KR20030074513A - Organic Electroluminescent Compounds Containing Alkene or Diene and Electroluminescent Device Prepared Using the Same - Google Patents

Abstract

PURPOSE: Provided is an organic electroluminescence compound used as a luminescence layer forming material in an organic electroluminescence device, which has excellent blue light emitting efficiency, good stability and long working life. CONSTITUTION: The organic electroluminescence compound used as a luminescence layer forming material in an organic electroluminescence device is represented by the formula of R1-CX=CY-R2, wherein R1 and R2 are identical or different, and each of them represents a substituted or unsubstituted aryl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted pyridyl group, a substituted or unsubstituted heterocyclic group, or a substituted or unsubstituted vinyl group in which X with R1 or Y with R2 can form an interconnected ring structure; X and Y are identical or different, and each of them represents hydrogen, an alkyl group, an acyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted pyridyl group, a substituted or unsubstituted heterocyclic group, or a substituted or unsubstituted vinyl group, except that both of X and Y are hydrogen.

Description

Organic Electroluminescent Compounds Containing Alkene or Diene and Electroluminescent Device Prepared Using the Same}

The present invention relates to an organic electroluminescent compound used as a light emitting layer forming material of an organic electroluminescent device. More specifically, the present invention relates to an organic electroluminescent compound containing an alkene or diene component, which is used as a light emitting layer of an organic electroluminescent device and exhibits excellent blue light emitting properties, mechanical and thermal stability, and an organic electroluminescent device using the same.

Recently, due to the rapid growth of the optical communication and multimedia fields, the development into a highly information society has been accelerated. Accordingly, optoelectronic devices using the conversion of photons to electrons or the conversion of electrons to photons have become the core of the modern information electronics industry. Such semiconductor optoelectronic devices can be broadly classified into electroluminescent devices, light receiving devices, and devices in which these are combined. Until now, most displays are light-receiving, while self-emissive electroluminescence displays are fast response and self-emissive, so they don't need backlighting and have excellent brightness. It is attracting attention as a display element. Electroluminescent devices are classified into inorganic and organic light emitting devices according to the material for forming the light emitting layer. In general, inorganic electroluminescent devices made of pn junctions of inorganic semiconductors such as GaN, ZnS, and SiC have a small area display and light emitting diode due to advantages of high efficiency, small size, long life, and low power consumption. It is used for lamps, semiconductor lasers and the like. However, in the case of an electroluminescent (EL) device made of an inorganic material, a driving voltage is required to be 200 V or more, and the manufacturing method of the device is made by vacuum deposition, which makes it difficult to enlarge the size and to obtain high efficiency blue color.

In order to overcome this problem, a method of manufacturing an electroluminescent device using organic electroluminescence has been reported (Appl. Phys. Letter., 51, p913 (1987); Friend, Nature, 347, p539 (1990)). Organic electroluminescence (EL) is a phenomenon in which when an electric field is applied to an organic material, electrons and holes are transferred from the cathode and the anode, respectively, to be combined within the material, and the energy generated is emitted as light. The electroluminescence of these organic materials was reported by Pope et al. In 1963, and in 1982 by East et al. By Tang et al et al. Since the organic monomolecular thin film electroluminescent device having a multilayer structure having a quantum efficiency of 1% and a luminance of 1000 cd / m 2 at 10 V or less as a device made of a conjugated dye has been developed (US Patent No. 4,356,429). They are easy to synthesize various types of materials because of the simple synthesis path, color tuning is possible, and red, green, and blue can be realized even at a low driving voltage of 10 V or less, and the luminous efficiency and response speed are high. Applications are also being studied in various instrument panels, TVs, and LCD back lights. However, these organic electroluminescent devices have low processability and thermal stability, and when a voltage is applied, Joule heat is generated in the light emitting layer, and as the molecules are rearranged, the devices are destroyed, which causes problems in luminous efficiency or lifetime. Therefore, the development of more efficient and stable devices is required. In particular, the development of a light emitting material having high color purity, luminous efficiency and stability is essential, and the development of a blue light emitting material is attracting the most attention. In relation to this, various researches have been conducted since the development of electromolecules using poly (p-phenylenevinylene), a polymer having conjugated double bonds, by the RH Friend professor team at the University of Cambridge, UK. In particular, high molecular weight compounds such as poly (p-phenylene) (PPP) and low molecular weight compounds such as Alq ' ₂ OPh or para-Sexyphenyl have been used as light emitting materials of blue organic electroluminescent devices. US Patent Nos. 5,121,029 and 5,130,603 to Idemitsu Co., Ltd. disclose that stilbene represented by the following formula (3) or distyrylarylene derivatives represented by the following formula (4) have high brightness even at low driving voltage. It discloses a high stability while exhibiting a blue light emitting performance with:

These compounds are characterized by having at least two vinyl hydrogens (vinylic protons) in the center of the compound, which appears to be due to the production method of Idemitsu, which is due to the fact that there are considerable restrictions on the diversification of the compound structure .

Therefore, conventional blue light emitting materials have a disadvantage in that they cannot provide sufficient stability and driving life due to limitations in luminous efficiency and mechanical and thermal stability. The development of materials is urgent.

Accordingly, the inventors of the present invention conducted extensive research, and it was confirmed that the organic electroluminescent device manufactured using the compound represented by the following Chemical Formula 1 can form a stable light emitting layer having excellent blue light emission efficiency, high color purity, and the present invention. Was completed on this basis.

Accordingly, it is an object of the present invention to provide an electroluminescent compound which exhibits excellent blue light emitting performance and has improved stability and lifespan.

Another object of the present invention to provide an organic electroluminescent device manufactured using the organic electroluminescent compound.

The organic electroluminescent device of the present invention for achieving the above object is represented by the following formula (1) or (2):

Formula 1

Formula 2

In Formula 1 and Formula 2, R ¹ and R ² are the same as or different from each other, and each of an unsubstituted aryl group without a substituent; An aryl group having a substituent; Unsubstituted naphthyl group; Substituted naphthyl group which has a substituent; Unsubstituted pyridyl group without a substituent; Pyridyl group having a substituent (substituted pyridyl group); Unsubstituted heterocyclic groups without substituents; A heterocyclic group having a substituent; Unsubstituted vinyl groups without substituents; Or a vinyl group having a substituent (substituted vinyl group), in Formula 1 X and R ¹ or Y and R ² may form a ring structure connected to each other, in Formula 2 Z ¹ and R ¹ or Z ² And R ² may form a ring structure connected to each other, and in Formula 1 and Formula 2, X, Y, Z ¹ and Z ² are the same as or different from each other, and each hydrogen; Alkyl groups; Acyl group; An unsubstituted aryl group without a substituent; An aryl group having a substituent; Unsubstituted naphthyl group; Substituted naphthyl group which has a substituent; Unsubstituted pyridyl group without a substituent; Pyridyl group having a substituent (substituted pyridyl group); Unsubstituted heterocyclic groups without substituents; A heterocyclic group having a substituent; Unsubstituted vinyl groups without substituents; Or a vinyl group having a substituent (substituted vinyl group), except that X and Y are hydrogen at the same time, in the formula (2) Ar is an unsubstituted arylene group (substituted arylene group) or an arylene group having a substituent ( substituted arylene group) and X and Ar or Y and Ar may form a structure connected to each other, wherein the substituent is an alkyl group, an alkoxy group, an aryl group, or a heterocyclic group. (substituted heterocyclic group), naphthyl group (substituted naphthyl group), pyridyl group (substituted pyridyl group), aryloxy group (aryloxy group), acyl group, acyloxy group (acyloxy group), acyl amino group (acyl amino group group, cyano group, carboxyl group, alkoxycarbonyl group, aryloxycarbonyl group, aminocarbonyl group, carbamoyl group, aranyl group At least one selected from the group consisting of an yl group, a vinyl group, a styryl group, a hydroxyl group, a halogen group, an amino group, and two or more Substituents may form a ring structure connected to each other.

1 is a cross-sectional view showing a structure of an organic electroluminescent device manufactured in the order of a transparent substrate / anode / hole transport layer / light emitting layer / electron transport layer / cathode according to an embodiment of the present invention.

* Explanation of symbols for main parts of the drawings

1: transparent substrate 2: transparent anode

3: hole transport layer 4: light emitting layer

5: electron transport layer 6: cathode

7: power

The invention can be achieved according to the following description with reference to the accompanying drawings.

The organic electroluminescent compound of the present invention is typically used as a light emitting layer forming material positioned between a pair of electrodes in an electroluminescent device, and is represented by the following Chemical Formulas 1 and 2:

Formula 1

Formula 2

In Formula 1 and Formula 2, R ¹ and R ² are the same as or different from each other, and each of an unsubstituted aryl group without a substituent; An aryl group having a substituent; Unsubstituted naphthyl group; Substituted naphthyl group which has a substituent; Unsubstituted pyridyl group without a substituent; Pyridyl group having a substituent (substituted pyridyl group); Unsubstituted heterocyclic groups without substituents; A heterocyclic group having a substituent; Unsubstituted vinyl groups without substituents; Or a vinyl group having a substituent (substituted vinyl group), in Formula 1 X and R ¹ or Y and R ² may form a ring structure connected to each other, in Formula 2 Z ¹ and R ¹ or Z ² And R ² may form a ring structure connected to each other, and in Formula 1 and Formula 2, X, Y, Z ¹ and Z ² are the same as or different from each other, and each hydrogen; Alkyl groups; Acyl group; An unsubstituted aryl group without a substituent; Aryl group having a substituent (substituted aryl group); Unsubstituted naphthyl group; Substituted naphthyl group which has a substituent; Unsubstituted pyridyl group without a substituent; Pyridyl group having a substituent (substituted pyridyl group); Unsubstituted heterocyclic groups without substituents; A heterocyclic group having a substituent; Unsubstituted vinyl groups without substituents; Or a vinyl group having a substituent (substituted vinyl group), except that X and Y are hydrogen at the same time, in the formula (2) Ar is an unsubstituted arylene group (substituted arylene group) or an arylene group having a substituent ( substituted arylene group) and X and Ar or Y and Ar may form a structure connected to each other, wherein the substituent is an alkyl group, an alkoxy group, an aryl group, or a heterocyclic group. (substituted heterocyclic group), naphthyl group (substituted naphthyl group), pyridyl group (substituted pyridyl group), aryloxy group (aryloxy group), acyl group, acyloxy group (acyloxy group), acyl amino group (acyl amino group group, cyano group, carboxyl group, alkoxycarbonyl group, aryloxycarbonyl group, aminocarbonyl group, carbamoyl group, aranyl group At least one selected from the group consisting of an yl group, a vinyl group, a styryl group, a hydroxyl group, a halogen group, an amino group, and two or more Substituents may form a ring structure connected to each other.

Ar in the formula (2) is preferably an arylene below or a group to which at least one of the substituents is attached.

In addition, in Formula 1 and Formula 2, R ¹ and R ² are each represented by phenyl, tolyl, biphenyl, terphenyl, and one or more of the substituents attached thereto. It is preferably selected from the group consisting of, X, Y, Z ¹ and Z ² are methyl, ethyl, propyl, butyl, pentyl, hexyl, cyclohexyl, benzyl, phenyl, tolyl and at least one of the above substituents attached thereto. It is preferably selected from the group consisting of groups.

An example of a method of preparing the compound of Formula 1 is as follows.

Phosphors such as diethyl benzylphosphonate, diethyl 4-methyl benzylphosphonate, diethyl-1-naphthylmethylphosphonate, and the like The nate compound is dissolved in a solvent such as ether, THF, dimethoxyethene (1,2-dimethoxyethane), and then added with a base such as NaH, KH, LDA, and stirred for about 0.5 to 1 hour, followed by diaryl ketone and aryl. Carbonyl compounds, such as an alkyl ketone and an arylaldehyde, are stirred slowly, dropwise. After the reaction is completed, the reaction solution is worked up, and then the product is purified by appropriate methods such as recrystallization, column chromatography, distillation, sublimation, and the like.

On the other hand, an example of a method of preparing the compound of Formula 2 is as follows.

Phosphors such as diethyl benzylphosphonate, diethyl 4-methyl benzylphosphonate, diethyl-1-naphthylmethylphosphonate Nate compound was dissolved in a solvent such as ether, THF, dimethoxyethene (1,2-dimethoxyethene, etc.), and then added with a base such as NaH, KH, LDA, and stirred for about 0.5 to 1 hour, followed by 1,4-diacetyl Dicarbonyl compounds such as benzene (1,4-diacetylbenzene) and 4,4'-diacetylbiphenyl are slowly added dropwise and stirred, after which the reaction solution is worked up. The product is then purified by suitable methods such as recrystallization, column chromatography, distillation, sublimation, and the like.

The structure and purity of the resulting compound can be analyzed using ¹ H-NMR, ¹³ C-NMR, elemental analysis, DIP-MA and the like.

The organic electroluminescent compound prepared according to the present invention forms a light emitting layer of such an organic electroluminescent device, and the organic electroluminescent device to which the organic electroluminescent device is applied is manufactured as follows.

First, an anode electrode material is coated on the substrate. Herein, a substrate used in a conventional organic electroluminescent device is used, and a glass substrate or a transparent plastic substrate having excellent transparency, surface smoothness, ease of handling, and waterproofness is preferable. In addition, as the anode electrode material, indium tin oxide (ITO), tin oxide (SnO ₂ ), zinc oxide (ZnO), or the like, which is transparent and has excellent conductivity, is used. As the cathode forming metal, lithium (Li), magnesium (Mg), aluminum (Al), Al: Li, Mg: In, and the like having a small work function may be used.

The configuration of the electroluminescent device using the organic electroluminescent compound of the present invention as a light emitting layer is not only usable for the most common device configuration of the anode / light emitting layer / cathode, but also further includes a hole transport layer and / or an electron transport layer as shown in FIG. can do.

In the present invention, the light emitting layer can be formed by a deposition method or a spin coating method which is generally used, and the thickness thereof preferably has a range of 50 to 5000 nm.

In addition, the hole transport layer and the electron transport layer may be used a material commonly used in the art, as the hole transport layer material N, N'-diphenyl-N, N'-bis- (3-methylphenyl)-[1, 1'-biphenyl] -4,4'-diamine (TPDA), 4,4'-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (α-NPD) and the like can be used. As the electron transport layer material, aluminum trihydroxyquinoline (Alq ₃ ), 1,3,4-oxadiazole derivative PBD (2- (4-biphenylyl) -5-phenyl-1,3,4- oxadiazole), TPQ (1,3,4-tris [(3-penyl-6-trifluoromethyl) quinoxaline-2-yl] benzene), which is a quinoxaline derivative, and triazole derivatives. The electron transport layer and the hole transport layer serves to increase the probability of light emitting coupling in the light emitting material by efficiently transporting the carriers to the light emitting material. In addition, the hole transport layer and the electron transport layer may be formed by a deposition method, a spin coating method or a casting method, the layer thickness is preferably 20 to 2000nm.

The present invention can be more clearly understood by the following examples, which are only intended to illustrate the present invention and are not intended to limit the scope of the invention.

Example 1

Synthesis of Phenylalkene Compound (Formula 6)

(1) Synthesis of Diaryl Ketone (Formula 5)

2.611 g (10 mmole) of 4-bromobenzophenone, 1.628 g (11 mmole) of 4-vinylphenylboronic acid and tetrakis (triphenylphosphine) palladium [Tetrakis (4) triphenyl phosphine) palladium] 0.347 g (0.3 mmole) was dissolved in 12 ml of benzene, 10 ml of 2M Na ₂ CO ₃ aqueous solution and 5 ml of ethyl alcohol were added thereto, and the mixture was stirred at reflux for 7 hours. After the completion of stirring, 0.3 ml of 30% hydrogen peroxide solution was added thereto, stirred for 1 hour, diluted with ether, washed 3-4 times with water, dried over MgSO ₄ to remove the solvent, and a solid material was obtained. The obtained solid was recrystallized from a solution in which isopropanol ( iso- propanol) and ethyl acetate (ethyl acetate) were mixed at a weight ratio of 95: 5 to obtain 2.62 g (92%) of a white solid compound. The solid compound was analyzed for physical properties and structure through instrumental analysis, and the following results were obtained.

Melting Point: 147∼149 ℃

¹ H NMR (300 MHz, CDCl ₃ ): δ5.33 ppm (d, J = 11.1 Hz, 1H, terminal vinyl group, = CH ₂ ), δ5.84 ppm (d, J = 17.7 Hz, 1H, terminal vinyl group, = CH ₂ ), δ6.79 ppm (dd, J = 17.7 Hz and J = 11.1 Hz, 1H, terminal vinyl group, = CH-), δ 7.49-7.93 ppm (m, 13H, aromatic ring -H )

Elemental Analysis: C: 88.58, H: 5.71 (Theoretic: C: 88.70, H: 5.67)

DIP-MS: 284

From the results, it was confirmed that the product of the reaction was a diaryl ketone, which is a compound represented by the following Chemical Formula 5.

(2) Synthesis of Phenylalkene Compound

0.5 g (2.19 mmol) of diethyl benzylphosphonate and 0.26 g (6.57 mmol) of NaH (60%) were added to 20 ml of 1,2-dimethoxyethane. After stirring for 30 minutes, a solution in which 0.685 g (2.41 mmol) of diaryl ketone was dissolved in a small amount of DME was slowly added dropwise and refluxed for about 30 minutes. The reaction solution was washed with 1% aqueous hydrochloric acid (HCl) solution, distilled water, and saturated sodium chloride solution, and then the solvent was removed. The mixture was purified by recrystallization. A pale yellow solid compound (78%) 0.61 g was obtained. By analyzing the physical properties and structure of the solid compound through the instrumental analysis was obtained the following results.

Melting Point: 115 ~ 117 ℃

¹ H NMR (300 MHz, CDCl ₃ ): δ 5.28 ppm (d, J = 10.8 Hz, 1H, terminal vinyl group, = CH ₂ ), δ 5.79 ppm (d, J = 17.7 Hz, 1H, terminal vinyl group, = CH ₂ ), δ6.83 ppm (dd, J = 17.7 Hz and J = 10.8 Hz, 1H, terminal vinyl group, = CH-), δ 7.27-7.6 ppm (m, 19H, aromatic ring -H And methylidyne, -CH = C-)

Elemental Analysis: C: 93.79, H: 6.21 (Theoretical: C: 93.83, H: 6.17)

DIP-MS: 358

From the results, it was confirmed that the product of the reaction was a phenylalkene compound represented by the following formula (6).

Example 2

Synthesis of Naphthyl Alkene Compound (Formula 7)

Diaryl ketone represented by the formula (5) was synthesized in the same manner as in Example 1.

0.68 g (2.46 mmol) of diethyl-1-naphthylmethylphosphonate and 0.147 g (3.69 mmol) of NaH were added to 1,2-dimethoxyethane. After addition to mL and stirring for 30 min, a solution of 0.35 g (1.23 mmol) of diarylketone in a small amount of DME was refluxed slowly dropwise for about 30 min. The reaction solution was washed with 1% aqueous hydrochloric acid (HCl) solution, distilled water, and saturated sodium chloride, and then the solvent was removed. The mixture was purified by recrystallization to obtain 0.75 g of a pale yellow solid compound (75%). By analyzing the physical properties and structure of the solid compound through the instrumental analysis was obtained the following results.

Melting Point: 131 ~ 132 ℃

¹ H NMR (300 MHz, CDCl ₃ ): δ5.33 ppm (d, J = 11.7 Hz, 1H, terminal vinyl group, = CH ₂ ), δ5.84 ppm (d, J = 17.4 Hz, 1H, terminal vinyl group, = CH ₂ ), δ6.79 ppm (dd, J = 17.7 Hz and J = 10.8 Hz, 1H, terminal vinyl group, = CH-), δ7.30-7.92 ppm (m, 21H, aromatic ring -H And methylidyne, -CH = C-)

Elemental Analysis: C: 94.11, H: 5.89 (Theoretical: C: 94.08, H: 5.92)

DIP-MS: 408

From the results, it was confirmed that the product of the reaction was a naphthyl alkene compound represented by the following Chemical Formula 7.

Example 3

Tolyl diene compound synthesis (Formula 9)

(1) Synthesis of Dicarbonyl Compound (Formula 8)

1.583 g (6.063 mmole) of 4-bromobenzophenone, 1 g (6.669 mmole) of 4-formylphenylboronic acid and tetrakis (triphenylphosphine) palladium [Tetrakis ( triphenyl phosphine) palladium] 0.21 g (0.182 mmole) was dissolved in 12 ml of benzene, 6 ml of 2M Na ₂ CO ₃ aqueous solution and 3 ml of ethyl alcohol were added, and the mixture was stirred at reflux for 7 hours. 0.3 ml of 30% hydrogen peroxide solution, stirred for 1 hour, diluted with ether, washed 3-4 times with water, dried over MgSO ₄ , removed solvent and the obtained solid wasopropanol ( iso- propanol) and ethyl 1.85 g of a white solid compound (84%) was obtained by recrystallization of a solution mixed with 95: 5 by weight of acetate (ethyl acetate). By analyzing the physical properties and structure of the solid compound through the instrumental analysis was obtained the following results.

Melting Point: 128 ~ 130 ℃

¹ H NMR (300 MHz, CDCl ₃ ): δ 7.53-8.05 ppm (m, 13H, aromatic ring -H), δ 10.11 ppm (s, 1H, aldehyde, H-CO-)

Elemental Analysis: C: 88.78, H: 4.96 (Theoretical: C: 88.89, H: 4.93)

DIP-MS: 286

From the results, it was confirmed that the product of the reaction was a dicarbonyl compound represented by the following Formula 8.

(2) Synthesis of Tolyl Diene Compound (Formula 9)

0.25 g (0.874 mmole) of dicarbonyl compound, 0.534 g (2.185 mmole) of diethyl 4-methyl benzylphosphonate and 0.063 g (2.622 mmole) of NaH were added to 20 ml of dimethoxyethane. After dissolving in, it was stirred for 12 hours at reflux conditions. The stirred reaction solution was washed with 10% aqueous hydrochloric acid solution and water, and then the solvent was removed. The yellow solid was purified by column chromatography, obtaining 0.258 g of a pale yellow solid compound (64%). The solid compound was analyzed by instrumental analysis, and the results were as follows.

Melting Point: 140 ~ 142 ℃

¹ H NMR (300 MHz, CDCl ₃ ): δ 2.28 ppm (s, 3H, p -tolylmethyl group, = CH ₃ ), δ 2.38 ppm (s, 3H, p -tolylmethyl group, = CH ₃ ), δ 6 .95-7.75 ppm (m, 24H, aromatic ring -H and methylidyne, -CH = C-)

Elemental Analysis: C: 93.43, H: 6.57 (Theoretical: C: 93.46, H: 6.54)

DIP-MS: 462

From the results, it was confirmed that the product of the reaction was a tolyl diene compound represented by the following formula (9).

Example 4

Synthesis of Naphthyl Diene Compound (Formula 10)

A dicarbonyl compound of Chemical Formula 8 was synthesized in the same manner as in Example (1).

0.25 g (0.874 mmole) of dicarbonyl compound, 0.608 g (2.185 mmole) of diethyl-1-naphthylmethylphosphonate and 0.063 g (2.622 mmole) of NaH were added to dimethoxyethane 20. It was dissolved in ㎖ and stirred for 12 hours at reflux conditions. The reaction solution was washed with 10% aqueous hydrochloric acid solution and water, and then the solvent was removed. The yellow solid obtained was purified by column chromatography, obtaining 0.282 g of a pale yellow solid compound (61%). The results of analyzing the physical properties and the structure of the compound through instrumental analysis were as follows.

Melting Point: 169 ~ 171 ℃

¹ H NMR (300 MHz, CDCl ₃ ): δ 7.20-8.28 ppm (m, 30H, aromatic ring -H and methylidyne, -CH = C-)

Elemental Analysis: C: 93.35, H: 5.65 (Theory: C: 94.34, H: 5.66)

DIP-MS: 534

From the results, it was confirmed that the product of the reaction was a naphthyl diene compound represented by the following Chemical Formula 10.

Example 5

Manufacture of organic electroluminescent device

Organic electroluminescent devices using the compounds represented by Chemical Formulas 6, 7, 9, and 10, respectively, were produced by the following method.

After forming an Indium-tin oxide (ITO) electrode on a glass substrate (20 mm x 25 mm), a polyaniline-polyvinylcarbazole (1: 9) blend solution (solvent: m-cresol: chloroform = 7: 3) was 5000 After spin-coating for 100 seconds at rpm, the solvent was removed by drying at 55 ° C. over 15 hours in a vacuum of 1 × 10 ⁻⁵ Torr or less. The substrate obtained as described above, 1.5 × 10 ^-6 into a vacuum chamber, which is kept below Torr TPDA (N, N-diphenyl- N, N- bis - (3-methylphenyl) - [1,1 -biphenyl] -4, 4-diamine) was thermally evaporated at a rate of 0.2-0.3 nm / s to form a hole injection layer having a thickness of 60 nm. Subsequently, the electroluminescent compound sample was thermally deposited at a rate of 0.2 to 0.3 nm to form a light emitting layer having a thickness of 80 nm. A 150 nm thick Mg-In mixed electrode was formed on the light emitting layer by placing a stainless steel mask on the light emitting layer and simultaneously depositing magnesium at a rate of 2 to 3 nm / s and indium at a rate of 0.04 to 0.08 nm / s. The ITO electrode was used as the anode and the Mg-In electrode as the cathode, and a direct current voltage was applied to observe current, emission wavelength, luminance, lifetime, and emission stability. The properties of the devices are shown in Table 1 below.

Chemical formula DC (V) Current density (mA / ㎠) color Emission wavelength (nm) Luminance (cd / ㎡) Life (hr) Luminous stability 6 9 15 blue 470 900 > 10,000 stability 7 7 9 Cyan 486 530 > 10,000 stability 9 10 37 Indigo blue 442 2100 > 20,000 stability 10 10 32 Cyan 483 1700 > 20,000 stability

The organic light emitting compound according to the present invention is not only can be used as the light emitting layer of the electroluminescent device having excellent performance because of the excellent luminous efficiency, high color purity and excellent stability of the blue series, as well as light emitting layers such as plasma panel displays and various displays. It can also be usefully used as a fluorescent color filter of the device.

All simple modifications and variations of the present invention fall within the scope of the present invention, and the specific scope of the present invention will be apparent from the appended claims.

Claims (5)

An organic electroluminescent compound represented by Chemical Formula 1 and used as a material for forming an emission layer of an organic electroluminescent device: Formula 1 In Chemical Formula 1, R ¹ and R ² are the same as or different from each other, and are each an unsubstituted aryl group without a substituent; An aryl group having a substituent; Unsubstituted naphthyl group; Substituted naphthyl group which has a substituent; Unsubstituted pyridyl group without a substituent; Pyridyl group having a substituent (substituted pyridyl group); Unsubstituted heterocyclic groups without substituents; A heterocyclic group having a substituent; Unsubstituted vinyl groups without substituents; Or a vinyl group having a substituent (substituted vinyl group), in Formula 1 X and R ¹ or Y and R ² may form a ring structure connected to each other, X and Y are the same as or different from each other, and each hydrogen; Alkyl groups; Acyl group; An unsubstituted aryl group without a substituent; An aryl group having a substituent; Unsubstituted naphthyl groups without substituents; Substituted naphthyl group which has a substituent; Unsubstituted pyridyl group without a substituent; Pyridyl group having a substituent (substituted pyridyl group); Unsubstituted heterocyclic groups without substituents; A heterocyclic group having a substituent; Unsubstituted vinyl groups without substituents; Or a vinyl group having a substituent, except that X and Y are hydrogen at the same time, The substituent is an alkyl group, an alkoxy group, an aryl group, a heterocyclic group, a substituted naphthyl group, a substituted pyridyl group, Aryloxy group, acyl group, acyloxy group, acyloxy group, acyl amino group, cyano group, cyano group, carboxyl group, alkoxycarbonyl group , Aryloxycarbonyl group (aryloxycarbonyl group), aminocarbonyl group (aminocarbonyl group), carbamoyl group (carbamoyl group), arranyl group (aranyl group), vinyl group (vinyl group), styryl group (hydroxyl group), hydroxyl group (hydroxyl group) group), a halogen group, and at least one selected from the group consisting of an amino group (amino group), two or more substituents may form a ring structure connected to each other. The compound of claim 1, wherein R ¹ and R ² are each selected from the group consisting of phenyl, tolyl, biphenyl, terphenyl, and groups in which at least one of the substituents is attached thereto. An organic electroluminescent compound, characterized in that selected. The method according to claim 1, wherein X and Y are each selected from the group consisting of methyl, ethyl, propyl, butyl, pentyl, hexyl, cyclohexyl, benzyl, phenyl, tolyl and groups having one or more of the above substituents attached thereto. An organic electroluminescent compound characterized by. An organic electroluminescent device comprising using the organic light emitting compound according to any one of claims 1 to 3 as a material for forming a light emitting layer. The organic electroluminescent device according to claim 4, wherein the structure of the electroluminescent device is an anode / hole transporting layer / light emitting layer / electron transporting layer / cathode.