KR20190068103A - Organic compounds having enhanced thermal resistance, organic light emitting diode and orgnic light emitting device having the compounds - Google Patents

Abstract

The present invention relates to an organic compound comprising carbazole moieties having p-type properties and dibenzofurane or dibenzothiophene derivatives having n-type properties which are connected to carbazole moieties and are substituted by other dibenzofuran or dibenzothiophene moieties. Since the organic compound of the present invention comprises a plurality of condensed heteroaromatic rings, it not only has excellent heat resistance, but also has a relatively high energy level. An organic light emitting diode and an organic light emitting device having improved luminous efficiency and a device lifespan can be manufactured by applying the organic compound of the present invention.

Description

TECHNICAL FIELD [0001] The present invention relates to an organic compound having excellent heat resistance, an organic light emitting diode including the organic compound, and an organic light emitting device using the organic compound. [0002]

The present invention relates to an organic compound, and more particularly, to an organic compound having excellent heat resistance and luminescence properties, an organic light emitting diode including the same, and an organic light emitting device.

BACKGROUND ART [0002] Organic light emitting diodes (OLEDs) as one of widely used flat display devices are now attracting attention as display devices that quickly replace liquid crystal display devices. Organic light emitting diodes (OLEDs) are formed of thin organic thin films within 2000 Å, and it is possible to realize images in a single direction or in both directions depending on the configuration of the electrodes used. In addition, the organic light emitting diode display device can form a device on a flexible transparent substrate such as a plastic, so that it is easy to realize a flexible or foldable display device. In addition, the organic light emitting diode display device can be driven at a low voltage, has excellent color purity, and has a great advantage over a liquid crystal display device.

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. (EIL), an electron transport layer (ETL), an electron transport layer (ETL), and an electron injection layer (EIL) are sequentially stacked on the hole injection electrode. ). At this time, holes injected from the anode and electrons injected from the cathode are combined in the light emitting material layer to form an exciton (exciton) to become an unstable excited state, and a stable ground state ground state and emits light.

The practical efficiency characteristic of the organic light emitting diode is determined by the external quantum efficiency which finally measures the amount of light emitted to the outside. External quantum efficiency can be measured by factors such as internal quantum efficiency (IQE), charge balancing factor, emission quantum efficiency, and out-coupling efficiency.

When a hole and an electron meet to form an exciton, a singlet exciton in a paired spin form and a triplet exciton in an unpaired spin form are formed at a ratio of 1: 3 < / RTI > Since a general fluorescent material can not emit a triplet exciton because only a single exciton participates in light emission and the remaining 75% of triplet excitons can not participate in light emission, the internal quantum efficiency is only 0.25 . Therefore, when the factors such as the charge balance factor, the spin quantum efficiency, and the light extraction efficiency are all combined, the maximum luminous efficiency of the organic light emitting diode using the fluorescent material is only 5 to 7.5%.

A phosphorescent material has been developed to overcome the limitations of fluorescent materials, and heavy metal complexes are generally used as phosphorescent materials. In the case of the phosphorescent material, the singlet-state exciton transitions to the triplet state mostly through intersystem crossing (ISC), and the energy of the triplet state is transferred to the bottom by the strong spin- orbit coupling by heavy metal Lt; / RTI > As such, the phosphorescent material has a luminescent mechanism that converts both singlet energy and triplet energy into light. Therefore, the phosphorescent material can realize an external quantum efficiency of up to 20 to 30%.

However, the metal complex used as a conventional phosphorescent material has a very short life span and thus has limitations in commercialization. Particularly, since the blue phosphorescent material has a low color purity, it has a limitation in applying the blue phosphorescent material to a high-quality display. Furthermore, in order to prevent the triplet energy of the phosphorescent dopant from transferring back energy to the host, the triplet energy of the phosphorescent host must be higher than the triplet energy of the phosphorescent dopant. However, the organic materials that can be used as a phosphorescent host are extremely limited, because the organic aromatics are greatly reduced in triplet energy as conjugation is increased or the rings are fused rings.

In addition, conventional phosphorescent hosts are designed to have an excessively high bandgap of 3.5 to 4.5 eV or higher in order to have high triplet energy. When a host having an excessively wide band gap is used, charge injection and transportation are not smooth, and therefore a high driving voltage is required, which may adversely affect lifetime characteristics of the device. Therefore, there is a need to develop a light emitting diode and a light emitting device using a light emitting material having excellent luminescence efficiency and improved lifetime characteristics.

It is an object of the present invention to provide an organic compound capable of preventing non-luminescence disappearance in a luminescent mechanism.

It is another object of the present invention to provide an organic light emitting diode and an organic light emitting device having good light emitting efficiency and improved lifetime characteristics.

According to one aspect of the present invention, the present invention provides carbazole moiety having a p-type characteristic, carbazole moiety having an n-type characteristic and substituted with another dibenzofuran / dibenzothiophene moiety, And a dibenzofuran / dibenzothiophene moiety connected to the dibenzofuran / dibenzothiophene moiety.

For example, the organic compound may be represented by the following formula (1).

Formula 1

Wherein R ₁ to R ₁₅ are each independently selected from the group consisting of hydrogen, deuterium, tritium, silyl groups, C ₁ to C ₂₀ alkyl groups, C ₁ to C ₂₀ alkoxy groups, C ₁ to C ₂₀ alkylamine groups, C ₅ ~ C ₃₀ Homo aryl group, C ₄ ~ C ₃₀ heteroaryl group, C ₅ ~ C ₃₀ Homo alkylaryl group, C ₄ ~ C ₃₀ heteroaryl-alkyl aryl group, C ₅ ~ C ₃₀ Homo aryloxy group, C ₄ ~ C ₃₀ heteroaryloxy group, C ₅ ~ C ₃₀ Homo arylamine group, a C ₄ ~ C ₃₀ heteroaryl amine group, or adjacent groups unsubstituted or combined substituted each other C ₅ ~ C _30-homo-aryl group or a C ₄ ~ C ₃₀ heteroaryl group X and Y are each independently oxygen (O) or sulfur (S)

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

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

The organic compound of the present invention has bipolar characteristics because it has a carbazole moiety having p-type characteristics and at least one dibenzofuran or dibenzothiophene moiety having n-type characteristics, Excellent heat resistance.

The organic compound according to the present invention has a relatively wide band gap as compared with the retarded fluorescent material, and the triplet energy level is higher than the triplet energy of the retarded fluorescent material. Therefore, when the organic compound according to the present invention is used as a host of the light emitting material layer, the host exciton energy is efficiently transferred to the dopant, and the triplet / single-term exciton of the host or dopant and the hole (or electron) Exciton quenching by interaction is minimized. Accordingly, the lifetime of the light emitting diode device can be prevented from being lowered by electro-oxidation and photo-oxidation, so that a long-life light emitting device can be realized.

In addition, since the organic compound of the present invention can efficiently transfer energy to the dopant without losing energy in the light emission process, high luminous efficiency can be achieved.

Accordingly, an organic light emitting diode having improved luminescence efficiency and device lifetime characteristics by using the organic compound of the present invention as a host of an organic light emitting layer constituting an organic light emitting diode and using a compound exhibiting delayed fluorescence characteristics as a dopant, Can be manufactured.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic diagram for explaining a luminescent mechanism of a retarded fluorescent compound used together with an organic compound according to an exemplary embodiment of the present invention. Fig.
2 is a schematic diagram for explaining a relationship between energy levels between a host and a dopant in relation to a light emitting mechanism occurring in a light emitting material layer using a retardation light dopant and an organic compound of the present invention as a host according to an exemplary embodiment of the present invention .
3 is a cross-sectional view schematically showing 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. For example, the organic compound according to the present invention is used in a layer of a light emitting material.
4 is a cross-sectional view schematically showing 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, and is a schematic cross-sectional view of an organic light emitting diode having a charge blocking layer. For example, the organic compound according to the present invention is used in a layer of a light emitting material.
5 is a cross-sectional view schematically showing an organic light emitting diode display device as an example of a light emitting 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.

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

[Organic compounds]

The organic compound used in the organic light-emitting diode has excellent luminescence characteristics and it is necessary to maintain stable characteristics by driving the device. The organic compound according to the present invention has such a characteristic. In the organic compound according to the present invention, the organic compound according to the present invention can be represented by the following formula (1).

Formula 1

Wherein R ₁ to R ₁₅ are each independently selected from the group consisting of hydrogen, deuterium, tritium, silyl groups, C ₁ to C ₂₀ alkyl groups, C ₁ to C ₂₀ alkoxy groups, C ₁ to C ₂₀ alkylamine groups, C ₅ ~ C ₃₀ Homo aryl group, C ₄ ~ C ₃₀ heteroaryl group, C ₅ ~ C ₃₀ Homo alkylaryl group, C ₄ ~ C ₃₀ heteroaryl-alkyl aryl group, C ₅ ~ C ₃₀ Homo aryloxy group, C ₄ ~ C ₃₀ heteroaryloxy group, C ₅ ~ C ₃₀ Homo arylamine group, a C ₄ ~ C ₃₀ heteroaryl amine group, or adjacent groups unsubstituted or combined substituted each other C ₅ ~ C _30-homo-aryl group or a C ₄ ~ C ₃₀ heteroaryl group X and Y are each independently oxygen (O) or sulfur (S)

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

As used herein, the substituent in the term "substituted" includes, for example, a C ₁ -C ₂₀ alkyl group which is unsubstituted or substituted by halogen, a C ₁ -C ₂₀ alkoxy group which is unsubstituted or substituted by halogen, halogen, cyano group, -CF _3, a hydroxy group, a carboxy group, a carbonyl group, an amine group, C ₁ ~ C ₁₀ alkyl substituted amine group, C ₅ ~ C ₃₀ aryl substituted amine group, a C ₄ ~ C ₃₀ heteroaryl group substituted with an amine group, a nitro group, a hydrazide chewy a C ₁ to C ₂₀ alkylsilyl group, a C ₁ to C ₂₀ alkoxysilyl group, a C ₃ to C ₃₀ cycloalkylsilyl group, a C ₅ to C ₃₀ arylsilyl group, a C ₄ to C ₃₀ silyl group, A C ₅ -C ₃₀ aryl group, a C ₄ -C ₃₀ heteroaryl group, and the like, but the present invention is not limited thereto. For example, when R ₁ to R ₁₅ in the general formula (1) are substituted with an alkyl group, the alkyl group may be a linear or branched C ₁ to C ₂₀ , preferably C ₁ to C ₁₀ alkyl group.

The terms "heteroaromatic ring", "heterocycloalkylene group", "heteroarylene group", "heteroarylalkylene group", "heteroaryloxylene group", "heterocycloalkyl group", "heteroaryl group", " The term "hetero" as used in heteroarylalkyl group, heteroaryloxyl group and heteroarylamine group means that at least one of the carbon atoms constituting these aromatic or alicyclic rings, Means that one to five carbon atoms are replaced by one or more heteroatoms selected from the group consisting of N, O, S, and combinations thereof.

As shown in formula (I), the organic compound according to the present invention can be prepared by reacting a carbazole moiety (a moiety substituted with R ₁ to R ₈ ) with at least two dibenzofuran or dibenzothiophene moieties Tee (a moiety with X and Y). Hereinafter, for convenience of description herein, the central dibenzofuran / dibenzothiophene moiety directly connected to the carbazole moiety is referred to as the first dibenzofuran / dibenzothiophene moiety, and the first The side dibenzofuran / dibenzothiophene moiety connected to the dibenzofuran / dibenzothiophene moiety is referred to as the second dibenzofuran / dibenzothiophene moiety.

At this time, since the carbazole moiety has a p-type property because of its excellent ability to bond with holes, and the first and second dibenzofuran / dibenzothiophene moieties have relatively good bonding ability with electrons type characteristics. Therefore, the organic compound represented by Formula 1 may have bi-polar properties.

In one exemplary embodiment, R ₁ to R ₁₅ each independently may be hydrogen, deuterium, or tritium. In another exemplary embodiment, R ₁ to R ₁₅ are each independently a C ₁ to C ₂₀ , preferably C ₁ to C ₂₀ straight or branched chain alkyl group or C ₁ to C ₂₀ , preferably C ₁ to C ₂₀ Alkoxy group.

In another exemplary embodiment, R ₁ to R ₁₅ each independently may be an aromatic substituent. For example, when R ₁ to R ₁₅ are C ₅ to C ₃₀ homoaryl groups, R ₁ to R ₁₅ each independently represent a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, an anthracenyl group, a pentanenyl group, A benzenesulfonyl group, a benzenesulfonyl group, an azulenyl group, a pyrenyl group, a fluoranethenyl group, a benzenesulfonyl group, a benzenesulfonyl group, a benzenesulfonyl group, Condensation such as a triphenylene group, a triphenyl group, a triphenyl group, a triphenyl group, a triphenyl group, a triphenyl group, a triphenyl group, a triphenyl group, a triphenyl group, a triphenyl group, Or may be a fused aryl group.

In an alternative embodiment, when R ₁ to R ₁₅ are C ₄ to C ₃₀ heteroaryl groups, R ₁ to R ₁₅ each independently represent a pyrrolyl group, a pyridinyl group, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group A thiazolyl group, a tetrazinyl group, an imidazolyl group, a pyrazolyl group, an indolyl group, an isoindolyl group, an indazolyl group, an indolizinyl group, a pyrrolidinyl group, a carbazolyl group, a benzocarbazolyl group, A thiazolyl group, an indolocarbazolyl group, an indenocarbazolyl group, a benzofurocarbazolyl group, a benzothienocarbazolyl group, a quinolinyl group, an isoquinolinyl group, a phthalazinyl group, a quinoxalinyl group, , A quinazolinyl group, a quinolizinyl group, a quinolizinyl group, a purinyl group, a phthalazinyl group, a quinoxalinyl group, a benzoquinolinyl group, a benzoisoquinolinyl group, a benzoquinazolinyl group, a benzoquinoxalinyl group, , Phenanthrolinyl group, perimidinyl group, phenanthridinyl group, phthalidinyl group, cinol A thiazolyl group, a thiopyranyl group, a thiopyranyl group, a thiopyranyl group, a thiopyranyl group, a thiopyranyl group, a thiopyranyl group, a thiopyranyl group, a thiopyranyl group, A thiophene group, a benzothiophenyl group, a dibenzothiophenyl group, a difluoropyrazinyl group, a benzofurodibenzofuranyl group, A non-condensed or condensed heteroaryl group such as a benzothiophenyl group, a benzothienobenzofuranyl group, a benzothienodibenzofuranyl group, or an N-substituted spirobifluorenyl group.

In one exemplary embodiment, when R ₁ to R ₁₅ are a homoaryl group or a heteroaryl group, preferably these homoaryl or heteroaryl groups may be composed of one to three aromatic rings. When the number of the aromatic rings constituting R ₁ to R ₁₅ is increased, the conjugated structure in the entire organic compound becomes excessively long, so that the bandgap of the organic compound can be excessively reduced. For example, when R ₁ to R ₁₅ are aromatic substituents, R ₁ to R ₁₅ each independently represent a phenyl group, a biphenyl group, a pyrrolyl group, a triazinyl group, an imidazolyl group, a pyrazolyl group, a pyridinyl group, , A pyrimidinyl group, a pyridazinyl group, a furanyl group, a benzofuranyl group, a dibenzofuranyl group, a thiophenyl group, a benzothiophenyl group, a dibenzothiophenyl group or a carbazolyl group.

In another alternative embodiment, R ₁ to R ₁₅ may combine with adjacent groups to form a condensed ring which is unsubstituted or substituted with a C ₅ -C ₃₀ homoaryl group or a C ₄ -C ₃₀ heteroaryl group. When R ₁ to R ₁₅ combine with adjacent groups to form a condensed ring, the C ₅ to C ₃₀ homoaryl group or C ₄ to C ₃₀ heteroaryl group which may be substituted in the condensed ring is one or two aromatic rings Lt; / RTI > In this case, the organic compound represented by the general formula (1) may have a band gap energy suitable for use in the light emitting layer. Thus, when R ₁ to R ₁₅ combine with adjacent groups to form a condensed ring, the aromatic substituent which may be substituted in the newly formed condensed ring is preferably a phenyl group, a biphenyl group, a pyrrolyl group, an imidazolyl group, a pyrazolyl group, , A pyridinyl group, a pyrimidinyl group, a pyridazinyl group, a furanyl group or a thiophenyl group, preferably a phenyl group.

As described above, R ₁ to R ₁₅ may combine with adjacent groups to form a condensed ring which is unsubstituted or substituted with an aromatic ring. For example, when R ₁ to R ₈ constituting the carbazole moiety are each independently joined to adjacent groups to form a condensed ring, the carbazole moiety is not each substituted or a C ₁ to C ₂₀ linear or branched alkyl group, Preferably a C ₁ to C 10 linear or branched alkyl group, a C ₅ to C ₃₀ homoaryl group, preferably a C ₅ to C ₂₀ homoaryl group (for example, a phenyl group and / or a naphthyl group), a C ₄ to C ₃₀ heteroaryl Substituted with at least one functional group selected from the group consisting of a C ₄ -C ₂₀ heteroaryl group (for example, a pyridyl group, a pyrimidyl group and / or a carbazolyl group), and combinations thereof, A benzocarbazole moiety, a benzocarbazole moiety, a dibenzocarbazole moiety, a benzofurocarbazole moiety, a benzothienocarbazole moiety, an indenocarbazole moiety, Indolocarbazole (i ndolocarbazole moiety, and the like, but the present invention is not limited thereto.

On the other hand, when R ₉ to R ₁₅ constituting the second dibenzofuran / dibenzothiophene moiety are combined with adjacent groups to form a condensed ring, the second dibenzofuran / dibenzothiophene moiety is substituted Or a C ₁ to C ₂₀ linear or branched alkyl group, preferably a C ₁ to C ₁₀ straight or branched chain alkyl group, a C ₅ to C ₃₀ homoaryl group, preferably a C ₅ to C ₂₀ homoaryl group And / or a naphthyl group), a C ₄ -C ₃₀ heteroaryl group, preferably a C ₄ -C ₂₀ heteroaryl group (for example, a pyridyl group, a pyrimidyl group and / or a carbazolyl group) A pyridodibenzofuran moiety substituted with at least one functional group selected from the group consisting of pyridodibenzothiophene moiety, indenodibenzofuran moiety, indenodibenzofuran moiety, Indenodibenzothiophene Tea, Lodi indole-benzofuran (indolodibenzofuran) moiety, and / or indole-Lodi benzothiophene can form a (indolodibenzothiophene) moieties such as, but not the present invention is not limited to this.

The organic compound represented by the formula (1) has a carbazole moiety having a p-type characteristic and a dibenzofuran or dibenzothiophene moiety having an n-type characteristic, and thus has an excellent affinity for holes and electrons Do. Therefore, when the organic compound represented by the general formula (1) is applied to the light emitting layer of the light emitting diode, a recombination zone in which holes and electrons form an exciton forms a light emitting material layer (EML) - an electron transporting layer (ETL) ), But in the central region of the light emitting material layer (EML).

The organic compound represented by the formula (1) includes a carbazole moiety and a dibenzofuran / dibenzothiophene moiety, each of which has a six-membered ring connected to both sides of a central five-membered ring. These carbazole moieties, dibenzofuran / dibenzothiophene moieties have a strong chemical structure and are excellent in heat resistance. Therefore, the organic compound represented by Chemical Formula 1 is not deteriorated by Joule heat generated when the organic light emitting element is driven. Therefore, it can be applied to a light emitting device to realize excellent light emitting efficiency, and device breakdown can be prevented, thereby improving the device life.

In particular, the organic compound represented by the formula (1) has dibenzofuran / dibenzothiophene moieties each having a six-membered ring condensed on both sides of a five-membered ring. Accordingly, the HOMO energy level and the LUMO energy level of the organic compound represented by the formula (1) may be suitable for use as the material of the light emitting layer, for example, as a host of the light emitting layer. Particularly, when used with a retardation fluorescent material as described later, the driving voltage of the light emitting element can be lowered to reduce power consumption. Accordingly, the stress applied to the driving device due to the increase in the driving voltage is reduced, thereby improving the luminous efficiency and increasing the lifetime of the device.

 Therefore, the organic compound according to the present invention can be used as a host of an organic light emitting layer constituting an organic light emitting diode, and can be applied to a light emitting material layer using a so-called delayed florescence compound as a dopant. Explain.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic diagram for explaining a luminescent mechanism of a retarded fluorescent compound used together with an organic compound according to an exemplary embodiment of the present invention. Fig. Delayed fluorescence can be classified into thermally activated delayed fluorescence (TADF) and field-activated delayed fluorescence (FADF), wherein triplet excitons are activated by heat or an electric field, So-called super-fluorescence exceeding the maximum luminous efficiency in the material can be realized.

That is, the retarded fluorescent compound is activated by the heat or electric field generated when the device is driven, so that the triplet exciton is also involved in the emission of the triplet exciton. Generally, a retarded fluorescent compound has both an electron donor moiety and an electron acceptor moiety so that an intramolecular charge transfer (ICT) state is possible. When a retarded fluorescent compound capable of ICT state is used as a dopant, an exciton having a singleton energy level (S ₁ ) and an exciton having a triplet energy level (T ₁ ) in a retarded fluorescent compound migrate to an intermediate ICT state, (S ₁ → ICT ← T ₁ ) to the ground state (S ₀ ). Since both the exciton having the singlet energy level (S ₁ ) and the exciton having the triplet energy level (T ₁ ) participate in the light emission, the internal quantum efficiency is improved and thus the light emission efficiency is improved.

Conventionally, since the fluorescent material has a highest occupied molecular orbital (HOMO) and a lowest unoccupied molecular orbital (LUMO) distributed throughout the molecule, It is impossible to switch between them (selection rule). However, since the compound having ICT state has a small overlap of HOMO and LUMO orbitals, the interaction between the HOMO state orbit and the LUMO state orbit is small. Therefore, the spin state change of the electrons does not affect other electrons, and a new charge transfer band (CT band) which does not follow the selection rule is formed.

In other words, since the electron acceptor moiety and the electron donor moiety are spaced apart in the molecule in the retarded fluorescent compound, the dipole moment in the molecule is present in a highly polarized state. The interaction between the HOMO and the LUMO state orbitals is reduced in the state where the dipole moment is polarized, and the transition from the triplet state to the intermediate state (ICT) becomes possible, and the exciton of the singlet energy level (S ₁ ) Of course, all of the excitons of the triplet energy level (T ₁ ) participate in luminescence. 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% are converted into an intermediate state (ICT) Since the light emission occurs while falling back to the ground state S ₀ , the internal quantum efficiency is theoretically 100%.

The dopant and the host for implementing the delayed fluorescence need to have the following characteristics. The retarded fluorescent dopant must have an electron donor moiety and an electron acceptor moiety at the same time in one molecule, so that ICT can be realized. That is, in an ICT complex under certain conditions, one electron moves from the electron donor moiety to the electron acceptor moiety, resulting in the separation of charge in the molecule. In order to cause energy transfer in both the triplet state and the singlet state, the dopant capable of realizing retarded fluorescence has a difference (ΔE _ST ) between the singlet energy level (S ₁ ) and the triplet energy level (T ₁ ) of 0.3 eV, for example between 0.05 and 0.3 eV. In this way, compounds with low ΔE _ST exhibit fluorescence not only when inter-system crossing (ICS) occurs in which energy is transferred from a singlet state to a triplet state, but when heat energy at a room temperature level is applied, Reverse Inter System Crossing (RISC) occurs in a single energy state with a higher energy, and a delayed fluorescence is exhibited as a single phase state transitions to a bottom state. In the case of delayed fluorescence, efficiency of 100% at the theoretical maximum can be obtained, so that the internal quantum efficiency equivalent to that of a conventional phosphorescent material containing a heavy metal can be realized.

On the other hand, the host for implementing the delayed fluorescence should be able to induce excitons in the triplet state in the dopant to be involved in light emission without being quenched (non-quenching). Fig. 2 is a schematic diagram for explaining the relationship between energy levels between a host and a dopant when an organic compound according to an exemplary embodiment of the present invention is used as a host with a retardation fluorescent dopant. Fig.

As shown in FIG. 2, the host for implementing the delayed fluorescence has to adjust the energy level with the dopant. First, the excited state triplet energy level (T ₁ ^H ) of the host and the excited single-energy level (S ₁ ^H ) of the excited state of the host are respectively the excited triplet energy level (T ₁ ^D ) Should be higher than the energy level (S ₁ ^D ). The excited state triplet energy level (T ₁ ^H ) of the host and the excited single harmonic energy level (S ₁ ^H ) of the host are coupled to the excited triplet energy level (T ₁ ^D ) of the retarded fluorescent dopant and the excited single- ₁ ^D ), the excitation state of the excited triplet energy level (T ₁ ^D ) of the retarded fluorescent dopant causes a reverse-charge shift of the host to the excited triplet energy level (T ₁ ^H ) of the host, The triplet exciton of the retarded fluorescent dopant does not contribute to the luminescence since the triplet exciton is non-luminescent disappearing in the host where the triplet exciton can not emit light. In one exemplary embodiment, the singlet energy level (S ₁ ^H ) of the organic compound represented by formula ( ₁ ) may be greater than or equal to 2.8 eV, and the triplet energy level (T ₁ ^H ) may be greater than or equal to 2.6 eV.

In addition, it is necessary to appropriately adjust the highest occupied molecular orbital (HOMO) energy level and the lowest unoccupied molecular orbital (LUMO) energy level of the host and the retardation fluorescent dopant. For example, the difference between the highest level occupied molecular orbital energy level (HOMO ^H ) of the host and the highest level occupied molecular orbital energy level (HOMO ^D ) of the retarded fluorescent dopant (| HOMO ^H -HOMO ^D | The difference (| LUMO ^H -LUMO ^D |) between the molecular orbital energy level (LUMO ^H ) and the lowest level non-occupied molecular orbital energy level (LUMO ^D ) of the retardation fluorescent dopant is 0.5 eV or less, for example, 0.1 to 0.5 eV May be preferred. As a result, the charge transfer efficiency from the host to the retarded fluorescent dopant is improved, and ultimately the luminous efficiency can be improved. For example, the highest level occupied molecular orbital energy level (HOMO ^H ) of the organic compound represented by the formula (1) may be -5.8 eV or less.

In addition, in order to ensure a sufficient lifetime of the light emitting device to which the retardation fluorescent dopant is applied, a single or triplet exciton of the dopant and an exciton quenching (exciton quenching) caused by the interaction of the peripheral hole- ) To minimize electro-oxidation and / or photo-oxidation.

When a host applied to the conventional organic light emitting layer is used, a recombination zone where electrons and holes migrate from the respective electrodes to form excitons is formed between the light emitting material layer (EML 260, see FIG. 4) and the electron transporting layer ETL 270, see FIG. 4) or a hole blocking layer (HBL 265, see FIG. 4).

As described above, when a retarding fluorescent dopant is used, the triplet exciton of the retarding fluorescent dopant also contributes to light emission. Therefore, when the recombination region forming the exciton is formed at the interface between the light emitting material layer and the electron transporting layer / hole blocking layer, the possibility of the triplet exciton and the hole-polarron of the retardation fluorescent dopant meeting and interacting with each other is increased. Due to the interaction of the triplet exciton and the hole-polaron of the retarded fluorescent dopant, the triplet energy of the retarded fluorescent dopant does not contribute to the luminescent mechanism and is non-luminescent. When the non-emission disappearance is increased, stress applied to the material applied to the organic light emitting layer causes damage, thereby reducing the lifetime of the device.

On the other hand, according to the present invention, the organic compound represented by formula (1) is a bipolar organic compound having both a p-type moiety and an n-type moiety. According to an exemplary embodiment of the present invention, when the organic compound of the present invention is used as a host of an organic light emitting layer, a recombination region where holes and electrons meet to form an exciton is not an interface between the light emitting material layer and the adjacent light emitting layer, Lt; / RTI > layer. As a result, the probability of the triplet exciton of the dopant to meet and interact with the hole-polaron is reduced, and the triplet excitons are not non-luminescent annihilated due to their interaction. Therefore, the damage to the light emitting material caused by the non-emission disappearance of the light emitting material is prevented, and the lifetime of the device is prevented from being reduced due to the damage of the light emitting material.

In addition, since the organic compound according to the present invention is an amphoteric compound, the triplet energy level (T ₁ ^H ) and the singlet energy level (S ₁ ^H ) of the excited state are high, Do. That is, when the organic compound according to the present invention is used as a host for the organic light emitting layer, the exciton of the excited triplet energy level (T ₁ ^D ) of the retarded fluorescent dopant is inversely related to the triplet energy level (T ₁ ^H ) The charge transfer is suppressed and the non-emission extinction of the triplet exciton is suppressed in the host, so that the triplet state exciton of the retardation fluorescent dopant can contribute to the light emission and improve the light emission efficiency.

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

Formula 2a

2b

(In the formulas (2a) and (2b), R ₁ to R ₁₅ , X and Y are each the same as defined in formula (1)

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

(3)

The organic compound represented by the general formula (2a), (2b) or (3) is bonded to the center first dibenzofuran / dibenzothiophene moiety, and the carbazole moiety having p-type characteristics and the first dibenzofuran / A second dibenzofuran / dibenzothiophene moiety having an n-type characteristic is bonded asymmetrically, which is bonded to the benzothiophene moiety. Namely, the carbazole moiety and the carbazole moiety having the p-type characteristic and the benzene ring having the side chain constituting the second dibenzofuran / dibenzothiophene moiety, The benzofuran / dibenzothiophene moiety is introduced to the asymmetric position, and the amorphous property is more exerted to improve the heat resistance property. Accordingly, the crystallization caused by Joule heat generated when driving the organic light emitting device is prevented, and the structure of the organic light emitting device is not destroyed.

In addition, since it has a carbazole moiety having two benzene structures linked by a five-membered ring and a dibenzofuran / dibenzothiophene moiety, the HOMO / LUMO energy level Lt; / RTI > In particular, when used in combination with a retarded fluorescent dopant, the exciton energy can be transferred to the retarded fluorescent dopant without energy loss during the light emission process.

That is, when the organic compound represented by the general formula (2a), (2b) or (3) is used in the organic light emitting layer of the light emitting device, the light emitting efficiency can be improved. The exciton quenching due to the interaction between the host exciton and the surrounding polaron is minimized and the lifetime of the light emitting diode device due to electro-oxidation and photo-oxidation can be prevented from being lowered. In addition, the organic compound of the present invention is excellent in heat resistance, energy band gap and triplet energy level. When the organic compound of the general formula (2a), (2b) or (3) is used as a host of the light emitting material layer, energy can be efficiently transferred to the dopant, so that the light emitting efficiency of the light emitting device to which the organic compound of the present invention is applied can be improved. In addition, damage to the material applied to the light emitting material layer is reduced, so that a light emitting device with a long life can be manufactured, and a light emitting device having excellent color purity can be realized.

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

As described above, the organic compounds represented by the general formulas (1) to (3) are used as the light emitting material in the organic light emitting layer constituting the organic light emitting diode, so that the light emitting device having good color purity and improved light emitting efficiency and device life characteristics have. This will be described. 3 is a cross-sectional view schematically showing an organic light emitting diode in which an organic compound is applied to an organic light emitting layer according to an exemplary embodiment of the present invention.

3, 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, a first electrode 110 and a second electrode 110, And 120, respectively. In the exemplary embodiment, the organic light emitting layer 130 includes a hole injection layer (HIL) 140, a hole transfer layer (HTL) 150, and a light emitting material layer 140 sequentially stacked from the first electrode 110. 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 large work function value, for example, a transparent conductive oxide (TCO). For example, the first electrode 110 may be formed of indium-tin-oxide (ITO), indium-zinc-oxide (IZO), indium-tin- (ITO), tin oxide (SnO), zinc oxide (ZnO), indium-copper-oxide (ICO) and aluminum: Al: ZnO have.

The second electrode 120 may be a cathode for supplying electrons to the light emitting material layer 160. The second electrode 120 may have a reflective property such as a conductive material having a relatively low work function value, for example, aluminum (Al), magnesium (Mg), calcium (Ca), silver (Ag) It can be made of good material.

The hole injection layer 140 is located between the first electrode 110 and the hole transport layer 150 and improves the interface characteristics between the first electrode 110 as an inorganic material and the hole transport layer 150 as an organic material. In one exemplary embodiment, the hole injection layer 140 is formed of a mixture of 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'- NPB), 1,4,5,8,9,11-hexaazatriphenylene hexacarbonitrile (1, 4, 5, 8, 9, 11- hexaazatriphenylenehexacarbonitrile (HAT-CN), 1,3,5-tris [4- (diphenylamino) phenyl] benzene, 1,3,5- PEDOT / PSS) and / or N- (biphenyl-4-yl) -9,9-dimethyl-N- (4-ethylenedioxythiophene) polystyrene sulfonate (9-phenyl-9H-carbazol-3-yl) phenyl) -9H-fluorene- -phenyl-9H -carbazol-3-yl) phenyl) -9H-fluoren-2-amine) and the like. Depending on the characteristics of the organic light emitting diode 100, the hole injection layer 140 may be omitted.

The hole transport layer 150 is disposed adjacent to the light emitting material layer 160 between the first electrode 110 and the light emitting material layer 160. In one exemplary embodiment, the hole transport layer 150 is formed from N, N'-diphenyl-N, N'-bis (3-methylphenyl) -1,1'-biphenyl-4,4'- TPD), NPD, 4,4'-bis (N-carbazolyl) - N'-diphenyl- Bis (N-carbazolyl) -1,1'-biphenyl (CBP), 1,3-bis (N-carbazolyl) benzene -carbazolyl) benzene, 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- -yl) -N- (4- (9-phenyl-9H-carbazol-3-yl) phenyl) biphenyl-4-amine), but the present invention is not limited thereto.

The light emitting material layer 160 may be formed by doping a host with a dopant. For example, the light emitting material layer 160 may be doped with about 1 to 30% by weight of a dopant to the host, and may emit green light.

The organic compound represented by the general formulas (1) to (3) may be used as a host of the light emitting material layer 160. On the other hand, the dopant used for the light emitting material layer 160 may be a dopant having a retardation fluorescent property.

As described above, a compound having a retarded fluorescence characteristic is activated by heat or an electric field and has an intermediate energy state such as an ICT complex form. Both the exciton having the single-energy level and the exciton having the triplet energy level are involved in the light emission, so that the light-emitting efficiency of the organic light-emitting diode 100 can be improved.

2, when the difference (ΔE _ST ^D ) between the excited single-state energy level (S ₁ ^D ) and the excited triplet energy level (T ₁ ^D ) of the dopant is 0.3 eV or less, these energy levels To the intermediate energy state, and finally to the bottom state, the quantum efficiency of the dopant can be improved. That is, as ΔE _ST ^D becomes smaller, the luminous efficiency can be increased and the difference (ΔE _ST ^D ) between the excited single-state energy level (S ₁ ^D ) and the excited triplet energy level (T ₁ ^D ) eV, the singlet-state exciton and the triplet state exciton can be transferred to an intermediate ICT complex state by heat or an electric field.

In order to maximize the luminous efficiency due to the delayed fluorescence, the excited triplet energy level (T ₁ ^H , see FIG. 3) of the organic compound represented by the general formulas (1) to (3) Should be higher than the excited state triplet energy level of the compound (T ₁ ^D , see FIG. 3). In particular, the difference between the highest level occupied molecular orbital energy level (HOMO ^H ) of the host and the highest level occupied molecular orbital energy level (HOMO ^D ) of the dopant (| HOMO ^H -HOMO ^D |) or host's lowest level ratio occupied molecular orbital energy minimum level difference between the level unoccupied molecular orbital energy level (LUMO ^D) of (LUMO ^H) and dopant (| LUMO ^H -LUMO ^D |) is to not more than 0.5 eV, as a dopant in the host, energy is efficiently transmitted to the light-emitting efficiency Can be maximized.

According to one exemplary embodiment, when the organic compound represented by any one of Chemical Formulas 1 to 3 is used as a host of the light emitting material layer 160, a dopant suitable for the energy level with respect to the host may be used Lt; / RTI > For example, the retarded fluorescent dopant can be a retarded fluorescent dopant that emits blue light. To realize a level of blue emission applicable to a display device, the excited state single-energy level (S ₁ ^D ) of the retarded fluorescent dopant may be at a level of 2.7 to 2.75 eV, and the excited triplet energy level (T ₁ ^D ) may be at a level of 2.4 to 2.5 eV, but the present invention is not limited thereto.

The blue light-emitting retardant fluorescent dopant which can be used as a dopant of the light emitting material layer 160 according to the exemplary embodiment of the present invention may be made of any one material represented by the following formula (4).

Formula 4

In an exemplary embodiment, the retarded fluorescent dopant that may be used in the light emissive material layer 160 is 10- (4- (4,6-diphenyl-1,3,5-triazin-2-yl) phenyl) -9 9,9-dimethyl-9,9-dimethyl-9,10-dihydroacridine (10- (4- (4,6-diphenyl-1,3,5-triazin- (9,9-dimethyl-9,10-dihydroacridine), 10,10 '- (4,4'-sulfonylbis (9,9-dimethyl-9,10-dihydroacridine), DMAC-DPS), 10-phenyl-10H, 10'H (10-phenyl-10H, 10'H-spiro [acridine-9,9'-anthracen] -10'-one, ACRSA) 3,6-dibenzoyl-4,5-di (1-methyl-9-phenyl-9H-carbamoyl) -9-phenyl-9H-carbazoyl) -2-ethynylbenzonitrile, CzPVP), 9,9 ', 9 "- (5- (4,6- ) Benzene-1,2,3-triyl) tris (9,9 ', 9 "- (5- (4,6-diphenyl-1,3,5-triazin- -1,2,3-triyl) tris (9H-carbazole), TcZTrz), 9,9 '- (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 ', 9 ", 9 "' - ((6, 6-triazine-2,4-diyl) bis (9H-carbazole, DDczTrz), bis (4- (9H-3,9 ', 5'-triazin- (9H-3,9'-bicarbazol-9-yl) phenyl) methanone, CC2BP), 9 '- [4- (4,6- Phenyl] -3,3 ", 6,6" -tetraphenyl-9,3 ', 6', 9 "-torr-9H-carbazole ( 9 '- [4- (4,6-diphenyl-1,3,5-triazin-2-yl) phenyl] -3,3,6,6-tetraphenyl- -ter-9H-carbazole, BDPCC-TPTA), 9 '- [4- (4,6-diphenyl-1,3,5-triazin- 9 "-tetra-9H-carbazole (9 '- [4- (4,6-diphenyl-1,3,5-triazin- 9,9'- (4,4'-sulfonylbis (4,1-phenylene)) bis (3,6-dimethoxy-9H-carbazole) , 9 '- (4,4'-sulfonylbis (4,1-phenyle ne)) bis (3,6-dimethoxy-9H-carbazole), DMOC-DPS), 9- 3 ', 6'-diphenyl-9H-3,9'-bicarbazole (9- (4- (4,6-diphenyl-1,3,5-triazin- Diphenyl-9H-3,9'-bicarbazole, DPCC-TPTA), 10- (4,6-diphenyl- 1,3,5-triazin- (4,6-diphenyl-1,3,5-triazin-2-yl) -10H-phenoxazine, Phen-TRZ), 9- Phenyl) -9H-carbazole, Cab-Ph-TRZ) was obtained in the same manner as in Example 1, , 1,2,3,5-tetrakis (3,6-carbazol-9-yl) -4,6-dicyanobenzene (1,2,3,5-Tetrakis (3,6- 4,6-dicyanobenzene, 4CzIPN), 2,3,4,6-tetra (9H-carbazol-9-yl) -5-fluorobenzonitrile -carbazol-9-yl) -5-fluorobenzonitrile, 4CZFCN and / or 10- (4- (4,6-diphenyl-1,3,5-triazin- 9-fluorene] (10- (4- (4,6-diphenyl-1,3,5-triazin-2-yl) phenyl) -10H- spiro [acridine- 9'-fluorene], SpiroAC-TRZ), however, But it is not limited thereto this.

For example, the dopant, which may be a retardation fluorescent dopant, may be added in a proportion 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 forming the electron transport layer 170 requires high electron mobility and stably supplies electrons to the light emitting material layer 160 through smooth electron transport.

In one exemplary embodiment, the electron transporting layer 170 is formed from an imidazole oxadiazole, triazole, phenanthroline, benzoxazole, benzothiazole, ), Benzimidazole, triazine, and the like.

More specifically, the electron transport layer 170 is formed of tris (8-hydroxyquinoline aluminum) (Alq ₃ ), 2-biphenyl-4-yl-5- (4- 4-yl-5- (4-t-butylphenyl) -1,3,4-oxadiazole (PBD), spiro-PBD, lithium quinoline Phenyl quinolate (Liq), 2- [4- (9,10-di-2-naphthalenyl-2-anthracenyl) phenyl] (2-methyl-8-quinolinolato-N1, O8) - (1,1'-di-2-naphthalenyl-2-anthracenyl) phenyl] Biphenyl-4-olato) aluminum (BAlq), 3- (biphenyl-4-olato) aluminum 4-yl) -5- (4-tertbutylphenyl) -4-phenyl-4H-1,2,4- -4H-1,2,4-triazole (TAZ), 4,7-diphenyl-1,10-phenanthroline (Bphen), tris (phenylquinoxaline) (tris (phenylquinoxaline) (TPQ), and / or 1,3,5-tri (N- phenyl-benzimidazol-2-yl) benzene (1,3,5-tris (N-phenylbenzimiazole-2-yl) benzene; TPBi) it is formed of a like, but the present invention is not limited thereto.

The electron injection layer 180 is located between the second electrode 120 and the electron transport layer 170 and improves the characteristics of the second electrode 120 to improve the lifetime of the device. In one exemplary embodiment, the material of the electron injection layer 180 may be an alkali halide based material such as LiF, CsF, NaF, BaF ₂ , and / or lithium quinolate (Liq), lithium benzoate, An organic metal-based 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 a retardation fluorescent property in the light emitting material layer 160 constituting the organic light emitting layer 130. [ Since both the singlet energy state and the triplet energy state excitons are involved in the light emission, the light emission 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 the general formulas (1) to (3) have bonding and transporting properties to both holes and electrons. The organic compounds represented by the general formulas (1) to (3) have a high excited triplet energy level (T ₁ ^H ). When the organic compound represented by any one of Chemical Formulas 1 to 3 is used as the host of the light emitting material layer, recombination regions where electrons and holes meet to form excitons are formed at the center of the light emitting material layer, not at the interface between the light emitting material layer and the electron transporting layer do. Accordingly, exciton quenching due to the interaction between the triplet exciton of the dopant and the surrounding hole-polaron is minimized, and the lifetime of the light emitting diode device due to the electro-oxidation and photo-oxidation can be prevented have. The damage to the light emitting material caused by the non-emission disappearance is reduced, and the organic compounds represented by the general formulas (1) to (3) have excellent heat resistance characteristics, so that the lifetime of the device can be improved. It has a substituent group of a strong condensed aromatic ring and has high thermal stability and can efficiently transfer energy to other molecules without energy loss during the light emission process. Accordingly, it is possible to realize the light emitting diode 100 having improved luminous efficiency, improved device life, and good color purity by using the organic compound represented by Chemical Formula 1 to Chemical Formula 3 in the light emitting layer.

Meanwhile, the organic light emitting diode according to the present invention may further include at least one exciton blocking layer. 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. 4, the organic light emitting diode 200 according to the second embodiment of the present invention includes a first electrode 210 and a second electrode 220 facing each other, a first electrode 210 and a second electrode 210 And 220, respectively.

In the exemplary embodiment, the organic light emitting layer 230 includes a hole injection layer 240, a hole transport layer 250, a light emitting material layer 260, an electron transport layer 270, and an electron transport layer 270 sequentially stacked from the first electrode 210. And an injection layer 280. The organic light emitting layer 230 may include an electron blocking layer (EBL) 255 and / or a light emitting material layer 260, which is a first exciton blocking layer positioned between the hole transporting layer 250 and the 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 and the electron transport layer 270.

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

The hole injection layer 240 is located between the first electrode 210 and the hole transport layer 22. The hole injection layer 240 may include at least one of MTDATA, CuPc, TCTA, NPB, HAT-CN, TDAPB, PEDOT / PSS and / Phenyl) -9H-fluorene-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 adjacent to the light emitting material layer 260 between the first electrode 210 and the light emitting material layer 260. The hole transport layer 250 is formed of TPD, NPD, CBP, mCP, N- (biphenyl-4-yl) -9,9- Phenyl) -9H-fluorene-2-amine and / or N- (biphenyl-4-yl) -N- 4-amine. ≪ / RTI >

The light emitting material layer 260 may be formed by doping a host with a dopant. As an example, the light emitting material layer 260 may be doped with about 1 to 50% by weight of a dopant to the host, and may emit blue light. For example, when the organic compound represented by any one of Chemical Formulas 1 to 3 is used as a host of the light emitting material layer 260 and a compound exhibiting delayed fluorescence properties, for example, any compound represented by Chemical Formula 4, for example, DMAC- TRZ, DMAC-DPS, ACRSA, Cz-VPN, TcZTrz, DczTrZ, DDczTrZ, CC2BP, BDPCC-TPTA, BCC-TPTA, DMOC-DPS, DPCC- A compound such as SpiroAC-TRZ can be used as a dopant.

The electron transport layer 270 is located between the light emitting material layer 260 and the electron injection layer 280. For example, the electron transport layer 270 may be formed of a material selected from the group consisting of imidazole, oxadiazole, triazole, phenanthroline, benzoxazole, benzothiazole, Triazole, triazole, and the like. For example, the electron transport layer 270 can be formed of Alq ₃ , PBD, spiro-PBD, Liq, 2- [4- (9,10- Phenyl-1H-benzimidazole, BAlq, TAZ, Bphen, TPQ, and / or TPBi, but the present invention is not limited thereto.

The electron injection layer 280 is located between the second electrode 220 and the electron transport layer 270. As the material of the electron injection layer 280, an organic metal-based material such as an alkali halide-based material such as LiF, CsF, NaF, BaF ₂ and / or Liq, lithium benzoate), sodium stearate, But is not limited thereto.

On the other hand, when the holes move to the second electrode 220 through the light emitting material layer 260 or electrons travel to the first electrode 210 through the light emitting material layer 260, Can be imported. In order to prevent this, the organic light emitting diode 200 according to the second exemplary embodiment of the present invention includes at least one exciton blocking layer adjacent to the light emitting material layer 260.

For example, the organic light emitting diode 200 according to the second embodiment of the present invention includes an electron blocking layer (not shown) capable of controlling the movement of electrons between the hole transport layer 250 and the light emitting material layer 260, layer, EBL, 255).

More specifically, the electron blocking layer 255 may be formed of a material selected from the group consisting of TCTA, tris [4- (diethylamino) phenyl] amine, N- (biphenyl- Phenyl-9H-fluorene-2-amine, tri-p-tolylamine, Bis (4- (N, N'-di (ptolyl) amino) phenyl) cyclohexane (1,1- ; TAPC), MTDATA, mCP, 3,3'-bis (N-carbazolyl) -1,1'-biphenyl, mCBP) , TPD, CuPC, N, N'-bis [4- [bis (3-methylphenyl) amino] phenyl] -N, N'-diphenyl- [ (N, N'-bis [4- [bis (3-methylphenyl) amino] phenyl] -N, N'- diphenyl- [1,1'- biphenyl] -4,4'- diamine DNTPD) and / or TDAPB and the like.

A hole blocking layer 265 is disposed as a second exciton blocking layer between the light emitting material layer 260 and the electron transporting layer 270 to prevent movement of holes between the light emitting material layer 260 and the electron transporting layer 270. do. In one exemplary embodiment, the material of the electron transport layer 270 may be imidazole, oxadiazole, triazole, phenanthroline, Benzoxazole, benzothiazole, benzimidazole, triazine and the like can be used.

For example, the hole blocking layer 265 has a higher occupied molecular orbital (HOMO) energy level than the material used for the light emitting material layer 260, 4-diphenyl-1,10-phenanthroline (BCP), BAlq, Alq3, PBD, spiro-PBD, Liq and / or bis- Bis-4,6- (3,5-di-3-pyridylphenyl) -2-methylpyrimidine (B3PYMPM) have.

Since the organic light emitting diode 200 according to the second embodiment of the present invention has the dopant having the retardation fluorescence characteristic in the light emitting material layer 260, the light emitting efficiency is improved. In addition, the light emitting material layer 260 includes a host made of the organic compound represented by the general formulas (1) to (3).

The organic compounds represented by the general formulas (1) to (3) are amphoteric compounds, and the triplet energy level is high. When the organic compound represented by the general formulas (1) to (3) is used in the light emitting layer, a recombination region in which electrons and holes meet to form an exciton is formed at the center of the light emitting material layer. Accordingly, exciton quenching due to the interaction between the triplet exciton of the dopant and the surrounding hole-polaron is minimized, and the lifetime of the light emitting diode device due to the electro-oxidation and photo-oxidation can be prevented have. In addition, the organic compound of the present invention not only has a high triplet energy level, but also has high thermal stability and can efficiently transfer energy to other molecules without energy loss during the light emission process. Accordingly, by using the organic compound represented by any one of Chemical Formulas 1 to 3 in the light emitting layer, it is possible to realize the light emitting diode 200 having improved luminous efficiency, improved device life, and good color purity.

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 charge transporting layer 250 and 270 adjacent to the light emitting material layer 260, It is possible to further improve the luminous efficiency and the device life of the organic light emitting diode 200. [0070]

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

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 an organic light emitting diode 400 connected to a driving thin film transistor Td as a driving element. The driving thin film transistor Td includes a semiconductor layer 310, a gate electrode 330, a source electrode 352 and a drain electrode 354. In FIG. 3, the driving thin film transistor Td includes a driving thin film of a coplanar structure And a transistor Td.

The substrate 302 may be a glass substrate, a thin flexible substrate, or a polymeric plastic substrate. For example, the flexible substrate may be formed of a material such as polyimide (PI), polyethersulfone (PES), polyethylene naphthalate (PEN), polyethylene terephthalate (PET) and polycarbonate (PC) As shown in FIG. The driving thin film transistor Td as the driving element and the substrate 302 on which the organic light emitting diode 400 is located constitute an array substrate.

A semiconductor layer 310 is formed on the substrate 302. For example, the semiconductor layer 310 may be made of an oxide semiconductor material. In this case, a light shielding pattern (not shown) and a buffer layer (not shown) may be formed under the semiconductor layer 310. The light shielding pattern prevents light from being incident on the semiconductor layer 310, Thereby preventing deterioration of the semiconductor device. Alternatively, the semiconductor layer 310 may be formed of polycrystalline silicon. In this case, impurities may be doped on both edges of the semiconductor layer 310.

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. A gate insulating film 320 may be formed of an inorganic insulating material such as silicon oxide (SiO ₂₎ or silicon nitride (SiNx).

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

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

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

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

The source electrode 352 and the drain electrode 354 are spaced apart from each other around the gate electrode 330 and connected to both sides of the semiconductor layer 310 through the first and second semiconductor layer contact holes 342 and 344, Contact. Although not shown, the data wiring extends along the second direction and intersects the gate wiring to define the pixel region, and the power wiring for supplying the high potential voltage is located apart from the data wiring. The second capacitor electrode is connected to the drain electrode 354 and overlaps the first capacitor electrode to form a storage capacitor with the dielectric layer between the first and second capacitor electrodes as a dielectric layer.

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

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

The organic light emitting diode display 300 may include a color filter (not shown) for absorbing light generated in the organic light emitting diode 400. For example, a color filter (not shown) can absorb red (R), green (G), blue (B), and white (W) light. In this case, color filter patterns of red, green, and blue that absorb light may be formed separately for each pixel region, and each of the color filter patterns may include an organic light emitting diode (OLED) 400 and the organic light emitting layer 430 in the organic light emitting layer 400. By adopting a color filter (not shown), the organic light emitting diode display 300 can realize full-color.

For example, when the organic light emitting diode display 300 is a bottom emission type, a color filter (not shown) for absorbing light may be disposed on the interlayer insulating layer 340 corresponding to the organic light emitting diode 400 . In an alternative embodiment, if the organic light emitting diode display 300 is a top emission type, the color filter may be located on top of the organic light emitting diode 400, i.e., above the second electrode 420.

A planarization layer 360 is formed on the entire surface of the substrate 302 over the source electrode 352 and the drain electrode 354. The planarization layer 360 has a flat upper surface and a drain contact hole 362 that exposes the drain electrode 354 of the driving thin film transistor Td. Here, the drain contact hole 362 is formed directly on the second semiconductor layer contact hole 344, but may be formed apart from the second semiconductor layer contact hole 344.

The light emitting diode 400 includes a first electrode 410 located on the planarization layer 360 and connected to the drain electrode 354 of the driving TFT Td, A light emitting layer 430 and a second electrode 420.

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

Meanwhile, when the organic light emitting diode display device 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.

A bank layer 370 covering the 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 region.

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. Alternatively, as shown in FIGS. 3 to 4, the organic light emitting layer 430 may include a hole injection layer, a hole transport layer, an electron blocking layer, a light emitting material layer, a hole blocking layer, an electron transporting layer, and / Of the organic layer.

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 disposed on the front surface of the display region and is made of a conductive material having a relatively small work function value and can be used as a cathode. For example, the second electrode 420 may be formed of any one of an alloy or a combination thereof such as aluminum (Al), magnesium (Mg), calcium (Ca), silver (Ag), or aluminum- .

An encapsulation film 380 is formed on the second electrode 420 to prevent external moisture from penetrating into the organic light emitting diode 400. The encapsulation film 380 may have a laminated 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, the light emitting efficiency is improved. Further, 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 formulas (1) to (3) are amphoteric compounds. When the organic compound represented by Chemical Formulas 1 to 3 is used for the light emitting material layer, a recombination region where electrons and holes meet to form an exciton is formed at the center of the light emitting material layer. The exciton quenching due to the interaction between the triplet exciton of the dopant and the surrounding hole-polaron is minimized, and the lifetime of the light emitting diode device can be prevented from being lowered. Further, the organic compound of the present invention has a high excited triplet energy level (T ₁ ^H ). Accordingly, by applying the organic compounds represented by Chemical Formulas 1 to 3 to the organic light emitting layer 430, it is possible to improve the color purity and the light emitting efficiency of the organic light emitting diode 400 and the organic light emitting diode display 300, Can be improved.

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, 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 intermediate 1-1

Under nitrogen, 10 g (40.65 mmol) of 4-bromo dibenzofuran, 5.1 g (20.32 mmol) of iodine and 6.6 g (20.32 mmol) of phenyl iodide diacetate were placed in a mixture of 150 mL of acetic acid and 150 mL of acetic anhydride and three drops of sulfuric acid After that, the mixture was stirred at room temperature for 10 hours. After completion of the reaction, ethyl acetate is added to the mixed solution, followed by washing with water, followed by layer separation. Anhydrous magnesium sulfate is added to the organic layer and stirred. The mixture was filtered through a silica pad, and the filtrate was concentrated under reduced pressure to give a column. Intermediate 1-1 was obtained in a yield of 65%.

2) Synthesis of intermediate 1-2

2.2 g (13.18 mmol) of carbazole, 2 g (32.53 mmol) of copper powder and 3.6 g (26.35 mmol) of potassium carbonate are added to 70 mL of dimethyl acetoamide and the mixture is stirred at 130 ° C for 24 hours. After cooling to room temperature, the mixture is filtered through a silica pad to remove copper powder. The resulting solution is washed with water, and then anhydrous magnesium sulfate is added to the organic layer. After filtration through a silica pad, the solution was concentrated under reduced pressure to give a column, and intermediate 1-2 was obtained in 78% yield.

3) Synthesis of compound 1

Intermediate 1-2 8.4g (20.43 mmol), dibenzo [b, d] furan-4-ylboronic acid 4.76g (22.47 mmol), Tetrakis (triphenylphosphine) palladium (Pd (PPh 3) 4) 2 mol% of tetrahydrofuran 50 mL And 40.86 mmol of potassium carbonate are dissolved in 25 mL of water and mixed. After stirring at 80 ° C for 12 hours, the reaction is terminated and the mixture is cooled to room temperature to separate the water and the organic layer. Anhydrous magnesium sulfate is added to the organic layer and stirred. After filtration through a silica pad, the solution was concentrated under reduced pressure to obtain a compound 1 in a yield of 60%.

Synthesis Example 2: Synthesis of Compound 2

The reaction and purification were carried out in the same manner as in the synthesis of the compound 1 except that 4.76 g (22.47 mmol) of the intermediate 1-2 and dibenzo [b, d] furan-1-ylboronic acid were used and 57% To give compound 2.

Synthesis Example 3: Synthesis of Compound 3

The reaction and purification were carried out in the same manner as in the synthesis of the compound 1 except that 8.4 g (20.43 mmol) of Intermediate 1-2 and 5.12 g (22.47 mmol) of dibenzo [b, d] thiophen-4-ylboronic acid were used and 62% To give compound 3.

Synthesis Example 4: Synthesis of Compound 4

1) Synthesis of intermediate 4-1

4 mol% of Bis (dibenzylideneacetone) palladium (pd (dba) ₂ ), 0.27 g of Tricyclohexylphosphine, 12.5 g of bis (pinacolato) diboron, 14.59 mmol of potassium acetate, 2.39 g (0.97 mmol) were dissolved in 50 mL of dioxane and stirred at 100 占 폚 for 12 hours. After the reaction is completed, cool to room temperature, add anhydrous magnesium sulfate, stir, filter with a silica pad, and concentrate under reduced pressure. Column purification afforded Intermediate 4-1 in 85% yield.

2) Synthesis of Compound 4

The reaction and purification were carried out in the same manner as in the synthesis of the compound 1 except that 4.75 g (10.34 mmol) of Intermediate 4-1 and 4.25 g (10.3 mmol) of Intermediate 1-2 were used, and Compound 4 was obtained in a yield of 70%.

Synthesis Example 5: Synthesis of Compound 5

1) Synthesis of intermediate 5-1

Intermediate 1-1 was obtained in the same manner as in Intermediate 1 except that 5 g (13.45 mmol) of Intermediate 1-1 and 4.47 g (13.45 mmol, Cas No. 1247053-55-9) of 5-phenyl-5,12-dihydroindolo [ 2 and purified to obtain Intermediate 5-1 in 51% yield.

2) Synthesis of Compound 5

The reaction and purification were carried out in the same manner as in the synthesis of the compound 1 except that 4 g (6.9 4 mmol) of Intermediate 5-1 and 1.62 g (7.63 mmol) of dibenzo [b, d] furan- ≪ / RTI >

Synthesis Example 6: Synthesis of Compound 6

The reaction and purification were carried out in the same manner as in the synthesis of the compound 1 except that 4 g (6.94 mmol) of Intermediate 5-1 and 1.62 g (7.63 mmol) of dibenzo [b, d] furan- ≪ / RTI >

Synthesis Example 7: Synthesis of Compound 7

1) Synthesis of intermediate 7-1

Synthesis of Intermediate 1-2, except that 5 g (13.45 mmol) of Intermediate 1-1 and 5.14 g (13.45 mmol) of 5- (naphthalen-2-yl) -5,12- dihydroindolo [3,2- , And purified to give Intermediate 6-1 in 57% yield.

2) Synthesis of Compound 7

The reaction and purification were carried out in the same manner as in the synthesis of the compound 1 except that 4.8 g (7.67 mmol) of Intermediate 7-1 and 1.92 g (8.44 mmol) of dibenzo [b, d] thiophen- % Yield.

Synthesis Example 8: Synthesis of Compound 8

1) Synthesis of Intermediate 8-1

dibenzo [b, d] furan-2-ylboronic acid and 9.48 g (47.16 mmol) of 1-bromo-2-nitrobenzene were used in the same manner as in the synthesis of Compound 1, except that Intermediate 8 -1 < / RTI > in 78% yield.

2) Synthesis of intermediate 8-2

10.6 g (36.78 mmol) of Intermediate 8-1 and 90 mL of triethyl phosphite were placed and stirred under reflux. The mixture was stirred for 10 hours, cooled to room temperature, and concentrated under reduced pressure. After washing with water, extract with ethylacetate, extract only the organic layer, add anhydrous magnesium sulfate, stir, filter with a silica pad, and concentrate under reduced pressure. Column purification gave Intermediate 8-2 in 66% yield.

3) Synthesis of intermediate 8-3

The reaction and purification were carried out in the same manner as in the synthesis of Intermediate 1-2, except that 6.24 g (24.27 mmol) of Intermediate 8-2 and 9.02 g (24.27 mmol) of Intermediate 1-1 were used, and Intermediate 8-3 was obtained in 55% Respectively.

4) Synthesis of Compound 8

The reaction and purification were carried out in the same manner as in the synthesis of the compound 1 except that 6.69 g (13.35 mmol) of Intermediate 8-3 and 3.12 g (14.69 mmol) of dibenzo [b, d] furan- % Yield.

Experimental Example 1: Evaluation of physical properties of oil-soluble compounds

The physical properties of the compounds 1 to 4 synthesized in Synthesis Examples 1 to 4 were simulated. The highest level occupied molecular orbital (HOMO) energy level, lowest level boiling point molecular orbital (LUMO) energy level, glass transition temperature (T _g ), melting point (T _m ), decomposition temperature (Td) The evaporation temperature, the triplet energy level (T ₁ ), and the difference between the triplet energy level and the single energy level (ΔE _ST ) were evaluated. The evaluation results are shown in Table 1 below. The physical properties of the organic compounds used in Comparative Examples to be described later were evaluated together with Comparative Examples (Ref.).

Properties of organic compounds compound HOMO
(eV) LUMO
(eV) PL-λ _max
(nm) T _g
(° C) T _m
(° C) T _d-1 %
(° C) Evap.
(° C) T ₁
(eV) Comparative Example -5.90 -2.28 350 98 270 332 Melt, 290 2.89 Compound 1 -6.01 -2.58 376 138 324 397 Melt, 340 2.91 Compound 2 -6.12 -3.13 432 145 318 460 Melt, 400 2.85 Compound 3 -6.22 -3.07 419 158 310 377 Melt, 320 2.80 Compound 4 -5.87 -2.43 362 144 291 398 Melt, 330 2.73 HOMO: Film (100 nm / ITO), by AC3, LUMO: produced at film adsorption edge;
T1 gap: value calculated by Gaussian ED-DFT (time-dependent density functional theory).
Eg: LUMO - HOMO; T _g , T _m : measured with TA Q100; T _d : measured with TA Q500

As shown in Table 1, the HOMO energy level, the LUMO energy level, and the energy band gap of the compounds 1 to 4 were suitable for use in the light emitting material layer, and in consideration of the triplet energy level, Was suitable for energy transfer for forming an exciton, and it was confirmed that good luminescence efficiency was obtained while reducing non-emission disappearance. Also, it was confirmed that the glass transition temperature, melting point, and evaporation temperature were high, and the heat resistance was also excellent.

Example 1: Fabrication of organic light emitting diode using Compound 1

An organic light emitting diode was prepared by applying Compound 1 as a host of a light emitting material layer. First, the glass substrate with 40 mm x 40 mm x 0.5 mm thick ITO (with reflector) electrodes was ultrasonically cleaned with isopropyl alcohol, acetone, DI water for 5 minutes, and then dried in an oven at 100 ° C. After the substrate was cleaned, it was subjected to an O ₂ plasma treatment in a vacuum for 2 minutes and transferred to a deposition chamber for deposition of other layers on the top. An organic layer was deposited by evaporation from a heated boat under a vacuum of about 10 ^-7 Torr in the following order. At this time, the deposition rate of the organic material was set to 1 Å / s.

A hole injection layer (HIL; HAT-CN, 70 ANGSTROM), a hole transport layer (HTL; NPB, 780 ANGSTROM), an electron blocking layer (EBL; mCBP, 150 ANGSTROM) A retardation fluorescent material of 4CzIPN of 30 wt% doping, 350 ANGSTROM), a hole blocking layer (HBL; B3PYMPM; 100 ANGSTROM), an electron transport layer (ETL: TPBi, 250 ANGSTROM), an electron injection layer (EIL; LiF, 8 ANGSTROM) Cathode (Al; 1000 A).

A capping layer (CPL) was formed and encapsulated with glass. After deposition of these layers, the film was transferred from the deposition chamber into a dry box for subsequent film formation and subsequently encapsulated using a UV cured epoxy and a getter.

Examples 2 to 4: Fabrication of organic light emitting diodes

Compound 2 (Example 2) synthesized in Synthesis Example 2, Compound 3 (Example 3) synthesized in Synthesis Example 3, Compound 4 (Synthesis Example 4) synthesized in Synthesis Example 4 (Example 4) ) Was used as the organic light emitting diode, and the procedure of Example 1 was repeated to produce an organic light emitting diode.

Comparative Example: Fabrication of organic light emitting diode

The procedure of Example 1 was repeated except that the following compounds were used instead of Compound 1 as the host of the luminescent material layer to prepare an organic light emitting diode.

[Comparative Example Host]

Experimental Example: Measurement of luminescence characteristics of organic light emitting diode

The properties of the organic light emitting diodes fabricated in Examples 1 to 4 and Comparative Examples were measured. 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). (Cd / A), power efficiency (lm / W), external quantum efficiency (EQE), CIE chromaticity coordinates, and 3000 (nm) of the organic light emitting diodes at a current density of 10 mA / The time from the nit to the time when the brightness was reduced to 95% (T ₉₅ ) was measured. The measurement results are shown in Table 2 below.

Properties of Organic Light Emitting Diodes device V cd / A lm / W EQE (%) CIE (x) CIE (y) T ₉₅ Comparative Example 4.82 45.5 29.7 15.4 0.342 0.597 200 Example 1 4.22 48.7 36.2 16.6 0.348 0.596 280 Example 2 4.42 52.1 37.0 17.5 0.352 0.593 332 Example 3 4.41 46.4 33.1 15.7 0.368 0.587 318 Example 4 3.90 47.2 38.3 16.0 0.343 0.597 320

As shown in Table 2, when the organic compound synthesized according to the present invention was used as a host of the light emitting material layer, the driving voltage was reduced by a maximum of 23.6% as compared with the case where the material of the comparative example was used as the host of the light emitting material layer, Current efficiency, power efficiency, external quantum efficiency and device lifetime (T ₉₅ ) were increased by up to 14.5%, 28.6%, 13.6% and 66%, respectively. As a result, it has been confirmed that the organic compound of the present invention is applied to the organic light emitting layer to lower the driving voltage of the light emitting diode, improve the light emitting efficiency, and improve the device lifetime. Accordingly, the organic light emitting diode according to the present invention can be utilized for an organic light emitting diode display device and / or a light emitting device such as an illumination device, which has low power consumption and improved luminous efficiency and device life.

Although the present invention has been described based on the exemplary embodiments and examples of the present invention, the scope of the present invention is not limited to the technical ideas described in the embodiments and examples. It will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope of the present invention. It is evident, however, that the appended claims are intended to cover all such modifications and changes as fall within the scope of the invention.

100, 200, 400: organic light emitting diode
110, 210, 410: first electrode 120, 220, 420: second electrode
130, 230, 430: an organic light emitting layer 140, 240: a 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 Td: driving thin film transistor

Claims (12)

An organic compound represented by the following formula (1).
Formula 1

Wherein R ₁ to R ₁₅ are each independently selected from the group consisting of hydrogen, deuterium, tritium, silyl groups, C ₁ to C ₂₀ alkyl groups, C ₁ to C ₂₀ alkoxy groups, C ₁ to C ₂₀ alkylamine groups, C ₅ ~ C ₃₀ Homo aryl group, C ₄ ~ C ₃₀ heteroaryl group, C ₅ ~ C ₃₀ Homo alkylaryl group, C ₄ ~ C ₃₀ heteroaryl-alkyl aryl group, C ₅ ~ C ₃₀ Homo aryloxy group, C ₄ ~ C ₃₀ heteroaryloxy group, C ₅ ~ C ₃₀ Homo arylamine group, a C ₄ ~ C ₃₀ heteroaryl amine group, or adjacent groups unsubstituted or combined substituted each other C ₅ ~ C _30-homo-aryl group or a C ₄ ~ C ₃₀ heteroaryl group X and Y are each independently oxygen (O) or sulfur (S)
The method according to claim 1,
Wherein the organic compound represented by the formula (1) is a compound represented by the following formula (2a) or (2b).
Formula 2a

2b

(In the formulas (2a) and (2b), R ₁ to R ₁₅ , X and Y are each the same as defined in formula (1)
The method according to claim 1,
Wherein the organic compound represented by the formula (1) is any compound represented by the following formula (3).
(3)

A first electrode and a second electrode facing each other; And
And an organic light emitting layer disposed between the first electrode and the second electrode,
Wherein the organic light emitting layer comprises an organic compound represented by Formula 1 below.
Formula 1

Wherein R ₁ to R ₁₅ are each independently selected from the group consisting of hydrogen, deuterium, tritium, silyl groups, C ₁ to C ₂₀ alkyl groups, C ₁ to C ₂₀ alkoxy groups, C ₁ to C ₂₀ alkylamine groups, C ₅ ~ C ₃₀ Homo aryl group, C ₄ ~ C ₃₀ heteroaryl group, C ₅ ~ C ₃₀ Homo alkylaryl group, C ₄ ~ C ₃₀ heteroaryl-alkyl aryl group, C ₅ ~ C ₃₀ Homo aryloxy group, C ₄ ~ C ₃₀ heteroaryloxy group, C ₅ ~ C ₃₀ Homo arylamine group, a C ₄ ~ C ₃₀ heteroaryl amine group, or adjacent groups unsubstituted or combined substituted each other C ₅ ~ C _30-homo-aryl group or a C ₄ ~ C ₃₀ heteroaryl group X and Y are each independently oxygen (O) or sulfur (S)
5. The method of claim 4,
Wherein the organic compound is a compound represented by the following formula (2a) or (2b).
Formula 2a

2b

(In the formulas (2a) and (2b), R ₁ to R ₁₅ , X and Y are each the same as defined in formula (1)
5. The method of claim 4,
Wherein the organic compound represented by Formula 1 is any compound represented by Formula 3 below.
(3)

5. The method of claim 4,
Wherein the organic compound is used as a host of the light emitting material layer.
8. The method of claim 7,
Wherein the light emitting material layer further comprises a dopant.
9. The method of claim 8,
(HOMO ^H -HOMO ^D |) between the highest level occupied molecular orbital energy level (HOMO ^H ) of the host and the highest level occupied molecular orbital energy level (HOMO ^D ) of the dopant or the lowest level non occupied molecular orbital Wherein the difference (LUMO ^H -LUMO ^D ) between the energy level (LUMO ^H ) and the lowest level non occupied molecular orbital energy level (LUMO ^D ) of the dopant is 0.5 eV or less.
9. The method of claim 8,
Excited state singlet energy level (S ₁ ^D) and the organic light emitting diode difference (ΔE _ST ^D) is 0.3 eV or less of the excited state triplet energy level (T ₁ ^D) of the dopant.
Board;
The organic light emitting diode according to any one of claims 4 to 10, which is disposed on the substrate; And
And a driving unit connected to the first electrode of the organic light emitting diode,
And an organic light emitting device.
12. The method of claim 11,
Wherein the organic light emitting device includes an organic light emitting diode display.

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