KR101468402B1 - Novel organic electroluminescence compounds and organic electroluminescence device containing the same - Google Patents

Abstract

The present invention relates to a novel organic electroluminescent compound and an organic electroluminescent device comprising the same. The organic electroluminescent compound according to the present invention is superior in luminous efficiency to conventional materials. In addition, the organic electroluminescent device using the organic electroluminescent compound according to the present invention as a host material for luminescence has high power efficiency, high power consumption, and high current efficiency due to low driving voltage.

Description

TECHNICAL FIELD The present invention relates to a novel organic electroluminescent compound and an organic electroluminescent device containing the same,

The present invention relates to a novel organic electroluminescent compound and an organic electroluminescent device comprising the same.

Among display devices, an electroluminescence device (EL device) is a self-luminous display device having a wide viewing angle, excellent contrast, and fast response speed. In 1987, Eastman Kodak Company first developed an organic EL device using an aromatic diamine and an aluminum complex having a low molecular weight as a material for forming a light emitting layer (Appl. Phys. Lett. 51, 913, 1987].

The most important factor for determining the luminous efficiency in the organic EL device is the luminescent material. As a luminescent material, a fluorescent luminescent material has been widely used, but the development of a phosphorescent luminescent material has been extensively studied in view of the fact that phosphorescent luminescent material can improve luminescent efficiency up to 4 times theoretically compared to a fluorescent luminescent material in the mechanism of electroluminescence . Until now, an iridium (III) complex series has been widely known as a phosphorescent material. Each RGB has bis (2- (2'-benzothienyl) -pyridinate-N, C-3 ') iridium (acetylacetonate Ir (btp) ₂ ], tris (2-phenylpyridine) iridium [Ir (ppy) ₃ ] And bis (4,6-difluorophenylpyridinate-N, C2) picolinato is iridium [Firpic] are known.

The light emitting material may be a mixture of a light emitting material (dopant) and a host material in order to improve color purity, luminous efficiency and stability. When such a light emitting material (dopant) / host material system is used, the selection is important because the host material has a great influence on the efficiency and performance of the light emitting device. In the prior art, 4,4-N, N'-dicarbazole-biphenyl (CBP) was the most widely known phosphorescent host material. In recent years, Pioneer et al. Of Japan have been using bathocuproine (BCP) and aluminum (III) bis (2-methyl-8-quinolinate) (4-phenyl phenolate) Balq) as a host material to develop a high-performance organic EL device.

However, the conventional phosphorescent host materials are advantageous from the viewpoint of luminescence characteristics, but they have the following disadvantages: (1) the material is changed when the glass transition temperature is low and the thermal stability is low and the high temperature deposition process is performed under vacuum . (2) In the organic EL device, the power efficiency is inversely proportional to the voltage since it is in the relationship of power efficiency = [(pi / voltage) x current efficiency]. However, the organic EL device using the phosphorescent host material has a higher current efficiency (cd / A) than the organic EL device using the fluorescent material, but the driving voltage is also very high, so there is no great advantage in terms of power efficiency (lm / w) . (3) In addition, when used in an organic EL device, it is unsatisfactory in terms of operating life, and luminous efficiency is still required to be improved.

On the other hand, in the organic EL device, as a hole injecting and transporting material, copper phthalocyanine (CuPc), 4,4'-bis [N- (1-naphthyl) -N- phenylamino] biphenyl (NPB) (TPD), 4,4 ', 4 "-tris (3-methylphenylphenyl) -4,4'-diamine Amino) triphenylamine (MTDATA). However, when such a material is used, there is a problem that the quantum efficiency and lifetime of the organic EL device are lowered because when the organic EL device is driven at a high current, Since the thermal stress is generated between the hole injection layers and the lifetime of the device is rapidly lowered due to the thermal stress. Further, since the organic material used for the hole injection layer has a very high hole mobility, The electron-hole charge balance is broken and the quantum efficiency (cd / A) is lowered.

Japanese Patent Application Laid-Open No. 2007-194241 or No. 2009-194042 discloses a compound in which two carbazoles are linked via an aryl, heteroaryl or fluorene group as a compound for an organic electroluminescence device. However, organic EL devices including the compounds disclosed in the above documents are still unsatisfactory in terms of power efficiency, luminous efficiency, quantum efficiency, and lifetime.

Japanese Patent Application Laid-Open No. 2007-194241 (published on August 2, 2007) Japanese Patent Application Laid-Open No. 2009-194042 (published on August 27, 2009)

Accordingly, an object of the present invention is to provide an organic electroluminescent compound having a higher luminous efficiency, higher power efficiency, and longer device life than conventional materials, and secondly, to provide a high efficiency and long-life organic electroluminescent device including the organic electroluminescent compound .

As a result of intensive studies to solve the above technical problems, the inventors of the present invention have found that when two carbazoles are linked through an aryl or heteroaryl group, an N-containing aromatic ring is bonded to the nitrogen atom of one carbazole, To achieve the above-mentioned object, thereby completing the present invention.

[Chemical Formula 1]

In Formula 1,

L ₁ is a substituted or unsubstituted (C6-C30) arylene group, or a substituted or unsubstituted (5-30 membered) heteroarylene group;

L ₂ is a single bond, a substituted or unsubstituted (C6-C30) arylene group, or a substituted or unsubstituted (5-30 membered) heteroarylene group;

Ar ₁ is a substituted or unsubstituted (C6-C30) aryl group, or a substituted or unsubstituted (5-30 membered) heteroaryl group;

A ₁ to A ₅ are each independently CR or N, provided that at least one is N;

R is hydrogen, a substituted or unsubstituted (C 1 -C 30) alkyl group, a substituted or unsubstituted (C 6 -C 30) aryl group, a substituted or unsubstituted (5-30 membered) ) Cycloalkyl group;

R ₁ to R ₄ are each independently hydrogen, deuterium, halogen, cyano, substituted or unsubstituted (C 1 -C 30) alkyl, substituted or unsubstituted (C 6 -C 30) Substituted or unsubstituted (C6-C30) cycloalkyl group, substituted or unsubstituted (C1-C30) alkoxy group, substituted or unsubstituted (C6-C30) arylsilyl group, a substituted or unsubstituted (C6-C30) aryl (C1-C30) alkylsilyl group, a substituted or unsubstituted Or unsubstituted (C1-C30) alkyl (C6-C30) arylamino group;

R ₁ to R ₄ may form a monocyclic or polycyclic alicyclic or aromatic ring connected with adjacent substituents to form a (3-30 member) carbon atom, and the carbon atom of the alicyclic or aromatic ring formed may be substituted with nitrogen, Lt; / RTI > may be replaced by one or more heteroatoms selected;

a or c is each independently an integer of 1 to 4, and when a or c is 2 or more, each R ₁ and each R ₃ may be the same or different;

b or d is independently an integer of 1 to 3, and when b or d is 2 or more, each R < _{2 >} And each R < ₄ > may be the same or different.

The organic electroluminescent compound according to the present invention is excellent in luminous efficiency, power efficiency and lifetime characteristics. In addition, the OLED device including the organic electroluminescent compound according to the present invention not only excels in luminous efficiency, but also has a low driving voltage, thereby improving power efficiency and power consumption.

The present invention will now be described in more detail, but this should not be construed as limiting the scope of the present invention.

The present invention relates to an organic electroluminescent compound represented by Formula 1, an organic electroluminescent material including the organic electroluminescent compound, and an organic electroluminescent device including the same.

The compound represented by the formula (1) of the present invention will be described in more detail as follows.

In the above formula (1), preferably,

L ₁ is a substituted or unsubstituted (C6-C30) arylene group;

L ₂ is a single bond, or a substituted or unsubstituted (C6-C30) arylene group;

Ar ₁ is a substituted or unsubstituted (C6-C30) aryl group;

R is hydrogen, a substituted or unsubstituted (C6-C30) aryl group, or a substituted or unsubstituted (5-30 membered) heteroaryl group;

R ₁ to R ₄ are each independently hydrogen, deuterium, halogen, cyano, substituted or unsubstituted (C1-C30) alkyl group or a substituted or unsubstituted (3-30 membered) monocyclic or polycyclic alicyclic group Form an aromatic ring;

a to d are each 1.

In Formula 1, more preferably,

L ₁ is a (C6-C30) arylene group unsubstituted or substituted with (C1-C6) alkyl;

L ₂ is a single bond or an unsubstituted (C6-C30) arylene group;

Ar ₁ is (C ₁ -C 6) alkyl, or a (C6-C30) aryl group unsubstituted or substituted with cyano or halogen;

R is hydrogen; (C6-C30) aryl group unsubstituted or substituted by (C1-C6) alkyl or (C1-C6) alkylsilyl; Or an unsubstituted (5-30 membered) heteroaryl group.

The formula (1) may be represented by the following formulas (1-1) to (1-4).

Formula (1-1) Formula (1-2)

Formula (1-3) Formula (1-4)

In the above formulas (1-1) to (1-4)

L ₁ , L ₂ , Ar ₁ , A ₁ to A ₅ , R ₁ to R ₄ , a, b, c and d are as defined in the formula (1).

은 피리딘, 피리미딘, 트리아진, 피라진, 피리다진 구조를 가질 수 있다.remind

May have a pyridine, pyrimidine, triazine, pyrazine, pyridazine structure.

The "(C1-C30) alkyl" described in the present invention means straight chain or branched chain alkyl having 1 to 30 carbon atoms, more preferably having 1 to 10 carbon atoms. Specific examples of the alkyl include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl and tert-butyl. The term "(C3-C30) cycloalkyl" as used herein means a monocyclic or polycyclic hydrocarbon having 3 to 30 carbon atoms, preferably 3 to 20 carbon atoms, more preferably 3 to 7 carbon atoms. Examples of the cycloalkyl include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl and the like. As used herein, the term "(C6-C30) aryl (phenylene)" means a single ring or fused ring radical derived from an aromatic hydrocarbon having 6 to 30 carbon atoms, wherein the number of carbon atoms in the ring is 6 to 15. Examples of such aryls include phenyl, biphenyl, terphenyl, naphthyl, fluorenyl, phenanthrenyl, anthracenyl, indenyl, triphenylenyl, pyrenyl, tetracenyl, perylenyl, , Fluoranthenyl, and the like. As used herein, the term "(5-30) heteroaryl (phenylene)" refers to a heteroaryl group having 5 to 30 ring skeletal atoms and one or more heteroatoms selected from the group consisting of B, N, O, S, P Quot; means an aryl group containing an atom. Here, it is preferable that the number of the ring skeleton atoms is 5 to 15. The number of heteroatoms is preferably 1 to 4, and may be a monocyclic ring system or a fused ring system condensed with at least one benzene ring, and may be partially saturated. In addition, the heteroaryl (phenylene) also includes a heteroaryl group in which at least one heteroaryl or aryl group is linked to a heteroaryl group by a single bond. Examples of such heteroaryls include furyl, thiophenyl, pyrrolyl, imidazolyl, pyrazolyl, thiazolyl, thiadiazolyl, isothiazolyl, isoxazolyl, oxazolyl, oxadiazolyl, triazinyl, tetrazinyl , Monocyclic heteroaryl such as triazolyl, tetrazolyl, furanzyl, pyridyl, pyrazinyl, pyrimidinyl and pyridazinyl, benzofuranyl, benzothiophenyl, isobenzofuranyl, dibenzofuranyl, di Benzoimidazolyl, benzothiazolyl, benzothiazolyl, benzoisothiazolyl, benzooxazolyl, isoindolyl, indolyl, indazolyl, benzothiadiazolyl, quinolyl, isoquinolyl, Fused heterocyclic heteroaryl such as norbornyl, quinazolinyl, quinoxalinyl, carbazolyl, phenoxaphyl, phenanthridinyl, benzodioxolyl and the like. As used herein, "halogen" includes F, Cl, Br, and I atoms.

Also, in the term "substituted or unsubstituted" described in the present invention, "substituted" means that a hydrogen atom is replaced by another atom or another functional group (ie, a substituent) in a certain functional group. Substituted in the general formula (I) of L _1, L _2, Ar _1, R and R ₁ to R ₄ an alkyl, substituted alkyl, substituted alkyl, silyl, substituted aryl, silyl, substituted aralkyl, silyl, substituted alkylamino, substituted arylamino, substituted alkyl (C1-C30) alkyl, halo (C1-C30) alkyl, halo (C1-C30) alkyl, halogen, cyano, carboxyl, nitro, (C3-C30) alkyl, (C2-C30) alkenyl, (C2-C30) alkynyl, (5-30 membered) heteroaryl which is unsubstituted or substituted by (C6-C30) aryl, (C6-C30) aryloxy, (C6-C30) alkylsilyl, tri (C6-C30) arylsilyl, di (C1-C30) alkyl (C6-C30) alkyl optionally substituted with (C6-C30) arylsilyl, amino, mono or di (C1-C30) alkylsilyl, (C6-C30) arylamino, (C6-C30) arylamino, (C1-C30) alkylcarbonyl, (C6-C30) arylcarbonyl, di (C6-C30) arylboronyl, di (C1-C30) alkylboronyl, (C1-C30) alkyl and (C1-C30) alkyl (C6-C30) aryl.

Representative examples of the compound according to the present invention include the following compounds.

The compounds according to the present invention can be prepared by a synthetic method known to a person skilled in the art and can be prepared, for example, according to the following reaction scheme 1.

 [Reaction Scheme 1]

In the above Reaction Scheme 1, L ₁ , L ₂ , Ar ₁ , A ₁ to A ₅ , R ₁ to R ₄ and a to d are the same as defined in the formula (1), and Hal is halogen.

In a further aspect of the present invention, the present invention provides an organic electroluminescent material comprising an organic electroluminescent compound of Formula 1 and an organic electroluminescent device comprising the above material. The material may be made of the organic electroluminescent compound of the present invention alone, and may further include common materials included in the organic electroluminescent material. An organic electroluminescent device according to the present invention includes a first electrode; A second electrode; And at least one organic material layer interposed between the first electrode and the second electrode, wherein the organic material layer contains at least one compound of the formula (1).

One of the first electrode and the second electrode may be an anode and the other may be a cathode. The organic material layer may further include one or more layers selected from the group consisting of a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, an interlayer and a hole blocking layer.

The organic electroluminescent compound of Formula 1 of the present invention may be included in the light emitting layer. When used in the light emitting layer, the organic electroluminescent compound of Formula 1 of the present invention may be included as a host material. Preferably, the light emitting layer may further include at least one dopant. If necessary, a compound other than the compound of the formula (1) of the present invention may be further included as a second host material.

The second host material may be any phosphorescent host known in the art, but is preferably selected from the group consisting of compounds represented by the following formulas (2) to (6) in view of luminous efficiency.

(2)

(3)

[Chemical Formula 4]

[Chemical Formula 5]

[Chemical Formula 6]

In the above formulas 2 to 6,

Cz has the following structure,

X is O or S,

R ₂₁ to R ₂₄ each independently represent hydrogen, deuterium, halogen, substituted or unsubstituted (C 1 -C 30) alkyl, substituted or unsubstituted (C 6 -C 30) aryl, substituted or unsubstituted (5-30 membered) R ₂₅ R ₂₆ R ₂₇ Si-; R ₂₅ to R ₂₇ are each independently substituted or unsubstituted (C 1 -C 30) alkyl, or substituted or unsubstituted (C 6 -C 30) aryl; L ₄ is a single bond, substituted or unsubstituted (C 6 -C 30) arylene, or substituted or unsubstituted (5-30 membered) heteroarylene; M is substituted or unsubstituted (C6-C30) aryl, or substituted or unsubstituted (5-30 membered) heteroaryl; Y ₁ and Y ₂ are -O-, -S-, -N (R ₃₁ ) - or -C (R ₃₂ ) (R ₃₃ ) -, and Y ₁ and Y ₂ are not simultaneously present; R ₃₁ to R ₃₃ each independently represent a substituted or unsubstituted (C1-C30) alkyl, substituted or unsubstituted (C6-C30) aryl, or a substituted or unsubstituted (5-30 W) heteroaryl, R ₃₂ and R ₃₃ may be the same or different; h and i are each independently an integer of 1 to 3; j, k, l and m are each independently an integer of 0 to 4; (Cz-L ₄ ), each (Cz), each R ₂₁ , each R ₂₂ , each R _23, or each R (s), when h, i, j, k, l or m is an integer of 2 or more. ₂₄ may be the same or different.

Specifically, preferred examples of the second host material are as follows.

As the dopant included in the organic electroluminescent device of the present invention, compounds represented by the following formulas (7) to (9) can be used.

[Chemical Formula 8] < EMI ID =

In the above formulas 7 to 9, L is selected from the following structures;

R ₁₀₀ is hydrogen, substituted or unsubstituted (C 1 -C 30) alkyl, or substituted or unsubstituted (C 3 -C 30) cycloalkyl; R ₁₀₁ to R ₁₀₉ And R ₁₁₁ To R < ₁₂₃ > are each independently hydrogen; heavy hydrogen; halogen; (C1-C30) alkyl unsubstituted or substituted with halogen; Substituted or unsubstituted (C3-C30) cycloalkyl; Cyano, or substituted or unsubstituted (C1-C30) alkoxy; R ₁₂₀ to R ₁₂₃ are adjacent substituents connected to each other to form a fused ring, for example, quinoline formation is possible; R ₁₂₄ to R ₁₂₇ are each independently hydrogen, deuterium, halogen, substituted or unsubstituted (C 1 -C 30) alkyl, or substituted or unsubstituted (C 1 -C 30) aryl; When R ₁₂₄ to R ₁₂₇ are aryl groups, the adjacent groups are connected to each other to form a fused ring, for example, fluorene formation is possible; R ₂₀₁ To R < ₂₁₁ > are each independently hydrogen, deuterium, halogen, (C1-C30) alkyl substituted or unsubstituted with halogen, or substituted or unsubstituted (C3-C30) cycloalkyl; f and g are each independently an integer of 1 to 3, and when f or g is an integer of 2 or more, each R ₁₀₀ may be the same or different from each other; n is an integer of 1 to 3;

Specific examples of the dopant material are as follows.

The present invention further provides a material for manufacturing an organic electroluminescent device in a further aspect. The material includes a compound of the present invention as a host material. When the compound of the present invention is contained as a host material, the material may further comprise a second host material, wherein the weight ratio of the first host material to the second host material is in the range of 1:99 to 99: 1.

Further, the organic electroluminescent device of the present invention includes a first electrode; A second electrode; And at least one organic material layer interposed between the first electrode and the second electrode, wherein the organic material layer includes the material for the organic electroluminescence device of the present invention.

The organic electroluminescent device of the present invention may include at least one compound selected from the group consisting of an arylamine compound and a styrylarylamine compound.

In addition, in the organic electroluminescent device of the present invention, in addition to the compound of Formula 1, an organic compound selected from the group consisting of Group 1, Group 2, Group 4, Group 5 transition metal, Lanthanide series metal and d- And the organic layer may further include a light emitting layer and a charge generating layer.

In addition, the organic electroluminescent device of the present invention may emit white light by further including at least one light emitting layer containing a blue, red or green light emitting compound known in the art, in addition to the compound of the present invention. Further, if necessary, it may further include a yellow or orange light emitting layer.

In the organic electroluminescent device of the present invention, one layer (hereinafter referred to as a "surface layer") of a chalcogenide layer, a metal halide layer and a metal oxide layer is formed on at least one inner surface of a pair of electrodes ) Or more. Concretely, it is preferable to dispose a halogenated metal layer or a metal oxide layer on the surface of the anode on the side of the light emitting medium layer and on the surface of the cathode on the side of the light emitting medium layer, with a chalcogenide (including oxide) layer of a metal of silicon and aluminum Do. Thus, stabilization of the drive can be obtained. Preferable examples of the chalcogenide include SiO _X (1? _X ? 2), AlO _x (1? _X ? 1.5), SiON or SiAlON. Preferred examples of the halogenated metal include LiF, MgF ₂ , CaF ₂ , Rare-earth metals, etc. Preferred examples of the metal oxides include Cs ₂ O, Li ₂ O, MgO, SrO, BaO, CaO and the like.

In addition, in the organic electroluminescent device of the present invention, a mixed region of the electron transfer compound and the reducing dopant or a mixed region of the hole transporting compound and the oxidizing dopant is disposed on at least one surface of the pair of electrodes thus fabricated desirable. Since the electron transfer compound is reduced to the anion by this method, it is easy to inject and transfer electrons from the mixed region to the light emitting medium. Further, since the hole transport compound is oxidized and becomes a cation, it is easy to inject and transport holes from the mixed region into the light emitting medium. Preferred oxidizing dopants include various Lewis acids and acceptor compounds, and preferred reducing dopants include alkali metals, alkali metal compounds, alkaline earth metals, rare earth metals, and mixtures thereof. Also, a white organic light emitting device having two or more light emitting layers can be manufactured using a reducing dopant layer as a charge generating layer.

The formation of each layer of the organic electroluminescent device of the present invention can be performed by a dry film formation method such as vacuum deposition, sputtering, plasma or ion plating, or a wet film formation method such as spin coating, dipping or flow coating .

In the case of the wet film formation method, a thin film is formed by dissolving or dispersing a material forming each layer in an appropriate solvent such as ethanol, chloroform, tetrahydrofuran, dioxane, etc., and any solvent may be used.

Hereinafter, the organic electroluminescent compound according to the present invention, the method for producing the same, and the luminescent characteristics of the device will be described with reference to the representative compound of the present invention for a detailed understanding of the present invention.

[Example 1] Preparation of Compound H-3

Preparation of Compound 1-1

(O) < RTI ID = 0.0 > [O- < / RTI > phenyl] -9H-carbazol-3-ylboronic acid (30 g, 104 mmol), 1- bromo- _{Pd (PPh 3) 4] (} 2.8g, 2.4mmol), Na 2 CO 3 (22g, 200mmol), toluene (400ml), ethanol (EtOH) (100ml) and H ₂ O into the (100ml) under reflux for 5 hours Lt; / RTI > Upon completion of the reaction, the reaction mixture was extracted with dichloromethane (DCM) and H ₂ O, and the DCM layer was dried with MgSO ₄ and filtered. The obtained solid was separated into a column to obtain Compound 1-1 (17.9 g, 45%).

Preparation of Compound 1-2

The compound 1-1 (17.9 g, 44.8 mmol) was dissolved in 200 ml of tetrahydrofuran (THF), cooled to -78 ^° C, 2.5M n-butyllithium (23 ml, 58.3 mmol) was slowly added thereto and stirred for 1 hour Respectively. Then, isopropyl borate (15.5 ml, 67.2 mmol) was added, the temperature was slowly raised, and the mixture was stirred at room temperature for 17 hours. Upon completion of the reaction, the reaction mixture was extracted with ethyl acetate (EA) and H ₂ O. The EA layer was dried with MgSO ₄ and the EA layer was concentrated to obtain Compound 1-2 (5.02 g, 31%).

Preparation of compounds 1-3

Compound 1-2 (5g, 13.7mmol), 3- bromo-carbazole (3.72g, 15.1mmol), Pd ( PPh 3) 4 (791mg, 0.7mmol), K 2 CO 3 (3.8g, 27.4mmol), Toluene (80 ml), EtOH (30 ml) and H ₂ O (30 ml) were added and the mixture was refluxed with stirring for 5 hours. Upon completion of the reaction, the reaction mixture was extracted with DCM and H ₂ O, and the DCM layer was dried with MgSO ₄ and filtered. The obtained solid was separated into a column to obtain Compound 1-3 (3.4 g, 53%).

Preparation of Compound H-3

(2.2g, 8.4mmol), dimethylaminopyridine (DMAP) (427mg, 3.5mmol), Compound 1-3 (3.4g, 7mmol) , K ₂ CO ₃ (2.4 g, 17.5 mmol) and dimethylformamide (DMF) (80 ml) were added, and the mixture was stirred under reflux for 3 hours. When the reaction was completed, methanol (MeOH) was added to form a solid and the resulting solid was filtered. The resulting solid was separated into a column to obtain the desired compound H-3 (2.7 g, 53%).

The compounds prepared in Example 1 above and the compounds that can be prepared by the same method are shown in Table 1 below.

[Device Embodiment 1] Fabrication of OLED element using organic electroluminescent compound according to the present invention

An OLED device having a structure using the light emitting material of the present invention was fabricated. First, a transparent electrode ITO thin film (15 OMEGA / square) obtained from a glass for OLED (manufactured by Samsung Corning) was subjected to ultrasonic cleaning using trichlorethylene, acetone, ethanol and distilled water sequentially and then stored in isopropanol Respectively. Subsequently, an ITO substrate was mounted on a substrate holder of a vacuum deposition apparatus, and N ¹ , N ^{1 '} - ([1,1'-biphenyl] -4,4'-diyl) bis ¹ - (naphthalene- ¹ -yl) -N ⁴ , N ⁴ -diphenylbenzene-1,4-diamine) was introduced into the chamber, and the chamber was evacuated until the degree of vacuum reached 10 ^-6 torr. And evaporated to deposit a 60 nm thick hole injection layer on the ITO substrate. Subsequently, N, N'-di (4-biphenyl) -N, N'-di (4-biphenyl) -4,4'- diaminobiphenyl was added to another cell in the vacuum vapor- Was evaporated to deposit a hole transport layer having a thickness of 20 nm on the hole injection layer. A hole injecting layer and a hole transporting layer were formed, and then a light emitting layer was deposited thereon as follows. Compound H-3 as a host was placed in one cell in a vacuum deposition apparatus, D-1 was added as a dopant to another cell, and the two substances were evaporated at different rates to obtain a dopant of 15 A light emitting layer with a thickness of 30 nm was deposited on the hole transporting layer by doping with an amount of 0.5 wt%. Then, on one side of the luminescent layer as an electron transporting layer was added a solution of 2- (4- (9,10-di (naphthalen-2-yl) anthracen- And lithium quinolate was added to another cell. Then, the two materials were evaporated at the same rate and doped in an amount of 50 wt%, respectively, to deposit an electron transport layer of 30 nm. Then, lithium quinolate was deposited to a thickness of 2 nm as an electron injecting layer, and then an Al cathode was deposited to a thickness of 150 nm using another vacuum vapor deposition equipment to fabricate an OLED device. Each compound was purified by vacuum sublimation under 10 ^-6 torr.

As a result, a current of 2.28 mA / cm ² flowed at 2.6 V, and green emission of 930 cd / m ² was confirmed.

[Device Embodiment 2] Fabrication of OLED device using organic electroluminescent compound according to the present invention

An OLED device was fabricated in the same manner as in Example 1 except that the host compound H-3 and the dopant compound D-102 were used as the light emitting material.

As a result, a current of 5.76 mA / cm < ² > flows at 2.7 V and green light emission of 2420 cd / m < ² >

[Device Embodiment 3] Fabrication of OLED device using organic electroluminescent compound according to the present invention

An OLED device was fabricated in the same manner as in Example 1 except that a compound H-56 was used as a host material and a dopant compound D-1 was used as a light emitting material.

As a result, a current of 3.34 mA / cm < ² > flows at 2.7 V, and green emission of 1110 cd / m < ² >

[Device Embodiment 4] Fabrication of OLED device using organic electroluminescent compound according to the present invention

 An OLED device was fabricated in the same manner as in Example 1 except that Compound H-11 was used as a host material and Compound D-1 was used as a dopant.

As a result, a current of 2.56 mA / cm < ² > flows at 2.6 V, and green light emission of 770 cd / m < ² >

[Comparative Example 1] OLED element fabrication using conventional light emitting material

A luminescent layer with a thickness of 30 nm was deposited on the hole transport layer using 4,4'-N, N'-dicarbazole-biphenyl as a host as a light emitting material and dopant compound D-86 as a host, III) Bis (2-methyl-8-quinolinato) An OLED device was prepared in the same manner as in Example 1 except that 4-phenol phenolate was deposited to a thickness of 10 nm.

As a result, a current of 8.57 mA / cm < ² > flowed at a voltage of 5.8 V, and green light emission of 3000 cd / cm ² was confirmed.

[Comparative Example 2] OLED element fabrication using conventional light emitting material

As a light emitting material, a 30 nm thick light emitting layer was deposited on the hole transport layer using 4,4'-bis (9-phenyl-9H-carbazol-3-yl) biphenyl as a host and dopant compound D-86 , An OLED device was fabricated in the same manner as in the device example 1.

As a result, a current of 11.66 mA / cm ² flowed at a voltage of 5.9 V and a green emission of 1320 cd / cm ² was confirmed.

The organic electroluminescent compounds of the present invention are superior in luminous efficiency to conventional materials. In addition, the organic electroluminescent device using the organic electroluminescent compound according to the present invention as a host material for luminescence has high power efficiency, high power consumption, and high current efficiency due to low driving voltage.

Claims (8)

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

In Formula 1,
L ₁ is a substituted or unsubstituted (C6-C30) arylene group;
L ₂ is a single bond, or a substituted or unsubstituted (C6-C30) arylene group;
Ar ₁ is a substituted or unsubstituted (C6-C30) aryl group;
A ₁ to A ₅ are each independently CR or N, provided that at least one is N;
R is hydrogen, a substituted or unsubstituted (C6-C30) aryl group, or a substituted or unsubstituted (5-30 membered) heteroaryl group;
R ₁ to R ₄ are each independently hydrogen, deuterium, halogen, cyano, or a substituted or unsubstituted (C 1 -C 30) alkyl group;
R ₁ to R ₄ may form a monocyclic or polycyclic alicyclic or aromatic ring connected with adjacent substituents to form a (3-30 member) carbon atom, and the carbon atom of the alicyclic or aromatic ring formed may be substituted with nitrogen, Lt; / RTI > may be replaced by one or more heteroatoms selected;
a to d are each 1. 2. The compound according to claim 1, wherein the substituents of substituted alkyl, substituted aryl (R) and substituted heteroaryl (R) in L ₁ , L ₂ , Ar ₁ , R and R ₁ to R ₄ independently of one another are deuterium, (C1-C30) alkyl, (C2-C30) alkenyl, (C2-C30) alkynyl, (C6-C30) alkylthio, (C3-C30) cycloalkyl, (C3-C30) cycloalkenyl, (3-7 membered) heterocycloalkyl, (C6-C30) aryl optionally substituted with (C6-C30) aryl or (5-30) heteroaryl optionally substituted with (C6-C30) aryl, (C6-C30) arylsilyl, di (C1-C30) alkyl (C6-C30) arylsilyl, (C6-C30) arylamino, (C1-C30) alkylcarbonyl, (C1-C30) alkoxycarbonyl, (C6-C30) Arylcarbonyl, di (C6- (C6-C30) aryl (C1-C30) alkyl and (C1-C30) arylcarbonyl, C30) alkyl (C6-C30) aryl. delete The method according to claim 1,
L ₁ is (C1-C6) substituted alkyl or unsubstituted (C6-C30) aryl group;
L ₂ is a single bond or an unsubstituted (C6-C30) arylene group;
Ar ₁ is a (C6-C30) aryl group which is unsubstituted or substituted by (C1-C6) alkyl, cyano or halogen;
R is hydrogen; (C6-C30) aryl group unsubstituted or substituted by (C1-C6) alkyl or (C1-C6) alkylsilyl; Or an unsubstituted (5-30 membered) heteroaryl group. The organic electroluminescent compound according to claim 1, wherein the formula (1) is represented by the following formulas (1-1) to (1-4).

Formula (1-1) Formula (1-2)

Formula (1-3) Formula (1-4)

In the above formulas (1-1) to (1-4)
L ₁ , L ₂ , Ar ₁ , A ₁ to A ₅ , R ₁ to R ₄ , a, b, c and d are as defined in claim 1. The method according to claim 1,

Is an organic electroluminescent compound having a pyridine, pyrimidine, triazine, pyrazine, pyridazine structure The organic electroluminescent compound according to claim 1, wherein the compound represented by the formula (1) is selected from the following compounds.

An organic electroluminescent device comprising the compound of claim 1.