KR20180047313A - Organic compound and light emitting diode and organic light emitting diode display device using the same - Google Patents

Abstract

The present invention relates to an organic compound in which a nitrogen atom substituted with at least one condensed aromatic ring to an imidazo benzothiazole core. The organic compound of the present invention comprises: an imidazo benzothiazole core having a wide band gap; and an amine group substituted with a condensed aromatic ring excellent in thermal stability, and having superior hole transfer properties and/or electron blocking properties. When the organic compound of the present invention is applied to a hole layer, an electron blocking layer, and/or a charge generation layer of a light emitting diode, the light emitting diode can be driven at a low voltage by exhibiting excellent hole transfer properties. Since a sufficient current density can be secured even at a low voltage, the stress on a compound constituting a light emitting element by high voltage driving is reduced. Therefore, it is possible to greatly improve the light emitting efficiency of the light emitting diode to which the organic compound of the present invention is applied, and to improve the lifetime of the light emitting element.

Description

TECHNICAL FIELD [0001] The present invention relates to an organic compound, a light emitting diode using the same, and an organic light emitting diode (OLED)

The present invention relates to an organic compound used in an organic light emitting diode, and more particularly, to an organic compound which has an excellent hole transporting property and / or an electron blocking property to lower a driving voltage of a light emitting diode and improve a light emitting efficiency, And an organic light emitting diode (OLED) display.

2. Description of the Related Art Recently, as the size of a display device has been increased, there has been an increasing demand for a flat display device having less space occupancy. One of such flat display devices is an organic light emitting diode (OLED) display device including a light emitting diode and also referred to as an organic electroluminescent device Devices (organic light emitting diode (OLED) display devices) are rapidly evolving.

When a charge is injected into an organic light emitting layer formed between an electron injection electrode (cathode) and a hole injection electrode (anode), the light emitting diode is a device that emits light while paired with electrons. The device can be formed on a flexible transparent substrate such as a plastic substrate. Further, the device can be driven at a low voltage (10 V or less), has relatively low power consumption, and has excellent color purity.

In a light emitting diode used in an organic light emitting diode display, electrons and holes are paired when charges are injected into an organic light emitting layer formed between an electron injection electrode (cathode) and a hole injection electrode (anode) It is a device that extinguishes light. In the organic light emitting layer, electrons and holes meet to form an exciton, and the organic compound contained in the organic light emitting layer becomes an excited state due to the energy. When the organic compound is excited in an excited state to a ground state Transition occurs, and the generated energy is emitted to emit light.

The organic light emitting layer may have a single layer structure of the light emitting material layer or may have a multi-layer structure for improving the light emitting efficiency. For example, the organic light emitting layer may include a hole injection layer (HIL), a hole transporting layer (HTL), an emitting material layer (EML), an electron transporting layer (ETL) Layer structure composed of an electron injection layer (EIL).

On the other hand, a light emitting diode having a tandem structure, which is manufactured by stacking a plurality of unit elements so that the performance of the light emitting diode is further improved and a white light emitting diode can be realized, has been proposed. The light emitting diode of such a tandem structure includes a charge generation layer (CGL) disposed between each unit element for supplying a positive charge and a negative charge to each unit element, respectively.

The organic material used for the organic light emitting diode including the organic light emitting diode including the tandem structure can be largely divided into the light emitting material and the charge transport material. The charge transport material includes a hole injection material, a hole transport material, an electron transport material, Material, and the like. In organic light emitting diodes, high driving voltage and current density adversely affect the stability of the material and the lifetime of the device because of the strong stress applied to the material constituting the device.

Therefore, researches for increasing the efficiency of the light emitting diode and lowering the power consumption by adjusting the energy levels of the hole transporting layer and the hole injecting layer constituting the organic light emitting diode have progressed. Korean Patent Laid-Open Publication No. 2015-0026463, for example, discloses that a charge transfer material having a vinyl terminal group can be applied to an organic layer to suppress deterioration of an organic layer and prevent pixel shrinkage, thereby improving lifetime of the device.

However, by improving the current density of the light emitting device, reducing the driving voltage, and lowering the stress on the material constituting the light emitting device, it is possible to improve the lifetime of the light emitting device, Development of improved materials is still required.

An object of the present invention is to provide an organic compound having excellent hole transporting ability and / or electron blocking ability and having a wide band gap and excellent thermal stability.

It is another object of the present invention to provide a light emitting diode and an organic light emitting diode device having less stress to a material constituting the light emitting device, improving the lifetime of the light emitting device, and improving the light emitting efficiency.

According to an aspect of the present invention, there is provided a method for producing an imidazobenzothiazole core having a wide bandgap, which comprises directly or indirectly linking an amine group substituted with at least one condensed aromatic ring Organic compounds.

Since the organic compound according to the present invention has excellent hole transporting property and electron blocking property and is excellent in thermal stability, the organic compound according to the present invention can realize low-voltage driving when applied to a light emitting device, The lifetime of the device can be improved and the luminous efficiency can be improved.

According to another aspect of the present invention, there is provided an organic electroluminescent device, wherein an organic compound in which an amine group substituted with at least one condensed aromatic ring is directly or indirectly connected to an imidazobenzothiazole core is used as an organic light emitting layer, And / or a charge generation layer, and an organic light emitting diode display device including the light emitting diode as a light emitting element.

The present invention proposes an organic compound in which an imidazobenzothiazole core is directly or indirectly linked with a nitrogen atom substituted by at least one condensed aromatic ring. A nitrogen atom is substituted by an imidazobenzothiazole core capable of securing a wide band gap and at least one condensed aromatic ring having a nitrogen atom which is excellent in hole transporting property and charge generating property and is excellent in thermal stability.

Therefore, the organic compound of the present invention can be applied as a host of an organic layer in which a hole transport, a hole injection characteristic, a charge generation characteristic and / or an electron blocking characteristic is required in a light emitting diode.

The light emitting diode and the organic light emitting diode display device including the positive hole layer and / or the electron blocking layer made of the organic compound of the present invention have good current density and can be driven at a low voltage, so that power consumption is reduced. Voltage driving is enabled, stress on the material constituting the light emitting device is reduced, lifetime of the device can be improved, and luminous efficiency is improved due to good hole mobility.

Further, the light-emitting diode and the organic light-emitting diode display device having the tandem structure including the charge generation layer and / or the electron blocking layer made of the organic compound of the present invention can reduce the power consumption, improve the lifetime of the device, And a high purity white color can be realized.

1 is a cross-sectional view schematically showing a light emitting diode having a single-layer structure to which an organic compound according to the first exemplary embodiment of the present invention can be applied.
2 is a cross-sectional view schematically showing a light emitting diode having a single-layer structure to which an organic compound according to a second exemplary embodiment of the present invention can be applied.
3 is a cross-sectional view schematically showing a light emitting diode having a tandem structure to which an organic compound according to a third exemplary embodiment of the present invention can be applied.
4 is a cross-sectional view schematically showing a light emitting diode having a tandem structure to which an organic compound according to a fourth exemplary embodiment of the present invention can be applied.
5 is a schematic cross-sectional view of a light emitting diode having a tandem structure to which an organic compound according to the fifth exemplary embodiment of the present invention can be applied.
6 is a schematic cross-sectional view of an organic light emitting diode display including a light emitting diode to which an organic compound according to an exemplary embodiment of the present invention can be applied.
FIGS. 7 to 14 are graphs showing NMR analysis results for organic compounds synthesized according to the exemplary embodiments of the present invention, respectively.
15A to 15C are graphs showing the results of measuring current density, luminance, and current efficiency of a light emitting diode including a single light emitting unit in which an organic compound according to an exemplary embodiment of the present invention is applied to an exciton blocking layer.
16A and 16B are graphs showing current density and luminance of a light emitting device having a tandem structure composed of two light emitting units, in which an organic compound according to an exemplary embodiment of the present invention is applied to an upper exciton blocking layer Fig.

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

[Organic compounds]

The present invention directly or indirectly links nitrogen atoms substituted with at least one condensed aromatic ring to an imidzozo benzothiazole core capable of ensuring a wide band gap. For example, the core of the organic compound according to the present invention may have an imidazo [2,1-b] benzothiazole core and may be represented by the following formula (1).

[Chemical Formula 1]

(Wherein R ₁ to R ₄ are each independently an unsubstituted or substituted C 1 to C 20 alkyl group, an unsubstituted or substituted C 1 to C 20 alkoxy group, an unsubstituted or substituted C 5 to C 30 aryl group, an unsubstituted or substituted An unsubstituted or substituted C5 to C30 heteroaryl group, an unsubstituted or substituted C5 to C30 arylalkyl group, an unsubstituted or substituted C4 to C30 heteroarylalkyl group, an unsubstituted or substituted C5 to C30 aryloxyl group, and an unsubstituted or substituted C4 to C30 At least one of R ₁ to R ₄ is a C5 to C30 aryl group or a C4 to C30 heteroaryl group having a fused aromatic ring, and L ₁ to L ₆ are each independently selected from the group consisting of A, b, c, d, e, and f are each independently 0 or 1, provided that at least one of them is 1, m and n are each independently a C5 to C30 arylene group or a C4 to C30 heteroarylene group, Independently 0 or 1, and m + n is 1)

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 may be, for example, a C1-C20 alkyl group which is unsubstituted or substituted by halogen, a C1-C20 alkoxy group which is unsubstituted or substituted by halogen, a halogen, cyano group, A C5 to C30 aryl substituted amine group, a C4 to C30 heteroaryl substituted amine group, a nitro group, a hydrazyl group, a sulfonic acid group, a C1 to C20 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 heteroarylsilyl group, a C 5 to C 30 aryl group and a C 4 to C 30 heteroaryl group. But is not limited thereto.

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.

In one exemplary embodiment, each of R ₁ to R ₄ independently represents an unsubstituted or substituted phenyl, biphenyl, terphenyl, naphthyl, anthracenyl, pentanenyl, indenyl, A phenanthrenyl group, a dibenzophenanthrenyl group, an azulenyl group, a pyrenyl group, a fluoranthienyl group, a triphenylenyl group, a cyano group, a phenanthrenyl group, a phenanthrenyl group, (Such as a fused or condensed group such as a phenyl group, a phenanthryl group, a phenanthryl group, a phenanthryl group, a phenanthryl group, a phenanthryl group, a phenanthryl group, a phenanthryl group, Or a heterocyclic group which may be substituted with at least one substituent selected from the group consisting of a halogen atom, a cyano group, a cyano group, , Indazole diazonium, indole A heterocyclic group, a thiazolyl group, a thiazolyl group, a thiomorpholinyl group, a thiomorpholinyl group, a thiazolyl group, a thiazolyl group, a thiazolyl group, A benzoquinazolinyl group, a benzoquinazolinyl group, a benzoquinolinyl group, a benzoquinazolinyl group, a benzoquinazolinyl group, a benzoquinazolinyl group, a benzoquinazolinyl group, a benzoquinazolinyl group, a benzoquinazolinyl group, a benzoquinazolinyl group, a benzoquinazolinyl group, a benzoquinazolinyl group, a quinolizinyl group, A thienyl group, a naphthyridinyl group, a furanyl group, a paranyl group, an oxazinyl group, an oxazolyl group, an oxadiazole group, an oxazolyl group, an oxazolyl group, A thiazolyl group, a thiophenyl group, a benzothiophenyl group, a diethoxyphenyl group, a thiopyranyl group, a thiopyranyl group, a dithienyl group, a chlorenyl group, A benzothiophenyl group, a difluoropyrazinyl group, or an N-substituted spiro And at least one of R ₁ to R ₄ is a homoaryl group or a heteroaryl group having a condensed ring.

The condensed rings which may constitute R ₁ to R ₄ may contain two or more, preferably three or more aromatic rings. For example, the condensed ring may be a substituted or unsubstituted naphthyl, anthracenyl, pentanenyl, indenyl, indenoindenyl, hepttalenyl, biphenylenyl, indacenyl, phenalenyl, A phenanthrenyl group, a benzenephenanthrenyl group, a dibenzophenanthrenyl group, an azulenyl group, a pyrenyl group, a fluoranthenyl group, a triphenylrenyl group, a pyrenyl group, a klychenyl group, a tetraphenyl group, a tetracenyl group, , Condensed homoaromatic rings such as a pyrenyl group, a pentaphenyl group, a pentacenyl group, a fluorenyl group, an indenofluorenyl group, or a spirosporo fluorenyl group and / or an indolyl group, an isoindolyl group, an indazolyl group , An indolizinyl group, a pyrrolidinyl group, a carbazolyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an indolocarbazolyl group, an indenocarbazolyl group, a quinolinyl group, an isoquinolinyl group, A quinoxalinyl group, a cyano group, A quinolinyl 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, A phenanthrolinyl group, a peranthrylinyl group, a perimidinyl group, a phenanthridinyl group, a phthalidinyl group, a cinnolinyl group, a naphthyridinyl group, a dioxinyl group, a benzofuranyl group, a dibenzofuranyl group, a thiopyranyl group, , An isochromenyl group, a benzothiophenyl group, a dibenzothiophenyl group, a difluoropyrazinyl group, or a condensed heteroaromatic ring such as an N-substituted spiropyranyl group.

On the other hand, in one non-limiting embodiment, L ₁ to L _{6, which} are linkers in the formula (1), may be aromatic linking groups.

Specifically, in formula (1), L ₁ to L ₆ each independently represent a substituted or unsubstituted phenylene, biphenylene, terphenylene, tetraphenylene, indenylene, naphthylene, azulenylene, indacenylene, acenaphthylene, fluorenylene, spiro-fluorenylenylene, naphthylene, naphthylene, azulenylene, indenylene, A phenanthrenylene group, a phenanthrenylene group, an anthracenylene group, a fluororanthrenylene group, a triphenylenylene group, a pyrenylene group, a chlorenylene group, a phenanthrene group, a phenanthrene group, naphthacene, naphthacenylene, picenylene, perylenylene, pentaphenylene, hexacenylene, pyrrolylene, imidazolylene, and the like. (imidazolylene), p And examples thereof include pyrazolylene, pyridinylene, pyrazinylene, pyrimidinylene, pyridazinylene, isoindolylene, indolylene, and the like. Indazolylene, purinylene, quinolinylene, isoquinolinylene, benzoquinolinylene, phthalazinylene, naphthylene, and the like. A naphthyridinylene group, a quinoxalinylene group, a quinazolinylene group, a benzoquinolinylene group, a benzoisoquinolinylene group, a benzoquinazolinylene group, a benzoquinoxalinylene group, And examples thereof include cinnolinylene, phenanthridinylene, acridinylene, phenanthrolinylene, phenazinylene, benzoxazolylene, benzimidazolylene, (benzimidazolylene) , Furanylene, benzofuranylene, thiophenylene, benzothiophenylene, thiazolylene, isothiazolylene, benzothiazolylene, benzothiophenylene, benzothiophenylene, benzoxazolinone, benzothiazolylene, isoxazolylene, oxazolylene, triazolylene, tetrazolylene, oxadiazolylene, triazinylene, dibenzofuranylene, , Dibenzothiophenylene group, carbazolylene group, benzocarbazolylene group, dibenzocarbazolylene group, indolocarbazolylene group, indenocarbazolylene group, imidazopyrimidinylene group, imidazopyrimidinylene group, imidazopyrimidinylene group, And imidazopyridinylene. ≪ / RTI >

At this time, if the number of aromatic rings constituting L ₁ to L ₆ is increased, the conjugated structure of the entire organic compound becomes excessively long, so that the bandgap of the organic compound can be reduced. Therefore, the number of aromatic rings constituting L ₁ to L ₆ is preferably 1 to 2, more preferably 1. Also, with respect to the injection and transport properties of holes, L ₁ to L ₆ may each be a 5-membered ring to a 7-membered ring, -membered ring. For example, L ₁ to L ₆ are independently selected from the group consisting of substituted or unsubstituted phenylene, biphenylene, pyrrolylene, imidazolylene, pyrazolylene, pyridinylene, A thiophenylene group, a thienylene group, a thienylene group, a thienylene group, a thienylene group,

The organic compound represented by the general formula (1) has an aminobenzothiazole core having a wide band gap connected with an amine group containing a nitrogen atom linked by at least one condensed ring. Accordingly, the organic compound represented by Formula (1) has excellent hole transporting properties, excellent luminous efficiency and color purity, and excellent thermal stability. When the organic compound represented by the general formula (1) is applied to the organic material layer of the light emitting device, since the hole transporting property is improved in the light emitting device, the driving voltage of the device can be prevented from rising due to injection delay of holes, Can be driven. When the organic compound represented by the general formula (1) is applied to the organic material layer constituting the light emitting device, holes and electrons can be injected in a balanced manner from the organic material layer constituting the light emitting device, thereby increasing the luminous efficiency of the device.

Thus, the organic compound represented by Formula (1) has an imidazobenzothiazole moiety having an excellent hole transporting property and a wide band gap to an amine group substituted with a functional group having excellent thermal stability. Therefore, when the organic compound according to the present invention is applied to the positive hole layer and / or the electron blocking layer of the light emitting device, hole injection into the light emitting material layer and hole transporting property can be improved and conversely, electrons can be prevented from moving to the anode .

In addition, since the organic compound of the present invention has a very high hole transporting ability, a compound having a deepest lowest occupying molecular orbital (deep LUMO) in the organic compound of the present invention adjacent to the organic compound layer containing the organic compound of the present invention In the case of doping a hole injecting material and using it as a charge generating layer, electrons are moved in the opposite direction (for example, the anode direction) of the organic compound layer made of the organic compound of the present invention, The charge generation characteristic is obtained. Therefore, the organic compound represented by the formula (1) may be used alone in an organic layer of a light emitting device, for example, a hole layer such as a hole transporting layer and / or a hole injecting layer, an electron blocking layer and / or a P type charge generating layer, Can be used.

In one exemplary embodiment, the organic compounds of the present invention may have a structure in which at least one condensed aromatic ring is substituted for the nitrogen atom that may be directly or indirectly linked to the imidazolobenzothiazole core, Can be represented by the following formula (2).

(2)

Wherein R ₅ and R ₇ are each independently an unsubstituted or substituted C 5 to C 30 aryl group, an unsubstituted or substituted C 4 to C 30 heteroaryl group, an unsubstituted or substituted C 5 to C 30 arylalkyl group, substituted C4 ~ C30 heteroaryl group, an unsubstituted or substituted C5 ~ C30 aryloxy group and an unsubstituted or substituted and selected from the group consisting of substituted C4 ~ C30 heteroaryloxy group, R ₆ and R ₈ are each independently condensed (fused) C5 ~ C30 aryl group or C4 ~ C30 heteroaryl having a ring aryl group, and, L ₁ to _{L 6, a, b, c} , d, e, f, m, n are each as defined in formula (I) Lt; / RTI >

The organic compound represented by the general formula (2) is bonded to an imidazobenzothiazole core having a wide band gap with an amine group containing a nitrogen atom substituted with at least one condensed aromatic ring having excellent thermal stability. The organic compound represented by the general formula (2) has excellent hole transporting properties, good thermal stability and excellent color purity. When the organic compound represented by the general formula (2) is applied to a light emitting device, hole injection into the organic material layer, for example, the light emitting material layer, and hole transporting ability are improved, and the driving voltage of the light emitting device is reduced to reduce power consumption. Further, the stress of the material constituting the light emitting element can be reduced, and the lifetime and luminous efficiency of the element can be improved.

[Light Emitting Diodes and Display Devices]

The organic compounds represented by the general formulas (1) to (2) are excellent in hole transporting properties and can therefore be applied to organic layers such as a hole layer, an electron blocking layer and / or a charge generating layer of a light emitting device. A light emitting diode to which an organic compound according to the present invention is applied to an organic material layer will be described first. 1 is a schematic cross-sectional view of a light emitting diode according to a first exemplary embodiment of the present invention.

1, a light emitting diode 100 according to a first exemplary 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 120, 110, and 120, respectively. The light emitting unit 130 includes a hole layer 140 composed of a hole injection layer (HIL) 150 and a hole transporting layer (HTL) 160, a light emitting material layer (EML) 170 , An electron transporting layer (ETL) 180, and an electron injection layer (EIL) 190.

The first electrode 110 is made of a conductive material having a relatively large work function and is an anode. For example, the first electrode 110 may be formed of indium-tin-oxide (ITO) or indium-zinc-oxide (IZO).

The second electrode 120 is made of a conductive material having a relatively small work function value and is a cathode. For example, the second electrode 120 may be made of aluminum (Al), magnesium (Mg), calcium (Ca), silver (Ag), or an alloy thereof.

The light emitting material layer 170 constituting the light emitting unit 130 may be formed by doping a host with a dopant. For example, when the luminescent material layer 170 emits blue (B) light, the luminescent material layer 170 is formed of a group consisting of an anthracene derivative, a pyrene derivative, and a perylene derivative The selected at least one fluorescent host material may be doped with a fluorescent dopant.

For example, the fluorescent host material used for the blue luminescent material layer is 4,4'-bis (2,2'-diphenylvinyl) -1,1'-biphenyl (4,4'-bis (2-naphthyl) anthracene (ADN), 2, 5, 8-diphenylylnyl) -1,1'-biphenyl; DPVBi, 9,10-di- Tert-butyl-9,10-di (2-naphthyl) anthracene, tetra-t-butylperylene (TBADN) (2-naphthyl) anthracene, 2-methyl-9,10-di (2-naphthyl) anthracene, 2 '- (1,3,5-benzenetriyl) -tris (1-phenyl-1-H-benzimidazole) tris (1-phenyl-1-H-benzimidazole; TBPi).

Further, as a blue fluorescent dopant material, 4,4'-bis (9-ethyl-3-carbazovinylene) - 1,1'- (1, 1, 4,1] tetraphenyl-4-yl-vinyl) -phenyl] -amine (diphenyl- [4- (2- [1,1; 4,1] terphenyl-4-yl-vinyl) -phenyl] -amine; BD-1).

In addition, when the light emitting material layer 170 emits green light, the light emitting material layer 170 may include a phosphorescent dopant composed of a metal complex compound (for example, dp ₂ the _{Ir (acac), op 2 Ir} (acac) , and so on) may be formed of doped. In addition, when the light emitting material layer 170 emits red light, the light emitting material layer 170 may include a phosphorescent dopant (for example, Btp ₂ Ir (acac) or the like) may be doped. The dopant material may be added in a proportion of approximately 1 to 30 weight percent based on the host material.

The electron transport layer 180 is located between the light emitting material layer 170 and the second electrode 120 and the electron injection layer 190 is located between the electron transport layer 180 and the second electrode 120. The electron transporting layer 180 may be a derivative such as oxadiazole, triazole, phenanthroline, benzoxazole, benzothiazole, benzimidazole, triazine, etc. have. For example, the electron transport layer 180 may be formed of tris (8-hydroxyquinoline aluminum; Alq ₃ ), 2-biphenyl- Phenyl) -1,3,4-oxadiazole (PBD), spiro-PBD, lithium quinolate (2- [4- (9,10-di-2-naphthalenyl-2-anthracenyl) phenyl] -1-phenyl-1 H-benzimidazole Phenyl-1-phenyl-1H-benzimidazole, 3- (biphenyl-4-yl) -5- (4-tert- butylphenyl) 4H-1,2,4-triazole (TAZ), 4,7-dihydroxy-4-phenyl- Diphenyl-1,10-phenanthroline (Bphen), tris (phenylquinoxaline) (TPQ) and 1,3,5-tris (N- Such as 1,3,5-tris (N-phenylbenzimidazole-2-yl) benzene (TPBI). is.

If necessary, the electron transporting layer 180 may be formed by doping the aforementioned organic material with a metal such as an alkali metal and / or an alkaline earth metal. The alkali metal or alkaline earth metal may be added in a proportion of approximately 1 to 20% by weight based on the above-described organic compound, but the present invention is not limited thereto. The alkali metal component that can be used as a dopant in the electron transporting layer 180 is an alkali metal and / or magnesium (Mg) such as lithium (Li), sodium (Na), potassium (K) and cesium (Cs) , Barium (Ba), radium (Ra), but are not limited thereto. If necessary, the electron transport layer 180 may be divided into two or more layers, not a single layer structure.

The material of the electron injection layer 190 may be an alkali halide material such as LiF, CsF, NaF, or BaF ₂ and / or an organic compound such as lithium quinolate (Liq), lithium benzoate, sodium stearate ) May be used, but the present invention is not limited thereto.

A hole layer 140 is disposed between the first electrode 110 and the light emitting material layer 170. The hole layer 140 includes a hole injection layer 150 positioned between the first electrode 110 and the light emitting material layer 170 and a hole injecting layer 150 between the hole injecting layer 150 and the light emitting material 170. [ And a hole transport layer 160 positioned between the layers 170.

The hole injection layer 150 improves the interface characteristics between the first electrode 110, which is an inorganic material, and the hole transport layer 160, which is an organic material. In one exemplary embodiment, the hole injection layer 150 is formed of a mixture of 4,4 ', 4 "-tris (3-methylphenylphenylamino) triphenylamine (4,4' MTDATA), copper phthalocyanine (CuPc), tris (4-carbazoyl-9-yl-phenyl) amine, TCTA), N, N'- N'-diphenyl-N, N'-bis (1-naphthyl) - 1,1'-biphenyl- (NPB), 1,4,5,8,9,11-hexaazatriphenylene hexacarbonitrile (1, 4, 5, 8, 9, HATCN), 1,3,5-tris [4- (diphenylamino) phenyl] benzene, 1,3,5-tris [4- (diphenylamino) (3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT / PSS), 2,3,5,6-tetrafluoro-7,7,8,8-tetracyano 2,3,4-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ), N- (biphenyl- (9-phenyl-9H-carbazol-3-yl) phenyl) -9H-fluorene- 9,9-dimethyl-N- (4- (9-phenyl-9H-carbazol-3-yl) phenyl) -9H-fluoren-2-amine.

In another alternative embodiment, the hole injection layer 150 may be formed by doping the above-described hole injecting material into the organic compounds represented by the general formulas (1) to (2). At this time, the hole injecting material may be doped at about 0.1 to 50 wt%, but the present invention is not limited thereto.

If necessary, the hole injection layer 150 can be divided into two layers. At this time, the first hole injection layer (not shown) positioned on the first electrode 110 side may be made of only the above-described hole injection material, and the first hole injection layer 2 hole injection layer (not shown) may be formed by doping a hole injecting material into the organic compound of Chemical Formulas 1 to 2.

The hole transport layer 160 is located adjacent to the light emitting material layer 170. The hole transport layer 160 may be formed of organic compounds of the formulas (1) to (2), or may be doped with a hole transporting dopant in the organic compounds of the formulas (1) to (2). If the hole transport layer 160 comprises a hole transporting dopant, the hole transporting dopant may be selected from the group consisting of N, N'-diphenyl-N, N'-bis (3-methylphenyl) -1,1'- - diamine (TPD), NPD, 4,4'-bis (N-diphenyl-N, N'- 4,4'-bis (N-carbazolyl) -1,1'-biphenyl (CBP), and the like. The hole transporting dopant may be doped, for example, to about 0.1 to 50 wt%, but the present invention is not limited thereto.

In an alternative embodiment, the hole transport layer 160 may be comprised of two layers. In this case, the first hole transport layer (not shown) positioned adjacent to the hole injection layer 150 is formed of only an organic compound represented by Chemical Formula 1 to Chemical Formula 2, and a second hole The transport layer (not shown) may be formed by doping the above-described hole transporting dopant in the organic compound represented by the general formulas (1) to (2).

In the drawing, the hole layer 140 is divided into a hole injection layer 150 and a hole transport layer 160. However, the hole layer 140 may be formed by injecting a hole injecting dopant such as MTDATA, CuPc, TCTA, NPB (NPD), HATCN, TDAPB, PEDOT / PSS, F4TCNQ and / or N - (9-phenyl-9H-carbazol-3-yl) phenyl) -9H-fluorene- ≪ / RTI > Since the organic compound of the present invention is excellent in the hole transporting ability, the hole layer doped with the hole injecting dopant in the organic compound of the present invention can also serve as the hole injecting layer and the hole transporting layer. In other words, even if only one layer of the hole layer 140 doped with the hole injecting dopant is present between the first electrode 110 and the light emitting material layer 170 in the organic compound of Chemical Formula 1 to Chemical Formula 2, Can be sufficiently obtained. At this time, the hole injecting dopant can be doped for example at about 0.1 to 50 wt%, but the present invention is not limited thereto.

That is, the light emitting diode 100 according to the first exemplary embodiment of the present invention includes first and second electrodes 110 and 120 facing each other, and a first electrode 110 and a second electrode 120 between the first and second electrodes 110 and 120, The light emitting unit 130 includes a hole layer 140 between the first electrode 110 and the light emitting material layer 170 to which the organic compound according to the present invention can be applied.

The organic compound of the present invention has a wide band gap and is excellent in thermal stability and hole transporting ability. Therefore, when the organic compound of the present invention is used alone in the hole layer 140 or in combination with a suitable hole injecting dopant or hole transporting dopant, the light emitting diode 100 can be driven at a low voltage to reduce power consumption, The life of the diode 100 can be improved and the luminous efficiency can be improved.

2 is a schematic cross-sectional view of a light emitting diode according to a second exemplary embodiment of the present invention. 2, a light emitting diode 200 according to a 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 a light emitting unit 230 positioned between the light emitting units 220. The light emitting unit 230 includes a light emitting material layer 270 and a hole layer 240 positioned between the first electrode 210 and the light emitting material layer 270. The light emitting unit 230 includes a hole layer 240, An electron blocking layer (EBL) 266 positioned between the second electrode 220 and the light emitting material layer 270 and an electron injection layer 290 located between the first electrode 220 and the second electrode 220 do. The hole layer 240 includes a hole injection layer 250 and a hole transport layer 260.

As described above, the first electrode 210 is made of a conductive material having a relatively large work function value, and the second electrode 220 is made of a conductive material having a negative work function and a relatively small work function value.

The light emitting material layer 270 may be formed by doping a host with a dopant. The electron transport layer 280 positioned between the light emitting material layer 270 and the second electrode 220 may be formed of a material selected from the group consisting of oxadiazole, triazole, phenanthroline, benzoxazole, Benzothiazole, benzimidazole, triazine, and the like. The electron transport layer 280 may include a dopant such as an alkali metal or an alkaline earth metal.

The electron injection layer 290 located between the electron transport layer 280 and the second electrode 220 may be formed of an alkali halide based material such as LiF, CsF, NaF, BaF ₂ , and / or lithium quinolate (Liq) lithium benzoate, sodium stearate, and the like.

The hole injection layer 250 improves the interface characteristics between the first electrode 210, which is an inorganic material, and the hole transport layer 260, which is an organic material. In one exemplary embodiment, the hole-injecting layer 250 is formed of a material selected from the group consisting of MTDATA, CuPc, TCTA, NPB (NPD), HATCN, TDAPB, PEDOT / PSS, F4TCNQ, N- -9-dimethyl-N- (4- (9-phenyl-9H-carbazol-3-yl) phenyl) -9H- (9-phenyl-9H-carbazol-3-yl) phenyl) -9H-fluoren-2-amine. In an alternative embodiment, the hole injection layer 250 may be formed by doping the organic compound represented by the general formulas (1) to (2) with the hole injection material described above.

In another exemplary embodiment, the hole injecting layer 250 may include a first hole injecting layer (not shown) made of a hole injecting material, a second hole injecting layer (not shown) doped with a hole injecting material, And an injection layer (not shown).

The hole transport layer 260 may be formed of only organic compounds represented by Chemical Formula 1 to Chemical Formula 2 or doped with hole transporting dopants such as TPD, NPD, and / or CBP to organic compounds represented by Chemical Formula 1 to Chemical Formula 2. In an alternative embodiment, the hole transport layer 260 includes a first hole transport layer (not shown) consisting only of an organic compound represented by Chemical Formula 1 to Chemical Formula 2, and an organic compound represented by Chemical Formula 1 to Chemical Formula 2 doped with a hole transporting dopant And a second hole transporting layer (not shown).

On the other hand, when the holes move to the second electrode 220 through the light emitting material layer 270 or when the electrons move to the first electrode 210 through the light emitting material layer 270, Can be imported. In order to prevent this, the light emitting diode 200 according to the second embodiment of the present invention may include an exciton blocking layer in at least one of the upper and lower portions of the light emitting material layer 270.

For example, the electron blocking layer 266 may be located between the first electrode 210 and the light emitting material layer 270, independently of the hole layer 240, to control electron migration. In one exemplary embodiment, the electron blocking layer 266 may be comprised of any one of the organic compounds represented by Formulas (1) to (2).

As described above, since the organic compounds represented by the general formulas (1) to (2) have high hole transporting properties, their electron transporting properties are poor. When the organic compound represented by Chemical Formula 1 to Chemical Formula 2 is applied to the electron blocking layer 266 located between the hole layer 240 and the light emitting material layer 270 independently of the hole layer 240, Electrons transferred from the electrode 220 are bound to the light emitting material layer 270 and can not move toward the first electrode 210. Since electrons are confined to the light emitting material layer 270, electrons and holes can efficiently form excitons in the light emitting material layer 270 to maintain a high light emitting efficiency. A hole blocking layer (HBL) (not shown) as an exciton blocking layer is disposed between the electron transporting layer 280 and the hole transporting layer 280 to prevent movement of holes between the electron transporting layer 270 and the electron transporting layer 280. In one exemplary embodiment, oxadiazole, triazole, phenanthroline, benzoxazole (which may be used in the electron transport layer 280) as the material of the hole blocking layer benzoxazole, benzothiazole, benzimidazole, triazine and the like can be used. (For example, a hole blocking layer (not shown)) has a low occupied molecular orbital (HOMO) level of 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline Bis (2-methyl-8-quinolinolato) (4-phenylphenolato) aluminum (III), 9-dimethyl-4,7-diphenyl-1,10-phenanthroline -methyl-8-quinolinolato (4-phenylphenolato) aluminum (III) BAlq).

The organic compound of the present invention has a wide band gap and is excellent in thermal stability and hole transporting ability. Therefore, when the organic compound of the present invention is used solely for the hole layer 240 and / or the electron blocking layer 266 or in combination with a suitable hole injecting dopant or hole transporting dopant, the light emitting diode 200 is driven at a low voltage Thereby reducing the power consumption, improving the lifetime of the light emitting diode 200 and improving the luminous efficiency.

In addition, the organic compound of the present invention can be applied to light emitting diodes having a tandem structure in addition to light emitting diodes having the above-described single-layer structure to realize low-voltage to white. 3 is a schematic cross-sectional view of a light emitting diode having a tandem structure according to an exemplary third embodiment of the present invention. 3, a light emitting diode 300 according to a third embodiment of the present invention includes a first electrode 310 and a second electrode 320 facing each other, a first electrode 310 and a second electrode 310, A second light emitting unit (upper light emitting unit) 340 positioned between the first light emitting unit 330 and the second electrode 320, and a second light emitting unit And a charge generation layer 350 located between the first and second light emitting units 330 and 340.

As described above, the first electrode 310 is made of a conductive material having a relatively large work function value, and the second electrode 320 is made of a conductive material having a negative work function and a relatively small work function value.

The first light emitting unit 330 includes a hole injection layer 332, a first hole transporting layer 334, a first light emitting material layer 336, a first electron transporting layer 336, A lower electron transporting layer, 338).

The hole injection layer 332 is located between the first electrode 310 and the first luminous material layer 336. In one exemplary embodiment, the hole-injecting layer 332 is formed of a material selected from the group consisting of MTDATA, CuPc, TCTA, NPB (NPD), HATCN, TDAPB, PEDOT / PSS, F4TCNQ, N- (biphenyl- -Dimethyl-N- (4- (9-phenyl-9H-carbazol-3-yl) phenyl) -9H-fluorene-2-amine and the like. In another exemplary embodiment, the hole injection layer 532 may be formed by doping about 0.1 to 50% by weight of the above-described hole injecting material into the organic compounds represented by the general formulas (1) to (2).

In another exemplary embodiment, the hole injection layer 332 may include a hole injection layer (not shown) made of the hole injection material described above, a hole injection layer (not shown) doped with a hole injection material And an injection layer (not shown).

The first hole transport layer 334 is located between the hole injection layer 332 and the first light emitting material layer 336 and the first light emitting material layer 336 is located between the first hole transporting layer 334 and the first electron transporting layer 338 And the first electron transporting layer 338 is located between the first light emitting material layer 336 and the charge generating layer 350.

The second light emitting unit 340 includes a second hole transporting layer 344, a second light emitting material layer 344, a second electron transporting layer 346, And an injection layer 348.

The second light emitting material layer 344 is located between the second hole transport layer 342 and the second electrode 320 and the second electron transporting layer 346 is located between the second electrode layer 320 and the second light emitting material layer 344. [ And the electron injection layer 348 is located between the second electron transport layer 346 and the second electrode 320.

Each of the first and second emissive material layers 336 and 344 may be doped with a host to emit light of different colors. For example, the first light emitting material layer 336 emits blue (B), red (R), green (G), or yellow (Y) , Green (G), blue (B), and yellow-green (YG) light emitting material layers. In one exemplary embodiment, the first emissive material layer 336 emits blue light and the second emissive material layer 344 emits green, yellow-green (YG), or orange . For example, the second case of the luminescent material layer 344 constitutes a yellow-green light emitting material layer, the first and the CBP can be used as the host material of the second luminescent material layer 344, dopants such as Ir (2-phq) ₃ Can be used.

Each of the first and second hole transporting layers 334 and 342 is made of an organic compound represented by any one of Chemical Formulas 1 to 2 or doped with a hole transporting dopant such as TPD, . In an alternative embodiment, the first and second hole transporting layers 334 and 342 each include a hole transporting layer (not shown) composed only of organic compounds represented by Formulas 1 to 2 and organic compounds represented by Formulas 1 to 2 (Not shown) in which a hole transporting dopant is doped with a hole transporting layer (not shown). The first and second hole transporting layers 334 and 342 may be made of the same material or may be made of different materials.

Each of the first and second electron transporting layers 338 and 346 may comprise at least one of oxadiazole, triazole, phenanthroline, benzoxazole, benzthiazole, (For example, 2- [4- (9,10-Di-2-naphthalenyl-2-anthracenyl) phenyl] -1-phenyl-1H-benzimidazole. The first and second electron transporting layers 338 and 346 may each include a dopant such as an alkali metal or an alkaline earth metal. The first and second electron transporting layers 338 and 346 may be formed of the same material or may be made of different materials.

The electron injection layer 348 may be formed of an alkali halide based material such as LiF, CsF, NaF, or BaF ₂ and / or an organic metal based material such as lithium quinolate (Liq), lithium benzoate, sodium stearate, ≪ / RTI >

The charge generating layer 350 is disposed between the first light emitting unit 330 and the second light emitting unit 340 and includes an N type charge generating layer N-CGL 352 adjacent to the first light emitting unit 330, And a P-type charge generating layer (P-CGL) 354 adjacent to the second light emitting unit 340. The N type charge generation layer 352 supplies electrons to the first light emitting unit 330 and the P type charge generation layer 354 supplies holes to the second light emitting unit 340.

The N type charge generating layer 352 may be an organic layer doped with an alkali metal such as Li, Na, K, Cs and / or an alkaline earth metal such as Mg, Sr, Ba, or Ra. For example, the host organics used in the N-type charge generation layer 352 include 4,7-dipheny-1,10-phenanthroline (Bphen), MTDATA And the alkali metal or alkaline earth metal may be doped to about 0.01 to 30 wt%.

The P-type charge generation layer 354 may include an organic compound represented by the general formulas (1) to (2). For example, the P-type charge generation layer 354 may be formed of an organic compound represented by Chemical Formula 1 to Chemical Formula 2, or a hole injecting material such as MTDATA, CuPc, TCTA, NPB (NPD) , HATCN, TDAPB, PEDOT / PSS, F4TCNQ and / or N- (biphenyl-4-yl) -9,9- Phenyl) -9H-fluorene-2-amine. When the P-type charge generation layer 354 includes a hole injecting material and an organic compound of the formula 1 to 2, the hole injecting material may be doped to about 0.1 to 50% by weight. However, the present invention is not limited thereto no.

Although not shown in the drawing, a second hole (not shown) is formed between the P type charge generation layer 354 and the second hole transport layer 342 and / or between the N type charge generation layer 352 and the P type charge generation layer 354 An injection layer (upper hole injection layer; not shown) may be located. When the second hole injection layer is adopted, the holes generated in the P-type charge generation layer 354 can be efficiently injected and transferred to the second light emitting unit 340.

(Biphenyl-4-yl) -9,9-dimethyl-N- (4-fluorophenyl) (9-phenyl-9H-carbazol-3-yl) phenyl) -9H-fluorene-2-amine and the like, The compound may be doped with about 0.1 to 50 wt% of these hole injecting materials. The first hole injection layer 332 and the second hole injection layer (not shown) may be formed of the same material or different materials.

As described above, the organic compound of the present invention has a wide band gap, and is excellent in thermal stability and hole transporting ability. Accordingly, a second hole transport layer 342 made of an organic compound represented by any one of Chemical Formulas 1 to 2, or an organic material having a hole injection material or a hole transporting material doped in the organic compound of Chemical Formulas 1 and 2, The light emitting diode 300 having the tandem structure adopting the layer 354 and / or the second hole injection layer (not shown) can lower the driving voltage and can be used for white light emission. That is, the organic compound according to the present invention can drive the light emitting diode 300 at a low voltage, improve the lifetime of the light emitting diode 300, and improve the light emitting efficiency.

4 is a schematic cross-sectional view of a light emitting diode according to a fourth exemplary embodiment of the present invention. 4, a light emitting diode 400 according to a fourth embodiment of the present invention includes a first electrode 410 and a second electrode 420 facing each other, a first electrode 410 and a second electrode 410 facing each other, A second light emitting unit (upper light emitting unit) 440 positioned between the first light emitting unit 430 and the second electrode 420, and a second light emitting unit And a charge generating layer 450 positioned between the first and second light emitting units 430 and 440.

As described above, the first electrode 410 is made of a conductive material having a relatively large work function value, and the second electrode 420 is made of a conductive material having a relatively low work function.

The first light emitting unit 430 includes a hole injection layer (first hole injection layer) 432, a first hole transport layer (lower hole transport layer) 434, a first electron blocking layer (lower electron blocking layer) 435, , A first light emitting material layer (a lower light emitting material layer) 436, and a first electron transporting layer (a lower electron transporting layer 438).

The hole injection layer 432 is located between the first electrode 410 and the first light emitting material layer 436 and the first hole transporting layer 434 is disposed between the first hole injecting layer 432 and the first light emitting material layer 432. [ 436, and the first electron blocking layer 435 is located between the first hole transport layer 434 and the first light emitting material layer 436. That is, the first electron blocking layer 435 may be positioned between the first electrode 410 and the first light emitting material layer 436 to prevent electrons from moving independently of the hole layers 432 and 434.

The first emissive layer 436 is disposed between the first electron blocking layer 435 and the first electron transporting layer 438 and the first electron transporting layer 438 is disposed between the first emissive layer 436 and the first electron transporting layer 438. [ Product layer 450. [0050] Although not shown, a lower hole blocking layer that can prevent the movement of holes may be positioned between the first light emitting material layer 436 and the first electron transporting layer 438.

The second light emitting unit 440 includes a second hole transporting layer (upper hole transporting layer) 442, a second electron blocking layer (upper electron blocking layer) 443, a second light emitting material layer , A second electron transporting layer (upper electron transporting layer) 646, and an electron injecting layer 648. The second hole transport layer 442 is located between the charge generation layer 450 and the second light emitting material layer 444 and the second electron blocking layer 443 is located between the second hole transport layer 442 and the second light emitting material layer 444). That is, a second electron blocking layer 443 for preventing the movement of electrons independently from the second hole transporting layer 442 may be disposed between the charge generating layer 450 and the second light emitting material layer 444.

The second electron transport layer 446 is located between the second light emitting material layer 444 and the second electrode 420 and the electron injection layer 448 is located between the second electron transport layer 446 and the second electrode 420 Located. Although not shown, an upper hole blocking layer that can prevent the movement of holes may be located between the second light emitting material layer 444 and the second electron transporting layer 446, and the P type charge generating layer 454 and the A second hole injection layer (not shown) may be positioned between the second hole transport layer 442 and / or between the N-type charge generation layer 452 and the P-type charge generation layer 454.

Each of the first and second emissive material layers 436 and 444 may be formed by doping a host with a dopant and emitting different colors. For example, the first light emitting material layer 436 emits blue (B), red (R), green (G), or yellow (Y) , Green (G), blue (B), and yellow-green (YG) light emitting material layers. In one exemplary embodiment, the first emissive material layer 436 emits blue light and the second emissive material layer 444 emits green, yellow-green (YG), or orange . For example, the second case of the luminescent material layer 444 constitutes a yellow-green light emitting material layer, the first and the CBP can be used as the host material of the second luminescent material layer 344, dopants such as Ir (2-phq) ₃ Can be used.

Each of the first hole injection layer 432 and the second hole injection layer (not shown) may be formed by a combination of MTDATA, CuPc, TCTA, NPB (NPD), HATCN, TDAPB, PEDOT / PSS, F4TCNQ, -9,9-dimethyl-N- (4- (9-phenyl-9H-carbazol-3-yl) phenyl) -9H- Or doped with about 0.1 to 50% by weight of a hole injecting material in the organic compounds of the formulas (1) to (2). In another exemplary embodiment, the first hole injection layer 432 and the second hole injection layer (not shown) may be formed using the hole injection layer (not shown) made of the above-described hole injection material) And a separate hole injection layer (not shown) in which an organic compound is doped with a hole injection material. The first hole injection layer 432 and the second hole injection layer (not shown) may be formed of the same material or may be made of different materials.

Each of the first and second hole transporting layers 434 and 442 is made of an organic compound represented by any one of Chemical Formulas 1 to 2 or doped with a hole transporting dopant such as TPD, . In an alternative embodiment, the first and second hole transporting layers 434 and 442 are formed of a hole transporting layer (not shown) composed only of the organic compound represented by Chemical Formulas 1 to 2 and an organic compound (Not shown) in which a hole transporting dopant is doped with a hole transporting layer (not shown). The first and second hole transporting layers 434 and 442 may be made of the same material or may be made of different materials.

Each of the first and second electron blocking layers 435 and 443 may be formed of an organic compound represented by Chemical Formula 1 to Chemical Formula 2. The first and second electron blocking layers 435 and 443 may be made of the same material or may be made of different materials.

Each of the first and second electron transporting layers 438 and 446 may comprise at least one of oxadiazole, triazole, phenanthroline, benzoxazole, benzthiazole, (For example, 2- [4- (9,10-Di-2-naphthalenyl-2-anthracenyl) phenyl] -1-phenyl-1H-benzimidazole. The first and second electron transporting layers 438 and 446 may each comprise a dopant such as an alkali metal or an alkaline earth metal. The first and second electron transporting layers 438 and 446 may be made of the same material or may be made of different materials.

The electron injection layer 448 may be formed of an alkali halide material such as LiF, CsF, NaF, or BaF ₂ and / or an organometallic material such as lithium quinolate (Liq), lithium benzoate, sodium stearate, ≪ / RTI >

The charge generating layer 450 is disposed between the first light emitting unit 430 and the second light emitting unit 440 and includes an N-type charge generating layer (N-CGL) 452 adjacent to the first light emitting unit 430 And a P-type charge generation layer (P-CGL) 454 adjacent to the second light emitting unit 440. The N type charge generation layer 452 supplies electrons to the first light emitting unit 430 and the P type charge generation layer 454 supplies holes to the second light emitting unit 440.

The N type charge generating layer 452 may be an alkali metal such as Li, Na, K, Cs or an organic layer doped with an alkaline earth metal such as Mg, Sr, Ba, or Ra. The host organics used for the N type charge generating layer 452 may be a material such as Bphen, MTDATA, and the alkali metal or alkaline earth metal may be doped to about 0.01 to 30 weight percent.

The P-type charge generation layer 454 may include an organic compound represented by Chemical Formulas 1 to 2. For example, the P-type charge generation layer 454 may be formed of an organic compound represented by Chemical Formula 1 to Chemical Formula 2, or may be formed by injecting a hole injecting material such as MTDATA, CuPc, TCTA, NPB (NPD) , HATCN, TDAPB, PEDOT / PSS, F4TCNQ and / or N- (biphenyl-4-yl) -9,9- Phenyl) -9H-fluorene-2-amine. When the P-type charge generation layer 454 contains a hole injecting material and an organic compound of the formula 1 to 2, the hole injecting material may be doped to about 0.1 to 50% by weight. However, the present invention is not limited thereto no.

As described above, the organic compound of the present invention has a wide band gap, and is excellent in thermal stability and hole transporting ability. Therefore, a second hole transport layer 442 made of an organic compound represented by any one of formulas (1) and (2) or composed of an organic compound doped with a hole injection material or a hole transporting dopant, The light emitting diode 400 having a tandem structure adopting the first hole injection layer 443, the P type charge generation layer 454 and / or the second hole injection layer (not shown) may be used for white light emission. Using the organic compound according to the present invention, the light emitting diode 400 can be driven at a low voltage, the lifetime of the light emitting diode 400 can be improved, and the luminous efficiency can be improved.

5 is a schematic cross-sectional view of a light emitting diode according to an exemplary fifth embodiment of the present invention. 5, a light emitting diode 500 according to a fifth embodiment of the present invention includes a first electrode 510 and a second electrode 520 facing each other, a first electrode 510 and a second electrode 510, A second light emitting unit (upper light emitting unit) 540 positioned between the first light emitting unit 530 and the second electrode 520, and a second light emitting unit And a charge generating layer 550 located between the first and second light emitting units 530 and 540.

As described above, the first electrode 510 is made of a conductive material having a relatively large work function value and the second electrode 520 is made of a conductive material having a negative work function and a relatively low work function value.

The first light emitting unit 530 includes a hole injection layer (first hole injection layer) 532, a hole transport layer 534, a first electron blocking layer 535, a first light emitting material layer , 536) and a first electron transporting layer (lower electron transporting layer, 538).

The hole injection layer 532 is located between the first electrode 510 and the first light emitting material layer 536 and the hole transporting layer 534 is disposed between the hole injecting layer 532 and the first light emitting material layer 536 And the first electron blocking layer 535 is located between the hole transporting layer 534 and the first light emitting material layer 536. That is, a first electron blocking layer 535 for preventing the movement of electrons independently from the hole blocking layers 532 and 534 may be disposed between the first electrode 510 and the first light emitting material layer 536.

The first emissive layer 536 is disposed between the first electron blocking layer 535 and the first electron transporting layer 538 and the first electron transporting layer 538 is disposed between the first emitting layer 536 and the charge generating layer 538. [ (Not shown). Although not shown, a first hole blocking layer (lower hole blocking layer) capable of preventing the movement of holes may be positioned between the first light emitting material layer 536 and the first electron transporting layer 538.

The second light emitting unit 440 includes a second electron blocking layer (upper electron blocking layer) 543, a second light emitting material layer (upper light emitting material layer) 544, a second electron transporting layer , And an electron injection layer (548). The second electron blocking layer 543 is located between the charge generating layer 550 and the second light emitting material layer 544. That is, a second electron blocking layer 543, which prevents electron migration, may be positioned between the charge generating layer 550 and the second light emitting material layer 544.

The second electron transport layer 546 is located between the second light emitting material layer 544 and the second electrode 520 and the electron injection layer 548 is located between the second electron transport layer 546 and the second electrode 520 Located. Although not shown, a second hole blocking layer (upper hole blocking layer) that can prevent the movement of holes may be located between the second light emitting material layer 544 and the second electron transporting layer 546, and a P type charge A second hole injection layer (not shown) may be positioned between the resultant layer 554 and the second electron blocking layer 543 and / or between the N-type charge generation layer 552 and the P-type charge generation layer 554 have.

Each of the first and second light emitting material layers 536 and 544 may be doped with a host to emit light of different colors. For example, the first light emitting material layer 536 emits blue (B), red (R), green (G), or yellow (Y) , Green (G), blue (B), and yellow-green (YG) light emitting material layers. In one exemplary embodiment, the first emissive material layer 536 emits blue light and the second emissive material layer 544 emits green, yellow-green (YG), or orange . For example, the second case of the luminescent material layer 544 constitutes a yellow-green light emitting material layer, the first and the CBP can be used as the host material of the second luminescent material layer 544, dopants such as Ir (2-phq) ₃ Can be used.

Each of the first hole injection layer 532 and the second hole injection layer (not shown) may be formed of a material selected from the group consisting of MTDATA, CuPc, TCTA, NPB (NPD), HATCN, TDAPB, PEDOT / PSS, F4TCNQ, -9,9-dimethyl-N- (4- (9-phenyl-9H-carbazol-3-yl) phenyl) -9H- Or doped with about 0.1 to 50% by weight of a hole injecting material in the organic compounds of the formulas (1) to (2). In yet another exemplary embodiment, the first hole injection layer 532 and the second hole injection layer (not shown) may be formed using the hole injection layer (not shown) made of the above-described hole injection material) And a separate hole injection layer (not shown) in which an organic compound is doped with a hole injection material. The first hole injection layer 532 and the second hole injection layer (not shown) may be formed of the same material or may be made of different materials.

The hole transport layer 534 may be made of organic compounds of the formulas (1) to (2), or may be doped with a hole transporting dopant such as TPD, NPD or CBP. In an alternative embodiment, the hole transport layer 534 includes a hole transport layer (not shown) consisting only of an organic compound represented by Chemical Formula 1 to Chemical Formula 2, and a hole transport layer (not shown) doped with a hole transporting dopant in the organic compound represented by Chemical Formula 1 to Chemical Formula 2 And a separate hole transport layer (not shown).

Each of the first and second electron blocking layers 535 and 543 may be formed of an organic compound represented by Chemical Formulas 1 to 2. The first and second electron blocking layers 535 and 543 may be made of the same material or may be made of different materials.

Each of the first and second electron transporting layers 538 and 546 may comprise at least one of oxadiazole, triazole, phenanthroline, benzoxazole, benzthiazole, (For example, 2- [4- (9,10-Di-2-naphthalenyl-2-anthracenyl) phenyl] -1-phenyl-1H-benzimidazole. The first and second electron transporting layers 538 and 546 may each include a dopant such as an alkali metal or an alkaline earth metal. The first and second electron transporting layers 538 and 546 may be made of the same material or may be made of different materials.

The electron injection layer 548 may be formed of an alkali halide based material such as LiF, CsF, NaF, BaF ₂ and / or an organic metal based material such as lithium quinolate (Liq), lithium benzoate, sodium stearate, ≪ / RTI >

The charge generating layer 550 is disposed between the first light emitting unit 530 and the second light emitting unit 540 and includes an N type charge generating layer N-CGL 552 adjacent to the first light emitting unit 530, And a P-type charge generation layer (P-CGL) 554 adjacent to the second light emitting unit 540. The N type charge generating layer 552 supplies electrons to the first light emitting unit 530 and the P type charge generating layer 554 supplies holes to the second light emitting unit 540.

The N type charge generating layer 552 may be an organic layer doped with an alkali metal such as Li, Na, K, Cs or an alkaline earth metal such as Mg, Sr, Ba, or Ra. The host organics used in the N-type charge generating layer 552 may be a material such as Bphen, MTDATA, and the alkali metal or alkaline earth metal may be doped to about 0.01 to 30% by weight.

The P-type charge generation layer 554 may include an organic compound represented by the general formulas (1) to (2). For example, the P type charge generation layer 554 may be formed of an organic compound represented by Chemical Formula 1 to Chemical Formula 2, or a hole injecting material such as MTDATA, CuPc, TCTA, NPB (NPD) , HATCN, TDAPB, PEDOT / PSS, F4TCNQ and / or N- (biphenyl-4-yl) -9,9- Phenyl) -9H-fluorene-2-amine. Preferably, the P-type charge generation layer 554 may be formed by doping a hole injecting material into the organic compound of Chemical Formulas 1 to 2. When the P-type charge generating layer 554 contains the hole injecting material and the organic compound of the formula 1 to 2, the hole injecting material may be doped to about 0.1 to 50% by weight. However, the present invention is not limited thereto no.

As described above, the organic compound of the present invention has a wide band gap, and is excellent in thermal stability and hole transporting ability. Therefore, a second electron blocking layer 543 made of an organic compound represented by any one of formulas (1) and (2), or an organic compound doped with a hole injecting material or a hole transporting dopant, The tandem light emitting diode 500 adopting the layer 554 and / or the second hole injection layer (not shown) may be used for white light emission. By using the organic compound according to the present invention, the light emitting diode 500 can be driven at a low voltage, the life of the light emitting diode 500 can be improved, and the luminous efficiency can be improved.

3 to 5 illustrate that the P-type charge generation layer includes the organic compounds of the formulas (1) to (2). However, as shown in FIGS. 1 and 2, the hole injection layer, the hole transport layer, and / And organic compounds represented by formulas (1) to (2). In addition, although the first and second light emitting units are stacked and the charge generating layer is disposed therebetween in FIGS. 3 to 5, it is possible to further include a charge generating layer located between the additional light emitting unit and the light emitting units have.

Next, a display device to which the light emitting diode of the present invention is applied will be described. 6 is a schematic cross-sectional view of an organic light emitting diode display device according to an exemplary embodiment of the present invention.

6, the organic light emitting diode display 600 includes a driving thin film transistor Td, a planarization layer 660 covering the driving thin film transistor Td, And a light emitting diode E connected to the thin film transistor Td. The driving thin film transistor Td includes a semiconductor layer 640, a gate electrode 644, a source electrode 656 and a drain electrode 658. In FIG. 6, the driving thin film transistor Td has a coplanar structure And a transistor Td.

The first substrate 601 constituting the array substrate and the second substrate 602 facing the first substrate 601 are adhered together to form a display panel. The first substrate 601 and the second substrate 602 may be a glass substrate, a thin flexible substrate, or a polymer plastic substrate. The first substrate 601 on which the driving thin film transistor Td and the light emitting diode E on which the organic light emitting layer 620 is formed forms an array substrate. The first substrate 601 is encapsulated by a second substrate 602 called an in-cap substrate. The first substrate 601 and the second substrate 602 are adhered together by an adhesive 680 made of a sealant or a frit along the edges of the first substrate 601 and the second substrate 602, Lt; / RTI >

A semiconductor layer 640 is formed on the first substrate 601. For example, the semiconductor layer 640 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 640. The light shielding pattern prevents light from being incident on the semiconductor layer 640, Thereby preventing deterioration of the semiconductor device. Alternatively, the semiconductor layer 640 may be made of polycrystalline silicon. In this case, impurities may be doped on both edges of the semiconductor layer 640.

A gate insulating layer 642 made of an insulating material is formed on the entire surface of the first substrate 601 on the semiconductor layer 640. A gate insulating film 642 may be formed of an inorganic insulating material such as silicon oxide (SiO ₂₎ or silicon nitride (SiNx).

A gate electrode 644 made of a conductive material such as metal is formed on the gate insulating layer 642 to correspond to the center of the semiconductor layer 640. A gate wiring (not shown) and a first capacitor electrode (not shown) may be formed on the gate insulating film 642. The gate wiring may extend along the first direction, and the first capacitor electrode may be connected to the gate electrode 644. [ The gate insulating layer 642 is formed on the entire surface of the first substrate 601. The gate insulating layer 642 may be patterned to have the same shape as the gate electrode 644. [

An interlayer insulating film 650 made of an insulating material is formed on the entire surface of the first substrate 601 on the gate electrode 644. An interlayer insulating film 650 is formed of an organic insulating material such as silicon oxide (SiO ₂₎ or may be formed of an inorganic insulating material such as silicon nitride (SiNx), benzocyclobutene (benzocyclobutene) or the picture acrylate (photo-acryl) .

The interlayer insulating film 650 has first and second semiconductor layer contact holes 652 and 654 that expose both upper surfaces of the semiconductor layer 640. The first and second semiconductor layer contact holes 652 and 654 are spaced apart from the gate electrode 644 on both sides of the gate electrode 644. Here, the first and second semiconductor layer contact holes 652 and 654 are also formed in the gate insulating film 642. Alternatively, when the gate insulating film 642 is patterned in the same shape as the gate electrode 644, the first and second semiconductor layer contact holes 652 and 654 are formed only in the interlayer insulating film 650.

A source electrode 656 and a drain electrode 658 made of a conductive material such as metal are formed on the interlayer insulating layer 650. A data line (not shown) and a power supply line (not shown) and a second capacitor electrode (not shown) extending along the second direction may be formed on the interlayer insulating layer 650.

The source electrode 656 and the drain electrode 658 are spaced apart from each other around the gate electrode 644 and are connected to both sides of the semiconductor layer 640 through the first and second semiconductor layer contact holes 652 and 654, 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 658 and overlaps the first capacitor electrode to form a storage capacitor with the dielectric layer 650 between the first and second capacitor electrodes as a dielectric layer.

On the other hand, the semiconductor layer 640, the gate electrode 644, the source electrode 656, and the drain electrode 658 constitute a driving thin film transistor Td. The driving thin film transistor Td illustrated in FIG. 6 has a coplanar structure in which a gate electrode 644, a source electrode 656, and a drain electrode 658 are disposed on a semiconductor layer 640. 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) having substantially the same structure as the driving thin film transistor Td is further formed on the first substrate 601. [ The gate electrode 644 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 656 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.

Meanwhile, the organic light emitting diode display 600 may include a color filter (not shown) that absorbs light generated in the light emitting diode E. For example, a color filter (not shown) can absorb red (R), green (G), blue (B), and white (W) light. In this case, a color filter pattern of red, green, and blue that absorbs light may be separately formed for each pixel region, and each of the color filter patterns may include a light emitting diode E The organic light emitting layer 620 may be disposed to overlap with each other. By adopting a color filter (not shown), the organic light emitting diode display 600 can realize full-color.

For example, when the organic light emitting diode display 600 is a bottom emission type, a color filter (not shown) for absorbing light may be disposed on the interlayer insulating layer 650 corresponding to the light emitting diode E. In an alternative embodiment, when the organic light emitting display 600 is a top emission type, the color filter may be located on top of the light emitting diode E, that is, above the second electrode 630. As an example, a color filter (not shown) may be formed to a thickness of 2 to 5 mu m. In this case, the light emitting diode E may be a white light emitting diode having a tandem structure as shown in FIG. 3 to FIG.

A planarization layer 660 is formed on the entire surface of the first substrate 601 over the source electrode 656 and the drain electrode 658. The planarization layer 660 is flat on the top and has a drain contact hole 662 for exposing the drain electrode 658 of the driving thin film transistor Td. Here, the drain contact hole 662 is formed directly on the second semiconductor layer contact hole 654, but may be formed apart from the second semiconductor layer contact hole 654.

The light emitting diode E includes a first electrode 610 located on the planarization layer 660 and connected to a drain electrode 658 of the driving thin film transistor Td and a first electrode 610 which is sequentially stacked on the first electrode 610. [ A light emitting layer 620 and a second electrode 630. As described above, the first electrode 610 is made of a material having a relatively large work function value and serves as an anode, and the second electrode 630 is made of a material having a relatively low work function value to serve as a cathode.

A second substrate 602, which is an encapsulation substrate that covers the light emitting diode E, is bonded to the first substrate 601 through an adhesive 680. Although not shown, a barrier layer may be formed between the second substrate 602 and the light emitting diode E to prevent adhesion of moisture or oxygen to the light emitting diode E by attaching the substrates.

As described with reference to the exemplary embodiments of Figs. 1 to 5, the organic luminescent layer 620 can be formed by laminating the organic compound represented by Chemical Formula 1 to Chemical Formula 2 as a hole layer, an electron blocking layer and / . For example, the organic light emitting layer 620 may include a light emitting material layer, a hole injecting layer, a hole transporting layer, an electron transporting layer, an electron injecting layer, a charge generating layer, And an electron blocking layer.

Whether or not the organic compounds represented by formulas (1) to (2) are applied to the display device can be confirmed by the following method. A display panel is decapped in an organic light emitting diode display device and an organic layer is separated by cutting a cross section of a light emitting diode among display panels divided into a substrate, an electrode, and an organic layer. The material of the organic material layer is identified by an analytical method such as thin-layer chromatography, and the material of each organic material layer is separated. Subsequently, materials can be identified using organic chemical analysis tools for each organic layer. For example, the NMR (1D, 2D) analysis can confirm the binding relationship of carbon, hydrogen, etc. of the compound used in the organic material layer, and the molecular weight of the compound used in the organic material layer can be confirmed using a mass spectrometer , Fourier transform infrared spectroscopy (Fourier transform infrared spectroscopy; FT-IR), infrared spectroscopy can be used to identify the functional group of the compound used in the organic layer. In addition, elements constituting each compound can be analyzed using an elemental analyzer (EA), and X-ray analysis such as X-ray diffraction (XRD) Structure can be determined and analyzed. By using such an organic chemical analysis tool, it can be confirmed whether or not the organic compound represented by Chemical Formulas 1 to 2 is applied to a display device.

As described above, the organic compound of the present invention has a wide band gap, and is excellent in thermal stability and hole transporting property. Therefore, the organic compound of the present invention can be applied to a hole layer and / or an electron blocking layer. For example, when the organic compound of the present invention is used alone or in combination with a hole injecting material or a hole transporting material, the hole transporting property to the organic light emitting layer 620 is improved. In addition, when the organic compound of the present invention is used in the P type charge generation layer in a light emitting diode having a tandem structure, it can be applied to transfer the generated charges to the adjacent common layer. By applying the organic compound according to the present invention to the light emitting diode (E), the light emitting diode (E) can be driven at a low voltage, the lifetime of the light emitting diode (E) can be improved and the light emitting efficiency 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 A1

1) Compound G2 Synthesis

To a 500 mL round bottom flask was added R1 (5.00 g, 29.55 mmol), G1 (10.47 g, 32.50 mmol), Tris (dibenzylideneacetone) dipalladium (0) (0.41 g, 0.44 mmol) (diphenylphosphino) -1,1'-binaphthalene (BINAP) (0.55 g, 0.89 mmol) and sodium tert-butoxide (3.98 g, 41.37 mmol) were dissolved in toluene (250 mL) After completion of the reaction, toluene was removed, and the residue was extracted with dichloromethane and water. The residue was subjected to vacuum distillation. The silica gel column was distilled under reduced pressure to obtain Compound G2 (7.53 g, 18.3 mmol).

2) Synthesis of Compound A1

To a 100 mL round bottom flask was added S1 (2.00 g, 4.11 mmol), G2 (1.06 g, 4.52 mmol), Tris (dibenzylideneacetone) dipalladium (0) (0.06 g, 0.06 mmol), Tri- and sodium tert-butoxide (0.55 g, 5.75 mmol) were dissolved in toluene (40 mL) and stirred at 100 ° C in a bath for 24 hours. After completion of the reaction, toluene was removed and dichloromethane and water were used The extract was concentrated, and the column was separated using ethyl acetate and n-hexane. Thereafter, a precipitate was formed using dichloromethane and petroleum ether, and then filtered to obtain Compound A1 (1.80 g, 2.78 mmol). The NMR analysis results of the synthesized Al compound are shown in Fig.

Synthesis Example 2: Synthesis of A2 compound

1) Compound G4 Synthesis

(3.00 g, 17.73 mmol), G3 (7.77 g, 19.50 mmol), Tris (dibenzylideneacetone) dipalladium (0) (0.24 g, 0.27 mmol), (±) -2,2'-Bis (2.33 g, 24.82 mmol) and diphenylphosphino-1,1'-binaphthalene (BINAP) (0.33 g, 0.53 mmol) were dissolved in toluene (150 mL) After completion of the reaction, toluene was removed, and the residue was extracted with dichloromethane and water. The residue was subjected to vacuum distillation. The silica gel column was distilled under reduced pressure to obtain Compound G4 (6.05 g, 12.43 mmol).

2) Synthesis of Compound A2

To a 250 ml round bottom flask was added S1 (3.00 g, 15.73 mmol), G4 (10.57 g, 19.50 mmol), Tris (dibenzylideneacetone) dipalladium (0) (0.14 g, 0.22 mmol) diphenylphosphino) -1,1'-binaphthalene (BINAP) (0.23 g, 0.53 mmol) and sodium tert-butoxide (2.39 g, 24.82 mmol) were dissolved in 150 mL of toluene and stirred at 100 ° C. for 24 hours. After completion of the reaction, toluene was removed, and the residue was extracted with dichloromethane and water. The residue was subjected to vacuum distillation. The silica gel column was distilled under reduced pressure to obtain Compound A2 (6.05 g, 12.43 mmol). NMR analysis results of the synthesized A2 compound are shown in Fig.

Synthesis Example 3: Synthesis of Compound A3

One) Compound G6 Synthesis

To a 250 mL round bottom flask was added R1 (3.00 g, 12.23 mmol), G5 (3.22 g, 11.80 mmol), Tris (dibenzylideneacetone) dipalladium (0) (0.17 g, 0.18 mmol) (1.25 g, 17.12 mmol) and diphenylphosphino-1,1'-binaphthalene (BINAP) (0.23 g, 0.37 mmol) and sodium tert-butoxide were dissolved in toluene (120 mL) After completion of the reaction, toluene was removed, and the residue was extracted with dichloromethane and water. The residue was subjected to vacuum distillation. The silica gel column was distilled under reduced pressure to obtain Compound G6 (3.80 g, 8.68 mmol)

2) Compound A3 Synthesis

To a 250 mL round bottom flask was added S1 (3.00 g, 17.73 mmol), G6 (5.77 g, 12.50 mmol), Tris (dibenzylideneacetone) dipalladium (0) (0.24 g, 0.27 mmol) (2.33 g, 24.82 mmol) and diphenylphosphino-1,1'-binaphthalene (BINAP) (0.33 g, 0.53 mmol) were dissolved in toluene (150 mL) After completion of the reaction, toluene was removed, and the residue was extracted with dichloromethane and water. The residue was subjected to vacuum distillation. The silica gel column was distilled under reduced pressure to obtain Compound A3 (7.05 g, 14.43 mmol). The NMR analysis results of the synthesized A3 compound are shown in Fig.

Synthesis Example 4 Synthesis of A4 Compound

1) Compound G8 Synthesis

To a 250 mL round bottom flask was added R2 (3.00 g, 12.23 mmol), G7 (3.22 g, 11.80 mmol), Tris (dibenzylideneacetone) dipalladium (0) (0.17 g, 0.18 mmol) (1.25 g, 17.12 mmol) and diphenylphosphino-1,1'-binaphthalene (BINAP) (0.23 g, 0.37 mmol) and sodium tert-butoxide were dissolved in toluene (120 mL) After completion of the reaction, toluene was removed, and the residue was extracted with dichloromethane and water. The residue was subjected to vacuum distillation. The silica gel column was distilled under reduced pressure to obtain Compound G8 (3.40 g, 8.52 mmol).

2) Compound A4 Synthesis

To a 100 mL round bottom flask was added S1 (1.50 g, 3.43 mmol), G8 (0.88 g, 3.77 mmol), Tris (dibenzylideneacetone) dipalladium (0) (0.05 g, 0.05 mmol), Tri- and sodium tert-butoxide (0.46 g, 4.80 mmol) were dissolved in toluene (50 mL) and stirred at 100 ° C. in a bath for 24 hours. After completion of the reaction, toluene was removed and dichloromethane and water were used , Concentrated, and separated by column using ethyl acetate and n-hexane. Thereafter, a precipitate was formed using dichloromethane and petroleum ether, and then filtered to obtain Compound A4 (2.15 g, 2.25 mmol). NMR analysis results of the synthesized A4 compound are shown in Fig.

Synthesis Example 5: Synthesis of B1 compound

To a 100 mL round bottom flask was added S2 (2.00 g, 4.11 mmol), G2 (1.23 g, 4.13 mmol), Tris (dibenzylideneacetone) dipalladium (0) (0.16 g, 0.16 mmol) and sodium tert-butoxide (0.55 g, 5.75 mmol) were dissolved in toluene (40 mL) and stirred at 100 ° C in a bath for 24 hours. After completion of the reaction, toluene was removed and dichloromethane and water were used , Concentrated, and separated by column using ethyl acetate and n-hexane. Thereafter, a precipitate was prepared using dichloromethane and petroleum ether, and then filtered to obtain Compound B1 (1.36 g, 2.58 mmol). The NMR analysis results of the synthesized B1 compound are shown in Fig.

Synthesis Example 6: Synthesis of B2 compound

To a 100 mL round bottom flask was added S2 (2.00 g, 4.11 mmol), G4 (1.37 g, 4.14 mmol), Tris (dibenzylideneacetone) dipalladium (0) (0.06 g, 0.06 mmol), Tri- and sodium tert-butoxide (0.55 g, 5.75 mmol) were dissolved in toluene (40 mL) and stirred at 100 ° C in a bath for 24 hours. After completion of the reaction, toluene was removed and dichloromethane and water were used , Concentrated, and separated by column using ethyl acetate and n-hexane. Thereafter, a precipitate was prepared using dichloromethane and petroleum ether, and then filtered to obtain Compound B2 (1.65 g, 2.13 mmol). NMR analysis results of the synthesized B2 compound are shown in Fig.

Synthesis Example 7: Synthesis of B3 compound

To a 100 mL round bottom flask was added S2 (2.00 g, 4.11 mmol), G6 (1.85 g, 4.12 mmol), Tris (dibenzylideneacetone) dipalladium (0) (0.06 g, 0.06 mmol), Tri- and sodium tert-butoxide (0.55 g, 5.75 mmol) were dissolved in toluene (40 mL) and stirred at 100 ° C in a bath for 24 hours. After completion of the reaction, toluene was removed and dichloromethane and water were used , Concentrated, and separated by column using ethyl acetate and n-hexane. Thereafter, the precipitate was made with dichloromethane and petroleum ether, and then filtered to obtain Compound B3 (1.7 g, 2.03 mmol). NMR analysis results of the synthesized B3 compound are shown in Fig.

Synthesis Example 8: Synthesis of B4 compound

To a 100 mL round bottom flask was added S2 (2.00 g, 4.11 mmol), G8 (1.82 g, 5.29 mmol), Tris (dibenzylideneacetone) dipalladium (0) (0.06 g, 0.06 mmol), Tri- and sodium tert-butoxide (0.55 g, 5.75 mmol) were dissolved in toluene (40 mL) and stirred at 100 ° C in a bath for 24 hours. After completion of the reaction, toluene was removed and dichloromethane and water were used , Concentrated, and separated by column using ethyl acetate and n-hexane. Thereafter, a precipitate was prepared by using dichloromethane and petroleum ether, followed by filtration to obtain Compound B4 (1.93 g, 2.95 mmol). The NMR analysis results of the synthesized B4 compound are shown in Fig.

Example 1: Fabrication of single-layer light-emitting diode

A light emitting diode device including the A1 compound synthesized in Synthesis Example 1 was prepared. The ITO glass was patterned so that the light emitting area of the indium-tin-oxide (ITO) glass was 3 mm x 3 mm and then cleaned. After transferring a substrate in a vacuum chamber, the base pressure of 10 ^-6 Torr the hole injection layer (HAT-CN, 50Å) on a ITO After that, a hole transport layer (α-NPB, 1000Å), the exciton blocking layer is an electron blocking layer (A1, 150 Å), a blue light emitting material layer (host MADN doped with 4 wt% of dopant BD-1, 250 Å), a first electron transport layer (2- [4- (9,10- an electron injecting layer (LiF, 5 ~ 10 Å), Al (800~1000 Å), and a second electron transporting layer (Li doped with 2% Bphen, 100 Å) .

After deposition, the films were transferred from the deposition chamber into a dry box for subsequent film formation and subsequently encapsulated using a UV cured epoxy and a moisture getter. This organic light emitting diode has an emission area of 9 mm ² .

Example 2: Fabrication of single-layer light-emitting diode

The procedure of Example 1 was repeated except that A2 synthesized in Synthesis Example 2 was used in place of A1 in the exciton blocking layer to prepare a light emitting diode.

Example 3: Fabrication of single-layer light-emitting diode

The procedure of Example 1 was repeated except that A3 synthesized in Synthesis Example 3 was used in place of A1 in the exciton blocking layer, to fabricate a light emitting diode.

Example 4: Fabrication of single-layer light-emitting diode

The procedure of Example 1 was repeated except that A4 of Synthesis Example 4 was used in place of A1 of the exciton blocking layer to prepare a light emitting diode.

Example 5: Fabrication of single-layer light-emitting diode

The procedure of Example 1 was repeated except that the B1 synthesized in Synthesis Example 5 was used in place of the A1 in the exciton blocking layer. Thus, a light emitting diode was fabricated.

Example 6: Fabrication of single-layer light-emitting diode

The procedure of Example 1 was repeated except that B2 synthesized in Synthesis Example 6 was used in place of A1 in the exciton blocking layer to prepare a light emitting diode.

Example 7: Fabrication of single-layer light-emitting diode

The procedure of Example 1 was repeated except that B3 synthesized in Synthesis Example 7 was used in place of A1 in the exciton blocking layer, thereby preparing a light emitting diode.

Example 8: Fabrication of single-layer light-emitting diode

The procedure of Example 1 was repeated except that B4 synthesized in Synthesis Example 8 was used in place of A1 in the exciton blocking layer, thereby preparing a light emitting diode.

Comparative Example 1: Fabrication of single-layer light-emitting diode

The procedure of Example 1 was repeated except that TCTA was used in place of Al of the exciton blocking layer to fabricate a light emitting diode.

Experimental Example 1: Evaluation of light emitting diode characteristics of a single layer structure

The properties of the light emitting diodes manufactured in Examples 1 to 8 and Comparative Example 1 were evaluated. The organic light emitting diodes manufactured in each of Examples 1 to 8 and Comparative Example 1 were connected to an external power source. (Cd / m2), current efficiency (Cd / A), power efficiency (lm / W), external quantum efficiency (EQE), color coordinates) of all the light emitting diodes manufactured in the present invention, Were evaluated at room temperature using a constant current source (KEITHLEY) and a photometer PR 650. The evaluation results are shown in Figs. 15A to 15C and Table 1 below. The light emitting diode using the organic compound of the present invention has a driving voltage reduced by up to 26%, a current efficiency of up to 83%, a power efficiency of up to 118%, and an external quantum efficiency Up to 108%. That is, it has been confirmed that the organic compound of the present invention can be used as an electron blocking layer of a single-layered light emitting diode, thereby lowering the driving voltage of the light emitting diode, and greatly improving the luminance and the luminous efficiency.

Example 9: Fabrication of tandem light emitting diode

A light emitting diode having a tandem structure including the A1 compound synthesized in Synthesis Example 1 was prepared. The ITO glass was patterned so that the light emitting area of the indium-tin-oxide (ITO) glass was 3 mm x 3 mm and then cleaned. After the substrate was transferred to the vacuum chamber, the base pressure was adjusted to 10 ^-6 Torr. Then, a hole injecting layer (HAT-CN; 50 Å), a lower hole transporting layer (α-NPB, 1000 Å) (TCTA, 150 Å), a blue light emitting material layer (Host MADN doped with 4 wt% of dopant BD-1, 250 Å), and a lower electron transport layer (2- [4- (9,10-Di- (HAT-CN, 100 Å), an upper hole transport layer (HAT-CN), and a hole transport layer (HAT-CN) (α-NPB, 100Å), the upper exciton blocking layer is an electron blocking layer (A1, 100Å), an upper light emitting material layer of YG luminescent material layer (Ir (2-phq), CBP, 300Å ₃ to 10% doping), upper An electron transporting layer (LiF, 5 to 10 Å), an electron transport layer (2- [4- (9,10-Di-2-naphthalenyl-2-anthracenyl) phenyl] Al (800 to 1000 ANGSTROM).

After deposition, the films were transferred from the deposition chamber into a dry box for subsequent film formation and subsequently encapsulated using a UV cured epoxy and a moisture getter. This organic light emitting diode has an emission area of 9 mm ² .

Example 10 Fabrication of Light Emitting Diode Element with Tandem Structure

The procedure of Example 9 was repeated except that A3 synthesized in Synthesis Example 3 was used instead of A1 in the upper exciton blocking layer to produce a light emitting diode of a tandem structure.

Example 11 Fabrication of Light Emitting Diode Element with Tandem Structure

The procedure of Example 9 was repeated except that B2 synthesized in Synthesis Example 6 was used instead of A1 in the upper exciton blocking layer to prepare a light emitting diode of a tandem structure.

Example 12 Fabrication of Light Emitting Diode Element with Tandem Structure

The procedure of Example 9 was repeated except that B4 synthesized in Synthesis Example 8 was used instead of A1 in the upper exciton blocking layer to prepare a light emitting diode of a tandem structure.

Comparative Example 2: Fabrication of a light emitting diode device having a multilayer structure

The procedure of Example 9 was repeated except that TCTA was used instead of Al of the upper exciton blocking layer to produce a multilayered LED device.

Experimental Example 2: Evaluation of Characteristics of Light Emitting Diodes with a Tandem Structure

The same procedure as in Experimental Example 1 was repeated to evaluate the characteristics of the tandem-type light emitting diodes manufactured in Examples 9 to 12 and Comparative Example 2, respectively. The evaluation results are shown in Figs. 16A to 16D and Table 2 below. The light emitting diode of the tandem structure in which the organic compound of the present invention is applied to the upper exciton blocking layer has a driving voltage reduced by up to 13% as compared with the light emitting diode of the tandem structure in which TCTA is applied to the upper exciton blocking layer in Comparative Example 2, Up to 24%, power efficiency up to 30% and external quantum efficiency up to 24%. That is, it has been confirmed that the organic compound of the present invention can be used as an electron blocking layer of a tandem light emitting diode, thereby lowering the driving voltage of the light emitting diode, and greatly improving the luminance and the luminous efficiency.

The results of Experimental Examples 1 and 2 indicate that the organic compound synthesized in the present invention is excellent in hole injection characteristics and hole transporting characteristics and therefore the organic compound synthesized in the present invention can be applied to improve the luminance of the light emitting diode, , Power efficiency and quantum efficiency can be improved and lifetime of the light emitting device can be improved by introducing a condensed aromatic ring having good thermal stability. Accordingly, the organic compound according to the present invention can be applied to a hole layer and / or an exciton blocking layer in a light emitting diode having a single layer structure, and can be applied to a hole layer, an exciton blocking layer and / or a charge generating layer in a light emitting diode having a tandem structure . The light emitting diode including the organic compound of the present invention exhibits a low driving voltage and a high luminous efficiency and thus has a great effect in maximizing the performance and lifetime of the full color organic light emitting diode. In particular, according to Experimental Examples 1 to 2, it was confirmed that the organic compound of the present invention can be utilized as a material of at least an electron blocking layer in a light emitting diode because the organic compound of the present invention has excellent electron blocking properties.

Although the present invention has been described based on the exemplary embodiments and examples of the present invention, the present invention is not limited to the technical ideas described in the above embodiments and examples. Those skilled in the art will appreciate that various modifications and changes may be made without departing from the scope of the present invention. However, it is apparent from the appended claims that such modifications and changes are all within the scope of the present invention.

100, 200, 300, 400, 500, 600, E: light emitting diode
110, 210, 310, 410, 510, 610:
120, 220, 320, 420, 520, 620:
130, 230, 330, 430, 530, 630:
140, 240: positive hole layer
150, 250, 332, 432, 532: Hole injection layer
160, 260, 334, 342, 434, 442, 534, and 542:
170, 270, 336, 344, 436, 444, 536, 544:
180, 280, 338, 346, 438, 446, 538, 546: electron transport layer
190, 290, 348, 448, 548: electron injection layer
266, 435, 443, 535, 543: Electron barrier layer
350, 450, 550: charge generation layer
352, 452, 552: N type charge generation layer
354, 454, 554: P type charge generation layer

Claims (14)

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

(Wherein R ₁ to R ₄ are each independently an unsubstituted or substituted C 1 to C 20 alkyl group, an unsubstituted or substituted C 1 to C 20 alkoxy group, an unsubstituted or substituted C 5 to C 30 aryl group, an unsubstituted or substituted An unsubstituted or substituted C5 to C30 heteroaryl group, an unsubstituted or substituted C5 to C30 arylalkyl group, an unsubstituted or substituted C4 to C30 heteroarylalkyl group, an unsubstituted or substituted C5 to C30 aryloxyl group, and an unsubstituted or substituted C4 to C30 At least one of R ₁ to R ₄ is a C5 to C30 aryl group or a C4 to C30 heteroaryl group having a fused aromatic ring, L ₁ to L ₆ are each a group selected from the group consisting of A, b, c, d, e and f are each independently 0 or 1, provided that at least one of them is 1, m and n are each independently a C5 to C30 arylene group or a C4 to C30 heteroarylene group; Lt; / RTI > is 0 or 1 and m + n is 1)
The method according to claim 1,
Wherein the organic compound is a compound represented by the following formula (2).
(2)

Wherein R ₅ and R ₇ are each independently an unsubstituted or substituted C 5 to C 30 aryl group, an unsubstituted or substituted C 4 to C 30 heteroaryl group, an unsubstituted or substituted C 5 to C 30 arylalkyl group, substituted C4 ~ C30 heteroaryl group, unsubstituted or substituted C5 ~ C30 aryloxy group and an unsubstituted or substituted and selected from the group consisting of substituted C4 ~ C30 heteroaryloxy group; R ₆ and R ₈ are each independently condensed (fused) C5 ~ C30 aryl group or C4 ~ C30 heteroaryl having a ring aryl group; L ₁ to _{L 6, a, b, c} , d, e, f, m, n are each as defined in formula (I) ≪ / RTI >
A first electrode;
A second electrode facing the first electrode; And
And a light emitting unit positioned between the first and second electrodes,
Wherein the light emitting unit includes a light emitting material layer, and a hole layer disposed between the first electrode and the light emitting material layer and including the organic compound according to claim 1.
The method of claim 3,
Wherein the hole layer comprises:
A hole injection layer,
And a hole transport layer disposed between the hole injection layer and the light emitting material layer and doped with a hole transporting dopant in the organic compound.
The method of claim 3,
Wherein the hole layer comprises:
A hole injection layer doped with a hole injecting dopant in the organic compound,
And a hole transport layer disposed between the hole injection layer and the light emitting material layer.
A first electrode;
A second electrode facing the first electrode; And
And a light emitting unit positioned between the first and second electrodes,
Wherein the light emitting unit comprises a light emitting material layer, and an electron blocking layer disposed between the first electrode and the light emitting material layer and including the organic compound according to claim 1.
A first electrode;
A second electrode facing the first electrode;
A first light emitting unit located between the first and second electrodes and including a first light emitting material layer;
A second light emitting unit located between the first light emitting unit and the second electrode and including a second light emitting material layer; And
A P-type charge generation layer which is located between the first and second light emitting units and contains the organic compound according to claim 1,
.
8. The method of claim 7,
The P-type charge generation layer is formed by doping the organic compound with a hole injecting dopant.
8. The method of claim 7,
And an N-type charge generation layer disposed between the P-type charge generation layer and the first light emitting unit and being an organic layer doped with an alkali metal or an alkaline earth metal.
10. The method of claim 9,
The first light emitting unit may include a hole injection layer and a first hole transporting layer disposed between the first electrode and the first light emitting material layer and a second hole transporting layer disposed between the first light emitting material layer and the N- 1 electron transport layer,
The second light emitting unit includes a second hole transporting layer disposed between the second light emitting material layer and the P-type charge generating layer, a second electron transporting layer positioned between the second light emitting material layer and the second electrode, A light emitting diode further comprising an electron injection layer.
11. The method of claim 10,
And the second hole transport layer is formed by doping the organic compound with a hole transport material.
11. The method of claim 10,
The second light emitting unit further comprises a second hole injection layer located between the second hole transport layer and the P type charge generation layer or between the P type charge generation layer and the N type charge generation layer,
And the second hole injection layer is formed by doping the organic compound with a hole injecting material.
A first electrode;
A second electrode facing the first electrode;
A first light emitting unit located between the first and second electrodes and including a first light emitting material layer;
A second light emitting unit located between the first light emitting unit and the second electrode and including a second light emitting material layer; And
And a charge generation layer located between the first and second light emitting units,
And the second light emitting unit includes an electron blocking layer disposed between the second light emitting material layer and the charge generating layer and including the organic compound according to claim 1.
A first substrate;
A driving thin film transistor located on the first substrate; And
The light emitting diode according to any one of claims 3 to 13, which is located on the first substrate and connected to the driving thin film transistor
And an organic light emitting diode (OLED) display device.

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