KR100781921B1 - Carbazole derivatives, and organic light emitting diode employing the same - Google Patents

Abstract

A carbazole derivative and an organic electroluminescent device using the carbazole derivative are provided to improve luminous efficiency, lifetime, brightness and color reproduction range. A carbazole derivative is represented by the formula 1, wherein R is a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C3-C60 heteroaryl group, a substituted or unsubstituted fluorene group, or a C1-C20 alkyl group; Z1 to Z4 are identical or different one another and are H, a halogen atom, an alkyl group, an alkoxy group, a cyano group, a nitro group, or an acyl group; X1 and X2 are identical or different each other and are H, a halogen atom, an alkyl group, an alkoxy group, a cyano group, a nitro group, an acyl group, a substituted or unsubstituted amino group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted hetero ring having at least one halogen, nitrogen, oxygen or sulfur atom as a ring member; and Y1 and Y2 are identical or different each other and are H, a halogen atom, an alkyl group, an alkoxy group, a cyano group, a nitro group, an acyl group, a substituted or unsubstituted amino group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted hetero ring having at least one halogen, nitrogen, oxygen or sulfur atom as a ring member.

Description

Carbazole Derivatives, and Organic Light Emitting Diode Employing the Same}

1 is a cross-sectional view showing an example of the structure of an organic light emitting display device according to the present invention.

2 is a view showing a specific synthesis process of the compound of formula 1 according to the present invention.

FIG. 3 is a view showing an H analysis result of the andhracene derivative shown in FIG. 2.

Figure 4 is a view showing the H analysis of one embodiment of the compound of formula 1 according to the present invention.

5 is a view showing a red light emission spectrum of the light emitting layer composed of an embodiment of the compound of formula 1 according to the present invention and phosphorescent dopant.

6 is a view showing a blue light emission spectrum of the light emitting layer according to another embodiment of the compound of formula 1 according to the present invention.

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

101: substrate 102: anode

103: hole injection layer 104: hole transport layer

105: light emitting layer 106: electron transport layer

107: electron injection layer 108: cathode

The present invention relates to an organic electroluminescent device, and more particularly, to a compound for an organic electroluminescent device and an organic electroluminescent device including the same, which can greatly improve the efficiency, lifespan, and color purity of the organic light emitting device.

While CRT displays, which have been the mainstream of displays, have recently become increasingly interested in flat panel displays due to the demand for light weight, low power consumption, portability, and flattening, the replacement of liquid crystal displays (LCDs) is rapidly being made. As next generation flat panel displays, organic light emitting diodes (OLEDs) are attracting attention.

OLED is a display that can realize characters or images of various colors by emitting organic materials by itself when voltage is applied to organic material (polymer or low molecule) thin film. Self-emitting type, ultra thin type (1/3 of LCD), fast Its response speed (1000 times of LCD), low power consumption (1/2 of LCD), high sharpness and flexibility make it a popular small mobile display for mobile phones and PDAs. In the future, it is expected to develop into notebook PCs, wall-mounted TVs, and the display of scroll TVs as simple and clear as paper after 2010.

OLED emits visible light by recombination of holes and electrons, and has a form in which a plurality of organic layers are stacked between a cathode and an anode as shown in FIG. 1. Generally, substrates for OLED devices are made of glass, but in some cases, bendable plastic or film types are used. The anode electrode on the substrate mainly uses indium-tin oxide (hereinafter referred to as "ITO") formed by vacuum deposition or sputtering, and the organic layer is vacuum-deposited for low molecular weight compounds and high-molecular compounds. Thin films are formed by spin coating or inkjet printing. The negative electrode requires magnesium or lithium having a small work function, but aluminum is mainly used in consideration of stability with atmospheric moisture and oxygen.

   OLED devices using low molecular weight compounds generally use an anode, a hole injection layer (HIL) for receiving holes from an anode, and a hole transporting layer (HOL) for transferring holes. ), A light emitting layer that combines holes and electrons to emit light (hereinafter referred to as EML), and an electron transporting layer that receives electrons from a cathode and transfers them to the light emitting layer (hereinafter referred to as 'ETL'). It consists of an Electron Injection Layer (hereinafter referred to as 'EIL') and a cathode that accepts electrons from the cathode.

In order to operate the OLED device at low voltage, it is very important to control the process so that the overall thickness of the organic thin film layer is about 100 to 200 nm and a uniform thin film is formed on each layer. As a large amount of charges (holes and electrons) are injected, when the amount of injected electrons and holes is balanced, exciton formation efficiency in the light emitting layer is increased, thereby improving luminous efficiency.

   In other words, HIL and EIL increase the amount of holes and electrons injected from the anode and cathode, respectively, and HTL and ETL receive holes and electrons from HIL and EIL and transfer them to the light emitting layer quickly. It will serve to trap the former. That is, a large amount of holes and electrons are collected in the light emitting layer by HIL, HTL, ETL, and EIL to induce a large amount of excitons in the light emitting layer. As a result, the luminous efficiency is increased.

   As another method of increasing the luminous efficiency, a dramatic increase in luminous efficiency may be induced by mixing the EML layer with two materials, namely, a host and a dopant. In other words, when 90 to 99% of the host and 1 to 10% of the dopant are deposited, energy transfer to the dopant is concentrated, and thus, the probability of formation of excitons in the dopant is rapidly increased, thereby increasing the luminous efficiency.

   Currently, OLED is being applied to small applications, and like other displays, R & D is focused on large-area OLED implementation as part of the expansion of its application field and formation of large-scale OLED market. The most important field of application of large area OLED is TV field. Large area OLED implementations for such TV applications include backplane technology, RGB patterning technology (shadow masking technology, Inkje technology, LITI technology, etc.), large area Encap. In addition to the development of process technologies such as technology, performance enhancements such as brightness, power consumption, color reproduction range, and lifespan should be achieved.

   As described above, the materials for HIL, HTL, EML (host & dopant), HBL (hole blocking layer), ETL, and EIL, which are involved in the emission of OLEDs, have no major problems in performance for cellular phones. However, brightness, power consumption, color gamut and lifespan for TV applications need improvement. As such, in order to implement a large area OLED in a TV, it is essential to improve the performance of each material, and a material suitable for the application has not been developed.

Phosphorescent materials are theoretically four times more efficient than fluorescent materials among OLED's light emitting materials, and recently, green and red phosphorescent materials have reached the level of commercialization. The use of phosphors in OLED devices requires the formation of a hole blocking layer (HBL) between the EML and the ETL. In addition, since the light is emitted in a triplet state, the OLED is applied to a fluorescent OLED device. There is a problem that the host material is not applicable to phosphorescent devices. In other words, it is required to develop a new material capable of energy transfer from the triplet state to the phosphorescent dopant.

Conventional source technologies in the technical field related to the conventional OLED materials and phosphorescent materials mentioned above are EP 1 571 193 A1, EP 1 551 206, Korean Patent No. 10-2005-0099270 (Publication Number), Korean Patent 10- 2003-0041968 (publication number), Korea Patent 10-0392972 (registration number), Korea Patent 10-0387166 (registration number), Japanese Patent Laid-Open No. 7-252474 and the like. The introduction and problems of the conventional OLED materials are as follows.

In the OLED device, the electron transport layer contains an electron transport compound, a compound having an electron pulling body capable of stabilizing anion radicals generated when electrons are injected from the cathode, or a metal compound capable of well receiving electrons. Mainly used. Compounds having an electron-gripping body include compounds containing functional groups (-C = N-) that resonate electrons by resonance, such as cyan groups, oxadiazoles, and triazoles. 8-hydroxyquinoline aluminum salt (Alq3) and PBD (2-biphenyl-4-yl-5- (4-t-butylphenyl) -1,3,4-oxadiazole), which typically serve as electron transport and hole binding , spiro-PBD, but Alq3 is the most commonly used. Alq3 has been in use since the late 1980s when OLEDs gained commercial value and is still in use today. However, Alq3 is vulnerable to moisture and oxygen, which is problematic in terms of ensuring at least 20,000 hours of life for TV applications and needs improvement.

The hole injection layer and the hole transport layer contain a hole transport compound, which facilitates hole injection from the anode, and ultimately improves the power efficiency of the device and increases the life of the device. In order to lower the hole injection barrier, the ionization energy should be similar to the work function of the anode ITO, and the interfacial adhesion with the ITO should be high. The hole transport layer not only transports the injected holes to the light emitting layer easily but also binds the electrons to the light emitting area to increase the probability of exciton formation and must be a material having high hole mobility. However, the materials used in such conventional OLED devices do not exhibit sufficient performance required for practical use, particularly in TV applications. One of the main reasons for this is the low heat resistance of the hole injection / transport material. Joule heat generated during OLED operation causes crystallization of the hole transport material to form dark spots. Therefore, the hole injection material or the hole transport material is preferably in an amorphous state while excellent in heat resistance. Conventionally used hole injection / transport materials are mainly used aromatic amines that can stabilize the radicals generated during hole injection, biphenyl diamine derivatives, starburst type compounds, spiro groups Biphenyl diamine derivatives, ladder compounds, and the like are known, but only a few are known to be suitable for practical use. NPD (N, N'-bis (1-naphthyl) -N, N'-diphenyl-1,1'-biphenyl-4,4'-diamine) is the most widely used hole transport layer material. It shows the transition temperature (Tg) and is currently used in 2 inch OLED products. Therefore, if the material is used in OLEDs applied to the TV field, crystallization occurs due to heat generation, resulting in a decrease in TV brightness and lifespan.

In terms of light emitting materials, many green and red materials have been developed with some characteristics, but have not yet reached the level of TV application. In particular, blue materials with a large band gap are recognized as more difficult technologies than other materials. As an example, there are very few published examples of low molecular weight phosphor blue, and polymer blue has also been pointed out to have a short lifespan that is difficult to apply to commercial products. In addition, commercially available low molecular weight blue fluorescent materials have few materials close to NTSC color coordinates (blue; 0.14, 0.08), and some material companies and research institutes announce high-purity blue, It is known to have low commercial applications.

As mentioned above, in the case of phosphorescent devices, the development of a new host material is required. In the past, the application of fluorene-based materials has been considered, but the energy level of the triplet is suitable for interacting with the energy level of the dopant. There is a problem that is not.

In relation to the above, the conventional materials and the materials currently used industrially have been reviewed based on various studies and experiments, but they are suitable for small OLEDs, but in terms of efficiency, color coordinates, and lifetimes for OLEDs for medium-large sized TV applications. There was a problem that the characteristics are significantly short.

The technical problem to be achieved by the present invention is to provide a compound in which at least two andrasene derivatives are substituted in the carbazole (carbazole) as the formula (1).

Another object of the present invention is to provide an organic electroluminescent device comprising a compound in which at least two andrasene derivatives are substituted in carbazole, which is a central group, as shown in the general formula (1).

The organic compound according to the present invention for achieving the above technical problem is represented by the following formula (1).

<Formula 1>

Here, R is a C6-C60 aryl group which may have a substituent, a C3-C60 heteroaryl group which may have a substituent, or a fluorene group or a C1-C20 alkyl group which may have a substituent. Z ₁ to Z ₄ may be the same or different and may be selected from hydrogen, halogen, alkyl, alkoxy, cyano, nitro and acyl. And X ₁ , X ₂ may be the same or different, hydrogen atom, halogen atom, alkyl group, alkoxy group, cyano group, nitro group, acyl group, substituted or unsubstituted amino group, substituted or unsubstituted aryl group, substituted or unsubstituted It may be selected from cyclic heterocyclic groups. And Y ₁ , Y ₂ may be the same or different, hydrogen atom, halogen atom, alkyl group, alkoxy group, cyano group, nitro group, acyl group, substituted or unsubstituted amino group, substituted or unsubstituted aryl group, substituted or unsubstituted It may be selected from cyclic heterocyclic groups.

According to another aspect of the present invention, there is provided an organic light emitting display device including: a first electrode, at least one organic compound layer including a light emitting layer, and a second electrode; At least one organic compound layer of the compound layer is characterized in that it contains at least one compound of the formula (1).

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings and the chemical formula.

In order to describe the formula (1) according to the present invention in more detail, the type of the compound that is bonded to carbazole, namely andhrasene derivatives are represented in the formula (2), formula (3), in addition to the structure shown here may be a myriad of examples.

<Formula 2>

Z ₅ and Z ₆ are selected from a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a cyano group, a nitro group, an acyl group, a substituted or unsubstituted amino group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group.

<Formula 3>

Z ₇ and Z ₈ are selected from a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a cyano group, a nitro group, an acyl group, a substituted or unsubstituted amino group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group.

Formula 1 according to the present invention is based on carbazole, and is a new structure that is not known until the at least two substituents, such as the above-described formulas (2) and (3) are substituted, the core is formed of an andracene derivative Characteristic. Carbazole itself is capable of blue light emission, and has been reported to be suitable as a host material of high efficiency phosphorescent materials, which has recently emerged, but it has been difficult to be applied to OLED devices because of low electron affinity. Formula 1 according to the present invention is characterized by the chemical introduction of andrasene, which is excellent in electron withdrawing characteristics and thermally stable, and itself is capable of blue light emission in order to solve the problem of low electron affinity of carbazole. As a result, it is possible to secure a blue light emitting material having excellent electron affinity, and in particular, there is an advantage that the application of the phosphorescent dopant as a host material is also possible. In the case of the materials introduced in the prior art, the combination with Carbazole is a tertiary amine form combined with two different aryl groups including nitrogen atoms, which can be said to be novel because it is distinguished from the structural aspects of the present invention.

As described above, at least two or more substituents may be the same as or different from each other. In addition, the position of the substituent may be selected from two carbons 1, 2, 3, 4, 5, 6, 7, 8 of the Carbazole group. In other words, when two andhrasene derivatives are introduced, the arable structure is 13 (1,5 / 1,6 / 1,7 / 1,8 / 2,5 / 2,6 / 2,7 / 2,8 / 3). , 6 / 3,7 / 3,8 / 4,7 / 4,8). Some examples are given below as in Chemical Formulas 4 and 5.

<Formula 4>

Here, R is a C6-C60 aryl group which may have a substituent, a C3-C60 heteroaryl group which may have a substituent, or a fluorene group or a C1-C20 alkyl group which may have a substituent. Z ₁ to Z ₄ may be the same or different and may be selected from hydrogen, halogen, alkyl, alkoxy, cyano, nitro and acyl. And X ₁ , X ₂ may be the same or different, hydrogen atom, halogen atom, alkyl group, alkoxy group, cyano group, nitro group, acyl group, substituted or unsubstituted amino group, substituted or unsubstituted aryl group, substituted or unsubstituted It may be selected from cyclic heterocyclic groups. And Y ₁ , Y ₂ may be the same or different, hydrogen atom, halogen atom, alkyl group, alkoxy group, cyano group, nitro group, acyl group, substituted or unsubstituted amino group, substituted or unsubstituted aryl group, substituted or unsubstituted It may be selected from cyclic heterocyclic groups.

<Formula 5>

Here, R is a C6-C60 aryl group which may have a substituent, a C3-C60 heteroaryl group which may have a substituent, or a fluorene group or a C1-C20 alkyl group which may have a substituent. Z ₁ to Z ₄ may be the same or different and may be selected from hydrogen, halogen, alkyl, alkoxy, cyano, nitro and acyl. And X ₁ , X ₂ may be the same or different, hydrogen atom, halogen atom, alkyl group, alkoxy group, cyano group, nitro group, acyl group, substituted or unsubstituted amino group, substituted or unsubstituted aryl group, substituted or unsubstituted It may be selected from cyclic heterocyclic groups. And Y ₁ , Y ₂ may be the same or different, hydrogen atom, halogen atom, alkyl group, alkoxy group, cyano group, nitro group, acyl group, substituted or unsubstituted amino group, substituted or unsubstituted aryl group, substituted or unsubstituted It may be selected from cyclic heterocyclic groups.

Examples of the formula (1) according to the present invention can be a myriad, brief description of the preparation method when R is an ethyl group in a variety of materials, and dihalo-9-ethylcarbazole in the presence of a catalyst It can be prepared by the reaction of.

  At this time, as dihalo-9-ethylcarbazole, dibromo-9-ethylcarbazole, diiodo-9-ethylcarbazole, dichloro-9-ethylcarbazole, etc. may be mentioned.

  Andhrasene derivatives that react with dihalo-9-ethylcarbazole can be used if the compound is halogen-bonded to carbon number 9 in the structures shown in Formulas 2 and 3, and can be easily synthesized through the suzuki-coupling reaction.

  The object of the present invention is to provide an electroluminescent device comprising the compound of the formula (1) as described above, as another object of the present invention. More specifically, in an organic light emitting display device in which a first electrode, an organic material layer including one or more layers including a light emitting layer, and a second electrode are sequentially stacked, one or more layers of the organic material layers include a compound of Formula 1 An object of the present invention is to provide an organic light emitting display device.

1 is a cross-sectional view showing an example of the structure of an organic light emitting display device according to the present invention.

Referring to the specific implementation method of the organic light emitting device comprising the compound of formula 1 shown in Figure 1 as follows. A transparent electrode pattern of the anode 102 was formed on the substrate 101 as the first electrode, followed by a hole injection layer 103, a hole transport layer 104, a light emitting layer 105 of Formula 1, an electron transport layer 106, By sequentially forming the electron injection layer 107 and forming a cathode 108 as a second electrode, an organic light emitting display device may be realized. The light emitting layer 105 may include a second component in addition to the formula (1). In addition, when the second component is a phosphorescent dopant, a hole blocking layer (HBL) may be added between the light emitting layer 105 and the electron transport layer 106.

In this case, indium tin oxide (ITO) having electrical conductivity and transparency at the same time is mainly used. In addition, the substrate 101 may be provided with a thin film transistor (TFT), and when the TFT is provided, an active matrix type electroluminescent device may be manufactured. When the TFT is not provided, the substrate 101 may be passively driven. (passive matrix type) electroluminescent device can be manufactured. In the present invention, either an active drive type or a passive drive type may be used. In addition, the substrate may be used, such as glass, plastic, metal foil, and is not particularly limited.

The hole injection layer 103 is not particularly limited. The hole injection layer 103 may be a material that plays a role of smoothing the surface of the transparent electrode and is excellent in interfacial characteristics with the transparent electrode and easily gives electrons to the transparent electrode. Representative hole injection material is the same as the conventional formula 6 (DNTPD), it is preferable to form about 300 ~ 1200 mm 3.

<Formula 6>

The hole transport layer 104 is a material that has a high physical and chemical similarity to the hole injection layer 103, and, like the hole injection layer 103, a material that can easily give electrons, that is, a material that can easily transport holes, is particularly preferable. It is not restricted. Representative hole transport material according to the prior art is the same as the general formula (7) (NPD), it is preferable to form a thickness of about 300 ~ 500 mm by heat deposition under vacuum.

<Formula 7>

Next, formation of the light emitting layer 105 is required. In the case of a full color display, a red light emitting layer, a green light emitting layer and a blue light emitting layer should be formed in the pixel. In this case, as an example, a compound in which two substituents are both Formula 2 (Z ₅ and Z ₆ are small atoms) and R is an ethyl group may be used to form a blue light emitting layer. That is, it is preferable that the substrate on which the electron injection layer is formed is disposed in a vacuum chamber of 10 ⁻⁶ torr, and the compound of the present invention is heated to be deposited at a rate of 5 kW / sec to form a light emitting layer having a thickness of 300 kW. In this case, the light emitting layer may include a dopant, and conventionally known green dopants include 10- (2-benzothiazolyl) -1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H, 5H, 11H. -[1] benzopyrano [6,7,8-ij] quinolizin-11-one and its derivatives and quinacridone derivatives are possible. Red dopants include Kodak's DCJTB and its derivatives and Sony's 1,1'-dicyano-substituted bisstryl naphthalene may be used, and as blue dopant, diphenylamino-di (styryl) arylene may be used. As the phosphorescent dopant, Ir or Pt-based organometallic complexes can be used, and green, blue and red light can be emitted depending on the type of the ligand constituting the Ir or Pt complex. Examples include red phosphorescent material 2,3,7,8,12,13,17,18-octaethyl-12H, 23H- porphyrineplatinum (II) (PtOEP) and green phosphorescent material fac-tris (2-phenylpyridine) iridium ( Ir (ppy) ₃ ], bis (2- (2'-benzo [4,5-a] thienyl) pyridinato-N, C ^{2 '} ) iridium (acetylacetonate) (Btp ₂ Ir (acac)) Blue phosphor, fac-tris [2- (4,5'-difluorophenyl) pyridine-N, C ' ³ ] iridium (III) (FIrppy), etc. If a phosphorescent dopant is used as a dopant, If a hole blocking layer (HBL) is formed by depositing a material such as 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), better efficiency can be obtained.

The electron transport layer 106 needs to be formed on the light emitting layer 105 or on the hole blocking layer, and various known materials may be used. That is, it is preferable to include an electron accepting group so that electrons can be easily transferred to the light emitting layer 105, and the following Chemical Formula 8 (Alq3) is representative. Since the formation position of the exciton is affected by the thickness of the electron transport layer 106, the film thickness must be appropriately adjusted. In other words, if the electron transport layer 106 is too thick, the light emitting region is biased by the electron transport layer 106, and thus some light emission occurs in the electron transport layer 106, so that the color coordinates are deteriorated. On the other hand, if formed too thin, there is a disadvantage that the life is reduced, so about 200 ~ 400 Å is suitable.

<Formula 8>

The electron injection layer 107 is formed on the electron transport layer 106, and many LiFs are industrially used. A cathode 108, which is a second electrode, is formed on the electron injection layer 107. Al, Ma, Ag, or a single metal may be used as the cathode, and dozens of nm of Ca, Ba, etc. may be formed between LiF, the electron injection layer 107, and Al, the cathode 108, to form LiF / Ca (or A negative electrode having a Ba / Al structure may also be used. After cathode formation, the electroluminescent device is completed through encapsulation process to block the atmosphere.

As described above, the structural features and manufacturing method of Chemical Formula 1 according to the present invention and a method of implementing the electroluminescent device using the same are described, but the present invention is not limited to the above-described range. That is, according to the type of substituent in Formula 1, green and red light emitting materials, a host material of the light emitting layer, a hole transport material and an electron transport material may be implemented.

Hereinafter, a method for preparing a novel compound and a method for implementing an organic light emitting display device according to the present invention will be embodied through examples, but the present invention is not limited to the following examples, which are only presented to aid the understanding of the present invention.

Example 1

As a specific example of Formula 1, 3,6-di (anthracen-10-yl) -9-ethylcarbazole (Compound 2 ) was synthesized, and a detailed synthesis process is shown in FIG. 2.

First, to synthesize andrasene derivatives, commercially available 9-bromoanthrancene (15.6 mmol) was purified in 25 mL of toluene and stirred under nitrogen, followed by Pd (PPh ₃ ) ₄ (960 mg, 0.05 eq) and Et _3. Add N (6.4 mL, 2.9 eq) and pinacolborane (3.5 mL, 1.5 eq) and stir at reflux for 16 hours. After confirming the completion of the reaction by TLC, the solvent was removed under reduced pressure, the compound was extracted using EtOAc and water, and the solvent was removed under reduced pressure and purified by separation to give the compound 1 (3.5 g, 74%) andrasene derivative. ¹ H analysis results of the synthesized compound 1 are shown in FIG. 3.

1 : Elemental analysis calculated for C ₂₀ H ₂₁ BO ₂ : C, 78.97; H, 6.96; 0, 10.52; found C, 78.99; H, 6.94; O, 10.72.

To make compound 2 , commercially available 3,6-dibromo-9-ethylcarbazole (1.0 g, 2.83 mmol) and Pd (PPh ₃ ) ₄ (0.05eq) were added to purified 20 mL of toluene at room temperature under nitrogen. Stir for a minute. To the reaction was added 5 mL of 1M Na 2 CO 3 solution, Compound 1 (2.2eq), and the mixture was stirred under reflux for 24 hours. After confirming the completion of the reaction by TLC, the solvent was removed under reduced pressure, the product was extracted using water and EtOAc, water was removed with anhydrous magnesium sulfate, and then the solvent was removed under reduced pressure. The product was separated and purified using a silica gel column to obtain pure 3,6-di (anthracen-10-yl) -9-ethylcarbazole (Compound 2 , 66 % ). Synthesized Compound 2 was dried with a vacuum dryer, and a high purity material of about 99.7% was obtained by using a sublimation purification apparatus equipped with a turbopump. ¹ H analysis results of the synthesized compound 2 are shown in FIG. 4.

2 : Elemental analysis calculated for C ₄₂ H ₂₉ N: C, 92.11; H, 5. 34; N, 2.56; found C, 92.05; H, 5. 34; N, 2.41.

ITO glass with a sheet resistance of 30 Ω per unit area, a thickness of 1.08 mm and a light transmittance of 80% or more was cut to a size of 2 cm 2 cm, followed by nitric acid (70%), hydrochloric acid and distilled water. The ITO layer was partially removed using an etchant mixed at a ratio of: 210: 80. In addition, the etched ITO glass was placed in a beaker containing acetone and washed with an ultrasonic cleaner for 15 minutes, and then placed in CA-40 (Cyantek Co.), an ITO glass cleaning solution, for 15 minutes. Finally washed several times with deionized water and dried for 1 hour at 120 ℃.

DNTPD was formed on the substrate on which the transparent electrode pattern formation and cleaning was completed as a hole injection material to a thickness of 700 Å by vacuum heating evaporation method, and NPD was formed to a thickness of 300 Å as the hole transport material. Subsequently, Compound 2 and a red phosphorescent dopant synthesized and purified by the method described above as a light emitting layer (bsn) ₂ Ir (acac) [a phosphorescent red dopant in which two naththalene benzothiozoles and one acethylacetonate ligand formed a complex with Ir were 95 The film was formed at a ratio of 5: 5 to form a thickness of 350 GPa, and then Alq3, which was an electron transport layer, was formed at a thickness of 200 GPa. As the electron injection layer, LiF was formed to a thickness of 10 kV on the electron transport layer, and Al was formed to have a thickness of 1500 kPa on the upper portion. The fabricated electroluminescent device was cut off from the atmosphere using a glass cap.

When a direct current was applied by connecting an anode to ITO and a cathode to Al, a red light emission of color coordinates x = 0.61 and y = 0.38 was obtained from the light emitting layer composed of Compound 2 and phosphorescent dopant. At this time, no emission of light by Compound 2 was observed, and from this, it could be seen that energy transfer from Compound 2 to phosphorescent dopant occurred easily. The red light emission spectrum is shown in FIG. 5.

Example 2

As another specific example of Chemical Formula 1, 2,7-di (anthracen-10-yl) -9-ethylcarbazole (Compound 3 ) was synthesized, and the synthesis process is shown in FIG. 2.

Similar to the method shown in Example 1, 2,7-dibromo-9-dthylcarbazole and 9-bromoanthrancene were used to synthesize compound 3 having anthrancene group introduced at the 2,7 position of carbazole. Compound 3 (60%) was subjected to chemical purification and sublimation purification in a similar manner to Example 1 to obtain a high purity material of 99.6%.

3: Elemental analysis calculated for C ₄₂ H ₂₉ N: C, 92.11; H, 5. 34; N, 2.56; found C, 92.15; H, 5.39; N, 2.44.

6 is a view showing a blue light emission spectrum of the light emitting layer according to another embodiment of the compound of formula 1 according to the present invention.

ITO pattern formation and cleaning were completed by the method described in Example 1, and DNTPD was formed on the substrate as a hole injection material to a thickness of 500 mm by vacuum heating deposition method, NPD as a hole transport material 250 mm thick Formed. Subsequently, Compound 2, which was synthesized and purified by the method described above as a light emitting layer, was formed to a thickness of 300 GPa, and then Alq3, which is an electron transport layer, was formed to a thickness of 250 GPa. LiF was formed to a thickness of 10 kV on the electron transport layer, and Al was formed to a thickness of 2000 mW. The fabricated electroluminescent device was cut off from the atmosphere using a glass cap.

When the direct current was applied by connecting a positive electrode to ITO and a negative electrode to Al, blue light emission from the compound 3 was obtained as shown in FIG. 6.

The technical spirit of the present invention has been described above with reference to the accompanying drawings. However, the present invention has been described by way of example only, and is not intended to limit the present invention. In addition, it is apparent that any person having ordinary knowledge in the technical field to which the present invention belongs may make various modifications and imitations without departing from the scope of the technical idea of the present invention.

The compound according to the present invention and the organic light emitting device including the same improve the luminous efficiency and lifespan, and can implement a full color display excellent in high brightness and color reproduction range, which can be applied to an OLED TV.

Claims (11)

Compound represented by the following formula (1): <Formula 1>

Here, R is a C6-C60 aryl group which may have a substituent, a C3-C60 heteroaryl group which may have a substituent, or a fluorene group or a C1-C20 alkyl group which may have a substituent, Z ₁ to Z ₄ may be the same or different and may be selected from a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a cyano group, a nitro group and an acyl group, X ₁ , X ₂ may be the same or different, hydrogen atom, halogen atom, alkyl group, alkoxy group, cyano group, nitro group, acyl group, substituted or unsubstituted amino group, substituted or unsubstituted aryl group, substituted or unsubstituted Can be selected from heterocyclic groups, Y ₁ , Y ₂ may be the same or different, hydrogen atom, halogen atom, alkyl group, alkoxy group, cyano group, nitro group, acyl group, substituted or unsubstituted amino group, substituted or unsubstituted aryl group, substituted or unsubstituted It may be selected from heterocyclic groups. The compound of claim 1, wherein the compound is represented by one of the following Chemical Formulas 4 to 5: <Formula 4>

<Formula 5>

Here, R is a C6-C60 aryl group which may have a substituent, a C3-C60 heteroaryl group which may have a substituent, a fluorene group which may have a substituent, or a C1-C20 alkyl group, Z ₁ to Z ₄ may be the same or different and may be selected from a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a cyano group, a nitro group and an acyl group, X ₁ , X ₂ may be the same or different, hydrogen atom, halogen atom, alkyl group, alkoxy group, cyano group, nitro group, acyl group, substituted or unsubstituted amino group, substituted or unsubstituted aryl group, substituted or unsubstituted Can be selected from heterocyclic groups, Y ₁ , Y ₂ may be the same or different, hydrogen atom, halogen atom, alkyl group, alkoxy group, cyano group, nitro group, acyl group, substituted or unsubstituted amino group, substituted or unsubstituted aryl group, substituted or unsubstituted It may be selected from heterocyclic groups. In an organic light emitting display device comprising a first electrode, at least one organic compound layer including a light emitting layer, and a second electrode sequentially stacked, at least one organic compound layer of the organic compound layer is the compound of claim 1 or claim 2 At least one organic light emitting device, characterized in that it is included The method of claim 3, The light emitting layer is an organic light emitting display device, characterized in that the binary compound of the host and the dopant  The method of claim 4, wherein The material constituting the host is an organic light emitting display device, characterized in that the compound of claim 1 or 2. The method of claim 4, wherein The material constituting the dopant is an organic light emitting device, characterized in that the compound of claim 1 or 2. The method of claim 3, The organic compound layer includes a hole transport layer, The organic light emitting device, characterized in that the hole transport layer comprises at least one compound of claim 1 or claim 2. The method of claim 3, The organic compound layer includes a hole blocking layer, The organic light emitting device, characterized in that at least one compound of claim 1 or 2 in the hole blocking layer. The method of claim 3, The organic compound layer includes an electron transport layer, The organic light emitting device, characterized in that at least one compound of claim 1 or 2 in the electron transport layer. The method of claim 3, The organic compound layer includes a hole injection layer, The organic light emitting device, characterized in that at least one compound of claim 1 or 2 in the hole injection layer. The method of claim 3, The organic compound layer includes a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer and an electron injection layer, Organic electroluminescence, characterized in that at least one compound of claim 1 or 2 is included in at least one layer selected from the hole injection layer, the hole transport layer, the light emitting layer, the electron transport layer and the electron injection layer. device

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