KR20180051356A - Organic light emitting device - Google Patents

Abstract

The present invention provides an organic light emitting device. The organic light emitting device includes a positive electrode, a negative electrode facing the positive electrode, and one or more organic layers formed between the positive electrode and the negative electrode. Accordingly, the present invention can reduce a driving voltage of the organic light emitting device and improve a lifetime and efficiency of the organic light emitting device.

Description

ORGANIC LIGHT EMITTING DEVICE

The present invention relates to an organic light emitting device.

In general, organic light emission phenomenon refers to a phenomenon in which an organic material is used to convert electric energy into light energy. The organic light emitting device using the organic light emitting phenomenon has a wide viewing angle, excellent contrast, fast response time, excellent characteristics of luminance, driving voltage and response speed, and much research has been conducted.

The organic light emitting device generally has a structure including an anode and a cathode, and an organic layer between the anode and the cathode. The organic material layer may have a multilayer structure composed of different materials in order to improve the efficiency and stability of the organic light emitting device. For example, the organic material layer may include a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer. When a voltage is applied between two electrodes in the structure of such an organic light emitting device, holes are injected in the anode, electrons are injected into the organic layer in the cathode, excitons are formed when injected holes and electrons meet, When it falls back to the ground state, the light comes out.

There is a continuing need for the development of new materials for the organic materials used in such organic light emitting devices.

Korean Patent Publication No. 10-2000-0051826

The present invention provides an organic light emitting device.

The present invention relates to a positive electrode; A negative electrode opposed to the positive electrode; And at least three organic layers disposed between the anode and the cathode, the organic light emitting device comprising: a first organic layer adjacent to the anode; a second organic layer disposed on the first organic layer; Wherein the first organic layer includes a compound represented by Formula 1 and the second organic layer comprises a compound represented by Formula 2 below.

[Chemical Formula 1]

(2)

In Formula 1, R ¹ and R ² each independently represent a cyano group, a substituted or unsubstituted C6 to C60 aryl group, or a substituted or unsubstituted O, N, Si, and S A heteroaryl group having 2 to 60 carbon atoms,

R ³ and R ⁴ are each independently hydrogen, halogen, or a substituted or unsubstituted alkyl group having 1 to 40 carbon atoms,

Ar ¹ and Ar ² are each independently a substituted or unsubstituted aryl group having 6 to 60 carbon atoms or a substituted or unsubstituted heteroaryl group having 2 to 60 carbon atoms containing at least one of O, N, Si and S ego,

Wherein R ⁵ is a substituted or unsubstituted aryl group having 6 to 60 carbon atoms or a substituted or unsubstituted heteroaryl group having 2 to 60 carbon atoms containing at least one of O, N, Si and S ,

Ar ³ and Ar ⁴ each independently represent a substituted or unsubstituted aryl group having 6 to 60 carbon atoms or a heteroaryl group having 2 to 60 carbon atoms containing at least one of substituted or unsubstituted O, N, Si and S ego,

Ar ⁵ is a substituted or unsubstituted arylene group having 6 to 60 carbon atoms,

m is an integer of 0 to 5, and n is 1 or 2.

The compound represented by the formula 1 is used as a material for the hole injection layer and the compound represented by the formula 2 is used as a material for the hole transport layer or the electron blocking layer to lower the driving voltage and / Can be improved.

1 shows an example of an organic light emitting element comprising a substrate 1, an anode 2, a hole injecting layer 5, a hole transporting layer 6, a light emitting layer 7, an electron transporting layer 8 and a cathode 4 It is.

Hereinafter, the present invention will be described in detail in order to facilitate understanding of the present invention.

The present invention is characterized in that an organic material layer (first organic material layer) adjacent to an anode among the two organic material layers included between an anode and a light emitting layer contains a compound represented by the above chemical formula 1, and an organic material layer (second organic material layer) And an organic light emitting device comprising the compound represented by Formula 2 above.

In this specification the term "substituted or unsubstituted" may be substituted or means a unsubstituted by R ^a, R ^a is heavy hydrogen, a halogen, a cyano group, a nitro group, an amino group, an alkyl group having 1 to 40 carbon atoms, 1 to 40 haloalkyl groups, substituted or unsubstituted heteroalkyl groups having 1 to 40 carbon atoms containing at least one of O, N, Si and S, substituted or unsubstituted O, N, Si and S , Or an alkenyl group having 2 to 40 carbon atoms.

Halogen in this specification may be fluorine, chlorine, bromine or iodine.

In the present specification, the alkyl group having 1 to 40 carbon atoms may be a straight chain, branched chain or cyclic alkyl group. Specifically, the alkyl group having 1 to 40 carbon atoms is preferably a straight chain alkyl group having 1 to 40 carbon atoms; A straight chain alkyl group having 1 to 20 carbon atoms; A straight chain alkyl group having 1 to 10 carbon atoms; Branched or cyclic alkyl group having 3 to 40 carbon atoms; Branched or cyclic alkyl group of 3 to 20 carbon atoms; Or a branched or cyclic alkyl group having 3 to 10 carbon atoms. More specifically, the alkyl group having 1 to 40 carbon atoms is preferably a methyl group, an ethyl group, a n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a neopentyl group, a cyclohexyl group, or the like. However, the present invention is not limited thereto.

In the present specification, the heteroalkyl group having 1 to 40 carbon atoms may be one in which at least one carbon of the alkyl group is independently substituted with O, N, Si or S; Examples of the straight chain alkyl group include a n-propoxy group, a n-propoxy group, a n-propoxy group, and a heteroalkyl group substituted by Si, -Propylsilyl group, and the heteroalkyl group substituted by S is an n-propylthio group. Examples of the branched alkyl group include a heteroalkyl group in which the carbon atom of the neopentyl group is substituted by O is t-butoxy group, a heteroalkyl group substituted by N is t-butylamino group, and a heteroalkyl group substituted by Si is t Butylsilyl group, and the heteroalkyl group substituted by S is a t-butylthio group. Examples of the cyclic alkyl group include a 2-tetrahydropyranyl group in which the carbon atom of the cyclohexyl group is substituted with O is a 2-tetrahydropyranyl group, a heteroalkyl group substituted by N is a 2-piperidinyl group, The heteroalkyl group substituted by Si is a 1-sila-cyclohexyl group, and the heteroalkyl group substituted by S is a 2-tetrahydrothiopyranyl group. Specifically, the heteroalkyl group having 1 to 40 carbon atoms is preferably a straight chain, branched chain or cyclic hydroxyalkyl group having 1 to 40 carbon atoms; A linear, branched or cyclic alkoxy group having 1 to 40 carbon atoms; A linear, branched or cyclic alkoxyalkyl group having 2 to 40 carbon atoms; A straight chain, branched chain or cyclic aminoalkyl group having 1 to 40 carbon atoms; A straight chain, branched chain or cyclic alkylamino group having 1 to 40 carbon atoms; A straight chain, branched chain or cyclic alkylaminoalkyl group having 1 to 40 carbon atoms; A linear, branched or cyclic silylalkyl (oxy) group having 1 to 40 carbon atoms; A straight, branched or cyclic alkyl (oxy) silyl group having 1 to 40 carbon atoms; A straight, branched or cyclic alkyl (oxy) silylalkyl (oxy) group having 1 to 40 carbon atoms; A linear, branched or cyclic mercaptoalkyl group having 1 to 40 carbon atoms; A straight, branched or cyclic alkylthio group having 1 to 40 carbon atoms; Or a straight chain, branched chain or cyclic alkylthioalkyl group having 2 to 40 carbon atoms. More specifically, the heteroalkyl group having 1 to 40 carbon atoms is preferably a hydroxymethyl group, a methoxy group, an ethoxy group, an n-propoxy group, an iso- propoxy group, a t-butoxy group, a cycloheptoxy group, a methoxymethyl group, A 2-tetrahydropyranyl group, an aminomethyl group, a methylamino group, a n-propylamino group, a t-butylamino group, a methylaminopropyl group, a 2-piperidinyl group, a n- Butylsilyl group, a 1-sila-cyclohexyl group, a n-propylthio group, a t-butylthio group or a 2-tetrathiethylthio group. And 2-tetrahydrothiopyranyl group. However, the present invention is not limited thereto.

In the present specification, the alkenyl group having 2 to 40 carbon atoms may be a straight chain, branched chain or cyclic alkenyl group. Specifically, the alkenyl group having 2 to 40 carbon atoms is preferably a straight chain alkenyl group having 2 to 40 carbon atoms; A straight chain alkenyl group having 2 to 20 carbon atoms; A straight chain alkenyl group having 2 to 10 carbon atoms; A branched alkenyl group having 3 to 40 carbon atoms; A branched chain alkenyl group having 3 to 20 carbon atoms; A branched alkenyl group having 3 to 10 carbon atoms; A cyclic alkenyl group having 5 to 40 carbon atoms; A cyclic alkenyl group having 5 to 20 carbon atoms; Or a cyclic alkenyl group having 5 to 10 carbon atoms. More specifically, the alkenyl group having 2 to 40 carbon atoms may be an ethenyl group, a propenyl group, a butenyl group, a pentenyl group or a cyclohexenyl group. However, the present invention is not limited thereto.

In the present specification, an aryl group having 6 to 60 carbon atoms may be a monocyclic aryl group or a polycyclic aryl group. Specifically, the aryl group having 6 to 60 carbon atoms is a monocyclic or polycyclic aryl group having 6 to 30 carbon atoms; Or a monocyclic or polycyclic aryl group having 6 to 20 carbon atoms. More specifically, the aryl group having 6 to 60 carbon atoms may be a phenyl group, a biphenyl group, a terphenyl group, or the like as the monocyclic aryl group, and may be a naphthyl group, an anthracenyl group, a phenanthryl group, a triphenylenyl group, A phenyl group, a pyrenyl group, a perylenyl group, a klycenyl group or a fluorenyl group, and the like. However, the present invention is not limited thereto.

등이 될 수 있다. 다만, 이에 한정되는 것은 아니다.In the present specification, a fluorenyl group may be substituted, and two substituents may be bonded to each other to form a spiro structure. When the fluorenyl group is substituted,

And the like. However, the present invention is not limited thereto.

In the present specification, the heteroaryl group having 2 to 60 carbon atoms may be such that at least one carbon of the aryl group is each independently substituted with O, N, Si, or S. For example, the heteroaryl group in which the 9-carbon of the fluorenyl group is substituted by O is a dibenzofuranyl group, the heteroaryl group substituted by N is a carbazolyl group, the heteroaryl group substituted by Si is a 9-sila-fluorenyl group , The heteroaryl group substituted with S is a dibenzothiophenyl group. Specifically, the heteroaryl group having 2 to 60 carbon atoms is a heteroaryl group having 2 to 30 carbon atoms; Or a heteroaryl group having 2 to 20 carbon atoms. More specifically, the heteroaryl group having 2 to 60 carbon atoms is preferably a thiophene group, a furane group, a furyl group, an imidazole group, a thiazole group, an oxazole group, an oxadiazole group, a triazole group, a pyridyl group, a bipyridyl group, A pyridazinyl group, a pyridazinyl group, a pyrazinyl group, a pyrazinyl group, a pyrazinyl group, a pyrazinyl group, a pyrazinyl group, a pyrazinyl group, a quinolizinyl group, a quinoxalinyl group, a phthalazinyl group, a pyridopyrimidinyl group, A benzofuranyl group, a phenanthroline group, an isoquinoline group, an indole group, a carbazole group, a benzoxazole group, a benzoimidazole group, a benzothiazole group, a benzocarbazole group, a benzothiophene group, An oxazolyl group, a thiadiazolyl group, a phenothiazinyl group, and a dibenzofuranyl group, but are not limited thereto.

As used herein, the arylene group means a divalent organic group in which any hydrogen radical of any of the above-mentioned aryl groups is removed.

Wherein R ¹ and R ² are each independently a cyano group; An aryl group having 6 to 20 carbon atoms and substituted with at least one member selected from the group consisting of halogen and cyano; Or a heteroaryl group having 2 to 20 carbon atoms containing at least one of O, N, Si and S substituted with at least one substituent selected from the group consisting of halogens and cyano groups.

More specifically, in Formula 1, R ¹ and R ² are each independently a cyano group, a 2,3,4,5,6-pentafluorophenyl group, a 2,3,5,6-tetrafluoro-4-cyano Naphthyl group or a 2,3,5,6-tetrafluoropyridin-4-yl group.

In Formula 1, R ³ and R ⁴ may each independently be hydrogen, halogen, or an alkyl group having 1 to 10 carbon atoms substituted with halogen.

More specifically, R ³ and R ⁴ in Formula 1 may each independently be hydrogen, fluorine or trifluoromethyl.

Wherein Ar ¹ and Ar ² are each independently at least one substituent selected from the group consisting of a halogen, a cyano group, an alkyl group having 1 to 40 carbon atoms, a haloalkyl group having 1 to 40 carbon atoms, and a haloalkoxy group having 1 to 40 carbon atoms A substituted or unsubstituted aryl group having 6 to 60 carbon atoms; N, Si and S substituted or unsubstituted with at least one substituent selected from the group consisting of a halogen, a cyano group, an alkyl group having 1 to 40 carbon atoms, a haloalkyl group having 1 to 40 carbon atoms, and a haloalkoxy group having 1 to 40 carbon atoms Or a heteroaryl group having 2 to 60 carbon atoms including at least one of R < 1 >

More specifically, in Formula 1, Ar ¹ and Ar ² are each independently a phenyl group, a naphthyl group, a quinazolinyl group, a thiophenyl group, or a pyridinyl group, or at least one hydrogen of these is -F, -CN , it may be one substituted with _{-CH 3, -CF 3, -OCF 3} , -OCHF 2, -OCH 2 F 3 and -OCH (CF _{3) 2} or more substituents, selected from the group consisting of.

The compound represented by Formula 1 may be selected from the group consisting of the following compounds.

In the above formula (2), the square bracket '[]' means that Ar ⁵ can bond to any carbon of the carbon atoms 1 to 10 of phenanthrene. When m in the general formula (2) is an integer of 1 or more, at least one R ⁵ may also be bonded to any one of carbon 1 to 10 of phenanthrene.

Specifically, when m in Formula 2 is 0 and n is 1, when Ar ⁵ is bonded to any one of carbon 1 to 8 of phenanthrene, Formula 2 is as shown in Formula 2-1, Ar ⁵ is bonded to any one of carbons 9 and 10 of phenanthrene, Formula 2 is as shown in Formula 2-2 below.

[Formula 2-1] [Formula 2-2]

In Formulas (2-1) and (2-2), Ar ³ to Ar ⁵ are as defined in Formula (2).

When n in the above formula (2) is 2, each of Ar ³ , Ar ⁴ and Ar ⁵ in two -Ar ⁵ -NAr ³ Ar ⁴ groups bonded to phenanthrene may be the same or different from each other.

In order to exhibit better voltage characteristics and lifetime characteristics in combination with the compound represented by Formula 1, n in Formula 2 may be 1.

In Formula 2, Ar ³ and Ar ⁴ each independently represent an aryl group having 6 to 30 carbon atoms, which is substituted or unsubstituted with an alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted alkyl group having 2 to 30 carbon atoms substituted with an alkyl group having 1 to 10 carbon atoms Lt; / RTI > heteroaryl group.

More specifically, in Formula 2, Ar ³ and Ar ⁴ are each independently selected from the group consisting of benzene, biphenyl, terphenyl, naphthalene, phenanthrene, triphenylene, phenylnaphthalene, 9,9-dimethylfluorene, A monovalent residue derived from arene or heteroarene selected from the group consisting of phenylfluorene, spiro [fluorene-9,9'-fluorene], dibenzofuran and dibenzothiophene.

In Formula 2, Ar ⁵ may be a divalent residue derived from benzene, biphenyl or 9,9-dimethylfluorene.

In Formula 2, if m is an integer of 1 to 5, phenanthrene is substituted with at least one R ⁵ . And when m is 0, phenanthrene is unsubstituted as R ⁵ .

The R ⁵ may be a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms. More specifically, R < ⁵ > is selected from the group consisting of benzene, biphenyl, terphenyl, naphthalene, phenanthrene, triphenylene, t-butylbenzene, cyanobenzene, 9,9-dimethylfluorene, , Spiro [fluorene-9,9'-fluorene, dibenzofuran, and dibenzothiophene.

The compound represented by Formula 2 may be a compound represented by Formula 2-3.

[Formula 2-3]

In Formula 2-3,

Ar ³ to Ar ⁵ have the same definitions as in the above formula (2)

R ⁶ is hydrogen, a substituted or unsubstituted aryl group having 6 to 60 carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 60 carbon atoms containing at least one of O, N, Si and S.

When R ⁶ is not hydrogen, it is defined as R ^{5 in the} above formula (2), and the specific types of R ⁵ have been described above, and a detailed description thereof will be omitted.

The compound represented by Formula 2 may be selected from the group consisting of the following compounds.

The organic light emitting device of the present invention includes: a cathode; A negative electrode opposed to the positive electrode; And three or more organic layers disposed between the anode and the cathode.

The organic light emitting device according to the present invention may be a normal type organic light emitting device in which an anode, three or more organic layers, and a cathode are sequentially stacked on a substrate. In addition, the organic light emitting device according to the present invention may be an inverted type organic light emitting device in which an anode, three or more organic layers and an anode are sequentially stacked on a substrate.

The three or more organic layers form a laminated multilayer structure. The three or more organic layers include a light emitting layer and at least two organic layers between the anode and the light emitting layer.

Specifically, as shown in FIG. 1, the three or more organic material layers include a hole injection layer 5 adjacent to the anode 2; A hole transport layer 6 provided on the hole injection layer 5; An electron blocking layer (not shown in FIG. 1) provided on the hole transport layer 6; A light emitting layer (7) provided on the electron blocking layer; And an electron injection layer (not shown in FIG. 1), an electron transport layer 8, or an electron injection and transport layer (not shown in FIG. 1) provided on the light emitting layer 7. However, the structure of the organic light emitting device is not limited thereto, and may include a smaller number of organic layers.

In this specification, the hole injection layer means an organic material layer in contact with the anode of the organic light emitting device, and a hole injected from the anode to transfer the hole to another organic material layer. Accordingly, the hole injection layer may be referred to as a charge generation layer. The electron blocking layer means a layer which inhibits electrons transferred from the light emitting layer from being transmitted to the anode. Accordingly, the electron blocking layer may also be referred to as an electron blocking layer or an electron blocking layer.

The organic electroluminescent device according to the present invention comprises a compound represented by the formula (1) in an organic material layer (first organic material layer) adjacent to an anode among two organic material layers provided between an anode and a light emitting layer, Can be produced by materials and methods known in the art except that the organic layer (second organic layer) includes the compound represented by the above formula (2). In addition, the plurality of organic layers may be formed of the same material or different materials.

For example, the organic light emitting device according to the present invention may include one of an anode and a cathode on a substrate; An organic layer; And the other one of the positive electrode and the negative electrode is sequentially laminated. At this time, a metal or a metal oxide having conductivity or an alloy thereof is deposited on the substrate using a PVD (physical vapor deposition) method such as sputtering or e-beam evaporation to form an anode Forming an organic material layer including a hole injecting layer, a hole transporting layer, an electron blocking layer, a light emitting layer, and an electron injecting and transporting layer on the hole transporting layer, and then depositing a material usable as a cathode thereon. In addition to such a method, an organic light emitting device can be manufactured by sequentially depositing a cathode material, an organic material layer, and a cathode material on a substrate (WO 2003/012890). However, the manufacturing method is not limited thereto.

The compound represented by the formula (1) and the compound represented by the formula (2) may be formed into an organic layer by a solution coating method as well as a vacuum deposition method in the production of an organic light emitting device. Here, the solution coating method refers to spin coating, dip coating, doctor blading, inkjet printing, screen printing, spraying, roll coating and the like, but is not limited thereto.

As the anode material, a material having a large work function is preferably used so that hole injection can be smoothly conducted to the organic material layer. Specific examples of the positive electrode material include metals such as vanadium, chromium, copper, zinc, and gold, or alloys thereof; Metal oxides such as zinc oxide, indium oxide, indium tin oxide (ITO), and indium zinc oxide (IZO); ZnO: Al or SNO _2: a combination of a metal and an oxide such as Sb; Conductive polymers such as poly (3-methylthiophene), poly [3,4- (ethylene-1,2-dioxy) thiophene] (PEDOT), polypyrrole and polyaniline.

The negative electrode material is preferably a material having a small work function to facilitate electron injection into the organic material layer. Specific examples of the negative electrode material include metals such as magnesium, calcium, sodium, potassium, titanium, indium, yttrium, lithium, gadolinium, aluminum, silver, tin and lead or alloys thereof; Layer structure materials such as LiF / Al or LiO ₂ / Al, but are not limited thereto.

On the anode, a hole injecting layer may be provided as a hole injecting hole from the anode. The hole injection layer may include a compound represented by Formula 1 as a first organic material layer that is included between the anode and the light emitting layer and is adjacent to the anode. Since the specific structure of the compound represented by the formula (1) has been described above, a detailed description thereof will be omitted here.

As a conventional hole transporting material, aromatic diamine derivatives and aromatic condensed ring diamine derivatives are mainly used. When such a hole transporting material is used, there is a problem that power consumption is increased and device lifetime is lowered because a high applied voltage is required. In order to solve such a problem, a method has been proposed in which an electron-accepting compound such as Lewis acid is doped in a hole injection layer or used alone as a hole injection material. As such an electron-accepting compound, a compound represented by the following formula (P1) has been proposed.

[Formula (P1)

However, the known electron-accepting compounds have another problem of degrading the lifetime of the organic light emitting device due to poor thermal stability by contaminating the deposition equipment due to their sublimation properties.

On the other hand, the compound represented by the formula (1) exhibits excellent solubility in an organic solvent and can be provided in a high purity, and the molecular stereostructure of an existing electron-accepting compound is changed to cause crystallization , Excellent in thermal stability and high in electron acceptance. Accordingly, when the compound represented by Formula 1 is used as a hole injecting material, a stable interface with the electrode can be formed, and a low driving voltage and long life can be realized.

In addition, the hole injection layer may further include a hole injection material known in the art, in addition to the compound of Formula 1. As such a hole injecting material, it is preferable that HOMO (highest occupied molecular orbital) be between the work function of the cathode material and the HOMO of the surrounding organic layer. Specific examples of such hole injecting materials include metal porphyrin, oligothiophene, arylamine-based organic materials, hexanitrile hexaazatriphenylene-based organic materials, quinacridone-based organic materials, perylene- Based organic materials, anthraquinone, and polyaniline and polythiophene-based conductive polymers, but are not limited thereto.

On the hole injection layer, a hole transport layer may be provided as a layer that receives holes from the hole injection layer and transports holes to the light emission layer. When the second organic material layer is a hole transporting layer, the compound represented by Formula 2 is used as a material for forming the hole transporting layer. Since the compound represented by the above-described formula (2) has been described in detail in the foregoing, detailed description is omitted here.

The compound represented by Formula 2 is suitable for transporting holes from the anode or the hole injection layer to the light emitting layer because of its high mobility to holes.

In addition, the hole transport layer may further include a hole transport material known in the art to which the present invention belongs, in addition to the compound represented by the general formula (2). Specific examples of such a hole transporting material include an arylamine-based organic material, a conductive polymer, and a block copolymer having a conjugated portion and a non-conjugated portion together, but the present invention is not limited thereto.

An electron blocking layer may be formed on the hole transport layer to prevent electrons transferred to the light emitting layer from moving toward the anode. When the second organic material layer is an electron blocking layer, the electron blocking layer may be formed of a compound represented by the formula (2). In particular, when the electron blocking layer is formed of the compound represented by Formula 2, the driving voltage of the organic light emitting device can be lowered, and the light emitting efficiency and lifetime can be improved.

On the other hand, the second organic material layer may be a hole transporting layer or an electron blocking layer, or a hole transporting layer and an electron blocking layer. Accordingly, the hole transporting layer and / or the electron blocking layer may be formed of a compound represented by Formula 2, and may include other organic materials known to those skilled in the art. If the second organic material layer is a hole transporting layer, the electron blocking layer is made of another organic material known in the art to which the present invention belongs. If the second organic material layer is an electron blocking layer, And may be made of other organic materials.

The light emitting layer is a layer capable of emitting light in a visible light region by transporting and combining holes and electrons from the hole transporting layer and the electron transporting layer, respectively, and the light emitting layer may include a host material and a dopant material.

The host material includes a condensed aromatic ring derivative or a heterocyclic compound. Specific examples of the condensed aromatic ring derivatives include anthracene derivatives, pyrene derivatives, naphthalene derivatives, pentacene derivatives, phenanthrene compounds, and fluoranthene compounds. Examples of the heterocycle-containing compounds include carbazole derivatives, dibenzofuran derivatives, Furan compounds, pyrimidine derivatives, and the like, but are not limited thereto.

Examples of the dopant material include aromatic amine derivatives, styrylamine compounds, boron complexes, fluoranthene compounds, and metal complexes. Specific examples of the aromatic amine derivatives include condensed aromatic ring derivatives having substituted or unsubstituted arylamino groups, and examples thereof include pyrene, anthracene, chrysene, and peripherrhene having an arylamino group. Examples of the styrylamine compound include substituted or unsubstituted Wherein at least one aryl vinyl group is substituted with at least one aryl vinyl group, and at least one substituent selected from the group consisting of an aryl group, a silyl group, an alkyl group, a cycloalkyl group and an arylamino group is substituted or unsubstituted. Specific examples thereof include, but are not limited to, styrylamine, styryldiamine, styryltriamine, styryltetraamine, and the like. Examples of the metal complex include iridium complex, platinum complex, and the like, but are not limited thereto.

An electron transport layer and an electron injection layer may be provided on the light emitting layer. An electron injecting and transporting layer may be formed on the light emitting layer to simultaneously perform electron injecting and transporting functions.

The electron transporting layer is a layer that receives electrons from the electron injecting layer and transports electrons to the light emitting layer. The electron transporting material is a material capable of transferring electrons from the cathode well to the light emitting layer. Do. Specific examples include an Al complex of 8-hydroxyquinoline; Complexes containing Alq ₃ ; Organic radical compounds; Hydroxyflavone-metal complexes, and the like, but are not limited thereto. The electron transporting layer can be used with any desired cathode material as used according to the prior art. In particular, an example of a suitable cathode material is a conventional material having a low work function followed by an aluminum layer or a silver layer. Specifically cesium, barium, calcium, ytterbium and samarium, in each case followed by an aluminum layer or a silver layer.

The electron injection layer is a layer for injecting electrons from the electrode. The electron injection layer has an ability to transport electrons, has an electron injection effect from the cathode, and has an excellent electron injection effect with respect to the light emitting layer or the light emitting material. A compound which prevents migration to a layer and is excellent in a thin film forming ability is preferable. Specific examples thereof include fluorenone, anthraquinodimethane, diphenoquinone, thiopyran dioxide, oxazole, oxadiazole, triazole, imidazole, perylenetetracarboxylic acid, preorenylidene methane, A nitrogen-containing 5-membered ring derivative, and the like, but are not limited thereto.

Examples of the metal complex compound include 8-hydroxyquinolinato lithium, bis (8-hydroxyquinolinato) zinc, bis (8-hydroxyquinolinato) copper, bis (8- Tris (8-hydroxyquinolinato) aluminum, tris (2-methyl-8-hydroxyquinolinato) aluminum, tris (8- hydroxyquinolinato) gallium, bis (10- Quinolinato) beryllium, bis (10-hydroxybenzo [h] quinolinato) zinc, bis (2-methyl-8- quinolinato) chlorogallium, bis (2-methyl-8-quinolinato) (2-naphtholato) gallium, and the like, But is not limited thereto.

The organic light emitting device according to the present invention may be a front emission type, a back emission type, or a both-sided emission type, depending on the material used.

The production of the above-described organic light-emitting device will be specifically described in the following examples. However, the following examples are intended to illustrate the present invention, and the scope of the present invention is not limited thereto.

Example  1: Fabrication of organic light emitting device

A glass substrate coated with ITO (indium tin oxide) having a thickness of 1000 Å was immersed in distilled water containing detergent and washed with ultrasonic waves. At this time, Fischer Co. product was used as a detergent, and distilled water filtered by a secondary filter using a filter of Millipore Co. was used as distilled water. The ITO substrate was washed for 30 minutes and then washed twice with distilled water and ultrasonically cleaned for 10 minutes. After the distilled water was washed, the ITO substrate was ultrasonically washed with a solvent of isopropyl alcohol, acetone, and methanol, dried, and then transported to a plasma cleaner. Then, the ITO substrate was cleaned using oxygen plasma for 5 minutes, and then transported by a vacuum evaporator.

On the prepared ITO electrode, the following compound 1-1 was thermally vacuum-deposited to a thickness of 50 Å to form a hole injection layer. The following compound HT-1 was vacuum-deposited on the hole injection layer to a thickness of 1250 Å to form a hole transport layer. Subsequently, the following compound 2-1 was vacuum deposited on the hole transport layer to a thickness of 150 Å to form an electron blocking layer. The following compound BH and the following compound BD were vacuum deposited on the electron blocking layer at a weight ratio of 25: 1 to form a light emitting layer with a thickness of 200 ANGSTROM. The following compound ET-1 and LiQ (Lithium Quinolate) were vapor deposited on the light emitting layer at a weight ratio of 1: 1 to form an electron injection and transport layer having a thickness of 360 Å. Lithium fluoride (LiF) 12 Å thick and aluminum 2000 Å thick were sequentially deposited on the electron injection and transport layer to form a cathode.

In the above process, the deposition rate of the organic material was maintained at 0.4 to 0.7 Å / sec, the deposition rate of the lithium fluoride of the cathode was 0.3 Å / sec and the deposition rate of aluminum was maintained at 2 Å / sec. ^-7 to 5 X 10 < ^-6 > torr to produce an organic light emitting device.

Example  2 to 7 and Comparative Example  1 to 16: Preparation of organic light emitting device

An organic light emitting device was fabricated in the same manner as in Example 1 except that the compound for forming the hole injection layer and / or the electron blocking layer was changed as shown in Table 1 below.

Test Example : Performance evaluation of organic light emitting device

The voltage, efficiency and lifetime of the organic light emitting device fabricated according to Examples 1 to 7 and Comparative Examples 1 to 16 were measured at a current density of 10 mA / cm ² , and the results are shown in Table 1. The lifetime T95 is defined as the time required to reduce to 95% of the initial luminance (3000 nits) and was measured at a current density of 20 mA / cm ² .

Hole injection layer Electronic stop layer Voltage (V) Current efficiency (cd / A) T95 (hr) Comparative Example 1 HAT EB-1 5.11 4.89 270 Comparative Example 2 1-1 EB-1 4.82 5.06 285 Comparative Example 3 1-2 EB-1 4.85 5.11 290 Comparative Example 4 1-3 EB-1 4.81 5.00 280 Comparative Example 5 1-4 EB-1 4.92 5.13 285 Comparative Example 6 1-5 EB-1 4.85 5.05 290 Comparative Example 7 1-6 EB-1 4.94 5.07 285 Comparative Example 8 1-7 EB-1 4.85 5.18 285 Comparative Example 9 1-8 EB-1 4.87 5.16 290 Comparative Example 10 HAT 2-1 4.82 5.25 305 Comparative Example 11 HAT 2-2 4.81 5.30 320 Comparative Example 12 HAT 2-3 4.83 5.29 315 Comparative Example 13 HAT 2-4 4.79 5.31 305 Comparative Example 14 HAT 2-5 4.82 5.25 305 Comparative Example 15 HAT 2-7 4.78 5.37 320 Comparative Example 16 HAT 2-8 4.77 5.38 315 Example 1 1-1 2-1 4.55 5.53 335 Example 2 1-2 2-2 4.57 5.52 335 Example 3 1-3 2-3 4.58 5.52 330 Example 4 1-4 2-4 4.52 5.56 330 Example 5 1-5 2-5 4.61 5.47 345 Example 6 1-6 2-7 4.62 5.46 340 Example 7 1-7 2-8 4.61 5.47 345

In Table 1, the organic light emitting device using the existing compound (Comparative Example 1) and the compound represented by Formula 1 as the hole injection layer are used, but the organic light emitting device using the existing compound as the electron blocking layer material (Examples 2 to 9) and the compound represented by Chemical Formula 2 as the electron blocking layer material, but the organic light emitting devices using the existing compounds as the hole injection layer material (Comparative Examples 10 to 16) are shown.

Comparing the examples and the comparative examples, it was found that when the compounds represented by the above formulas (1) and (2) were used as the materials of the electron injecting layer and electron blocking layer (Examples 1 to 7) (Comparative Examples 2 to 16) in combination with a compound represented by the above formula (2) or a compound represented by the above formula (2) in combination with a conventional compound (Comparative Examples 2 to 16).

Thus, it is confirmed that the organic light emitting device of the present invention exhibits a low driving voltage and an improved efficiency and a long lifetime through the combination of the compounds represented by the formulas (1) and (2).

1: substrate
2: anode
4: cathode
5: Hole injection layer
6: hole transport layer
7:
8: Electron transport layer

Claims (10)

anode; A negative electrode opposed to the positive electrode; And at least three organic layers disposed between the anode and the cathode,
A first organic material layer adjacent to the anode, a second organic material layer provided on the first organic material layer, and a light emitting layer provided on the second organic material layer,
Wherein the first organic material layer comprises a compound represented by the following general formula (1)
Wherein the second organic layer comprises a compound represented by Formula 2:
[Chemical Formula 1]

(2)

In Formula 1, R ¹ and R ² each independently represent a cyano group, a substituted or unsubstituted C6 to C60 aryl group, or a substituted or unsubstituted O, N, Si, and S A heteroaryl group having 2 to 60 carbon atoms,
R ³ and R ⁴ are each independently hydrogen, halogen, or a substituted or unsubstituted alkyl group having 1 to 40 carbon atoms,
Ar ¹ and Ar ² are each independently a substituted or unsubstituted aryl group having 6 to 60 carbon atoms or a substituted or unsubstituted heteroaryl group having 2 to 60 carbon atoms containing at least one of O, N, Si and S ego,
Wherein R ⁵ is a substituted or unsubstituted aryl group having 6 to 60 carbon atoms or a substituted or unsubstituted heteroaryl group having 2 to 60 carbon atoms containing at least one of O, N, Si and S ,
Ar ³ and Ar ⁴ each independently represent a substituted or unsubstituted aryl group having 6 to 60 carbon atoms or a heteroaryl group having 2 to 60 carbon atoms containing at least one of substituted or unsubstituted O, N, Si and S ego,
Ar ⁵ is a substituted or unsubstituted arylene group having 6 to 60 carbon atoms,
m is an integer of 0 to 5, and n is 1 or 2.
The compound according to claim 1, wherein R ¹ and R ² are each independently a cyano group; An aryl group having 6 to 20 carbon atoms and substituted with at least one member selected from the group consisting of halogen and cyano; Or a heteroaryl group having 2 to 20 carbon atoms and containing at least one of O, N, Si and S substituted with at least one substituent selected from the group consisting of halogens and cyano groups.
The organic light-emitting device according to claim 1, wherein R ³ and R ⁴ are each independently hydrogen, halogen, or an alkyl group having 1 to 10 carbon atoms substituted with halogen.
The compound according to Claim 1, wherein Ar ¹ and Ar ² are each independently selected from the group consisting of a halogen, a cyano group, an alkyl group having 1 to 40 carbon atoms, a haloalkyl group having 1 to 40 carbon atoms, and a haloalkoxy group having 1 to 40 carbon atoms An aryl group having 6 to 60 carbon atoms, which is substituted or unsubstituted with a substituent; N, Si and S substituted or unsubstituted with at least one substituent selected from the group consisting of a halogen, a cyano group, an alkyl group having 1 to 40 carbon atoms, a haloalkyl group having 1 to 40 carbon atoms, and a haloalkoxy group having 1 to 40 carbon atoms ≪ / RTI > is a heteroaryl group having 2 to 60 carbon atoms containing at least one heteroatom group.
The compound according to claim 1, wherein Ar ³ and Ar ⁴ each independently represent an aryl group having 6 to 30 carbon atoms, which is substituted or unsubstituted with an alkyl group having 1 to 10 carbon atoms, or an aryl group having 2 to 30 carbon atoms substituted or unsubstituted with an alkyl group having 1 to 10 carbon atoms ≪ / RTI > to < RTI ID = 0.0 > 30. ≪ / RTI >
The organic electroluminescent device according to claim 1, wherein Ar ⁵ is a divalent residue derived from benzene, biphenyl or 9,9-dimethylfluorene.
The organic electroluminescent device according to claim 1, wherein the compound represented by Formula 2 is a compound represented by Formula 2-3.
[Formula 2-3]

In Formula 2-3,
Ar ³ to Ar ⁵ have the same definitions as in the above formula (2)
R ⁶ is hydrogen, a substituted or unsubstituted aryl group having 6 to 60 carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 60 carbon atoms containing at least one of O, N, Si and S.
The organic electroluminescent device according to claim 1, wherein the compound represented by the formula (1) is selected from the group consisting of the following compounds:

.
2. The organic electroluminescent device according to claim 1, wherein the compound represented by Formula 2 is selected from the group consisting of the following compounds:

.

The organic electroluminescent device according to claim 1, wherein the three or more organic layers include a hole injection layer adjacent to the anode, A hole transport layer provided on the hole injection layer; An electron blocking layer provided on the hole transporting layer; A light emitting layer provided on the electron blocking layer; And an electron injection layer, an electron transport layer, or an electron injection and transport layer provided on the light emitting layer,
Wherein the hole injection layer comprises the compound represented by Formula 1,
Wherein the hole transporting layer and / or the electron blocking layer comprises a compound represented by the general formula (2).

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