KR20130067177A - Compound and organic light emitting diode device using the same - Google Patents

Abstract

여기서, 상기 X, Y 및 Z 중 적어도 어느 하나는 질소로 이루어지고,
상기 R1은 치환되거나 치환되지 않은 방향족 화합물과 헤테로 방향족 화합물 및 실리콘 화합물에서 선택되고,
상기 R2 및 R3는 각각 독립적으로 치환되거나 치환되지 않은 방향족 화합물과 헤테로 방향족 화합물, 수소, 중수소, 실리콘 화합물 및 포스포릴(phoshporyl)에서 선택한다.The present invention relates to a compound represented by the following formula (1) or an organic light emitting device using the same.
[Formula 1]

Here, at least one of the X, Y and Z is made of nitrogen,
R 1 is selected from a substituted or unsubstituted aromatic compound, a heteroaromatic compound, and a silicon compound,
R 2 and R 3 are each independently selected from a substituted or unsubstituted aromatic compound and a heteroaromatic compound, hydrogen, deuterium, a silicon compound, and phosphoryl.

Description

Compound and organic light emitting diode device using the same

The present invention relates to an organic light emitting display device, and more particularly, to a compound capable of improving lifespan and luminous efficiency, and an organic light emitting display device using the same.

Today, display devices have been rapidly developed with the development of information and communication. In particular, the organic light emitting display device of the display device is a self-light emitting device, and does not have to be provided with a separate backlight unit, and thus may be formed thinner than other display devices and may have low power consumption.

Here, the organic light emitting diode includes an anode electrode, a cathode electrode and a light emitting layer provided between the anode electrode and the cathode electrode. Here, the anode electrode provides holes to the light emitting layer, and the cathode electrode provides electrons to the light emitting layer. In this case, excitons are generated through recombination of electrons and holes in the emission layer, and the excitons fall to the ground state to emit light.

Here, the exciton may have a ratio of the singlet and triplet is 1: 3. In this case, in the case of fluorescence, light is emitted using only the excitons of the singlet, and in the case of phosphorescence, light is emitted using both the excitons of the singlet and triplet. Accordingly, when the organic electroluminescent device uses a phosphorescent material rather than fluorescence, high luminous efficiency can be obtained. As described above, since the phosphorescent material may have a very high quantum efficiency as compared with the fluorescent material, the luminous efficiency of the organic EL device can be increased, and much research has been made.

Meanwhile, the phosphorescent material may include a host material and a phosphorescent dopant material which emits light by transferring energy therefrom. This is because when the phosphorescent material is used alone as a phosphorescent dopant, the luminous efficiency is drastically reduced due to the quenching phenomenon. At this time, the triplet energy level of the host material must be sufficiently larger than the triplet energy level of the phosphor, so that the transition phenomenon can occur without the reverse energy transfer in the energy transfer process. In other words, when the triplet energy level of the host material is greater than the triplet energy level of the phosphor, the quantum efficiency can be maximized.

However, the triplet energy level of the conventional host material is smaller than the triplet energy level of the phosphorescent dopant, thereby limiting the improvement of the quantum efficiency.

As the conventional host material has a low glass transition temperature, there is a problem that the life of the device is shortened due to the deformation of the material at a high temperature or a driving temperature due to the thermal stability of the material.

Therefore, in order to improve the luminous efficiency and lifetime of the organic light emitting display device, it is urgent to develop a new host material.

The present invention is to solve the problems that may occur in the organic light emitting device, and in particular, an object of the present invention to provide a compound and an organic light emitting device using the same that can improve the luminous efficiency and lifetime.

One compound of one solution according to the invention is provided. Compounds according to the invention can be represented by the following formula (1).

Herein, at least one of X, Y and Z is made of nitrogen, and R1 is selected from a substituted or unsubstituted aromatic compound, a heteroaromatic compound and a silicon compound, and R2 and R3 are each independently substituted or substituted Non-aromatic compounds and heteroaromatic compounds, hydrogen, deuterium, silicone compounds and phosphoryls.

Provided are an organic light emitting display device according to another solution according to the present invention. The organic light emitting device according to the present invention includes an organic light emitting device including a light emitting layer between an anode and a cathode, wherein the light emitting layer includes a dopant material and a host material, and the host material may be represented by the following Chemical Formula 1.

[Formula 1]

Herein, at least one of X, Y and Z is made of nitrogen, and R1 is selected from a substituted or unsubstituted aromatic compound, a heteroaromatic compound and a silicon compound, and R2 and R3 are each independently substituted or substituted Non-aromatic compounds and heteroaromatic compounds, hydrogen, deuterium, silicone compounds and phosphoryls.

The organic electroluminescent device according to the embodiment of the present invention can achieve high efficiency and long life by using a novel compound.

1 is a cross-sectional view of an organic light emitting display device according to an embodiment of the present invention.
2 is a graph showing the UV spectrum, the room temperature PL spectrum and the PL spectrum at low temperature of the compound according to the experimental example of the present invention.

Hereinafter, the compound according to the first embodiment of the present invention will be described in detail.

Compounds according to the invention can be represented by the following formula (1).

[Formula 1]

Herein, at least one of X, Y and Z is made of nitrogen, and R1 is selected from a substituted or unsubstituted aromatic compound, a heteroaromatic compound and a silicon compound, and R2 and R3 are each independently substituted or substituted Non-aromatic compounds and heteroaromatic compounds, hydrogen, deuterium, silicone compounds and phosphoryls.

Specifically, X is nitrogen, and Y and Z are alpha-carboline groups each consisting of carbon, Y is nitrogen, and X and Z are each beta carboline consisting of carbon (β-carboline). ) And Z is nitrogen, and X and Y may each be selected from a gamma carboline group consisting of carbon. Here, all of the carboxyl groups can be the same or different.

In addition, the R1 is phenyl, dibenzothiphene, diphenfuran, dibenzofuran, tetraphenylsilane, pyridine, quinolin, isoquinoline, isoquinoline, pyri It may be selected from the group consisting of pyrimidine and their substituents. Alternatively, the substituent of R1 may be selected from the group consisting of alpha carboline group, beta carboline group, gamma carboline group, fluorene and fluorene.

Alternatively, the substituent of R1 may be selected from the group consisting of Formulas A1 to A9.

R2 and R3 are each independently hydrogen, phenyl, triphenylsilane, tetraphenylsilane, pyridine, quinolin, isoquinoline, pyrimidine ) And their substituents.

Here, specific examples of the compound represented by Formula 1 may be represented by any one of the following Formulas B1 to B17. However, the embodiment of the present invention is not limited thereto.

Here, the compound represented by Formula 1 may have a triplet energy level higher than that of conventional bis (N-carbozolyl) biphenyl) Bis (N-carbazolyl) biphenyl; CBP as it has a carboline group. Accordingly, when the compound represented by Chemical Formula 1 is used as the host material of the light emitting layer, it is possible to prevent the reverse energy transfer phenomenon from the host to the dopant, thereby preventing the luminous efficiency, particularly at low temperature, from being lowered.

In addition, since the difference between the triplet energy level and the singlet energy level can be reduced compared to the prior art, the luminous efficiency and voltage characteristics can be increased when fabricating the organic light emitting device.

Compound represented by Formula 1 has a higher glass transition temperature than conventional bis (N- carbozolyl) biphenyl) Bis (N-carbazolyl) biphenyl (CBP), thereby improving the lifespan during fabrication of the organic light emitting device You can.

As the compound represented by Chemical Formula 1 has a bipolarity, it is possible to reduce the deviation of electrons or holes in the light emitting layer, thereby increasing the lifespan and luminous efficiency during fabrication of the organic light emitting device.

In addition, the compound represented by Formula 1 may be used as a material for forming a hole blocking layer and an electron transport layer.

Hereinafter, with reference to the drawings of the organic light emitting device will be described in detail. The following embodiments are provided by way of example so that those skilled in the art can fully understand the spirit of the present invention.

Therefore, the present invention is not limited to the embodiments described below, but may be embodied in other forms. In the drawings, the size and thickness of an apparatus may be exaggerated for convenience. Like numbers refer to like elements throughout.

1 is a cross-sectional view of an organic light emitting display device according to a second exemplary embodiment of the present invention.

Referring to FIG. 1, an organic light emitting display device 100 according to an exemplary embodiment of the present invention may include an anode 120, a light emitting layer 150, and a cathode 190 sequentially disposed on a substrate 110. .

Here, an example of a material that may be used as the substrate 110 may be glass or resin. When the substrate 110 is formed of a resin, the resin may be selected as a material having a smaller moisture or oxygen transmittance as the light emitting layer 150 than other materials. Examples of the resin may be polycarbonate, polyimide, polyethylene terephthalate, polyethylene naphthalate, or the like. The substrate 110 may be rigid or flexible.

The anode 120 is disposed on the substrate 110. The anode 120 may be made of a transparent conductive material. An example of a material for forming the anode 120 may be ITO or IZO.

The light emitting layer 150 may be disposed on the anode 120. Here, the light emitting layer 150 may be formed of a material emitting green or blue light.

When the light emitting layer 150 emits blue light, the light emitting layer 150 may include a blue phosphorescent dopant and a blue phosphorescent host material doped with the blue phosphorescent dopant.

Here, as an example of the blue phosphorescent dopant, the compound represented by the following Chemical Formula 2 or Chemical Formula 3 may be selected. However, in the embodiment of the present invention, the material of the blue phosphorescent dopant is not limited.

In addition, the blue phosphorescent host material may be a compound represented by Chemical Formula 1.

Here, the blue phosphorescent dopant may be doped at 0.1 to 50% by weight based on the total weight of the blue phosphorescent host material and the blue phosphorescent dopant. Here, when the blue phosphorescent compound is doped at less than 0.1% by weight, the energy conversion efficiency may be reduced. On the other hand, when the blue phosphorescent compound exceeds 50% by weight, the luminous efficiency and lifespan may decrease due to the occurrence of quenching between the phosphors.

In the exemplary embodiment of the present invention, the organic light emitting layer 140 has been described as being a blue light emitting layer, but in order to substantially realize full color, the organic light emitting layer 140 may be patterned for each region, and in addition to the blue light emitting layer, It may further include a red light emitting layer. In this case, the blue light emitting layer, the green light emitting layer, and the red light emitting layer may form one pixel to express various grayscales. Examples of constituting the green light emitting layer may include a host tris-8-hydroxyquinoline aluminum (Alq3) and a green phosphorescent dopant N-methylquinacridone (MQD). have. In addition, the thickness of the green light emitting layer may be formed to a thickness of 300Å. In addition, examples of constituting the red light emitting layer include 4,4'-biscarbazolylbiphenyl (4,4'-N, N'-dicarbazole-biphenyl; CBP), which is a host, and bis (2-phenylquinolin) acetylaceto, which is a dopant. -Nate) iridium (bis (2-phenylquinoline) (acetylacetonate) iridium; Ir (Phq) 2 (acac)).

The organic light emitting layer 150 may be formed through a vacuum deposition method.

Here, the host material of the green light emitting layer is described as being formed of tris-8-hydroxyquinoline aluminum (Alq3), but is not limited thereto, and the host material of the green light emitting layer is represented by Chemical Formula 1 above. The compound shown can also be used. In this case, the blue light emitting layer and the green light emitting layer may be formed of the same host material.

The cathode 190 is disposed on the light emitting layer 150. The cathode 190 may be made of a reflective conductive material. Examples of the material for forming the cathode 190 may be made of a single metal of any one of Al, Ag, Cr, Au, W, and Ti, or an alloy including any one. However, the embodiment of the present invention does not limit the material of the cathode 190.

In addition, the organic light emitting diode 100 may include any one or both of the hole injection layer 130 and the hole transport layer 140 disposed between the anode 120 and the light emitting layer 150.

Here, the hole injection layer 130 may be disposed on the anode 120. In this case, the hole injection layer 130 may serve to help release holes from the anode 120. Examples of the material for forming the hole injection layer include 4,4'-bis [N- [4- {N, N-bis (3-methylphenyl) amino} phenyl-N-phenylamino] biphenyl (4,4'-bis [4- {N, N-bis (3-methylphenyl) amino} phenyl} -N-phenylamino] biphenyl; DNTPD). Here, the hole injection layer may be formed through a vacuum deposition method. At this time, the material of the hole injection layer is not limited, and as another example, 4,4 ', 4 "-tris (3-methylphenyl-N-phenylamino) triphenylamine) ([4,4,4" -tris (3 -methylphenylphenylamino) triphenylamine]; m-MTDATA) and copper phthalocyanine (CuPc).

The hole transport layer 140 may play a role of smoothly transporting from the anode 120 to the light emitting layer 150. Here, the hole transport layer 140 may further play a role of preventing electrons from escaping from the light emitting layer 150. The hole transport layer is N, N-bis (naphthalen-1-yl) phenyl-N, N-bis (phenyl) benzidine (N, N'-bis (naphthalene-1-yl) -N, N'-biss (phenyl) -benzidine; NPB).

In this case, when the hole injection layer 130 and the hole transport layer 140 are both provided, the hole injection layer 130 and the hole transport layer 140 may be sequentially stacked on the anode 120.

In addition, the organic light emitting diode 100 may include any one or both of the hole blocking layer 160, the electron transport layer 170, and the electron injection layer 180 disposed between the light emitting layer 150 and the cathode 190. It may include.

Here, the hole blocking layer 160 may serve to prevent holes from escaping from the organic light emitting layer 150. Examples of the material for forming the hole blocking layer 160 include aluminum (III) bis (2-methyl-8-quitolinato) -4-phenylphenolate (Aluminum (III) bis (2-methyl-8-quinolinato)- 4-phenylphenolate; BAlq).

The electron transport layer 170 may serve to transport electrons emitted from the cathode 190 to the emission layer 150. Here, the electron transport layer 170 may further play a role of preventing holes from leaving the light emitting layer 150 to the cathode 190. Examples of the material for forming the electron transport layer 160 include tris (8-hydroxyquinolinato aluminum; Alq3) and (2- (4-biphenyl) -5- (4-tert-butyl Phenyl) -1,3,4-oxadiazole) (2- (4-biphenyl) -5- (4-tert-butylphenyl) -1,3,4-oxadiazole; PBD) and the like.

The electron injection layer 180 may serve to help release electrons from the cathode 190. Here, an example of a material for forming the electron injection layer 180 may be lithium fluoride (LiF).

As in the exemplary embodiment of the present invention, the organic light emitting diode 100 may include the hole and electron injection layers 120 and 180, the hole blocking layer 160, the hole and electron transport layers 130 and 170 in addition to the light emitting layer 150. By further including at least one, it is possible to improve the luminous efficiency and lifetime of the organic light emitting device.

Here, at least one of the hole blocking layer 160 and the electron transport layer 170 may be made of a compound represented by Chemical Formula 1 having excellent thermal stability.

In addition, although not shown in the drawing, the anode 120, the light emitting layer 150, and the cathode 190 may further include a sealing member for sealing from the outside. This is because the light emitting layer 150 may be easily degraded by external moisture or oxygen. The sealing member may be an upper substrate bonded to the substrate with the anode 120, the light emitting layer 150, and the cathode 190 interposed therebetween. Alternatively, the sealing member may be an inorganic insulating layer covering the substrate 110 including the anode 120, the light emitting layer 150, and the cathode 190.

Therefore, as in the embodiment of the present invention, the organic light emitting device includes a novel host material having a triplet energy higher than that of the prior art, thereby increasing the luminous efficiency of the organic light emitting device.

In addition, since the new host material has a higher glass transition temperature than the conventional one, it is possible to prevent deformation of the host material due to heat at a high temperature or a driving temperature, thereby improving the lifetime of the organic light emitting device. have.

In addition, as the novel host material has bipolarity, the luminous efficiency and lifespan of the organic light emitting display device can be increased.

Hereinafter, a method of preparing a host material according to the present invention will be described in detail with reference to the following experimental examples. Through the following experimental example is only for illustrating the present invention is not limited thereto.

Experimental Example  1: 3,6-di (alpha Kaboline ) -9- (4-(( Triphenyl Silly) Phenyl ) Carbazole (3,6-di (α- carboline ) -9- (4- ( 트리 피닐 ) silylphenly ) carbazole ) Synthesis of

1-iodine- (4- (triphenyl) silyl) phenyl (1-iodine- (4- (triphenyl) silylphenly) 3.24 mmol, 3,6-di (alpha carboline) carbazole (3,6) -di (α-carboline) carbazole) 3.24 mmol, K ₃ PO ₄ 6.5 mmol, CuI 0.97 mmol, trans-1,2-cyclohexanediamine 0.97 mmol, 1,4-dioxane 50 ml of (1,4-dioxane) was added and refluxed under a nitrogen atmosphere for 24 hours, and after completion of the reaction, 1,4-dioxane was removed by distillation under reduced pressure. After extraction with water, distillation under reduced pressure, silica gel column, and then the solvent was distilled under reduced pressure, and then recrystallized and filtered using dichloromethane and petrolium ether. 1.0 g of, 6-di (alpha carboline) -9- (4-((triphenyl) silyl) phenyl) carbazole was obtained.

The synthesis mechanism of 3,6-di (alpha carboline) -9- (4-((triphenyl) silyl) phenyl) carbazole can be represented by Scheme 1 below.

[ Scheme 1]

2 and Table 1 show the experimental results of the compound prepared in Experimental Example 1.

Figure 2 is a graph showing the UV spectrum, room temperature PL spectrum and low temperature PL spectrum of the compound according to the preparation of the present invention. Here, the low temperature was 77K.

ingredient Tg
(℃) HOMO ^a
(eV) LUMO
(eV) Band gap Energy (eV) ^b △ E _st E _T
(eV) ^c Comparative example 62 6.3 2.8 3.5 0.9 2.6 Experimental Example 1 113 5.82 2.53 3.29 0.38 2.91

Here, the comparative example in Table 1 is J. Appl . Phys . 2001.90,5048 and bis (N-carbozolyl) biphenyl) Bis (N-carbazolyl) biphenyl; CBP).

HOMO was measured by AC-2 (Photo-electron spectrometer, RIKEN KEIKI CO., LTD).

Band gap energy was measured from UV absorption onset.

E _T was dissolved in 2-methyl THF and measured for exicitation using PL maxima for 300 nm.

As shown in FIG. 2 and Table 1, 3,6-di (alpha carboline) -9- (4-((triphenyl) silyl) phenyl) carbazole prepared by Experimental Example 1 was higher than that of the prior art. It was confirmed that the glass transition temperature.

The 3,6-di (alpha carboline) -9- (4-((triphenyl) silyl) phenyl) carbazole prepared by Experimental Example 1 has a higher triplet energy level compared to the conventional CBP. there was.

In addition, the 3,6-di (alpha carboline) -9- (4-((triphenyl) silyl) phenyl) carbazole prepared by Experimental Example 1 has triplet energy level and singlet energy as compared to the conventional CBP. It was confirmed that the difference in level is small. Accordingly, the 3,6-di (alpha carboline) -9- (4-((triphenyl) silyl) phenyl) carbazole prepared in Experimental Example 1 has a lower barrier to entry of charge into the light emitting layer than in the prior art. Can be.

Therefore, when the organic light emitting diode is manufactured using a novel compound having a high glass transition temperature as compared with the conventional art, it is possible to prevent deformation of the host material due to heat at a high temperature or a driving temperature, and thus the lifetime of the organic light emitting diode. Can improve.

In addition, when the organic light emitting device is manufactured using a novel compound having a higher triplet energy level and a lower singlet energy level and a triplet energy level difference, the organic light emitting device has a high luminous efficiency and It can improve the service life.

110: substrate
120: anode
130: hole injection layer
140: hole transport layer
150: light emitting layer
160: hole blocking layer
170: electron transport layer
180: electron injection layer
190: cathode

Claims (13)

A compound represented by the following formula (1).
[Formula 1]

Here, at least one of the X, Y and Z is made of nitrogen,
R 1 is selected from a substituted or unsubstituted aromatic compound, a heteroaromatic compound, and a silicon compound,
R 2 and R 3 are each independently selected from a substituted or unsubstituted aromatic compound and a heteroaromatic compound, hydrogen, deuterium, a silicon compound, and phosphoryl.
The method of claim 1,
X is nitrogen, and Y and Z are alpha-carboline groups each consisting of carbon, Y is nitrogen, and X and Z are beta-carboline groups each consisting of carbon, and Z is nitrogen, and X and Y may each be selected from a gamma carboline group consisting of carbon,
Substituted carboline groups are all the same or different compounds.
The method of claim 1,
The R1 is phenyl, dibenzothiphene, dibenzofuran, diphenylfuran, tetraphenylsilane, pyridine, quinolin, isoquinoline, pyrimidine pyrimidine) and substituents thereof.
The method of claim 3, wherein
The substituent of R1 is selected from the group consisting of alpha carboline group, beta carboline group, gamma carboline group, fluorene (fluorene) and substituents thereof.
The method of claim 3, wherein
Substituent of R1 is a compound selected from the group consisting of the formula A1 to A9.

The method of claim 1,
R2 and R3 are each independently hydrogen, phenyl, triphenylsilane, tetraphenylsilane, pyridine, quinolin, isoquinoline, pyrimidine ) And substituents thereof.
The method of claim 1,
Formula 1 is a compound represented by any one of the following formulas B1 to B17.

In the organic light emitting device comprising a light emitting layer between the anode and the cathode,
The emission layer includes a dopant material and a host material,
The host material is an organic electroluminescent device comprising the compound of any one of claims 1 to 7.
The method of claim 8,
The dopant material is an organic light emitting display device selected from the compounds represented by the following formula (2) or (3).
(2)

(3)

The method of claim 8,
The organic light emitting device of claim 1, wherein the dopant material contains 0.1 to 50% by weight based on the total weight of the host material and the dopant material.
The method of claim 8,
The compound represented by Formula 1 is an organic electroluminescent device which is a blue phosphorescent host material or a green phosphorescent host material.
The method of claim 8,
An organic material including any one or both of a hole injection layer and a hole transport layer between the anode and the light emitting layer, and one or both of a hole blocking layer, an electron transport layer and an electron injection layer between the light emitting layer and the cathode; Electroluminescent element.
13. The method of claim 12,
At least one of the hole blocking layer and the electron transport layer is an organic electroluminescent device comprising the compound of any one of claims 1 to 7.

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