KR100471365B1 - Blue color emitting compounds for organic electroluminescent device and organic electroluminescent device using them - Google Patents

Abstract

The present invention relates to a blue light emitting compound for an organic electroluminescent device and an organic electroluminescent device using the same, and a blue for an organic electroluminescent device represented by the following Chemical Formulas 1 to 3 in which triple bonds having less conjugation effect than double bonds are introduced. By providing an organic light emitting device using the light emitting compound and at the same time it can emit light of a shorter wavelength than the existing blue material, it is possible to provide an organic electroluminescent device with high light stability and quantum efficiency.

In the above formulas, Y ₁ to Y ₆ and X ₁ to X ₃ are as defined in the specification.

Description

Blue light emitting compounds for organic electroluminescent device and organic electroluminescent device using them}

The present invention relates to a blue light emitting compound for organic electroluminescent devices, and more particularly to a blue light emitting compound for organic electroluminescent devices represented by the following Chemical Formulas 1 to 3 in which triple bonds having less conjugation effect than double bonds are introduced.

The present invention also relates to an organic electroluminescent device containing the following blue light emitting compound, and more particularly to an organic electroluminescent device in which an organic thin film layer including a light emitting region is provided between a first electrode (anode) and a second electrode (cathode). The organic electroluminescent device according to claim 1, wherein at least one layer of the constituent layers of the organic thin film layer contains at least one compound represented by the following general formulas (1) to (3).

[Formula 1]

[Formula 2]

[Formula 3]

In the above formulas, Y ₁ to Y ₆ and X ₁ to X ₃ are as defined below.

Recently, as the development of the information and communication industry is accelerated, higher performance is required in the field of display devices, which is one of the most important fields. Such displays can be divided into luminescent and non-luminescent. Cathode Ray Tube (CRT), Electroluminescence Display (ELD), Light Emitting Diode (LED), Plasma Display Panel (PDP), etc. have. Non-light emitting displays include liquid crystal displays (LCDs).

The light emitting and non-light emitting displays have basic performances such as operating voltage, power consumption, brightness, that is, brightness, contrast, response speed, lifetime, and display liquid. However, among these, liquid crystal displays, which are widely used to date, have problems in response speed, contrast, and visual dependence among the above basic performances. In this situation, the display using the light emitting diode has a fast response time and is self-luminous so that no back light is required, and the luminance is excellent, and it has various advantages, thus complementing the problems of the liquid crystal display. It is expected to take place as an element.

The light emitting diode is mainly difficult to apply to a large area electroluminescent device because an inorganic material having a crystalline form is used. In addition, in the case of an electroluminescent device using an inorganic material, a driving voltage is required to be 200 V or more, and a price is also disadvantageous. However, since 1987, when Eastman Kodak published a device made of a material having a π-conjugated structure called alumina quinone, research into electroluminescent devices using organic materials has been actively conducted.

Electroluminescence devices (EL devices) are classified into inorganic electroluminescent devices and organic electroluminescent devices according to materials for forming an emitter layer.

The organic electroluminescent device is a self-luminous device that electrically excites fluorescent organic compounds to emit light, and has an advantage of excellent luminance, driving voltage, and response speed, and multicoloring, compared to inorganic electroluminescent devices.

In addition, this element is a conductor element that emits light at low voltage direct current application of several volts, and has excellent characteristics such as high brightness, high speed response, wide viewing angle, surface emission, and thin color emission.

Organic electroluminescent devices have characteristics not found in other displays, and thus, they are expected to be used in full-color flat panel displays.

In 1987, C. W. Tang et al. Reported the practical device performance in organic electroluminescent devices (Applied Physics Letters, Vol. 51, No. 12, pages 913-915 (1987)). Here, they devised a structure in which a thin film (hole transporting layer) obtained from a diamine derivative and a thin film (electron transporting light emitting layer) obtained from tri (8-quinolinolato) aluminum (hereinafter abbreviated as Alq3) were laminated as an organic layer. By using such a laminated structure, it is possible to lower the barrier of injection of electrons and holes from the electrode to the organic layer, and to increase the recombination probability of electrons and holes in the organic layer.

Subsequently, C. Adachi et al. Obtained the three-layer structure of the hole transporting layer, the light emitting layer, and the electron transporting layer (Japanese Journal of Applied Physics, Vol. By devising an organic electroluminescent device having an organic layer of the structure (Applied Physics Letter No. 55, 15, 1489-1491 (1989)) and constructing a multilayer structure suitable for materials and combinations thereof, the device characteristics can be optimized. Indicated.

The organic electroluminescent element may be composed of a first electrode (anode), a second electrode (cathode), and an organic light emitting medium. The organic light emitting medium includes at least two separate organic layers, one layer for injecting and transporting electrons and one layer for forming a region for injecting and transporting holes in the device, and in addition, a multilayer of a thin organic film. This may be further included. The layer for injecting and transporting electrons and the layer for injecting and transporting holes may be divided into an electron injection layer, an electron transport layer, a hole injection layer, and a hole transport layer, respectively. In addition, the organic light emitting medium may further include a light emitting layer in addition to the electron injection and transport layer and the hole injection and transport layer.

The organic EL device having a simple structure may be composed of a first electrode / charge transport layer and a light emitting layer / second electrode. In addition, the organic electroluminescent device may be configured by separating each organic functional layer from the first electrode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / electron injection layer / second electrode.

The driving principle of the organic EL device having the structure as described above is as follows.

When a voltage is applied between the anode and the cathode, holes (holes) injected from the anode are moved to the light emitting layer via the hole transport layer. On the other hand, electrons are injected into the light emitting layer from the cathode via the electron transport layer, and carriers are recombined in the light emitting layer to generate excitons. The excitons change from the excited state to the ground state, whereby the fluorescent molecules in the light emitting layer emit light to form an image.

A manufacturing process of a general organic EL device is as follows (see FIG. 1).

First, a first electrode (anode) material is formed on a transparent substrate such as glass. In this case, ITO (Indium tin oxide, In ₂ O ₃ + SnO ₂ ) is mainly used as the cathode material.

A hole injection layer (HIL) is formed on the anode material. Copper phthalocyanine (CuPC: Copper (II) Phthalocyanine) is mainly used as the hole injection layer, and its thickness is about 10 to 30 nm.

Next, a hole transport layer (HTL) is introduced. The hole transport layer is formed by depositing NPD (N, N-di (naphthalen-1-yl) -N, N'-diphenylbenzidine) to a thickness of about 30 to 60 nm.

In addition, an organic light emitting layer is formed on the hole transport layer. In this case, the organic light emitting layer is formed in a state in which the light emitting material is doped with the light emitting material alone or a host material. For example, in the case of green light emission, about 30 to 60 using Alq3 (tris (8-hydroxy-quinolate) aluminum) as a host and MQD (N-methylquinacridone) as a dopant are often used as organic light emitting layers. It is deposited to a thickness of about nm.

Then, an electron transport layer (ETL) and an electron injection layer (EIL) are formed continuously on the organic emission layer, or an electron injection transport layer is formed. In general, the electron transport layer is deposited to a film thickness of 20 to 50 nm using Alq3, and the electron injection layer is deposited to a film thickness of 30 to 50 nm using an alkali metal derivative. In the case of green light emission, since Alq3 used as an organic light emitting layer has excellent electron transport ability, there are many cases where an electron injection / transport layer is not used.

Next, a second electrode (cathode) is formed on the electron injection layer, and finally a protective film is formed.

In general, in order to implement full-color with an organic light emitting device, a light emitting device emitting three kinds of light of green, red, and blue is required.

Blue is doped with a blue dopant to the blue host, and implemented using Alq3 as the electron transport layer (ETL), Alq3 may be omitted depending on the characteristics of the blue host. In the case of red, a red wavelength may be obtained by doping red impurities instead of green impurities during the device fabrication process. In the case of a red light emitting device, DCM (4-dicyanomethylene-6- (p-dimethylaminostyryl) -2-methyl-4H-pyran) derivatives such as DCM1 and DCM2 are used as dopants.

In the case of the green light emitting device, coumarine 6 or quinacridone derivatives are used as dopants. However, in the case of the green light emitting device, the stability of the device has been evaluated to the practical level, but in the case of the blue light emitting device, the emission color and the stability of the device have not yet reached the practical level, and the luminous efficiency thereof is also satisfactory. There is a problem that is not reached.

As a blue light emitting material, compounds such as diphenylanthracene, tetraphenylbutadiene, and distyrylbenzene derivatives have been developed, but are known to have a tendency to easily crystallize due to poor film stability.

Idemitsu Co., Ltd. has developed a diphenyl distyryl-based blue luminescent material that improves thin film stability by inhibiting crystallization of phenyl groups on side branches [H. Tokilin, H. Higashi, C. Hosokawa, EP 388, 768 (1990)], and Kuju University have developed distyryl anthracene derivatives having improved electron stability and thin film stability with electron donor and electron donor [Pro. SPIE, 1910, 180 (1993)].

However, the molecular structure of the conventional blue light emitting material is a cyclic compound composed mostly of a phenyl group and a double bond, and there is a problem of poor luminous efficiency and color purity. Therefore, in order to develop a blue light emitting element or a full color light emitting element, the development of a new blue light emitting compound is an urgent problem.

Therefore, in order to solve the problem of the blue light emitting device composed mostly of phenyl groups and double bonds, the present invention can introduce triple bonds having less conjugation effect than double bonds, and can emit short wavelengths of light. It is an object to provide a novel blue light emitting material for organic electroluminescent devices.

In addition, the present invention is an organic electroluminescent device containing the blue light emitting compound, more specifically, an organic electroluminescent device in which an organic thin film layer including a light emitting region is provided between a first electrode (anode) and a second electrode (cathode). An object of the present invention is to provide an organic electroluminescent device, characterized in that at least one of the constituent layers of the organic thin film layer contains at least one blue light emitting material according to the present invention.

In order to achieve the above object, the present invention provides a blue light emitting compound for a triple bond-containing organic electroluminescent device represented by the following formula (1), (2) and (3).

[Formula 1]

[Formula 2]

[Formula 3]

In the above formulas,

X ₁ , X ₂ and X ₃ each independently represent an aryl group,

Y ₁ , Y ₂ , Y ₃ , Y ₄ , Y ₅ and Y ₆ each independently represent the following Chemical Formula 4, Chemical Formula 5, Chemical Formula 6 or Chemical Formula 7,

In the above formulas, R ¹ , R ² , R ³ , R ⁴ , R ⁵ and R ⁶ are each independently a hydrogen atom, a halogen group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted group. The substituted aryl group is shown.

In the present invention, the alkyl group refers to a straight or branched chain saturated hydrocarbon group having 1 to 5 carbon atoms, and specifically methyl, ethyl, propyl, isopropyl, butyl, isobutyl, and t-butyl Group, a pentyl group, an isopentyl group, etc. are mentioned, Preferably an ethyl group can be used.

In addition, the alkoxy group is a group containing straight or branched chain alkyl having 1 to 5 carbon atoms, specifically methoxy group, ethoxy group, propoxy group, isopropoxy group, butoxy group, isobutoxy group, t- Butoxy group, a pentoxy group, an isopentoxy group, etc. are mentioned, Preferably an ethoxy group can be used.

The aryl group refers to an aromatic group having 6 to 18 carbon atoms. Specific examples include a phenyl group and a naphthyl group, and preferably a naphthyl group.

In the present invention, the substituent means hydrogen, halogen, cyano, amino, nitro, carboxyl or methyl, ethyl, propyl, butyl, sec-butyl, tert-butyl, pentyl, hexyl However, it is not limited to these substituents.

Representative examples of the triple bond-containing compound of Formulas 1 to 3 are specifically illustrated below. However, the present invention is not limited to the following representative examples.

The present invention also provides an organic electroluminescent device containing the triple bond-containing compound of Formulas 1 to 3, more particularly, an organic thin film layer comprising a light emitting region is provided between the first electrode (anode) and the second electrode (cathode). In an organic electroluminescent device, at least one of the constituent layers of the organic thin film layer contains at least one blue light emitting material according to the present invention.

The compounds of the formulas (1) to (3) used in the present invention may be used alone or in the form of a mixture in any of the above organic thin film layers, and may be used as a host having other materials as a dopant in these layers, and other hole transport materials and light emitting materials. Or an electron transport material or the like as a dopant. Preferably, the compounds according to the invention are used as dopants or hosts in the light emitting layer.

Various embodiments are possible for the organic electroluminescent device produced using the blue light emitting material of the present invention. Basically, the light emitting layer is sandwiched between the pair of electrodes (anode and cathode) (not necessarily required), and a hole injection layer and / or a hole transport layer and / or an electron injection layer and / or an electron transport layer are inserted here as necessary. do. Specific examples of the structure include (1) anode / light emitting layer / cathode, (2) anode / hole transporting layer / light emitting layer / cathode, (3) anode / hole transporting layer / electron transporting layer / cathode, (4) anode / hole injection Layer / hole transport layer / light emitting layer / cathode, (5) anode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / cathode, (6) anode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / electron injection layer / cathode And (7) anode / hole injection layer / light emitting layer / electron injection layer / cathode. It is preferable that each element which has the above-mentioned structure is supported by a board | substrate, respectively. There is no particular limitation on the substrate, and those commonly used in organic electroluminescent devices may be used, for example, glass, transparent plastic, quartz, and the like.

Each layer constituting the organic electroluminescent element of the present invention can be formed by applying a known method, such as a vapor deposition method, a spin coating method, a cast method, or the like, to a material which should constitute each layer, to form a thin film.

The film thickness of each of the layers thus formed, for example, the light emitting layer, is not particularly limited and can be appropriately selected depending on the situation.

As the anode in the organic electroluminescent device of the present invention, a metal, an alloy, an electrically conductive compound having a large work function of 4.0 eV or more, or a mixture thereof can be used as the electrode material. Examples of such electrode materials include conductive transparent or opaque materials such as ITO, SnO ₂ , ZnO, and Au.

In addition, the anode can be produced by forming a thin film by performing a method such as deposition or sputtering of the electrode material described above.

On the other hand, as the cathode, metals, alloys, electroconductive compounds, and mixtures thereof having a work function of 4.2 eV or less can be used as the electrode material. Examples of such electrode materials include calcium, magnesium, lithium, aluminum, magnesium alloys, lithium alloys, aluminum alloys, aluminum / lithium mixtures, magnesium / silver mixtures, indium and the like.

The cathode can be produced by forming a thin film by applying a method such as vapor deposition or sputtering to these electrode materials. In addition, the sheet resistance as the electrode is preferably set to several hundred? / Mm or less, and the film thickness is usually selected in the range of 10 nm to 1 m, preferably 50 to 200 nm.

In the organic electroluminescent device of the present invention, it is preferable that one or both of the anode and the cathode are made transparent or translucent, and the light emission is transmitted to improve the light extraction effect.

Other hole injection materials and hole transport materials that can be used in the organic electroluminescent device of the present invention include those conventionally commonly used as charge transport materials for holes in photoconductive materials, or hole injection layers for organic electroluminescent devices. Any of known materials used for the hole transport layer may be selected and used.

The electron transport layer in the organic electroluminescent device of the present invention contains an electron transport compound and has a function of transferring electrons injected from the cathode to the light emitting layer. There is no restriction | limiting in particular about such an electron transfer compound, Arbitrary thing can be selected and used out of a conventionally well-known compound.

Next, an example of the method suitable for manufacturing the organic electroluminescent element of this invention based on the structure of said (6) is demonstrated.

First, the anode 2 is formed on the transparent substrate 1 by a method such as sputtering, and the hole injection layer 3 and the hole transport layer 4 are sequentially vacuum deposited on the anode. After forming the organic light emitting layer 5 and the electron transport layer 6 on the hole transport layer 4 again by vacuum deposition, an electron injection layer 7 and a cathode 8 are formed on the electron transport layer 6.

The light emitting layer 5 may be a light emitting layer formed by doping one or more compounds of Chemical Formulas 1 to 3 of the present invention to a host conventionally used as a dopant, or may be a single light emitting layer composed of Chemical Formulas 1 to 3 only. have. In addition, the compounds of Formulas 1 to 3 may be mixed with each other as a host and a dopant to form a light emitting layer.

As the material of the anode 2 mentioned above, ITO (In ₂ O ₃ + SnO ₂ ) or IZO (In ₂ O ₃ + ZnO) may be generally used. As the material of the hole injection layer 3, copper phthalocyanine ( copper (II) phthalocyanine) is used. As the hole transport layer 4, triphenylamine or diphenylamine derivatives such as NPD (N, N-di (naphthalen-1-yl) -N, N'-diphenylbenzidine) can be used, and the host material of the light emitting layer 5 can be used. BAlq (Bis- (2-methyl-8-quinolinolato) -4- (phenyl-phenolato) -aluminium- (III)) may be used. In addition, Alq3 can be used as the electron transport layer 6 because of its excellent electron transport properties, and another material that can be used as the electron transport layer 6 is 2- (4-non-phenyl) -5- (4-tert. Oxadiazole and triazole derivatives such as -butylphenyl) -1,3,4-oxadiazole. Alkali metal (Cs, Rb, K, Na, Li) derivatives (Li ₂ O, etc.) may be used as the material of the electron injection layer, and Mg / Ag, Al, Al / Li, Al / Nd as the cathode material. Etc. are possible.

Hereinafter, a synthesis example of a blue light emitting compound of the present invention and an organic electroluminescent device to which the compounds are applied will be described in detail in the following Synthesis Examples and Examples, but the present invention is not limited thereto. It can be carried out in various ways within the scope of the invention described in the appended claims.

Synthesis Example

Synthesis Example 1

Synthesis of Tue 21

1) Synthesis of (4-bromo-phenyl) -diphenyl-amine

1 g (6 mmoles) of diphenylamine was dissolved in 40 ml of toluene, followed by 1.69 g (6 mmoles) of 4-bromo-iodobenzene and 27 mg (0.3 mmoles) of tris (dibenzylideneacetone) dipalladium, 1,1-bis (diphenyl) 33 mg (0.6 mmoles) of phosphino) ferrocene and 570 mg (6 mmoles) of sodium t-butyloxide were added thereto, followed by stirring for 24 hours. After the reaction was completed, 40 ml of water was added, extracted twice with 60 ml of dichloromethane, and concentrated under reduced pressure. The obtained crystals were adsorbed on silica gel and separated by a column (ethyl acetate: hexane = 1: 8) to obtain 900 mg (2.8 mmol, 46% yield) of the product.

2) Synthesis of 4- (4-diphenylamino-phenyl) -2-methyl-but-3-yn-2-ol

900 mg (2.8 mmol) of (4-bromo-phenyl) -diphenyl-amine was dissolved in 40 ml of tetrahydrofuran and 40 ml of triethylamine, 235 mg (2.8 mmol) of 2-methyl-3-butyn-2-ol and bis (tri) Phenylphosphine) -palladium (II) dichloride 20mg (0.28mmole), copper iodide 10mg (0.56mmole) is added and stirred for 24 hours. After the reaction was completed, 80ml of water was added, extracted twice with 100ml of dichloromethane, and concentrated under reduced pressure. The obtained crystals were adsorbed on silica gel and separated by column (ethyl acetate: hexane = 1: 7) to obtain 700 mg (2.1 mmol, 76% yield) of the product.

3) Synthesis of (4-ethynyl-phenyl) -diphenyl-amine

700 mg (2.1 mmol) of 4- (4-diphenylamino-phenyl) -2-methyl-but-3-yn-2-ol was dissolved in 40 ml of benzene, and 50 mg (2.5 mmol) of sodium hydroxide was added thereto, followed by stirring for 5 hours. . When the reaction was completed, 40ml of water was added, extracted twice with 60ml of ethyl acetate and concentrated under reduced pressure. The obtained crystals were recrystallized from a mixture of ethyl acetate and methyl alcohol to obtain 670 mg (2.5 mmol, 95% yield) of the product.

4) Synthesis of Episode 21

Dissolve 500 mg (1.23 mmole) of 4,4-diiodobiphenyl in 30 ml of tetrahydrofuran and 30 ml of triethylamine, and 645 mg (2.4 mmoles) of (4-ethynyl-phenyl) -diphenyl-amine and bis (triphenylphosphine). 10 mg (0.14 mmole) of di-palladium (II) dichloride and 10 mg (0.56 mmole) of copper iodide are added thereto, and the temperature is gradually raised to 70 ° C. while stirring at room temperature, followed by stirring for 24 hours. After the reaction was completed, 60ml of water was slowly added, and the crystals formed by cooling to room temperature were filtered. The filtrate was extracted twice with 50ml of dichloromethane and concentrated under reduced pressure. The obtained crystals were adsorbed on silica gel and separated by a column (ethyl acetate: hexane = 1: 7) to obtain 400 mg (0.58 mmol, 47% yield) of the product.

Synthesis Example 2

54 Synthesis

500 mg (1.9 mmoles) of (4-ethynyl-phenyl) -diphenyl-amine were dissolved in 40 ml of tetrahydrofuran and 40 ml of triethylamine, and 20 mg (0.28 mmoles) of bis (triphenylphosphine) -palladium (II) dichloride. After adding 10 mg (0.56 mmol) of copper iodide, start stirring at room temperature, and slowly raise the temperature to 40 ° C. while injecting oxygen into the solvent and stirring for 12 hours. After the reaction was completed, 80 ml of water was slowly added, cooled to room temperature, extracted twice with 100 ml of dichloromethane, and concentrated under reduced pressure. The obtained crystals were adsorbed on silica gel and separated by a column (ethyl acetate: hexane = 1: 7) to obtain 400 mg (0.78 mmol, 78% yield) of the product. The melting point of the resulting final compound was found to be 146 ° C.

Synthesis Example 3

70 Synthesis

1) Synthesis of [4- (4'-iodo-biphenyl-4-ylethynyl) -phenyl] -diphenyl-amine

Dissolve 500 mg (1.23 mmole) of 4,4-diiodobiphenyl in 30 ml of tetrahydrofuran and 30 ml of triethylamine, and 320 mg (1.2 mmoles) of (4-ethynyl-phenyl) -diphenyl-amine and bis (triphenylphosphine). 10 mg (0.14 mmole) of di-palladium (II) dichloride and 10 mg (0.56 mmole) of copper iodide are added thereto, and the temperature is gradually raised to 70 ° C. while stirring at room temperature, followed by stirring for 24 hours. After the reaction was completed, 60ml of water was slowly added, and the crystals formed by cooling to room temperature were filtered. The filtrate was extracted twice with 50ml of dichloromethane and concentrated under reduced pressure. The obtained crystals were adsorbed on silica gel and separated by column (ethyl acetate: hexane = 1: 7) to obtain 400 mg (0.73 mmol, 59% yield) of the product.

2) Synthesis of 4- [4 '-(4-diphenylamino-phenylethynyl) -biphenyl-4-yl] -2-methyl-but-3-yn-2-ol

700 mg (1.3 mmol) of [4- (4'-iodo-biphenyl-4-ylethynyl) -phenyl] -diphenyl-amine were dissolved in 40 ml of tetrahydrofuran and 40 ml of triethylamine, and 2-methyl-3- 110 mg (1.3 mmol) of butin-2-ol, 20 mg (0.28 mmol) of bis (triphenylphosphine) -palladium (II) dichloride, and 10 mg (0.56 mmol) of copper iodide were added and stirred for 24 hours. After the reaction was completed, 80ml of water was added, extracted twice with 100ml of dichloromethane, and concentrated under reduced pressure. The obtained crystals were adsorbed on silica gel and separated by column (ethyl acetate: hexane = 1: 7) to obtain 400 mg (0.79 mmol, 61% yield) of the product.

3) Synthesis of [4- (4'-ethynyl-biphenyl-4-ylethynyl) -phenyl] -diphenyl-amine

Dissolve 500 mg (1 mmol) of 4- [4 '-(4-diphenylamino-phenylethynyl) -biphenyl-4-yl] -2-methyl-but-3-yn-2-ol in 40 ml of benzene, 40 mg (2 mmoles) of sodium are added and stirred for 5 hours. When the reaction was completed, 40ml of water was added, extracted twice with 60ml of ethyl acetate and concentrated under reduced pressure. The obtained crystals were recrystallized from a mixture of ethyl acetate and methyl alcohol to obtain 400 mg (0.9 mmol, 90% yield) of the product.

4) Synthesis of Tue 70

300 mg (0.55 mmol) of [4- (4'-iodo-biphenyl-4-ylethynyl) -phenyl] -diphenyl-amine were dissolved in 30 ml of tetrahydrofuran and 30 ml of triethylamine, and then [4- (4 ' -Ethylyl-biphenyl-4-ylethynyl) -phenyl] -diphenyl-amine 245 mg (0.55 mmol) and bis (triphenylphosphine)-palladium (II) dichloride 20 mg (0.28 mmol) copper iodide After adding 20mg (1.12mmole), slowly raising the temperature to 70 ℃ while stirring at room temperature and stirred for 24 hours. After the reaction was completed, 60ml of water was slowly added, and the crystals formed by cooling to room temperature were filtered. The filtrate was extracted twice with 50ml of dichloromethane and concentrated under reduced pressure. The obtained crystals were adsorbed on silica gel and separated by a column (ethyl acetate: hexane = 1: 7) to obtain 380 mg (0.44 mmol, 80% yield) of the product.

Other compounds belonging to the formulas (1) to (3) can be prepared by a method similar to the synthesis examples 1 to 3.

EXAMPLE

Example 1

This embodiment is an example in which an organic electroluminescent device is fabricated using the above-described compound of Formula (54) as a blue light emitting dopant and BAlq as a host.

First, copper phthalocyanine (CuPc) was vacuum-deposited on the ultrasonically cleaned ITO deposited glass to form a hole injection layer having a thickness of 30 nm. NPD [N, N-di (naphthalen-1-yl) -N, N'-diphenylbenzidine] was deposited to a thickness of 50 nm on the hole injection layer, and the compound of 54 was added to BAlq (host). Dopant) was doped with 1.0% to form a light emitting layer with a thickness of 30 nm. The electron transport layer (Alq 3; 40 nm), the electron injection layer (Li ₂ O; 25 nm) and the cathode (Mg / Ag; 100 nm) were sequentially vacuum deposited thereon, to fabricate an organic EL device.

Luminescent characteristics were evaluated by applying a forward bias DC voltage to the organic electroluminescent device of Example 1 thus produced. As a result of spectroscopic measurement, a spectrum having an emission peak near 442 nm was obtained. Furthermore, as a result of measuring the voltage-luminance characteristic, the luminance of 3,600 cd / m ² was obtained at 8V, and the efficiency at this time was 1.2 lm / W.

Example 2

This embodiment is an example in which an organic electroluminescent device is fabricated using the above-described compound of Formula 3 (Formula 70) as a blue light emitting dopant and BAlq as a host.

First, copper phthalocyanine (CuPc) was vacuum-deposited on the glass on which ultrasonically cleaned ITO was deposited to form a hole injection layer having a thickness of 30 nm. NPD [N, N-di (naphthalen-1-yl) -N, N'-diphenylbenzidine] was deposited to a thickness of 50 nm on the hole injection layer, and then a compound of 70 was added to BAlq (host). Dopant) was doped with 1.0% to form a light emitting layer with a thickness of 30 nm. The electron transport layer (Alq 3; 40 nm), the electron injection layer (Li ₂ O; 25 nm) and the cathode (Mg / Ag; 100 nm) were sequentially vacuum deposited thereon, to fabricate an organic EL device.

Luminescent characteristics were evaluated by applying a forward bias DC voltage to the organic electroluminescent device of Example 2 thus produced. As a result of spectroscopic measurement, a spectrum having an emission peak near 468 nm was obtained. Moreover, as a result of measuring the voltage-luminance characteristic, the brightness | luminance of 2,800 cd / m <^2> was obtained at 7.8V, and the efficiency at this time was 1.0 lm / W.

Example 3

In this embodiment, the organic electroluminescent device is manufactured by using the compound of Formula 23 (compound of Formula 2) as the blue light emitting host and the compound of Formula 21 (compound of Formula 2) as the dopant of the blue light emitting layer.

First, copper phthalocyanine (CuPc) was vacuum-deposited on the ultrasonically cleaned ITO deposited glass to form a hole injection layer having a thickness of 30 nm. NPD [N, N-di (naphthalen-1-yl) -N, N'-diphenylbenzidine] was deposited to a thickness of 50 nm on the hole injection layer, and then (twa 23) (host) 21) (dopant) was doped with 1.0% to form a light emitting layer with a thickness of 30 nm. The electron transport layer (Alq 3; 40 nm), the electron injection layer (Li ₂ O; 25 nm) and the cathode (Mg / Ag; 100 nm) were sequentially vacuum deposited thereon, to fabricate an organic EL device.

Luminescent characteristics were evaluated by applying a forward bias DC voltage to the organic electroluminescent device of Example 3 thus produced. As a result of spectroscopic measurement, a spectrum having an emission peak near 494 nm was obtained. Moreover, as a result of measuring the voltage-luminance characteristic, the brightness | luminance of 2,700 cd / m <^2> was obtained at 7.5V, and the efficiency at this time was 0.8 lm / W.

The experimental results of Examples 1 to 3 are summarized in Table 1 below.

Host material Dopant material Applied voltage (V) Luminance (cd / m ² ) Efficiency (lm / W) spectrum Example 1 BAlq Tue 54 8 3,600 1.2 442 nm Example 2 BAlq Tue 70 7.8 2,800 1.0 468 nm Example 3 Tue 23 Tue 21 7.5 2,700 0.8 494 nm

The organic electroluminescent device of the present invention using a blue light emitting material incorporating a triple bond having less conjugation effect than a double bond has a smaller wavelength of conjugation than the conventional blue light emitting material, and thus can emit light having a short wavelength. And high quantum efficiency increases the life of the device.

1 is a structural diagram of a general organic electroluminescent device.

<Explanation of symbols for the main parts of the drawings>

1 glass substrate 2 anode

3: hole injection layer 4: hole transport layer

5: light emitting layer 6: electron transport layer

7: electron injection layer 8: cathode

Claims (7)

Compounds, characterized in that selected from the group of triple bond containing compounds of the formula (1) to (3). [Formula 1] [Formula 2] [Formula 3] In the above formulas, X ₁ , X ₂ and X ₃ each independently represent an aryl group, Y ₁ , Y ₂ , Y ₃ , Y ₄ , Y ₅ and Y ₆ each independently represent the following Chemical Formula 4, Chemical Formula 5, Chemical Formula 6 or Chemical Formula 7, [Formula 4] [Formula 5] [Formula 6] [Formula 7] In the above formulas, R ¹ , R ² , R ³ , R ⁴ , R ⁵ and R ⁶ are each independently a hydrogen atom, a halogen group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted group. The substituted aryl group is shown. The compound of claim 1, wherein the compound of Formulas 1 to 3 consists of the following groups. In an organic electroluminescent device in which an organic thin film layer including a light emitting region is provided between a first electrode (anode) and a second electrode (cathode), at least one layer of the constituent layers of the organic thin film layer is claim 1 or 2. An organic electroluminescent device comprising at least one compound represented by the formula (1) to (3). The organic electroluminescent device according to claim 3, wherein the organic thin film layer has a multilayer structure of a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer. The organic electroluminescent device according to claim 4, wherein at least one compound as claimed in claim 1 or 2 is used as a dopant of the light emitting layer. The organic electroluminescent device according to claim 4, wherein at least one compound as claimed in claim 1 or 2 is used as a host of the light emitting layer. The organic electroluminescent device according to claim 4, wherein at least one compound as claimed in claim 1 or 2 is used in combination as a host and a dopant of the light emitting layer.