Organic light emitting diode and organic light emitting device

Abstract

The present disclosure relates to an organic light emitting diode (OLED) and an organic light emitting device, wherein the organic light emitting diode includes at least one exciton generating layer disposed adjacent to a light emitting material layer that can generate an exciplex. Although the light-emitting region extends to the exciton generation layer and the light-emitting material layer, the exciton recombination region is limited to the light-emitting material layer. The light emitting lifetime of the OLED can be improved by preventing degradation of the material within the light emitting layer. Since holes and electrons can be rapidly injected into the luminescent material layer, the driving voltage of the OLED can be reduced.

Description

[0001] Cross - reference to related applications

[0002] This application claims priority to Korean Patent Application No. 10 - 2023 - 0183106, filed in Korea on December 15, 2023, the entire contents of which are hereby incorporated by reference in their entirety into this application. Technical field

[0003] The present disclosure relates to an organic light - emitting diode (OLED), and more particularly to an OLED having a reduced driving voltage and a beneficial luminous lifetime, and an organic light - emitting device (e.g., a display device or a lighting device) including the OLED. Background art

[0004] As a display device that can replace a liquid - crystal display device (LCD), flat - panel display devices including organic light - emitting diodes (OLEDs) have been studied. The electrode configuration in an OLED can achieve unidirectional or bidirectional images. In addition, an OLED can even be formed on a flexible transparent substrate such as a plastic substrate, so that a flexible or foldable display device can be easily realized using an OLED. In addition, compared with an LCD, an OLED can be driven at a lower voltage and an OLED has favorable high color purity.

[0005] However, there is still a need to develop OLEDs and devices including the OLEDs with improved luminous efficiency and luminous lifetime. Since fluorescent materials utilize only singlet excitons during the light - emitting process, the fluorescent materials of the prior art exhibit low luminous efficiency. At the same time, since phosphorescent materials utilize triplet excitons as well as singlet excitons during the light - emitting process, they can exhibit high luminous efficiency. However, such phosphorescent materials contain metal complexes that may have too short a luminous lifetime for commercial use. Therefore, there is still a need to develop OLEDs with sufficient luminous efficiency and luminous lifetime. Summary of the invention

[0006] Accordingly, some embodiments of the present disclosure relate to an organic light - emitting diode and an organic light - emitting device that substantially eliminate one or more of the problems caused by the limitations and disadvantages of the related art.

[0007] One aspect of the present disclosure provides an organic light - emitting diode and an organic light - emitting device (e.g., a display device or a lighting device) having a reduced driving voltage and a beneficial luminous lifetime.

[0008] Additional features and aspects will be set forth in the following description, and in part will be obvious from the description, or can be learned by practice of the disclosed concepts herein. Other features and aspects of the disclosed concepts can be realized and obtained by the structures particularly pointed out in the written description, or derivable therefrom, and the claims and the drawings.

[0009] To achieve these and other aspects of the inventive concept, as embodied and broadly described, in one aspect, the present disclosure provides an organic light emitting diode, comprising: a first electrode; a second electrode facing the first electrode; and a light emitting layer disposed between the first electrode and the second electrode, wherein the light emitting layer includes a light emitting material layer; and a first exciton generation layer disposed between the first electrode and the light emitting material layer or between the light emitting material layer and the second electrode, wherein the first exciton generation layer includes a first compound and a second compound, wherein the light emitting material layer includes a first host, a second host, and an emitter, wherein the first compound and the first host each independently include an organic compound having a structure of Chemical Formula 1 or Chemical Formula 3, wherein the second compound includes an organic compound having a structure of Chemical Formula 5, and wherein the second host includes an organic compound having a structure of Chemical Formula 7:

[0010] Chemical Formula 1

[0011]

[0012] Chemical Formula 3

[0013]

[0014] Wherein, in Chemical Formulas 1 and 3,

[0015] R 1 to R 5 and R 11 to R 16 are each independently hydrogen, deuterium, a halogen, a cyano group, an unsubstituted or substituted C1 to C 20 alkyl group, an unsubstituted or substituted C2 to C 20 alkenyl group, an unsubstituted or substituted C2 to C 20 alkynyl group, an unsubstituted or substituted C1 to C 20 alkoxy group, an amino group, an unsubstituted or substituted C1 to C 20 alkylamino group, an unsubstituted or substituted C1 to C 20 alkylsilyl group, an unsubstituted or substituted C4 to C 30 cycloalkyl group, an unsubstituted or substituted C3 to C 30 heterocycloalkyl group, an unsubstituted or substituted C6 to C 30Aryl, unsubstituted or substituted C2 to C 30 Heteroaryl, unsubstituted or substituted C7 to C 30 Aralkyl, unsubstituted or substituted C3 to C 30 Heteroaralkyl, unsubstituted or substituted C6 to C 30 Aryloxy, unsubstituted or substituted C2 to C 30 Heteroaryloxy, unsubstituted or substituted C6 to C 30 Arylamino, unsubstituted or substituted C2 to C 30 Heteroarylamino, unsubstituted or substituted C6 to C 30 Arylsilyl, unsubstituted or substituted C2 to C 30 Heteroarylsilyl, unsubstituted or substituted C1 to C 20 Alkylgermyl, unsubstituted or substituted C6 to C 30 Arylgermyl, unsubstituted or substituted C2 to C 30 Heteroarylgermyl, unsubstituted or substituted C6 to C 30 Triarylmethyl, or unsubstituted or substituted C2 to C 30 Triheteroarylmethyl, where when a1 is 2, 3, 4 or 5, each R 1 Are the same as or different from each other, when a2 is 2, 3 or 4, each R 2 Are the same as or different from each other, when a3 is 2, 3 or 4, each R 3 Are the same as or different from each other, when a4 is 2 or 3, each R 4 Are the same as or different from each other, when a5 is 2, 3 or 4, each R 5 Are the same as or different from each other, when b1 is 2, 3 or 4, each R 11 Are the same as or different from each other, when b2 is 2, 3 or 4, each R 12 Are the same as or different from each other, when b3 is 2, 3 or 4, each R 13 Are the same as or different from each other, when b4 is 2, 3 or 4, each R 14 Are the same as or different from each other, when b5 is 2, 3 or 4, each R 15 Are the same as or different from each other, and when b6 is 2, 3 or 4, each R 16 Are the same as or different from each other;

[0016] a1 is 0, 1, 2, 3, 4 or 5;

[0017] a2, a3, a5, b1, b2, b3, b4, b5 and b6 are each independently 0, 1, 2, 3 or 4; and

[0018] a4 is 0, 1, 2 or 3,

[0019] Chemical formula 5

[0020]

[0021] Wherein, in Chemical formula 5,

[0022] Z 1 is C, Si or Ge;

[0023] R 21 to R 28 each independently is hydrogen, deuterium, halogen, cyano, unsubstituted or substituted C1 to C 20 alkyl, unsubstituted or substituted C2 to C 20 alkenyl, unsubstituted or substituted C2 to C 20 alkynyl, unsubstituted or substituted C1 to C 20 alkoxy, amino, unsubstituted or substituted C1 to C 20 alkylamino, unsubstituted or substituted C1 to C 20 alkylsilyl, unsubstituted or substituted C4 to C 30 cycloalkyl, unsubstituted or substituted C3 to C 30 heterocycloalkyl, unsubstituted or substituted C6 to C 30 aryl, unsubstituted or substituted C6 to C 30 heteroaryl, unsubstituted or substituted C7 to C 30 aralkyl, unsubstituted or substituted C3 to C 30 heteroaralkyl, unsubstituted or substituted C6 to C 30 aryloxy, unsubstituted or substituted C2 to C 30 heteroaryloxy, unsubstituted or substituted C6 to C 30 arylamino, unsubstituted or substituted C2 to C 30 heteroarylamino, unsubstituted or substituted C6 to C 30 arylsilyl, unsubstituted or substituted C2 to C 30 heteroarylsilyl, unsubstituted or substituted C1 to C 20 alkylgermyl, unsubstituted or substituted C6 to C 30 arylgermyl, unsubstituted or substituted C2 to C 30 heteroarylgermyl, unsubstituted or substituted C6 to C 30 triarylmethyl, or unsubstituted or substituted C2 to C 30 triheteroarylmethyl, wherein when c1 is 2, 3 or 4, each R 21 is the same as or different from each other, when c2 is 2, 3 or 4, each R 22identical to or different from each other, and when c3 is 2, 3 or 4, each R 23 identical to or different from each other, and when c4 is 2, 3 or 4, each R 24 identical to or different from each other, and when c5 is 2, 3 or 4, each R 25 identical to or different from each other, and when c6 is 2, 3, 4 or 5, each R 26 identical to or different from each other, and when c7 is 2, 3, 4 or 5, each R 27 identical to or different from each other, and when c8 is 2, 3, 4 or 5, each R 28 identical to or different from each other;

[0024] c1, c2, c3, c4 and c5 are each independently 0, 1, 2, 3 or 4; and

[0025] c6, c7 and c8 are each independently 0, 1, 2, 3, 4 or 5,

[0026] Chemical formula 7

[0027]

[0028] wherein, in Chemical formula 7,

[0029] R 31 to R 33 are each independently hydrogen, deuterium, halogen, cyano, unsubstituted or substituted C1 to C 20 alkyl, unsubstituted or substituted C2 to C 20 alkenyl, unsubstituted or substituted C2 to C 20 alkynyl, unsubstituted or substituted C1 to C 20 alkoxy, amino, unsubstituted or substituted C1 to C 20 alkylamino, unsubstituted or substituted C1 to C 20 alkylsilyl, unsubstituted or substituted C4 to C 30 cycloalkyl, unsubstituted or substituted C3 to C 30 heterocycloalkyl, unsubstituted or substituted C6 to C 30 aryl, unsubstituted or substituted C2 to C 30 heteroaryl, unsubstituted or substituted C7 to C 30 aralkyl, unsubstituted or substituted C3 to C 30 heteroaralkyl, unsubstituted or substituted C6 to C 30 aryloxy, unsubstituted or substituted C2 to C 30 heteroaryloxy, unsubstituted or substituted C6 to C 30 arylamino, unsubstituted or substituted C2 to C 30Heteroarylamino, unsubstituted or substituted C6 to C 30 Arylsilyl, unsubstituted or substituted C2 to C 30 Heteroarylsilyl, unsubstituted or substituted C1 to C 20 Alkylgermyl, unsubstituted or substituted C6 to C 30 Arylgermyl, unsubstituted or substituted C2 to C 30 Heteroarylgermyl, unsubstituted or substituted C6 to C 30 Triarylmethyl, unsubstituted or substituted C2 to C 30 Triheteroarylmethyl, or has a structure of Formula 8 below, wherein when d1 is 2, 3 or 4, each R 31 is the same as or different from each other, and when d2 is 2, 3 or 4, each R 32 is the same as or different from each other, d1 and d2 are each independently 0, 1, 2, 3 or 4, wherein the polycycle containing boron and oxygen has at least one heteroaryl having a structure of Formula 9 below:

[0030] Formula 8

[0031]

[0032] wherein, in Formula 8,

[0033] Z 2 is C, Si or Ge;

[0034] R 34 to R 36 are each independently unsubstituted or substituted C6 to C 30 aryl, unsubstituted or substituted C2 to C 30 heteroaryl, unsubstituted or substituted C7 to C 30 aralkyl, unsubstituted or substituted C3 to C 30 heteroaralkyl, unsubstituted or substituted C6 to C 30 aryloxy, or unsubstituted or substituted C2 to C 30 heteroaryloxy;

[0035] L 1 is a direct bond, unsubstituted or substituted C6 to C 30 arylene or unsubstituted or substituted C2 to C 30 heteroarylene; and

[0036] The wavy line indicates the connecting position,

[0037] Formula 9

[0038]

[0039] Among them, in Chemical Formula 9,

[0040] R 41 and R 42 are each independently hydrogen, deuterium, a halogen, a cyano group, an unsubstituted or substituted C1 to C 20 alkyl group, an unsubstituted or substituted C2 to C 20 alkenyl group, an unsubstituted or substituted C2 to C 20 alkynyl group, an unsubstituted or substituted C1 to C 20 alkoxy group, an amino group, an unsubstituted or substituted C1 to C 20 alkylamino group, an unsubstituted or substituted C1 to C 20 alkylsilyl group, an unsubstituted or substituted C4 to C 30 cycloalkyl group, an unsubstituted or substituted C3 to C 30 heterocycloalkyl group, an unsubstituted or substituted C6 to C 30 aryl group, an unsubstituted or substituted C2 to C 30 heteroaryl group, an unsubstituted or substituted C7 to C 30 aralkyl group, an unsubstituted or substituted C3 to C 30 heteroaralkyl group, an unsubstituted or substituted C6 to C 30 aryloxy group, an unsubstituted or substituted C2 to C 30 heteroaryloxy group, an unsubstituted or substituted C6 to C 30 arylamino group, an unsubstituted or substituted C2 to C 30 heteroarylamino group, an unsubstituted or substituted C6 to C 30 arylsilyl group, an unsubstituted or substituted C2 to C 30 heteroarylsilyl group, an unsubstituted or substituted C1 to C 20 alkylgermyl group, an unsubstituted or substituted C6 to C 30 arylgermyl group, an unsubstituted or substituted C2 to C 30 heteroarylgermyl group, an unsubstituted or substituted C6 to C 30 triarylmethyl group, or an unsubstituted or substituted C2 to C 30 triheteroarylmethyl group, where when e1 is 2, 3 or 4, each R 41 is the same as or different from each other, and when e2 is 2, 3 or 4, each R 42 is the same as or different from each other, e1 and e2 are each independently 0, 1, 2, 3 or 4, or

[0041] Optionally,

[0042] two adjacent Rs 41 and / or two adjacent Rs42 Further joined together to form an unsubstituted or substituted C4 to C 20 alicyclic ring, an unsubstituted or substituted C3 to C 20 heteroalicyclic ring, an unsubstituted or substituted C6 to C 20 aromatic ring, or an unsubstituted or substituted C2 to C 20 heteroaromatic ring; and

[0043] The wavy line indicates the connection position.

[0044] In another embodiment, the light-emitting layer may further include a second exciton generation layer disposed opposite to the first exciton generation layer with respect to the light-emitting material layer.

[0045] As an example, the second exciton generation layer may contain a third compound and a fourth compound. The third compound may include an organic compound having a structure of Chemical Formula 1 or Chemical Formula 3, and the fourth compound may include an organic compound having a structure of Chemical Formula 5.

[0046] In one embodiment, the difference or energy band gap between the highest occupied molecular orbital (HOMO) energy level of the first compound and the HOMO energy level of the second compound may be about 0.2 eV or greater and about 0.8 eV or less.

[0047] In another embodiment, the difference or energy band gap between the highest HOMO energy level among the HOMO energy levels of the first host and the second host and the HOMO energy level of the first compound may be about 0.3 eV or less.

[0048] In another embodiment, the difference or energy band gap between the lowest unoccupied molecular orbital (LUMO) energy level of the first compound and the LUMO energy level of the second compound may be about 0.2 eV or greater and about 0.8 eV or less.

[0049] In another embodiment, the difference or energy band gap between the lowest LUMO energy level among the LUMO energy levels of the first host and the second host and the LUMO energy level of the second compound may be about 0.3 eV or less.

[0050] In another embodiment, the lowest excited triplet energy level of the first compound may be higher than the lowest excited triplet energy level of the second compound, and the lowest excited triplet energy level of the second compound may be higher than the lowest excited triplet energy level of the second host.

[0051] For example, the luminescent substance may include an organometallic compound having a structure of the following Chemical Formula 11:

[0052] Chemical Formula 11

[0053]

[0054] Among them, in Chemical Formula 11,

[0055] R 51 to R 56 are each independently hydrogen, deuterium, halogen, cyano, unsubstituted or substituted C1 to C 20 alkyl, unsubstituted or substituted C2 to C 20 alkenyl, unsubstituted or substituted C2 to C 20 alkynyl, unsubstituted or substituted C1 to C 20 alkoxy, amino, unsubstituted or substituted C1 to C 20 alkylamino, unsubstituted or substituted C1 to C 20 alkylsilyl, unsubstituted or substituted C4 to C 30 cycloalkyl, unsubstituted or substituted C3 to C 30 heterocycloalkyl, unsubstituted or substituted C6 to C 30 aryl, unsubstituted or substituted C2 to C 30 heteroaryl, unsubstituted or substituted C7 to C 30 aralkyl, unsubstituted or substituted C3 to C 30 heteroaralkyl, unsubstituted or substituted C6 to C 30 aryloxy, unsubstituted or substituted C2 to C 30 heteroaryloxy, unsubstituted or substituted C6 to C 30 arylamino, unsubstituted or substituted C2 to C 30 heteroarylamino, unsubstituted or substituted C6 to C 30 arylsilyl, unsubstituted or substituted C2 to C 30 heteroarylsilyl, unsubstituted or substituted C1 to C 20 alkylgermyl, unsubstituted or substituted C6 to C 30 arylgermyl, unsubstituted or substituted C2 to C 30 heteroarylgermyl, unsubstituted or substituted C6 to C 30 triarylmethyl, or unsubstituted or substituted C2 to C 30 triheteroarylmethyl, where when f1 is 2, 3 or 4, each R 51 is the same as or different from each other, when f2 is 2, 3 or 4, each R 52 is the same as or different from each other, when f3 is 2, each R 53 is the same as or different from each other, when f4 is 2 or 3, each R 54each being the same as or different from one another, and when f5 is 2, 3 or 4, each R 55 each being the same as or different from one another;

[0056] f1, f2 and f5 are each independently 0, 1, 2, 3 or 4;

[0057] f3 is 0, 1 or 2; and

[0058] f4 is 0, 1, 2 or 3.

[0059] In one embodiment, the first compound and the second compound in the first exciton generation layer may be mixed at a weight ratio of about 4:1 to about 1:4.

[0060] The light-emitting layer may include a single light-emitting part or include a plurality of light-emitting parts to form a tandem structure.

[0061] For example, the light-emitting layer may include: a first light-emitting part disposed between the first electrode and the second electrode and including a first light-emitting material layer; a second light-emitting part disposed between the first light-emitting part and the second electrode and including a second light-emitting material layer; and a first charge generation layer disposed between the first light-emitting part and the second light-emitting part, and at least one of the first light-emitting material layer and the second light-emitting material layer may include a first host, a second host, and a light-emitting body.

[0062] As an example, the first light-emitting material layer may include a first host, a second host, and a light-emitting body, and the first exciton generation layer may be disposed between the first electrode and the first light-emitting material layer or between the first light-emitting material layer and the first charge generation layer.

[0063] The first light-emitting part may further include a second exciton generation layer disposed opposite to the first exciton generation layer with respect to the first light-emitting material layer.

[0064] In another embodiment, the light-emitting layer may further include: a third light-emitting part disposed between the second light-emitting part and the second electrode and including a third light-emitting material layer; and a second charge generation layer disposed between the second light-emitting part and the third light-emitting part.

[0065] In yet another aspect, the present disclosure provides an organic light-emitting device including a substrate and an organic light-emitting diode above the substrate, such as an organic light-emitting display device or an organic light-emitting lighting device.

[0066] In one or more embodiments, the organic light-emitting diode (OLED) and the organic light-emitting device include at least one exciton generation layer disposed adjacent to the light-emitting material layer and including a first compound and a second compound capable of generating an exciplex.

[0067] The exciton recombination region or area in the OLED can extend to the exciton generation layer adjacent to the light-emitting material layer. Due to the extension of the exciton recombination region, the concentration or level of excitons in the light-emitting material layer is reduced. Deterioration of the light-emitting material, charge transport material, and charge blocking material caused by non-radiative quenching excitons can be prevented. Since the reduction in the luminescence lifetime due to material deterioration is suppressed, the luminescence lifetime of the OLED can be improved.

[0068] The light-emitting region or area is limited to the light-emitting material layer with beneficial out-coupling efficiency. Due to the increased out-coupling efficiency, the external quantum efficiency of the OLED can be improved. In addition, since the amount of the light emitter can be reduced, the material cost can be lowered.

[0069] The light-emitting material layer contains a host with delayed fluorescence characteristics. Since the difference between the singlet excited state energy level and the triplet excited state energy level of the host with delayed fluorescence characteristics is very small, the energy of exciton recombination in the host can be reduced. In addition, since exciplexes with delayed fluorescence characteristics can be generated in the exciton generation layer, the energy of exciton recombination in the exciton generation layer can be reduced. Since the difference or bandgap between the exciplex with delayed fluorescence characteristics and the host can be reduced, the voltage for injecting charges into the light-emitting material layer can be lowered.

[0070] An OLED with a reduced driving voltage and beneficial luminescence lifetime can be achieved by: applying a light-emitting material layer containing a host with delayed fluorescence characteristics and at least one exciton generation layer that can generate exciplexes and is disposed adjacent to the light-emitting material layer. An environmentally friendly OLED and an organic light-emitting device with reduced power consumption and capable of implementing the ESG (Environmental, Social, and Governance) concept can be manufactured.

[0071] It should be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the claimed inventive concept. Brief Description of the Drawings

[0072] The drawings included to provide a further understanding of the present disclosure are incorporated in and constitute a part of this application, illustrate embodiments of the present disclosure, and together with the description are used to explain the principles of the present disclosure.

[0073] Figure 1 A schematic circuit diagram of an organic light-emitting display device according to one or more embodiments of the present disclosure is shown.

[0074] Figure 2 A cross-sectional view of an organic light-emitting display device as an example of an organic light-emitting device according to an embodiment of the present disclosure is shown.

[0075] Figure 3 Shows a cross-sectional view of an organic light-emitting diode having a single light-emitting part according to an embodiment of the present disclosure.

[0076] Figure 4 Shows a cross-sectional view of an organic light-emitting diode having a single light-emitting part according to another embodiment of the present disclosure.

[0077] Figure 5 Shows a cross-sectional view of an organic light-emitting diode having a single light-emitting part according to another embodiment of the present disclosure.

[0078] Figure 6 Is a schematic diagram of a light-emitting mechanism in the case where an exciton generation layer is formed adjacent to a light-emitting material layer according to an embodiment of the present disclosure.

[0079] Figure 7 Is a schematic diagram of the HOMO energy levels and LUMO energy levels of a first compound and a second compound in an exciton generation layer and a first host and a second host in a light-emitting material layer.

[0080] Figure 8 Is a schematic diagram of charge injection into a light-emitting material layer in the case where an exciplex is generated in an exciton generation layer according to an embodiment of the present disclosure.

[0081] Figure 9 Is a schematic diagram of ineffective charge injection into a light-emitting material layer due to a barrier voltage in the case where an organic layer disposed adjacent to the light-emitting material layer cannot generate an exciplex.

[0082] Figure 10 Is a schematic diagram of a light-emitting region and a recombination region in the case where an exciton generation layer is not formed adjacent to the light-emitting material layer.

[0083] Figure 11 Is a schematic diagram of a light-emitting region and a recombination region in the case where an exciton generation layer is formed adjacent to the light-emitting material layer according to an embodiment of the present disclosure.

[0084] Figure 12 Shows a cross-sectional view of an organic light-emitting display device according to another embodiment of the present disclosure.

[0085] Figure 13 Shows a cross-sectional view of an organic light-emitting diode having a tandem structure with two light-emitting parts according to another embodiment of the present disclosure.

[0086] Figure 14 Shows a cross-sectional view of an organic light-emitting diode having a tandem structure with three light-emitting parts according to another embodiment of the present disclosure.

[0087] Figures 15 to 17 Each is a graph showing the absorption spectrum and photoluminescence spectrum of the materials used in the examples and comparative examples. "Abs" represents the absorption spectrum, and "PL" represents the photoluminescence spectrum. Detailed Description

[0088] Aspects of the present disclosure will now be described in detail with reference to its examples shown in the drawings. Wherever possible, the same reference numerals will be used throughout the drawings to refer to the same or like parts.

[0089] All components of each organic light-emitting display device according to all embodiments of the present disclosure are operatively coupled and configured.

[0090] The light-emitting layer of the organic light-emitting diode includes at least one exciton generation layer having a material capable of generating an exciplex adjacent to a light-emitting material layer having a host with delayed fluorescence characteristics. By applying a light-emitting layer including a light-emitting material layer and an exciton generation layer, the driving voltage of the organic light-emitting diode can be reduced, and the light-emitting lifetime of the organic light-emitting diode can be improved. As an example, a light-emitting layer including a light-emitting material layer and an exciton generation layer can be applied to an organic light-emitting diode having a single light-emitting portion in a red pixel region, a green pixel region, and / or a blue pixel region. Alternatively, a light-emitting layer including a light-emitting material layer and an exciton generation layer can be applied to an organic light-emitting diode having a tandem structure in which at least two light-emitting portions are stacked.

[0091] As an example, in one or more embodiments of the present disclosure, an organic light-emitting diode can be applied to an organic light-emitting device, such as an organic light-emitting display device or an organic light-emitting lighting device. As an example, an organic light-emitting display device will be described.

[0092] Figure 1 A schematic circuit diagram of an organic light-emitting display device according to one or more embodiments of the present disclosure is shown. As Figure 1 shown, gate lines GL, data lines DL, and power lines PL that cross each other are provided in the organic light-emitting display device to define a pixel region P. A switching thin-film transistor Ts, a driving thin-film transistor Td, a storage capacitor Cst, and an organic light-emitting diode D are provided within the pixel region P. The pixel region P may include a first pixel region, a second pixel region, and a third pixel region. However, embodiments of the present disclosure are not limited to such examples. The organic light-emitting display device may include a plurality of such pixel regions P that can be arranged in a matrix configuration or other configuration.

[0093] The switching thin film transistor Ts is connected to the gate line GL and the data line DL. The driving thin film transistor Td and the storage capacitor Cst are connected between the switching thin film transistor Ts and the power line PL. The organic light emitting diode D is connected to the driving thin film transistor Td. When the switching thin film transistor Ts is turned on by a gate signal applied to the gate line GL, the data signal applied to the data line DL is applied to the gate electrode of the driving thin film transistor Td and one electrode of the storage capacitor Cst through the switching thin film transistor Ts.

[0094] The driving thin film transistor Td is turned on by the data signal applied to the gate electrode 130( Figure 2 ), so that a current proportional to the data signal is supplied from the power line PL to the organic light emitting diode D through the driving thin film transistor Td. Then, the organic light emitting diode D emits light having a brightness proportional to the current flowing through the driving thin film transistor Td. In this case, the storage capacitor Cst is charged with a voltage proportional to the data signal, so that the voltage of the gate electrode in the driving thin film transistor Td remains constant during one frame. Therefore, the organic light emitting display device can display a desired image.

[0095] Figure 2 A schematic cross-sectional view of an organic light emitting display device according to an embodiment of the present disclosure is shown. It can be used in the display device of Figure 2 this application or other figures Figure 1 with the pixel circuit configuration.

[0096] As Figure 2 shown, the organic light emitting display device 100 includes a substrate 102, a thin film transistor Tr on the substrate 102, and an organic light emitting diode D connected to the thin film transistor Tr.

[0097] As an example, the substrate 102 may include a red pixel region, a green pixel region, and a blue pixel region, and the organic light emitting diode D may be located in each pixel region. The organic light emitting diodes D that emit red, green, and blue light respectively are located in the red pixel region, the green pixel region, and the blue pixel region respectively.

[0098] The substrate 102 may include, but is not limited to, glass, thin flexible materials, and / or polymer plastics. For example, the flexible material may be selected from, but not limited to, polyimide (PI), polyethersulfone (PES), polyethylene naphthalate (PEN), polyethylene terephthalate (PET), polycarbonate (PC), and / or combinations thereof. The substrate 102 on which the thin film transistor Tr and the organic light emitting diode D are arranged forms an array substrate.

[0099] A buffer layer 106 can be provided on the substrate 102. The thin-film transistor Tr can be provided on the buffer layer 106. In some embodiments, the buffer layer 106 can be omitted.

[0100] A semiconductor layer 110 is provided on the buffer layer 106. In one embodiment, the semiconductor layer 110 can include, but is not limited to, an oxide semiconductor material. In this case, a light-shielding pattern can be provided below the semiconductor layer 110, and the light-shielding pattern can prevent light from incident on the semiconductor layer 110, thereby preventing or reducing the degradation of the semiconductor layer 110 by light. Alternatively, the semiconductor layer 110 can include polysilicon. In this case, opposite edges of the semiconductor layer 110 can be doped with impurities.

[0101] A gate insulating layer 120 including an insulating material is provided on the semiconductor layer 110. The gate insulating layer 120 can include, but is not limited to, an inorganic insulating material such as silicon oxide (SiO x , where 0 < x ≤ 2) or silicon nitride (SiN x , where 0 < x ≤ 2).

[0102] A gate electrode 130 made of a conductive material such as metal is provided on the gate insulating layer 120 corresponding to the center of the semiconductor layer 110. When, as Figure 2 shown, the gate insulating layer 120 is provided over the entire area of the substrate 102, the gate insulating layer 120 can be patterned in the same manner as the gate electrode 130.

[0103] An interlayer insulating layer 140 including an insulating material is provided on the gate electrode 130 and covers the entire surface of the substrate 102. The interlayer insulating layer 140 can include, but is not limited to, an inorganic insulating material such as silicon oxide (SiO x , where 0 < x ≤ 2) or silicon nitride (SiN x , where 0 < x ≤ 2), or an organic insulating material such as benzocyclobutene or photo-acryl.

[0104] The interlayer insulating layer 140 has a first semiconductor layer contact hole 142 and a second semiconductor layer contact hole 144 that expose or do not cover a portion of the surface of the semiconductor layer 110 that is closer to the opposite end than the center. The first semiconductor layer contact hole 142 and the second semiconductor layer contact hole 144 are provided on opposite sides of the gate electrode 130 and are spaced apart from the gate electrode 130. In Figure 2In [the structure], the first semiconductor layer contact hole 142 and the second semiconductor layer contact hole 144 are formed in the gate insulating layer 120 and the interlayer insulating layer 140. Alternatively, in some embodiments, when the gate insulating layer 120 is patterned in the same manner as the gate electrode 130, the first semiconductor layer contact hole 142 and the second semiconductor layer contact hole 144 may be formed only in the interlayer insulating layer 140.

[0105] A source electrode 152 and a drain electrode 154 made of a conductive material such as metal are provided on the interlayer insulating layer 140. The source electrode 152 and the drain electrode 154 are spaced apart from each other on opposite sides of the gate electrode 130, and contact both sides of the semiconductor layer 110 through the first semiconductor layer contact hole 142 and the second semiconductor layer contact hole 144, respectively.

[0106] The semiconductor layer 110, the gate electrode 130, the source electrode 152, and the drain electrode 154 constitute a thin film transistor Tr serving as a driving element. Figure 2 The thin film transistor Tr in [the structure] has a coplanar structure in which the gate electrode 130, the source electrode 152, and the drain electrode 154 are provided on the semiconductor layer 110. Alternatively, the thin film transistor Tr may have an inverted staggered structure in which the gate electrode is provided below the semiconductor layer and the source electrode and the drain electrode are provided on the semiconductor layer. In this case, the semiconductor layer may include amorphous silicon.

[0107] A gate line GL and a data line DL that cross each other to define the pixel region P, and a switching element Ts connected to the gate line GL and the data line DL may also be formed in the pixel region P. The switching element Ts is connected to the thin film transistor Tr serving as a driving element. In addition, a power line PL is spaced apart in parallel from the gate line GL or the data line DL. The thin film transistor Tr may also include a storage capacitor Cst configured to keep the voltage of the gate electrode 130 constant for one frame.

[0108] A passivation layer 160 is provided on the source electrode 152 and the drain electrode 154. On the entire substrate 102, the passivation layer 160 covers the thin film transistor Tr. The passivation layer 160 has a flat top surface and a drain contact hole (or contact hole) 162 that exposes the drain electrode 154 of the thin film transistor Tr or does not cover the drain electrode 154 of the thin film transistor Tr. Although the drain contact hole 162 is provided on the second semiconductor layer contact hole 144, it may be spaced apart from the second semiconductor layer contact hole 144.

[0109] The organic light emitting diode D (OLED D) includes a first electrode 210 provided on the passivation layer 160 and connected to the drain electrode 154 of the thin film transistor Tr. The OLED D also includes a light emitting layer 230 and a second electrode 220 that are sequentially provided on the first electrode 210, respectively.

[0110] One of the first electrode 210 and the second electrode 220 can be an anode, and the other of the first electrode 210 and the second electrode 220 can be a cathode. One of the first electrode 210 and the second electrode 220 can be a reflective electrode, and the other of the first electrode 210 and the second electrode 220 can be a transmissive electrode.

[0111] The first electrode 210 is separately disposed in each pixel region P. In one embodiment, the first electrode 210 can be an anode and include a conductive material having a relatively high work function value. For example, the first electrode 210 can include a transparent conductive oxide (TCO).

[0112] In one embodiment, when the organic light emitting display device 100 is a bottom emission type, the first electrode 210 can have a single-layer structure of TCO. Alternatively, when the organic light emitting display device 100 is a top emission type, a reflective electrode or a reflective layer can be disposed under the first electrode 210. For example, the reflective electrode or the reflective layer can include, but is not limited to, silver (Ag) or an aluminum-palladium-copper (APC) alloy. As an example, in the top emission type OLED D, the first electrode 210 can have a three-layer structure of, but not limited to, ITO / Ag / ITO or ITO / APC / ITO.

[0113] In addition, a bank layer 164 is disposed on the passivation layer 160 to cover the edge of the first electrode 210. The bank layer 164 exposes the center of the first electrode 210 corresponding to each pixel region or does not cover the center of the first electrode 210 corresponding to each pixel region. In some embodiments, the bank layer 164 can be omitted.

[0114] A light emitting layer 230 is disposed on the first electrode 210. In one embodiment, the light emitting layer 230 can include a light emitting material layer (EML) and at least one exciton generation layer (EGL). Alternatively, the light emitting layer 230 can have a multi-layer structure of a hole injection layer (HIL), a hole transport layer (HTL), an electron blocking layer (EBL), an EML, a hole blocking layer (HBL), an electron transport layer (ETL), an electron injection layer (EIL), an EGL, and / or a charge generation layer (CGL).

[0115] In one embodiment, the light emitting layer 230 can have a single light emitting portion ( Figures 3 to 5 ). Alternatively, the light emitting layer 230 can have a plurality of light emitting portions to form a tandem structure. For example, the light emitting layer 230 can be applied to an OLED having a single light emitting portion in each of the red pixel region, the green pixel region, and the blue pixel region. Alternatively, the light emitting layer 230 can be applied to a tandem type OLED in which at least two light emitting portions are stacked.

[0116] The light-emitting layer 230 may include an EML having a host with delayed fluorescence characteristics and at least one EGL disposed adjacent to the EML that can generate an exciplex, such that the driving voltage of the OLED can be reduced and the luminous lifetime of the OLED D can be improved.

[0117] A second electrode 220 is disposed on the substrate 102 on which the light-emitting layer 230 is disposed. The second electrode 220 may be disposed over the entire display area. The second electrode 220 may include a conductive material having a relatively low work function value compared to the first electrode 210. The second electrode 220 may be a cathode that provides electrons. When the organic light-emitting display device 100 is a top-emitting type, the second electrode 220 is thin to have a light-transmitting (semi-transmissive) characteristic.

[0118] In addition, a encapsulation film 170 may be disposed on the second electrode 220 to prevent or reduce external moisture from infiltrating into the OLED D. The encapsulation film 170 may have a laminated structure including, but not limited to, a first inorganic insulating film 172, an organic insulating film 174, and a second inorganic insulating film 176. In certain embodiments, the encapsulation film 170 may be omitted.

[0119] A polarizing plate may be attached to the encapsulation film 170 to reduce reflection of external light. For example, the polarizing plate may be a circular polarizing plate. When the organic light-emitting display device 100 is a bottom-emitting type, the polarizing plate may be disposed under the substrate 102. Alternatively, when the organic light-emitting display device 100 is a top-emitting type, the polarizing plate may be disposed on the encapsulation film 170. In addition, a cover window may be attached to the encapsulation film 170 or the polarizing plate. In this case, the substrate 102 and the cover window may have flexible characteristics, and thus the organic light-emitting display device 100 may be a flexible display device.

[0120] The OLED D is described in more detail. Figure 3 A schematic cross-sectional view of an organic light-emitting diode having a single light-emitting portion according to an embodiment of the present disclosure is shown. For example, Figure 3 is shown Figure 1 and Figure 2 an example (OLED D1) of the OLED D in

[0121] As Figure 3 shown, an OLED D1 according to an example of the present disclosure includes a first electrode 210 and a second electrode 220 facing each other and a light-emitting layer 230 disposed between the first electrode 210 and the second electrode 220. The organic light-emitting display device 100 includes a red pixel region, a green pixel region, and a blue pixel region, and the OLED D1 may be disposed in the red pixel region, the green pixel region, and / or the blue pixel region. As an example, the OLED D1 may be disposed in the blue pixel region.

[0122] In one embodiment, the light-emitting layer 230 includes a light-emitting material layer (EML) 340 disposed between the first electrode 210 and the second electrode 220, and an exciton generation layer (EGL) disposed between the first electrode 210 and the EML 340, such as between a hole transport layer (HTL) 320 or an electron blocking layer (EBL) 330 and the EML 340. The light-emitting layer 230 may include at least one of the HTL 320 disposed between the first electrode 210 and the EML 340 and an electron transport layer (ETL) 370 disposed between the second electrode 220 and the EML 340. In certain embodiments, the light-emitting layer 230 may further include at least one of a hole injection layer (HIL) 310 disposed between the first electrode 210 and the HTL 320 and an electron injection layer (EIL) 380 disposed between the second electrode 220 and the ETL 370. Alternatively or additionally, the light-emitting layer 230 may further include a first exciton blocking layer, i.e., the EBL 330, disposed between the HTL 320 and the EML 340, such as between the HTL 320 and the EGL 350, and / or a second exciton blocking layer, i.e., a hole blocking layer (HBL) 360, disposed between the EML 340 and the ETL 370.

[0123] The first electrode 210 may be an anode that provides holes to the EML 340. The first electrode 210 may include a conductive material having a relatively high work function value, such as a transparent conductive oxide (TCO). As an example, the first electrode 210 may include, but is not limited to, 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.

[0124] The second electrode 220 may be a cathode that provides electrons to the EML 340. The second electrode 220 may include a conductive material having a relatively low work function value, i.e., a high-reflection material. As an example, the second electrode 220 may include, but is not limited to, aluminum (Al), magnesium (Mg), calcium (Ca), silver (Ag), their alloys, and / or their combinations, such as an aluminum-magnesium alloy (Al-Mg).

[0125] The EGL 350 includes a first compound 352 and a second compound 354 that are recombined to generate excitons. The first compound 352 may be a P-type (or hole-type) compound having relatively beneficial hole affinity characteristics and / or hole transport characteristics. The second compound 354 may be an N-type (or electron-type) compound having relatively beneficial electron affinity characteristics and / or electron transport characteristics.

[0126] The first compound 352 may be a carbazole-containing organic compound. The first compound 352 includes an organic compound having a structure of Formula 1 or Formula 3 below:

[0127] Formula 1

[0128]

[0129] Formula 3

[0130]

[0131] Wherein, in Formulas 1 and 3,

[0132] R 1 to R 5 and R 11 to R 16 are each independently hydrogen, deuterium, halogen, cyano, unsubstituted or substituted C1 to C 20 alkyl, unsubstituted or substituted C2 to C 20 alkenyl, unsubstituted or substituted C2 to C 20 alkynyl, unsubstituted or substituted C1 to C 20 alkoxy, amino, unsubstituted or substituted C1 to C 20 alkylamino, unsubstituted or substituted C1 to C 20 alkylsilyl, unsubstituted or substituted C4 to C 30 cycloalkyl, unsubstituted or substituted C3 to C 30 heterocycloalkyl, unsubstituted or substituted C6 to C 30 aryl, unsubstituted or substituted C6 to C 30 heteroaryl, unsubstituted or substituted C2 to C 30 aryalkyl, unsubstituted or substituted C3 to C 30 heteroaryalkyl, unsubstituted or substituted C6 to C 30 aryloxy, unsubstituted or substituted C2 to C 30 heteroaryloxy, unsubstituted or substituted C6 to C 30 arylamino, unsubstituted or substituted C2 to C 30 heteroarylamino, unsubstituted or substituted C6 to C 30 arylsilyl, unsubstituted or substituted C2 to C 30 heteroarylsilyl, unsubstituted or substituted C1 to C 20 alkylgermyl, unsubstituted or substituted C6 to C 30 arylgermyl, unsubstituted or substituted C2 to C 30 heteroarylgermyl, unsubstituted or substituted C6 to C30 triarylmethyl, or unsubstituted or substituted C2 to C 30 triheteroarylmethyl, wherein when a1 is 2, 3, 4 or 5, each R 1 The same or different from each other, when a2 is 2, 3 or 4, each R 2 The same or different from each other, when a3 is 2, 3 or 4, each R 3 The same or different from each other, when a4 is 2 or 3, each R 4 The same or different from each other, when a5 is 2, 3 or 4, each R 5 The same or different from each other, when b1 is 2, 3 or 4, each R 11 The same or different from each other, when b2 is 2, 3 or 4, each R 12 The same or different from each other, when b3 is 2, 3 or 4, each R 13 The same or different from each other, when b4 is 2, 3 or 4, each R 14 The same or different from each other, when b5 is 2, 3 or 4, each R 15 are the same as or different from each other, and when b6 is 2, 3 or 4, each R 16 the same as or different from one another;

[0133] a1 is 0, 1, 2, 3, 4 or 5;

[0134] a2, a3, a5, b1, b2, b3, b4, b5 and b6 are each independently 0, 1, 2, 3 or 4; and

[0135] a4 is 0, 1, 2 or 3.

[0136] As used herein, the term "unsubstituted" means that hydrogen is directly attached to the carbon atom. As used herein, "hydrogen" may refer to protium.

[0137] As used herein, "substituted" means that a hydrogen is replaced by a substituent. The substituent may include, but is not limited to, deuterium, unsubstituted or substituted C1 to C 20 Alkyl, unsubstituted or substituted C1 to C 20 Alkoxy, halogen, cyano, hydroxy, carboxyl, carbonyl, amino, C1 to C 10 Alkylamino, C6 to C 30 Arylamino, C2 to C 30 heteroarylamino, nitro, hydrazide, sulfonic acid, unsubstituted or substituted C1 to C 10 Alkylsilyl, unsubstituted or substituted C1 to C 10 Alkoxysilyl, unsubstituted or substituted C3 to C 20 Cycloalkylsilyl, unsubstituted or substituted C6 to C 30Arylsilyl, unsubstituted or substituted C2 to C 30 Heteroarylsilyl, unsubstituted or substituted C6 to C 30 Aryl, unsubstituted or substituted C2 to C 30 Heteroaryl, or any combination of these groups.

[0138] As used herein, the term "hetero" in terms such as "heteroalicyclic ring", "heterocycloalkyl", "heteroaryl", "heteroaralkyl", "heteroaryloxy", "heteroarylamino", "heteroarylsilyl", "heteroarylgermyl", "heteroarylene", etc. means that at least one carbon atom (e.g., 1 to 5 carbon atoms) constituting an aliphatic chain, an alicyclic group or an alicyclic ring, or an aromatic group or an aromatic ring is replaced by at least one heteroatom selected from N, O, S, and P.

[0139] For example, C6 to C 30 Aryl, C2 to C 30 Heteroaryl, C6 to C 30 Arylamino, C2 to C 30 Heteroarylamino, C6 to C 30 Substituents of aromatic rings and C3 to C 30 Heteroaromatic rings may include C1 to C 20 Alkyl, C6 to C 30 Aryl, C2 to C 30 Heteroaryl, C6 to C 30 Arylamino and C2 to C 30 At least one of heteroarylamino.

[0140] As used herein, C6 to C 30 Aryl may include, but is not limited to, non-fused or fused aryls, such as phenyl, biphenyl, terphenyl, naphthyl, anthryl, pentacenyl, indenyl, indacenyl, heptacenyl, biphenylene, indacenyl, phenalenyl, phenanthryl, benzophenanthryl, dibenzophenanthryl, azulenyl, pyrenyl, fluoranthenyl, triphenylene, yl, tetraphenylene, quaterphenyl, pleiadenyl, picenyl, pentaphenylene, quinquephenyl, fluorenyl, indeno[1,2-b]fluorene, or spirofluorene.

[0141] As used herein, C2 to C 30Heteroaryl may include, but is not limited to, non-fused or fused heteroaryl, such as pyrrolyl, pyridyl, pyrimidinyl, pyrazinyl, pyridazinyl, triazinyl, tetrazinyl, imidazolyl, pyrazolyl, indolyl, isoindolyl, indazolyl, indolizinyl, pyrrolizinyl, carbazolyl, benzocarbazolyl, dibenzocarbazolyl, indolocarbazolyl, indeno carbazolyl, benzofurocarbazolyl, benzothienocarbazolyl, carbolinyl, quinolinyl, isoquinolinyl, phthalazinyl, quinoxalinyl, cinnolinyl, quinazolinyl, quinazolinyl, purinyl, benzoquinolinyl, benzoisoquinolinyl, benzquinazolinyl, benzquinoxalinyl, acridinyl, phenazinyl, phenoxazinyl, phenothiazinyl, phenanthrolinyl, azetidinyl, phenanthridinyl, pteridinyl, naphthyridinyl, furyl, pyranyl, phenoxazinyl, oxazolyl, dioxazolyl, triazolyl, dibenzofuranyl, benzofuranyl, dibenzofuranyl, thiopyranyl, xanthenyl, chromenyl, isochromenyl, thiazinyl, thienyl, benzothienyl, dibenzothienyl, difuro[3,2-b:2',3'-d]pyridinyl, benzofuro[3,2-b:2',3'-d]dibenzofuranyl, benzothieno[3,2-b:2',3'-d]benzothienyl, benzothieno[3,2-b:2',3'-d]dibenzothienyl, benzothieno[3,2-b:2',3'-d]benzofuranyl, benzothieno[3,2-b:2',3'-d]dibenzofuranyl, xanthene-linked spiroacridinyl, C1-C alkyl-substituted dihydroacridinyl and N-substituted spirofluorene. and phenothiazinyl, phenanthrolinyl, azetidinyl, phenanthridinyl, pteridinyl, naphthyridinyl, furyl, pyranyl, phenoxazinyl, oxazolyl, dioxazolyl, triazolyl, dibenzo[b,f]oxepinyl, benzofuranyl, dibenzofuranyl, thiopyranyl, xanthenyl, chromenyl, isochromenyl, thiazinyl, thienyl, benzothienyl, dibenzothienyl, difuro[3,2-b:2',3'-d]pyridinyl, benzofuro[3,2-b:2',3'-d]dibenzofuranyl, benzothieno[3,2-b:2',3'-d]benzothienyl, benzothieno[3,2-b:2',3'-d]dibenzothienyl, benzothieno[3,2-b:2',3'-d]benzofuranyl, benzothieno[3,2-b:2',3'-d]dibenzofuranyl, xanthene-linked spiroacridinyl, C1-C alkyl-substituted dihydroacridinyl and N-substituted spirofluorene. xanthene-linked spiroacridinyl, C1-C alkyl-substituted dihydroacridinyl and N-substituted spirofluorene. 10 alkyl-substituted dihydroacridinyl and N-substituted spirofluorene.

[0142] As used herein, C6-C 30 arylene may include, but is not limited to, any divalent linking group corresponding to the above aryl groups, and C2-C 30 heteroarylene may include, but is not limited to, any divalent linking group corresponding to the above heteroaryl groups.

[0143] For example, C6-C 30 arylene may include, but is not limited to, phenylene, biphenylene, terphenylenyl, quaterphenylenyl, indenylene, naphthylene, azulylene, indacenylene, acenaphthylene, fluorenylene, spirofluorenylene, phenalenylene, phenanthrylene, anthrylene, fluoranthenylene, triphenylene, pyrenylene, anthracenylene, pentaphenylenyl and / or hexaphenylenyl.

[0144] In another embodiment, C2-C 30Azaaryl groups can include, but are not limited to, pyrrolyl, imidazolyl, pyrazolyl, pyridinyl, pyrazinyl, pyrimidinyl, pyridazinyl, isoindolyl, indolyl, indazolyl, purinyl, quinolinyl, isoquinolinyl, benzoquinolinyl, phthalazinyl, naphthyridinyl, quinoxalinyl, quinazolinyl, benzoisoquinolinyl, benzoquinazolinyl, benzoquinoxalinyl, cinnolinyl, phenanthridinyl, acridinyl, phenanthrolinyl, phenazinyl, benzo azolyl, benzimidazolyl, furyl, benzofuryl, thienyl, benzothienyl, thiazolyl, isothiazolyl, benzothiazolyl, iso azolyl, azolyl, triazolyl, tetrazolyl, diazolyl, triazinyl, dibenzofuryl, dibenzothienyl, carbazolyl, benzocarbazolyl, dibenzocarbazolyl, indolocarbazolyl, indacarbazolyl, imidazopyrimidinyl, and / or imidazopyridinyl.

[0145] As an example, the aryl or aromatic group, heteroaryl or heteroaromatic group, aralkyl, heteroaralkyl, aryloxy, heteroaryloxy, arylamino, and / or heteroarylamino in Chemical Formula 1 and Chemical Formula 4 can each be composed of one to three aromatic rings and / or heteroaromatic rings. When the number of aromatic rings and / or heteroaromatic rings becomes large, the conjugated structure within the entire molecule becomes too long. Therefore, the organic compound may have too narrow a band gap between the highest occupied molecular orbital (HOMO) energy level and the lowest unoccupied molecular orbital (LUMO) energy level.

[0146] For example, the aryl or heteroaryl can each independently include, but are not limited to, phenyl, biphenyl, naphthyl, anthracenyl, pyrrolyl, triazinyl, imidazolyl, pyrazolyl, pyridinyl, pyrazinyl, pyrimidinyl, pyridazinyl, furyl, benzofuryl, dibenzofuryl, thienyl, benzothienyl, dibenzothienyl, carbazolyl, acridinyl, carbolinyl, phenazinyl, phen azinyl, or phenothiazinyl.

[0147] In one embodiment, at least one of R 1 to R 5 in Chemical Formula 1 can be phenyl, carbazolyl, phenyl substituted with carbazolyl, triarylmethyl (e.g., triphenylmethyl), triarylsilyl (e.g., triphenylsilyl), and / or triarylgermyl (e.g., triphenylgermyl), each of which can be independently unsubstituted or substituted. As an example, the first compound 352 having the structure of Chemical Formula 1 can be at least one of the organic compounds of the following Chemical Formula 2 or selected from the organic compounds of the following Chemical Formula 2:

[0148] Chemical formula 2

[0149]

[0150]

[0151]

[0152] In another embodiment, R in Chemical formula 3 11 to R 16 at least one of which may contain an unsubstituted or substituted carbazolyl group. As an example, the first compound 352 having the structure of Chemical formula 3 may be at least one of the following organic compounds of Chemical formula 4 or selected from the following organic compounds of Chemical formula 4:

[0153] Chemical formula 4

[0154]

[0155]

[0156] The second compound 354 may include a triazine-containing organic compound. The second compound 354 includes an organic compound having the structure of the following Chemical formula 5:

[0157] Chemical formula 5

[0158]

[0159] wherein, in Chemical formula 5,

[0160] Z 1 is C, Si or Ge;

[0161] R 21 to R 28 each independently is hydrogen, deuterium, halogen, cyano, unsubstituted or substituted C1 to C 20 alkyl, unsubstituted or substituted C2 to C 20 alkenyl, unsubstituted or substituted C2 to C 20 alkynyl, unsubstituted or substituted C1 to C 20 alkoxy, amino, unsubstituted or substituted C1 to C 20 alkylamino, unsubstituted or substituted C1 to C 20 alkylsilyl, unsubstituted or substituted C4 to C 30 cycloalkyl, unsubstituted or substituted C3 to C 30 heterocycloalkyl, unsubstituted or substituted C6 to C 30 aryl, unsubstituted or substituted C2 to C 30Heteroaryl, unsubstituted or substituted C7 to C 30 Arylalkyl, unsubstituted or substituted C3 to C 30 Heteroarylalkyl, unsubstituted or substituted C6 to C 30 Aryloxy, unsubstituted or substituted C2 to C 30 Heteroaryloxy, unsubstituted or substituted C6 to C 30 Arylamino, unsubstituted or substituted C2 to C 30 Heteroarylamino, unsubstituted or substituted C6 to C 30 Arylsilyl, unsubstituted or substituted C2 to C 30 Heteroarylsilyl, unsubstituted or substituted C1 to C 20 Alkylgermyl, unsubstituted or substituted C6 to C 30 Arylgermyl, unsubstituted or substituted C2 to C 30 Heteroarylgermyl, unsubstituted or substituted C6 to C 30 Triarylmethyl, or unsubstituted or substituted C2 to C 30 Triheteroarylmethyl, wherein when c1 is 2, 3 or 4, each R 21 Are the same or different from each other, when c2 is 2, 3 or 4, each R 22 Are the same or different from each other, when c3 is 2, 3 or 4, each R 23 Are the same or different from each other, when c4 is 2, 3 or 4, each R 24 Are the same or different from each other, when c5 is 2, 3 or 4, each R 25 Are the same or different from each other, when c6 is 2, 3, 4 or 5, each R 26 Are the same or different from each other, when c7 is 2, 3, 4 or 5, each R 27 Are the same or different from each other, and when c8 is 2, 3, 4 or 5, each R 28 Are the same or different from each other;

[0162] c1, c2, c3, c4 and c5 are each independently 0, 1, 2, 3 or 4; and

[0163] c6, c7 and c8 are each independently 0, 1, 2, 3, 4 or 5.

[0164] As an example, the second compound 354 having the structure of Chemical Formula 5 can be, but is not limited to, at least one of the following organic compounds of Chemical Formula 6 or selected from, but not limited to, the following organic compounds of Chemical Formula 6:

[0165] Chemical Formula 6

[0166]

[0167]

[0168] In one embodiment, the first compound 352 and the second compound 354 in the EGL 350 can be mixed at a weight ratio of about 4:1 to about 1:4, such as about 3:1 to about 1:1, but not limited thereto.

[0169] The first host 342 can be a p-type host having beneficial hole affinity properties and / or hole transport properties. The first host 342 can include a carbazole-containing organic compound having a structure of Chemical Formulas 1 to 4. The first host 342 can be the same as or different from the first compound 352.

[0170] The second host 344 can include an n-type host having beneficial electron affinity properties and / or electron transport properties. The second host 344 can have delayed fluorescence properties and can include an organic compound having a structure of the following Chemical Formula 7:

[0171] Chemical Formula 7

[0172]

[0173] Wherein, in Chemical Formula 7,

[0174] R 31 to R 33 are each independently hydrogen, deuterium, halogen, cyano, unsubstituted or substituted C1 to C 20 alkyl, unsubstituted or substituted C2 to C 20 alkenyl, unsubstituted or substituted C2 to C 20 alkynyl, unsubstituted or substituted C1 to C 20 alkoxy, amino, unsubstituted or substituted C1 to C 20 alkylamino, unsubstituted or substituted C1 to C 20 alkylsilyl, unsubstituted or substituted C4 to C 30 cycloalkyl, unsubstituted or substituted C3 to C 30 heterocycloalkyl, unsubstituted or substituted C6 to C 30 aryl, unsubstituted or substituted C2 to C 30 heteroaryl, unsubstituted or substituted C7 to C 30 aralkyl, unsubstituted or substituted C3 to C 30 heteroaralkyl, unsubstituted or substituted C6 to C 30 aryloxy, unsubstituted or substituted C2 to C 30 heteroaryloxy, unsubstituted or substituted C6 to C 30 arylamino, unsubstituted or substituted C2 to C30 Heteroarylamino, unsubstituted or substituted C6 to C 30 Arylsilyl, unsubstituted or substituted C2 to C 30 Heteroarylsilyl, unsubstituted or substituted C1 to C 20 Alkylgermyl, unsubstituted or substituted C6 to C 30 Arylgermyl, unsubstituted or substituted C2 to C 30 Heteroarylgermyl, unsubstituted or substituted C6 to C 30 Triarylmethyl, unsubstituted or substituted C2 to C 30 Triheteroarylmethyl, or has a structure of Formula 8 below, where when d1 is 2, 3 or 4, each R 31 is the same as or different from each other, and when d2 is 2, 3 or 4, each R 32 is the same as or different from each other, d1 and d2 are each independently 0, 1, 2, 3 or 4, where the polycycle containing boron and oxygen has at least one heteroaryl having a structure of Formula 9 below:

[0175] Formula 8

[0176]

[0177] wherein, in Formula 8,

[0178] Z 2 is C, Si or Ge;

[0179] R 34 to R 36 are each independently unsubstituted or substituted C6 to C 30 aryl, unsubstituted or substituted C2 to C 30 heteroaryl, unsubstituted or substituted C7 to C 30 aralkyl, unsubstituted or substituted C3 to C 30 heteroaralkyl, unsubstituted or substituted C6 to C 30 aryloxy, or unsubstituted or substituted C2 to C 30 heteroaryloxy;

[0180] L 1 is a direct bond, unsubstituted or substituted C6 to C 30 arylene or unsubstituted or substituted C2 to C 30 heteroarylene, and

[0181] the wavy line indicates the connection position,

[0182] Formula 9

[0183]

[0184] Among them, in Chemical Formula 9,

[0185] R 41 and R 42 are each independently hydrogen, deuterium, a halogen, a cyano group, an unsubstituted or substituted C1-C 20 alkyl group, an unsubstituted or substituted C2-C 20 alkenyl group, an unsubstituted or substituted C2-C 20 alkynyl group, an unsubstituted or substituted C1-C 20 alkoxy group, an amino group, an unsubstituted or substituted C1-C 20 alkylamino group, an unsubstituted or substituted C1-C 20 alkylsilyl group, an unsubstituted or substituted C4-C 30 cycloalkyl group, an unsubstituted or substituted C3-C 30 heterocycloalkyl group, an unsubstituted or substituted C6-C 30 aryl group, an unsubstituted or substituted C2-C 30 heteroaryl group, an unsubstituted or substituted C7-C 30 aralkyl group, an unsubstituted or substituted C3-C 30 heteroaralkyl group, an unsubstituted or substituted C6-C 30 aryloxy group, an unsubstituted or substituted C2-C 30 heteroaryloxy group, an unsubstituted or substituted C6-C 30 arylamino group, an unsubstituted or substituted C2-C 30 heteroarylamino group, an unsubstituted or substituted C6-C 30 arylsilyl group, an unsubstituted or substituted C2-C 30 heteroarylsilyl group, an unsubstituted or substituted C1-C 20 alkylgermyl group, an unsubstituted or substituted C6-C 30 arylgermyl group, an unsubstituted or substituted C2-C 30 heteroarylgermyl group, an unsubstituted or substituted C6-C 30 triarylmethyl group, or an unsubstituted or substituted C2-C 30 triheteroarylmethyl group, where when e1 is 2, 3 or 4, each R 41 is the same as or different from each other, and when e2 is 2, 3 or 4, each R 42 is the same as or different from each other, e1 and e2 are each independently 0, 1, 2, 3 or 4, or

[0186] Optionally,

[0187] two adjacent Rs 41and / or two adjacent Rs 42 are further linked together to form an unsubstituted or substituted C4 - C 20 alicyclic ring, an unsubstituted or substituted C3 - C 20 heteroalicyclic ring, an unsubstituted or substituted C6 - C 20 aromatic ring, or an unsubstituted or substituted C2 - C 20 heteroaromatic ring; and

[0188] The wavy line indicates the connection position.

[0189] As an example, the fused ring formed by two adjacent Rs 41 and / or two adjacent Rs 42 in Formula 9 may include, but are not limited to, an indene ring, an indole ring, a benzofuran ring, and / or a benzothiophene ring, each of which may be independently unsubstituted or substituted.

[0190] The polycycle containing boron and oxygen in the second host 344 having the structure of Formula 7 acts as an electron - acceptor part or an electron - withdrawing part. The heteroaryl having the structure of Formula 9 acts as an electron - donor part. Due to the large volume of the electron - donor parts of the plural fused rings, steric hindrance occurs between these parts. Therefore, the second compound 354 having the structure of Formula 7 has delayed fluorescence characteristics. For example, the second host 344 may have a narrow difference or energy band gap ΔE ST between its lowest - excited singlet - state energy level S1 and its lowest - excited triplet - state energy level T1, for example, about 0.3 eV, for example, from about 0.01 eV to about 0.3 eV.

[0191] Since the second host 344 having the structure of Formula 7 has a very narrow difference or energy band gap ΔE ST between its lowest - excited singlet - state energy level S1 and its lowest - excited triplet - state energy level T1, the spin - orbital coupling (SOC) within the molecule can be enhanced. Therefore, reverse intersystem crossing (RISC) (up - conversion from the lowest - excited triplet - state energy level T1 to the lowest - excited singlet - state energy level S1) can occur rapidly within the molecule.

[0192] In one embodiment, the second host 344 having the structure of Formula 7 may contain one to three heteroaryls having the structure of Formula 9 substituted onto the polycycle containing boron and oxygen. For example, the Rs in Formula 7 31 to R 33One to three of them can be heteroaryl groups having the structure of Chemical Formula 9. In another embodiment, the heteroaryl group having the structure of Chemical Formula 9 can be unsubstituted or substituted with one to five, for example, one to three, or one or two carbazolyl groups or phenyl groups, and the carbazolyl group and the phenyl group can be further substituted with deuterium.

[0193] As an example, the second host 344 having the structure of Chemical Formula 7 can be at least one of the following organic compounds of Chemical Formula 10 or selected from the following organic compounds of Chemical Formula 10:

[0194] Chemical Formula 10

[0195]

[0196]

[0197]

[0198]

[0199] In one embodiment, the light emitter 346 can include at least one of a blue phosphorescent material, a blue fluorescent material, and a blue delayed fluorescent material. As an example, the light emitter 346 can include a blue phosphorescent material. For example, the light emitter 346 can include an organometallic compound having the structure of the following Chemical Formula 11:

[0200] Chemical Formula 11

[0201]

[0202] Wherein, in Chemical Formula 11,

[0203] R 51 to R 56 are each independently hydrogen, deuterium, halogen, cyano, unsubstituted or substituted C1 to C 20 alkyl, unsubstituted or substituted C2 to C 20 alkenyl, unsubstituted or substituted C2 to C 20 alkynyl, unsubstituted or substituted C1 to C 20 alkoxy, amino, unsubstituted or substituted C1 to C 20 alkylamino, unsubstituted or substituted C1 to C 20 alkylsilyl, unsubstituted or substituted C4 to C 30 cycloalkyl, unsubstituted or substituted C3 to C 30 heterocycloalkyl, unsubstituted or substituted C6 to C 30 aryl, unsubstituted or substituted C2 to C 30Heteroaryl, unsubstituted or substituted C7 to C 30 Arylalkyl, unsubstituted or substituted C3 to C 30 Heteroarylalkyl, unsubstituted or substituted C6 to C 30 Aryloxy, unsubstituted or substituted C2 to C 30 Heteroaryloxy, unsubstituted or substituted C6 to C 30 Arylamino, unsubstituted or substituted C2 to C 30 Heteroarylamino, unsubstituted or substituted C6 to C 30 Arylsilyl, unsubstituted or substituted C2 to C 30 Heteroarylsilyl, unsubstituted or substituted C1 to C 20 Alkylgermyl, unsubstituted or substituted C6 to C 30 Arylgermyl, unsubstituted or substituted C2 to C 30 Heteroarylgermyl, unsubstituted or substituted C6 to C 30 Triarylmethyl, or unsubstituted or substituted C2 to C 30 Triheteroarylmethyl, wherein when f1 is 2, 3 or 4, each R 51 Are the same as or different from each other, when f2 is 2, 3 or 4, each R 52 Are the same as or different from each other, when f3 is 2, each R 53 Are the same as or different from each other, when f4 is 2 or 3, each R 54 Are the same as or different from each other, and when f5 is 2, 3 or 4, each R 55 Are the same as or different from each other;

[0204] f1, f2 and f5 are each independently 0, 1, 2, 3 or 4;

[0205] f3 is 0, 1 or 2; and

[0206] f4 is 0, 1, 2 or 3.

[0207] As an example, the luminescent body 346 having the structure of Chemical Formula 11 can be at least one of, but not limited to, the following organometallic compounds of Chemical Formula 12 or selected from, but not limited to, the following organometallic compounds of Chemical Formula 12:

[0208] Chemical Formula 12

[0209]

[0210]

[0211]

[0212] The content of the host including the first host 342 and the second host 344 in the EML 340 can be from about 50 wt% to about 99 wt%, such as from about 50 wt% to about 90 wt% or from about 60 wt% to about 90 wt%. The content of the emitter 346 in the EML 340 can be from about 1 wt% to about 50 wt%, such as from about 10 wt% to about 50 wt% or from about 10 wt% to about 40 wt%, but is not limited thereto. The first host 342 and the second host 344 in the EML 340 can be mixed at a weight ratio of about 4:1 to about 1:4, such as about 3:1 to about 1:3, but is not limited thereto.

[0213] The HIL 310 is disposed between the first electrode 210 and the HTL 320, and can improve the interfacial characteristics between the inorganic first electrode 210 and the organic HTL 320. In one embodiment, the hole injection material in the HIL 310 can include, 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-(naphthalen-1-yl)-N-phenyl-amino)triphenylamine (1T-NATA), 4,4',4”-tris(N-(naphthalen-2-yl)-N-phenyl-amino)triphenylamine (2T-NATA), copper phthalocyanine (CuPc), tris(4-carbazol-9-yl-phenyl)amine (TCTA), N,N'-diphenyl-N,N'-bis(1-naphthyl)-1,1'-biphenyl-4,4”-diamine (NPB; NPD), N,N'-bis{4-[bis(3-methylphenyl)amino]phenyl}-N,N'-diphenyl-4,4'-biphenyldiamine (DNTPD), 1,4,5,8,9,11-hexaazatriphenylenehexacarbonitrile (dipyrazino[2,3-f:2'3'-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile; HAT-CN), 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ), 1,3,4,5,7,8-hexafluorotetracyano-naphthoquinodimethane (F6-TCNNQ), 1,3,5-tris[4-(diphenylamino)phenyl]benzene (TDAPB), poly(3,4-ethylenedioxythiophene)polystyrenesulfonate (PEDOT / PSS), N-(biphenyl-4-yl)-9,9-dimethyl-N-(4-(9-phenyl-9H-carbazol-3-yl)phenyl)-9H-fluorene-2-amine, N,N'-diphenyl-N,N'-bis[4-(N,N'-diphenyl-amino)phenyl]benzidine (NPNPB), and / or combinations thereof.

[0214] In another embodiment, the HIL 310 may include a hole injection host of the following hole transport materials and a hole injection dopant of the above hole injection materials (e.g., HAT-CN, F4-TCNQ, and / or F6-TCNNQ). In this case, the content of the hole injection dopant in the HIL 310 may be, but is not limited to, about 1 wt% to about 10 wt%. In certain embodiments, the HIL 310 may be omitted in accordance with the OLED D1 characteristics.

[0215] The HTL 320 is disposed adjacent to the EML 340 between the first electrode 210 and the EML 340. In one embodiment, the hole transport material in the HTL 320 may include, but is not limited to, N,N'-diphenyl-N,N'-bis(3-methylphenyl)-1,1'-biphenyl-4,4'-diamine (TPD), NPB (NPD), DNTPD, 4,4'-bis(N-carbazolyl)-1,1'-biphenyl (CBP), poly[N,N'-bis(4-butylphenyl)-N,N'-bis(phenyl)-benzidine] (poly-TPD), poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(4,4'-(N-(4-sec-butylphenyl)diphenylamine))] (TFB), bis-[4-(N,N-di-p-tolyl-amino)phenyl)cyclohexane (TAPC), 3,5-bis(9H-carbazol-9-yl)-N,N-diphenylaniline (DCDPA), N-(biphenyl-4-yl)-9,9-dimethyl-N-(4-(9-phenyl-9H-carbazol-3-yl)phenyl)-9H-fluorene-2-amine, N-(biphenyl-4-yl)-N-(4-(9-phenyl-9H-carbazol-3-yl)phenyl)biphenyl-4-amine), N-([1,1'-biphenyl]-4-yl)-9,9-dimethyl-N-(4-(9-phenyl-9H-carbazol-3-yl)phenyl)-9H-fluorene-2-amine, and / or combinations thereof.

[0216] The ETL 370 and the EIL 380 may be sequentially laminated between the EML 340 and the second electrode 220. The electron transport material contained in the ETL 370 has a high electron mobility to stably supply electrons to the EML 340 through rapid electron transport.

[0217] The electron transport material in the ETL 370 may include at least one of the following: containing compounds containing a diazole, compounds containing a triazole, compounds containing a phenanthroline, containing a benz azole compounds, compounds containing a benzothiazole, compounds containing a benzimidazole, and compounds containing a triazine.

[0218] For example, the electron transport material in the ETL 370 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 quinolate (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(naphthalen-2-yl)-4,7-diphenyl-1,10-phenanthroline (NBphen), 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), 2-phenyl-9-(3-(2-phenyl-1,10-phenanthrolin-9-yl)phenyl)-1,10-phenanthroline, 3-(4-biphenylyl)-4-phenyl-5-tert-butylphenyl-1,2,4-triazole (TAZ), 4-(naphthalen-1-yl)-3,5-diphenyl-4H-1,2,4-triazole (NTAZ), 1,3,5-tris(pyridin-3-yl-phenyl)benzene (TpPyPB), 2,4,6-tris(3'-(pyridin-3-yl)biphenyl-3-yl)-1,3,5-triazine (TmPPPyTz), poly[9,9-bis(3'-((N,N-dimethyl)-N-ethylammonium)-propyl)-2,7-fluorene-alt-2,7-(9,9-dioctylfluorene)] (PFNBr), tris(phenylquinoxaline) (TPQ), TSPO1, 2-[4-(9,10-di-2-naphthalen-2-yl-2-anthracen-2-yl)phenyl]-1-phenyl-1H-benzimidazole (ZADN), and / or combinations thereof.

[0219] The EIL 380 is disposed between the second electrode 220 and the ETL 370, and can improve the physical properties of the second electrode 220, and thus can increase the lifespan of the OLED D1. In one embodiment, the electron injection material in the EIL 380 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 Liq, lithium benzoate, sodium stearate, etc. In certain embodiments, the EIL 380 may be omitted.

[0220] In another embodiment, the ETL 370 and the EIL 380 may have a single-layer structure. In this case, the above electron transport materials and / or electron injection materials may be mixed with each other. As an example, the ETL / EIL having a single-layer structure may contain two or more different electron transport materials. For example, two electron transport materials in the ETL / EIL are mixed at a weight ratio of about 3:7 to about 7:3, but are not limited thereto.

[0221] When holes are transferred to the second electrode 220 via the EML 340 and / or electrons are transferred to the first electrode 210 via the EML 340, the OLED D1 may have a short lifetime and reduced luminous efficiency. To prevent those phenomena, the OLED D1 according to this aspect of the present disclosure may have at least one exciton blocking layer adjacent to the EML 340.

[0222] As an example, the OLED D1 may include an EBL 330 between the HTL 320 and the EML 340 to control and prevent electron transfer. In one embodiment, the electron blocking material in the EBL 330 may include, but is not limited to, TCTA, tris[4-(diethylamino)phenyl]amine, N-(biphenyl-4-yl)-9,9-dimethyl-N-(4-(9-phenyl-9H-carbazol-3-yl)phenyl)-9H-fluorene-2-amine, TAPC, MTDATA, mCP, mCBP, CuPc, DNTPD, TDAPB, DCDPA, 2,8-bis(9-phenyl-9H-carbazol-3-yl)dibenzothiophene, and / or combinations thereof. In another embodiment, the electron blocking material in the EBL 330 may contain a carbazole-containing organic compound having a structure of Chemical Formula 1 to Chemical Formula 4.

[0223] In addition, the OLED D1 may further include an HBL 360 as a second exciton blocking layer between the EML 340 and the ETL 370, such that holes cannot be transferred from the EML 340 to the ETL 370. In one embodiment, the hole blocking material in the HBL 360 may include, but is not limited to, at least one of the following: compounds containing diazole, compounds containing triazole, compounds containing phenanthroline, compounds containing benz azole, compounds containing benzothiazole, compounds containing benzimidazole, and compounds containing triazine.

[0224] As an example, the hole blocking material in HBL 360 may include a material having a relatively low HOMO energy level compared to the light emitting material in EML 340. For example, the hole blocking material in HBL 360 may include, but is not limited to, BCP, BAlq, Alq3, PBD, spiro-PBD, Liq, bis-4,5-(3,5-di-3-pyridylphenyl)-2-methylpyrimidine (B3PYMPM), DPEPO, 9-(6-(9H-carbazol-9-yl)pyridin-3-yl)-9H-3,9'-bicarbazole, TSPO1, and / or a combination thereof. In another embodiment, the hole blocking material in HBL 360 may comprise an organic compound having the structures of Chemical Formula 7 and Chemical Formula 10. In certain embodiments, EBL 330 and / or HBL 360 may be omitted in accordance with OLED D1.

[0225] In Figure 3 the first embodiment shown in, EGL 350 is disposed between the first electrode 210 and the EML 340. Alternatively, the exciton generation layer may be disposed between the light emitting material layer and the second electrode. Figure 4 A cross-sectional view of an organic light emitting diode having a single light emitting portion according to another embodiment of the present disclosure is shown.

[0226] As Figure 4 shown, an organic light emitting diode D2 (OLED D2) according to another embodiment includes a first electrode 210, a second electrode 220 facing the first electrode 210, and a light emitting layer 230A disposed between the first electrode 210 and the second electrode 220. The organic light emitting display device 100 includes a red pixel region, a green pixel region, and a blue pixel region, and the OLED D2 may be disposed in the red pixel region, the green pixel region, and / or the blue pixel region. As an example, the OLED D2 may be disposed in the blue pixel region.

[0227] In one embodiment, the light-emitting layer 230A includes a light-emitting material layer (EML) 340 disposed between the first electrode 210 and the second electrode 220, and an exciton generation layer (EGL) 350 disposed between the EML 340 and the second electrode 220, such as between the EML 340 and a hole blocking layer (HBL) 360 or an electron transport layer (ETL) 370. The light-emitting layer 230A may include at least one of a hole transport layer (HTL) 320 disposed between the first electrode 210 and the EML 340 and an ETL 370 disposed between the second electrode 220 and the EML 340. In certain embodiments, the light-emitting layer 230A may further include at least one of a hole injection layer (HIL) 310 disposed between the first electrode 210 and the HTL 320 and an electron injection layer (EIL) 380 disposed between the second electrode 220 and the ETL 370. Alternatively or additionally, the light-emitting layer 230A may further include an electron blocking layer (EBL) 330 disposed between the HTL 320 and the EML 340 and / or an HBL 360 disposed between the EML 340 and the ETL 370, such as between the EGL 350 and the ETL 370.

[0228] The configuration of the first electrode 210, the second electrode 220, and the light-emitting layer 230A other than the EGL 350 disposed between the EML 340 and the second electrode 220 may be the same as the configuration shown in Figure 3 The EGL 350 contains a first compound 352 and a second compound 354. The first compound 352 may include a carbazole-containing organic compound having a structure of Chemical Formula 1 to Chemical Formula 4. The second compound 354 may include a triazine-containing organic compound having a structure of Chemical Formula 5 to Chemical Formula 6.

[0229] The EML 340 contains a first host 342, a second host 344, and a light emitter 346. The first host 342 may include a carbazole-containing organic compound having a structure of Chemical Formula 1 to Chemical Formula 4. The second host 344 may include an organic compound having a structure of Chemical Formula 7 and Chemical Formula 10 and having delayed fluorescence characteristics. The light emitter 346 may include an organometallic compound having a structure of Chemical Formula 11 to Chemical Formula 12.

[0230] The content of the first compound 352 and the second compound 354 in the EGL 350 and / or the content of the first host 342, the second host 344, and the light emitter 346 in the EML 340 may be the same as the corresponding content with reference to Figure 3 In another embodiment, the exciton generation layer may be disposed between the first electrode and the light-emitting material layer and between the light-emitting material layer and the second electrode.

[0231] Figure 5A cross-sectional view of an organic light-emitting diode having a single light-emitting portion according to another embodiment of the present disclosure is shown.

[0232] As Figure 5 shown, an organic light-emitting diode D3 (OLED D3) according to another embodiment includes a first electrode 210, a second electrode 220 facing the first electrode 210, and a light-emitting layer 230B disposed between the first electrode 210 and the second electrode 220. The organic light-emitting display device 100 includes a red pixel region, a green pixel region, and a blue pixel region, and the OLED D3 may be disposed in the red pixel region, the green pixel region, and / or the blue pixel region. As an example, the OLED D3 may be disposed in the blue pixel region.

[0233] In one embodiment, the light-emitting layer 230B includes a light-emitting material layer (EML) 340 disposed between the first electrode 210 and the second electrode 220, and a first exciton generation layer (EGL1) 350A disposed between the first electrode 210 and the EML 340, such as between a hole transport layer (HTL) 320 or an electron blocking layer (EBL) 330 and the EML 340. The light-emitting layer 230B includes a second exciton generation layer (EGL2) 350B disposed between the EML 340 and the second electrode 220, such as between the EML 340 and a hole blocking layer (HBL) 360 or an electron transport layer (ETL) 370. The light-emitting layer 230B may include at least one of the HTL 320 disposed between the first electrode 210 and the EML 340 and the ETL 370 disposed between the second electrode 220 and the EML 340. In certain embodiments, the light-emitting layer 230B may further include at least one of a hole injection layer (HIL) 310 disposed between the first electrode 210 and the HTL 320 and an electron injection layer (EIL) 380 disposed between the second electrode 220 and the ETL 370. Alternatively or additionally, the light-emitting layer 230B may further include a first exciton blocking layer, i.e., the EBL 330, disposed between the HTL 320 and the EML 340, such as between the HTL 320 and the EGL1 350A, and / or an HBL 360 disposed between the EML 340 and the ETL 370, such as between the EGL2 350B and the ETL 370.

[0234] The configuration of the first electrode 210, the second electrode 220, and the light-emitting layer 230B other than the EGL2 350B disposed between the EML 340 and the second electrode 220 may be the same as Figure 3The configurations shown in [reference] are the same. EGL1 350A includes a first compound 352a and a second compound 354a, and EGL2 350B includes a third compound 352b and a fourth compound 354b. Each of the first compound 352a and the third compound 352b may independently include a carbazole-containing organic compound having a structure of Chemical Formula 1 to Chemical Formula 4. Each of the second compound 354a and the fourth compound 354b may independently include a triazine-containing organic compound having a structure of Chemical Formula 5 to Chemical Formula 6.

[0235] The first compound 352a may be the same as or different from the third compound 352b. The second compound 354a may be the same as or different from the fourth compound 354b. In one embodiment, the first compound 352a and the second compound 354a in EGL1 350A may be mixed at a weight ratio of about 4:1 to about 1:4, such as about 3:1 to about 1:3, but not limited thereto. In another embodiment, the third compound 352b and the fourth compound 354b in EGL2 350B may be mixed at a weight ratio of about 4:1 to about 1:4, such as about 3:1 to about 1:3, but not limited thereto.

[0236] The materials or contents of the first host 342, the second host 344, and the light emitter 346 in the EML 340 may be the same as the corresponding materials and contents with reference to Figure 3 thereof.

[0237] By forming at least one exciton generation layer capable of generating an exciplex adjacent to the light-emitting material layer containing the delayed fluorescence host, the organic light-emitting diode can reduce its driving voltage and can maximize its luminous lifetime.

[0238] Figure 6 is a schematic diagram of a light-emitting mechanism in the case where an exciton generation layer is formed adjacent to the light-emitting material layer according to an embodiment of the present disclosure.

[0239] As Figures 3 to 6 shown, the EML 340 includes a second host 344 having delayed fluorescence characteristics. The second host 344 can utilize both singlet exciton energy and triplet exciton energy through intersystem crossing (ISC) and reverse intersystem crossing (RISC) mechanisms. When the EML 340 includes a light emitter 346 having appropriate energy levels compared to the first host 342 and / or the second host 344, the light emitter 346 can absorb the exciton energy released from the first host 342 and the second host 344, so that the light emitter 346 can maximize its luminous efficiency by using the absorbed exciton energy.

[0240] For example, when the light emitter 346 is a phosphorescent material, the triplet exciton energy of the first host 342 and the second host 344 with delayed fluorescence characteristics can be transferred to the light emitter 346 through the Dexter energy transfer (DET) mechanism, and the singlet exciton energy of the first host 342 and the second host 344 can be transferred to the light emitter 346 through the Forster resonance energy transfer (FRET) mechanism.

[0241] In addition, an exciplex is generated between the first compound 352 (352a or P-EGL) and the second compound 354 (354a or N-EGL), or between the third compound 352b (P-EGL) and the fourth compound 354b (N-EGL) within the EGLs 350, 350A, or 350B disposed adjacent to the EML 340. The triplet exciton energy of the exciplex generated in the EGLs 350, 350A, or 350B can be transferred to the light emitter 346 of the EML 340, which is an organic layer disposed adjacent to the EGLs 350, 350A, or 350B, through the DET mechanism, and the singlet exciton energy of the exciplex generated in the EGLs 350, 350A, or 350B can be transferred to the light emitter 346 through the FRET mechanism. The light emitter 346 of the phosphorescent material can emit using both singlet excitons and triplet excitons transferred from the first host 342 and / or the second host 344 and the exciplex.

[0242] In one embodiment, the photoluminescence wavelength and absorption wavelength of the first compound 352 or 352a and / or the third compound 352b of the P-type exciton generating compound P-EGL, and the second compound 354 or 354a and / or the fourth compound 354b of the N-type exciton generating compound N-EGL can be controlled such that the EGLs 350, 350A, or 350B can generate an exciplex, and the exciton energy can be transferred from the generated exciplex to the EML 340. As an example, the maximum photoluminescence wavelength of the exciton generating compound EGL can be longer than the maximum photoluminescence wavelength of the N-type exciton generating compound N-EGL. In other words, the maximum photoluminescence wavelength of the exciton generating compound EGL and the maximum photoluminescence wavelength of the N-type exciton generating compound N-EGL can satisfy the condition in the following formula (1):

[0243] λmax(EGL) > λmax(N-EGL) (1)

[0244] Among them, in Formula (1), λmax(EGL) represents the maximum photoluminescence wavelength of the exciton-generating compound in which a P-type exciton-generating compound and an N-type exciton-generating compound are mixed, and λmax(N-EGL) represents the maximum photoluminescence wavelength of the N-type exciton-generating compound.

[0245] In another embodiment, the difference between the starting wavelength in the absorption (Abs) spectrum of the light emitter 346 and the starting wavelength in the photoluminescence (PL) spectrum of the exciplex should be greater than about 10 nm. As used herein, the starting wavelength is the wavelength value of the point where the X-axis (wavelength) intersects the extrapolated line in the linear region of the short-wavelength region of the Abs spectrum or PL spectrum of the organic compound. As an example, the starting wavelength can be defined as the wavelength corresponding to the shorter of two wavelengths in the Abs spectrum or PL spectrum, where the emission intensity is 1 / 5 to 1 / 15 (e.g., 1 / 10) of the maximum emission intensity. That is, the difference between the starting wavelength at the Abs spectrum of the light emitter 346 and the starting wavelength at the PL spectrum of the exciplex can satisfy the condition in the following Formula (2).

[0246] λstart Abs (light emitter) - λstart PL (EGL) > 10 nm (2) Among them, in Formula (2), λstart Abs (light emitter) represents the starting wavelength in the absorption spectrum of the light emitter, and λstart PL (EGL) represents the starting wavelength in the phosphorescence spectrum of the exciton-generating compound in which a P-type exciton-generating compound and an N-type exciton-generating compound are mixed.

[0247] In another embodiment, by preventing the reverse transfer of exciton energy from the light emitter 346 to the exciplex, the light emitter 346 can maximize its internal quantum efficiency. As an example, the starting wavelength in the PL spectrum of the light emitter 346 can be longer than the starting wavelength of the PL spectrum of the exciplex. That is, the starting wavelength in the PL spectrum of the light emitter 346 and the starting wavelength in the PL spectrum of the exciplex can satisfy the condition in the following Formula (3).

[0248] λstart PL (light emitter) > λstart PL (EGL) (3) Among them, in Formula (3), λstart PL (light emitter) represents the starting wavelength in the photoluminescence spectrum of the light emitter, and λstart PL (EGL) represents the starting wavelength in the phosphorescence spectrum of the exciton-generating compound in which a P-type exciton-generating compound and an N-type exciton-generating compound are mixed.

[0249] In another embodiment, the lowest excited triplet energy levels of the first compound 352 or 352a and / or the third compound 352b, the second compound 354 or 354a, and the fourth compound 354b may satisfy the conditions in the following formula (4).

[0250] T1(P-EGL)>T1(N-EGL)>T1(host 2)>T1(emitter) (4) Wherein, in formula (4), T1(P-EGL) represents the lowest excited triplet energy level of the first compound and / or the third compound, T1(N-EGL) represents the lowest excited triplet energy level of the second compound and / or the fourth compound, T1(host 2) represents the lowest excited triplet energy level of the second host, and T1(emitter) represents the lowest excited triplet energy level of the emitter.

[0251] In another embodiment, the HOMO energy levels and / or LUMO energy levels of the first host 342, the second host 344, and the emitter 346 in the EML 340, and the first compound 352 or 352a, the second compound 354 or 354a, the third compound 352b, and the fourth compound 354b in the EGL 350, 350A or 350B are adjusted such that holes and electrons can be rapidly injected into the EML 340. Figure 7 Schematic diagrams of the HOMO energy levels and LUMO energy levels of the first compound and the second compound in the exciton generation layer and the first host and the second host in the light-emitting material layer. Figure 8 Schematic diagram of charge injection into the light-emitting material layer in the case of generating an exciplex in the exciton generation layer according to an embodiment of the present disclosure. Figure 9 Schematic diagram of ineffective charge injection into the light-emitting material layer due to the barrier voltage in the case where an organic layer disposed adjacent to the light-emitting material layer cannot generate an exciplex.

[0252] As Figure 7 shown, the HOMO energy level HOMO of the first compound and / or the third compound of the P-type exciton generating compound P-EGL P-EGL and the HOMO energy level HOMO of the first host PH PH and the HOMO energy level HOMO of the second host NH NH The difference or energy band gap ΔHOMO between the higher HOMO energy levels, for example, the HOMO energy level HOMO of the first host PH PH 1 ​It can be about 0.3 eV or less. In this case, holes can be quickly injected from the EGL into the EML. That is, the HOMO energy levels of the first compound and / or the third compound of the P-type compound P-EGL in the EGL and the HOMO energy levels of the host PH or NH in the EML can satisfy the conditions in the following formula (5).

[0253] |HOMO 主体-H –HOMO P-EGL |≤0.3 eV (5)

[0254] Among them, in formula (5), HOMO 主体-H represents the higher HOMO energy level among the HOMO energy levels of the first host and the second host. For example, when the HOMO energy level of the first host is higher than the HOMO energy level of the second host, HOMO 主体-H can be the HOMO energy level of the first host, and when the HOMO energy level of the second host is higher than the HOMO energy level of the first host, HOMO 主体-H can be the HOMO energy level of the second host, and HOMO P-EGL represents the HOMO energy level of the P-type exciton generating compound.

[0255] In another embodiment, the difference in the energy band gap ΔHOMO P-EGL between the HOMO energy level HOMO N-EGL of the P-type exciton generating compound P-EGL in the EGL and the HOMO energy level HOMO 2 of the N-type exciton generating compound N-EGL can be about 0.2 eV or greater and about 0.8 eV or less. In this case, an exciplex can be generated between the P-type exciton generating compound P-EGL and the N-type exciton generating compound N-EGL. That is, the HOMO energy level HOMO P-EGL of the P-type exciton generating compound P-EGL and the HOMO energy level HOMO N-EGL of the N-type exciton generating compound N-EGL can satisfy the conditions in the following formula (6).

[0256] 0.2 eV≤|HOMO P-EGL –HOMO N-EGL |≤0.8 eV (6)

[0257] In another embodiment, the LUMO energy level of the second compound and / or the fourth compound of the N-type exciton generating compound N-EGL and the lower LUMO energy level among the LUMO energy level LUMO PH of the first host PH and the LUMO energy level HOMO NH of the second host NH, for example, the LUMO energy level LUMO of the second host NHNH The difference or band gap ΔLUMO between 1 can be about 0.3 eV or less. In this case, electrons can be rapidly injected from the EGL into the EML. That is, the LUMO levels of the second and / or fourth compounds of the N-type compound N-EGL in the EGL and the LUMO level of the host PH or NH in the EML can satisfy the conditions in the following formula (7).

[0258] |LUMO 主体-L – LUMO N-EGL | ≤ 0.3 eV (7)

[0259] Wherein, in formula (7), LUMO 主体-L represents the lower LUMO level among the LUMO levels of the first host and the second host. For example, in the case where the LUMO level of the first host is lower than the LUMO level of the second host, LUMO 主体-L can be the LUMO level of the first host, and in the case where the LUMO level of the second host is lower than the LUMO level of the first host, LUMO 主体-L can be the LUMO level of the second host, and LUMO N-EGL represents the LUMO level of the N-type exciton generating compound.

[0260] In another embodiment, the difference in band gap ΔLUMO between the LUMO level LUMO P-EGL of the P-type exciton generating compound P-EGL in the EGL and the LUMO level LUMO N-EGL of the N-type exciton generating compound N-EGL 2 can be about 0.2 eV or greater and about 0.8 eV or less. In this case, an exciplex can be generated between the P-type exciton generating compound P-EGL and the N-type exciton generating compound N-EGL. That is, the LUMO level LUMO P-EGL of the P-type exciton generating compound P-EGL and the LUMO level LUMO N-EGL of the N-type exciton generating compound N-EGL can satisfy the conditions in the following formula (8).

[0261] 0.2 eV ≤ |LUMO P-EGL – LUMO N-EGL | ≤ 0.8 eV (8)

[0262] As Figure 8As shown, when adjusting the energy levels in the luminescent material in the EML 340, and in the P-type exciton generation compounds 352, 352a, and / or 352b and the N-type exciton generation compounds 354, 354a, and / or 354b, and thus generating exciplexes in the EGL1, EGL2, 350, 350A, and / or 350B, holes and electrons can be rapidly injected from the EGL1 and / or EGL2 into the EML 340.

[0263] In contrast, as Figure 9 shown, when no exciplex is generated in the organic layer disposed adjacent to the EML, holes and / or electrons cannot be effectively injected into the EML due to the barrier voltage between the non-EGL1 and / or non-EGL2 and the EML.

[0264] The voltage required to inject charges from an electrode into a luminescent material layer in an organic light-emitting diode is proportional to the band gaps of the luminescent material and the charge transport material. The band gap of the host 342 or 344 in the EML 340 is proportional to the lower excited singlet state energy level of the host 342 or 344.

[0265] As described above, the EML 340 includes a second host 344 having delayed fluorescence characteristics. When determining the required excited triplet state energy level of the host, as the difference between the excited singlet state energy level and the excited triplet state energy level becomes smaller, the band gap of the host decreases. The second host 344 has a very small energy band gap ΔE between its excited singlet state energy level and its excited triplet state energy level ST , and thus, the energy required for exciton recombination in the second host 344 can be reduced. Since the EML 340 includes the second host 344 having delayed fluorescence characteristics, the voltage required to inject charges from an electrode into the EML 340 can be reduced.

[0266] In addition, similar to the host 342 and / or 344, the exciplexes generated in the EGL 350, 350A, and / or 350B can transfer exciton energy to the light emitter 346. Since the exciplexes can have delayed fluorescence characteristics, the energy required for exciton recombination can be reduced, and the voltage required to inject charges from an electrode into the EML 340 can be further reduced. The OLEDs D1, D2, and / or D3 in which the EML 340 includes the second host 344 having delayed fluorescence characteristics and at least one of the EGL 350, 350A, and 350B that can generate exciplexes disposed adjacent to the EML 340 can reduce their driving voltage and reduce their power consumption.

[0267] Figure 10Schematic diagram of a light-emitting region and a recombination region in the case where an exciton generation layer is not formed adjacent to a light-emitting material layer. In the case where the EML contains a phosphorescent material as a light emitter, the light-emitting region and the exciton recombination region can be extended by increasing the thickness of the EML. As the thickness of the EML increases, the exciton recombination region is extended to a region in the EML having a lower out-coupling efficiency. Therefore, the external quantum efficiency (EQE) in the EML is reduced. In addition, as the EML becomes wider, the amount of expensive phosphorescent material used increases, which results in an increase in material cost.

[0268] Figure 11 Schematic diagram of a light-emitting region and a recombination region in the case where an exciton generation layer is formed adjacent to a light-emitting material layer according to an embodiment of the present disclosure. As Figure 11 shown, exciton generation layers EGL1 and EGL2 are arranged adjacent to the EML. The exciton generation layers EGL1 and EGL2 are arranged at regions having a lower out-coupling efficiency. In this case, an exciton recombination region is formed within the EML and extends to the exciton generation layers EGL1 and EGL2 provided adjacent to the EML. Since the exciton recombination region is extended, the exciton concentration or energy level in the EML can be reduced. Since the amount of non-emitting excitons or quenched excitons can be minimized, the deterioration of the light-emitting material and the charge transport material caused by non-emitting excitons can be minimized. Therefore, the light-emitting lifetime of the OLEDs D1, D2, and D3 can be maximized.

[0269] On the contrary, the light-emitting region is limited to a region in the EML having a beneficial out-coupling efficiency. Since the light-emitting material emits light within the EML with a beneficial out-coupling efficiency, the external quantum efficiency (EQE) of the OLEDs D1, D2, and D3 can be improved. Since it is not necessary to extend the EML region, the amount of phosphorescent material used can be reduced. Therefore, the material cost can be reduced.

[0270] Figures 2 to 5 An organic light-emitting device and OLEDs D1, D2, and D3 having a single light-emitting portion and emitting blue light are shown. In another embodiment, the organic light-emitting display device can achieve full color including white. Figure 12 A schematic cross-sectional view of an organic light-emitting display device according to another embodiment of the present disclosure is shown.

[0271] As Figure 12 shown, the organic light-emitting display device 400 includes: a first substrate 402 that defines each of a red pixel region RP, a green pixel region GP, and a blue pixel region BP; a second substrate 404 facing the first substrate 402; a thin-film transistor Tr on the first substrate 402; an OLED D that is provided between the first substrate 402 and the second substrate 404 and emits white (W) light; and a color filter layer 480 provided between the OLED D and the second substrate 404.

[0272] The first substrate 402 and the second substrate 404 may each include, but are not limited to, glass, flexible materials, and / or polymer plastics. For example, the first substrate 402 and the second substrate 404 may each be made of PI, PES, PEN, PET, PC, and / or combinations thereof. In certain embodiments, the second substrate 404 may be omitted. The first substrate 402 on which thin film transistors Tr and OLED Ds are disposed forms an array substrate.

[0273] A buffer layer 406 may be provided on the first substrate 402. The thin film transistors Tr are disposed on the buffer layer 406 corresponding to each of the red pixel region RP, the green pixel region GP, and the blue pixel region BP. In certain embodiments, the buffer layer 406 may be omitted.

[0274] A semiconductor layer 410 is provided on the buffer layer 406. The semiconductor layer 410 may be made of or include an oxide semiconductor material or polysilicon.

[0275] A gate insulating layer 420 including an insulating material such as an inorganic insulating material such as silicon oxide (SiO x (where 0 < x ≤ 2)) or silicon nitride (SiN x (where 0 < x ≤ 2)) is provided on the semiconductor layer 410.

[0276] A gate electrode 430 made of a conductive material such as metal is provided above the gate insulating layer 420 corresponding to the center of the semiconductor layer 410. A interlayer insulating layer 440 including an insulating material such as an inorganic insulating material such as SiO x (where 0 < x ≤ 2)) or SiN x (where 0 < x ≤ 2)) or an organic insulating material such as benzocyclobutene or photoacrylic is provided on the gate electrode 430.

[0277] The interlayer insulating layer 440 has a first semiconductor layer contact hole 442 and a second semiconductor layer contact hole 444 that expose a portion of the surface of the semiconductor layer 410 that is closer to the opposite end than the center or do not cover a portion of the surface of the semiconductor layer 410 that is closer to the opposite end than the center. The first semiconductor layer contact hole 442 and the second semiconductor layer contact hole 444 are provided on opposite sides of the gate electrode 430 and are spaced apart from the gate electrode 430.

[0278] On the interlayer insulating layer 440, a source electrode 452 and a drain electrode 454 made of a conductive material such as metal or including a conductive material such as metal are provided. The source electrode 452 and the drain electrode 454 are spaced apart from each other with respect to the gate electrode 430. The source electrode 452 and the drain electrode 454 are in contact with both sides of the semiconductor layer 410 through a first semiconductor layer contact hole 442 and a second semiconductor layer contact hole 444, respectively.

[0279] The semiconductor layer 410, the gate electrode 430, the source electrode 452, and the drain electrode 454 constitute a thin film transistor Tr serving as a driving element.

[0280] Although not shown in Figure 12 , gate lines GL and data lines DL that cross each other to define the pixel region P, and switching elements Ts connected to the gate lines GL and the data lines DL, may also be formed in the pixel region P. The switching element Ts is connected to the thin film transistor Tr serving as a driving element. In addition, a power line PL is spaced apart in parallel from the gate line GL or the data line DL, and the thin film transistor Tr may further include a storage capacitor Cst configured to keep the voltage of the gate electrode 430 constant for one frame.

[0281] Above the entire first substrate 402, a passivation layer 460 is provided on the source electrode 452 and the drain electrode 454 and covers the thin film transistor Tr. The passivation layer 460 has a drain contact hole 462 that exposes the drain electrode 454 of the thin film transistor Tr or does not cover the drain electrode 454 of the thin film transistor Tr.

[0282] The OLED D is positioned on the passivation layer 460. The OLED D includes a first electrode 510 connected to the drain electrode 454 of the thin film transistor Tr, a second electrode 520 facing the first electrode 510, and a light emitting layer 530 provided between the first electrode 510 and the second electrode 520.

[0283] The first electrode 510 formed for each pixel region RP, GP, or BP may be an anode and may include a conductive material having a relatively high work function value. Alternatively, a reflective electrode or a reflective layer may be provided under the first electrode 510. For example, the reflective electrode or the reflective layer may include, but is not limited to, Ag or an APC alloy.

[0284] On the passivation layer 460, a bank layer 464 is provided to cover the edge of the first electrode 510. The bank layer 464 exposes the center of the first electrode 510 corresponding to each of the red pixel region RP, the green pixel region GP, and the blue pixel region BP or does not cover the center of the first electrode 510 corresponding to each of the red pixel RP, the green pixel GP, and the blue pixel BP. In some embodiments, the bank layer 464 may be omitted.

[0285] A light-emitting layer 530 including a plurality of light-emitting units may be disposed on a first electrode 510. As Figure 13 and Figure 14 shown, the light-emitting layer 530 may include a plurality of light-emitting units 600, 700, 700A, and 800, and at least one charge generation layer 680 and 780. Each of the light-emitting units 600, 700, 700A, and 800 includes at least one light-emitting material layer and may further include an HIL, an HTL, an EBL, an HBL, an ETL, and / or an EIL.

[0286] A second electrode 520 may be disposed on a first substrate 402 on which the light-emitting layer 530 may be disposed. The second electrode 520 may be disposed over the entire display area, may include a conductive material having a relatively low work function value compared to the first electrode 510, and may be a cathode. Since the light emitted from the light-emitting layer 530 in the organic light-emitting display device 400 according to the second embodiment of the present disclosure is incident on the color filter layer 480 through the second electrode 520, the second electrode 520 has a thin thickness such that light can be transmitted therethrough.

[0287] The color filter layer 480 is disposed on the OLED D and includes a red color filter pattern 482, a green color filter pattern 484, and a blue color filter pattern 486 that are respectively disposed corresponding to a red pixel region RP, a green pixel region GP, and a blue pixel region BP. Although not shown in Figure 12 , the color filter layer 480 may be attached to the OLED D through an adhesive layer. Alternatively, the color filter layer 480 may be directly disposed on the OLED D.

[0288] In addition, a encapsulation film 470 may be disposed on the second electrode 520 to prevent or reduce the infiltration of external moisture into the OLED D. The encapsulation film 470 may have, but is not limited to, a laminated structure including a first inorganic insulating film, an organic insulating film, and a second inorganic insulating film ( Figure 2 170 in). In addition, a polarizing plate may be attached to the second substrate 404 to reduce the reflection of external light. For example, the polarizing plate may be a circular polarizing plate.

[0289] In Figure 12 , the light emitted from the OLED D passes through the second electrode 520 and the color filter layer 480 is disposed on the OLED D. In this case, the organic light-emitting display device 400 may be a top-emitting type. Alternatively, when the organic light-emitting display device 400 is a bottom-emitting type, the light emitted from the OLED D passes through the first electrode 510 and the color filter layer 480 may be disposed between the OLED D and the first substrate 402.

[0290] In addition, a color conversion layer may be formed or disposed between the OLED D and the color filter layer 480. The color conversion layer may include a red conversion layer, a green conversion layer, and a blue conversion layer that are respectively provided corresponding to the respective pixel regions (RP, GP, and BP) to convert white (W) light into red light, green light, and blue light, respectively. Alternatively, the organic light emitting display device 400 may include a color conversion layer instead of the color filter layer 480.

[0291] As described above, the white (W) light emitted from the OLED D passes through the red color filter pattern 482, the green color filter pattern 484, and the blue color filter pattern 486 that are respectively provided corresponding to the red pixel region RP, the green pixel region GP, and the blue pixel region BP, so that red light, green light, and blue light are displayed in the red pixel region RP, the green pixel region GP, and the blue pixel region BP.

[0292] The OLED that can be applied to the organic light emitting display device will be described in more detail. Figure 13 A schematic cross-sectional view of an organic light emitting diode having a tandem structure with two light emitting portions is shown.

[0293] As Figure 13 As shown, the organic light emitting display device D4 (OLED D4) according to an embodiment of the present disclosure includes a first electrode 510 and a second electrode 520 facing each other, and a light emitting layer 530 disposed between the first electrode 510 and the second electrode 520. The light emitting layer 530 includes a first light emitting portion 600 disposed between the first electrode 510 and the second electrode 520, a second light emitting portion 700 disposed between the first light emitting portion 600 and the second electrode 520, and a charge generation layer (CGL) 680 disposed between the first light emitting portion 600 and the second light emitting portion 700.

[0294] One of the first light emitting portion 600 and the second light emitting portion 700 emits blue light, and the other of the first light emitting portion 600 and the second light emitting portion 700 emits red to green light, so that the OLED D4 can achieve white (W) light emission. At least one exciton generation layer may be disposed adjacent to the blue light emitting material layer in the first light emitting portion 600 and the second light emitting portion 700. Hereinafter, the OLED D4 in which the EML1 640 emits blue light and the EML2 740 emits red to green light will be described in detail.

[0295] The first electrode 510 may be an anode and may include a conductive material having a relatively high work function value, such as a TCO. For example, the first electrode 510 may include, but is not limited to, ITO, IZO, ITZO, SnO, ZnO, ICO, AZO, etc. The second electrode 520 may be a cathode and may include a conductive material having a relatively low work function value. For example, the second electrode 520 may include, but is not limited to, a highly reflective material such as Al, Mg, Ca, Ag, their alloys, and / or their combinations, such as Al-Mg.

[0296] The first light-emitting unit 600 includes a first EML (EML1) 640, and an exciton generation layer (EGL) 650 disposed between the first electrode 510 and the EML1 640, such as between a first hole transport layer (HTL1) 620 or a first electron blocking layer (EBL1) 630 and the EML1 640. The first light-emitting unit 600 may further include at least one of a hole injection layer (HIL) 610 disposed between the first electrode 510 and the EML1 640, an HTL1 620 disposed between the HIL 610 and the EML1 640, and a first electron transport layer (ETL1) 670 disposed between the EML1 640 and the CGL 680. Alternatively or additionally, the first light-emitting unit 600 may further include an EBL1 630 disposed between the HTL1 620 and the EML1 640 and / or a first hole blocking layer (HBL1) 660 disposed between the EML1 640 and the ETL1 670.

[0297] The second light-emitting unit 700 includes a second EML (EML2) 740. The second light-emitting unit 700 may further include at least one of a second hole transport layer (HTL2) 720 disposed between the CGL 680 and the EML2 740, a second electron transport layer (ETL2) 770 disposed between the second electrode 520 and the EML2 740, and an electron injection layer (EIL) 780 disposed between the second electrode 520 and the ETL2 770. Alternatively or additionally, the second light-emitting unit 700 may further include a second electron blocking layer (EBL2) 730 disposed between the HTL2 720 and the EML2 740 and / or a second hole blocking layer (HBL2) 760 disposed between the EML2 740 and the ETL2 770.

[0298] The HIL 610 is disposed between the first electrode 510 and the HTL1 620 and improves the interfacial characteristics between the inorganic first electrode 510 and the organic HTL1 620. In one exemplary embodiment, the hole injection material in the HIL 610 may include, but is not limited to, MTDATA, NATA, 1T-NATA, 2T-NATA, CuPc, TCTA, NPB (NPD), DNDPT, HAT-CN, F4-TCNQ, F6-TCNNQ, TDAPB, PEDOT / PSS, N-(biphenyl-4-yl)-9,9-dimethyl-N-(4-(9-phenyl-9H-carbazol-3-yl)phenyl)-9H-fluoren-2-amine, NPNPB, and / or combinations thereof. In another embodiment, the HIL 610 may comprise a hole injection host of a hole transport material and a hole injection dopant of a hole injection material. In certain embodiments, the HIL 610 may be omitted in accordance with the OLED D4 characteristics.

[0299] In one embodiment, the hole transport material in each of the HTL1 620 and the HTL2 720 may independently include, but is not limited to, TPD, NPB (NPD), DNTPD, CBP, poly-TPD, TFB, TAPC, DCDPA, N-(biphenyl-4-yl)-9,9-dimethyl-N-(4-(9-phenyl-9H-carbazol-3-yl)phenyl)-9H-fluoren-2-amine, N-(biphenyl-4-yl)-N-(4-(9-phenyl-9H-carbazol-3-yl)phenyl)biphenyl-4-amine, N-([1,1'-biphenyl]-4-yl)-9,9-dimethyl-N-(4-(9-phenyl-9H-carbazol-3-yl)phenyl)-9H-fluoren-2-amine, and / or combinations thereof.

[0300] The ETL1 670 and the ETL2 770 each promote electron transport in each of the first light-emitting unit 600 and the second light-emitting unit 700. As an example, the electron transport material in each of the ETL1 670 and the ETL2 770 may independently include at least one of the following: compounds containing

[0301] diazole, Compounds of oxazole, compounds containing benzothiazole, compounds containing benzimidazole, and compounds containing triazine. For example, the electron transport materials in ETL1 670 and ETL2 770 can each independently include, but are not limited to, Alq3, PBD, spiro-PBD, Liq, TPBi, BAlq, Bphen, NBphen, BCP, 2-phenyl-9-(3-(2-phenyl-1,10-phenanthrolin-9-yl)phenyl)-1,10-phenanthroline, TAZ, NTAZ, TpPyPB, TmPPPyTz, PFNBr, TPQ, TSPO1, ZADN, and / or combinations thereof.

[0302] EIL 780 is disposed between the second electrode 520 and ETL2 770 and can improve the physical properties of the second electrode 520, and thus can increase the lifespan of OLED D4. In one embodiment, the electron injection material in EIL 780 can include, but is not limited to, alkali metal halides or alkaline earth metal halides such as LiF, CsF, NaF, BaF2, etc., and / or organometallic compounds such as Liq, lithium benzoate, sodium stearate, etc.

[0303] The electron blocking materials in EBL1 630 and EBL2 730 can each independently include, but are not limited to, TCTA, tris[4-(diethylamino)phenyl]amine, N-(biphenyl-4-yl)-9,9-dimethyl-N-(4-(9-phenyl-9H-carbazol-3-yl)phenyl)-9H-fluorene-2-amine, TAPC, MTDATA, mCP, mCBP, CuPc, DNTPD, TDAPB, DCDPA, 2,8-bis(9-phenyl-9H-carbazol-3-yl)dibenzothiophene, and / or combinations thereof. In another embodiment, the electron blocking materials in EBL1 630 and EBL2 730 can independently include carbazole-containing organic compounds having the structures of Chemical Formula 1 to Chemical Formula 4.

[0304] The hole blocking materials in HBL1 660 and HBL2 760 can each independently include at least one of the following: containing Compounds of oxadiazole, compounds containing triazole, compounds containing phenanthroline, containing benzo Compounds of oxazole, compounds containing benzothiazole, compounds containing benzimidazole, and compounds containing triazine. For example, the hole blocking materials in HBL1 660 and HBL2 760 can each independently include, but are not limited to, BCP, BAlq, Alq3, PBD, spiro-PBD, Liq, B3PYMPM, DPEPO, 9-(6-(9H-carbazol-9-yl)pyridin-3-yl)-9H-3,9'-bicarbazole, TSPO1, and / or combinations thereof. In another embodiment, the hole blocking materials in HBL1 660 and HBL2 760 can independently include organic compounds having the structures of Chemical Formula 7 and Chemical Formula 10.

[0305] CGL 680 is disposed between the first light emitting portion 600 and the second light emitting portion 700. CGL 680 includes an N-type CGL (N-CGL) 685 disposed adjacent to the first light emitting portion 600 and a P-type CGL (P-CGL) 690 disposed adjacent to the second light emitting portion 700. N-CGL 685 injects electrons into the EML1 640 of the first light emitting portion 600, and P-CGL 690 injects holes into the EML2 740 of the second light emitting portion 700.

[0306] N-CGL 685 can be an organic layer doped with an alkali metal (such as Li, Na, K, and Cs) and / or an alkaline earth metal (such as Mg, Sr, Ba, and Ra). For example, the host in N-CGL 685 can include, but is not limited to, Bphen and MTDATA. The content of the alkali metal or alkaline earth metal in N-CGL 685 can be, but is not limited to, about 0.01 wt% to about 30 wt%.

[0307] P-CGL 690 can include, but is not limited to, inorganic materials selected from tungsten oxide (WO x ), molybdenum oxide (MoO x ), beryllium oxide (Be2O3), vanadium pentoxide (V2O5), and / or combinations thereof; and / or organic materials selected from NPD, DNTPD, HAT-CN, F4-TCNQ, F6-TCNNQ, TPD, N,N,N',N'-tetranaphthyl-benzidine (TNB), TCTA, N,N'-dioctyl-3,4,9,10-perylene diimide (PTCDI-C8), and / or combinations thereof.

[0308] EML1 640 can be a blue EML. In this case, EML1 640 can be a blue EML, sky blue EML, or dark blue EML. EML1 640 includes a first host 642, a second host 644, and a light emitter 646. The materials and contents of the first host 642, the second host 644, and the light emitter 646 can be the same as those referred to in Figures 3 to 5The corresponding materials and contents are the same.

[0309] EGL 650 may include a first compound 652 of a P-type exciton-generating compound and a second compound 654 of an N-type exciton-generating compound. The materials and contents of the first compound 652 and the second compound 654 in EGL 650 may be the same as the corresponding materials and contents with reference to Figures 3 to 5 In another embodiment, EGL 650 may be disposed between EML1 640 and HBL1 660 ( Figure 4 ). In another embodiment, EGL 650 may include a first exciton-generating layer disposed between EBL1 630 and EML1 640 and a second exciton-generating layer disposed between EML1 640 and HBL1 660 ( Figure 5 ).

[0310] EML2 740 may include a lower light-emitting material layer (lower EML, first layer) 740A disposed between EBL2 730 and HBL2 760 and an upper light-emitting material layer (upper EML, second layer) 740B disposed between the lower EML 740A and HBL2 760. One of the first layer 740A and the second layer 740B may emit red light, and the other of the first layer 740A and the second layer 740B may emit green light. Hereinafter, EML2 740 in which the first layer 740A emits red light and the second layer 740B emits green light will be described in detail.

[0311] The first layer 740A may include a red host and a red dopant (luminescent body). For example, the red host may include a bipolar red host, or include a P-type red host and an N-type red host.

[0312] For example, the P-type red host may include, but is not limited to, an organic compound containing bi-carbazole, an organic compound containing an arylamine or heteroarylamine having at least one fused aromatic and / or fused heteroaromatic moiety, and / or an organic compound containing an arylamine or heteroarylamine having a spirofluorene moiety. As an example, the N-type red host may include, but is not limited to, an organic compound containing an azine, an organic compound containing a benzimidazole, and / or an organic compound containing a quinazoline.

[0313] For example, the red host may include, but is not limited to, mCP-CN, CBP, mCBP, mCP, DPEPO, 2,8-bis(diphenylphosphoryl)dibenzothiophene (PPT), 1,3,5-tris[(3-pyridinyl)-benz-3-yl]benzene (TmPyPB), 2,6-bis(9H-carbazol-9-yl)pyridine (PYD-2Cz), 2,8-bis(9H-carbazol-9-yl)dibenzothiophene (DCzDBT), 3',5'-bis(carbazol-9-yl)-[1,1'-biphenyl]-3,5-dicarbonitrile (DCzTPA), 4'-(9H-carbazol-9-yl)biphenyl-3,5-dicarbonitrile (pCzB-2CN), 3'-(9H-carbazol-9-yl)biphenyl-3,5-dicarbonitrile (mCzB-2CN), TSPO1, 9-(9-phenyl-9H-carbazol-6-yl)-9H-carbazole (CCP), 4-(3-(triphenylene-2-yl)phenyl)dibenzothiophene, 9-(4-(9H-carbazol-9-yl)phenyl)-9H-3,9'-bicarbazole, 9-(3-(9H-carbazol-9-yl)phenyl)-9H-3,9'-bicarbazole, 9-(6-(9H-carbazol-9-yl)pyridin-3-yl)-9H-3,9'-bicarbazole, 9,9'-diphenyl-9H,9'H-3,3'-bicarbazole (BCzPh), 1,3,5-tris(carbazol-9-yl)benzene (TCP), TCTA, 4,4'-bis(carbazol-9-yl)-2,2'-dimethylbiphenyl (CDBP), (2,7-bis(carbazol-9-yl)-9,9-dimethylfluorene (DMFL-CBP), 2,2',7,7'-tetrakis(carbazol-9-yl)-9,9-spirobifluorene (spiro-CBP), 3,6-bis(carbazol-9-yl)-9-(2-ethylhexyl)-9H-carbazole (TCz1), and / or combinations thereof.

[0314] The red dopant may include at least one of a red phosphorescent material, a red fluorescent material, and a red delayed fluorescent material. For example, the red dopant may include, but is not limited to, bis[2-(4,6-dimethyl)phenylquinoline)](2,2,6,6-tetramethylheptane-3,5-dionato)iridium(III), bis[2-(4-n-hexylphenyl)quinoline](acetylacetonate)iridium(III) (Hex-Ir(phq)2(acac)), tris[2-(4-n-hexylphenyl)quinoline]iridium(III) (Hex-Ir(phq)3), tris[2-phenyl-4-methylquinoline]iridium(III) (Ir(Mphq)3), bis(2-phenylquinoline)(2,2,6,6-tetramethylheptene-3,5-dionato)iridium(III) (Ir(dpm)PQ2), bis(phenylisoquinoline)(2,2,6,6-tetramethylheptene-3,5-dionato)iridium(III) (Ir(dpm)(piq)2), bis(1-phenylisoquinoline)(acetylacetonate)iridium(III) (Ir(piq)2(acac)), bis[(4-n-hexylphenyl)isoquinoline](acetylacetonate)iridium(III) (Hex-Ir(piq)2(acac)), tris[2-(4-n-hexylphenyl)quinoline]iridium(III) (Hex-Ir(piq)3), tris(2-(3-methylphenyl)-7-methyl-quinoline)iridium (Ir(dmpq)3), bis[2-(2-methylphenyl)-7-methyl-quinoline](acetylacetonate)iridium(III) (Ir(dmpq)2(acac)), bis[2-(3,5-dimethylphenyl)-4-methyl-quinoline](acetylacetonate)iridium(III) (Ir(mphmq)2(acac)), tris(dibenzoylmethane)mono(1,10-phenanthroline)europium(III) (Eu(dbm)3(phen)), and / or combinations thereof.

[0315] As an example, the content of the red host in the first layer 740A may be from about 50 wt% to about 99 wt%, such as from about 60 wt% to about 99 wt% or from about 80 wt% to about 95 wt%, and the content of the red dopant in the first layer 740A may be from about 1 wt% to about 50 wt%, such as from about 1 wt% to about 40 wt% or from about 5 wt% to about 20 wt%, but is not limited thereto. When the first layer 740A contains both a P-type red host and an N-type red host, the P-type red host and the N-type red host may be mixed at a weight ratio of about 4:1 to about 1:4, such as about 3:1 to about 1:3, but is not limited thereto.

[0316] The second layer 740B may include a green host and a green dopant (luminescent body). For example, the green host may include a bipolar green host, or include a P-type green host and an N-type green host. The green host may be the same as the above red host.

[0317] The green dopant may include at least one of a green phosphorescent material, a green fluorescent material, and a green delayed fluorescent material. In one embodiment, the green dopant may include, but is not limited to, [bis(2-phenylpyridine)](pyridin-2-ylbenzofuran[2,3-b]pyridine)iridium, tris(2-phenylpyridine)iridium(III) (Ir(ppy)3), fac-tris(2-phenylpyridine)iridium(III) (fac-Ir(ppy)3), bis(2-phenylpyridine)(acetylacetonate)iridium(III) (Ir(ppy)2(acac)), tris[2-(p-tolyl)pyridine]iridium(III) (Ir(mppy)3), bis(2-(naphthalen-2-yl)pyridine)(acetylacetonate)iridium(III) (Ir(npy)2acac), tris(2-phenyl-3-methyl-pyridine)iridium (Ir(3mppy)3), fac-tris(2-(3-p-xylenyl)phenyl)pyridineiridium(III) (TEG), and / or combinations thereof.

[0318] In another embodiment, the green dopant having delayed fluorescence properties may include, but are not limited to, 10-(4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-9,9-dimethyl-9,10-dihydroacridine (DMAC-TRZ), 10,10'-(4,4'-sulfonylbis(4,1-phenylene))bis(9,9-dimethyl-9,10-dihydroacridine (DMAC-DPS), 10-phenyl-10H,10'H-spiro[acridine-9,9'-anthracene]-10'-one (ACRSA), 3,6-dibenzoyl-4,5-bis(1-methyl-9-phenyl-9H-carbazol-3-yl)-2-ethynylbenzonitrile (Cz-VPN), 9,9',9”-(5-(4,6-diphenyl-1,3,5-triazin-2-yl)benzene-1,2,3-triyl)tris(9H-carbazole) (TcZTrz), 9,9'-(5-(4,6-diphenyl-1,3,5-triazin-2-yl)-1,3-phenylene)bis(9H-carbazole) (DcZTrz), 9,9',9”,9”'-((6-phenyl-1,3,5-triazine-2,4-diyl)bis(benzene-5,3,1-triyl))tetrakis(9H-carbazole) (DDczTrz), bis(4-(9H-3,9'-bicarbazol-9-yl)phenyl)methanone (CC2BP), 9'-[4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl]-3,3”,6,6”-tetraphenyl-9,3':6',9”-tri-9H-carbazole (BDPCC-TPTA), 9'-[4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl]-9,3':,6',9”-tri-9H-carbazole (BCC-TPTA), 9,9'-(4,4'-sulfonylbis(4,1-phenylene))bis(3,6-dimethoxy-9H-carbazole) (DMOC-DPS), 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-phen Phenothiazine (Phen-TRZ), 9-(4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-9H-carbazole (Cab-Ph-TRZ), 1,2,3,5-tetrakis(3,6-carbazol-9-yl)-4,6-dicyanobenzene (4CzIPN), 2,3,4,6-tetrakis(9H-carbazol-9-yl)-5-fluorobenzonitrile (4CZFCN), 4,5-bis(9H-carbazol-9-yl)phthalonitrile (2CzPN), 10-(4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-10H-spiro[acridine-9,9'-xanthene], 10-(4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-10H-spiro[acridine-9,9'-fluorene] (SpiroAC-TRZ), and / or combinations thereof.

[0319] As an example, the content of the green host in the second layer 740B can be from about 50 wt% to about 99 wt%, such as from about 60 wt% to about 99 wt% or from about 80 wt% to about 95 wt%, and the content of the green dopant in the second layer 740B can be from about 1 wt% to about 50 wt%, such as from about 1 wt% to about 40 wt% or from about 5 wt% to about 20 wt%, but not limited thereto. When the second layer 740B contains a P-type green host and an N-type green host, the P-type green host and the N-type green host can be mixed at a weight ratio of about 4:1 to about 1:4, such as about 3:1 to about 1:3, but not limited thereto.

[0320] Optionally, the EML2 740 can further include a third layer ( Figure 14 740C in

[0321] The OLED D4 according to this embodiment has a tandem structure and includes an EML1 640 containing a second host 644 having delayed fluorescence characteristics and at least one EGL 650 disposed adjacent to the EML 1 640 for generating an exciplex. The driving voltage of the OLED D4 can be reduced, and the luminous lifetime of the OLED D4 can be improved.

[0322] The OLED can have three or more light-emitting portions to form a tandem structure. Figure 14 FIG. shows a schematic cross-sectional view of an organic light-emitting diode according to another embodiment of the present disclosure.

[0323] As Figure 14As shown, the OLED D5 includes a first electrode 510 and a second electrode 520 facing each other, and a light-emitting layer 530A disposed between the first electrode 510 and the second electrode 520. The light-emitting layer 530A includes a first light-emitting portion 600 disposed between the first electrode 510 and the second electrode 520, a second light-emitting portion 700A disposed between the first light-emitting portion 600 and the second electrode 520, a third light-emitting portion 800 disposed between the second light-emitting portion 700A and the second electrode 520, a first charge generation layer (CGL1) 680 disposed between the first light-emitting portion 600 and the second light-emitting portion 700A, and a second charge generation layer (CGL2) 780 disposed between the second light-emitting portion 700A and the third light-emitting portion 800.

[0324] In one embodiment, at least one of EML1 640, EML2 740', and EML3 840 may emit blue light, and another one of EML1 640, EML2 740', and EML3 840 may emit red-to-green light, such that the OLED D5 can achieve white (W) light emission. In addition, at least one exciton generation layer may be disposed adjacent to the blue light-emitting material layer among the first light-emitting portion 600, the second light-emitting portion 700A, and the third light-emitting portion 800. Hereinafter, the OLED D5 in which the first light-emitting portion 600 and the third light-emitting portion 800 each emit blue light, and the second light-emitting portion 700A emits red-to-green light will be described in detail.

[0325] The first light-emitting portion 600 includes a first light-emitting material layer (EML1) 640, and an exciton generation layer (lower exciton generation layer, L-EGL) 650 disposed between the first electrode 510 and EML1 640, for example, between a first hole transport layer (HTL1) 620 or a first electron blocking layer (EBL1) 630 and EML1 640. The first light-emitting portion 600 may further include at least one of a hole injection layer (HIL) 610 disposed between the first electrode 510 and EML1 640, an HTL1 620 disposed between HIL 610 and EML1 640, and a first electron transport layer (ETL1) 670 disposed between EML1 640 and CGL1 680. Alternatively or additionally, the first light-emitting portion 600 may further include an EBL1 630 disposed between HTL1 620 and EML1 640 and / or a first hole blocking layer (HBL1) 660 disposed between EML1 640 and ETL1 670.

[0326] The second light-emitting part 700A includes a second light-emitting material layer (EML2) 740'. The second light-emitting part 700A may further include at least one of a second hole transport layer (HTL2) 720 disposed between the CGL1 680 and the EML2 740' and a second electron transport layer (ETL2) 770 disposed between the EML2 740' and the CGL2 780. Alternatively or additionally, the second light-emitting part 700A may further include a second electron blocking layer (EBL2) 730 disposed between the HTL2 720 and the EML2 740' and / or a second hole blocking layer (HBL2) 760 disposed between the EML2 740' and the ETL2 770.

[0327] The third light-emitting part 800 includes a third light-emitting material layer (EML3) 840, and an exciton generation layer (upper exciton generation layer, U-EGL) 850 disposed between the CGL2 780 and the EML3 840, such as between a third hole transport layer (HTL3) 820 or a third electron blocking layer (EBL3) 830 and the EML3 840. The third light-emitting part 800 may further include at least one of an HTL3 820 disposed between the CGL2 780 and the EML3 840, a third electron transport layer (ETL3) 870 disposed between the second electrode 520 and the EML3 840, and an electron injection layer (EIL) 880 disposed between the second electrode 520 and the ETL3 870. Alternatively or additionally, the third light-emitting part 800 may further include an EBL3 830 disposed between the HTL3 820 and the EML3 840 and / or a third hole blocking layer (HBL3) 860 disposed between the EML3 840 and the ETL3 870.

[0328] The CGL1 680 is disposed between the first light-emitting part 600 and the second light-emitting part 700A, and the CGL2 780 is disposed between the second light-emitting part 700A and the third light-emitting part 800. The CGL1 680 includes a first N-type charge generation layer (N-CGL1) 685 disposed adjacent to the first light-emitting part 600 and a first P-type charge generation layer (P-CGL1) 690 disposed adjacent to the second light-emitting part 700A. The CGL2 780 includes a second N-type charge generation layer (N-CGL2) 785 disposed adjacent to the second light-emitting part 700A and a second P-type charge generation layer (P-CGL2) 790 disposed adjacent to the third light-emitting part 800. The N-CGL1 685 and the N-CGL2 785 each inject electrons into the EML1 640 of the first light-emitting part 600 and the EML2 740' of the second light-emitting part 700A, and the P-CGL1 690 and the P-CGL2 790 each inject holes into the EML2 740' of the second light-emitting part 700A and the EML3 840 of the third light-emitting part 800.

[0329] The materials included in HIL 610, HTL1 to HTL3 620, 720, and 820, EBL1 to EBL3 630, 730, and 830, HBL1 to HBL3 660, 760, and 860, ETL1 to ETL3 670, 770, and 870, EIL 880, CGL1 680, and CGL2 780 may be the same as the materials with reference to Figure 3 and Figure 13 the reference.

[0330] Each of EML1 640 and EML3 840 may independently be a blue EML. In this case, each of EML1 640 and EML3 840 may independently be a blue EML, a sky blue EML, or a dark blue EML. Each of EML1 640 and EML3 840 may independently include a first host 642 or 842, a second host 644 or 844, and a light emitter 646 or 846 that emits final light. The materials and contents of the first host 642 or 842, the second host 644 or 844, and the light emitter 646 or 846 in each of EML1 640 and EML3 840 may be the same as the corresponding materials and contents with reference to Figures 3 to 5 the reference.

[0331] The first host 642 in EML 1 640 may be the same as or different from the first host 842 in EML3 840. The second host 644 in EML1 640 may be the same as or different from the second host 844 in EML3 840. The light emitter 646 in EML 640 may be the same as or different from the light emitter 846 in EML3 840.

[0332] Each of L-EGL 650 and U-EGL 850 may independently include a first compound 652 and 852 of a P-type exciton generating compound and a second compound 654 and 854 of an N-type exciton generating compound. The first compound 652 in L-EGL 650 may be the same as or different from the first compound 852 in U-EGL 850. The second compound 654 in L-EGL 650 may be the same as or different from the second compound 854 in U-EGL 850. The materials and contents of the first compound 652 and 852 and the second compound 654 and 854 in each of L-EGL 650 and U-EGL 850 may be the same as the corresponding materials and contents with reference to Figures 3 to 5 the reference.

[0333] In another embodiment, L-EGL 650 may be disposed between EML1 640 and HBL1 660, and / or U-EGL 850 may be disposed between EML3 840 and HBL3 860 (Figure 4 )。In another embodiment, L-EGL650 may include a first exciton generation layer disposed between EBL1 630 and EML1 640 and a second exciton generation layer disposed between EML1 640 and HBL1 660, and / or U-EGL850 may include a first exciton generation layer disposed between EBL3 830 and EML3 840 and a second exciton generation layer disposed between EML3 840 and HBL3 860( Figure 5 ).

[0334] EML2 740' may include a lower light-emitting material layer (first layer) 740A disposed between EBL2 730 and HBL2 760, an upper light-emitting material layer (second layer) 740B disposed between the first layer 740A and HBL2 760, and an intermediate light-emitting material layer (third layer) 740C disposed between the first layer 740A and the second layer 740B. One of the first layer 740A and the second layer 740B may emit red light, and the other of the first layer 740A and the second layer 740B may emit green light. Hereinafter, EML2 740' in which the first layer 740A emits red light and the second layer 740B emits green light will be described in detail.

[0335] The first layer 740A may include a red host and a red dopant. The materials and contents of the red host and the red dopant in the first layer 740A may be the same as those with reference to Figure 13 . The second layer 740B may include a green host and a green dopant. The materials and contents of the green host and the green dopant in the second layer 740B may be the same as those with reference to Figure 13 .

[0336] The third layer 740C may be a yellow-green EML. The third layer 740C may include a yellow-green host and a yellow-green dopant (luminescent body). For example, the yellow-green host may include a bipolar yellow-green host, or include a P-type yellow-green host and an N-type yellow-green host. For example, the yellow-green host may be the same as the red host and / or the green host with reference to Figure 13 .

[0337] The yellow-green dopant may include at least one of a yellow-green phosphorescent material, a yellow-green fluorescent material, and a yellow-green delayed fluorescent material. For example, the yellow-green dopant may include, but is not limited to, 5,6,11,12-tetraphenylnaphthalene (rubrene), 2,8-di-tert-butyl-5,11-bis(4-tert-butylphenyl)-6,12-diphenyltetracene (TBRb), bis(2-phenylbenzothiazole)(acetylacetonate)iridium(III) (Ir(BT)2(acac)), bis(2-(9,9-diethyl-fluoren-2-yl)-1-phenyl-1H-benzo[d]imidazole)(acetylacetonate)iridium(III) (Ir(fbi)2(acac)), fac-tris(2-phenylpyridine)(3-(pyridin-2-yl)-2H-chromen-2-one)iridium(III) (fac-Ir(ppy)2Pc), bis(2-(2,4-difluorophenyl)quinoline)(picolinato)iridium(III) (FPQIrpic), bis(4-phenylthieno[3,2-c]pyrido-N,C2')(acetylacetonate)iridium(III) (PO-01), and / or combinations thereof. In certain embodiments, the third layer 740C may be omitted.

[0338] When the third layer 740C includes at least one yellow-green host, the content of the yellow-green host in the third layer 740C may be from about 50 wt% to about 99 wt%, such as from about 60 wt% to about 99 wt% or from about 80 wt% to about 95 wt%, and the content of the yellow-green dopant in the third layer 740C may be from about 1 wt% to about 50 wt%, such as from about 1 wt% to about 40 wt% or from about 5 wt% to about 20 wt%, but is not limited thereto. When the third layer 740C includes a P-type yellow-green host and an N-type yellow-green host, the P-type yellow-green host and the N-type yellow-green host may be mixed in a weight ratio of from about 4:1 to about 1:4, such as from about 3:1 to about 1:3, but is not limited thereto.

[0339] The OLED D5 according to this embodiment has a tandem structure and includes EML1 640 and / or EML3 840 each containing a second host 644 or 844 having delayed fluorescence characteristics, and at least one EGL 650 and 850 for generating an exciplex disposed adjacent to each of EML1 640 and / or EML3 840. The OLED D5 enables a reduction in its driving voltage, an improvement in its luminous lifetime, and white light emission.

[0340] In Figure 14In the figure, an OLED having three light-emitting portions is shown. If necessary, the organic light-emitting diode may have four or more light-emitting portions. As an example, when the OLED has four light-emitting portions, two light-emitting portions may emit blue light, another light-emitting portion may emit red light, and the remaining light-emitting portion may emit green light, so that the OLED can achieve white (W) light emission.

[0341] Experimental Example 1: Measurement of the emission spectrum and energy levels of compounds

[0342] Measure the absorption (Abs) spectrum and photoluminescence (PL) spectrum of organic compounds that can be used for the exciton generation layer and the light-emitting material layer, as well as the HOMO energy level, LUMO energy level, lowest excited singlet state energy level S1, and lowest excited triplet state energy level T1 based on those spectra. In particular, measure the compound PD25 of Chemical Formula 12 of the phosphorescent material (luminophore) in the light-emitting material layer, the compounds P1-1, P1-7, and P1-18 that can each be used as the first compound in the exciton generation layer or the first host in the light-emitting material layer, the compound N1-1 of Chemical Formula 6 of the second compound in the exciton generation layer, or the following reference compound 1 (Ref.1), and the Abs spectrum, PL spectrum, and energy levels of the compounds N2-1, N2-26 of Chemical Formula 10 of the second host in the light-emitting material layer or the following reference compound 2 (Ref.2).

[0343] Reference compound

[0344]

[0345] The band gap is calculated from the Abs spectrum of each compound (10 -5 M) dissolved in toluene using an ultraviolet-visible (UV-Vis) device. The HOMO energy level and LUMO energy level are measured using cyclic voltammetry (CV). The measurement material is coated on the working electrode (glassy carbon electrode), the electrode is immersed in the electrolyte solution (0.1 M tetrabutylammonium perchlorate), the oxidation potential is measured, and then the HOMO energy level is calculated from the starting curve obtained from the oxidation potential (reference electrode Ag / AgCl, counter electrode Pt wire). The LUMO energy level is calculated from the HOMO energy level obtained by CV measurement and the band gap measured using the UV-Vis device (LUMO energy level = band gap - HOMO energy level).

[0346] The lowest excited singlet state energy level S1 and the lowest excited triplet state energy level T1 of the compound are measured using a photoluminescence (PL) device (measured after a 1 millisecond delay of light excitation gn). The starting wavelength λstart is based on each compound (10 -5The 1st peak in the low-temperature (77 K) fluorescence (Fl) spectrum of (M), and the lowest excited singlet state energy level S1 was calculated by 1240 / λstart (the start wavelength of the Fl spectrum). The start wavelength λstart was based on each compound dissolved in toluene solvent (10 -5 The 1st peak in the low-temperature (77 K) phosphorescence (PL) spectrum of (M), and the lowest excited triplet state energy level T1 was calculated by 1240 / λstart (the start wavelength of the Ph spectrum). ΔE was calculated by S1 - T1 ST . In addition, the maximum photoluminescence wavelength (λ 最大 , nm), the start wavelength of the PL spectrum (λstart PL , nm), and the start wavelength of the Abs spectrum (λstart Abs , nm) of each compound were measured. The measurement results are indicated or shown in Table 1 and Table 2 below and Figures 15 to 17 .

[0347] Table 1: Energy levels of compounds

[0348]

[0349] Table 2: Maximum photoluminescence wavelength and start wavelength of compounds

[0350] Compound λ max (nm) <![CDATA[λ start PL (nm)]]> <![CDATA[λ start Abs. (nm)]]> PD25 461 442 430 P1-1 377 358 - P1-18 378 359 - N1-1 446 380 - Ref.1 412 372 - P1-1:N1-1 469 408 - P1-18:N1-1 466 402 - P1-1:Ref.1 412 375 -

[0351] As indicated in Tables 1 to 2 and Figures 15 to 17 , since exciplexes are generated between compound P1-1 and compound N1-1 and between compound P1-18 and compound N1-1, new photoluminescence spectra were observed at longer wavelengths compared to the photoluminescence wavelengths of compounds P1-1, P1-18, and N1-1. On the contrary, no exciplex was generated between compound P1-1 and reference compound Ref.1, and no new photoluminescence spectrum was observed at longer wavelengths compared to the photoluminescence wavelengths of those compounds.

[0352] Example 1 (EX.1): Fabrication of OLED

[0353] An organic light-emitting diode was fabricated in which an exciton generation layer was introduced between the electron blocking layer and the light-emitting material layer and between the light-emitting material layer and the hole blocking layer. A glass substrate coated with ITO (50 nm) as a thin film was ultrasonically washed with isopropyl alcohol, acetone, and methanol and dried in an oven at 100 °C. The prepared ITO transparent electrode was transferred to a vacuum chamber for depositing the light-emitting layer. Subsequently, the deposition rate was set in the following order / s at about 5×10 -7 Torr to 7×10 -7 Torr, and the light-emitting layer and the cathode were deposited by evaporation from a heated boat:[[]]END]]

[0354] Hole injection layer (HIL, NPB (95 wt%), F4-TCNQ (5 wt%), 10 nm thickness); hole transport layer (HTL, NPB, 50 nm thickness); electron blocking layer (EBL, compound P1-1, 5 nm thickness); first exciton generation layer (EGL1, compound P1-1 (50 wt%), compound N1-1 (50 wt%), 5 nm thickness); light-emitting material layer (EML, compound P1-1 (56 wt%), compound N2-1 (28 wt%), compound PD25 (luminescent material, 16 wt%), 20 nm thickness); second exciton generation layer (EGL2, compound P1-1 (50 wt%), compound N1-1 (50 wt%), 5 nm thickness); hole blocking layer (HBL, compound N2-1, 5 nm thickness); electron transport layer (ETL, 2-phenyl-9-(3-(2-phenyl-1,10-phenanthrolin-9-yl)phenyl)-1,10-phenanthroline, 30 nm thickness); electron injection layer (EIL, LiF, 1 nm thickness); and cathode (Al, 100 nm thickness).

[0355] The fabricated organic light-emitting diode is encapsulated with glass and transferred from the deposition chamber to a drying oven to form a film, and is encapsulated using a UV-cured epoxy resin and a moisture absorbent. The structures of the materials for the hole injection material, hole transport material, and electron transport material are shown below:

[0356]

[0357] Example 2 (EX.2): Fabrication of OLED

[0358] An OLED is fabricated using the same steps and the same materials as in Example 1, except that the second exciton generation layer (EGL2) between the EML and the HBL is not formed and the thickness of the ETL is modified to 35 nm.

[0359] Example 3 (EX.3): Fabrication of OLED

[0360] An OLED is fabricated using the same steps and the same materials as in Example 1, except that the first exciton generation layer (EGL1) between the EBL and the EML is not formed and the thickness of the HTL is modified to 55 nm.

[0361] Example 4 (EX.4): Fabrication of OLED

[0362] An OLED is fabricated using the same steps and the same materials as in Example 1, except that the EBL is not formed and the thickness of the HTL is modified to 55 nm.

[0363] Example 5 (EX.5): Fabrication of OLED

[0364] An OLED was fabricated using the same steps and the same materials as in Example 1, except that the HBL was not formed and the thickness of the ETL was modified to 35 nm.

[0365] Example 6 (EX.6): Fabrication of an OLED

[0366] An OLED was fabricated using the same steps and the same materials as in Example 1, except that the thicknesses of the HTL, EML, and ETL were respectively modified to 45 nm, 30 nm, and 25 nm.

[0367] Example 7 (EX.7): Fabrication of an OLED

[0368] An OLED was fabricated using the same steps and the same materials as in Example 6, except that the second exciton generation layer (EGL2) between the EML and the HBL was not formed and the thickness of the ETL was modified to 30 nm.

[0369] Example 8 (EX.8): Fabrication of an OLED

[0370] An OLED was fabricated using the same steps and the same materials as in Example 6, except that the first exciton generation layer (EGL1) between the EBL and the EML was not formed and the thickness of the HTL was modified to 50 nm.

[0371] Comparative Example 1 (REF.1): Fabrication of an OLED

[0372] An OLED was fabricated using the same steps and the same materials as in Example 1, except that the first exciton generation layer (EGL1) between the EBL and the EML and the second exciton generation layer (EGL2) between the EML and the HBL were not formed, and the thicknesses of the HTL and ETL were respectively modified to 55 nm and 35 nm.

[0373] Comparative Example 2 (REF.2): Fabrication of an OLED

[0374] An OLED was fabricated using the same steps and the same materials as in Example 6, except that the first exciton generation layer (EGL1) between the EBL and the EML and the second exciton generation layer (EGL2) between the EML and the HBL were not formed, and the thicknesses of the HTL and ETL were respectively modified to 50 nm and 30 nm.

[0375] Experimental Example 2: Measurement of the light-emitting characteristics of an OLED

[0376] The light-emitting areas of the OLEDs fabricated in Examples 1 to 8 and Comparative Examples 1 to 2 were 9 mm 2Each OLED is connected to an external power supply, and then the luminescence characteristics of all OLEDs are evaluated using a constant current source (KEITHLEY) and a photometer PR650 at room temperature. In particular, the driving voltage (V, relative value), the external quantum efficiency (EQE, relative value), and the time period from the initial luminance to 95% luminance as the luminescence lifetime (LT 2 95 , %, relative value) are measured at a current density of 5 mA / cm. The measurement results are shown in Table 3 below.

[0377] Table 3: Luminescence characteristics of OLEDs

[0378]

[0379] Example 9 (EX.9): Fabrication of OLED

[0380] An OLED is fabricated using the same steps and the same materials as in Example 1, except that the compound N2-26 of Chemical Formula 10 is used instead of the compound N2-1 as the second host in the EML and the material in the HBL.

[0381] Example 10 (EX.10): Fabrication of OLED

[0382] An OLED is fabricated using the same steps and the same materials as in Example 9, except that the second exciton generation layer (EGL2) between the EML and the HBL is not formed and the thickness of the ETL is modified to 35 nm.

[0383] Example 11 (EX.11): Fabrication of OLED

[0384] An OLED is fabricated using the same steps and the same materials as in Example 9, except that the first exciton generation layer (EGL1) between the EBL and the EML is not formed and the thickness of the HTL is modified to 55 nm.

[0385] Comparative Example 3 (REF.3): Fabrication of OLED

[0386] An OLED is fabricated using the same steps and the same materials as in Example 9, except that the first exciton generation layer (EGL1) between the EBL and the EML and the second exciton generation layer (EGL2) between the EML and the HBL are not formed, and the thicknesses of the HTL and the ETL are each modified to 55 nm and 35 nm, respectively.

[0387] Experimental Example 3: Measurement of luminescence characteristics of OLED

[0388] The luminescence characteristics of the OLEDs fabricated in Examples 9 to 11 and Comparative Example 3 are measured as in Experimental Example 2. The measurement results are shown in Table 4 below.

[0389] Table 4: Luminescence characteristics of OLED

[0390]

[0391] Example 12 (EX.12): Fabrication of OLED

[0392] An OLED was fabricated using the same steps and the same materials as in Example 1, except that the first compound and the second compound in EGL1 and EGL2 were modified to Compound P1-18 (67 wt%) and Compound N1-1 (33 wt%) of Chemical Formula 2.

[0393] Example 13 (EX.13): Fabrication of OLED

[0394] An OLED was fabricated using the same steps and the same materials as in Example 1, except that the first compound and the second compound in EGL1 were modified to Compound P1-18 (67 wt%) and Compound N1-1 (33 wt%) of Chemical Formula 2

[0395] Experimental Example 4: Measurement of luminescence characteristics of OLED

[0396] The luminescence characteristics of each OLED fabricated in Example 1 and Examples 12 to 13 and Comparative Example 1 were measured as in Experimental Example 2. The measurement results are shown in Table 5 below

[0397] Table 5: Luminescence characteristics of OLED

[0398]

[0399] Example 14 (EX.14): Fabrication of OLED

[0400] An OLED was fabricated using the same steps and the same materials as in Example 1, except that Compound P1-7 of Chemical Formula 2 was used instead of Compound P1-1 as the first host in the EML

[0401] Example 15 (EX.15): Fabrication of OLED

[0402] An OLED was fabricated using the same steps and the same materials as in Example 14, except that the second exciton generation layer (EGL2) between the EML and the HBL was not formed and the thickness of the ETL was modified to 35 nm

[0403] Example 16 (EX.16): Fabrication of OLED

[0404] An OLED was fabricated using the same procedure and the same materials as in Example 14, except that the first exciton generation layer (EGL1) between the EBL and the EML was not formed and the thickness of the HTL was modified to 55 nm.

[0405] Comparative Example 4 (REF.4): Fabrication of OLED

[0406] An OLED was fabricated using the same procedure and the same materials as in Example 14, except that the first exciton generation layer (EGL1) between the EBL and the EML and the second exciton generation layer (EGL2) between the EML and the HBL were not formed, and the thicknesses of the HTL and the ETL were modified to 55 nm and 35 nm, respectively.

[0407] Experimental Example 5: Measurement of the light-emitting characteristics of OLEDs

[0408] The light-emitting characteristics of the OLEDs fabricated in Examples 14 to 16 and Comparative Example 4 were measured as in Experimental Example 2. The measurement results are shown in Table 6 below.

[0409] Table 6: Light-emitting characteristics of OLEDs

[0410]

[0411] Comparative Example 5 (REF.5): Fabrication of OLED

[0412] An OLED was fabricated using the same procedure and the same materials as in Example 1, except that Reference Compound Ref.2 was used instead of Compound N2-1 as the second host in the EML and the material in the HBL.

[0413] Experimental Example 6: Measurement of the light-emitting characteristics of OLEDs

[0414] The light-emitting characteristics of the OLEDs fabricated in Example 1 and Comparative Examples 1 and 5 were measured as in Experimental Example 2. The measurement results are shown in Table 7 below.

[0415] Table 7: Light-emitting characteristics of OLEDs

[0416]

[0417] Comparative Example 6 (REF.6): Fabrication of OLED

[0418] An OLED was fabricated using the same procedure and the same materials as in Example 14, except that Compound P1-1 (50 wt%) which cannot generate exciplex and Reference Compound Ref.1 (50 wt%) were used as the materials in the EGL1 and the EGL2.

[0419] Experimental Example 7: Measurement of the light-emitting characteristics of OLEDs

[0420] The light-emitting characteristics of each OLED fabricated in Example 1 and Comparative Examples 1 and 6 were measured as in Experimental Example 2. The measurement results are shown in Table 8 below.

[0421] Table 8: Light-Emitting Characteristics of OLEDs

[0422]

[0423] Comparative Example 7 (REF.7): Fabrication of OLED

[0424] An OLED was fabricated using the same steps and the same materials as in Example 14, except that a compound P1-1 (50 wt%) that cannot form an exciplex and a reference compound Ref.1 (50 wt%) were used as the materials in EGL1 and EGL2, and a reference compound Ref.2 that does not have delayed fluorescence characteristics was used as the second host in the EML.

[0425] Experimental Example 8: Measurement of Light-Emitting Characteristics of OLED

[0426] The light-emitting characteristics of each OLED fabricated in Example 1 and Comparative Examples 1 and 7 were measured as in Experimental Example 2. The measurement results are shown in Table 9 below.

[0427] Table 9: Light-Emitting Characteristics of OLEDs

[0428]

[0429] As indicated in Tables 2 to 9, compared with the OLEDs fabricated in Comparative Examples in which an exciton generation layer is not formed or a non-exciton generation layer composed of a compound that cannot form an exciplex is formed adjacent to an EML having the same thickness, in the OLEDs fabricated in Examples in which an exciton generation layer composed of a compound that can form an exciplex is formed adjacent to an EML having the same thickness, the emission lifetime was significantly improved due to the expansion of the exciton recombination region. Even when the thickness of the EML was reduced, the emission lifetime was maintained at the same level, and the emission efficiency increased instead. An OLED with high efficiency and longer lifetime can be achieved by reducing the amount of expensive phosphorescent materials. In addition, compared with the OLEDs fabricated in Comparative Examples in which a non-delayed fluorescence material is used as the second host in the EML, in the OLEDs fabricated in Examples in which a delayed fluorescence material is used as the second host in the EML, the emission efficiency was maintained at the same level, the driving voltage was significantly reduced, and the emission lifetime was significantly increased.

[0430] It has been determined that an OLED having a reduced or maintained driving voltage, maintaining its luminous efficiency and significantly improving its luminous lifetime can be manufactured by forming at least one exciton generation layer containing a material capable of generating an exciplex, which is disposed adjacent to the light-emitting material layer.

[0431] It will be apparent to those skilled in the art that various modifications and variations can be made in the disclosure without departing from the scope of the disclosure. Accordingly, the disclosure is intended to cover modifications and variations of the disclosure as long as they fall within the scope of the appended claims.

[0432] The various embodiments described above can be combined to provide additional embodiments. If necessary, aspects of the embodiments can be modified to incorporate the concepts in various patents, applications, and publications to provide yet further embodiments.

[0433] Based on the foregoing detailed description, these and other changes can be made to the embodiments. In general, in the appended claims, the terms used should not be construed as limiting the claims to the specific embodiments disclosed in the specification and claims, but should be construed to include all possible embodiments and the full scope of equivalents to which such claims are entitled. Accordingly, the claims are not limited by the disclosure.

Claims

1. An organic light emitting diode, comprising: a first electrode; a second electrode facing the first electrode; and a light-emitting layer disposed between the first electrode and the second electrode, The light-emitting layer comprises: a layer of luminescent material; and a first exciton generating layer disposed between the first electrode and the light emitting material layer or between the light emitting material layer and the second electrode, wherein the first exciton generating layer comprises a first compound and a second compound, The luminescent material layer comprises a first host, a second host and a luminescent body, The first compound and the first host each independently include an organic compound having a structure of the following Chemical Formula 1 or Chemical Formula 3, wherein the second compound comprises an organic compound having a structure of the following Chemical Formula 5, and The second host includes an organic compound having a structure of the following Chemical Formula 7: Chemical formula 1 Chemical formula 3 Wherein, in Chemical Formula 1 and Chemical Formula 3, R 1 To R 5 and R 11 To R 16 are each independently hydrogen, deuterium, halogen, cyano, unsubstituted or substituted C1 to C 20 Alkyl, unsubstituted or substituted C2 to C 20 alkenyl, unsubstituted or substituted C2 to C 20 Alkynyl, unsubstituted or substituted C1 to C 20 Alkoxy, amino, unsubstituted or substituted C1 to C 20 Alkylamino, unsubstituted or substituted C1 to C 20 Alkylsilyl, unsubstituted or substituted C4 to C 30 Cycloalkyl, unsubstituted or substituted C3 to C 30 Heterocycloalkyl, unsubstituted or substituted C6 to C 30 Aryl, unsubstituted or substituted C2 to C 30 heteroaryl, unsubstituted or substituted C7 to C 30 Arylalkyl, unsubstituted or substituted C3 to C 30 heteroarylalkyl, unsubstituted or substituted C6 to C 30 Aryloxy, unsubstituted or substituted C2 to C 30 heteroaryloxy, unsubstituted or substituted C6 to C 30 Arylamino, unsubstituted or substituted C2 to C 30 heteroarylamino, unsubstituted or substituted C6 to C 30 Arylsilyl, unsubstituted or substituted C2 to C 30 heteroarylsilyl, unsubstituted or substituted C1 to C 20 Alkylgermanyl, unsubstituted or substituted C6 to C 30 Arylgermyl, unsubstituted or substituted C2 to C 30 Heteroarylgermyl, unsubstituted or substituted C6 to C 30 triarylmethyl, or unsubstituted or substituted C2 to C 30 triheteroarylmethyl, wherein when a1 is 2, 3, 4 or 5, each R 1 The same or different from each other, when a2 is 2, 3 or 4, each R 2 The same or different from each other, when a3 is 2, 3 or 4, each R 3 The same or different from each other, when a4 is 2 or 3, each R 4 The same or different from each other, when a5 is 2, 3 or 4, each R 5 The same or different from each other, when b1 is 2, 3 or 4, each R 11 The same or different from each other, when b2 is 2, 3 or 4, each R 12 The same or different from each other, when b3 is 2, 3 or 4, each R 13 The same or different from each other, when b4 is 2, 3 or 4, each R 14 The same or different from each other, when b5 is 2, 3 or 4, each R 15 are the same as or different from each other, and when b6 is 2, 3 or 4, each R 16 the same as or different from one another; a1 is 0, 1, 2, 3, 4 or 5; a2, a3, a5, b1, b2, b3, b4, b5 and b6 are each independently 0, 1, 2, 3 or 4; and a4 is 0, 1, 2 or 3, Chemical formula 5 Among them, in chemical formula 5, Z 1 C, Si or Ge; R 21 To R 28 are each independently hydrogen, deuterium, halogen, cyano, unsubstituted or substituted C1 to C 20 Alkyl, unsubstituted or substituted C2 to C 20 alkenyl, unsubstituted or substituted C2 to C 20 Alkynyl, unsubstituted or substituted C1 to C 20 Alkoxy, amino, unsubstituted or substituted C1 to C 20 Alkylamino, unsubstituted or substituted C1 to C 20 Alkylsilyl, unsubstituted or substituted C4 to C 30 Cycloalkyl, unsubstituted or substituted C3 to C 30 Heterocycloalkyl, unsubstituted or substituted C6 to C 30 Aryl, unsubstituted or substituted C2 to C 30 heteroaryl, unsubstituted or substituted C7 to C 30 Arylalkyl, unsubstituted or substituted C3 to C 30 heteroarylalkyl, unsubstituted or substituted C6 to C 30 Aryloxy, unsubstituted or substituted C2 to C 30 heteroaryloxy, unsubstituted or substituted C6 to C 30 Arylamino, unsubstituted or substituted C2 to C 30 heteroarylamino, unsubstituted or substituted C6 to C 30 Arylsilyl, unsubstituted or substituted C2 to C 30 heteroarylsilyl, unsubstituted or substituted C1 to C 20 Alkylgermanyl, unsubstituted or substituted C6 to C 30 Arylgermyl, unsubstituted or substituted C2 to C 30 Heteroarylgermyl, unsubstituted or substituted C6 to C 30 triarylmethyl, or unsubstituted or substituted C2 to C 30 triheteroarylmethyl, wherein when c1 is 2, 3 or 4, each R 21 The same or different from each other, when c2 is 2, 3 or 4, each R 22 The same or different from each other, when c3 is 2, 3 or 4, each R 23 The same or different from each other, when c4 is 2, 3 or 4, each R 24 The same or different from each other, when c5 is 2, 3 or 4, each R 25 The same or different from each other, when c6 is 2, 3, 4 or 5, each R 26 The same or different from each other, when c7 is 2, 3, 4 or 5, each R 27 are the same as or different from each other, and when c8 is 2, 3, 4 or 5, each R 28 the same as or different from one another; c1, c2, c3, c4 and c5 are each independently 0, 1, 2, 3 or 4; and c6, c7 and c8 are each independently 0, 1, 2, 3, 4 or 5, Chemical formula 7 Among them, in chemical formula 7, R 31 To R 33 are each independently hydrogen, deuterium, halogen, cyano, unsubstituted or substituted C1 to C 20 Alkyl, unsubstituted or substituted C2 to C 20 alkenyl, unsubstituted or substituted C2 to C 20 Alkynyl, unsubstituted or substituted C1 to C 20 Alkoxy, amino, unsubstituted or substituted C1 to C 20 Alkylamino, unsubstituted or substituted C1 to C 20 Alkylsilyl, unsubstituted or substituted C4 to C 30 Cycloalkyl, unsubstituted or substituted C3 to C 30 Heterocycloalkyl, unsubstituted or substituted C6 to C 30 Aryl, unsubstituted or substituted C2 to C 30 heteroaryl, unsubstituted or substituted C7 to C 30 Arylalkyl, unsubstituted or substituted C3 to C 30 heteroarylalkyl, unsubstituted or substituted C6 to C 30 Aryloxy, unsubstituted or substituted C2 to C 30 heteroaryloxy, unsubstituted or substituted C6 to C 30 Arylamino, unsubstituted or substituted C2 to C 30 heteroarylamino, unsubstituted or substituted C6 to C 30 Arylsilyl, unsubstituted or substituted C2 to C 30 heteroarylsilyl, unsubstituted or substituted C1 to C 20 Alkylgermanyl, unsubstituted or substituted C6 to C 30 Arylgermyl, unsubstituted or substituted C2 to C 30 Heteroarylgermyl, unsubstituted or substituted C6 to C 30 triarylmethyl, unsubstituted or substituted C2 to C 30 triheteroarylmethyl, or having the structure of the following chemical formula 8, wherein when d1 is 2, 3 or 4, each R 31 are the same as or different from each other, and when d2 is 2, 3 or 4, each R 32 are the same as or different from each other, d1 and d2 are each independently 0, 1, 2, 3 or 4, wherein the polycyclic ring containing boron and oxygen has at least one heteroaryl group having a structure of the following Chemical Formula 9: Chemical formula 8 Among them, in chemical formula 8, Z 2 C, Si or Ge; R 34 To R 36 are each independently unsubstituted or substituted C6 to C 30 Aryl, unsubstituted or substituted C2 to C 30 heteroaryl, unsubstituted or substituted C7 to C 30 Arylalkyl, unsubstituted or substituted C3 to C 30 heteroarylalkyl, unsubstituted or substituted C6 to C 30 aryloxy, or unsubstituted or substituted C2 to C 30 heteroaryloxy; L 1 is a direct bond, an unsubstituted or substituted C6 to C 30 Arylene or unsubstituted or substituted C2 to C 30 Heteroarylene; and The wavy lines indicate the connection locations. Chemical formula 9 Among them, in chemical formula 9, R 41 and R 42 are each independently hydrogen, deuterium, halogen, cyano, unsubstituted or substituted C1 to C 20 Alkyl, unsubstituted or substituted C2 to C 20 alkenyl, unsubstituted or substituted C2 to C 20 Alkynyl, unsubstituted or substituted C1 to C 20 Alkoxy, amino, unsubstituted or substituted C1 to C 20 Alkylamino, unsubstituted or substituted C1 to C 20 Alkylsilyl, unsubstituted or substituted C4 to C 30 Cycloalkyl, unsubstituted or substituted C3 to C 30 Heterocycloalkyl, unsubstituted or substituted C6 to C 30 Aryl, unsubstituted or substituted C2 to C 30 heteroaryl, unsubstituted or substituted C7 to C 30 Arylalkyl, unsubstituted or substituted C3 to C 30 heteroarylalkyl, unsubstituted or substituted C6 to C 30 Aryloxy, unsubstituted or substituted C2 to C 30 heteroaryloxy, unsubstituted or substituted C6 to C 30 Arylamino, unsubstituted or substituted C2 to C 30 heteroarylamino, unsubstituted or substituted C6 to C 30 Arylsilyl, unsubstituted or substituted C2 to C 30 heteroarylsilyl, unsubstituted or substituted C1 to C 20 Alkylgermanyl, unsubstituted or substituted C6 to C 30 Arylgermyl, unsubstituted or substituted C2 to C 30 Heteroarylgermyl, unsubstituted or substituted C6 to C 30 triarylmethyl, or unsubstituted or substituted C2 to C 30 triheteroarylmethyl, wherein when e1 is 2, 3 or 4, each R 41 are the same as or different from each other, and when e2 is 2, 3 or 4, each R 42 are the same as or different from each other, e1 and e2 are each independently 0, 1, 2, 3 or 4, or Optionally, Two adjacent R 41 and / or two adjacent R 42 further linked together to form unsubstituted or substituted C4 to C 20 Alicyclic ring, unsubstituted or substituted C3 to C 20 Heteroalicyclic ring, unsubstituted or substituted C6 to C 20 Aromatic ring, or unsubstituted or substituted C2 to C 20 heteroaromatic rings; and The wavy lines indicate the connection locations. 2 . The organic light emitting diode according to claim 1 , wherein the light emitting layer further comprises a second exciton generating layer disposed opposite to the first exciton generating layer with respect to the light emitting material layer.

3. The organic light emitting diode according to claim 2, wherein the second exciton generating layer comprises a third compound and a fourth compound, wherein the third compound includes the organic compound having the structure of Chemical Formula 1 or Chemical Formula 3, and wherein the fourth compound includes the organic compound having the structure of Chemical Formula 5. 4 . The organic light emitting diode according to claim 1 , wherein a difference between a highest occupied molecular orbital (HOMO) energy level of the first compound and a HOMO energy level of the second compound is 0.2 eV or more and 0.8 eV or less. 5 . The organic light emitting diode according to claim 1 , wherein a difference between a higher HOMO energy level among a highest occupied molecular orbital (HOMO) energy level of the first host and a HOMO energy level of the second host and a HOMO energy level of the first compound is 0.3 eV or less. 6 . The organic light emitting diode according to claim 1 , wherein a difference between a lowest unoccupied molecular orbital (LUMO) energy level of the first compound and a LUMO energy level of the second compound is 0.2 eV or more and 0.8 eV or less. 7 . The organic light emitting diode according to claim 1 , wherein a difference between a lower LUMO energy level of the lowest unoccupied molecular orbital (LUMO) energy level of the first host and the LUMO energy level of the second host and the LUMO energy level of the second compound is 0.3 eV or less.

8. The organic light emitting diode according to claim 1, wherein the lowest excited triplet energy level of the first compound is higher than the lowest excited triplet energy level of the second compound, and wherein the lowest excited triplet energy level of the second compound is higher than the lowest excited triplet energy level of the second host.

9. The organic light emitting diode according to claim 1, wherein the first compound having the structure of Chemical Formula 1 and the first host are each independently at least one of the following:

10. The organic light emitting diode according to claim 1, wherein the first compound having the structure of Chemical Formula 3 and the first host are each independently at least one of the following:

11. The organic light emitting diode according to claim 1, wherein the second compound is at least one of the following:

12. The organic light emitting diode according to claim 1, wherein the second host is at least one of the following:

13. The organic light emitting diode according to claim 1, wherein the light emitting body comprises an organic metal compound having a structure of the following Chemical Formula 11: Chemical formula 11 in, In Chemical Formula 11, R 51 To R 56 are each independently hydrogen, deuterium, halogen, cyano, unsubstituted or substituted C1 to C 20 Alkyl, unsubstituted or substituted C2 to C 20 alkenyl, unsubstituted or substituted C2 to C 20 Alkynyl, unsubstituted or substituted C1 to C 20 Alkoxy, amino, unsubstituted or substituted C1 to C 20 Alkylamino, unsubstituted or substituted C1 to C 20 Alkylsilyl, unsubstituted or substituted C4 to C 30 Cycloalkyl, unsubstituted or substituted C3 to C 30 Heterocycloalkyl, unsubstituted or substituted C6 to C 30 Aryl, unsubstituted or substituted C2 to C 30 heteroaryl, unsubstituted or substituted C7 to C 30 Arylalkyl, unsubstituted or substituted C3 to C 30 heteroarylalkyl, unsubstituted or substituted C6 to C 30 Aryloxy, unsubstituted or substituted C2 to C 30 heteroaryloxy, unsubstituted or substituted C6 to C 30 Arylamino, unsubstituted or substituted C2 to C 30 heteroarylamino, unsubstituted or substituted C6 to C 30 Arylsilyl, unsubstituted or substituted C2 to C 30 heteroarylsilyl, unsubstituted or substituted C1 to C 20 Alkylgermanyl, unsubstituted or substituted C6 to C 30 Arylgermyl, unsubstituted or substituted C2 to C 30 Heteroarylgermyl, unsubstituted or substituted C6 to C 30 triarylmethyl, or unsubstituted or substituted C2 to C 30 triheteroarylmethyl, wherein when f1 is 2, 3 or 4, each R 51 are the same as or different from each other, and when f2 is 2, 3 or 4, each R 52 The same or different from each other, when f3 is 2, each R 53 The same or different from each other, when f4 is 2 or 3, each R 54 are the same as or different from each other, and when f5 is 2, 3 or 4, each R 55 the same as or different from one another; f1, f2 and f5 are each independently 0, 1, 2, 3 or 4; f3 is 0, 1, or 2; as well as f4 is 0, 1, 2, or 3.

14. The organic light emitting diode according to claim 1, wherein the light emitting body is at least one of the following: 15 . The organic light emitting diode according to claim 1 , wherein the first compound and the second compound in the first exciton generating layer are mixed in a weight ratio of 4:1 to 1:

4. 16 . The organic light emitting diode according to claim 1 , wherein the light emitting layer further comprises a hole blocking layer disposed between the light emitting material layer and the second electrode. 17 . The organic light emitting diode according to claim 1 , wherein the light emitting layer further comprises an electron blocking layer disposed between the light emitting material layer and the first electrode.

18. The organic light emitting diode according to claim 1, wherein the light emitting layer comprises: A first light emitting portion disposed between the first electrode and the second electrode and comprising a first light emitting material layer; A second light emitting portion disposed between the first light emitting portion and the second electrode and comprising a second light emitting material layer; as well as a first charge generation layer provided between the first light emitting portion and the second light emitting portion, and At least one of the first light-emitting material layer and the second light-emitting material layer includes the first host, the second host and the light-emitting body.

19. An organic light emitting diode according to claim 18, wherein the first light emitting material layer comprises the first host, the second host and the light emitting body, wherein the first exciton generation layer is arranged between the first electrode and the first light emitting material layer or between the first light emitting material layer and the first charge generation layer. 20 . The organic light emitting diode according to claim 19 , wherein the first light emitting portion further comprises a second exciton generating layer disposed opposite to the first exciton generating layer with respect to the first light emitting material layer.

21. The organic light emitting diode according to claim 18, wherein the light emitting layer further comprises: A third light emitting portion disposed between the second light emitting portion and the second electrode and comprising a third light emitting material layer; as well as A second charge generation layer is provided between the second light emitting portion and the third light emitting portion. 22 . The organic light emitting diode according to claim 21 , wherein at least one of the first light emitting material layer and the third light emitting material layer comprises the first host, the second host, and the light emitting body.

23. An organic light-emitting device, comprising: substrate; and An organic light emitting diode according to any one of claims 1 to 22 is disposed over the substrate.

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