrode 930.

[0217] In one exemplary aspect, the EML of the emissive layer 920 in the first pixel region P1 of the blue pixel region may include a first compound H as the main component, a second compound as a blue delayed fluorescence material, and / or a third compound as a blue fluorescent or phosphorescent material. The EML of the emissive layer 920 in the second pixel region P2 of the green pixel region may include a first compound H as the main component, a second compound as a green delayed fluorescence material, and / or a third compound as a green fluorescent or phosphorescent material. The EML of the emissive layer 920 in the third pixel region P3 of the red pixel region may include a first compound H as the main component, a second compound as a red delayed fluorescence material, and / or a third compound as a red fluorescent or phosphorescent material. In this case, each EML of the emissive layer 920 in the first pixel region P1, the second pixel region P2, and the third pixel region P3 may have a single-layer structure, a double-layer structure, or a triple-layer structure.

[0218] Alternatively, any EML in the light-emitting layer 920 of any of the first pixel region P1, the second pixel region P2, and the third pixel region P3 may contain organic compounds other than the first to third compounds.

[0219] An encapsulation film 870 can be disposed above the second electrode 930 to prevent external moisture from penetrating into the OLED D. The encapsulation film 870 may have a three-layer structure, including but not limited to a first inorganic insulating film, an organic insulating film, and a second inorganic insulating film.

[0220] A dam layer 860 is provided on the passivation layer 850 to cover the edge of the first electrode 910. Furthermore, the organic light-emitting display device 800 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 800 is a bottom-emitting type, the polarizer may be disposed below the substrate 810. Alternatively, when the organic light-emitting display device 800 is a top-emitting type, the polarizer may be disposed above the encapsulation film 870.

[0221] Figure 13 This is a schematic cross-sectional view of an OLED according to yet another exemplary aspect of this disclosure. Figure 13As shown, the OLED D6 includes a first electrode 910, a second electrode 930 facing the first electrode 910, and a light-emitting layer 920 disposed between the first electrode 910 and the second electrode 930.

[0222] The first electrode 910 can be an anode, and the second electrode 930 can be a cathode. As an example, the first electrode 910 can be a reflective electrode, and the second electrode 930 can be a transmissive (or semi-transmissive) electrode.

[0223] The light-emitting layer 920 includes an EML 940. The light-emitting layer 920 may include at least one of an HTL 960 disposed between the first electrode 910 and the EML 940 and an ETL 970 disposed between the second electrode 930 and the EML 940. Furthermore, the light-emitting layer may also include at least one of a HIL 950 disposed between the first electrode 910 and the HTL 960 and an EIL 980 disposed between the second electrode 930 and the ETL 970. Alternatively, the light-emitting layer 920 may also include an EBL 965 disposed between the HTL 960 and the EML 940 and / or an HBL 975 disposed between the EML 940 and the ETL 970.

[0224] Furthermore, the light-emitting layer 920 may also include an auxiliary hole transport layer (auxiliary HTL) 962 disposed between HTL 960 and EBL 965. The auxiliary HTL 962 may include a first auxiliary HTL 962a located in the first pixel region P1, a second auxiliary HTL 962b located in the second pixel region P2, and a third auxiliary HTL 962c located in the third pixel region P3.

[0225] The first auxiliary HTL 962a has a first thickness, the second auxiliary HTL 962b has a second thickness, and the third auxiliary HTL 962c has a third thickness. The first thickness is less than the second thickness, and the second thickness is less than the third thickness. Therefore, OLED D6 has a microcavity structure.

[0226] Because the first auxiliary HTL 962a, the second auxiliary HTL 962b, and the third auxiliary HTL 962c have different thicknesses, the distance between the first electrode 910 and the second electrode 930 in the first pixel region P1, which emits light (blue light) in the first wavelength range, is smaller than the distance between the first electrode 910 and the second electrode 930 in the second pixel region P2, which emits light (green light) in the second wavelength range. Furthermore, the distance between the first electrode 910 and the second electrode 930 in the second pixel region P2, which emits light in the second wavelength range, is smaller than the distance between the first electrode 910 and the second electrode 930 in the third pixel region P3, which emits light (red light) in the third wavelength range. Therefore, the OLED D6 has improved luminous efficiency.

[0227] exist Figure 13 In this configuration, the first auxiliary HTL 962a is located in the first pixel region P1. Alternatively, the OLED D6 can implement a microcavity structure without the first auxiliary HTL 962a. Furthermore, a capping layer can be disposed above the second electrode to improve the output coupling of light emitted from the OLED D6.

[0228] EML 940 includes a first EML (EML1) 942 located in the first pixel region P1, a second EML (EML2) 944 located in the second pixel region P2, and a third EML (EML3) 946 located in the third pixel region P3. EML1 942, EML2 944, and EML3 946 can each be a blue EML, a green EML, and a red EML, respectively.

[0229] In one exemplary aspect, EML1 942 located in the first pixel region P1 may comprise a first compound H as the main component, a second compound TD as a blue delayed fluorescent material, and / or a third compound FD as a blue fluorescent or phosphorescent material. EML2 944 located in the second pixel region P2 may comprise a first compound H as the main component, a second compound TD as a green delayed fluorescent material, and / or a third compound FD as a green fluorescent or phosphorescent material. EML3 946 located in the third pixel region P3 may comprise a first compound H as the main component, a second compound TD as a red delayed fluorescent material, and / or a third compound FD as a red fluorescent or phosphorescent material. The first compound H in EML1 942, EML2 944, and EML3 946 may be any organic compound having a structure having chemical formulas 1 to 3.

[0230] When EML1 942, EML2 944, and EML3 946 contain a first compound H, a second compound TD, and a third compound FD, the content of the first compound H can be greater than the content of the second compound TD, and the content of the second compound TD can be greater than the content of the third compound FD. In this case, exciton energy can be efficiently transferred from the second compound TD to the third compound FD. As an example, the contents of the first compound H, the second compound TD, and the third compound FD in each of EML1 942, EML2 944, and EML3 946 can each be, but not limited to, about 60% to about 75% by weight, about 20% to about 40% by weight, and about 0.1% to about 5% by weight, respectively.

[0231] Although Figure 13 Each of EML1 942, EML2 944, and EML3 946 has a single-layer structure, but each of EML1 942, EML2 944, and EML3 946 may each have a double-layer structure. Figure 7 or three-layer structure Figure 9 ).

[0232] In another exemplary aspect, at least one of EML1 942, EML2 944, and EML3 946 may comprise a first compound H, a second compound TD, and a third compound, while the remaining of EML1 942, EML2 944, and EML3 946 may comprise other organic compounds. In this case, EML1 942, EML2 944, and EML3 946 having the first to third compounds may have a monolayer, bilayer, or trilayer structure.

[0233] For example, the first EML1 942 located in the first pixel region P1 may comprise a first compound H as the host, a second compound TD as a blue delayed fluorescent material, and / or a third compound FD as a blue fluorescent or phosphorescent material. The EML2 944 located in the second pixel region P2 may comprise a host and a green dopant, and the EML3 946 located in the third pixel region P3 may comprise a host and a red dopant. The host of EML2 944 and / or EML3 944 may include the first compound H. Each of the green or red dopant may include at least one of a green or red phosphorescent material, a green or red fluorescent material, and a green or red delayed fluorescent material.

[0234] The OLED D6 emits blue, green, and red light in its first pixel region P1, second pixel region P2, and third pixel region P3, respectively, enabling the organic light-emitting display device 800 (… Figure 12 It can achieve full-color images.

[0235] The organic light-emitting display device 800 may further include color filter layers 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 layers may include a first color filter layer (blue color filter layer) corresponding to the first pixel region P1, a second color filter layer (green color filter layer) corresponding to the second pixel region P2, and a third color filter layer (red color filter layer) corresponding to the third pixel region P3.

[0236] When the organic light-emitting display device 800 is a bottom-emitting type, the color filter layer can be disposed between the OLED D and the substrate 810. Alternatively, when the organic light-emitting display device 800 is a top-emitting type, the color filter layer can be disposed above the OLED D.

[0237] Figure 14 This is a schematic cross-sectional view illustrating an organic light-emitting display device according to yet another exemplary aspect of this disclosure. Figure 14 As 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 and connected to the thin-film transistor Tr; and a color filter layer 1020 corresponding to the first pixel region P1, the second pixel region P2, and the third pixel region P3. As an example, the first pixel region P1 can be a blue pixel region, the second pixel region P2 can be a green pixel region, and the third pixel region P3 can be a red pixel region.

[0238] The substrate 1010 can be a glass substrate or a flexible substrate. For example, the flexible substrate can be any 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 can be disposed above the substrate 1010, and the thin-film transistor Tr can be disposed above the buffer layer. Figure 1 As shown, the thin-film transistor Tr includes a semiconductor layer, a gate electrode, a source electrode, and a drain electrode, and is used as a driving element.

[0239] 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 blue color filter layer, the second color filter layer 1024 may be a green color filter layer, and the third color filter layer 1026 may be a red color filter layer. For example, the first color filter layer 1022 may contain at least one of a blue dye or a blue pigment, the second color filter layer 1024 may contain at least one of a green dye or a green pigment, and the third color filter layer 1026 may contain at least one of a red dye or a red pigment.

[0240] A 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.

[0241] OLED D is disposed above passivation layer 1050 and corresponds to color filter layer 1020. OLED D includes a first electrode 1110 connected to the drain electrode of thin-film transistor Tr, a light-emitting layer 1120 and a second electrode 1130 respectively disposed sequentially on the first electrode 1110. OLED D emits white light in first pixel region P1, second pixel region P2 and third pixel region P3.

[0242] The first electrode 1110 is formed separately for each of the first pixel region P1, the second pixel region P2, and the third pixel region P3, while the second electrode 1130 corresponds to and is integrally formed with respect to the first pixel region P1, the second pixel region P2, and the third pixel region P3.

[0243] The first electrode 1110 can be either an anode or a cathode, and the second electrode 1130 can be either an anode or a cathode. Furthermore, the first electrode 1110 can be a transmitting (or semi-transmitting) electrode, and the second electrode 1130 can be a reflecting electrode.

[0244] For example, the first electrode 1110 can be an anode and may contain a conductive material with a relatively high work function value, i.e., a transparent conductive oxide layer of transparent conductive oxide (TCO). The second electrode 1130 can be a cathode and may contain a conductive material with a relatively low work function value, i.e., a metallic material layer of low-resistance metal. For example, the transparent conductive oxide layer of the first electrode 1110 may contain any one of ITO, IZO, ITZO, SnO, ZnO, ICO, and AZO, and the second electrode 1130 may contain Al, Mg, Ca, Ag, their alloys (e.g., Mg-Ag), or combinations thereof.

[0245] A 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 also include a CGL disposed between the light-emitting portions.

[0246] At least one of the at least two luminescent portions may contain a first compound H having a structure of chemical formulas 1 to 3 as the main component, a second compound TD as a delayed fluorescence material, and / or a third compound FD as a fluorescent or phosphorescent material.

[0247] A dam layer 1060 is disposed on the passivation layer 1050 to cover the edge of the first electrode 1110. The dam layer 1060 corresponds to each of the first pixel region P1, the second pixel region P2, and the third pixel region 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 can be formed as a common layer and is not separated in the first pixel region P1, the second pixel region P2, and the third pixel region P3. The dam layer 1060 is formed to prevent current leakage from the edge of the first electrode 1110, and the dam layer 1060 can be omitted.

[0248] Furthermore, the organic light-emitting display device 1000 may also include an encapsulation film disposed on the second electrode 1130 to prevent external moisture from penetrating into the OLED D. Additionally, the organic light-emitting display device 1000 may also include a polarizer disposed below the substrate 1010 to reduce external light reflection.

[0249] exist Figure 14 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 can be a reflective electrode, the second electrode 1130 can be a transmissive electrode (or a semi-transmissive electrode), and the color filter layer 1020 can be disposed above the OLED D.

[0250] In the organic light-emitting display device 1000, the OLED D located in the first pixel region P1, the second pixel region P2 and the third pixel region P3 emits white light. The white light passes through each of the first pixel region P1, the second pixel region P2 and the third pixel region P3, so that blue, green and red are displayed in the first pixel region P1, the second pixel region P2 and the third pixel region P3 respectively.

[0251] A color conversion film can be disposed between the OLED D and the color filter layer 1020. The color conversion film corresponds to the first pixel region P1, the second pixel region P2, and the third pixel region P3, and includes a blue conversion film, a green conversion film, and a red conversion film, respectively, which can convert white light emitted from the OLED D into blue light, green light, and red light. For example, the color conversion film can contain quantum dots. Therefore, the organic light-emitting display device 1000 can further enhance its color purity. Alternatively, the color conversion film can replace the color filter layer 1020.

[0252] Figure 15 This is a schematic cross-sectional view of an OLED according to yet another exemplary aspect of this disclosure. Figure 15 As shown, the OLED D7 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 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.

[0253] 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. Furthermore, the light-emitting layer 1120 may also include a first charge-generating layer (CGL1) 1280 disposed between the first light-emitting portion 1220 and the second light-emitting portion 1320, and a second charge-generating layer (CGL2) 1380 disposed between the second light-emitting portion 1320 and the third light-emitting portion 1420. Therefore, 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.

[0254] The first light-emitting portion 1220 may further include at least one of the following: a first HTL (HTL1) 1260 disposed between the first electrode 1110 and EML1 1240, a HIL 1250 disposed between the first electrode 1110 and HTL1 1260, and a first ETL (ETL1) 1270 disposed between EML1 1240 and CGL1 11280. Alternatively, the first light-emitting portion 1220 may further include a first EBL (EBL1) 1265 disposed between HTL1 1260 and EML1 1240 and / or a first HBL (HBL1) 1275 disposed between EML1 1240 and ETL1 1270.

[0255] The second light-emitting portion 1320 may further include at least one of a second HTL (HTL2) 1360 disposed between CGL1 1280 and EML2 1340, and a second ETL (ETL2) 1370 disposed between EML2 1340 and CGL2 1380. Alternatively, the second light-emitting portion 1320 may further include a second EBL (EBL2) 1365 disposed between HTL2 1360 and EML2 1340 and / or a second HBL (HBL2) 1375 disposed between EML2 1340 and ETL2 1370.

[0256] The third light-emitting portion 1420 may further include at least one of the following: a third HTL (HTL3) 1460 disposed between CGL2 1380 and EML3 1440; a third ETL (ETL3) 1470 disposed between EML3 1440 and the second electrode 1130; and an EIL 1480 disposed between ETL3 1470 and the second electrode 1130. Alternatively, the third light-emitting portion 1420 may further include a third EBL (EBL3) 1465 disposed between HTL3 1460 and EML3 1440 and / or a third HBL (HBL3) 1475 disposed between EML3 1440 and ETL3 1470.

[0257] CGL1 1280 is disposed between the first light-emitting portion 1220 and the second light-emitting portion 1320. That is, the first light-emitting portion 1220 and the second light-emitting portion 1320 are connected via CGL1 1280. CGL1 1280 can be a PN junction CGL that connects the first N-type CGL (N-CGL1) 1282 and the first P-type CGL (P-CGL1) 1284.

[0258] N-CGL1 1282 is disposed between ETL1 1270 and HTL2 1360, and P-CGL1 1284 is disposed between N-CGL1 1282 and HTL2 1360. N-CGL1 1282 transfers electrons to EML1 1240 of the first light-emitting part 1220, while P-CGL1 1284 transfers holes to EML2 1340 of the second light-emitting part 1320.

[0259] CGL2 1380 is disposed between the second light-emitting portion 1320 and the third light-emitting portion 1420. That is, the second light-emitting portion 1320 and the third light-emitting portion 1420 are connected via CGL2 1380. CGL2 1380 can be a PN junction CGL that connects the second N-type CGL (N-CGL2) 1382 and the second P-type CGL (P-CGL2) 1384.

[0260] N-CGL2 1382 is disposed between ETL2 1370 and HTL3 1460, and P-CGL2 1384 is disposed between N-CGL2 1382 and HTL3 1460. N-CGL2 1382 transfers electrons to EML2 1340 of the second light-emitting portion 1320, while P-CGL2 1384 transfers holes to EML3 1440 of the third light-emitting portion 1420. In one exemplary aspect, at least one of N-CGL1 1282 and N-CGL2 1382 may comprise any organic compound having a structure having chemical formulas 1 to 3.

[0261] In this respect, one of the first EML 1240, the second EML 1340 and the third EML 1440 can be a blue EML, another of the first EML 1240, the second EML 1340 and the third EML 1440 can be a green EML, and the third of the first EML 1240, the second EML 1340 and the third EML 1440 can be a red EML.

[0262] As an example, EML1 1240 can be a blue EML, EML2 1340 can be a green EML, and EML3 1440 can be a red EML. Alternatively, EML1 1240 can be a red EML, EML2 1340 can be a green EML, and EML3 1440 can be a blue EML. The following description will focus on an OLED D7 where EML1 1240 is a blue EML, EML2 1340 is a green EML, and EML3 1440 is a red EML.

[0263] As described below, at least one of EML1 1240, EML2 1340, and EML3 1440 may contain a first compound H, a second compound TD, and / or a third compound FD. EML1240, 1340, and 1440 containing the first to third compounds may have a monolayer, bilayer, or trilayer structure.

[0264] EML1 1240 may comprise a first compound H, which may be an organic compound having a structure having chemical formulas 1 to 3, a second compound TD, which is a blue delayed fluorescence material, and / or a third compound FD, which is a blue fluorescent or phosphorescent material. Alternatively, EML1 1240 may comprise a host and other blue dopants. The host may include the first compound, and the other blue dopants may include at least one of a blue phosphorescent material, a blue fluorescent material, and a blue delayed fluorescence material.

[0265] EML2 1340 may comprise a first compound H, which may be an organic compound having a structure having chemical formulas 1 to 3, a second compound TD, which is a green delayed fluorescence material, and / or a third compound FD, which is a green fluorescent or phosphorescent material. Alternatively, EML2 1340 may comprise a host and other green dopants. The host may include the first compound, and the other green dopants may include at least one of green phosphorescent materials, green fluorescent materials, and green delayed fluorescence materials.

[0266] EML3 1440 may comprise a first compound H, which may be an organic compound having a structure of chemical formulas 1 to 3, a second compound TD, which is a red delayed fluorescence material, and / or a third compound FD, which is a red fluorescent or phosphorescent material. Alternatively, EML3 1440 may comprise a host and other red dopants. The host may include the first compound, and the other red dopants may include at least one of a red phosphorescent material, a red fluorescent material, and a red delayed fluorescence material.

[0267] When EML1 1240, EML2 1340, and EML3 1440 each contain a first compound H, a second compound TD, and a third compound FD, the content of the first compound H can be greater than the content of the second compound TD, and the content of the second compound TD can be greater than the content of the third compound FD. In this case, exciton energy can be efficiently transferred from the second compound TD to the third compound FD. As an example, the contents of the first compound H, the second compound TD, and the third compound FD in each of EML1 1240, EML2 1340, and EML3 1440 can each be, but not limited to, about 60% to about 75% by weight, about 20% to about 40% by weight, and about 0.1% to about 5% by weight, respectively.

[0268] The OLED D7 emits white light from each of the first pixel region P1, the second pixel region P2, and the third pixel region P3. The white light passes through color filter layers 1020 correspondingly disposed in the first pixel region P1, the second pixel region P2, and the third pixel region P3. Figure 14 Therefore, the OLED D7 can achieve full-color images.

[0269] Figure 16 This is a schematic cross-sectional view of an OLED according to yet another exemplary aspect of this disclosure. Figure 16 As shown, the OLED D8 includes a first electrode 1110 and a second electrode 1130 facing each other, and a light-emitting layer 1120A disposed 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.

[0270] 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 EML1 1540, the second light-emitting portion 1620 includes EML2 1640, and the third light-emitting portion 1720 includes EML3 1740. Furthermore, the light-emitting layer 1120A may also include CGL1 1580 disposed between the first light-emitting portion 1520 and the second light-emitting portion 1620, and CGL2 1680 disposed between the second light-emitting portion 1620 and the third light-emitting portion 1720. Therefore, the first light-emitting portion 1520, CGL1 1580, the second light-emitting portion 1620, CGL2 1680, and the third light-emitting portion 1720 are sequentially disposed on the first electrode 1110.

[0271] The first light-emitting portion 1520 may further include at least one of HTL11560 disposed between the first electrode 1110 and EML1 1540, HIL 1550 disposed between the first electrode 1110 and HTL1 1560, and ETL1 1570 disposed between EML1 1540 and CGL1 1580. Alternatively, the first light-emitting portion 1520 may further include EBL1 1565 disposed between HTL1 1560 and EML1 1540 and / or HBL1 1575 disposed between EML1 1540 and ETL1 1570.

[0272] The second light-emitting portion 1620 includes a lower EML 1642 and an upper EML 1644 in its EML2 1640. 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. Furthermore, the second light-emitting portion 1620 may also include at least one of an HTL2 1660 disposed between CGL1 1580 and EML2 1640, and an ETL2 1670 disposed between EML2 1640 and CGL2 1680. Alternatively, the second light-emitting portion 1620 may also include an EBL2 1665 disposed between HTL2 1660 and EML2 1640 and / or an HBL2 1675 disposed between EML2 1640 and ETL2 1670.

[0273] The third light-emitting portion 1720 may further include at least one of HTL3 1760 disposed between CGL2 1680 and EML3 1740, ETL3 1770 disposed between EML3 1740 and the second electrode 1130, and EIL 1780 disposed between ETL3 1770 and the second electrode 1130. Alternatively, the third light-emitting portion 1720 may further include EBL3 1765 disposed between HTL3 1760 and EML3 1740 and / or HBL3 1775 disposed between EML3 1740 and ETL3 1770.

[0274] CGL1 1580 is disposed between the first light-emitting portion 1520 and the second light-emitting portion 1620. That is, the first light-emitting portion 1520 and the second light-emitting portion 1620 are connected via CGL1 1580. CGL1 1580 can be a PN junction CGL that connects N-CGL1 1582 and P-CGL1 1584. N-CGL1 1582 is disposed between ETL1 1570 and HTL2 1660, and P-CGL1 1584 is disposed between N-CGL1 1582 and HTL2 1660.

[0275] CGL2 1680 is disposed between the second light-emitting portion 1620 and the third light-emitting portion 1720. That is, the second light-emitting portion 1620 and the third light-emitting portion 1720 are connected via CGL2 1680. CGL2 1680 can be a PN junction CGL connecting 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 may comprise any organic compound having a structure having chemical formulas 1 to 3.

[0276] As described below, at least one of EML1 1540, EML2 1640, and EML3 1740 may contain a first compound H, a second compound TD, and / or a third compound FD. EMLs 1540, 1640, and 1740 containing the first to third compounds may have a monolayer, bilayer, or trilayer structure.

[0277] In this aspect, each of EML1 1540 and EML3 1740 may be a blue EML. In one exemplary aspect, each of EML1 1540 and EML3 1740 may comprise a first compound H as the host and a second compound TD as a blue delayed fluorescence material and / or a third compound FD as a blue fluorescent or phosphorescent material. Alternatively, at least one of EML1 1540 and EML3 1740 may comprise a host and other blue dopants. The host may comprise the first compound, and the other blue dopants may comprise at least one of blue phosphorescent material, blue fluorescent material, and blue delayed fluorescence material. The first to third compounds in one of EML1 1540 and EML3 1740 may be the same as or different from the host and blue dopants in the other of EML1 1540 and EML3 1740. As an example, the dopants in EML1 1540 may differ from those in EML3 1740 in terms of luminous efficiency and / or emission wavelength.

[0278] In EML2 1640, one of the lower EML 1642 and the upper EML 1644 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 set sequentially to form EML2 1640.

[0279] In one exemplary aspect, the lower EML 1642, as a green EML, may comprise a first compound H as the host, a second compound TD as a green delayed fluorescence material, and / or a third compound FD as a green fluorescent or phosphorescent material. Alternatively, the lower EML 1642, as a green EML, may comprise a host and other green dopants. The host may include the first compound H, and the other green dopants may include at least one of a green phosphorescent material, a green fluorescent material, and a green delayed fluorescence material.

[0280] Furthermore, the upper EML 1644 as a red EML may comprise a first compound H as the host, a second compound TD as a red delayed fluorescence material, and / or a third compound FD as a red fluorescent or phosphorescent material. Alternatively, the upper EML 1644 as a red EML may comprise a host and other red dopants. The host may include the first compound H, and the other red dopants may include at least one of a red phosphorescent material, a red fluorescent material, and a red delayed fluorescence material.

[0281] When EML1 1540, EML2 1640, and EML3 1740 each contain a first compound H, a second compound TD, and a third compound FD, the content of the first compound H can be greater than the content of the second compound TD, and the content of the second compound TD can be greater than the content of the third compound FD. In this case, exciton energy can be efficiently transferred from the second compound TD to the third compound FD. As an example, the contents of the first compound H, the second compound TD, and the third compound FD in each of EML1 1540, EML2 1640, and EML3 1740 can each be, but not limited to, about 60% to about 75% by weight, about 20% to about 40% by weight, and about 0.1% to about 5% by weight, respectively.

[0282] The OLED D8 emits white light from each of the first pixel region P1, the second pixel region P2, and the third pixel region P3. The white light passes through color filter layers 1020 correspondingly disposed in the first pixel region P1, the second pixel region P2, and the third pixel region P3. Figure 14 Therefore, the OLED D8 can achieve full-color images.

[0283] exist Figure 16In this embodiment, the OLED D8 has a triple-stacked structure comprising first to third light-emitting portions 1520, 1620, and 1720, wherein the first to third light-emitting portions 1520, 1620, and 1720 include EML11540 and EML31740 as blue EMLs. Alternatively, the OLED D8 may have a double-stacked structure, wherein one of the first light-emitting portion 1520 and the third light-emitting portion 1720, each including EML11540 and EML31740 as blue EMLs, is omitted.

[0284] Synthesis Example 1: Synthesis of Compound 1-1

[0285] (1) Synthesis of intermediate B

[0286]

[0287] Compound A (4.48 g, 0.013 mol), carbazole (2.0 g, 0.012 mol), and K3PO4 dissolved in toluene (60 mL) were added to a reactor, and the solution was stirred under a nitrogen atmosphere for 20 minutes. CuI (460 mg, 20 mol%) and (±)-trans-1,2-diaminocyclohexane (DACH, 0.72 mL, 50 mol%) were added to the reactor, and the solution was stirred at 110 °C for 8 hours. After cooling to room temperature, the reaction solvent was removed, and the crude product was purified by column chromatography to give a white solid intermediate B (1.9 g, yield: 42%).

[0288]

[0289] (2) Synthesis of intermediate c

[0290]

[0291] Under a nitrogen atmosphere, 0.22 g (0.006 mol) of LiAlH4 dissolved in 10 mL of THF was added to a reactor, and the solution was then cooled to 0 °C. Intermediate B (2.0 g (0.005 mol)) dissolved in 15 mL of THF was slowly added dropwise to the solution. After stirring at the same temperature for 20 minutes, the solution was extracted with ethyl acetate to remove the solvent. The obtained crude product was purified by column chromatography to give intermediate C (1.7 g, yield: 92%), a white solid.

[0292]

[0293] (3) Synthesis of intermediate D

[0294]

[0295] Intermediate C (1.8 g, 0.005 mol) dissolved in dichloromethane (15 mL) and KOH (2.3 g, 0.041 mol) were added to a reactor, and the temperature was cooled to 0 °C with stirring. p-Toluenesulfonyl chloride (1.17 g, 0.006 mol) dissolved in dichloromethane (10 mL) was slowly added dropwise to the reaction solution. After stirring at the same temperature for 20 minutes, the reaction mixture was stirred again at room temperature for 4 hours, and then extracted with CH₂Cl₂ to remove the solvent. The obtained product was purified by column chromatography to give intermediate D (2.2 g, yield: 85%) as a white solid.

[0296]

[0297] (4) Synthesis of compound 1-1

[0298]

[0299] 1H-benzo[d]imidazol-2-thiol (0.5 g, 0.003 mol), CuI (63 mg, 10 mol%), and Cs₂CO₃ (2.17 g, 0.007 mol), dissolved in DMF (20 mL), were added to a reactor, and the solution was stirred under a nitrogen atmosphere for 20 minutes. Intermediate D (1.68 g, 0.003 mol) and L-proline (77 mg, 20 mol%), dissolved in DMF (20 mL), were slowly added dropwise to the reaction solution. After stirring at 160 °C for 8 hours, the reactor was cooled to room temperature, and the solution was extracted with EtOAc to remove the solvent. The obtained crude product was purified by column chromatography to give a white solid compound 1-1 (1.2 g, yield: 89%).

[0300]

[0301] Synthesis Example 2: Synthesis of Compounds 1-2

[0302] (1) Synthesis of intermediate E

[0303]

[0304] Compound A (4.50 g, 0.013 mol) and 9H-3,9'-bicarbazole (4.0 g, 0.012 mol) were reacted in the same manner as the synthesis of intermediate B to finally give white solid intermediate E (3.0 g, yield: 46%).

[0305]

[0306] (2) Synthesis of intermediate F

[0307]

[0308] Intermediate E (2.0 g, 0.004 mol) was used in the same manner as intermediate C to finally give white solid intermediate F (1.6 g, yield: 84%).

[0309]

[0310] (3) Synthesis of intermediate G

[0311]

[0312] Intermediate F (2.2 g, 0.004 mol) was used in the same manner as intermediate D to finally give white solid intermediate G (2.5 g, yield: 88%).

[0313]

[0314] (4) Synthesis of compounds 1-2

[0315]

[0316] 1H-benzo[d]imidazol-2-thiol (0.5 g, 0.003 mol) and intermediate G (2.23 g, 0.003 mol) were reacted in the same manner as the synthesis of compound 1-1 to finally give compound 1-2 (1.6 g, yield: 85%), a white solid.

[0317]

[0318] Synthesis Example 3: Synthesis of Compounds 2-5

[0319] (1) Synthesis of intermediate I

[0320]

[0321] Compound H (10.0 g, 0.031 mol), 1H-benzo[d]imidazol-2-thiol (4.6 g, 0.031 mol), FeCl3 (0.5 g, 0.003 mol), and Cs2CO3 (20 g, 0.061 mol), dissolved in DMF (60 mL), were added to a reactor under a nitrogen atmosphere. After stirring the solution at 160 °C for 24 hours, AcOH (10 mL) was added dropwise to the solution, and the solution was stirred at the same temperature for 2 hours. The reactor was cooled to room temperature, and the solution was extracted with dichloromethane to remove the solvent. The obtained crude product was purified by column chromatography to give intermediate I (6.0 g, yield: 59%), a white solid.

[0322]

[0323] (2) Synthesis of intermediate J

[0324]

[0325] Intermediate I (0.6 g, 0.0018 mol), carbazole (0.36 g, 0.0022 mol), and K₂CO₃ dissolved in toluene (30 mL) were added to a reactor, and the solution was stirred for 30 minutes under a nitrogen atmosphere. Tris(dibenzylacetone)dipalladium(0) (Pd₂(dba)₃, 7.2 mg, 2 mol%) and tri-tert-butylphosphine (4.4 mg, 4 mol%) were added to the reactor, and the solution was stirred at 110 °C for 24 hours. After cooling to room temperature, the reaction solvent was removed, and the crude product was purified by column chromatography to give intermediate J (0.26 g, yield: 35%), a white solid.

[0326]

[0327] (3) Synthesis of compounds 2-5

[0328]

[0329] Intermediate J (0.39 g, 0.93 mmol) dissolved in THF (60 mL) was placed into a reactor under a nitrogen atmosphere, and the solution was then cooled to -78 °C. 1.0 M phenylmagnesium bromide (PhMgBr, 3.75 mL) was slowly added dropwise to the reaction solution. After stirring at room temperature for 6 hours, the solution was extracted with diethyl ether to remove the solvent. The reaction mixture was dissolved in CH3COOH (10 mL), and then HCl (2 mL) was slowly added dropwise to the mixture. The solution was stirred at room temperature for 1 hour, neutralized with an aqueous solution of NaHCO3, and then extracted with CH2Cl2. After solvent removal, the obtained crude product was purified by column chromatography to give a white solid compound 2-5 (0.2 g, yield: 40%).

[0330]

[0331] Synthesis Example 4: Synthesis of Compound 2-17

[0332] (1) Synthesis of intermediate K

[0333]

[0334] Intermediate I (0.6 g, 0.0018 mol) and 9,9-diphenylacridine (0.73 g, 0.0022 mol) were reacted in the same manner as the synthesis of intermediate J to finally give intermediate K (0.44 g, yield: 42%), a white solid.

[0335] (2) Synthesis of compound 2-17

[0336]

[0337] Intermediate K (0.44 g, 0.75 mol) and 1.0 M PhMgBr (3.0 mL) were reacted in the same manner as in the synthesis of compounds 2-5 to finally give compound 2-17 (0.26 g, yield: 48%), a white solid.

[0338] Experimental Example 1: Measurement of Energy Levels

[0339] The HOMO level, LUMO level, and band gap (E) between the HOMO and LUMO levels of the compounds synthesized in the synthesis examples were evaluated. g The simulation results are shown in Table 1 below, and the experimental results for the coated thin film in solution state are shown in Table 2 below.

[0340] Table 1: Energy Level Simulation Test (DFT Calculation)

[0341] Transform an object HOMO(eV) LUMO(eV) Eg(eV) [S1 (eV)] <![CDATA[T1(eV)]]> 1-1 -5.53 -1.16 4.37 3.81 3.18 1-2 -5.23 -1.30 3.93 3.55 3.15 2-5 -5.49 -0.94 3.55 3.93 3.18 2-17 -5.17 -0.94 4.23 3.50 3.33

[0342] Table 2: Energy Levels of Organic Compounds

[0343]

[0344] As shown in Tables 1 and 2, all the organic compounds synthesized in the examples possess suitable HOMO, LUMO, band gaps, and excited singlet and triplet energies for the emitting layer. In particular, considering the band gap between S1 and T1, the organic compounds exhibit very high excited triplet energy levels and are suitable as the host in EML and as materials for ETL and HBL. Furthermore, all compounds emit light within the blue wavelength band.

[0345] Example 1: OLED Manufacturing

[0346] An OLED is fabricated in which compound 1-1 is applied to the body of an EML. A glass substrate with attached ITO is washed with UV ozone, loaded into a vapor system, and then transferred to a vacuum deposition chamber to deposit other layers on the substrate. The following steps are performed in sequence: The deposition rate is at 10 -7 An organic layer is deposited by vapor deposition on a heated vessel.

[0347] Anode (ITO, 50 nm); HIL (HAT-CN, 7 nm); HTL (TAPC, 50 nm); EBL (DCDPA, 10 nm); EML (compound 1-1 (body): blue delayed fluorescent material TczTrz (dopant) = 70:30, 30 nm by weight); HBL (TSPO1, 5 nm); ETL (TPBi, 25 nm); EIL (LiF, 1.5 nm); and cathode (Al, 100 nm).

[0348] Next, a capping layer (CPL) is deposited over the cathode, and the device is encapsulated with glass. After depositing the light-emitting layer and the cathode, the OLED is transferred from the deposition chamber to a drying oven for film formation, and then encapsulated using a UV-curable epoxy resin and a desiccant.

[0349] Examples 2 to 3 (Ex.2 to Ex.3): OLED fabrication The OLED was manufactured using the same materials as in Example 1, except that compounds 1-2 (Ex.2) or 2-5 (Ex.3) were applied to the EML as the host instead of compound 1-1.

[0350] Comparative Example 1 (Ref. 1): OLED Manufacturing

[0351] The OLED was fabricated using the same materials as in Example 1, except that mCBP (Ref. 1) was applied to the EML as the host instead of compound 1-1.

[0352] Experiment Example 2: Measurement of the luminescent properties of OLED

[0353] The 9mm diameter will be manufactured through Ex.1 to Ex.3 and Ref.1. 2 Each OLED with a light-emitting area was connected to an external power supply, and the light-emitting characteristics of all diodes were evaluated at room temperature using a constant current source (KEITHLEY) and a PR650 photometer. Specifically, measurements were taken at 10 mA / cm². 2 Drive voltage (V), current efficiency (cd / A), power efficiency (lm / W), external quantum efficiency (EQE, %), and maximum EQE (EQE) at current density. max The results are shown in Table 3 below.

[0354] Table 3: Luminescent properties of OLEDs

[0355] sample main body V cd / A lm / W EQE <![CDATA[EQE max ]]> CIE(x, y) Ref.1 mCBP 4.0 25.8 20.4 14.7 22.8 (0.162，0.289) Ex1 1-1 4.1 27.5 21.2 15.3 23.0 (0.163，0.298) Ex2 1-2 42 27.0 19.5 15.0 23.8 (0.164，0.299) Ex3 2-5 3.7 30.1 25.8 15.7 22.0 (0.170，0.333)

[0356] As shown in Table 3, compared with the OLED in Ref.1 which uses mCBP as the main body, the OLEDs in Ex.1 to Ex.3 show comparable or slightly lower driving voltages, but enhance their current efficiency, power efficiency and EQE by 16.7%, 26.5% and 6.8%, respectively.

[0357] The following scheme is disclosed in this disclosure:

[0358] 1. An organic compound having the structure of the following chemical formula 1:

[0359] [Chemical Formula 1]

[0360]

[0361] Wherein R1 is an unsubstituted or substituted fused heteroaromatic group having 3 to 6 aromatic rings or heteroaromatic rings and having 1 to 3 nitrogen atoms, or an unsubstituted or substituted C6-C group. 30 Aromatic amino groups, or unsubstituted or substituted C4-C 30 Mixed aromatic amino groups;

[0362] R2 and R3 are each independently selected from hydrogen, unsubstituted or substituted C1-C. 30 Alkyl, unsubstituted or substituted C6-C 30 Aromatic groups and unsubstituted or substituted C3-C 30 A heteroaromatic group, wherein each of R2 and R3 is the same as or different from each other when a and b are each independently an integer of 2 or greater; a and b are each independently the number of substituents, where a is an integer from 0 to 3 and b is an integer from 0 to 4; X and Y are each independently CR4R5.

[0363] R4 and R5 are each independently selected from hydrogen, unsubstituted or substituted C1-C. 30 Alkyl, unsubstituted or substituted C6-C 30 Aromatic groups and unsubstituted or substituted C3-C 30 heteroaromatic groups, or R4 and R5 forming C6-C 20 Aroma rings or C3-C 20 A heteroaryromatic ring; m and n are each 0 or 1, where m + n = 1; Z is S, O, or NR6, and

[0364] R6 is selected from hydrogen, unsubstituted or substituted C1-C. 30 Alkyl, unsubstituted or substituted C6-C 30 Aromatic groups and unsubstituted or substituted C3-C 30 Mixed aromatic groups.

[0365] 2. The organic compound according to claim 1, wherein the fused heteroaromatic group is unsubstituted and selected from C1-C2. 20 Alkyl, C6-C 20 Aryl, C3-C 20 The heteroaryl group and its combination are substituted with groups, or form a spirocyclic structure with a fluorene ring or a zeolite ring.

[0366] 3. The organic compound according to claim 1, wherein the fused heteroaromatic group is selected from the carbazoyl moiety, acridine moiety, dihydroacridyl moiety, phenazinyl moiety, and phenazinyl moiety. Azine moiety.

[0367] 4. The organic compound according to claim 1, wherein the fused heteroaromatic group is unsubstituted or selected from C1-C2. 10 Alkyl, phenyl, carbazole, or combinations thereof substitution, or the formation of a spirocyclic structure with a zeolite ring, and R4 and R5 are either unsubstituted or selected from C1-C2. 10 Alkyl, phenyl, and combinations thereof are substituted, or R4 and R5 form a fluorene ring.

[0368] 5. The organic compound according to item 1, wherein Z is S.

[0369] 6. The organic compound according to claim 1, wherein the organic compound includes any of those having a structure of chemical formula 2 as described in the specification.

[0370] 7. The organic compound according to claim 1, wherein the organic compound includes any of those having a structure of chemical formula 3 as described in the specification.

[0371] 8. An organic light-emitting diode, comprising:

[0372] First electrode;

[0373] The second electrode facing the first electrode; and

[0374] A light-emitting layer disposed between the first electrode and the second electrode.

[0375] The light-emitting layer comprises an organic compound having the structure of the following chemical formula 1:

[0376] [Chemical Formula 1]

[0377]

[0378] Wherein R1 is an unsubstituted or substituted fused heteroaromatic group having 3 to 6 aromatic rings or heteroaromatic rings and having 1 to 3 nitrogen atoms, or an unsubstituted or substituted C6-C group. 30 Aromatic amino groups, or unsubstituted or substituted C4-C30 Mixed aromatic amino groups;

[0379] R2 and R3 are each independently selected from hydrogen, unsubstituted or substituted C1-C. 30 Alkyl, unsubstituted or substituted C6-C 30 Aromatic groups and unsubstituted or substituted C3-C 30 A heteroaromatic group, wherein each of R2 and R3 is the same as or different from each other when a and b are each independently an integer of 2 or greater; a and b are each independently the number of substituents, where a is an integer from 0 to 3 and b is an integer from 0 to 4; X and Y are each independently CR4R5.

[0380] R4 and R5 are each independently selected from hydrogen, unsubstituted or substituted C1-C. 30 Alkyl, unsubstituted or substituted C6-C 30 Aromatic groups and unsubstituted or substituted C3-C 30 heteroaromatic groups, or R4 and R5 forming C6-C 20 Aroma rings or C3-C 20 A heteroaryromatic ring; m and n are each 0 or 1, where m + n = 1; Z is S, O, or NR6, and

[0381] R6 is selected from hydrogen, unsubstituted or substituted C1-C. 30 Alkyl, unsubstituted or substituted C6-C 30 Aromatic groups and unsubstituted or substituted C3-C 30 Mixed aromatic groups.

[0382] 9. The organic light-emitting diode according to claim 8, wherein the fused heteroaromatic group is unsubstituted and selected from C1-C1. 20 Alkyl, C6-C 20 Aryl, C3-C 20 The heteroaryl group and its combination are substituted with groups, or form a spirocyclic structure with a fluorene ring or a zeolite ring.

[0383] 10. The organic light-emitting diode according to claim 8, wherein the fused heteroaromatic group is selected from carbazole moiety, acridine moiety, dihydroacridinyl moiety, phenazinyl moiety, and phenazinyl moiety. Azine moiety.

[0384] 11. The organic light-emitting diode according to claim 8, wherein the fused heteroaromatic group is unsubstituted or selected from C1-C14. 10 Alkyl, phenyl, and carbazole groups and combinations thereof, or groups that form a spirocyclic structure with a zeolite ring, and R4 and R5 are either unsubstituted or selected from C1-C2. 10Alkyl, phenyl, and combinations thereof are substituted, or R4 and R5 form a fluorene ring.

[0385] 12. The organic light-emitting diode according to claim 8, wherein the light-emitting layer includes at least one electron transport layer disposed between the first electrode and the second electrode, and wherein the at least one electron transport layer comprises the organic compound.

[0386] 13. The organic light-emitting diode according to claim 8, wherein the light-emitting layer includes at least one hole-blocking layer disposed between the first electrode and the second electrode, and wherein the at least one hole-blocking layer comprises the organic compound.

[0387] 14. The organic light-emitting diode according to claim 8, wherein the light-emitting layer includes a first light-emitting material layer disposed between the first electrode and the second electrode, and wherein the first light-emitting material layer contains the organic compound.

[0388] 15. The organic light-emitting diode according to claim 14, wherein the first light-emitting material layer comprises a first compound and a second compound, wherein the excited triplet energy level of the first compound is higher than the excited triplet energy level of the second compound, and wherein the first compound comprises the organic compound.

[0389] 16. The organic light-emitting diode according to claim 15, wherein the first light-emitting material layer further comprises a third compound.

[0390] 17. The organic light-emitting diode according to claim 16, wherein the excited singlet state energy level of the third compound is lower than that of the excited singlet state energy level of the second compound.

[0391] 18. The organic light-emitting diode according to claim 15 further includes 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.

[0392] The second luminescent material layer contains a fourth compound and a fifth compound.

[0393] 19. The organic light-emitting diode according to claim 18, wherein the fourth compound comprises the organic compound.

[0394] 20. The organic light-emitting diode according to claim 18 further includes a third light-emitting material layer disposed opposite to the second light-emitting material layer relative to the first light-emitting material layer.

[0395] The third luminescent material layer contains a sixth compound and a seventh compound.

[0396] 21. The organic light-emitting diode according to claim 20, wherein at least one of the fourth compound and the sixth compound comprises the organic compound.

[0397] 22. The organic light-emitting diode according to claim 8, wherein the light-emitting layer comprises a first light-emitting unit disposed between the first electrode and the second electrode, a second light-emitting unit disposed between the first light-emitting unit and the second electrode, and a charge-generating layer disposed between the first light-emitting unit and the second light-emitting unit, and

[0398] At least one of the first light-emitting unit and the second light-emitting unit contains the organic compound.

[0399] 23. An organic light-emitting device, comprising:

[0400] Substrate; and

[0401] An organic light-emitting diode according to any one of items 8 to 22 is disposed above the substrate.

[0402] It will be apparent to those skilled in the art that various modifications and variations can be made to this disclosure without departing from its scope. Therefore, this disclosure is intended to cover any modifications and variations thereof that fall within the scope of the appended claims.

Claims

1. An organic compound having the structure of the following chemical formula 1: [Chemical Formula 1] Wherein R1 is a fused heteroaromatic group, wherein the fused heteroaromatic group is selected from carbazolyl, acridinel, dihydroacridyl, phenazinyl, and phenanthrene moieties. The azinoyl moiety, wherein the fused heteroaromatic group is unsubstituted and selected from C1-C1, is... 20 Alkyl, C6-C 20 Aryl, C3-C 20 Group substitution of heteroaryl groups and combinations thereof, or formation of spirocyclic structures with fluorene or xanthine rings; R2 and R3 are each independently selected from hydrogen, C1-C 30 Alkyl, C6-C 30 Aromatic groups and C3-C 30 A heteroaromatic group, wherein each of R2 and R3 is the same as or different from each other when a and b are each independently an integer of 2 or greater; a and b are each independently the number of substituents, where a is an integer from 0 to 3 and b is an integer from 0 to 4; X and Y are each independently CR4R5. R4 and R5 are each independently selected from hydrogen, C1-C 30 Alkyl and C6-C 30 Aryl; m is 0; n is 1; and Z is S or O.

2. The organic compound according to claim 1, wherein the fused heteroaromatic group is unsubstituted or selected from C1-C6. 10 Alkyl, phenyl, carbazolyl, and combinations thereof are substituted, or a spirocyclic structure is formed with a zeolite ring, and R4 and R5 are each hydrogen, C1 alkyl, or C6 aryl.

3. The organic compound according to claim 1, wherein Z is S.

4. An organic compound selected from those having a structure of chemical formula 3: [Chemical Formula 3] 5. An organic light-emitting diode, comprising: First electrode; The second electrode facing the first electrode; as well as A light-emitting layer disposed between the first electrode and the second electrode. The light-emitting layer comprises an organic compound having the structure of the following chemical formula 1: [Chemical Formula 1] Wherein R1 is a fused heteroaromatic group, wherein the fused heteroaromatic group is selected from carbazolyl, acridinel, dihydroacridyl, phenazinyl, and phenanthrene moieties. The azinoyl moiety, wherein the fused heteroaromatic group is unsubstituted and selected from C1-C1, is... 20 Alkyl, C6-C 20 Aryl, C3-C 20 Group substitution of heteroaryl groups and combinations thereof, or formation of spirocyclic structures with fluorene or xanthine rings; R2 and R3 are each independently selected from hydrogen, C1-C 30 Alkyl, C6-C 30 Aromatic groups and C3-C 30 A heteroaromatic group, wherein each of R2 and R3 is the same as or different from each other when a and b are each independently an integer of 2 or greater; a and b are each independently the number of substituents, where a is an integer from 0 to 3 and b is an integer from 0 to 4; X and Y are each independently CR4R5. R4 and R5 are each independently selected from hydrogen, C1-C 30 Alkyl and C6-C 30 Aryl; m is 0; n is 1; and Z is S or O.

6. The organic light-emitting diode according to claim 5, wherein the fused heteroaromatic group is unsubstituted or selected from C1-C1. 10 Alkyl, phenyl, and carbazole groups and combinations thereof, or forming a spirocyclic structure with a zeolite ring, and R4 and R5 are each hydrogen, C1 alkyl, or C6 aryl.

7. The organic light-emitting diode according to claim 5, wherein the light-emitting layer includes a first light-emitting material layer disposed between the first electrode and the second electrode, and wherein the first light-emitting material layer contains the organic compound.

8. The organic light-emitting diode according to claim 7, wherein the first light-emitting material layer comprises a first compound and a second compound, wherein the excited triplet energy level of the first compound is higher than the excited triplet energy level of the second compound, and wherein the first compound comprises the organic compound.

9. The organic light-emitting diode according to claim 8, wherein the first light-emitting material layer further comprises a third compound.

10. The organic light-emitting diode according to claim 9, wherein the excited singlet state energy level of the third compound is lower than that of the excited singlet state energy level of the second compound.

11. The organic light-emitting diode according to claim 8, further comprising 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. The second luminescent material layer contains a fourth compound and a fifth compound.

12. The organic light-emitting diode of claim 11, wherein the fourth compound comprises the organic compound.

13. The organic light-emitting diode according to claim 11, further comprising a third light-emitting material layer disposed opposite to the second light-emitting material layer relative to the first light-emitting material layer. The third luminescent material layer contains a sixth compound and a seventh compound.

14. The organic light-emitting diode of claim 13, wherein at least one of the fourth compound and the sixth compound comprises the organic compound.

15. The organic light-emitting diode according to claim 5, wherein the light-emitting layer comprises a first light-emitting unit disposed between the first electrode and the second electrode, a second light-emitting unit disposed between the first light-emitting unit and the second electrode, and a charge-generating layer disposed between the first light-emitting unit and the second light-emitting unit, and At least one of the first light-emitting unit and the second light-emitting unit contains the organic compound.

16. An organic light-emitting device, comprising: substrate; as well as An organic light-emitting diode according to any one of claims 5 to 15 is disposed above the substrate.

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