KR101794132B1 - Red color phosphorescent host material and Organic electroluminescent display device using the same - Google Patents

Abstract

또한, 본 발명은 하기 화학식으로 표시되며, Ar1 및 Ar2 각각은 치환 또는 비치환된 방향족 그룹 물질, 치환 또는 비치환된 이형고리 그룹 물질, 또는 치환 또는 비치환된 방향족 그룹 물질에서 선택되는 것이 특징인 유기전계발광소자용 적색 인광 호스트 물질을 제공한다.

The present invention is represented by the following formula: wherein each of A 1 and A 2 is selected from a substituted or unsubstituted aromatic group material, a substituted or unsubstituted aliphatic ring group material, or a substituted or unsubstituted aromatic group material. A red phosphorescent host material for a light emitting device is provided.

In addition, the present invention is represented by the following formula: wherein each of Ar1 and Ar2 is selected from a substituted or unsubstituted aromatic group material, a substituted or unsubstituted aliphatic ring group material, or a substituted or unsubstituted aromatic group material A red phosphorescent host material for an organic electroluminescent device is provided.

Description

[0001] The present invention relates to a red phosphorescent host material and an organic electroluminescent device using the phosphorescent host material,

The present invention relates to a red phosphorescent host material and an organic electroluminescent device using the same. More particularly, the present invention relates to a red phosphorescent host material capable of dissolving and having excellent brightness and luminous efficiency, and an organic electroluminescent device comprising the same.

In recent years, the demand for a flat display device having a small space occupancy has been increased due to the enlargement of the display device. The technology of the organic electroluminescent device, which is also called an organic light emitting diode (OLED) And several prototypes have already been announced.

An organic electroluminescent device is a device that injects electric charge into a light emitting material layer formed between an electron injecting electrode (cathode) and a hole injecting electrode (anode) to form an electron and a hole. The device can be formed on a flexible transparent substrate such as a plastic substrate and can be driven at a lower voltage (10 V or less) than a plasma display panel or an inorganic electroluminescence (EL) It also has the advantage of low power consumption and excellent color. In addition, organic electroluminescence (EL) devices can display three colors of green, blue, and red, making them a next-generation rich color display device and attracting a lot of interest from many people. Here, the process of fabricating the organic electroluminescent device will be briefly described.

(1) First, a material such as indium tin oxide (ITO) is deposited on a transparent substrate to form an anode.

(2) A hole injecting layer (HIL) is formed on the anode. The hole injection layer is mainly formed by depositing copper phthalocyanine (CuPc) represented by the following formula 1-1 to a thickness of 10 nm to 30 nm.

(3) Next, a hole transport layer (HTL) is formed on the hole injection layer. This hole transport layer is formed by depositing 4,4'-bis [N- (1-naphtyl) -N-phenylamino] -biphenyl (NPD)

(4) Next, an emitting material layer (EML) is formed on the hole transport layer. At this time, a dopant is added as needed.

For example, the red light emitting layer, the green light emitting layer, and the blue light emitting layer constitute one pixel to represent various grayscales. For example, a red light emitting layer is formed by depositing 4, 4'-N, N'-dicarbazolbiphenyl (CBP) represented by the following Chemical Formula 1-3 at a thickness of 30 nm to 60 nm, -4 or 1-5 is mainly used.

(5) Next, an electron transport layer (ETL) and an electron injecting layer (EIL) are successively formed on the light emitting material layer. At this time, the electron transport layer is composed of tris (8-hydroxy-quinolate) aluminum (Alq3) represented by the following Chemical Formula 1-6.

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

Formula 1 -One

Formula 1 -2

Formula 1 -3

Formula 1 -4

Formula 1 -5

Formula 1 -6

In the above structure, the light emitting material layer implements blue, green, and red colors, thereby realizing a full-color image.

In the case of the luminescent material, excitons are formed by recombination of electrons and holes injected from both electrodes. Fluorescence in singlet excitons and phosphorescence in triplet excitons are involved. In the case of triplet excitons having a generation probability of 75% which is involved in the phosphorescent material, the luminous efficiency is higher than that of fluorescent materials using singlet excitons with a generation probability of 25%. Among these phosphorescent materials, the red phosphorescent material can have a very high luminous efficiency as compared with the fluorescent material, and thus much research has been conducted as an important method for increasing the efficiency of the organic electroluminescent device.

In order to use the phosphorescent material, a high luminous efficiency, a high color purity and a long luminous lifetime are required. In the case of the red color, the visibility decreases as the color purity (X value of the CIE color coordinate increases) There is a problem that it is difficult to obtain high luminous efficiency with efficiency. Accordingly, development of a red phosphor having excellent color purity (CIE color purity X = 0.65 or more) and high luminous efficiency has been demanded.

On the other hand, CBP or a metal complex is used as a red phosphorescent host material, but these materials have a disadvantage in that the process efficiency is inferior because they are formed due to poor solubility through a deposition process.

There is a great limitation in forming a large-sized device.

The present invention aims to provide a red phosphorescent host material which is excellent in solubility and can be subjected to a solution process and has excellent brightness and luminous efficiency.

Also, a large area organic electroluminescent device capable of realizing a high brightness image using the red phosphorescent host material is provided.

In order to solve the above problems, the present invention is represented by the following formula: wherein each of A 1 and A 2 is a substituted or unsubstituted aromatic group material, a substituted or unsubstituted aliphatic ring group material, or a substituted or unsubstituted aromatic group material And a red phosphorescent host material for an organic electroluminescence device.

In addition, the present invention is represented by the following formula: wherein each of Ar1 and Ar2 is selected from a substituted or unsubstituted aromatic group material, a substituted or unsubstituted aliphatic ring group material, or a substituted or unsubstituted aromatic group material A red phosphorescent host material for an organic electroluminescent device is provided.

The aromatic group material is characterized by including phenyl, naphthyl, biphenyl, terphenyl, and phenanthrenyl.

The modified ring group material is selected from the group consisting of pyridinyl, bipyridinyl, quinolinyl, isoquinolinyl, quinoxalinyl, terpyridinyl, phenanthrolinyl, phenanthrolinyl).

The aliphatic group material is characterized by containing C1 to C20 aryl and C1 to C20 alkyl.

The aromatic group material, the modified ring group material, and the aromatic group material may be substituted by C1-C20 aryl, C1-C20 alkyl, C1-C20 alkoxy, halogen, Cyano, and silyl. The term " alkyl "

In another aspect, the present invention provides a liquid crystal display comprising: a first electrode; A second electrode facing the first electrode; And a light emitting material layer disposed between the first and second electrodes, wherein the light emitting material layer is represented by the following formula: wherein each of A 1 and A 2 is a substituted or unsubstituted aromatic group material, a substituted or unsubstituted Wherein the organic material is selected from the group consisting of a halogen group, a cyclic group material, and a substituted or unsubstituted aromatic group material.

According to another aspect of the present invention, A second electrode facing the first electrode; And a light emitting material layer disposed between the first and second electrodes, wherein the light emitting material layer is represented by the following formula: wherein each of Ar1 and Ar2 is a substituted or unsubstituted aromatic group material, a substituted or unsubstituted Wherein the organic material is selected from the group consisting of a halogen group, a cyclic group material, and a substituted or unsubstituted aromatic group material.

The red phosphorescent host material is soluble in a non-polar solvent and is formed by a coating process.

Since the red phosphorescent host material of the present invention is excellent in solubility, it has an advantage that a film can be formed by a solution process. Thus, the manufacture of the large-area organic electroluminescent device becomes easy.

In addition, the organic electroluminescent device using the red phosphorescent host material can realize a high-brightness image and reduce power consumption.

FIGS. 1A and 1B are graphs showing PL spectra of a red phosphorescent host material according to an embodiment of the present invention. FIG.
2 is a schematic cross-sectional view of an organic electroluminescent device according to an embodiment of the present invention.

Hereinafter, the structure of the red phosphorescent host material according to the present invention, its synthesis example, and the organic electroluminescent device using the red phosphorescent host material will be described.

- First Embodiment -

The red phosphorescent host material according to the first embodiment of the present invention is characterized in that the 3,4 benzo carbazole is bonded to the para position and the nitrogen of the carbazole is substituted with a substance selected from an aromatic group, an aliphatic ring group or an aliphatic group, And has the following formula (2).

(2)

Wherein each of Al and A2 is selected from a substituted or unsubstituted aromatic group material, a substituted or unsubstituted aliphatic ring group material, or a substituted or unsubstituted aromatic group material. In case A1 and A2 are the same, they have a symmetrical structure. On the other hand, when A1 and A2 are different, they have an asymmetric structure.

For example, the aromatic group material may include phenyl, naphthyl, biphenyl, terphenyl, and phenanthrenyl.

The modified ring group material may be at least one selected from the group consisting of pyridinyl, bipyridinyl, quinolinyl, isoquinolinyl, quinoxalinyl, terpyridinyl, It is characterized by containing phenanthrolinyl.

In addition, the aliphatic group material is characterized by containing C1 to C20 aryl and C1 to C20 alkyl.

The aromatic group material, the aliphatic group material, and the aromatic group material may be substituted by C1-C20 aryl, C1-C20 alkyl, C1-C20 alkoxy, halogen, ), Cyano, and silyl. For example, the substituent may be selected from the group consisting of methyl, ethyl, propyl, isopropyl, t-butyl, methoxy, ethoxy, butoxy butoxy, trimethylsilyl, fluorine, and chlorine.

Such a red phosphorescent host material is characterized in that the 3,4 benzo carbazole of carbazole is bonded to the para position and the nitrogen of the carbazole is substituted with a material selected from an aromatic group, . In addition, it has advantages of high brightness and high efficiency.

For example, each of A1 and A2 may be selected from a plurality of substance groups represented by the following formula (3).

(3)

According to the selection of A1 and A2, the red phosphorescent host material of Formula 2 is any one of a plurality of materials represented by Formula 4 below. Here, for ease of explanation, symbols RH001 to RH309 are assigned to the bottom of each material.

Formula 4

Hereinafter, a synthesis example of the red phosphorescent host material for an organic electroluminescence device according to the present invention will be described with reference to a red phosphorescent host material represented by RH-001 in the formula (4).

Synthetic example

1. Synthesis of 3-bromo-dihydrobenzo [3,4] carbazole

3-bromo-dihydrobenzo [3,4] carbazole is synthesized according to Reaction Scheme 1 below.

Scheme 1

Specifically, β-teralone (25 g, 0.17 mol), 4-bromophenylhydrazinuim chloride (38.2 g, 0.17 mol) and acetic acid are added to ethanol in a 2-round flask and refluxed for 1 hour. The temperature is lowered to room temperature, followed by filtering and evaporating the solvent. Add zinc chloride (58 g, 0.42 mol) and acetic acid and reflux for 30 minutes. After the temperature was lowered to room temperature, the solvent was evaporated and precipitated with MC / PE to obtain 3-bromo-dihydrobenzo [3,4] carbazole (35.5 g, yield: 70%).

2. Synthesis of 3-bromobenzo [3,4] carbazole

3-bromobenzo [3,4] carbazole is synthesized by the following reaction formula 2.

Scheme 2

Specifically, 3-bromodihydrobenzo [3,4] carbazole (20 g, 0.07 mol), 2,3-dichloro-5,6-dicyanobenzoquinone (19.8 g, 0.09 mol) and benzene were placed in a two- Lt; / RTI > for 1 hour. Ethyl acetate was extracted and the solvent was evaporated and purified by silica gel column to give 3-bromobenzo [3,4] carbazole (15.9 g, yield: 80%).

3. Synthesis of 3-bromo-9-phenylbenzo [3,4] carbazole

3-bromo-9-phenylbenzo [3,4] carbazole is synthesized by the following reaction formula (3).

Scheme 3

Specifically, 3-bromobenzo [3,4] carbazole (5g, 0.017mol), bromobenzene (4g, 0.025mol), Pd2 (dba) 3 (0.42g, 0.046mol% Bu) 3 (0.14g, 0.069mol%), NaOBu (2.4g, 0.025mol) and toluene, and refluxed at 130 ° C for 6 hours. The reaction mixture was cooled to room temperature and extracted with methylene chloride. The solvent was evaporated and purified by silica gel column to obtain 3-bromo-9-phenylbenzo [3,4] carbazole (5 g, yield: 80%).

4. Synthesis of 9-phenybenzo [3,4] carbazole-3-boronic acid

9-phenybenzo [3,4] carbazole-3-boronic acid is synthesized by the following reaction formula (4).

Scheme 4

Specifically, 3-bromo-9-phenylbenzo [3,4] carbazole (10 g, 0.026 mol) and 100 mL of ether are added to a two-necked round flask and stirred. The temperature is lowered to -78 ° C with a dry-ice bath, then 2.5M n-BuLi (11.8mL, 0.03mol) is slowly dropped and stirred at room temperature for 1 hour. The temperature is lowered to -78 ° C with a dry-ice bath, then triethylborate (10.1 g, 0.05 mol) is slowly dropped and stirred at room temperature for 4 hours. 100 mL of 2N HCl is added and quenched, and the solvent is evaporated. The resulting crystals were filtered and washed with distilled water and hexane 3-4 times to give 9-phenylbenzo [3,4] carbazole-3-boronic acid acid (6.1 g, yield: 70%).

5. Synthesis of RH-001

The red phosphorescent host material represented by RH-001 in formula (4) is synthesized by the following reaction formula (5).

Scheme 5

Specifically, 3-bromo-9-phenylbenzo [3,4] carbazole (2 g, 5.4 mmol), 9-phenylbenzo [3,4] carbazole-3-boronic acid (1.8 g, 5.4 mmol) (PPh3) 4 in THF / H2O (20 mL / 20 mL) and reflux for 8 hours. After confirming the reaction with TLC (Thin-Layer Chromatography), the temperature was lowered to room temperature, extracted with methylene chloride, the solvent was evaporated, and purified by silica gel column to obtain RH-001 (2.2 g, yield: 70%).

Hereinafter, the present invention will be described in more detail with reference to Examples 1 to 5 of the organic electroluminescent device using the red phosphorescent host material according to the first embodiment of the present invention, The performance of the light emitting device will be described below.

Experimental Example 1

The ITO layer was patterned to have a light emitting area of 3 mm x 3 mm on the substrate and then cleaned. A light emitting layer (200 Å) doped with 5% of a dopant represented by RD-1 represented by the above Chemical Formulas 1-4 to a red phosphorescent host material represented by RH-002 in the above Chemical Formula 4, Cuq (650 Å), NPD (350 Å), LiF (5 Å), and Al (1000 Å).

(5.4 V) at 0.9 mA, and CIE x = 0.658 and y = 0.339 at 1670 cd / m < 2 >

Experimental Example 2

The ITO layer was patterned to have a light emitting area of 3 mm x 3 mm on the substrate and then cleaned. A light emitting layer (200 Å) doped with 5% of a dopant represented by RD-1 represented by the above Chemical Formulas 1-4 to a red phosphorescent host material represented by RH-003 in the above Chemical Formula 4, Cuq (650 Å), NPD (350 Å), LiF (5 Å), and Al (1000 Å).

(5.5 V) at 0.9 mA, where CIE x = 0.659, y = 0.338.

Experimental Example 3

The ITO layer was patterned to have a light emitting area of 3 mm x 3 mm on the substrate and then cleaned. A light emitting layer (200 Å) doped with 5% of a dopant represented by RD-1 represented by the above Chemical Formulas 1-4 to a red phosphorescent host material represented by RH-006 in Chemical Formula 4, Alq3 (350 Å), LiF (5 Å), and Al (1000 Å).

(5.3 V) at 0.9 mA, and CIE x = 0.658 and y = 0.340, respectively.

Experimental Example 4

The ITO layer was patterned to have a light emitting area of 3 mm x 3 mm on the substrate and then cleaned. A light emitting layer (200 Å) prepared by adding 5% of a dopant represented by RD-1 in the above formula (1-4) to a red phosphorescent host material represented by RH-019 in formula (4), Alq3 (350 Å), LiF (5 Å), and Al (1000 Å).

(5.5 V) at 0.9 mA and CIE x = 0.658 and y = 0.339, respectively.

Experimental Example 5

The ITO layer was patterned to have a light emitting area of 3 mm x 3 mm on the substrate and then cleaned. The ITO layer PEDOT: PSS (800 Å, spin coating: 3000 rpm, baking condition: 120 ° C for 1 hr) and the red phosphorescent host material represented by RH-003 in the above formula 4 were doped with a dopant represented by RD- (250 Å, 3000 rpm, baking condition: 100 캜 for 30 min) containing 2% of Alq 3 (350 Å), LiF (5 Å) and Al (1000 Å).

(6.5 V) at 0.9 mA and CIE x = 0.658 and y = 0.340, respectively.

Comparative Example 1

The ITO layer was patterned to have a light emitting area of 3 mm x 3 mm on the substrate and then cleaned. A light emitting layer (200 Å), Alq3 (350 Å) and LiF (1 Å) doped with 5% of a dopant represented by RD-1 in the above Chemical Formulas 1-4 to CBP represented by Chemical Formula 1-3, (5 angstroms), and Al (1000 angstroms).

(7.5 V) at 0.9 mA and CIE x = 0.651 and y = 0.329, respectively.

The comparison results of the above-described Experimental Examples 1 to 5 and Comparative Example 1 are shown in Table 1 below. Here, the unit of voltage is V, the unit of current is mA, the unit of luminance is cd / m2, the unit of current efficiency is cd / A, and the unit of power efficiency is lm / W.

Voltage electric current Luminance Current efficiency Power efficiency CIE (X) CIE (Y) Example 1 5.4 0.9 1670 16.7 9.7 0.658 0.339 Example 2 5.5 0.9 1780 17.8 10.1 0.659 0.338 Example 3 5.3 0.9 1752 17.5 10.4 0.658 0.340 Example 4 5.5 0.9 1724 17.2 9.3 0.658 0.339 Example 5 6.5 0.9 1593 15.9 9.1 0.658 0.340 Comparative Example 7.5 0.9 780 7.8 3.3 0.659 0.329

As can be seen from Table 1, in Experimental Examples 1 to 5, the current efficiency is excellent and the power consumption is reduced because light of high luminance is emitted at a low driving voltage.

Particularly, in Experimental Example 5, a luminescent layer is formed by a coating method in a liquid phase and has an excellent effect on a driving voltage, a luminance, and the like. Accordingly, the red phosphorescent host material of the present invention can be manufactured into a large-area device by a coating method.

- Second Embodiment -

The red phosphorescent host material according to the second embodiment of the present invention is characterized in that the 3,4 benzo carbazole is bonded to the meta position and the nitrogen of the carbazole is substituted with a material selected from an aromatic group, And has the following formula (5).

Formula 5

Wherein each of Ar1 and Ar2 is selected from a substituted or unsubstituted aromatic group material, a substituted or unsubstituted aliphatic ring group material, or a substituted or unsubstituted aromatic group material. When Ar1 and Ar2 are the same, they have a symmetrical structure. On the other hand, when Ar1 and Ar2 are different, they have an asymmetric structure.

For example, the aromatic group material may include phenyl, naphthyl, biphenyl, terphenyl, and phenanthrenyl.

The modified ring group material may be at least one selected from the group consisting of pyridinyl, bipyridinyl, quinolinyl, isoquinolinyl, quinoxalinyl, terpyridinyl, It is characterized by containing phenanthrolinyl.

In addition, the aliphatic group material is characterized by containing C1 to C20 aryl and C1 to C20 alkyl.

The aromatic group material, the aliphatic group material, and the aromatic group material may be substituted by C1-C20 aryl, C1-C20 alkyl, C1-C20 alkoxy, halogen, ), Cyano, and silyl. For example, the substituent may be selected from the group consisting of methyl, ethyl, propyl, isopropyl, t-butyl, methoxy, ethoxy, butoxy butoxy, trimethylsilyl, fluorine, and chlorine.

Such a red phosphorescent host material is characterized in that the 3,4 benzo carbazole of the carbazole is bonded to the meta position and the nitrogen of the carbazole is substituted with a material selected from an aromatic group, . In addition, it has advantages of high brightness and high efficiency.

For example, each of Ar1 and Ar2 may be selected from a plurality of substance groups represented by the following formula (6).

6

According to the selection of Ar1 and Ar2, the red phosphorescent host material of Formula 5 may be any one of a plurality of materials represented by Formula 7 below. Here, for ease of explanation, symbols RH001 to RH308 are assigned to the bottom of each material.

Formula 7

Hereinafter, a red phosphorescent host material for an organic electroluminescence device according to the present invention will be described as an example of a red phosphorescent host material represented by RH-001 in Chemical Formula 7 as an example.

Synthetic example

1. Synthesis of 2-bromo-dihydrobenzo [3,4] carbazole

2-bromo-dihydrobenzo [3,4] carbazole is synthesized according to Scheme 6 below.

Scheme 6

Specifically, β-teralone (25 g, 0.17 mol), 3-bromophenylhydrazinuim chloride (38.2 g, 0.17 mol) and acetic acid are placed in ethanol and refluxed for 1 hour in a two-neck round flask. The temperature is lowered to room temperature, then filtered and the solvent is evaporated. Add zinc chloride (58 g, 0.42 mol) and acetic acid and reflux for 30 minutes. The temperature was lowered to room temperature, the solvent was evaporated, and 2-bromo-dihydrobenzo [3,4] carbazole (35.5 g, yield: 70%) was obtained by precipitation with MC / PE.

2. Synthesis of 2-bromobenzo [3,4] carbazole

2-bromobenzo [3,4] carbazole is synthesized by the following reaction formula 7.

Scheme 7

Specifically, 2-bromodihydrobenzo [3,4] carbazole (20 g, 0.07 mol), 2,3-dichloro-5,6-dicyanobenzoquinone (19.8 g, 0.09 mol) and benzene were placed in a two- Lt; / RTI > Ethyl acetate was added and the solvent was evaporated and purified by silica gel column to obtain 2-bromobenzo [3,4] carbazole (15.9 g, yield: 80%).

3. Synthesis of 2-bromo-9-phenylbenzo [3,4] carbazole

2-bromo-9-phenylbenzo [3,4] carbazole is synthesized by the following reaction formula (8).

Scheme 8

Specifically, 2-bromobenzo [3,4] carbazole (5g, 0.017mol), bromobenzene (4g, 0.025mol), Pd2 (dba) 3 (0.42g, 0.046mol% Bu) 3 (0.14g, 0.069mol%), NaOBu (2.4g, 0.025mol) and toluene, and refluxed at 130 ° C for 6 hours. The solution was cooled to room temperature and extracted with methylene chloride. The solvent was evaporated and purified by silica gel column to obtain 2-bromo-9-phenylbenzo [3,4] carbazole (5 g, yield: 80%).

4. Synthesis of 9-phenybenzo [3,4] carbazole-2-boronic acid

9-phenybenzo [3,4] carbazole-2boronic acid is synthesized by the following reaction formula (9).

Scheme 9

Specifically, 2-bromo-9-phenylbenzo [3,4] carbazole (10 g, 0.026 mol) and 100 mL of ether are added to a two-necked round flask and stirred. The temperature is lowered to -78 ° C with a dry-ice bath, then 2.5M n-BuLi (11.8mL, 0.03mol) is slowly dropped and stirred at room temperature for 1 hour. The temperature is lowered to -78 ° C with a dry-ice bath, then triethylborate (10.1 g, 0.05 mol) is slowly dropped and stirred at room temperature for 4 hours. 100 mL of 2N HCl is added and quenched, and the solvent is evaporated. The resulting crystals were filtered and washed with distilled water and hexane 3-4 times to give 9-phenylbenzo [3,4] carbazole-2-boronic acid acid (6.1 g, yield: 70%).

5. Synthesis of RH-001

The red phosphorescent host material represented by RH-001 in formula (7) is synthesized by the following reaction formula (10).

Scheme 10

Specifically, 2-bromo-9-phenylbenzo [3,4] carbazole (2g, 5.4mmol), 9-phenylbenzo [3,4] carbazole-2-boronic acid (1.8g, 5.4mmol) (PPh3) 4 in THF / H2O (20 mL / 20 mL) and reflux for 8 hours. After confirming the reaction with TLC (Thin-Layer Chromatography), the temperature was lowered to room temperature, extracted with methylene chloride, the solvent was evaporated, and purified by silica gel column to obtain RH-001 (2.2 g, yield: 70%).

Hereinafter, examples 6 to 10 of preparing an organic electroluminescent device using the red phosphorescent host material according to the second embodiment of the present invention, the red phosphorescent host material according to the present invention and the organic electroluminescent material The performance of the light emitting device will be described below.

Experimental Example 6

The ITO layer was patterned to have a light emitting area of 3 mm x 3 mm on the substrate and then cleaned. A light emitting layer (200 Å) prepared by adding 5% of a dopant represented by RD-1 in the above Chemical Formulas 1-4 to a red phosphorescent host material represented by RH-002 in Formula (7), Alq3 (350 Å), LiF (5 Å), and Al (1000 Å).

(5.4V) at 0.9 mA and CIE x = 0.657 and y = 0.339, respectively.

Experimental Example 7

The ITO layer was patterned to have a light emitting area of 3 mm x 3 mm on the substrate and then cleaned. A light emitting layer (200 Å) prepared by adding 5% of a dopant represented by RD-1 in the above Chemical Formulas 1-4 to a red phosphorescent host material represented by RH-003 in Chemical Formula 7, Cuq (650 Å), NPD (350 Å), LiF (5 Å), and Al (1000 Å).

(5.6V) at 0.9 mA and CIE x = 0.659 and y = 0.338, respectively.

Experimental Example 8

The ITO layer was patterned to have a light emitting area of 3 mm x 3 mm on the substrate and then cleaned. A light emitting layer (200 Å) prepared by adding 5% of a dopant represented by RD-1 in the above Chemical Formulas 1-4 to a red phosphorescent host material represented by RH-006 in Chemical Formula 7, Alq3 (350 Å), LiF (5 Å), and Al (1000 Å).

(5.2 V) at 0.9 mA and CIE x = 0.654 and y = 0.342, respectively.

Experimental Example 9

The ITO layer was patterned to have a light emitting area of 3 mm x 3 mm on the substrate and then cleaned. A light emitting layer (200 Å) prepared by adding 5% of a dopant represented by RD-1 in the above Chemical Formulas 1-4 to a red phosphorescent host material represented by RH-019 in Chemical Formula 7, Cuq (650 Å), NPD (350 Å), LiF (5 Å), and Al (1000 Å).

(5.6V) at 0.9 mA and CIE x = 0.658 and y = 0.339, respectively.

Experimental Example 10

The ITO layer was patterned to have a light emitting area of 3 mm x 3 mm on the substrate and then cleaned. The ITO layer PEDOT: PSS (800 Å, spin coating: 3000 rpm, baking condition: 120 ° C. for 1 hr) and the red phosphorescent host material represented by RH-003 in the above formula (7) (250 Å, 3000 rpm, baking condition: 100 캜 for 30 min) containing 2% of Alq 3 (350 Å), LiF (5 Å) and Al (1000 Å).

(6.9 V) at 0.9 mA and CIE x = 0.659 and y = 0.338, respectively.

Comparative Example 2

The ITO layer was patterned to have a light emitting area of 3 mm x 3 mm on the substrate and then cleaned. A light emitting layer (200 Å), Alq3 (350 Å) and LiF (1 Å) doped with 5% of a dopant represented by RD-1 in the above Chemical Formulas 1-4 to CBP represented by Chemical Formula 1-3, (5 angstroms), and Al (1000 angstroms).

(7.5 V) at 0.9 mA and CIE x = 0.651 and y = 0.329, respectively.

The comparison results of the above-described Experimental Examples 6 to 10 and Comparative Example 2 are shown in Table 2 below. Here, the unit of voltage is V, the unit of current is mA, the unit of luminance is cd / m2, the unit of current efficiency is cd / A, and the unit of power efficiency is lm / W.

Voltage electric current Luminance Current efficiency Power efficiency CIE (X) CIE (Y) Example 1 5.4 0.9 1534 15.3 8.9 0.657 0.339 Example 2 5.6 0.9 1866 18.6 10.4 0.659 0.338 Example 3 5.2 0.9 1776 17.7 10.7 0.654 0.342 Example 4 5.6 0.9 1734 17.3 9.7 0.658 0.339 Example 5 6.9 0.9 1623 16.2 7.4 0.659 0.338 Comparative Example 7.5 0.9 780 7.8 3.3 0.659 0.329

As can be seen from Table 2, in Experimental Examples 6 to 10, current efficiency is excellent, and power consumption is reduced because light is emitted with a high luminance at a low driving voltage.

Particularly, in Experimental Example 10, a luminescent layer is formed by a coating method in a liquid phase and has an excellent effect on a driving voltage, a luminance, and the like. Accordingly, the red phosphorescent host material of the present invention can be manufactured into a large-area device by a coating method.

An embodiment of an organic electroluminescent device including the red phosphorescent host material is shown in FIG.

As shown, the organic electroluminescent device includes first and second substrates (not shown) facing each other, and an organic light emitting diode (E) formed between the first and second substrates (not shown) .

The organic light emitting diode E includes a first electrode 110 serving as an anode, a second electrode 130 serving as a cathode, and an organic emission layer 120 formed between the first and second electrodes 110 and 130. [ ).

The first electrode 110 is made of a relatively high work function material such as indium-tin-oxide (ITO), and the second electrode 130 is made of a material having a relatively low work function value, For example, aluminum (Al) or an aluminum alloy (AlNd). In addition, the organic light emitting layer 120 has red, green, and blue organic light emission patterns.

The organic light emitting layer 120 may include a hole injection layer (HTL) 121, a hole transporting layer (HIL) 121, and a hole transporting layer (HIL) 121 sequentially from the first electrode 110 in order to maximize luminous efficiency. An emission layer 122, an emitting material layer (EML) 123, an electron transporting layer 124, and an electron injection layer 125.

Here, the light emitting material layer 123 includes the red phosphorescent host material represented by Formula 2 or Formula 5. The red phosphorescent host material is dissolved in a solvent such as xylene at about 1 to 10 wt% and a dopant is added in an amount of about 1 to 10 wt% to prepare a light emitting material layer solution. The light emitting material layer 123 is formed by coating the light emitting material layer solution. In particular, the red phosphorescent host material of the present invention has excellent solubility in non-polar solvents. If the coating process is performed using a polar solvent, when the solvent is evaporated using a hot plate or the like, the solvent remains and can act as a bond. However, this problem does not occur when a non-polar solvent is used. The light emitting material layer 123 may further include a green and blue light emitting material layer.

The organic electroluminescent device having such a structure has advantages in manufacturing a large-area organic electroluminescent device because the light emitting material layer 123 is formed by coating the light emitting material layer solution. In addition, a high-brightness image can be realized, and the light emission efficiency can be improved, so that low-power driving is possible, and power consumption is reduced.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention as defined in the appended claims. It can be understood that

110: first electrode
120: organic light emitting layer
123: luminescent material layer
130: second electrode

Claims (9)

Wherein each of A1 and A2 is independently selected from the group consisting of pyridinyl, bipyridinyl, quinolinyl, isoquinolinyl, quinoxalinyl, terpyridinyl, , Phenanthrolinyl, and a substituted or unsubstituted aliphatic cyclic group group including phenanthrolinyl.

Wherein Ar1 and Ar2 are each independently selected from the group consisting of pyridinyl, bipyridinyl, quinolinyl, isoquinolinyl, quinoxalinyl, terpyridinyl, , Phenanthrolinyl, and a substituted or unsubstituted aliphatic cyclic group group including phenanthrolinyl.

delete delete delete 3. The method according to claim 1 or 2,
The substituent of the aliphatic cyclic group is selected from the group consisting of C1 to C20 aryl, C1 to C20 alkyl, C1 to C20 alkoxy, halogen, cyano, silyl, Lt; RTI ID = 0.0 > phosphorescent host material. ≪ / RTI >
A first electrode;
A second electrode facing the first electrode;
And a light emitting material layer disposed between the first and second electrodes,
Wherein the light emitting material layer comprises the red phosphorescent host material according to claim 1 or 2.

delete 8. The method of claim 7,
Wherein the red phosphorescent host material is soluble in a non-polar solvent and is formed by a coating process.

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