KR20150027362A - Quinone derivatives and organic light emitting diode device comprising the same - Google Patents

Abstract

The present invention relates to a quinone derivative and an organic electroluminescent diode including the same. According to an embodiment of the present invention, the quinone derivative is denoted by chemical formula 1.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a quinone derivative and an organic electroluminescent device including the quinone derivative.

TECHNICAL FIELD The present invention relates to a quinone derivative and an organic electroluminescent device including the quinone derivative. More particularly, the present invention relates to a quinone derivative and an organic electroluminescent device including the quinone derivative capable of improving luminous efficiency and driving voltage of the organic electroluminescent device .

The image display device that realizes various information on the screen is a core technology of the information communication age and it is becoming thinner, lighter, more portable and higher performance. (LCD), a plasma display panel (PDP), an electro luminescent display (ELD), a field emission display (FED), and an organic light emitting diode (OLED) display device, Organic Light Emitting Diode) have been actively studied.

Among these organic electroluminescent devices, electrons and holes are paired when an electric charge is injected into the organic light emitting layer formed between the anode and the cathode, and then the light is emitted while disappearing. The organic electroluminescent device can be formed not only on a flexible transparent substrate such as a plastic but also can be driven at a lower voltage than a plasma display panel (plasma display panel) or an inorganic electroluminescence (EL) display, It has the advantage of being excellent in color. In particular, an organic electroluminescent device that implements white light is used for various purposes such as a thin light source, a backlight of a liquid crystal display device, or a full color display device employing a color filter.

In developing white organic electroluminescent devices, research and development are proceeding according to each method because it is important not only high efficiency and long life but also color stability due to color purity, current and voltage change, and ease of device manufacturing. There are various structures of white organic electroluminescent devices, and they can be largely divided into a single layer light emitting structure and a multilayer light emitting structure. Of these, a multilayered light-emitting structure in which a fluorescent blue light-emitting layer and a phosphorescent yellow light-emitting layer are tandemized for a long-life white device is mainly adopted.

Specifically, a phosphorescent stack structure in which a first stack using a blue fluorescent element as a light emitting layer and a second stack structure using a yellow-green phosphor element as a light emitting layer are stacked. Such a white organic electroluminescent device is realized by the mixing effect of the blue light emitted from the blue fluorescent element and the yellow light emitted from the yellow phosphor element. Here, a charge generation layer is provided between the first stack and the second stack, which doubles the current efficiency generated in the light emitting layer and smoothes charge distribution. The charge generation layer is a layer for generating charges, that is, electrons and holes, in the inside, doubles the current efficiency generated in the light emitting layer, and smoothly distributes the charge, thereby preventing the drive voltage from rising.

Also, aromatic diamine derivatives are widely known as hole transport materials provided in organic electroluminescent devices. Organic electroluminescent devices using these aromatic diamine derivatives as hole transport materials have problems in that the application voltage is increased to obtain sufficient luminescence brightness, and therefore, the lifetime of the device and power consumption are increased. To solve this problem, a method has been proposed in which an electron acceptor compound such as Lewis acid is doped into the hole injection layer or a separate layer is formed. However, the electron-accepting compounds used in these methods are unstable in handling in the manufacturing process of an organic electroluminescent device, or have insufficient stability such as heat resistance during driving, and have a problem that their service life is shortened. Further, F ₄ TCNQ (tetrafluorodicyanoquinodimethanol), which is a typical electron-accepting compound, has a small molecular weight and is substituted with fluorine, has a high sublimation property, and is likely to diffuse into the device during vacuum deposition, . Known hole-transporting materials have a difficulty in synthesis and purification because they have a large number of substituents having electron-accepting ability in the structure, crystallization in the molecular structure is well performed in the device process, and thermal stability is low in many cases, Resulting in deterioration in efficiency and life.

As described above, further studies are required to improve the efficiency, lifetime, and driving voltage characteristics of the organic electroluminescent device.

The present invention provides a quinone derivative and an organic electroluminescent device including the quinone derivative capable of improving the luminous efficiency and lowering the driving voltage of the organic electroluminescent device.

In order to accomplish the above object, the quinone derivative according to one embodiment of the present invention is represented by the following general formula (1).

[Chemical Formula 1]

In Formula 1,

X is a substituted or unsubstituted alicyclic aromatic compound containing S, N or O,

R ₁ and R ₂ are each independently a substituted or unsubstituted hydrocarbon, a hydrocarbon group having 1 to 12 carbon atoms, a halogen group, a cyano group, an alkoxy group, an arylamine group, an ester group, an amide, an aromatic hydrocarbon, A nitrile group,

Y is any one selected from the compounds represented by the following general formula (2)

(2)

Wherein R ₃ to R ₆ are each independently hydrogen, an alkyl group, or an aryl group, or R ₃ and R ₄ are independently hydrogen, an alkyl group, or an aryl group, and R ₅ and R ₆ are bonded to each other to form a ring .

The LUMO level of the compound represented by Formula 1 is -4.0 to -6.0 eV.

The quinone derivative may be any one selected from the following compounds.

Also, an organic electroluminescent device according to an embodiment of the present invention includes at least a hole functional layer and a light emitting layer between a cathode and an anode, and the hole functional layer includes the quinone derivative do.

And the hole functional layer is at least one of a hole injection layer and a hole buffer layer.

And a hole transporting layer between the first electrode and the light emitting layer, wherein the hole transporting layer is located between the first electrode and the hole transporting layer.

The hole functional layer includes both the hole injection layer and the hole buffer layer, and the hole buffer layer is disposed between the hole injection layer and the hole transport layer.

In addition, an organic electroluminescent device according to an embodiment of the present invention includes a first stack including a blue light emitting layer, a second stack including a yellow light emitting layer, and a second stack formed between the first stack and the second An organic electroluminescent device comprising a charge generating layer disposed between the stacks, wherein the charge generating layer comprises the quinone derivative.

The charge generation layer includes an N-type charge generation layer and a P-type charge generation layer, wherein the P-type charge generation layer includes the quinone derivative.

An organic electroluminescent device having a quinone derivative according to an embodiment of the present invention in a hole injection layer, a hole buffer layer, or a charge generation layer can lower driving voltage, improve luminous efficiency, quantum efficiency, and luminance There is an advantage that can be made.

1 and 2 are views showing an organic electroluminescent device according to a first embodiment of the present invention.
3 is a cross-sectional view illustrating an organic electroluminescent device according to a second embodiment of the present invention.
4 is a graph showing the current density of an organic electroluminescent device manufactured according to Experiment 1 of the present invention.
5 is a graph showing the luminance of an organic electroluminescent device manufactured according to Experiment 1 of the present invention.
6 is a graph showing the current density of an organic electroluminescent device manufactured according to Experiment 2 of the present invention.
7 is a graph showing the luminance of an organic electroluminescent device manufactured according to Experiment 2 of the present invention.

Hereinafter, various embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 and 2 are views showing an organic electroluminescent device according to a first embodiment of the present invention.

1, an organic electroluminescent device 100 according to a first embodiment of the present invention includes an anode 110, a hole functional layer 125, a hole transport layer 130, a light emitting layer 140, an electron transport layer 150 ), An electron injection layer 160, and a cathode 170.

The anode 110 may be any one of indium tin oxide (ITO), indium zinc oxide (IZO), and zinc oxide (ZnO). When the anode 110 is a reflective electrode, the anode 110 may have a reflective layer made of any one of aluminum (Al), silver (Ag), and nickel (Ni) under the layer made of any one of ITO, IZO, .

The hole functional layer 125 may be a hole injecting layer and may function to smoothly inject holes from the anode 110 into the light emitting layer 140. The hole injection layer 120 of this embodiment may be a quinone derivative represented by the following formula (1).

[Chemical Formula 1]

X is a substituted or unsubstituted alicyclic aromatic compound containing S, N or O, R ₁ and R ₂ are each independently selected from substituted or unsubstituted hydrogen, a hydrocarbon group having 1 to 12 carbon atoms, a halogen group, An alkoxy group, an arylamine group, an ester group, an amide, an aromatic hydrocarbon, a dicyclic ring compound, a nitro group or a nitrile group. Y may be any one selected from among compounds represented by the following general formula (2).

(2)

Wherein R ₃ to R ₆ are each independently hydrogen, an alkyl group, or an aryl group, or R ₃ and R ₄ are each independently hydrogen, an alkyl group, or an aryl group, and R ₅ and R ₆ are bonded to each other to form a ring .

The quinone derivative may be selected from any of the compounds shown below.

In the quinone derivative, X may be a LUMO of -4.0 to -6.0 eV by introducing a substituted or unsubstituted heteroaromatic compound containing sulfur, nitrogen, and oxygen into a core and introducing a substituent having an electron- Level material. ≪ / RTI > These quinone derivatives have high thermal stability, do not cause crystallization in the device process, and are excellent in the ability to inject and transport holes, compared with known materials, so that the luminous efficiency is improved, the power efficiency is increased, There is an advantage that an organic electroluminescent device can be provided.

The hole-transporting layer 125 may have a thickness of 1 to 150 nm. If the thickness of the hole functional layer 125 is 1 nm or more, the hole injection characteristics can be prevented from being degraded. If the thickness is 150 nm or less, the thickness of the hole functional layer 125 is too thick, There is an advantage that it is possible to prevent the drive voltage from rising.

The hole transport layer 130 plays a role of facilitating the transport of holes and may be formed by using NPD (N, N-dinaphthyl-N, N'-diphenyl benzidine), TPD (N, N'- N, N'-bis- (phenyl) -benzidine), s-TAD, and MTDATA (4,4 ', 4 "-tris (N-3-methylphenyl-N-phenylamino) -triphenylamine) But it is not limited thereto.

The thickness of the hole transport layer 130 may be 1 to 150 nm. Here, if the thickness of the hole transport layer 130 is 5 nm or more, the hole transport property can be prevented from being lowered. If the thickness is 150 nm or less, the thickness of the hole transport layer 130 is too thick, There is an advantage that the driving voltage can be prevented from rising.

The light emitting layer 140 may emit red (R), green (G), or blue (B) light, and may be formed of a phosphor or a fluorescent material.

When the light emitting layer 140 is red, it includes a host material including CBP (carbazole biphenyl) or mCP (1,3-bis (carbazol-9-yl) wherein the dopant comprises at least one selected from the group consisting of iridium, iridium, PQIr (acac) (bis (1-phenylquinoline) acetylacetonate iridium), PQIr (tris (1-phenylquinoline) iridium) and PtOEP (octaethylporphyrin platinum) Or PBD: Eu (DBM) ₃ (Phen) or Perylene. However, the present invention is not limited thereto.

When the light emitting layer 140 is green, it may be composed of a phosphorescent material including a dopant material including a host material including CBP or mCP and containing Ir (ppy) 3 (fac tris (2-phenylpyridine) iridium) Alternatively, it may be made of a fluorescent material including Alq3 (tris (8-hydroxyquinolino) aluminum), but is not limited thereto.

When the light emitting layer 140 is blue, it may be made of a phosphorescent material including a host material including CBP or mCP and including a dopant material including (4,6-F ₂ ppy) ₂ Irpic, but is not limited to, a fluorescent material including any one selected from the group consisting of spiro-DPVBi, spiro-6P, distyrylbenzene (DSB), distyrylarylene (DSA), PFO polymer, and PPV polymer .

The electron transport layer 150 serves to smooth the transport of electrons and is made of at least one selected from the group consisting of Alq3 (tris (8-hydroxyquinolino) aluminum), PBD, TAZ, spiro-PBD, BAlq, But is not limited thereto.

The thickness of the electron transport layer 150 may be 1 to 50 nm. If the thickness of the electron transporting layer 150 is 1 nm or more, the electron transporting property can be prevented from being degraded. If the thickness is 50 nm or less, the thickness of the electron transporting layer 150 is too thick, There is an advantage that the driving voltage can be prevented from rising.

The electron injection layer 160 serves to smooth the injection of electrons and may include Alq3 (tris (8-hydroxyquinolino) aluminum), PBD, TAZ, spiro-PBD, BAlq or SAlq.

The thickness of the electron injection layer 160 may be 1 to 50 nm. If the thickness of the electron injection layer 160 is 1 nm or more, there is an advantage that the electron injection characteristics can be prevented from being degraded. If the thickness is 50 nm or less, the thickness of the electron injection layer 150 is too thick, There is an advantage that it is possible to prevent the drive voltage from rising.

The cathode 170 is an electron injection electrode and may be made of magnesium (Mg), calcium (Ca), aluminum (Al), silver (Ag), or an alloy thereof having a low work function. Here, the anode 170 may be formed to have a thickness thin enough to transmit light when the organic electroluminescent device is a front or both-side light emitting structure, and when the organic electroluminescent device is a back light emitting structure, It can be formed thick enough.

Referring to FIG. 2, the organic electroluminescent device of the present invention may further include a hole injection layer 120 between the hole-transporting layer 125 and the first electrode 110. At this time, the hole functional layer 125 acts as a hole buffer layer between the hole injection layer 120 and the hole transport layer 130. In FIG. 2, the hole functional layer 125 may be formed of the above-described quinone derivative, and a detailed description thereof has been described above, and thus will not be described.

3 is a cross-sectional view illustrating an organic electroluminescent device according to a second embodiment of the present invention. In the following, description of the same components as those of the first embodiment will be omitted.

3, an organic electroluminescent device 200 according to the present invention includes stacks ST1 and ST2 positioned between an anode 210 and a cathode 310, and a plurality of stacks ST1 and ST2 disposed between the stacks ST1 and ST2. Generation layer (260).

In more detail, the first stack ST1 constitutes one light emitting device unit and includes a blue light emitting layer 240. [ The blue light emitting layer 240 may use the blue light emitting materials described in the first embodiment. The first stack ST1 further includes a hole injection layer 220 and a first hole transport layer 230 between the anode 210 and the blue light emitting layer 240. [ The hole injection layer 220 may function to smoothly inject holes from the anode 210 into the blue light emitting layer 240. The hole injection layer 220 may be formed of cupper phthalocyanine (CuPc), poly (3,4) -ethylenedioxythiophene (PEDOT) But is not limited to, at least one selected from the group consisting of PANI (polyaniline) and NPD (N, N-dinaphthyl-N, N'-diphenyl benzidine).

The first hole transport layer 230 has the same structure as the hole transport layer of the first embodiment described above. The first stack ST1 further includes a first electron transport layer 250 on the blue light emitting layer 240. [ The first electron transporting layer 250 has the same structure as the electron transporting layer of the first embodiment described above. A first stack ST1 including a hole injection layer 220, a first hole transport layer 230, a blue light emitting layer 240, and a first electron transport layer 250 is formed on the anode 210. [

A charge generation layer (CGL) 260 is disposed on the first stack ST1. The charge generation layer 260 may be a PN junction charge generation layer in which an N-type charge generation layer 260N and a P-type charge generation layer 260P are bonded. At this time, the PN junction charge generation layer 260 generates charges or separates them into holes and electrons, and injects charges into the respective light emitting layers. That is, the N-type charge generation layer 260N supplies electrons to the blue light emitting layer 240 adjacent to the anode, and the P-type charge generation layer 260P supplies holes to the light emitting layer of the second stack ST2, The light emitting efficiency of the organic electroluminescent device including the light emitting layer of the light emitting layer can be further increased, and the driving voltage can be lowered.

Here, the P-type charge generation layer 260P may be a quinone derivative represented by the following formula (1).

[Chemical Formula 1]

X is a substituted or unsubstituted alicyclic aromatic compound containing S, N or O, R ₁ and R ₂ are each independently selected from substituted or unsubstituted hydrogen, a hydrocarbon group having 1 to 12 carbon atoms, a halogen group, An alkoxy group, an arylamine group, an ester group, an amide, an aromatic hydrocarbon, a dicyclic ring compound, a nitro group or a nitrile group. Y may be any one selected from among compounds represented by the following general formula (2).

(2)

Wherein R ₃ to R ₆ are each independently hydrogen, an alkyl group, or an aryl group, or R ₃ and R ₄ are each independently hydrogen, an alkyl group, or an aryl group, and R ₅ and R ₆ are bonded to each other to form a ring .

The quinone derivative may be selected from any of the compounds shown below.

The quinone derivative used for the P-type charge generation layer 260P has high thermal stability, does not cause crystallization in the element process, and is excellent in the ability to inject and transport holes, compared with known materials, The organic electroluminescent device is improved in power consumption by inducing the rise of the organic electroluminescent device.

The N-type charge generation layer 260N may be formed of a metal or an N-type doped organic material. The metal may be one selected from the group consisting of Li, Na, K, Rb, Cs, Mg, Ca, Sr, Ba, La, Ce, Sm, Eu, Tb, Dy and Yb. The N-type dopant used for the organic material doped with the N-type material and the host material may be a commonly used material. For example, the N-type dopant may be an alkali metal, an alkali metal compound, an alkaline earth metal, or an alkaline earth metal compound. In detail, the N-type dopant may be selected from the group consisting of Cs, K, Rb, Mg, Na, Ca, Sr, Eu and Yb. The host material may be a material selected from the group consisting of tris (8-hydroxyquinoline) aluminum, triazine, hydroxyquinoline derivatives, and benzazole derivatives and silole derivatives.

On the other hand, a second stack ST2 including a yellow light emitting layer 290 is located on the charge generation layer 260. [ The yellow light emitting layer 290 may have a multilayer structure of a light emitting layer for emitting yellow green or a light emitting layer for emitting green light. In this embodiment, a single layer structure of a yellow light emitting layer for emitting yellow green is described as an example. The yellow light emitting layer 290 may be formed of CBP (4,4'-N, N'-dicarbazolebiphenyl) or Balq (Bis (2-methyl-8-quinlinolato- N1, O8) - (1,1'- aluminum, and a phosphorescent yellow green dopant that emits yellow green to at least one host selected from the group consisting of aluminum, silver, and aluminum.

The second stack ST2 further includes a second hole transport layer 270 and an electron blocking layer 280 between the charge generation layer 260 and the yellow light emitting layer 290. The second hole transport layer 270 has the same structure as the first hole transport layer 230 described above. The electron block layer 280 is formed of a material of the hole transporting layer and a metal or a metal compound so as to prevent electrons generated in the light emitting layer from flowing to the hole transporting layer. Therefore, the LUMO level of the electronic block layer becomes high, and the electrons can not fall over.

The second stack ST2 further includes a second electron transport layer 300 on the yellow light emitting layer 290 and the second electron transport layer 300 includes the first electron transport layer 250). A second stack ST2 including a second hole transport layer 270, an electron blocking layer 280, a yellow light emitting layer 290 and a second electron transport layer 300 is formed on the charge generation layer 260 . A cathode 310 is provided on the second stack ST2 to constitute an organic electroluminescent device according to the second embodiment of the present invention.

Hereinafter, synthesis examples of the quinone derivatives of the present invention and organic electroluminescent devices including the same will be described in the following Synthesis Examples and Examples. However, the following examples are illustrative of the present invention, but the present invention is not limited to the following examples.

Synthetic example

1) Preparation of 2,5-dibromo-N, N-dimethylthiophene-3-carboxamide (2,5-dibromo-N)

Compound S (5.0 g, 32 mmol) was dissolved in 200 ml of dimethylformamide (DMF), 11.5 g (64 mmol) of N-bromosuccinimide was added at room temperature, and the mixture was stirred at room temperature for 12 hours. After the reaction was completed, recrystallization was performed using dichloromethane and methanol to obtain 9.6 g of 2,5-dibromo-N, N-dimethylthiophene-3-carboxamide (yield 95%).

2) Preparation of compound S-2

Compound S-1 (9.0 g, 29 mmol) was dissolved in anhydrous ether (ether, 300 ml) and butyllithium (n-BuLi, 2.5 M solution, 23 ml) was added dropwise at room temperature and stirred at room temperature for 12 hours. The reaction mixture was poured into ice water, the organic layer was extracted with ethyl acetate, dried with anhydrous magnesium sulfate and dried. The obtained reaction product was recrystallized from acetone to obtain 10.9 g of a compound S-2 (yield: 62%).

3) Preparation of compound S-3

Compound S-2 (5g, 13mmol) the words furnace nitriles (malononitrile) 1.75g (26mmol) and pyridine (pyridine) 10mL, and then chloroform (chloroform) into a 200mL mixture was stirred at room temperature, titanium tetrachloride (TiCl ₄₎ 5mL Was slowly added and the reaction mixture was heated and stirred for 5 hours. The reaction mixture was warmed to room temperature, extracted with dichloromethane (CH ₂ Cl ₂ ) and water (H ₂ O), and the organic dichloromethane solvent was dried with anhydrous sodium sulfate. The obtained reaction product was recrystallized from dichloromethane and acetonitrile to obtain 2.82 g of a compound S-3 (yield: 45%).

4) Preparation of compound S-4

The compound S-3 (2.0 g, 4.2 mmol) was dissolved in 100 ml of tetrahydrofuran (THF), and 0.95 g (8.4 mmol) of copper cyanide (CuCN) and tetrakis (triphenylphosphine) palladium (PPh ₃ ) ₄ ) was added and refluxed at 70 ° C for 24 hours. When the reaction was completed, recrystallization was performed using dichloromethane and methanol to obtain 0.54 g of the compound S-4 (yield: 35%).

5) Preparation of compound S-5

Compound S-3 (2.0 g, 4.2 mmol) was dissolved in 300 ml of DMF, and then pentafluorophenylboronic acid (0.98 g, 4.6 mmol), tris (dibenzylideneacetone) ) dipalladium (192 mg, 0.21 mmol), cesium fluoride (1.27 g, 8.4 mmol), silver (I) oxide (1.17 g, 5.04 mmol) Tri-tert-butylphosphine (0.1 g, 0.50 mmol) was added and stirred at 100 占 폚 for 12 hours. After the reaction was completed, the solution was filtered through Celite, extracted with ethyl acetate, and dried with anhydrous magnesium sulfate. The obtained reaction product was purified through a column to obtain 1.2 g of S-5 compound. (Yield: 44%)

6) Preparation of compound S-6

Compound S-2 (2.0 g, 5.3 mmol) was dissolved in 300 ml of DMF, and phenylboronic acid (0.71 g, 5.83 mmol), tris (dibenzylideneacetone) dipalladium, (1.47 g, 6.4 mmol) and tri-tert-butylphosphine (0.24 g, 0.27 mmol), cesium fluoride (1.61 g, 10.6 mmol), silver (I) oxide Tri-tert-butylphosphine (0.13 g, 0.64 mmol) was added and stirred at 100 < 0 > C for 12 h. After the reaction was completed, the solution was filtered through celite, extracted with ethyl acetate, and dried with anhydrous magnesium sulfate. The obtained reaction product was purified through a column to obtain 1.5 g of S-5 compound. (Yield: 76%)

7) Preparation of compound S-7

Compound S-6 (1.0 g, 2.68 mmol) was dissolved in 150 ml of dichloromethane (CH ₂ Cl ₂ )

4- (cyanomethyl) -2,3,5,6-tetrafluorobenzonitrile (1.15 g, 5.36 mmol) was added thereto, followed by stirring at room temperature , Titanium chloride (TiCl 4) (0.73 mL, 6.7 mmol) and pyridine (1.08 mL, 13.4 mmol) were gradually added at 0 ° C and the mixture was refluxed for 12 hours. After the reaction was completed, the reaction mixture was recrystallized from dichloromethane and ethyl acetate, and then subjected to column chromatography to obtain 0.7 g of S-7 compound (yield: 34%).

Experiments for fabricating an organic electroluminescent device using the quinone derivative S-4 of the present invention prepared in the above-mentioned Synthesis Example as a hole injection layer and a hole buffer layer are described below.

Experiment 1: Quinone derivatives used in the hole injection layer

≪ Example 1 >

The ITO glass was patterned to have a light emitting area of 3 mm x 3 mm and then cleaned. After the substrate was mounted in a vacuum chamber, the base material was made to have a pressure of 1 x 10 ^-6 torr. Then, an organic material was formed on ITO as a hole injection layer and a compound S-4 was formed to a thickness of 30 Å. As the hole transport layer, α- Doped YG-D doped with 10% doping concentration to form a 300 Å thick hole blocking layer, a 50 Å thick BCP as a hole blocking layer, and an electron transport layer Alq ₃ was formed to a thickness of 150 angstroms, LiF was formed to a thickness of 5 angstroms as an electron injecting layer, and Al was sequentially formed to a thickness of 1000 angstroms to form an organic electroluminescent device.

≪ Example 2 >

An organic electroluminescent device was fabricated under the same process conditions as in Example 1 except that the compound S-5 was used as the hole injection layer.

≪ Example 3 >

An organic electroluminescent device was fabricated under the same process conditions as in Example 1 except that the compound S-7 was used as the hole injection layer.

≪ Comparative Example 1 &

An organic electroluminescent device was fabricated under the same process conditions as in Example 1 except that only HAT-CN conventionally used as a hole injection layer was used.

The driving voltage, the luminous efficiency, the quantum efficiency, the luminance, and the color coordinate of the organic electroluminescent device manufactured according to the above-described Examples 1 to 3 and Comparative Example 1 were measured and shown in Table 1 below. The current density and the luminance were measured, 4 and 5.

#
Driving voltage
(V) Luminous efficiency Quantum efficiency
(%) Luminance
(Cd / m 2) Color coordinates Cd / A lm / W CIE_x CIE_y Comparative Example 1 5.82 45.29 24.43 16.86 4529 0.449 0.538 Example 1 4.33 62.17 44.01 21.18 6217 0.419 0.565 Example 2 4.42 61.80 43.97 21.08 6180 0.419 0.565 Example 3 4.44 57.38 41.66 19.66 5738 0.419 0.565

Referring to Table 1, FIG. 4, and FIG. 5, Examples 1 to 3 using the quinone derivative of the present invention as a hole injection layer showed lower driving voltage and improved luminous efficiency, Brightness and color coordinates are improved.

Experiment 2: Quinone derivatives used in the hole buffer layer

<Example 4>

Except that HAT-CN was used as the hole injecting layer and the hole blocking layer was formed between the hole injecting layer and the hole transporting layer and the compound S-4 was formed to a thickness of 120 Å under the same process conditions as in Example 1 described above, The device was fabricated.

&Lt; Example 5 >

An organic electroluminescent device was fabricated under the same process conditions as in Example 4 except that the compound S-5 was used as the hole buffer layer.

&Lt; Comparative Example 2 &

An organic electroluminescent device was fabricated under the same process conditions as in Comparative Example 4 except that HAT-CN conventionally used as a hole injection layer was used.

The driving voltage, the luminous efficiency, the quantum efficiency, the luminance and the chromaticity coordinates of the organic electroluminescent device manufactured according to the above-described Examples 4 and 5 and Comparative Example 2 were measured and shown in the following Table 2, and the current density and the luminance are shown in FIGS. 7.

#
Driving voltage
(V) Luminous efficiency Quantum efficiency
(%) Luminance
(Cd / m 2) Color coordinates Cd / A lm / W CIE_x CIE_y Comparative Example 2 5.82 45.29 24.43 16.86 4529 0.449 0.538 Example 4 3.63 65.33 56.47 22.81 6533 0.435 0.552 Example 5 4.04 62.31 48.46 22.07 6231 0.443 0.545

Referring to Tables 2, 6 and 7, in the case of Examples 4 and 5 in which the quinone derivative of the present invention was used as a hole buffer layer between the hole injection layer and the hole transport layer, compared with Comparative Example 2 without the hole buffer layer It was confirmed that the driving voltage was decreased and the luminous efficiency, the quantum efficiency and the luminance were improved.

As described above, the organic electroluminescent device comprising the quinone derivative according to the present invention in the hole injection layer, the hole buffer layer, or the charge generation layer has lower driving voltage than the conventional organic electroluminescent device, And the brightness can be improved.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be understood that the invention may be practiced. It is therefore to be understood that the embodiments described above are to be considered in all respects only as illustrative and not restrictive. In addition, the scope of the present invention is indicated by the following claims rather than the detailed description. Also, all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included within the scope of the present invention.

100: organic electroluminescent device 110: anode
125: hole-functioning layer 130: hole-transporting layer
140: light emitting layer 150: electron transporting layer
160: electron injection layer 170: cathode

Claims (9)

A quinone derivative represented by the following formula (1).
[Chemical Formula 1]

In Formula 1,
X is a substituted or unsubstituted alicyclic aromatic compound containing S, N or O,
R ₁ and R ₂ are each independently a substituted or unsubstituted hydrocarbon, a hydrocarbon group having 1 to 12 carbon atoms, a halogen group, a cyano group, an alkoxy group, an arylamine group, an ester group, an amide, an aromatic hydrocarbon, A nitrile group,
Y is any one selected from the compounds represented by the following general formula (2)
(2)

Wherein R ₃ to R ₆ are each independently hydrogen, an alkyl group, or an aryl group, or R ₃ and R ₄ are independently hydrogen, an alkyl group, or an aryl group, and R ₅ and R ₆ are bonded to each other to form a ring .
The method according to claim 1,
Wherein the LUMO level of the compound represented by Formula 1 is -4.0 to -6.0 eV.
The method according to claim 1,
Wherein the quinone derivative is any one selected from the compounds shown below.

An organic electroluminescent device comprising at least a hole-transporting functional layer and a light-emitting layer between an anode and a cathode,
Wherein the hole-transporting layer comprises the quinone derivative according to any one of claims 1 to 3.
5. The method of claim 4,
Wherein the hole functional layer is at least one of a hole injection layer and a hole buffer layer.
5. The method of claim 4,
The organic electroluminescent device of claim 1, further comprising the hole transport layer between the first electrode and the light emitting layer, wherein the hole functional layer is positioned between the first electrode and the hole transport layer.
The method according to claim 6,
Wherein the hole functional layer includes both the hole injection layer and the hole buffer layer, and the hole buffer layer is disposed between the hole injection layer and the hole transport layer.
An organic electroluminescent element formed between the anode and the cathode and including a first stack including a blue light emitting layer, a second stack including a yellow light emitting layer, and a charge generating layer located between the first stack and the second stack, In this case,
Wherein the charge generation layer comprises the quinone derivative according to any one of claims 1 to 3.
9. The method of claim 8,
Wherein the charge generation layer comprises an N-type charge generation layer and a P-type charge generation layer, and the P-type charge generation layer comprises the quinone derivative.

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