KR102515820B1 - Organic compounds, organic light emitting diode and organic light emittid device having the compounds - Google Patents

Abstract

In the present invention, an imidazole or thiazole moiety that functions as an electron acceptor is added to an indenofluorene-substituted triaryl amine moiety that functions as an electron donor. It relates to an organic compound linked through an aromatic linker. Since it contains both an electron donor and an electron acceptor moiety in one molecule, charge can easily move in the molecule and the luminous efficiency can be improved. In addition, since the nitrogen atom, which is a part of the electron donor, is connected to the indenofluorene ring, which is a condensed aromatic ring having a rigid structure, the three-dimensional structure of the molecule is limited. Therefore, the organic compound of the present invention can be used as a delayed fluorescence dopant emitting blue light of high color purity. By applying the organic compound of the present invention, it can be used in organic light emitting devices such as organic light emitting diodes, display devices, and lighting devices having low driving voltage and excellent luminous efficiency and color purity.

Description

Organic compounds, organic light emitting diodes and organic light emitting devices containing the same

The present invention relates to an organic compound, and more particularly, to an organic compound that can be applied to a light emitting layer of an organic light emitting diode due to its excellent light emitting efficiency, an organic light emitting diode and an organic light emitting device including the organic compound.

As one of the currently widely used flat display devices, the technology of an organic light emitting diode device is rapidly developing. Organic light emitting diodes (OLEDs) are formed of a thin organic thin film of less than 2000 Å, and can implement images in a single direction or in both directions depending on the configuration of electrodes used. In addition, an organic light emitting diode display, which is one of organic light emitting devices including organic light emitting diodes, can form elements on a flexible transparent substrate such as plastic, so that a flexible or foldable display device can be realized. In addition, the organic light emitting diode display can be driven at a low voltage and has excellent color purity, so it has great advantages over a liquid crystal display device (LCD).

An organic light emitting diode includes a hole injection electrode (anode), an electron injection electrode (cathode), and an organic light emitting layer formed between the anode and the cathode. In order to increase luminous efficiency, the organic light emitting layer may include a hole injection layer, a hole transport layer, a light emitting material layer, an electron transport layer, and an electron injection layer sequentially stacked on the hole injection electrode. At this time, holes injected from the anode and electrons injected from the cathode combine in the light emitting material layer to form excitons (exciton) to enter an unstable excited state and then to a stable ground state ( It returns to the ground state and emits light. External quantum efficiency (EQE; η _ext ) of the light emitting material applied to the light emitting material layer can be calculated by the following formula (1).

(η _S/T is the singlet/triplet ratio, г is the charge balance factor; Φ is the radiative quantum efficiency; η _out-coupling is the light-extraction efficiency (out- coupling efficiency)

The exciton generation efficiency (η _S/T ) is the rate at which generated excitons are converted into light, and has a limiting value of up to 0.25 for fluorescent materials. Theoretically, when a hole and an electron meet to form an exciton, a singlet exciton in the form of paired spin and a triplet exciton in the form of unpaired spin are formed according to the arrangement of spins. It is produced in a ratio of 1:3. This is because in fluorescent materials, only singlet excitons participate in light emission, and the remaining 75% of triplet excitons do not participate in light emission.

The charge balance factor (г) means the balance of holes and electrons forming excitons, and generally has a value of '1' assuming a 1:1 matching of 100%. Radiant quantum efficiency (Φ) is a value related to the actual luminous efficiency of a light emitting material, and depends on the photoluminescence (PL) of a dopant in a host-dopant system.

Light-extraction efficiency (η _out-coupling ) is a ratio of light extracted to the outside among light emitted from a light emitting material. In general, when a thin film is formed by thermally depositing an isotropic light emitting material, individual light emitting molecules do not have a certain directionality and exist in a disordered state. Light-extraction efficiency in such a random orientation state is generally assumed to be 0.2. Therefore, when the four elements shown in Equation (1) are combined, the maximum luminous efficiency of the organic light emitting diode using the fluorescent material is only about 5 to 7%.

On the other hand, phosphorescent materials have a light-emitting mechanism that converts both singlet excitons and triplet excitons into light. Phosphorescent materials convert singlet excitons into triplets through intersystem crossing (ISC). Therefore, when a phosphorescent material using both singlet excitons and triplet excitons is used, the low luminous efficiency of the fluorescent material can be improved. When a metal complex containing a heavy metal such as Ir or Pt is used as a phosphorescent material, a transition from a triplet state to a singlet state is possible due to strong spin-orbit coupling by the heavy metal element. However, in particular, the color purity of blue phosphor materials is difficult to apply to display devices, and the lifetime is also very short, so they do not reach the level of commercialization.

In particular, the blue phosphorescent host should be higher than the triplet energy of the phosphorescent dopant material in order to prevent back energy transfer of the blue phosphorescent dopant to the host. However, when the organic aromatic compound has an increased conjugated structure or a fused ring, the triplet energy is drastically lowered, so organic molecules that can be used as a blue phosphorescent host are extremely limited. In addition, in order to have a high triplet energy, the phosphorescent host is designed to have a fairly wide energy band gap. Charge injection and transport are delayed due to the phosphorescent host material having a wide energy bandgap, and accordingly, the driving voltage of the organic light-emitting diode increases, adversely affecting power consumption, and electrical stress is applied to the material constituting the light emitting layer. However, a problem occurred in that the lifetime characteristics of the device were deteriorated.

SUMMARY OF THE INVENTION An object of the present invention is to provide an organic light emitting diode and an organic light emitting device that can improve light emitting efficiency, reduce power consumption by lowering a driving voltage using the organic compound, and improve device lifetime.

According to one aspect of the present invention, the present invention provides imidazole acting as an electron acceptor to a triaryl amine moiety substituted with an indenofluorene ring acting as an electron donor. or an organic compound in which thiazole moieties are linked through an aromatic linker.

For example, the remaining two amine atoms constituting the electron donor may be connected with a homo aryl group except for the indenofluorene ring, and the aromatic linker between the electron donor and the electron acceptor may be a homo arylene ring.

According to another aspect of the present invention, the present invention provides an organic light emitting diode and an organic light emitting device in which the organic compound described above is applied to an organic light emitting layer.

For example, the organic compound may be applied to the light emitting material layer.

In one exemplary embodiment, the organic compound of the present invention may be used as a dopant of the light emitting material layer.

The organic compound according to the present invention acts as an electron donor and includes imidazole or thiazole ( thiazole) moieties are linked through an aromatic linker.

A triaryl amine moiety having an indenofluorene ring in which five aromatic rings are condensed is used as an electron donor, and an imidazole or thiazole moiety is used as an electron acceptor. Indenofluorene ring constituting the electron donor As the steric hindrance between the electron donor and the electron acceptor increases, the dihedral angle between the electron donor and the electron acceptor increases. While the formation of the conjugate structure between the triaryl amine moiety having an indenofluorene condensed aromatic ring that functions as an electron donor and the imidazole / thiazole moiety that functions as an electron acceptor is limited, the highest organic compound Luminous efficiency can be improved while being easily separated into an occupied molecular orbital (HOMO) energy state and an energy state of a lowest unoccupied molecular orbit (LUMO).

In addition, a dipole is formed from the triaryl amine moiety that functions as an electron donor to the imidazole/thiazole moiety that functions as an electron acceptor, and as the dipole moment inside the molecule increases, the luminous efficiency further increases. can be improved

In addition, the triaryl amine moiety that functions as an electron donor and has an indenofluorene condensed aromatic ring is linked to an imidazole/thiazole moiety that is an electron acceptor through a homo arylene group or a hetero arylene group such as phenylene. Since the distance between the electron donor and the electron acceptor increases, the overlap between the HOMO and the LUMO decreases, so the difference between the triplet energy level (T ₁ ) and the singlet energy level (S ₁ ) (ΔE _ST ) can be reduced . It is possible to minimize the red shift problem of light emitted from the organic light emitting layer including the organic compound according to the present invention due to steric hindrance through the linking group.

Moreover, since the triaryl amine moiety functioning as an electron donor has an indenofluorene ring, which is a rigid condensed aromatic ring, the three-dimensional conformation of the molecule is greatly restricted. When the organic compound according to the present invention emits light, there is no energy loss due to a change in the three-dimensional structure of the molecule, and since the emission spectrum can be limited to a specific range, high color purity can be realized.

Therefore, by using the organic compound of the present invention as a dopant of an organic light emitting layer constituting an organic light emitting diode, for example, a light emitting material layer, the driving voltage of the light emitting device can be lowered and the light emitting efficiency can be improved. Since it can be driven at a low voltage, the structure of the light emitting device is not collapsed due to heat generated at a high voltage. In addition, since the light emitting efficiency is improved and the current density of the light emitting element can be reduced, the load when driving the light emitting element is reduced and the life of the element is increased.

As a result, by applying the organic compound according to the present invention, it is possible to implement an organic light emitting device such as an organic light emitting diode capable of emitting blue light, an organic light emitting diode display device, and a lighting device with improved light emitting efficiency and device lifetime characteristics. .

1 is a schematic diagram for explaining a light emitting mechanism when an organic compound according to an exemplary embodiment of the present invention is used as a delayed fluorescent material.
2 is a cross-sectional view schematically illustrating an organic light emitting diode in which an organic compound is applied to an organic light emitting layer according to an exemplary embodiment of the present invention.
3 is a schematic diagram for explaining an energy level of a material used as a host when an organic compound according to an exemplary embodiment of the present invention is used as a delayed fluorescent material.
4 is a cross-sectional view schematically illustrating an organic light emitting diode in which an organic compound is applied to an organic light emitting layer according to another exemplary embodiment of the present invention.
5 is a cross-sectional view schematically illustrating an organic light emitting diode display as an example of an organic light emitting diode having an organic light emitting diode applied to an organic light emitting layer according to an exemplary embodiment of the present invention.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings when necessary.

[organic compound]

The organic compound according to the present invention comprises a triaryl amine moiety having an indenofluorene aromatic ring having a rigid chemical structure and functioning as an electron donor, and an aromatic linker suitable for the triaryl amine moiety. It contains an imidazole or thiazole group that is linked through and functions as an electron acceptor. The organic compound according to the present invention may be represented by Formula 1 below.

Formula 1

(In Formula 1, R ₁ to R ₄ are each independently selected from the group consisting of hydrogen, deuterium, tritium, unsubstituted or substituted C ₁ ~ C ₂₀ alkyl group and unsubstituted or substituted C ₁ ~ C ₂₀ alkoxy group ; R ₅ is represented by Formula 2; Ar ₁ and Ar ₂ are each independently selected from an unsubstituted or substituted C ₅ to C ₃₀ homoaryl group and an unsubstituted or substituted C ₄ to C ₃₀ heteroaryl group. selected)

Formula 2

(In Formula 2, R ₆ and R ₇ are each independently selected from the group consisting of an unsubstituted or substituted C ₅ ~ C ₃₀ homoaryl group and an unsubstituted or substituted C ₄ ~ C ₃₀ heteroaryl group; X is S or NR ₈ , R ₈ is selected from the group consisting of an unsubstituted or substituted C ₅ ~ C ₃₀ homoaryl group and an unsubstituted or substituted C ₄ ~ C ₃₀ heteroaryl group; L ₁ is an unsubstituted or substituted C ₅ ~ C ₃₀ selected from the group consisting of a homo arylene group and an unsubstituted or substituted C ₄ ~ C ₃₀ hetero arylene group)

In the present specification, 'unsubstituted' or 'unsubstituted' means that a hydrogen atom is substituted, and in this case, the hydrogen atom includes light hydrogen, heavy hydrogen, and tritium.

In the present specification, the substituent in 'substituted' is, for example, a C ₁ ~ C ₂₀ alkyl group unsubstituted or substituted with a halogen atom, a cyano group, and/or a nitro group, an unsubstituted or substituted with a halogen atom, a cyano group, and/or a nitro group. C ₁ ~C ₂₀ alkoxy group, halogen atom, cyano group, alkyl halide group such as -CF ₃ , hydroxy group unsubstituted or substituted with a halogen atom, cyano group and/or nitro group, carboxy group, carbonyl group, amine group , C ₁ ~C ₁₀ alkyl substituted amine group, C ₅ ~C ₃₀ aryl substituted amine group, C ₄ ~C ₃₀ heteroaryl substituted amine group, nitro group, hydrazyl group, sulfonic acid group, C ₁ ~C ₂₀ Alkyl silyl group, C ₁ ~C ₂₀ Alkoxy silyl group, C ₃ ~C ₃₀ Cycloalkyl silyl group, C ₅ ~C ₃₀ Aryl silyl group, C ₄ ~C ₃₀ Heteroaryl silyl group, C ₅ ~C ₃₀ Aryl group , C ₄ ~ C ₃₀ heteroaryl group, C ₅ ~ C ₃₀ homo aralkyl group, C ₄ ~ C ₃₀ hetero aralkyl group, C ₅ ~ C ₃₀ homo aralkoxy group or C ₄ ~ C ₃₀ hetero aralkoxy group, and the like. However, the present invention is not limited thereto.

In the present specification, the term 'hetero' used in 'heteroaromatic ring', 'heterocycloalkylene group', 'heteroaryl group', 'heteroaralkyl group', 'heteroaraloxyl group', 'heteroarylamine group', etc. It means that one or more of the carbon atoms constituting the aromatic or alicyclic ring, for example, 1 to 5 carbon atoms are substituted with one or more heteroatoms selected from the group consisting of N, O, S, and combinations thereof. do.

For example, when R ₁ to R ₄ in Formula 1 and Formula 2 are each an alkyl group or an alkoxy group, and/or Ar ₁ , Ar ₂ , R ₆ and/or R ₇ are each independently substituted with an alkyl group or an alkoxy group, These alkyl groups and/or alkoxy groups may be straight-chain or branched C ₁ -C ₂₀ alkyl groups or alkoxy groups, preferably C ₁ -C ₁₀ alkyl groups or alkoxy groups.

In addition, when Ar _{1 ,} Ar ₂ , R ₆ , R ₇ and/or R ₈ in Formulas 1 and 2 are aromatic functional groups, these aromatic functional groups may each independently be an unsubstituted or substituted phenyl group, a biphenyl group, a terphenyl group, tetraphenyl group, naphthyl group, anthracenyl group, indenyl group, phenalenyl group, phenanthrenyl group, azulenyl group, pyrenyl group, fluorenyl group, tetracenyl group, indacenyl group or spiro fluorenyl group. or fused homoaromatic ring, and/or pyrrolyl group, pyridinyl group, pyrimidinyl group, pyrazinyl group, pyridazinyl group, triazinyl group, tetrazinyl group, imidazolyl group, pyrazolyl group, indole diary, carbazolyl group, benzocarbazolyl group, dibenzocarbazolyl group, indolocarbazolyl group, indenocarbazolyl group, benzofuranocarbazolyl group, benzothienocarbazolyl group, quinolinyl group, isoquinoyl group Nyl group, phthalazinyl group, quinoxalinyl group, cinolinyl group, quinazolinyl group, phthalazinyl group, quinoxalinyl group, cinolinyl group, quinazolinyl group, benzoquinolinyl group, benzoisoquinolinyl group, benzoquinazoli Nyl group, benzoquinoxalinyl group, acridinyl group, phenanthrolinyl group, furanyl group, pyranyl group, oxazinyl group, oxazolyl group, oxadiazolyl group, triazolyl group, dioxynyl group, benzofuranyl group, dibenzofura It may be an uncondensed or condensed heteroaromatic ring such as a yl group, a thiopyranyl group, a thiazinyl group, a thiophenyl group or an N-substituted spiro fluorenyl group.

For example, in Formula 1 and Formula 2, Ar _{1 ,} Ar ₂ , R ₆ , R ₇ and/or R ₈ are each independently a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, an anthracenyl group, a fluorenyl group, or a spy group. A homoaryl group such as a rofluorenyl group and/or a benzothiophenyl group, a dibenzothiophenyl group, a benzofuranyl group, a dibenzofuranyl group, a pyrrolyl group, a pyridinyl group, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group group, triazinyl group, tetrazinyl group, imidazolyl group, pyrazolyl group, indolyl group, carbazolyl group, benzocarbazolyl group, dibenzocarbazolyl group, indolocarbazolyl group, indenocarbazolyl group, benzofur Ranocarbazolyl group, benzothienocarbazolyl group, quinolinyl group, isoquinolinyl group, phthalazinyl group, quinoxalinyl group, cinolinyl group, quinazolinyl group, phthalazinyl group, quinoxalinyl group, cinolinyl group , It may be a heteroaryl group such as a quinazolinyl group, a benzoquinolinyl group, a benzoisoquinolinyl group, a benzoquinazolinyl group, or a benzoquinoxalinyl group.

At this time, when the number of aromatic rings constituting Ar _{1 ,} Ar ₂ , R ₆ , R ₇ and/or R ₈ in Formulas 1 and 2 increases, the conjugated structure in the entire organic compound becomes too long, The band gap of the organic compound may be excessively reduced. Therefore, preferably, the number of aromatic rings constituting Ar _{1 ,} Ar ₂ , R ₆ , R ₇ and/or R ₈ in Formulas 1 and 2 is 1 to 2, more preferably 1. In addition, with respect to charge injection and transfer characteristics, in Formulas 1 and 2 _{, Ar 1 ,} Ar ₂ , R ₆ , R ₇ and/or R ₈ may each be a 5-membered ring to a 7-membered ring. It may be a 7-membered ring, particularly preferably a 6-membered ring. For example, in Formulas 1 and 2, Ar _{1 ,} Ar ₂ , R ₆ , R ₇ and/or R ₈ are each independently a substituted or unsubstituted phenyl group, a biphenyl group, a naphthyl group, a biphenyl group, a pyrrole group, It may be a dazole group, a pyrazole group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a furanyl group, or a thiophenyl group.

Meanwhile, in one non-limiting embodiment, L ₁ , which is a linker in Formula 2, mediates between an electron donor moiety and an electron acceptor moiety, and may be an unsubstituted or substituted aromatic linker. For example, when L ₁ is an unsubstituted or substituted C ₅ ~ C ₃₀ arylene group, L ₁ is an unsubstituted or substituted phenylene group, a biphenylene group, a terphenylene group, Tetraphenylene, indenylene, naphthylene, azulenylene, indacenylene, acenaphthylene, fluorenylene ), spiro-fluorenylene group, phenalenylene group, phenanthrenylene group, anthracenylene group, fluoranthrenylene group, triphenylenylene group, pi Composed of pyrenylene, chrysenylene, naphthacenylene, picenylene, perylenylene, pentaphenylene and hexacenylene can be selected from the group

In another optional embodiment, when L ₁ is an unsubstituted or substituted C ₄ ~ C ₃₀ heteroarylene group, L ₁ is an unsubstituted or substituted pyrrolylene group, imidazolylene group, pyra Pyrazolylene, pyridinylene, pyrazinylene, pyrimidinylene, pyridazinylene, isoindolylene, indolylene , indazolylene, purinylene, quinolinylene, isoquinolinylene, benzoquinolinylene, phthalazinylene, naphthyl naphthyridinylene, quinoxalinylene, quinazolinylene, benzoquinolinylene, benzoisoquinolinylene, benzoquinazolinylene, benzoquinoxalinylene, cinnoli Cinnolinylene, phenanthridinylene, acridinylene, phenanthrolinylene, phenazinylene, benzoxazolylene, benzimidazolylene (benzimidazolylene), furanylene, benzofuranylene, thiophenylene, benzothiophenylene, thiazolylene, isothiazolylene, benzo Thiazolylene group (benzothiazolylene group), isoxazolylene group (isoxazolylene group), oxazolylene group (oxazolylene group), triazolylene group, tetrazolylene group, oxadiazolyl group (oxadiazolyl ene), triazinylene, benzofuranylene, dibenzofuranylene, benzofuranyldibenzofuranylene, benzothienobenzofuranylene, benzothienodibenzofuranylene, benzothio A phenylene group, a dibenzothiophenylene group, a benzothietobenzothiophenylene group, a benzothienodibenzothiophenylene group, a carbazolylene group, a benzocarbazolylene group, a dibenzocarbazolylene group, an indolocarbazolylene group, and It may be selected from the group consisting of a nocarbazolylene group, a benzofurocarbazolylene group, a benzothienocarbazolylene group, an imidazopyrimidinylene group, and an imidazopyridinylene group.

In one exemplary embodiment, when the number of aromatic rings constituting L ₁ increases, the conjugated structure in the entire organic compound becomes too long, and thus the band gap of the organic compound may be excessively reduced. Therefore, the number of aromatic rings constituting L ₁ is preferably 1 to 2, more preferably 1. In addition, with respect to charge injection and transfer characteristics, L ₁ may be a 5-membered ring or a 7-membered ring, particularly a 6-membered ring. It may be desirable to For example, L ₁ is an unsubstituted or substituted phenylene group, biphenylene group, pyrrolylene group, imidazolylene group, pyrazolylene group, pyridinylene group, pyrazinylene group, pyrimidinylene group, pyridazinylene group, It may be a furanylene group or a thiophenylene group.

The organic compounds represented by Chemical Formulas 1 to 2 may function as an electron donor, have a triaryl amine moiety having an indenofluorene condensed aromatic ring having a rigid structure, and have a triaryl amine moiety An imidazole ring or thiazole ring that can function as an electron acceptor is connected through the aromatic linking group. 3 of the organic compound of the present invention synthesized by forming a chemical bond between an indenofluorene ring and a heteroaromatic ring through an aromatic linking group because the steric hindrance of the indenofluorene ring composed of five aromatic rings is large Dimensional conformation is limited. Accordingly, the organic compound according to the present invention has a rigid structure, thereby improving thermal stability. When organic compounds represented by Chemical Formulas 1 to 2 emit light, there is no energy loss due to a change in the three-dimensional structure of the molecule, and since the emission spectrum can be limited to a specific range, good color purity can be realized.

In particular, by using the organic compound according to the present invention, low-voltage driving is possible, so power consumption can be reduced, and a light emitting diode with improved lifespan can be implemented. As an example, the organic compound according to the present invention can be used as a dopant of an organic light emitting layer constituting an organic light emitting diode, and in particular has so-called delayed florescence characteristics, which will be described.

1 is a schematic diagram for explaining a light emitting mechanism when an organic compound according to the present invention is used as a delayed fluorescent compound. Delayed fluorescence can be divided into thermally activated delayed fluorescence (TADF) and field activated delayed fluorescence (FADF). Triplet excitons are activated by heat or an electric field, and conventional fluorescence It is possible to realize so-called super-fluorescence that exceeds the maximum luminous efficiency in materials.

That is, in the delayed fluorescent compound, triplet excitons are activated by heat or an electric field generated when the device is driven, and the triplet excitons also participate in light emission. In general, a delayed fluorescent compound has both an electron donor moiety and an electron acceptor moiety, and thus can be converted into an intramolecular charge transfer (ICT) state. When a delayed fluorescence compound capable of ICT is used as a dopant, excitons having a singlet energy level (S ₁ ) and an exciton having a triplet energy level (T ₁ ) in the delayed fluorescence compound move to an intermediate ICT state, and the bottom State (ground state, S ₀ ) transitions (S ₁ → ICT←T ₁ ). Since excitons having a singlet energy level (S ₁ ) and excitons having a triplet energy level (T ₁ ) both participate in light emission, the internal quantum efficiency is improved, and thus the luminous efficiency is improved.

In conventional fluorescent materials, since the Highest Occupied Molecular Orbital (HOMO) and the Lowest Unoccupied Molecular Orbital (LUMO) are spread throughout the molecule, there is a transition between singlet and triplet states. Interchangeability is not possible (selection rule). However, since the overlapping of HOMO and LUMO orbitals in the compound having the ICT state is small, the interaction between the orbits of the HOMO state and the orbits of the LUMO state is small. Therefore, the spin state change of an electron does not affect other electrons, and a new charge transfer band (CT band) that does not follow the selection rule is formed.

That is, since the electron acceptor moiety and the electron donor moiety in the delayed fluorescent compound are spaced apart in the molecule, the dipole moment in the molecule exists in a large polarization state. In a state where the dipole moment is polarized, the interaction between the orbits of the HOMO and LUMO states becomes small, and a transition from the triplet state and the singlet state to the intermediate state (ICT) becomes possible. Accordingly, excitons having a singlet energy level (S ₁ ) as well as excitons having a triplet energy level (T ₁ ) participate in light emission. That is, when the light emitting device is driven, excitons having a singlet energy level (S ₁ ) of 25% and excitons having a triplet energy level (T ₁ ) of 75% are transitioned to an intermediate state (ICT) by heat or an electric field. Since light emission occurs while falling back to the ground state (S ₀ ), the internal quantum efficiency theoretically becomes 100%.

A dopant for realizing delayed fluorescence needs to have the following characteristics. The dopant must have an electron donor moiety and an electron acceptor moiety in one molecule at the same time to implement an ICT state. The dopant usually has an ICT state complex (ICT complex), and it has an electron donor moiety and an electron acceptor moiety in one molecule at the same time, so electron transfer easily occurs in the molecule. That is, in the ICT complex, one electron moves from the electron-donor moiety to the electron-acceptor portion under specific conditions, and charge separation occurs within the molecule.

In addition, in order for energy transfer to occur in both the triplet state and the singlet state, the dopant for realizing delayed fluorescence has a difference (ΔE _ST ) between the singlet energy level (S ₁ ) and the triplet energy level (T ₁ ) of 0.3 eV or less, for example 0.05 to 0.3 eV. In this case, a material with a small energy difference between the singlet state and the triplet state not only exhibits fluorescence as intersystem crossing (ISC) occurs, in which energy is transferred from the singlet state to the triplet state, but also exhibits heat at room temperature. Reverse Inter System Crossing (RISC) is performed from a triplet state to a singlet state having higher energy by energy or an electric field, and delayed fluorescence is exhibited as the singlet state transitions to the ground state. In the case of delayed fluorescence, since efficiency of up to 100% can be obtained theoretically, internal quantum efficiency equivalent to that of conventional phosphorescent materials containing heavy metals can be realized. However, due to the bonding structure and structural distortion of the electron donor-electron acceptor of the conventional delayed fluorescence compound, an additional charge transfer transition (CT transition) is induced, resulting in a wide spectrum when emitting, resulting in high color purity. has the disadvantage of lowering the

Organic compounds represented by Chemical Formulas 1 to 2 function as an electron donor and include a triaryl amine moiety having an indenofluorene ring and an imidazole or thiazole moiety that is a heteroaromatic ring that functions as an electron acceptor. Because they coexist in the molecule, they can show delayed fluorescence characteristics. In particular, since the steric hindrance between the indenofluorene ring and the imidazole or thiazole ring is large, the formation of a conjugated structure is limited, and it is easily separated into HOMO and LUMO states. As dipoles are formed between the triaryl amine moiety having an indenofluorene ring and the imidazole or thiazole moiety, the dipole moment inside the molecule increases, thereby improving luminous efficiency. The electron donor and electron acceptor coexist in the molecule, reducing the overlap of the HOMO and LUMO of the molecule.

In addition, since the triaryl amine moiety and the imidazole/thiazole moiety are connected through an aromatic linking group (represented by L ₁ in Formula 2), the overlap between HOMO and LUMO is further reduced, and thus the triplet energy level and The energy level difference (ΔE _ST ) of the singlet energy level can be reduced. In particular, the three-dimensional structure between the triaryl amine moiety and the imidazole/thiazole moiety is restricted because the nitrogen atoms constituting the triaryl amine moiety are connected by an indenofluorene ring, which is a rigid condensed aromatic ring. . When emitting light, there is no energy loss, efficiency is excellent, and blue light emission of high color purity can be implemented.

In particular, when organic compounds represented by Chemical Formulas 1 to 2 are used as dopants in the light emitting material layer, the triplet energy level of the organic compounds represented by Chemical Formulas 1 to 2 is lower than the triplet energy of conventional phosphorescent materials, The band gap is narrower than conventional phosphorescent materials. Therefore, the organic host used together with the organic compounds represented by Chemical Formulas 1 to 2 does not need to have a triplet energy level as high as that of conventional phosphorescent materials and does not need to have a wide band gap. Therefore, it is not necessary to use an organic compound having a high triplet energy, which has been a limitation when applying a conventional phosphorescent material, as a host, and a phosphorescent host having a wide energy bandgap is not necessarily used. Due to the use of a host having a wide energy bandgap, charge injection and transport are delayed, and accordingly, the driving voltage of the light emitting diode increases, power consumption increases, and lifespan characteristics of the device decrease.

In one exemplary embodiment, the organic compound according to the present invention includes an organic compound represented by Formula 3 below.

Formula 3

(In Formula 3, R ₁ to R ₄ are each the same as defined in Formula 1; R ₉ and R ₁₀ are each independently hydrogen, deuterium, tritium, C ₁ ~ C ₂₀ alkyl group, C ₁ ~ C ₂₀ alkoxy group , C ₅ ~ C ₃₀ selected from the group consisting of a homo aryl group and a C ₄ ~ C ₃₀ hetero aryl group; R ₁₁ is represented by Formula 4 below)

formula 4

(X in Formula 4 is the same as defined in Formula 2)

More specifically, the organic compound according to the present invention may be any one compound represented by Formula 5 below.

Formula 5

The organic compounds represented by Chemical Formulas 3 to 5 function as an electron donor, and a triaryl amine moiety having an indenofluorene ring having a rigid structure and an imidazole/thiazole moiety functioning as an electron acceptor are suitable conjugated structures. It is connected by a phenylene ring having A triaryl amine moiety as an electron donor and an imidazole/thiazole moiety as an electron acceptor are present in one molecule to increase the dipole moment, and the HOMO and LUMO are easily separated to increase the dipole moment. Therefore, the organic compounds represented by Chemical Formulas 3 to 5 can be applied as delayed fluorescent materials, and the organic compounds represented by Chemical Formulas 3 to 5 can be used to improve light emitting efficiency and color purity of organic light emitting diodes. . In addition, by applying the organic compounds represented by Chemical Formulas 3 to 5 to the organic light emitting diode, the driving voltage of the organic light emitting diode can be lowered to reduce power consumption, and electrical stress to the organic material constituting the light emitting layer can be reduced to improve the quality of the device. Life characteristics can be improved.

[Organic Light-Emitting Diode and Organic Light-Emitting Device]

As described above, by applying the organic compounds represented by Chemical Formulas 1 to 5 to the organic light emitting layer constituting the organic light emitting diode, it is possible to obtain a particularly high purity light emitting color and reduce power consumption by lowering the driving voltage, A light emitting device with improved lifespan characteristics may be implemented. explain this. 2 is a cross-sectional view schematically illustrating an organic light emitting diode in which an organic compound is applied to an organic light emitting layer according to an exemplary embodiment of the present invention.

As shown in FIG. 2 , the organic light emitting diode 100 according to the first embodiment of the present invention includes a first electrode 110 and a second electrode 120 facing each other, and the first and second electrodes 110 , 120) and an organic light emitting layer 130 positioned between them. In an exemplary embodiment, the organic light emitting layer 130 may include a hole injection layer (HIL) 140 sequentially stacked from the first electrode 110, a hole transfer layer (HTL) 150, and a light emitting material. It includes an emissive material layer (EML) 160, an electron transfer layer (ETL) 170 and an electron injection layer (EIL) 180.

The first electrode 110 may be an anode supplying holes to the light emitting material layer 160 . The first electrode 110 is preferably formed of a conductive material having a relatively high work function value, for example, transparent conductive oxide (TCO). In an exemplary embodiment, the first electrode 110 is indium-tin-oxide (ITO), indium-zinc-oxide (IZO), or indium-tin-zinc-oxide. (indium-tin-zinc oxide; ITZO), tin oxide (SnO), zinc oxide (ZnO), indium-copper-oxide (ICO) and aluminum:zinc oxide (Al:ZnO; AZO). It can be done.

The second electrode 120 may be a cathode supplying electrons to the light emitting material layer 160 . The second electrode 120 is formed of a conductive material having a relatively small work function value, for example, aluminum (Al), magnesium (Mg), calcium (Ca), silver (Ag), or an alloy or combination thereof having reflective properties. It can be made of good material.

The hole injection layer 140 is positioned between the first electrode 110 and the hole transport layer 150, and improves interface characteristics between the inorganic first electrode 110 and the organic hole transport layer 150. In one exemplary embodiment, the hole injection layer 140 is 4,4 ', 4 "-tris (3-methylphenylamino) triphenylamine (4,4 ', 4 "-Tris (3-methylphenylamino) triphenylamine; MTDATA), 4,4', 4"-tris (N, N-diphenyl-amino) triphenylamine (4,4', 4 "-Tris (N, N-diphenyl-amino) triphenylamine; NATA), 4 ,4',4"-tris(N-(naphthalene-1-yl)-N-phenyl-amino)triphenylamine(4,4',4"-Tris(N-(naphthalene-1-yl)-N -phenyl-amino)triphenylamine; 1T-NATA), 4,4',4"-tris(N-(naphthalen-2-yl)-N-phenyl-amino)triphenylamine(4,4',4"- Tris (N- (naphthalene-2-yl) -N-phenyl-amino) triphenylamine; 2T-NATA), copper phthalocyanine (CuPc), tris (4-carbazoyl-9yl-phenyl) amine (Tris ( 4-carbazoyl-9-yl-phenyl)amine; TCTA), N,N'-diphenyl-N,N'-bis(1-naphthyl)-1,1'-biphenyl-4,4"-diamine (N,N'-Diphenyl-N,N'-bis(1-naphthyl)-1,1'-biphenyl-4,4"-diamine; NPB; NPD), 1,4,5,8,9,11 -Hexaazatriphenylenehexacarbonitrile (1,4,5,8,9,11-Hexaazatriphenylenehexacarbonitrile, Dipyrazino[2,3-f:2'3'-h]quinoxaline-2,3,6,7,10 ,11-hexacarbonitrile; HAT-CN), 1,3,5-tris [4- (diphenylamino) phenyl] benzene (1,3,5-tris [4- (diphenylamino) phenyl] benzene; TDAPB), poly (3,4-ethylenedioxythiophene)polystyrene sulfonate (poly(3,4-ethylenedioxythiophene)polystyrene sulfonate; PEDOT/PSS) and/or N-(biphenyl-4-yl) -9,9-dimethyl-N- (4- (9-phenyl-9H-carbazol-3-yl) phenyl) -9H- fluorene-2-amine (N- (biphenyl-4-yl) -9, 9-dimethyl-N-(4-(9-phenyl-9H-carbazol-3-yl)phenyl)-9H-fluoren-2-amine) and the like. Depending on the characteristics of the organic light emitting diode 100, the hole injection layer 140 may be omitted.

The hole transport layer 150 is positioned adjacent to the light emitting material layer 160 between the first electrode 110 and the light emitting material layer 160 . In one exemplary embodiment, the hole transport layer 150 is N,N'-diphenyl-N,N'-bis(3-methylphenyl)-1,1'-biphenyl-4,4'-diamine (N ,N'-Diphenyl-N,N'-bis(3-methylphenyl)-1,1'-biphenyl-4,4'-diamine; TPD), NPB, 4,4'-bis(N-carbazolyl)- 1,1'-biphenyl (4,4'-bis (N-carbazolyl) -1,1'-biphenyl; CBP), poly [N, N'-bis (4-butylphenyl) -N, N'- Bis (phenyl) -benzidine] (Poly [N, N'-bis (4-butylpnehyl) -N, N'-bis (phenyl) -benzidine]; Poly-TPD), poly [(9,9-dioxylflu Orenyl-2,7-diyl)-co-(4,4'-(N-(4-sec-butylphenyl)diphenylamine))](Poly[(9,9-dioctylfluorenyl-2,7-diyl )-co-(4,4'-(N-(4-sec-butylphenyl)diphenylamine))], TFB), di-[4-(N,N-di-p-tolyl-amino)phenyl]cyclohexane (Di-[4-(N,N-di-p-tolyl-amino)-phenyl]cyclohexane; TAPC), N-(biphenyl-4-yl)-9,9-dimethyl-N-(4-( 9-phenyl-9H-carbazol-3-yl) phenyl) -9H-fluoren-2-amine (N- (biphenyl-4-yl) -9,9-dimethyl-N- (4- (9-phenyl -9H-carbazol-3-yl)phenyl)-9H-fluoren-2-amine) and/or N-(biphenyl-4-yl)-N-(4-(9-phenyl-9H-carbazole-3 -yl) phenyl) biphenyl) -4-amine (N- (biphenyl-4-yl) -N- (4- (9-phenyl-9H-carbazol-3-yl) phenyl) biphenyl-4-amine), etc. It may consist of a compound selected from the group consisting of, but the present invention is not limited thereto.

The light emitting material layer 160 may be formed by doping a host with a dopant. For example, the light emitting material layer 160 may have about 1 to 50% by weight of a dopant added to the host and may emit blue light.

In one exemplary embodiment, organic compounds represented by Chemical Formulas 1 to 5 may be used as a dopant of the light emitting material layer 160 . Meanwhile, the dopant, which is an organic compound represented by Chemical Formulas 1 to 5 used in the light emitting material layer 160, may be a dopant having delayed fluorescence characteristics.

As described above, the compound having delayed fluorescence is activated by heat or an electric field and has an intermediate energy state such as an ICT complex. Since both excitons having a singlet energy level and excitons having a triplet energy level are involved in light emission, the light emitting efficiency of the organic light emitting diode 100 can be improved.

The difference (ΔE _ST ) between the singlet energy level (S ₁ ) and the triplet energy level (T ₁ ) of the organic compounds represented by Chemical Formulas 1 to 5 may be 0.3 eV or less, for example, 0.05 to 0.3 eV. When the difference (ΔE _ST ) between the singlet energy level (S ₁ ) and the triplet energy level (T ₁ ) of organic compounds represented by Formulas 1 to 5 that can be used as delayed fluorescence dopants is 0.3 eV or less, these energy levels The quantum efficiency of the dopant may be improved while transitioning to an intermediate energy state and finally falling to the ground state. That is, the luminous efficiency may increase as ΔE _ST decreases, and when the difference between the singlet energy level (S ₁ ) and the triplet energy level (T ₁ ) of the dopant is 0.3 eV or less, the singlet state is generated by heat or an electric field. Excitons and triplet state excitons can transition to an intermediate ICT complex state (ΔE _ST ≤ 0.3).

Meanwhile, in order to implement delayed fluorescence, the host included in the light emitting material layer 160 should be able to induce excitons in the triplet state in the dopant to participate in light emission without quenching. 3 is a schematic diagram for explaining a correlation with an energy level of a delayed fluorescent compound when an organic compound according to an exemplary embodiment of the present invention is used as a host.

As shown in FIG. 3, the energy level of the host for realizing delayed fluorescence should be adjusted with the dopant. First, the triplet energy level of the host (T ₁ ^H ) must be higher than the triplet energy level of the dopant (T ₁ ^D ). If the triplet energy level of the host (T ₁ ^H ) is not sufficiently higher than the triplet energy level of the dopant (T ₁ ^D ), the triplet state excitons of the dopant cross over to the triplet energy level of the host (T ₁ ^H ). Since the exciton in the triplet state of the dopant does not contribute to light emission, since it disappears due to non-emission.

In addition, it is necessary to properly adjust the HOMO energy level and the LUMO energy level of the host and the dopant. For example, the difference between the highest occupied molecular orbital energy level of the host (HOMO ^H ) and the highest occupied molecular orbital energy level of the dopant (HOMO ^D ) (|HOMO ^H -HOMO ^D |) or the lowest unoccupied molecular orbital of the host It may be preferable that the difference between the energy level (LUMO ^H ) and the lowest unoccupied molecular orbital energy level (LUMO ^D ) of the dopant (|LUMO ^H -LUMO ^D |) is 0.5 eV or less, for example, 0.1 to 0.5 eV or less. there is. Accordingly, the charge transfer efficiency from the host to the dopant is improved, and finally, the luminous efficiency may be improved.

In one exemplary embodiment, the host of the light emitting material layer 160 is 9-(3-(9H-carbazol-9-yl)phenyl)-9H-carbazole-3-carbonitrile (9-(3- (9H-carbazol-9-yl)phenyl)-9H-carbazole-3-carbonitrile; mCP-CN), CBP, 3,3'-bis(N-carbazolyl)-1,1'-biphenyl (3, 3'-bis (N-carbazolyl) -1,1'-biphenyl; mCBP), 1,3-bis (carbazol-9-yl) benzene (1,3-Bis (carbazol-9-yl) benzene; MCP ), (Oxybis (2,1-phenylene)) bis (diphenylphosphine oxide) (Oxybis (2,1-phenylene)) bis (diphenylphosphine oxide; DPEPO), 2T-NATA, TCTA, 1,3, 5-tri[(3-pyridyl)-phen-3-yl]benzene (1,3,5-Tri[(3-pyridyl)-phen-3-yl]benzene; TmPyPB), 2,6-di( 9H-carbazol-9-yl)pyridine (2,6-Di(9H-carbazol-9-yl)pyridine; PYD-2Cz), 3', 5'-di(carbazol-9-yl)-[1 ,1'-biphenyl] -3,5-dicarbonitrile (3',5'-Di (carbazol-9-yl) - [1,1'-bipheyl] -3,5-dicarbonitrile; DCzTPA), 4 '-(9H-carbazol-9-yl)biphenyl-3,5-dicarbonitrile(4'-(9H-carbazol-9-yl)biphenyl-3,5-dicarbonitrile; pCzB-2CN), 3'-(9H- Carbazol-9-yl) biphenyl-3,5-dicarbonitrile (3'-(9H-carbazol-9-yl)biphenyl-3,5-dicarbonitrile; mCzB-2CN), 4-(3-(tri) Phenylen-2-yl) phenyl) dibenzo [b, d] thiophene (4- (3- (triphenylen-2-yl) phenyl) dibenzo [b, d] thiophene), 9- (4- (9H- Carbazol-9-yl) phenyl) -9H-3,9'-bicarbazole (9- (4- (9H-carbazol-9-yl) phenyl) -9H-3,9'-bicarbazole) and / or 9- (3- (9H-carbazol-9-yl) phenyl) -9H-3,9'-bicarbazole (9- (3- (9H-carbazol-9-yl) phenyl) -9H- 3,9'-bicarbazole) and the like, but the present invention is not limited thereto.

Referring back to FIG. 2 , an electron transport layer 170 and an electron injection layer 180 may be sequentially stacked between the light emitting material layer 160 and the second electrode 120 . A material constituting the electron transport layer 170 requires high electron mobility, and electrons are stably supplied to the light emitting material layer 160 through smooth electron transport.

In one exemplary embodiment, the electron transport layer 170 is oxadiazole, triazole, phenanthroline, benzoxazole, benzothiazole, benzimidazole , may be a derivative such as triazine. For example, the electron transport layer 170 is tris (8-hydroxyquinoline) aluminum (tris- (8-hydroxyquinoline aluminum; Alq ₃ ), 2-biphenyl-4-yl-5- (4-tert-butylphenyl ) -1,3,4-oxadiazole (2-biphenyl-4-yl-5- (4-t-butylphenyl) -1,3,4-oxadiazole; PBD), spiro-PBD, lithium quinolate ( lithium quinolate; Liq), 1,3,5-tris (N-phenylbenzimidazol-2-yl) benzene (1,3,5-Tris (N-phenylbenzimidazol-2-yl) benzene; TPBi), bis ( 2-methyl-8-quinolinolato-N1,O8)-(1,1'-biphenyl-4-olato)aluminum (Bis(2-methyl-8-quinolinolato-N1,O8)-(1, 1'-biphenyl-4-olato)aluminum; BAlq), 4,7-diphenyl-1,10-phenanthroline; Bphen), 2,9-bis( Naphthalen-2-yl) 4,7-diphenyl-1,10-phenanthroline (2,9-Bis (naphthalene-2-yl) 4,7-diphenyl-1,10-phenanthroline; NBphen), 2, 9-dimethyl-4,7-diphenyl-1,10-phenanthroline (2,9-Dimethyl-4,7-diphenyl-1,10-phenathroline; BCP), 3-(4-biphenyl)-4 -Phenyl-5-tert-butylphenyl-1,2,4-triazole (3-(4-Biphenyl)-4-phenyl-5-tert-butylphenyl-1,2,4-triazole; TAZ), 4- (Naphthalen-1-yl)-3,5-diphenyl-4H-1,2,4-triazole (4-(Naphthalen-1-yl)-3,5-diphenyl-4H-1,2,4- triazole; NTAZ), 1,3,5-Tri(p-pyrid-3-yl-phenyl)benzene; TpPyPB), 2 ,4,6-tris(3'-(pyridin-3-yl)biphenyl-3-yl)1,3,5-triazine(2,4,6-Tris(3'-(pyrid in-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)](Poly[9,9-bis(3'-((N,N-dimethyl)-N-ethylammonium)-propyl)-2,7-fluorene]-alt-2,7- (9,9-dioctylfluorene)]; PFNBr) and/or tris(phenylquinoxaline; TPQ), etc., but the present invention is not limited thereto.

The electron injection layer 180 is positioned between the second electrode 120 and the electron transport layer 170, and the life of the device can be improved by improving the characteristics of the second electrode 120. In one exemplary embodiment, as a material of the electron injection layer 180, an alkali halide-based material such as LiF, CsF, NaF, BaF ₂ , and/or lithium quinolate (Liq), lithium benzoate, sodium Organometallic materials such as stearate (sodium stearate) may be used, but the present invention is not limited thereto.

The organic light emitting diode 100 according to an exemplary embodiment of the present invention has a dopant, which is an organic compound represented by Chemical Formulas 1 to 5 having delayed fluorescence, in the light emitting material layer 160 constituting the organic light emitting layer 130, and there is. Since both excitons in the singlet energy state and the triplet energy state are involved in light emission, the light emission efficiency is improved.

Since the organic compounds represented by Formulas 1 to 5 coexist with the electron donor moiety and the electron acceptor moiety, the dipole moment increases, HOHO and LUMO are easily separated, and the dipole moment has a structure that can increase , has delayed fluorescence properties. In addition, since the three-dimensional structure between the indenofluorene ring having a rigid structure and the imidazole ring or thiazole ring is greatly restricted and energy loss is reduced during light emission, blue light emission with improved luminous efficiency and color purity can be implemented.

In addition, compared to the case of using a conventional phosphorescent material containing a heavy metal, the organic host included in the light emitting material layer (EML, 160) together with the organic compounds represented by Chemical Formulas 1 to 5 has a high triplet energy level. It does not have to have, and the band gap does not have to be wide. Therefore, problems caused by using an organic host having a wide energy bandgap, that is, charge injection and transport are delayed, and accordingly, the driving voltage of the light emitting diode 100 increases, power consumption increases, and device lifespan A deterioration of properties can be prevented.

Meanwhile, the organic light emitting diode according to the present invention may further include one or more exciton blocking layers. 4 is a schematic cross-sectional view of an organic light emitting diode to which a phosphorescent compound is applied according to a second exemplary embodiment of the present invention. As shown in FIG. 4, the organic light emitting diode 200 according to the second embodiment of the present invention includes a first electrode 210 and a second electrode 220 facing each other, and the first and second electrodes 210 , 220) and an organic light emitting layer 230 positioned between them.

In an exemplary embodiment, the organic light emitting layer 230 includes a hole injection layer 240, a hole transport layer 250, a light emitting material layer 260, an electron transport layer 270, and electron transport layer 270 sequentially stacked from the first electrode 210. An injection layer 280 is included. In addition, the organic light emitting layer 230 includes an electron blocking layer (EBL, 255) and/or a first exciton blocking layer positioned between the hole transport layer 250 and the light emitting material layer 260 and/or the light emitting material layer 260 ) and a hole blocking layer (HBL, 265) as a second exciton blocking layer located between the electron transport layer 270.

As described above, the first electrode 210 may be an anode and may be made of ITO, IZO, ITZO, SnO, ZnO, ICO, and AZO, which are conductive materials having a relatively high work function value. The second electrode 220 may be a cathode and may be made of Al, Mg, Ca, Ag, or an alloy or combination thereof, which is a conductive material having a relatively low work function value.

The hole injection layer 240 is positioned between the first electrode 210 and the hole transport layer 22 . The hole injection layer 240 is made of MTDATA, NATA, 1T-NATA, 2T-NATA, CuPc, TCTA, NPB (NPD), HAT-CN, TDAPB, PEDOT/PSS and/or N-(biphenyl-4-yl) -9,9-dimethyl-N-(4-(9-phenyl-9H-carbazol-3-yl)phenyl)-9H-fluoren-2-amine and the like.

The hole transport layer 250 is positioned adjacent to the light emitting material layer 260 between the first electrode 210 and the light emitting material layer 260 . Hole transport layer 250 is TPD, NPD (NPB), CBP, Poly-TPD, TFB, TAPC, N- (biphenyl-4-yl) -9,9-dimethyl-N- (4- (9-phenyl- 9H-carbazol-3-yl)phenyl)-9H-fluoren-2-amine and/or N-(biphenyl-4-yl)-N-(4-(9-phenyl-9H-carbazole-3 -yl) phenyl) biphenyl) -4-amine and other aromatic amine compounds.

The light emitting material layer 260 may be formed by doping a host with a dopant. For example, the light emitting material layer 260 may have a dopant added to the host in an amount of about 1 to 50% by weight, and may emit blue light. For example, organic compounds represented by Chemical Formulas 1 to 5 are used as dopants of the light emitting material layer 260, and mCP-CN, CBP, mCBP, MCP, DPEPO, 2T-NATA, TCTA, TmPyPB, PYD-2Cz, DCzTPA, pCzB-2CN, mCzB-2CN, 4-(3-(triphenylen-2-yl)phenyl)dibenzo[b,d]thiophene, 9-(4-(9H-carbazol-9-yl ) Phenyl) -9H-3,9'-bicarbazole and / or 9- (3- (9H-carbazol-9-yl) phenyl) -9H-3,9'-bicarbazole and the like compounds host can be used as

The electron transport layer 270 is positioned between the light emitting material layer 260 and the electron injection layer 280 . For example, the electron transport layer 270 may include oxadiazole, triazole, phenanthroline, benzoxazole, benzothiazole, benzimidazole, triazine, and the like. may be a derivative. For example, the electron transport layer 270 may be made of Alq ₃ , PBD, spiro-PBD, Liq, BAlq, Bphen, NBphen, BCP, TAZ, NTAZ, TpPyPB, TmPPPyTz, PFNBr, and/or TPQ, but The invention is not limited thereto.

The electron injection layer 280 is positioned between the second electrode 220 and the electron transport layer 270 . Alkali halide-based materials such as LiF, CsF, NaF, and BaF ₂ and/or organometallic materials such as Liq, lithium benzoate, and sodium stearate may be used as the material of the electron injection layer 280, but the present invention It is not limited.

On the other hand, when holes move through the light emitting material layer 260 to the second electrode 220 or when electrons pass through the light emitting material layer 260 and go to the first electrode 210, the lifetime and efficiency of the device may be reduced. can To prevent this, in the organic light emitting diode 200 according to the second exemplary embodiment of the present invention, at least one exciton blocking layer is positioned adjacent to the light emitting material layer 260 .

For example, the organic light emitting diode 200 according to the second embodiment of the present invention has an electron blocking layer capable of controlling or preventing the movement of electrons between the hole transport layer 250 and the light emitting material layer 260. layer, EBL, 255) is located.

For example, the electron blocking layer 255 is TCTA, tris [4- (diethylamino) phenyl] amine (tris [4- (diethylamino) phenyl] amine), N- (biphenyl-4-yl) -9, 9-dimethyl-N-(4-(9-phenyl-9H-carbazol-3-yl)phenyl)-9H-fluoren-2-amine, TAPC, MTDATA, mCP, mCBP, CuPC, N,N'- Bis[4-[bis(3-methylphenyl)amino]phenyl]-N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (N,N'-bis[4- [bis(3-methylphenyl)amino]phenyl]-N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine; DNTPD) and/or TDAPB.

In addition, a hole blocking layer 265 is positioned as a second exciton blocking layer between the light emitting material layer 260 and the electron transport layer 270 to prevent movement of holes between the light emitting material layer 260 and the electron transport layer 270 do. In one exemplary embodiment, as a material for the hole blocking layer, oxadiazole, triazole, phenanthroline, benzoxazole, and benzo that may be used in the electron transport layer 270 may be used. Derivatives such as benzothiazole, benzimidazole, and triazine may be used.

For example, the hole blocking layer 265 may be formed of BCP, BAlq, Alq3, PBD, or spiro- which has a lower HOMO (highest occupied molecular orbital) energy level compared to the material used in the light emitting material layer 260. PBD, Liq and/or bis-4,6-(3,5-di-3-pyridylphenyl)-2-methylpyrimidine (bis-4,6-(3,5-di-3-pyridylphenyl)- 2-methylpyrimidine; B3PYMPM) and combinations thereof.

The organic light emitting diode 200 according to the second embodiment of the present invention has a dopant, which is an organic compound represented by Chemical Formulas 1 to 5 having delayed fluorescence characteristics, in the light emitting material layer 160 . The organic compounds represented by Formulas 1 to 5 have a structure in which an electron donor moiety and an electron acceptor moiety coexist in one molecule to increase the dipole moment, easily separate HOHO and LUMO, and increase the dipole moment. Therefore, it has delayed fluorescence properties. In addition, the three-dimensional structures of the indenofluorene ring constituting the electron donor moiety and the imidazole ring or thiazole ring constituting the electron acceptor moiety are limited. Accordingly, when the organic compounds represented by Chemical Formulas 1 to 5 are used as dopants of the light emitting device, the light emitting efficiency is improved and the organic light emitting diode 200 having good color purity can be manufactured.

Since there is no need to use an organic host having high triplet energy and a wide bandgap, power consumption can be reduced by lowering the driving voltage of the light emitting diode 200 and lifespan of the device can be improved. In addition, since the organic light emitting diode 200 according to the second embodiment of the present invention includes at least one exciton blocking layer 255 or 265, the charge transport layers 250 or 270 adjacent to the light emitting material layer 260 By preventing light emission at the interface with the organic light emitting diode 200, the light emitting efficiency and lifetime of the organic light emitting diode 200 can be further improved.

The organic light emitting diode according to the present invention may be applied to an organic light emitting device such as an organic light emitting diode display device or a lighting device to which the above organic light emitting diode is applied. As an example, a display device to which the organic light emitting diode of the present invention is applied will be described. 5 is a schematic cross-sectional view of an organic light emitting diode display device according to an exemplary embodiment of the present invention.

As shown in FIG. 5 , the organic light emitting diode display 300 includes a driving thin film transistor Td as a driving element, a planarization layer 360 covering the driving thin film transistor Td, and a planarization layer 360 on and an organic light emitting diode 400 connected to the driving thin film transistor Td as a driving element. The driving thin film transistor (Td) includes a semiconductor layer 310, a gate electrode 330, a source electrode 352, and a drain electrode 354. In FIG. 3, the driving thin film has a coplanar structure. Indicates the transistor Td.

The substrate 302 may be a glass substrate, a thin flexible substrate, or a polymeric plastic substrate. For example, flexible substrates include polyimide (PI), polyethersulfone (PES), polyethylenenaphthalate (PEN), polyethylene terephthalate (PET) and polycarbonate (PC). It can be formed by any one of them. The driving thin film transistor (Td), which is a driving element, and the substrate 302 on which the organic light emitting diode 400 are positioned form an array substrate.

A semiconductor layer 310 is formed on the substrate 302 . For example, the semiconductor layer 310 may be made of an oxide semiconductor material. In this case, a light-shielding pattern (not shown) and a buffer layer (not shown) may be formed under the semiconductor layer 310, and the light-shielding pattern prevents light from entering the semiconductor layer 310 so that the semiconductor layer 310 is not exposed to light. prevent degradation by Alternatively, the semiconductor layer 310 may be made of polycrystalline silicon, and in this case, both edges of the semiconductor layer 310 may be doped with impurities.

A gate insulating film 320 made of an insulating material is formed on the entire surface of the substrate 302 on the semiconductor layer 310 . The gate insulating layer 320 may be formed of an inorganic insulating material such as silicon oxide (SiO ₂ ) or silicon nitride (SiNx).

A gate electrode 330 made of a conductive material such as metal is formed on the top of the gate insulating film 320 to correspond to the center of the semiconductor layer 310 . In addition, a gate wiring (not shown) and a first capacitor electrode (not shown) may be formed on the gate insulating layer 320 . The gate wiring may extend along the first direction, and the first capacitor electrode may be connected to the gate electrode 330 . Meanwhile, although the gate insulating film 320 is formed on the entire surface of the substrate 302 , the gate insulating film 320 may be patterned in the same shape as the gate electrode 330 .

An interlayer insulating film 340 made of an insulating material is formed on the entire surface of the substrate 302 above the gate electrode 330 . The interlayer insulating film 340 may be formed of an inorganic insulating material such as silicon oxide (SiO ₂ ) or silicon nitride (SiNx), or an organic insulating material such as benzocyclobutene or photo-acryl. there is.

The interlayer insulating film 340 has first and second semiconductor layer contact holes 342 and 344 exposing top surfaces of both sides of the semiconductor layer 310 . The first and second semiconductor layer contact holes 342 and 344 are spaced apart from the gate electrode 330 on both sides of the gate electrode 330 . Here, the first and second semiconductor layer contact holes 342 and 344 are also formed in the gate insulating layer 320 . In contrast, when the gate insulating film 320 is patterned in the same shape as the gate electrode 330, the first and second semiconductor layer contact holes 342 and 344 are formed only in the interlayer insulating film 340.

A source electrode 352 and a drain electrode 354 made of a conductive material such as metal are formed on the interlayer insulating film 340 . In addition, a data wire (not shown), a power supply wire (not shown), and a second capacitor electrode (not shown) may be formed on the interlayer insulating film 340 and extend along the second direction.

The source electrode 352 and the drain electrode 354 are spaced apart from each other with respect to the gate electrode 330, and both sides of the semiconductor layer 310 and each other through the first and second semiconductor layer contact holes 342 and 344, respectively. make contact Although not shown, the data line extends along the second direction and intersects the gate line to define a pixel area, and the power line supplying a high potential voltage is spaced apart from the data line. The second capacitor electrode is connected to the drain electrode 354 and overlaps the first capacitor electrode, so that the interlayer insulating film 340 between the first and second capacitor electrodes serves as a dielectric layer to form a storage capacitor.

Meanwhile, the semiconductor layer 310, the gate electrode 330, the source electrode 352, and the drain electrode 354 form a driving thin film transistor Td. The driving thin film transistor Td illustrated in FIG. 5 has a coplanar structure in which a gate electrode 330 , a source electrode 352 , and a drain electrode 354 are positioned on a semiconductor layer 310 . Alternatively, the driving thin film transistor Td may have an inverted staggered structure in which a gate electrode is positioned below the semiconductor layer and a source electrode and a drain electrode are positioned above the semiconductor layer. In this case, the semiconductor layer may be made of amorphous silicon.

In addition, a switching thin film transistor (not shown), which is a switching element having substantially the same structure as the driving thin film transistor Td, is further formed on the substrate 302 . The gate electrode 330 of the driving thin film transistor (Td) is connected to the drain electrode (not shown) of the switching thin film transistor (not shown), and the source electrode 352 of the driving thin film transistor (Td) is connected to a power wiring (not shown). Connected. In addition, the gate electrode (not shown) and the source electrode (not shown) of the switching thin film transistor (not shown) are respectively connected to the gate wiring and the data wiring.

Meanwhile, the organic light emitting diode display 300 may include a color filter (not shown) absorbing light generated by the organic light emitting diode 400 . For example, a color filter (not shown) may absorb red (R), green (G), blue (B), and white (W) light. In this case, red, green, and blue color filter patterns that absorb light may be separately formed for each pixel area, and each of these color filter patterns is an organic light emitting diode (OLED) that emits light of a wavelength band to be absorbed. 400) may be disposed to overlap each other with the organic light emitting layer 430. By adopting a color filter (not shown), the organic light emitting diode display 300 can implement full-color.

For example, when the organic light emitting diode display device 300 is a bottom emission type, a color filter (not shown) absorbing light may be positioned above the interlayer insulating layer 340 corresponding to the organic light emitting diode 400. . In an optional embodiment, when the organic light emitting diode display device 300 is a top emission type, the color filter may be positioned above the organic light emitting diode 400, that is, above the second electrode 420.

A planarization layer 360 is formed on the entire surface of the substrate 302 on the source electrode 352 and the drain electrode 354 . The planarization layer 360 has a flat upper surface and has a drain contact hole 362 exposing the drain electrode 354 of the driving thin film transistor Td. Here, the drain contact hole 362 is illustrated as being formed right above the second semiconductor layer contact hole 344, but may be formed spaced apart from the second semiconductor layer contact hole 344.

The light emitting diode 400 includes a first electrode 410 positioned on the planarization layer 360 and connected to the drain electrode 354 of the driving thin film transistor Td, and an organic layer sequentially stacked on the first electrode 410. A light emitting layer 430 and a second electrode 420 are included.

One electrode 410 is formed separately for each pixel area. The first electrode 410 may be an anode and may be made of a conductive material having a relatively high work function value. For example, the first electrode 410 may be made of a transparent conductive material such as ITO, IZO, ITZO, SnO, ZnO, ICO, and AZO.

Meanwhile, when the organic light emitting diode display 300 of the present invention is a top-emission type, a reflective electrode or a reflective layer may be further formed below the first electrode 310 . For example, the reflective electrode or the reflective layer may be made of an aluminum-palladium-copper (APC) alloy.

In addition, a bank layer 370 covering an edge of the first electrode 410 is formed on the planarization layer 360 . The bank layer 370 exposes the center of the first electrode 410 corresponding to the pixel area.

An organic emission layer 430 is formed on the first electrode 410 . In one exemplary embodiment, the organic light-emitting layer 430 may have a single-layer structure of light-emitting material layers. Alternatively, as shown in FIGS. 2 and/or 4 , the organic light emitting layer 430 includes a hole injection layer, a hole transport layer, an electron blocking layer, a light emitting material layer, a hole blocking layer, an electron transport layer, and/or an electron injection layer. It may also consist of a plurality of organic material layers.

A second electrode 420 is formed on the substrate 302 on which the organic light emitting layer 430 is formed. The second electrode 420 is located on the entire surface of the display area and is made of a conductive material having a relatively low work function value and can be used as a cathode. For example, the second electrode 420 is made of any one of aluminum (Al), magnesium (Mg), calcium (ca), silver (Ag), or an alloy or combination thereof such as an aluminum-magnesium alloy (AlMg). can

An encapsulation film 380 is formed on the second electrode 420 to prevent penetration of external moisture into the organic light emitting diode 400 . The encapsulation film 380 may have a stacked structure of a first inorganic insulating layer 382, an organic insulating layer 384, and a second inorganic insulating layer 386, but is not limited thereto.

As described above, the organic light emitting diode 400 is represented by Chemical Formulas 1 to 5 in the organic light emitting layer 430 and an organic compound having delayed fluorescence is used as a dopant to improve light emitting efficiency.

Organic compounds represented by Chemical Formulas 1 to 5 have delayed fluorescence characteristics because an electron donor moiety and an electron acceptor moiety coexist in one molecule. In addition, the three-dimensional structure of the indenofluorene ring constituting the electron donor moiety and the imidazole ring or thiazole ring constituting the electron acceptor moiety is limited. Accordingly, when the organic compounds represented by Chemical Formulas 1 to 5 are used as dopants of the light emitting device, the light emitting efficiency is improved and the organic light emitting diode 400 having good color purity can be manufactured. Since there is no need to use an organic host having high triplet energy and a wide bandgap, power consumption can be reduced by lowering the driving voltage of the light emitting diode 400 and the organic light emitting diode display device 300 including the same. can improve the lifespan of

Hereinafter, the present invention will be described through exemplary embodiments, but the present invention is not limited to the technical idea described in the following examples.

Synthesis Example 1: Synthesis of Compound 1

(1) Synthesis of 2-(4-bromophenyl)-1,4,5-triphenyl-1H-imidazole (A1)

In a 500 mL 2-neck flask, 4-Bromobenzaldehyde (5.00 g, 27.03 mmol), Aniline (12.58 g, 135.13 mmol), Benzil (1,2-diphenylethane-1,2-dione, 5.68 g, 27.03 mmol), Ammonium acetate (8.33 g, 108.10 mmol) and dissolved in 250 mL of acetic acid. Then stirred under reflux for 3 hours. After completion of the reaction, the precipitated solid is filtered and washed with acetic acid:water (1:1) solution. 9.15 g (yield: 75%) of white solid A1 was obtained.

(2) 1,4,5-triphenyl-2-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)-1H-imidazole (A-2) synthesis

500 mL 2-neck flask A-1 (5.00 g, 11.08 mmol), Bis (pinacolato) diboran (8.44 g, 33.23 mmol), Pd ₂ (dba) ₃ (Tris (dibenzylideneacetone) dipalladium (0), 0.30 g, 0.33 mmol), XPhos (2-Dicyclohexylphosphino-2',4'',6'-triisopropylbiphenyl, 0.32 g, 0.66 mmol), KOAc (Potassium acetate, 3.81 g, 38.77 mmol) and dissolve in 200 mL of 1,4-Dioxane. . Then stirred under reflux for 12 hours. After completion of the reaction, column with hexane: ethyl acetate (10: 1) to obtain 4.80 g of solid A-2 (yield: 88.07%).

(3) Synthesis of 8-bromo-6,6,12,12-tetramethyl-N,N-diphenyl-6,12-dihydroindeno[1,2-b]fluoren-2-amine (B-2)

In a 250 mL 2-neck flask, B-1 (5.00 g, 11.68 mmol), diphenyamine (2.17 g, 12.81 mmol), Pd ₂ (dba) ₃ (0.29 g, 0.32 mmol), potassium tert-butoxide (0.06 g, 0.32 mmol) mmol) and sodium tert-butoxide (2.05 g, 21.36 mmol) and dissolve in 200 mL of 1,4-Dioxane. Then, it was stirred under reflux for 12 hours. After completion of the reaction, column with hexane: ethyl acetate (10: 1) to obtain 4.0 g of solid B-2 (yield: 67.3%).

(4) 6,6,12,12-tetramethyl-N,N-diphenyl-8-(4-(1,4,5-triphenyl-1H-imidazol-2-yl)phenyl)-6,12-dihydroindeno[ Synthesis of 1,2-b]fluoren-2-amine (Compound 1)

B-2 (1.00 g, 1.80 mmol), A-2 (1.07 g, 2.16 mmol), K ₂ CO ₃ (1.24 g, 8.98 mmol), Pd(PPh ₃ ) ₄ (Tetrakis ( Add triphenylphosphine)palladium (0), 0.06 g, 0.05 mmol) and dissolve in 80 mL of a mixed solvent of THF: water (3:1). Then stirred under reflux for 12 hours. After completion of the reaction, column with MC: hexane to obtain 0.9 g (yield: 59.0%) of compound 1 as a solid.

Synthesis Example 2: Synthesis of Compound 2

(1) Synthesis of 4,5-diphenyl-2-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)thiazole (C-1)

In a 500 mL 2-neck flask, 2-(4-bromophenyl)-4,5-diphenylthiazole (3.30 g, 8.41 mmol), Bis(pinacolato)diboran (6.41 g, 25.24 mmol), Pd ₂ (dba) ₃ (0.23 g) , 0.25 mmol), XPhos (0.24 g, 0.50 mmol), and KOAc (2.89 g, 29.44 mmol) were added and dissolved in 100 mL of 1,4-Dioxane. Then, it was stirred under reflux for 12 hours. After completion of the reaction, column with hexane: ethyl acetate (10: 1) to obtain 2.72 g of solid C1 (yield: 73.5%).

(2)

8-(4-(4,5-diphenylthiazol-2-yl)phenyl)-6,6,12,12-tetramethyl-N,N-diphenyl-6,12-dihydroindeno[1,2-b]fluoren-2 -amine (compound 2) synthesis

In a 250 mL 2-neck flask, B-2 (1.00 g, 1.80 mmol), C-1 (1.07 g, 2.16 mmol), K ₂ CO ₃ (1.24 g, 8.98 mmol), Pd (PPh ₃ ) ₄ (0.06 g , 0.05 mmol) and dissolved in 80 mL of a THF:water (3:1) mixed solvent. Then stirred under reflux for 12 hours. After completion of the reaction, column with MC: hexane to obtain 0.95 g (yield: 67.0%) of the solid compound.

Example 1: Fabrication of Organic Light-Emitting Diode

An organic light emitting diode was manufactured by applying Compound 1 synthesized in Synthesis Example 1 as a dopant of the light emitting material layer. First, a 40 mm x 40 mm x 0.5 mm thick ITO (including reflector) electrode-attached glass substrate was ultrasonically cleaned with isopropyl alcohol, acetone, and DI water for 5 minutes, and then dried in an oven at 100 °C. After cleaning the substrate, it was treated with O ₂ plasma for 2 minutes in a vacuum state and transferred to a deposition chamber to deposit other layers thereon. Organic layers were deposited in the following order by evaporation from a heating boat under a vacuum of about 10 ⁻⁷ Torr.

Hole injection layer (HIL; HAT-CN, 7 nm), hole transport layer (HTL; NPB, 55 nm), electron blocking layer (EBL; mCBP, 10 nm), light emitting material layer (EML; 4-(3-(tree) Phenylen-2-yl) phenyl) dibenzo [b, d] thiophene is used as a host, compound 1 is doped 5% by weight, 25 nm), hole blocking layer (HBL; B3PYMPM, 10 nm), electron transport layer (ETL; TPBi, 20 nm), electron injection layer (EIL; LiF), cathode (Al).

After forming a capping layer (CPL), it was encapsulated with glass. After deposition of these layers, they were transferred from the deposition chamber into a dry box for film formation and subsequently encapsulated using UV curing epoxy and a moisture getter.

Example 2: Fabrication of Organic Light-Emitting Diode

An organic light emitting diode was manufactured by repeating the procedure of Example 1, except that Compound 2 synthesized in Synthesis Example 2 was used instead of Compound 1 as the dopant of the light emitting material layer.

Comparative Examples 1 and 2: Production of Organic Light-Emitting Diodes

An organic light emitting diode was manufactured by repeating the procedure of Example 1 except for using each of the materials represented by the following chemical formula in place of Compound 1 as the dopant of the light emitting material layer.

Experimental Example: Measurement of Light Emission Characteristics of Organic Light-Emitting Diodes

Physical properties were measured for the organic light emitting diodes manufactured in Examples 1 to 2 and Comparative Example 1-2, respectively. Each organic light emitting diode having an emission area of 9 mm 2 was connected to an external power source, and device characteristics were evaluated at room temperature using a current source (KEITHLEY) and a photometer (PR 650). The current efficiency (cd/A), power efficiency (lm/W), external quantum efficiency (EQE, %), and CIE color coordinate measurement results of each light emitting diode measured at a current density of 10 ㎃/㎠ are shown below. Table 1 shows.

Evaluating light emitting characteristics of light emitting diodes Sample cd/A lm/W EQE (%) CIEx CIEy Comparative Example 1 6.69 5.10 3.11 0.198 0.396 Comparative Example 2 6.10 4.93 2.79 0.211 0.394 Example 1 8.92 5.09 5.72 0.170 0.235 Example 2 11.67 7.39 6.94 0.170 0.263

As shown in Table 1, compared to the case where the organic compound of Comparative Example 1 was used as the dopant of the light emitting material layer, when the organic compound synthesized according to the present invention was used as the dopant of the light emitting material layer, the current efficiency was up to 74.4%. , the power efficiency was improved by up to 44.9%, and the external quantum efficiency by up to 123.2%. In addition, compared to the case where the organic compound of Comparative Example 2 was used as the dopant of the light emitting material layer, when the organic compound synthesized according to the present invention was used as the dopant of the light emitting material layer, the current efficiency was up to 91.3% and the power efficiency was up to 49.9%, and the external quantum efficiency was improved by up to 148.7%. In addition, as can be seen from the color coordinate measurement, compared to the organic compound of Comparative Example 1-2, the organic compound synthesized according to the present invention emits blue light of high color purity. As a result, by applying the organic compound of the present invention to the light emitting layer, the driving voltage can be significantly lowered, and an organic light emitting diode with good light emitting efficiency can be manufactured. Therefore, the organic light emitting diode to which the organic compound of the present invention is applied can be used for an organic light emitting diode display device and/or a lighting device.

In the above, the present invention has been described based on exemplary embodiments and examples of the present invention, but the present invention is not limited to the technical idea described in the above embodiments and examples. Rather, those skilled in the art to which the present invention pertains can easily make various modifications and changes based on the above-described embodiments and examples. However, it is clear from the appended claims that all of these modifications and changes fall within the scope of the present invention.

100, 200, 400: organic light emitting diode
110, 210, 410: first electrode 120, 220, 420: second electrode
130, 230, 430: organic light emitting layer 140, 240: hole injection layer
150, 250: hole transport layer 160, 260: light emitting material layer
170, 270: electron transport layer 180, 280: electron injection layer
255, 265: exciton blocking layer 300: organic light emitting diode display

Claims (14)

An organic compound represented by Formula 1 below.
Formula 1

(In Formula 1, R ₁ to R ₄ are each independently selected from the group consisting of hydrogen, heavy hydrogen, tritium, and C ₁ ~ C ₂₀ alkyl groups; R ₅ is represented by Formula 2 below; Ar ₁ and Ar ₂ are each independently unsubstituted or C ₁ ~C ₂₀ alkyl substituted C ₆ ~C ₃₀ homo aryl group)
Formula 2

(In Formula 2, R ₆ and R ₇ are each independently an unsubstituted or C ₁ ~ C ₂₀ alkyl-substituted C ₆ ~ C ₃₀ homoaryl group; X is S or NR ₈ , and R ₈ is unsubstituted or C ₁ ~ C ₂₀ alkyl substituted C ₆ ~ C ₃₀ homo aryl group; L ₁ is unsubstituted or C ₁ ~ C ₂₀ alkyl substituted C ₆ ~ C ₃₀ homo arylene group)
According to claim 1,
The organic compound includes an organic compound represented by Formula 3 below.
Formula 3

(In Formula 3, R ₁ to R ₄ are each the same as defined in Formula 1; R ₉ and R ₁₀ are each independently selected from the group consisting of hydrogen, deuterium, tritium, and C ₁ to C ₂₀ alkyl; R ₁₁ is represented by Formula 4 below)
formula 4

(X in Formula 4 is the same as defined in Formula 2)
According to claim 1,
The organic compound is any organic compound represented by Formula 5 below.
Formula 5

a first electrode and a second electrode facing each other;
An organic light emitting layer positioned between the first electrode and the second electrode,
The organic light emitting layer is an organic light emitting diode including an organic compound represented by Formula 1 below.
Formula 1

(In Formula 1, R ₁ to R ₄ are each independently selected from the group consisting of hydrogen, heavy hydrogen, tritium, and C ₁ ~ C ₂₀ alkyl groups; R ₅ is represented by Formula 2 below; Ar ₁ and Ar ₂ are each independently unsubstituted or C ₁ ~C ₂₀ alkyl substituted C ₆ ~C ₃₀ homo aryl group)
Formula 2

(In Formula 2, R ₆ and R ₇ are each independently an unsubstituted or C ₁ ~ C ₂₀ alkyl-substituted C ₆ ~ C ₃₀ homoaryl group; X is S or NR ₈ , and R ₈ is unsubstituted or C ₁ ~ C ₂₀ alkyl substituted C ₆ ~ C ₃₀ homo aryl group; L ₁ is unsubstituted or C ₁ ~ C ₂₀ alkyl substituted C ₆ ~ C ₃₀ homo arylene group)
According to claim 4,
The organic light emitting diode including an organic compound represented by the following formula (3).
Formula 3

(In Formula 3, R ₁ to R ₄ are each the same as defined in Formula 1; R ₉ and R ₁₀ are each independently selected from the group consisting of hydrogen, deuterium, tritium, and C ₁ to C ₂₀ alkyl; R ₁₁ is represented by Formula 4 below)
formula 4

(X in Formula 4 is the same as defined in Formula 2)
According to claim 4,
The organic compound is any one organic compound represented by the following formula (5) light emitting diode.
Formula 5

According to claim 4,
The organic compound is an organic light emitting diode used as a dopant of a light emitting material layer.
According to claim 7,
The light emitting material layer further comprises a host organic light emitting diode.
According to claim 8,
The difference between the highest occupied molecular orbital energy level (HOMO ^H ) of the host and the highest occupied molecular orbital energy level (HOMO ^D ) of the dopant (|HOMO ^H -HOMO ^D |) or the lowest unoccupied molecular orbital of the host An organic light-emitting diode having a difference (|LUMO ^H -LUMO ^D |) between an energy level (LUMO ^H ) and a lowest unoccupied molecular orbital energy level (LUMO ^D ) of the dopant is 0.5 eV or less.
According to claim 4,
A difference (ΔE _ST ) between a singlet energy level (S ₁ ) and a triplet energy level (T ₁ ) of the organic compound is 0.3 eV or less.
Board;
Located on the substrate, the organic light emitting diode according to any one of claims 4 to 10; and
A driving element located on the substrate and connected to the first electrode of the organic light emitting diode
An organic light emitting device comprising a.
According to claim 11,
The organic light emitting device includes an organic light emitting diode display device. delete delete

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