KR102413121B1 - Organic compounds, organic light emitting diode and orgnic light emitting device having the compounds - Google Patents

Abstract

The present invention relates to organic compounds having at least one aromatic ring linked to the indolocarbazole moiety, either directly or via a linker. The organic compound according to the present invention has an indolocarbazole moiety consisting of five rings having a large steric hindrance with an adjacent moiety, and thus has a strong structure. In addition, the organic compound of the present invention has an indolocarbazole moiety and/or a cyano group with excellent electron withdrawing properties in an adjacent aromatic ring, so that the organic compound has a wide band gap and triplet energy is not lowered. and high-purity blue shifting is possible. By applying the organic compound of the present invention as a host to the light emitting device, it is possible to lower the driving voltage of the light emitting device and improve the luminous efficiency. In addition, the organic compound of the present invention can be applied to an organic light emitting diode, an organic light emitting device, etc. capable of emitting light with high purity blue.

Description

Organic compound, organic light emitting diode and organic light emitting device including same

The present invention relates to an organic compound, and more particularly, to an organic compound applicable to an organic material layer of a light emitting diode, an organic light emitting diode including the same, and an organic light emitting device.

As one of the currently widely used flat panel display devices, the technology of an organic light emitting diode device, also called an organic electroluminescent device (OELD), is rapidly developing.

Organic light emitting diodes (OLEDs) are formed of a thin organic thin film within 2000 Å, and images can be implemented in a single direction or in both directions depending on the configuration of an electrode used. In addition, since the organic light emitting diode display device can be formed on a flexible transparent substrate such as plastic, it is easy to implement a flexible or foldable display device. In addition, the organic light emitting diode display device can be driven at a low voltage and has excellent color purity, which has great advantages compared to a liquid crystal display device (LCD).

The 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, which are in an unstable energy state, and then in a stable ground state ( It returns to the ground state and emits light.

The actual efficiency characteristics of the OLED device are finally determined by the external quantum efficiency, which measures the amount of light emitted to the outside. The 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.

(η _int is the internal quantum efficiency (IQE); г is the charge balance factor; Φ is the radial quantum efficiency; η _out-coupling is the out-coupling efficiency) efficiency)

The internal quantum efficiency (η _int ) is the rate at which generated excitons are converted to the form of light. Triplet excitons in the form of (singlet exciton) and unpaired spin are generated at a ratio of 1:3. In a fluorescent material, only singlet excitons participate in luminescence, and the remaining 75% of triplet excitons do not participate in luminescence. As such, in the case of a typical fluorescent material that has a singlet and triplet generation ratio of 1:3 in an OLED device and cannot emit triplet excitons, the internal quantum efficiency (η _int ) is only 0.25 at most.

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

Light-extraction efficiency (η _out - _coupling ) is the ratio of light extracted to the outside among the light emitted from the light-emitting material. In general, when a thin film is formed by thermal evaporation of an isotropic light emitting material, individual light emitting molecules do not have a certain direction and exist in a disordered state. In such a random orientation state, when no special light extraction technique is applied, the light-extraction efficiency is in the range of 0.2 to 0.3. Therefore, when the four factors shown in Equation 1 are combined, the maximum luminous efficiency of the organic light emitting diode using the fluorescent material is only 5 to 7.5%.

In order to solve the low external quantum efficiency of fluorescent materials, phosphorescent materials have been developed. In the case of phosphorescent materials, most singlet excitons are transitioned to the triplet state through intersystem crossing (ISC), and the energy of the triplet state is lowered by strong spin-orbit coupling by heavy metals. state transition is possible. As such, phosphorescent materials have a light-emitting mechanism that converts both singlet energy and triplet energy into light. Therefore, the phosphorescent material can implement an external quantum efficiency of up to 20 to 30%.

However, metal complexes commonly used as phosphorescent materials are expensive and have a very short lifespan, which limits their commercialization. In particular, in the case of a blue phosphor, the color purity is difficult to apply to high-definition displays, and the lifespan also falls far short of the commercialization level, so it is not applied to commercialized OLED panels.

In addition, the blue phosphorescent host material must be higher than the triplet energy of the phosphorescent dopant material to prevent the triplet energy of the blue phosphorescent dopant from being transferred to the host. However, since the triplet energy of the organic aromatic compound is rapidly lowered as the conjugation increases or the fused ring is fused, organic materials that can be used as a blue phosphorescent host are extremely limited. Moreover, conventional blue phosphorescent hosts are designed to have a bandgap of 3.5 to 4.5 eV or more in order to have high triplet energy. Since the host material having an excessively wide bandgap does not smoothly inject and transport charges, a high driving voltage is required, which may adversely affect the lifetime characteristics of the device.

Accordingly, there is a demand for continuous development of organic compounds having excellent luminous efficiency and low voltage required to drive devices, light emitting diodes and light emitting devices to which the organic compounds are applied.

An object of the present invention is to provide an organic compound having a wide bandgap and good color purity.

Another object of the present invention is to provide an organic light emitting diode and an organic light emitting device having a low driving voltage and capable of implementing improved luminous efficiency.

According to one aspect of the present invention, the present invention provides an organic compound in which at least one aromatic moiety is linked directly or through a linker to an indolocarbazole moiety substituted with a cyano group (-CN). do. For example, the organic compound may be represented by the following formula (1).

Formula 1

(In Formula 1, R ₁ and R ₂ are each independently a hydrogen atom, a deuterium atom, a tritium atom, an unsubstituted or substituted C ₅ ~ C ₃₀ aryl group, or an unsubstituted or substituted C ₄ ~ C ₃₀ heteroaryl group, and , at least one of R ₁ and R ² is an unsubstituted or substituted C ₅ -C ₃₀ aryl group or an unsubstituted or substituted C ₄ -C ₃₀ heteroaryl group; L ₁ and L ₂ are each independently unsubstituted or substituted a C5~ C30 arylene group or an unsubstituted or substituted C4~ C30 hetero arylene group; a and b are each 0 or 1)

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

For example, the organic compound may be used as a host of the light emitting material layer.

The organic compounds of the present invention comprise at least one aromatic ring moiety linked directly or via a linker to an indolocarbazole moiety. Since the steric hindrance between the indolocarbazole moiety consisting of five rings and the adjacent aromatic ring moiety increases, the three-dimensional conformation of the organic compound of the present invention is limited, so that the The organic compound has a rigid structure and has excellent thermal stability. In addition, it has a cyano group (-CN) having excellent electron withdrawing properties in the indolocarbazole moiety. Accordingly, the organic compound according to the present invention has a wide band gap and high triplet energy, as well as a high purity blue shift (blue shift) is facilitated.

Therefore, by using the organic compound of the present invention as a host of the organic light emitting layer constituting the organic light emitting diode and using the compound showing delayed fluorescence characteristics as a dopant, the luminous efficiency is improved and stable driving characteristics (low driving voltage) can be realized. , an organic light emitting diode capable of emitting high-purity blue light and an organic light emitting device can be implemented.

1 is a schematic diagram for explaining the light emission mechanism of a delayed fluorescent compound used together with an organic compound according to an exemplary embodiment of the present invention.
2 is a schematic diagram for explaining the energy level with a delayed fluorescent compound when an organic compound according to an exemplary embodiment of the present invention is used as a host.
3 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.
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 a device having 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.
6 to 9 are graphs showing NMR analysis results of organic compounds synthesized according to an exemplary embodiment of the present invention, respectively.

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

[Organic compound]

The organic compound according to the present invention has a structure in which at least one aromatic ring is connected directly or through a linker to an indolocarbazole moiety substituted with a cyano group (-CN). The organic compound according to the present invention may be represented by the following formula (1).

Formula 1

(In Formula 1, R ₁ and R ₂ are each independently a hydrogen atom, a deuterium atom, a tritium atom, an unsubstituted or substituted C ₅ ~ C ₃₀ aryl group, or an unsubstituted or substituted C ₄ ~ C ₃₀ heteroaryl group, and , at least one of R ₁ and R ² is an unsubstituted or substituted C ₅ -C ₃₀ aryl group or an unsubstituted or substituted C ₄ -C ₃₀ heteroaryl group; L ₁ and L ₂ are each independently unsubstituted or substituted a C5~ C30 arylene group or an unsubstituted or substituted C4~ C30 hetero arylene group; a and b are each 0 or 1)

As used herein, 'unsubstituted' or 'unsubstituted' means that a hydrogen atom is substituted, and in this case, the hydrogen atom includes light hydrogen, deuterium and tritium.

In the present specification, the substituent in 'substituted' is, for example, an unsubstituted or halogen-substituted C1-C20 alkyl group, unsubstituted or halogen-substituted C1-C20 alkoxy group, halogen, cyano group, -CF ₃ , hydroxyl Group, carboxyl group, carbonyl group, amine group, C1-C10 alkyl-substituted amine group, C5-C30 aryl-substituted amine group, C4-C30 heteroaryl-substituted amine group, nitro group, hydrazyl group, sulfonic acid group, C1- C20 alkyl silyl group, C1~ C20 alkoxy silyl group, C3~ C30 cycloalkyl silyl group, C5~ C30 aryl silyl group, C4~ C30 heteroaryl silyl group, C5~ C30 aryl group, C4~ C30 heteroaryl group, etc. However, the present invention is not limited thereto. For example, when R ₂ and/or R ₂ in Formula 1 is substituted with an alkyl group, the alkyl group may be a straight or branched C ₁ to C ₂₀ , preferably a C ₁ to C ₁₀ alkyl group.

In the present specification, 'heteroaromatic ring', 'heterocycloalkylene group', 'heteroarylene group', 'heteroarylalkylene group', 'heteroaryloxyylene group', 'heterocycloalkyl group', 'heteroaryl group', ' The term 'hetero' used in 'heteroarylalkyl group', 'heteroaryloxyl group', 'heteroarylamine group', etc. is one or more of the carbon atoms constituting these aromatic or alicyclic rings, for example, For example, it means that 1 to 5 carbon atoms are substituted with one or more heteroatoms selected from the group consisting of N, O, S and combinations thereof.

In one exemplary embodiment, when R ₁ and/or R ₂ are unsubstituted or substituted C ₅ -C ₃₀ is an aryl group, R ₁ and/or R ₂ are each independently an unsubstituted or substituted phenyl group, bi Phenyl group, terphenyl group, naphthyl group, anthracenyl group, pentalenyl group, indenyl group, indenoindenyl group, heptalenyl group, biphenylenyl group, indacenyl group, phenalenyl group, phenanthrenyl group, benzophenanthrenyl group, Dibenzophenanthrenyl group, azulenyl group, pyrenyl group, fluoranthenyl group, triphenylenyl group, chrysenyl group, tetraphenyl group, tetracenyl group, pleidaenyl group, phisenyl group, pentaphenyl group, pentacenyl group , a fluorenyl group, an indenofluorenyl group or an uncondensed or fused aryl group such as a spiro fluorenyl group.

In an optional embodiment, when R ₁ and/or R ₂ is an unsubstituted or substituted C ₄ -C ₃₀ heteroaryl group, R ₁ and/or R ₂ are each independently an unsubstituted or substituted pyrrolyl group, pyridi Nyl group, pyrimidinyl group, pyrazinyl group, pyridazinyl group, triazinyl group, tetrazinyl group, imidazolyl group, pyrazolyl group, indolyl group, isoindoleyl group, indazolyl group, indolizinyl group, pyrrolizinyl group Group, carbazolyl group, benzocarbazolyl group, dibenzocarbazolyl group, indolocarbazolyl group, indenocarbazolyl group, benzofurocarbazolyl group, benzothienocarbazolyl group, quinolinyl group, isoquinoly Nyl group, phthalazinyl group, quinoxalinyl group, cinolinyl group, quinazolinyl group, quinozolinyl group, quinolinyl group, purinyl group, phthalazinyl group, quinoxalinyl group, benzoquinolinyl group, benzoisoquinolinyl group , benzoquinazolinyl group, benzoquinoxalinyl group, acridinyl group, phenanthrolinyl group, perimidinyl group, phenanthridinyl group, pteridinyl group, cinnolinyl group, naphtharidinyl group, furanyl group, pyranyl group, oxazinyl group group, oxazolyl group, oxadiazolyl group, triazolyl group, dioxynyl group, benzofuranyl group, dibenzofuranyl group, thiopyranyl group, xanthenyl group, chromenyl group, isochromenyl group, thioazinyl group, Thiophenyl group, benzothiophenyl group, dibenzothiophenyl group, difuropyrazinyl group, benzofurodibenzofuranyl group, benzothienobenzothiophenyl group, benzothienodibenzothiophenyl group, benzothienobenzofuranyl group, benzothienodibenzo It may be an uncondensed or condensed heteroaryl group such as a furanyl group or an N-substituted spiro fluorenyl group.

Meanwhile, in one non-limiting embodiment, L ₁ and/or L ₂ as a linker (linking group) in Formula 1 may each independently be an unsubstituted or substituted aromatic linking group.

For example, when L ₁ and/or L ₂ is an unsubstituted or substituted C ₅ ~C ₃₀ arylene group, L ₁ and/or L ₂ are each independently a substituted or unsubstituted phenylene group (phenylene), bi Phenylene group (biphenylene), terphenylene group (terphenylene), tetraphenylene group (tetraphenylene), indenylene group (indenylene), naphthylene group (naphthylene), azulenylene group (azulenylene), indacenylene group (indacenylene), acetonitrile A naphthylene group, a fluorenylene group, a spiro-fluorenylene group, a phenalenylene group, a phenanthrenylene group, an anthracenylene group, a fluoranthrenylene group (fluoranthrenylene), triphenylenylene, pyrenylene, chrysenylene, naphthacenylene, picenylene, perylenylene, pentaphenyl It may be selected from the group consisting of a pentaphenylene group and a hexacenylene group.

In another optional embodiment, when L ₁ and/or L ₂ is an unsubstituted or substituted C ₄ -C ₃₀ hetero arylene group, L ₁ and/or L ₂ are each independently a substituted or unsubstituted pyrrolylene group. (pyrrolylene), imidazolylene, pyrazolylene, pyridinylene, pyrazinylene, pyrimidinylene, pyridazinylene, iso Indolylene group, indolylene group, indazolylene group, purinylene group (purinylene), quinolinylene group (quinolinylene), isoquinolinylene group (isoquinolinylene), benzoquinolinylene group (benzoquinolinylene), phthalazinylene, naphthyridinylene, quinoxalinylene, quinazolinylene, benzoquinolinylene, benzoisoquinolinylene, benzo Quinazolinylene group, benzoquinoxalinylene group, cinnolinylene group, phenanthridinylene group, acridinylene group, phenanthrolinylene group, phenazinylene group, A benzoxazolylene group, a benzimidazolylene group, a furanylene group, a benzofuranylene group, a thiophenylene group, a benzothiophenylene group, a thiazolylene group (thiazolylene), isothiazolylene, benzothiazolylene, isoxazolylene, oxazolylene, triazolylene, te Trazolylene group, oxadiazolylene group, triazinylene group, benzofuranylene group, dibenzofuranylene group, benzofurodibenzofuranylene group, benzothienobenzofuranylene group, benzo Thienodibenzofuranylene group, benzothiophenylene group, dibenzothiophenylene group (dibenzothiophenylene), benzothienobenzothiophenylene group, benzothienodibenzothiophenylene group, carbazolylene group, benzocarbazolylene group, dibenzocarbazolyl Rene group, indolocarbazolylene group, indenocarbazolylene group, benzofurocarbazolylene group, benzothienocarbazolylene group, imidazopyrimidinylene group and imidazopyridinylene group may be selected from the group.

In one exemplary embodiment, when the number of aromatic rings constituting L ₁ and/or L ₂ increases, the conjugated structure in the entire organic compound becomes too long, so that the band gap of the organic compound can be excessively reduced. have. Therefore, preferably, the number of aromatic rings constituting L ₁ is 1 to 2, more preferably 1. In addition, with respect to hole or electron injection and transport properties, L ₁ and / or L ₂ Each may be a 5-membered ring (5-membered ring) to a 7-membered ring (7-membered ring), in particular 6- It may be preferable to be a 6-membered ring. For example, L ₁ and/or L ₂ is an unsubstituted or substituted phenylene group, a biphenylene group, a pyrrolylene group, an imidazolylene group, a pyrazolylene group, a pyridinylene group, a pyrazinylene group, a pyrimidinylene group, It may be a pyridazinylene group, a furanylene group, or a thiophenylene group.

The organic compound represented by Formula 1 can function as an electron donor, has an indolocarbazole moiety substituted with a cyano group (-CN), and has at least one aromatic ring moiety either directly or through a linker. is linked to an indolocarbazole moiety. Since the steric hindrance of the indolocarbazole moiety consisting of five aromatic rings is large, the organic compound of the present invention synthesized by the indolocarbazole moiety forming a chemical bond with the aromatic ring moiety 3 The dimensional conformation is limited. Accordingly, the organic compound according to the present invention has a rigid structure, thereby improving thermal stability. In addition, since the organic compound according to the present invention has at least one cyano group (-CN), the organic compound according to the present invention has a wide bandgap and high triplet energy, as well as a blue shift. becomes easier Therefore, the organic compound according to the present invention can be used as a host of the organic light emitting layer constituting the organic light emitting diode, and in particular can be applied to a light emitting material layer using a so-called delayed fluorescence compound as a dopant. Explain.

1 is a schematic diagram for explaining the light emission mechanism of a delayed fluorescent compound used together with an organic compound according to an exemplary embodiment of the present invention. 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 exceeding the maximum luminous efficiency in the material.

That is, in the delayed fluorescent compound, triplet excitons are activated by heat or electric field generated when the device is driven, and the triplet excitons also participate in light emission. In general, delayed fluorescent compounds have both an electron donor moiety and an electron acceptor moiety, so that an intramolecular charge transfer (ICT) state is possible. When a delayed fluorescent compound capable of an ICT state is used as a dopant, an exciton having a singlet energy level (S ₁ ) and an exciton having a triplet energy level (T ₁ ) in the delayed fluorescent compound move to the ICT state, which is an intermediate state, Transition to the ground state (S ₀ ) (S ₁ →ICT←T ₁ ), excitons having a singlet energy level (S ₁ ) and excitons having a triplet energy level (T ₁ ) participate in light emission Therefore, the internal quantum efficiency is improved, and thus the luminous efficiency is improved.

Conventionally, in fluorescent materials, the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) are spread throughout the molecule, so that a difference between a singlet state and a triplet state is present. Interchangeability is not possible (selection rule). However, since the compound having the ICT state has little overlap of HOMO and LUMO orbitals, the interaction between the orbital in the HOMO state and the orbital in the LUMO state is small. Therefore, the change in the spin state 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, in the delayed fluorescent compound, since the electron acceptor moiety and the electron donor moiety are spaced apart from each other in the molecule, an intramolecular dipole moment is present in a highly polarized state. When the dipole moment is polarized, the interaction between the orbitals of the HOMO and LUMO states becomes smaller, the transition from the triplet state and the singlet state to the intermediate state (ICT) becomes possible, and the singlet energy level (S ₁ ) exciton as well as the and triplet energy level (T ₁ ) excitons all participate in light emission. That is, when the light emitting device is driven, an exciton having a singlet energy level (S ₁ ) of 25% and an exciton having a triplet energy level (T ₁ ) of 75% transition 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 becomes 100% theoretically.

A dopant and a host for implementing delayed fluorescence need to have the following characteristics. The delayed fluorescence dopant has both an electron donor moiety and an electron acceptor moiety in one molecule, so it should be possible to implement ICT. The delayed fluorescence dopant is usually in the form of an ICT complex, and has an electron donor moiety and an electron acceptor moiety in one molecule at the same time, so that electron transfer occurs easily within the molecule. That is, in the ICT complex, under certain conditions, one electron from the electron donor moiety moves to the electron acceptor moiety, and the separation of charges occurs in the molecule. In addition, in order for energy transition to occur in both the triplet state and the singlet state, the difference (ΔE _ST ) between the singlet energy level (S1) and the triplet energy level (T1) of the dopant capable of implementing delayed fluorescence is 0.3 eV or less. , for example from 0.05 to 0.3 eV. In this way, when room temperature level thermal energy is applied to a compound with a low ΔE _ST , a reverse intersystem crossing (RISC) occurs from the triplet state to a higher energy singlet state, and the singlet state returns to the ground state. can be transferred

On the other hand, the host for implementing delayed fluorescence must be able to induce the exciton in the triplet state in the dopant to participate in light emission without quenching (non-luminescence quenching). 2 is a schematic diagram for explaining the energy level with 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. 2 , the energy level of the host to implement delayed fluorescence must be adjusted with the dopant. First, the excited-state triplet energy level (T _1h ) of the host must be higher than the excited-state triplet energy level (T _1d ) of the delayed fluorescent dopant. If the excited-state triplet energy level (T _1h ) of the host is not sufficiently higher than the energy of the excited-state triplet energy level (T _1d ) of the delayed fluorescent dopant, then the excited-state triplet energy level (T _1d ) of the delayed fluorescent dopant triplet of delayed fluorescent dopant, because a reverse-charge transfer occurs in the exciton of the host to the excited state triplet energy level (T _1h ), and triplet exciton non-luminescent annihilation in the host where the triplet exciton cannot emit light State excitons do not contribute to luminescence.

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

In addition, in order to secure the life of the device, the host must have a rigid structure. Since the organic compound represented by Formula 1 has an indolocarbazole moiety having a large steric hindrance as it consists of five rings, the three-dimensional structure is limited when combined with an adjacent aromatic ring. In the organic compound represented by Formula 1, the number of three-dimensional three-dimensional structures that a molecule can have can be minimized, so that it is structurally robust and has excellent thermal stability. Because the number of three-dimensional three-dimensional structures is limited and the emission spectrum can be limited to a specific range, high color purity can be realized, and stable driving (ie, low driving voltage) of the light emitting device can be implemented because of excellent thermal stability.

In addition, a cyano group having excellent electron withdrawing properties is introduced into the indolocarbazole moiety. Therefore, the organic compound represented by Chemical Formula 1 has a wide band gap as well as a high triplet energy level (T _1h ) in an excited state, so it is suitable for use as a host of the organic light emitting layer. That is, when the organic compound according to the present invention is used as a host of the organic light emitting layer, excitons of the excited state triplet energy level (T _1d ) of the delayed fluorescent dopant are reverse-charged to the triplet energy level (T _1h ) of the host. This is suppressed and the non-luminescence extinction of triplet excitons in the host is suppressed, while the triplet state excitons of the delayed fluorescence dopant all contribute to luminescence, and the luminous efficiency can be improved. In addition, by introducing at least one cyano group, it is possible to implement a blue shift (blue shift) due to excellent color purity.

In one exemplary embodiment, the organic compound according to the present invention includes a compound represented by the following formula (2).

Formula 2

(In Formula 2, a and b are each the same as defined in Formula 1; R ₃ and R ₄ are each independently an unsubstituted or substituted C4~ C30 heteroaryl group; L ₃ and L ₄ are each independently unsubstituted or a substituted C4~ C30 hetero arylene group)

,

,

,

또는

일 수 있다. 한편, L₃ 및/또는 L₄는 각각 5-원자 고리(5-membered ring) 내지 7-원자 고리(7-membered ring)일 수 있으며, 특히 6-원자 고리(6-membered ring)인 것이 바람직할 수 있다. 예를 들어, L₃ 및/또는 L₄는 치환되지 않거나 치환된 페닐렌기, 바이페닐렌기일 수 있지만, 본 발명이 이에 한정되는 것은 아니다. According to one exemplary embodiment, in Formula 2, R ₃ and/or R ₄ are each independently unsubstituted, or a cyano group, a C ₁ to C ₂₀ alkyl group, a C ₅ to C ₃₀ aryl group, and/or a C ₄ to It may be a carbazoyl group, an acridyl group, a dihydroacridyl group, a furobipyridyl group, a fluorenyl group, or a xanthenyl group substituted with a C ₃₀ heteroaryl group, but the present invention is not limited thereto. For example, R ₃ and/or R ₄ are each independently

,

,

,

or

can be On the other hand, L ₃ and/or L ₄ may each be a 5-membered ring to a 7-membered ring, particularly preferably a 6-membered ring. can do. For example, L ₃ and/or L ₄ may be an unsubstituted or substituted phenylene group or a biphenylene group, but the present invention is not limited thereto.

More specifically, the organic compound according to the present invention may be any one compound represented by the following formula (3).

Formula 3

Since the organic compound represented by Formula 2 or Formula 3 has a steric hindrance when combined with other moieties, it has an indolocarbazole moiety having a limited three-dimensional conformation and is structurally robust. Since the three-dimensional structure is limited, when the organic compound of the present invention is used as a light emitting material, stable driving is possible at a low voltage, and energy can be efficiently transferred to the dopant without loss of energy during the light emission process. In addition, since the cyano group is substituted in the indolocarbazole moiety, the energy band gap and the triplet energy level of the excited state (T _1h ) do not decrease, so that the luminous efficiency is improved, and excellent color purity can be realized while the blue transition is made. . That is, when the organic compound of Chemical Formula 2 or Chemical Formula 3 is used as a host of the light emitting material layer, energy can be efficiently transferred to the dopant, so that the luminous efficiency of the light emitting device to which the organic compound of the present invention is applied can be improved. In addition, due to thermal stability, it is possible to stably drive the light emitting device at a low voltage and realize a light emitting device with excellent color purity.

[Organic light emitting diode and organic light emitting diode display device]

As described above, the organic compound represented by Chemical Formulas 1 to 3 is used as a light emitting material in the organic light emitting layer constituting the organic light emitting diode, and thus a light emitting device having good color purity, luminous efficiency and low voltage driving can be realized. . This will be described. 3 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. 3 , 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. In an exemplary embodiment, the organic light emitting layer 130 is a hole injection layer (HIL, 140), a hole transfer layer (HTL, 150), which are sequentially stacked from the first electrode 110, a light emitting material and 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 for 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, a transparent conductive oxide (TCO). For example, the first electrode 110 may include 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) have.

The second electrode 120 may be a cathode for supplying electrons to the light emitting material layer 160 . The second electrode 120 has a reflective characteristic such as 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. 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 the interface characteristics between the inorganic first electrode 110 and the organic hole transport layer 150 . In one exemplary embodiment, the hole injection layer 140 may include 4,4',4"-tris(3-methylphenylamino)triphenylamine (4,4',4"-tris(3-methylphenylamino)triphenylamine; MTDATA), copper phthalocyanine (CuPc), 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-hexaazatriphenylenehexacapitrile (1,4,5,8,9,11- hexaazatriphenylenehexacarbonitrile; 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-ethylenedioxythiphene)polystyrene sulfonate; PEDOT/PSS) and/or 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 the like). The hole injection layer 140 may be omitted depending on the characteristics of the organic light emitting diode 100 .

The hole transport layer 150 is positioned between the first electrode 110 and the light emitting material layer 160 and adjacent to 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), NPD, 4,4'-bis(N-carbazolyl)- 1,1'-biphenyl (4,4'-bis(N-carbazolyl)-1,1'-biphenyl; CBP), 1,3-bis(N-carbazolyl)benzene (1,3-bis(N -carbazolyl)benzene;mCP), N-(biphenyl-4-yl)-9,9-dimethyl-N-(4-(9-phenyl-9H-carbazol-3-yl)phenyl)-9H-flu Oren-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-carbazol-3-yl)phenyl)biphenyl)-4-amine (N-(biphenyl-4) -yl)-N-(4-(9-phenyl-9H-carbazol-3-yl)phenyl)biphenyl-4-amine) or the like), 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, in the light emitting material layer 160 , about 1 to 30 wt% of a dopant may be added to the host, and blue light may be emitted.

The organic compound represented by Chemical Formulas 1 to 3 may be used as a host of the light emitting material layer 160 . Meanwhile, the dopant used in the light emitting material layer 160 may be a dopant having delayed fluorescence characteristics.

As described above, a compound having delayed fluorescence properties is activated by heat or an electric field to have an intermediate energy state such as an ICT complex form. Since both excitons having a singlet energy level and excitons having a triplet energy level are involved in light emission, the luminous efficiency of the organic light emitting diode 100 may be improved. In addition, when the difference (ΔE _ST ) between the excited state singlet energy level (S _1d ) and the triplet energy level (T _1d ) of the dopant is 0.3 eV or less, it transitions to the intermediate energy state at these energy levels, and finally the ground state , the quantum efficiency of the dopant may be improved. That is, the luminous efficiency may increase as ΔE _ST is smaller, and when the difference between the excited state singlet energy level (S ₁ ) and the excited state triplet energy level (T ₁ ) of the dopant is 0.3 eV or less, heat or electric field Singlet state excitons and triplet state excitons can be transitioned to the ICT complex state, which is an intermediate state.

In addition, in order to maximize luminous efficiency by delayed fluorescence, the excited state triplet energy level (T _1h , see FIG. 2) of the organic compound represented by Chemical Formulas 1 to 3 used as a host is a delayed fluorescent compound used as a dopant. should be higher than the triplet energy level of the excited state of T _1d (see Fig. 2). In particular, 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 energy level of the host When the difference between (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, energy is efficiently transferred from the host to the dopant, maximizing luminous efficiency can do.

According to one exemplary embodiment, when the organic compound represented by Chemical Formulas 1 to 3 is used as the host of the light emitting material layer 160 , it is better to use a dopant having an appropriate energy level with the host while exhibiting delayed fluorescence characteristics. may be desirable. For example, the delayed fluorescent dopant may be a delayed fluorescent dopant that emits blue light. In order to realize blue light emission at a level applicable to a display device, the excited state singlet energy level (S _1d ) of the delayed fluorescent dopant may be at a level of 2.7 to 2.8 eV, and the excited state triplet energy level (T _1d ) may be 2.4 to 2.5 eV or more, but the present invention is not limited thereto.

A blue light emission delaying fluorescent dopant that may be used as a dopant of the light emitting material layer 160 according to an exemplary embodiment of the present invention is 10-(4-(4,6-diphenyl-1,3,5-triazine-2). -yl)phenyl)-9,9-dimethyl-9,10-dihydroacridine (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) (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'-anthracen]-10'-one (10-phenyl-10H,10'H-spiro[acridine-9,9'-anthracen]- 10'-one, ACRSA), 3,6-dibenzoyl-4,5-di(1-methyl-9-phenyl-9H-carbazolyl)-2-ethynylbenzonitrile (3,6-dibenzoyl-4, 5-di(1-methyl-9-phenyl-9H-carbazoyl)-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 (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-triazine) -2-yl)-1,3-phenylene)bis(9H-carbazole)(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)(9,9',9",9"'-((6-phenyl-1,3,5-triazin-2, 4-diyl)bis(benzene-5,3,1-triyl))tetrakis(9H-carbazole, DDczTrz), bis(4-(9H-3,9'-bicarbazol-9-yl)phenyl)methanone (bis(4-(9H-3,9'-bicarbazol-9-yl)phenyl)methanone, CC2BP), 9'-[4-(4,6-diphenyl-1,3,5-triazine-2) -yl)phenyl]-3,3",6,6"-tetraphenyl-9,3',6',9"-tert-9H-carbazole (9'-[4-(4,6-diphenyl- 1,3,5-triazin-2-yl)phenyl]-3,3",6,6"-tetraphenyl-9,3':6',9"-ter-9H-carbazole, BDPCC-TPTA), 9 '-[4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl]-9,3':6',9"-tert-9H-carbazole (9'- [4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl]-9,3':,6',9"-ter-9H-carbazole, BCC-TPTA),

9,9'-(4,4'-sulfonylbis(4,1-phenylene))bis(3,6-dimethoxy-9H-carbazole)(9,9'-(4,4'-sulfonylbis) (4,1-phenylene))bis(3,6-dimethoxy-9H-carbazole), DMOC-DPS), 9-(4-(4,6-diphenyl-1,3,5-triazine-2- yl)phenyl)-3',6'-diphenyl-9H-3,9'-bicarbazole (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- Phenoxazine (10- (4,6-diphenyl-1,3,5-triazin-2-yl) -10H-phenoxazine, Phen-TRZ), 9- (4- (4,6-diphenyl-1,3) ,5-triazin-2-yl)phenyl)-9H-carbazole (9-(4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-9H-carbazole, Cab -Ph-TRZ), 2,3,4,6-tetra (9H-carbazol-9-yl) -5-fluorobenzonitrile (2,3,4,6-tetra (9H-carbazol-9-yl) )-5-fluorobenzonitrile, 4CZFCN), 10-(4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-10H-spiro[acridine-9,9 '-fluorene](10-(4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-10H-spiro[acridine-9,9'-fluorene], SpiroAC-TRZ ) or may be represented by the following Chemical Formula 4, but the present invention is not limited thereto.

Formula 4

For example, the dopant, which may be a delayed fluorescent dopant, may be added in an amount of 1 to 50 wt % in the light emitting material layer 160 , but the present invention is not limited thereto.

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 . The 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), 2-[4-(9,10-di-2-naphthalenyl-2-anthracenyl)phenyl]-1-phenyl-1H-benzimidazole ((2-[4-(9) ,10-di-2-naphthalenyl-2-anthracenyl)phenyl]-1-phenyl-1H-benzimidazole), 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), 3-(biphenyl-4-yl)-5-(4-tertbutylphenyl)-4-phenyl-4H-1,2,4-tria sol (3-(biphenyl-4-yl)-5-(4-terbutylphenyl)-4-phenyl-4H-1,2,4-triazole; TAZ); 4,7-diphenyl-1,10-phenanthroline (4,7-diphenyl-1,10-phenanthroline; Bphen), tris(phenylquinoxaline; TPQ), and/or 1,3 ,5-tris(N-phenylbenzimidazol-2-yl)benzene (1,3,5-tris(N-phenylbenzimiazole-2-yl)benzene; TPBi), etc., but the present invention is not limited thereto it is not

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

The organic light emitting diode 100 according to the exemplary embodiment of the present invention has a dopant having delayed fluorescence characteristics in the light emitting material layer 160 constituting the organic light emitting layer 130 . Since excitons in the singlet energy state and the triplet energy state are both involved in light emission, the luminous efficiency is improved. In addition, the light emitting material layer 160 includes a host made of an organic compound represented by Chemical Formulas 1 to 3.

The organic compounds represented by Chemical Formulas 1 to 3 have steric hindrance when combined with other moieties and have an indolocarbazole moiety that can function as an electron donor. The three-dimensional three-dimensional structure of the organic compound represented by Chemical Formulas 1 to 3 is limited and structurally robust. By using the organic compound represented by Chemical Formulas 1 to 3 as a host of the light emitting material layer, excellent color purity can be secured, low voltage driving is possible, and energy can be efficiently transferred to the dopant. The cyano group is connected to the indolocarbazole moiety to widen the energy bandgap, and the excited-state triplet energy level (T _1h ) is not lowered, so the luminous efficiency is improved, the blue transition is made, and the organic light-emitting diode (OLED) with excellent color purity ( 100) can be implemented.

Meanwhile, the organic light emitting diode according to the present invention may further include one or more exciton blocking layers. 4 is a cross-sectional view schematically showing 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 first and second electrodes 210 and 220 facing each other, and first and second electrodes 210 . , 220) and an organic light emitting layer 230 positioned between.

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

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 large work function value. The second electrode 220 may be a cathode, and may be formed of Al, Mg, Ca, Ag, which is a conductive material having a relatively low work function value, or an alloy or combination thereof.

The hole injection layer 240 is positioned between the first electrode 210 and the hole transport layer 22 . The hole injection layer 240 is MTDATA, 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 injection layer 240 may be omitted depending on the characteristics of the organic light emitting diode 200 .

The hole transport layer 250 is positioned between the first electrode 210 and the light emitting material layer 260 and adjacent to the light emitting material layer 260 . The hole transport layer 250 is TPD, NPD, CBP, mCP, 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-carbazol-3-yl)phenyl)biphenyl)- It may consist of an aromatic amine compound such as 4-amine.

The light emitting material layer 260 may be formed by doping a host with a dopant. For example, in the light emitting material layer 260 , about 1 to 50 wt% of a dopant may be added to the host, and blue light may be emitted. For example, an organic compound represented by Chemical Formulas 1 to 3 is used as a host of the light emitting material layer 260, and a compound exhibiting delayed fluorescence characteristics, for example, DMAC-TRZ, DMAC-DPS, ACRSA, Cz-VPN, TcZTrz, DczTrZ, DDczTrZ, CC2BP, BDPCC-TPTA, BCC-TPTA, DMOC-DPS, DPCC-TPTA, Phen-TRZ, Cab-Ph-TRZ, 4CZFCN, SpiroAC-TRZ and/or the compound represented by Formula 4 is It can be used as a dopant.

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, etc. It may be a derivative. For example, the electron transport layer 270 is Alq ₃ , PBD, spiro-PBD, Liq, 2-[4-(9,10-di-2-naphthalenyl-2-anthracenyl)phenyl]-1- Phenyl-1H-benzimidazole, BAlq, TAZ, It may be made of Bphen, TPQ, and/or TPBi, but the present invention is not limited thereto.

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

On the other hand, when holes move the light emitting material layer 260 to the second electrode 220 or electrons pass through the light emitting material layer 260 to the first electrode 210, the lifetime and efficiency of the device will 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, in the organic light emitting diode 200 according to the second embodiment of the present invention, an electron blocking layer capable of controlling and 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, tri-p-tolylamine, 1 ,1-bis(4-(N,N-di(p-tolyl)amino)phenyl)cyclohexane (1,1-bis(4-(N,N'-di(ptolyl)amino)phenyl)cyclohexane; TAPC ), MTDATA, 1,3-bis(N-carbazolyl)benzene (1,3-bis(N-carbazolyl)benzene; mCP), 3,3'-bis(N-carbazolyl)-1,1'- Biphenyl (3,3'-bis(N-carbazolyl)-1,1'-biphenyl; mCBP), TPD, 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, the hole blocking layer 265 as a second exciton blocking layer is positioned between the light emitting material layer 260 and the electron transport layer 270 to prevent the movement of holes between the light emitting material layer 260 and the electron transport layer 270 . do. In one exemplary embodiment, oxadiazole, triazole, phenanthroline, benzoxazole, benzo which may be used in the electron transport layer 270 as a material of the hole blocking layer Derivatives such as thiazole, benzimidazole, and triazine may be used.

For example, the hole blocking layer 265 has a lower HOMO (highest occupied molecular orbital; 2,9-dimethyl-4,7-di) energy level than the material used for the light emitting material layer 260 . phenyl-1,10-phenanthroline (2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline; BCP), BAlq, Alq3, PBD, spiro-PBD and/or Liq, etc. .

Since the organic light emitting diode 200 according to the second embodiment of the present invention has a dopant having a delayed fluorescence characteristic in the light emitting material layer 260 , luminous efficiency is improved. In addition, the light emitting material layer 260 includes a host made of an organic compound represented by Chemical Formulas 1 to 3.

The organic compounds represented by Chemical Formulas 1 to 3 can function as an electron donor and have an indolocarbazole moiety that binds in a twisted form when combined with other moieties, so the three-dimensional three-dimensional structure is limited and structural sturdy with The organic compounds represented by Chemical Formulas 1 to 3 have excellent color purity, can be driven at a low voltage, and can efficiently transfer energy to a dopant.

In addition, since the cyano group is connected to the indolocarbazole moiety, the energy bandgap is wide, the excited state triplet energy level (T _1h ) is not lowered, so the luminous efficiency is improved, the blue transition is made, and the organic having excellent color purity The light emitting diode 200 may be implemented.

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 and 265 , the light emitting material layer 260 and adjacent charge transport layers 250 and 270 . By preventing light emission at the interface with the organic light emitting diode 200, the light emitting efficiency and stable low voltage driving characteristics 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-described organic light emitting diode is applied. As an example of the organic light emitting device according to the present invention, a display device to which the above-described organic light emitting diode 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 the 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 , and in FIG. 3 , a driving thin film having a coplanar structure A transistor Td is shown.

The substrate 302 may be a glass substrate, a thin flexible substrate, or a polymer plastic substrate. For example, the flexible substrate includes polyimide (PI), polyethersulfone (PES), polyethylenenaphthalate (PEN), polyethylene terephthalate (PET), and polycarbonate (PC). It may 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 is positioned form an array substrate.

A semiconductor layer 310 is formed on the substrate 302 . For example, the semiconductor layer 310 may be formed of an oxide semiconductor material. In this case, a light blocking pattern (not shown) and a buffer layer (not shown) may be formed under the semiconductor layer 310 , and the light blocking pattern prevents light from being incident on the semiconductor layer 310 so that the semiconductor layer 310 prevents the light from entering the semiconductor layer 310 . to prevent deterioration 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 layer 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 made of an inorganic insulating material such as silicon oxide (SiO ₂ ) or silicon nitride (SiNx).

The gate electrode 330 made of a conductive material such as metal is formed on the gate insulating layer 320 to correspond to the center of the semiconductor layer 310 . Also, a gate line (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 layer 320 is formed on the entire surface of the substrate 302 , the gate insulating layer 320 may be patterned in the same shape as the gate electrode 330 .

An interlayer insulating layer 340 made of an insulating material is formed on the entire surface of the substrate 302 on the gate electrode 330 . The interlayer insulating layer 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. have.

The interlayer insulating layer 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 positioned at both sides of the gate electrode 330 to be spaced apart from 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 layer 320 is patterned to have 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 layer 340 .

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

The source electrode 352 and the drain electrode 354 are spaced apart from the center of the gate electrode 330 , respectively, on both sides of the semiconductor layer 310 through the first and second semiconductor layer contact holes 342 and 344 , respectively. 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 for 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 to form a storage capacitor using the interlayer insulating film 340 between the first and second capacitor electrodes as a dielectric layer.

Meanwhile, the semiconductor layer 310 , the gate electrode 330 , the source electrode 352 , and the drain electrode 354 form the 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 the semiconductor layer 310 . Alternatively, the driving thin film transistor Td may have an inverted staggered structure in which a gate electrode is positioned under a semiconductor layer and a source electrode and a drain electrode are positioned over 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 a structure substantially the same as that of 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 a 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, a gate electrode (not shown) and a source electrode (not shown) of the switching thin film transistor (not shown) are respectively connected to a gate line and a data line.

Meanwhile, the organic light emitting diode display 300 may include a color filter (not shown) that absorbs 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 for absorbing light may be formed separately for each pixel area, and each of these color filter patterns is an organic light emitting diode (OLED) emitting light of a wavelength band to be absorbed. The organic light emitting layer 430 in 400 may be overlapped with each other. By adopting a color filter (not shown), the organic light emitting diode display 300 may realize full-color.

For example, when the organic light emitting diode display 300 is a bottom light emitting type, a color filter (not shown) that absorbs light may be positioned on the interlayer insulating film 340 corresponding to the organic light emitting diode 400 . . In an alternative embodiment, when the organic light emitting diode display 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 over the entire surface of the substrate 302 on the source electrode 352 and the drain electrode 354 . The planarization layer 360 has a flat top 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 directly above the second semiconductor layer contact hole 344 , but may be formed to be spaced apart from the second semiconductor layer contact hole 344 .

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

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 large 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 under the first electrode 310 . For example, the reflective electrode or the reflective layer may be formed of an aluminum-palladium-copper (APC) alloy.

Also, 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 light emitting 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 a light emitting material layer. On the other hand, as shown in FIGS. 3 to 4 , the organic light emitting layer 430 includes a plurality of holes such as 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 consist of an organic material layer of

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 small work function value and may be used as a cathode. For example, the second electrode 420 may be formed of any one of an alloy or combination thereof such as aluminum (Al), magnesium (Mg), calcium (ca), silver (Ag), or an aluminum-magnesium alloy (AlMg). can

On the second electrode 420 , an encapsulation film 380 is formed to prevent external moisture from penetrating 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, since the organic light emitting diode 400 has a dopant having a delayed fluorescence characteristic in the organic light emitting layer 430 , luminous efficiency is improved. In addition, the organic light emitting layer 430 includes an organic compound represented by Chemical Formulas 1 to 3 as a host.

The organic compounds represented by Chemical Formulas 1 to 3 have a rigid structure due to a limited three-dimensional three-dimensional structure. In addition, in the organic compounds represented by Chemical Formulas 1 to 3, a cyano group is connected to the indolocarbazole moiety, so that the energy band gap and the excited state triplet energy level (T _1h ) do not decrease, and a blue transition can be implemented. . Therefore, by applying the organic compound represented by Chemical Formulas 1 to 3 to the organic light emitting layer 430 , the color purity and luminous efficiency of the organic light emitting diode 400 and the organic light emitting diode display 300 can be improved, and the organic light emitting diode display can be improved at low voltage. The light emitting diode 400 may be driven.

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

Synthesis example 1: Synthesis of compound 1

1) Synthesis of compound 1B

In a nitrogen environment (N ₂ purging), 1A and 0.9 equivalents of CuCN were put in DMF (dimethyl formamdie) and stirred at 150°C. After 24 hours, the reactant was slowly poured into ice water at 0° C., stirred for 30 minutes, and then an aqueous ammonia solution was added to extract. After removing the solvent from the solvent layer and adsorbing it to silica, an ivory solid 1B was obtained after column using MC: Hexane (1:3) developing solvent.

2) Synthesis of compound 1

In a nitrogen environment (N ₂ purging), 1B, 1.2 equivalents of 1C, 0.1 equivalents of Tris(dibenzylideneacetone)dipalladium(0)(Pd ₂ (dba) ₃ ), 0.1 equivalents of triphenylphosphine, and 3.0 equivalents of sodium tert-butoxide were added to Toluene and stirred in an oil bath at 100°C. After 14 hours, water was added to the reaction mixture, and after extraction, a white solid compound 1 was obtained after column using Hexane: MC (2:1) as a developing solvent. The excited state triplet energy level of Compound 1 is approximately 3.2 eV, and the results of NMR analysis of the synthesized Compound 1 are shown in FIG. 6 .

Synthesis example 2: Synthesis of compound 2

In a nitrogen environment (N ₂ purging), 1B, 1.4 equivalents of 2A, 0.05 equivalents of Pd ₂ (dba) ₃ , 0.1 equivalents of triphenyphosphine, and 3.0 equivalents of sodium tert-butoxide were added to toluene and stirred in an oil bath at 100°C. After 24 hours, water was added to the reaction mixture, and after extraction, a white solid compound 2 was obtained after column using Hexane: MC (2:1) as a developing solvent. The excited state triplet energy level of Compound 2 is approximately 3.1 eV, and the results of NMR analysis of the synthesized Compound 2 are shown in FIG. 7 .

Synthesis example 3: Synthesis of compound 3

1) 3B compound synthesis

In a nitrogen environment (N ₂ purging), 3A and 1.5 equivalents of CuCN were added to DMF and stirred at 150°C. After 48 hours, the reaction product is slowly poured into ice water at 0° C., stirred for 30 minutes, and then an aqueous ammonia solution is added for extraction. After removing the solvent from the solvent layer and adsorbing it to silica, an ivory solid 3B was obtained after column using MC: Hexane (1:1) developing solvent.

2) Synthesis of compound 3

In a nitrogen environment (N ₂ purging), 1B, 1.3 equivalents of 3B, 0.05 equivalents of Pd ₂ (dba) ₃ , 0.1 equivalents of triphenylphosphine, and 3.0 equivalents of sodium tert-butoxide were added to toluene and stirred in an oil bath at 100°C. After 14 hours, water was added to the reaction mixture, and after extraction, a white solid compound 3 was obtained after column using Hexane:MC (1:1) developing solvent.

Synthesis example 4: Synthesis of compound 4

1) Synthesis of compound 4B

In a nitrogen environment (N ₂ purging), 4A and 2.5 equivalents of CuCN were added to DMF and stirred at 150°C. After 72 hours, the reactant is slowly poured into ice water at 0° C., stirred for 30 minutes, and then an aqueous ammonia solution is added to extract. After removing the solvent from the solvent layer and adsorbing it to silica, an ivory solid 4B was obtained after column using MC developing solvent.

2) Synthesis of compound 4

In a nitrogen environment (N ₂ purging), 1B, 1.4 equivalents of 4B, 0.05 equivalents of Pd ₂ (dba) ₃ , 0.1 equivalents of triphenylphosphine, and 3.0 equivalents of sodium tert-butoxide were added to toluene and stirred in an oil bath at 100°C. After 24 hours, water was added to the reaction mixture, and after extraction, a white solid compound 4 was obtained after column using Hexane:MC (2:3) developing solvent.

Synthesis example 5: Synthesis of compound 5

1) Synthesis of compound 5C

In a nitrogen environment (N ₂ purging), 5A, 0.6 equivalents of 5B, 0.1 equivalents of CuI, 3.5 equivalents of diaminocyclohexane, and 4.0 equivalents of potassium phosphate were added to 1,4-dioxane and stirred in an oil bath at 90°C. After 12 hours, water was added to the reaction mixture, and after extraction, a white solid 5C was obtained after column using Hexane: MC (5:1) as a developing solvent.

2) compound 5D synthesis

In a nitrogen environment (N ₂ purging), 5C, 1.5 equivalents of Bu-Li was added to Ether and stirred at -78°C. After 2 hours of reaction, 1.2 equivalents of trimethyl borate was added, stirred at -78°C for 30 minutes, and then the dry ice bath was removed to raise the reaction temperature to room temperature. After 8 hours of reaction, 30 ml of HCl in DI water is added and the organic solvent is removed. All organic solvents are removed and a white solid 5D precipitated in water is obtained by filtering.

2) Synthesis of compound 5

In a nitrogen environment (N ₂ purging), 1B, 1.3 equivalents of 5D, 0.05 equivalents of Pd ₂ (dba) ₃ , and 4.0 equivalents of potassium carbonate were added to toluene and stirred in an oil bath at 80°C. After 15 hours, water was added to the reaction mixture, and after extraction, a white solid compound 5 was obtained after column using Hexane:EA (1:1) developing solvent.

Synthesis example 6: Synthesis of compound 6

1) Synthesis of compound 6A

In a nitrogen environment (N ₂ purging), 5A, 0.6 equivalents of 2A, 0.1 equivalents of CuI, 3.5 equivalents of diaminocyclohexane, and 4.0 equivalents of potassium phosphate were added to 1,4-dioxane and stirred in an oil bath at 90°C. After 12 hours, water was added to the reaction mixture, and after extraction, a white solid 6A was obtained after column using Hexane: MC (4:1) developing solvent.

2) Synthesis of compound 6B

In a nitrogen environment (N ₂ purging), 6A and 1.5 equivalents of Bu-Li were added to Ether and stirred at -78°C. After 2 hours of reaction, 1.2 equivalents of trimethyl borate was added, stirred at -78°C for 30 minutes, and then the dry ice bath was removed to raise the reaction temperature to room temperature. After 8 hours of reaction, 30 ml of HCl in DI water is added and the organic solvent is removed. All organic solvents are removed and a white solid D precipitated in water is obtained by filtration.

3) Synthesis of compound 6

In a nitrogen environment (N ₂ purging), 1B, 1.3 equivalents of 6B, 0.05 equivalents of Pd ₂ (dba) ₃ , and 4.0 equivalents of potassium carbonate were added to toluene and stirred in an oil bath at 80°C. After 15 hours, water was added to the reaction mixture, and after extraction, a white solid compound 6 was obtained after column using Hexane:EA (4:1) as a developing solvent.

Synthesis example 7: Synthesis of compound 7

1) Synthesis of compound 7B

In a nitrogen environment (N ₂ purging), 7A, 0.6 equivalents of 2A, 0.1 equivalents of CuI, 3.5 equivalents of diaminocyclohexane, and 4.0 equivalents of potassium phosphate were placed in 1,4-dioxane and stirred in an oil bath at 90°C. After 12 hours, water was added to the reaction mixture, and after extraction, a white solid 7B was obtained after column using Hexane: MC (4:1) as a developing solvent.

2) Synthesis of compound 7C

In a nitrogen environment (N ₂ purging), 7B and 1.5 equivalents of Bu-Li were added to Ether and stirred at -78°C. After 2 hours of reaction, 1.2 equivalents of trimethyl borate was added, stirred at -78°C for 30 minutes, and then the dry ice bath was removed to raise the reaction temperature to room temperature. After 8 hours of reaction, 30 ml of HCl in DI water is added and the organic solvent is removed. All organic solvents are removed and the white solid 7C precipitated in water is obtained by filtering.

2) Synthesis of compound 7

In a nitrogen environment (N ₂ purging), 1B, 2.2 equivalents of 7C, 0.05 equivalents of Pd ₂ (dba) ₃ , and 4.0 equivalents of potassium carbonate were added to toluene and stirred in an oil bath at 80°C. After 15 hours, water was added to the reaction mixture, and after extraction, a white solid compound 7 was obtained after column using Hexane:EA (4:1) as a developing solvent.

Synthesis example 8: Synthesis of compound 8

1) Synthesis of compound 8A

In a nitrogen environment (N ₂ purging), 5A, 0.6 equivalents of 3B, 0.1 equivalents of CuI, 3.5 equivalents of diaminocyclohexane, and 4.0 equivalents of potassium phosphate were added to 1,4-dioxane and stirred in an oil bath at 90°C. After 12 hours, water was added to the reaction mixture, and after extraction, a white solid 8A was obtained after column using Hexane: MC (2:1) developing solvent.

2) Synthesis of compound 8B

In a nitrogen environment (N ₂ purging), 8A, 1.5 equivalents of Bu-Li was added to Ether and stirred at -78°C. After 2 hours of reaction, 1.2 equivalents of trimethyl borate was added, stirred at -78°C for 30 minutes, and then the dry ice bath was removed to raise the reaction temperature to room temperature. After 8 hours of reaction, 30 ml of HCl in DI water is added and the organic solvent is removed. All organic solvents are removed and the white solid 8B precipitated in water is obtained by filtration.

3) Synthesis of compound 8

In a nitrogen environment (N ₂ purging), 1B, 1.3 equivalents of 8B, 0.05 equivalents of Pd ₂ (dba) ₃ , and 4.0 equivalents of potassium carbonate were added to toluene and stirred in an oil bath at 80°C. After 15 hours, water was added to the reaction mixture, and after extraction, a white solid compound 8 was obtained after column using Hexane:EA (1:1) developing solvent.

Synthesis example 9: Synthesis of compound 9

1) Synthesis of compound 9A

In a nitrogen environment (N ₂ purging), 7A, 0.6 equivalents of 3B, 0.1 equivalents of CuI, 3.5 equivalents of diaminocyclohexane, and 4.0 equivalents of potassium phosphate were placed in 1,4-dioxane and stirred in an oil bath at 90°C. After 12 hours, water was added to the reaction mixture, and after extraction, a white solid 9A was obtained after column using Hexane: MC (2:1) as a developing solvent.

2) Synthesis of compound 9B

In a nitrogen environment (N ₂ purging), 9A and 1.5 equivalents of Bu-Li were added to Ether and stirred at -78°C. After 2 hours of reaction, 1.2 equivalents of trimethyl borate was added, stirred at -78°C for 30 minutes, and then the dry ice bath was removed to raise the reaction temperature to room temperature. After 8 hours of reaction, 30 ml of HCl in DI water is added and the organic solvent is removed. All organic solvents are removed and 9B, a white solid precipitated in water, is obtained by filtration.

3) Synthesis of compound 9

In a nitrogen environment (N ₂ purging), 1B, 1.3 equivalents of 9B, 0.05 equivalents of Pd ₂ (dba) ₃ , and 4.0 equivalents of potassium carbonate were added to toluene and stirred in an oil bath at 80°C. After 15 hours, water was added to the reaction mixture, and after extraction, a white solid compound 9 was obtained after column using Hexane:EA (1:1) developing solvent.

Synthesis example 10: Synthesis of compound 10

1) Synthesis of compound 10A

In a nitrogen environment (N ₂ purging), 5A, 0.6 equivalents of 4B, 0.1 equivalents of CuI, 3.5 equivalents of diaminocyclohexane, and 4.0 equivalents of potassium phosphate were added to 1,4-dioxane and stirred in an oil bath at 90°C. After 12 hours, water was added to the reaction mixture, and after extraction, a white solid 10A was obtained after column using Hexane: MC (1:1) developing solvent.

2) Synthesis of compound 10B

In a nitrogen environment (N ₂ purging), 10A, 1.5 equivalents of Bu-Li was added to Ether and stirred at -78°C. After 2 hours of reaction, 1.2 equivalents of trimethyl borate was added, stirred at -78°C for 30 minutes, and then the dry ice bath was removed to raise the reaction temperature to room temperature. After 8 hours of reaction, 30 ml of HCl in DI water is added and the organic solvent is removed. All organic solvents are removed and 10B, a white solid precipitated in water, is obtained by filtration.

3) Synthesis of compound 10

In a nitrogen environment (N ₂ purging), 1B, 1.3 equivalents of 10B, 0.05 equivalents of Pd ₂ (dba) ₃ , and 4.0 equivalents of potassium carbonate were added to toluene and stirred in an oil bath at 80°C. After 15 hours, water was added to the reaction mixture, and after extraction, a white solid compound 10 was obtained after column using Hexane:EA (1:2) developing solvent.

Synthesis example 11: Synthesis of compound 11

1) Synthesis of compound 11A

In a nitrogen environment (N ₂ purging), 7A, 0.6 equivalents of 4B, 0.1 equivalents of CuI, 3.5 equivalents of diaminocyclohexane, and 4.0 equivalents of potassium phosphate were placed in 1,4-dioxane and stirred in an oil bath at 90°C. After 12 hours, water was added to the reaction mixture, and after extraction, a white solid 11A was obtained after column using Hexane: MC (1:1) developing solvent.

2) Synthesis of compound 11B

In a nitrogen environment (N ₂ purging) 11A, 1.5 equivalents of Bu-Li was put into Ether and stirred at -78°C. After 2 hours of reaction, 1.2 equivalents of trimethyl borate was added, stirred at -78°C for 30 minutes, and then the dry ice bath was removed to raise the reaction temperature to room temperature. After 8 hours of reaction, 30 ml of HCl in DI water is added and the organic solvent is removed. All organic solvents are removed and 11B, a white solid precipitated in water, is obtained by filtration.

2) Synthesis of compound 11

In a nitrogen environment (N ₂ purging), 1B, 1.3 equivalents of 11B, 0.05 equivalents of Pd ₂ (dba) ₃ , and 4.0 equivalents of potassium carbonate were added to toluene and stirred in an oil bath at 80°C. After 15 hours, water was added to the reaction mixture, and after extraction, a white solid compound 11 was obtained after column using Hexane:EA (1:2) developing solvent.

Synthesis example 12: Synthesis of compound 12

1) Synthesis of compound 12B

In a nitrogen environment (N ₂ purging), 12A and 0.8 equivalents of CuCN were added to DMF and stirred at 150°C. After 24 hours, the reaction product was slowly poured into ice water at 0° C., stirred for 30 minutes, and then an aqueous ammonia solution was added for extraction. After removing the solvent from the solvent layer and adsorbing it to silica, an ivory solid 12B was obtained after column using MC: Hexane (1:3) developing solvent. .

2) Synthesis of compound 12

In a nitrogen environment (N ₂ purging), 12B, 1.2 equivalents of 1C, 0.05 equivalents of Pd ₂ (dba) ₃ , 0.1 equivalents of triphenylphosphine, and 3.0 equivalents of sodium tert-butoxide were added to Toluene and stirred in an oil bath at 100°C. After 24 hours, water was added to the reaction water, and after extraction, a white solid compound 12 was obtained after a column using a developing solvent of Hexane: MC (2:1). The excited state triplet energy level of compound 13 is approximately 3.2 eV, and the results of NMR analysis of the synthesized compound 12 are shown in FIG. 8 .

Synthesis example 13: Synthesis of compound 13

In a nitrogen environment (N ₂ purging), 12B, 1.4 equivalents of 2A, 0.05 equivalents of Pd ₂ (dba) ₃ , 0.1 equivalents of triphenylphosphine, and 3.0 equivalents of sodium tert-butoxide were added to Toluene and stirred in an oil bath at 100°C. After 26 hours, water was added to the reaction mixture, and after extraction, a white solid compound 13 was obtained after column using Hexane: MC (2:1) as a developing solvent.

Synthesis example 14: Synthesis of compound 14

In a nitrogen environment (N ₂ purging), 12B, 1.3 equivalents of 3B, 0.05 equivalents of Pd ₂ (dba) ₃ , 0.1 equivalents of triphenylphosphine, and 3.0 equivalents of sodium tert-butoxide were added to toluene and stirred in an oil bath at 100°C. After 36 hours, water was added to the reaction mixture, and after extraction, a white solid compound 14 was obtained after column using Hexane:MC (1:2) developing solvent.

Synthesis example 15: Synthesis of compound 15

In a nitrogen environment (N ₂ purging), 12B, 1.4 equivalents of 4B, 0.05 equivalents of Pd ₂ (dba) ₃ , 0.1 equivalents of triphenylphosphine, and 3.0 equivalents of sodium tert-butoxide were added to toluene and stirred in an oil bath at 100°C. After 24 hours, water was added to the reaction mixture, and after extraction, a white solid compound 15 was obtained after column using Hexane: MC (2:3) as a developing solvent.

Example 1: Applying compound 1 organic light emitting diode produce

An organic light emitting diode was manufactured in which Compound 1 was applied as a host of the light emitting material layer. First, a glass substrate with an ITO (including a reflector) electrode having a thickness of 40 mm x 40 mm x 0.5 mm 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, O ₂ plasma treatment was performed for 2 minutes in a vacuum state and transferred to a deposition chamber to deposit other layers thereon. An organic layer was deposited in the following order by evaporation from a heating boat under a vacuum of about 10 ^-7 Torr.

A hole injection layer (NPB, 50 Å), a hole transport layer (mCP, 500 Å), an electron blocking layer (mCBP, 100 Å), a light emitting material layer (Compound 1 is used as a host and the material of Formula 4 is 30 wt% doped, 250 Å), electron transport layer (TPBI, 300 Å), electron injection layer (LiF), cathode (Al).

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

Example 2: Applying compound 2 organic light emitting diode produce

An organic light emitting diode was manufactured by repeating the procedure of Example 1 except that Compound 2 was used instead of Compound 1 as a host of the light emitting material layer.

Example 3: Applying compound 12 organic light emitting diode produce

An organic light emitting diode was manufactured by repeating the procedure of Example 1 except that Compound 12 was used instead of Compound 1 as a host of the light emitting material layer.

comparative example : organic light emitting diode produce

An organic light emitting diode was manufactured by repeating the procedure of Example 1 except that a material represented by the following formula 5 (excitation state triplet energy level is about 2.9 eV) was used instead of Compound 1 as a host of the light emitting material layer.

Formula 5

Experimental example : organic light emitting diode Measurement of luminescence properties

Physical properties were measured for each of the organic light emitting diodes manufactured in Examples 1 to 4 and Comparative Examples. 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 measurement results of current efficiency, power efficiency, external quantum efficiency (EQE), and CIE color coordinates of the produced organic light emitting diode are shown in Table 1 below.

Physical properties of organic light emitting diodes device Voltage
(V) current efficiency
(Cd/A) power efficiency
(lm/W) EQE
(%) CIE
(X) CIE
(Y) Example 1 3.63 24.12 20.86 14.12 0.146 0.186 Example 2 3.75 26.30 21.18 15.23 0.151 0.201 Example 3 3.59 25.31 23.47 16.03 0.149 0.195 comparative example 3.67 23.03 19.69 12.88 0.161 0.297

As shown in Table 1, compared with the case of using the organic compound of Comparative Example as the host of the light emitting material layer, when the organic compound synthesized according to the present invention was used as the host of the light emitting material layer, the driving voltage was reduced by up to 2.2%. , the current efficiency was improved up to 16.5%, the power efficiency up to 19.2%, and the external quantum efficiency up to 24.5%. In addition, it was confirmed that blue of high color purity can be obtained even in color coordinates when the organic compound of the present invention is used as a host. As a result, by applying the organic compound of the present invention to the organic light emitting layer, it is possible to manufacture an organic light emitting diode with greatly improved luminous efficiency and improved color purity. Therefore, by using the organic light emitting diode to which the organic compound of the present invention is applied, it can be utilized in an organic light emitting device.

In the above, the present invention has been described based on exemplary embodiments and examples of the present invention, but the scope of the present invention is not limited to the technical ideas described in the embodiments and examples. Those of ordinary skill in the art to which the present invention pertains can easily propose various modifications and changes based on the above-described embodiments and examples. However, it is clear from the appended claims that all such 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: electron blocking layer
265: hole blocking layer 300: organic light emitting diode display device

Claims (16)

delete delete delete a first electrode and a second electrode facing each other; and
An organic light emitting layer positioned between the first electrode and the second electrode and including a light emitting material layer,
The light emitting material layer includes an organic compound represented by the following Chemical Formula 1 and a delayed fluorescent dopant, wherein the organic compound is a host of the light emitting material layer.
Formula 1

(In Formula 1, R ₁ and R ₂ are each independently a hydrogen atom, a deuterium atom, a tritium atom, an unsubstituted or substituted C ₅ ~ C ₃₀ aryl group, or an unsubstituted or substituted C ₄ ~ C ₃₀ heteroaryl group, and , at least one of R ₁ and R ² is an unsubstituted or substituted C ₅ -C ₃₀ aryl group or an unsubstituted or substituted C ₄ -C ₃₀ heteroaryl group; L ₁ and L ₂ are each independently unsubstituted or substituted a C5~ C30 arylene group or an unsubstituted or substituted C4~ C30 hetero arylene group; a and b are each 0 or 1)
5. The method of claim 4,
The organic compound is an organic light emitting diode represented by the following formula (2).
Formula 2

(In Formula 2, a and b are each the same as defined in Formula 1; R ₃ and R ₄ are each independently an unsubstituted or substituted C4~ C30 heteroaryl group; L ₃ and L ₄ are each independently unsubstituted or a substituted C4~ C30 hetero arylene group)
delete delete 5. The method of claim 4,
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 delayed fluorescent dopant (|HOMO ^H -HOMO ^D |) or the lowest unoccupied molecule of the host The difference between the orbital energy level (LUMO ^H ) and the lowest unoccupied molecular orbital energy level (LUMO ^D ) of the delayed fluorescent dopant (|LUMO ^H -LUMO ^D |) is 0.5 eV or less.
5. The method of claim 4,
The difference (ΔE _ST ) between the excited state singlet energy level (S ₁ ) and the excited state triplet energy level (T ₁ ) of the delayed fluorescent dopant is 0.3 eV or less.
Board;
an organic light emitting diode positioned on the substrate and according to any one of claims 4, 5, 8 and 9; and
A driving element positioned on the substrate and connected to the first electrode of the organic light emitting diode
An organic light emitting device comprising a.
11. The method of claim 10,
The organic light emitting device includes an organic light emitting diode display. 5. The method of claim 4,
The organic compound represented by the formula (1) is an organic light emitting diode of any one of the organic compounds represented by the following formula (3).
Formula 3

6. The method of claim 5,
R ₃ and R ₄ of Formula 2 are each independently unsubstituted or substituted with any one of a cyano group, a C ₁ to C ₂₀ alkyl group, a C ₅ to C ₃₀ aryl group, and a C ₄ to C ₃₀ heteroaryl group. Diyl, acridinyl group, dihydroacridinyl group, furobypyridyl group, fluorenyl group or xanthenyl group of the organic light emitting diode.
6. The method of claim 5,
R ₃ and R ₄ of Formula 2 are each independently

,

,

,

or

phosphorous organic light emitting diode.
5. The method of claim 4,
The delayed fluorescence dopant is an organic light emitting diode including a blue emission delayed fluorescence dopant.
16. The method of claim 15,
The blue light emission delaying fluorescent dopant is 10-(4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-9,9-dimethyl-9,10-dihydroa Creidine (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)(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(10-phenyl-10H,10'H-spiro[acridine-9,9'-anthracen]-10'-one, ACRSA), 3,6-dibenzoyl-4,5- Di(1-methyl-9-phenyl-9H-carbazoyl)-2-ethynylbenzonitrile (3,6-dibenzoyl-4,5-di(1-methyl-9-phenyl-9H-carbazoyl)-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 (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 ) (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)(9,9',9",9"'-((6-phenyl-1,3,5-triazin-2,4-diyl)bis(benzene-5,3,1-triyl))tetrakis(9 H-carbazole, DDczTrz), bis(4-(9H-3,9'-bicarbazol-9-yl)phenyl)methanone (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"-tert-9H-carbazole(9'-[4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl]-3,3",6,6"-tetraphenyl-9,3':6',9"-ter-9H-carbazole, BDPCC-TPTA), 9'-[4-(4,6-diphenyl-1,3,5- Triazin-2-yl)phenyl]-9,3':6',9"-tert-9H-carbazole (9'-[4-(4,6-diphenyl-1,3,5-triazin-2) -yl)phenyl]-9,3':,6',9"-ter-9H-carbazole, BCC-TPTA), 9,9'-(4,4'-sulfonylbis(4,1-phenylene) ))bis(3,6-dimethoxy-9H-carbazole)(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 (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-phenoxazine (10- (4,6-diphenyl-1,3,5-triazin-2) -yl)-10H-phenoxazine, Phen-TRZ), 9-(4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-9H-carbazole (9-( 4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-9H-carbazole, Cab-Ph-TRZ), 2,3,4,6-tetra(9H-carbazole- 9-yl)-5-fluorobenzonitrile (2,3,4,6-tetra(9H-carbazol-9-yl)-5- fluorobenzonitrile, 4CZFCN), 10-(4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-10H-spiro[acridine-9,9'-fluorene ](10-(4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-10H-spiro[acridine-9,9'-fluorene], SpiroAC-TRZ) or the formula An organic light emitting diode comprising a compound represented by 4.
Formula 4

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