KR20100007552A - Asymmetric anthracene derivatives and electroluminescent devices comprising same - Google Patents

Abstract

PURPOSE: An asymmetric anthracene derivative is provided to ensure high color purity and excellent luminous efficiency and luminescent brightness and to realize long lifetime compared with a conventional material, and to improve driving voltage, luminous efficiency, color purity and lifetime property. CONSTITUTION: An asymmetric anthracene derivative has a structure represented by chemical formula 1. In chemical formula 1, R^1 - R^3 are independently hydrogen, halogen, C1-30 alkyl group containing or not containing at least one hetero atom among S, N, O, P and Si, C2-40 alkenyl group, C5-60 cycloalkyl group or C5-60 arylalkyl group; and Ar^1-Ar^2 are independently C5-50 aryl group or polycyclic aromatic group, or C5-60 aryl group containing C1-30 alkyl group containing or not containing at least one hetero atom among S, N, O, P and Si, or polycyclic aromatic group.

Description

Asymmetric anthracene derivatives and organic electroluminescent device comprising the same {ASYMMETRIC ANTHRACENE DERIVATIVES AND ELECTROLUMINESCENT DEVICES COMPRISING SAME}

The present invention relates to a novel asymmetric anthracene derivative usable as a blue light emitting layer material and an organic light emitting device comprising the same.

Recently, an organic light emitting device capable of low-voltage driving with a self-luminous type has superior viewing angles, contrast ratios, and the like, and is lighter and thinner than a liquid crystal display (LCD), which is a mainstream of flat panel display devices. In addition, it is advantageous in terms of power consumption and wide color reproduction range, attracting attention as a next-generation display device.

In general, an organic light emitting display device has a structure including a cathode (electron injection electrode), an anode (hole injection electrode), and an organic layer between the two electrodes. In this case, the organic layer may include a hole injection layer (HIL), a hole transport layer (HTL), an electron transport layer (ETL), or an electron injection layer (EIL) in addition to the light emitting layer (EML). , an electron injection layer, and may further include an electron blocking layer (EBL) or a hole blocking layer (HBL) due to light emission characteristics of the light emitting layer. 1 illustrates a structure of a general organic light emitting display device having a structure in which an anode / hole injection layer / hole transport layer / light emitting layer / hole blocking layer / electron transport layer / electron injection layer / cathode is stacked in this order.

When an electric field is applied to the organic light emitting device having such a structure, holes are injected from the anode, electrons are injected from the cathode, and holes and electrons are recombined in the light emitting layer through the hole transport layer and the electron transport layer, respectively, thereby emitting light. form exitons). The formed light exciton emits light as it transitions to ground states. In order to increase the efficiency and stability of the light emitting state, a light emitting dye (dopant) may be doped into the light emitting layer (host).

Various compounds including an anthracene structure are known as a light emitting material used in the light emitting layer of the organic light emitting device.

[Document 1] US 2007/0152565 (Idemitsu Kosan) December 13, 2004

[Document 2] US 2007/0055085 (Idemitsu Kosan) 2004. 11. 30.

[Document 3] JP 4,041,816 (Idemitsu Kosan) 2003. 8. 18.

Document 4 US 20050233165 (Idemitsu Kosan) 2003. 7. 29.

[Document 5] JP 4,025,136 (Idemitsu Kosan) July 31, 2002.

[Document 6] US 7,053,255 (Idemitsu Kosan) 2001. 11. 2.

[Document 7] US 6,534,199 (Idemitsu Kosan) September 20, 2000.

[Document 8] US 6,465,115 (Kodak) December 9, 1998

Document 9 US 5,935,721 (Kodak) March 20, 1998.

However, in the case of the organic light emitting device using the light emitting material including an anthracene structure known so far, there are many difficulties in practical use due to the high driving voltage, low luminous efficiency and short lifespan. Therefore, efforts have been made to develop organic light emitting diodes having low voltage driving, high efficiency, and long life using various kinds of light emitting materials including anthracene structures.

Accordingly, an object of the present invention is to provide a blue light emitting material having excellent light emitting ability, which can significantly improve driving voltage, light emitting efficiency, and lifetime characteristics of an organic light emitting display device, and an organic light emitting display device including the same.

In order to achieve the above object, the present invention provides a compound represented by the following Chemical Formula 1:

In Chemical Formula 1,

R ¹ To Each R ³ is independently a C _1-30 alkyl group, C _2-40 alkenyl group, C _5-60 cycloalkyl group, containing or without at least one hetero atom of hydrogen, halogen, S, N, O, P and Si; C _5-60 arylalkyl group, wherein R ¹ To R ³ may be substituted or unsubstituted with F or Cl,

Ar ¹ to Ar ² are each independently a C _5-50 aryl group, or a polycyclic aromatic group; A C _5-60 aryl group or a polycyclic aromatic group including a C _1-30 alkyl group containing or not containing at least one hetero atom of S, N, O, P and Si.

In addition, the present invention provides an organic light emitting device comprising the compound of Formula 1 in the light emitting layer as a light emitting material.

Since the compound of the present invention has excellent luminous ability compared to the conventional material, it can be used as a light emitting material of the organic light emitting device can significantly improve the driving voltage, luminous efficiency and life characteristics of the organic light emitting device.

In the compound of Formula 1 according to the invention, preferably R ¹ To Each R ³ is independently hydrogen, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, neo-pentyl, hexyl, heptyl, octyl, methoxy, ethoxy, cyclopentyl , Cyclohexyl, cycloheptyl, monophenylmethyl, diphenylmethyl, triphenylmethyl, trimethylsilyl, trichloromethyl, trifluoromethyl, triphenylmethyl, tetrahydropyranyl, 2-phenylisopropyl, Cl or F ego;

Ar ¹ to Ar ² are each independently phenyl, 1-naphthyl, 2-naphthyl, 4-methylnaphthyl, 5-methylnaphthyl, biphenyl, 4-methylbiphenyl, 4-ethylbiphenyl, 4- Cyclohexylbiphenyl, terphenyl, 3,5-dichlorophenyl, anthryl, pyrenyl, benzofuranyl, benzothiophenyl, benzothiazolyl, quinoline, isoquinoline, fluorenyl, dimethylfluorenyl, di Phenylvinylphenyl, spirobifluorenyl, diphenylanthracenyl, dinaphthalenylanthracenyl, difluorenylanthracenyl, naphthylanthracenyl or phenanthryl.

Specific examples of the compound represented by Formula 1 are compounds represented by the following compounds 1 to 80:

The compound of Formula 1 according to the present invention may be prepared by the aromatic boron compound and the aromatic halogen compound through the Suzuki-coupling reaction, which is widely known among carbon-carbon coupling reactions. For example, a compound of Formula 1 of the present invention can be prepared as shown in Scheme 1:

Where

R ¹ to R ³ , Ar ¹ and Ar ² are as defined above,

When A is B (OH) ₂ , D is a halogen atom,

When D is B (OH) ₂ , A is a halogen atom.

In addition, the present invention provides an organic light emitting device comprising the compound of Formula 1 in the light emitting layer as a light emitting material. In this case, the compound of Formula 1 may be used as a single light emitting material or a light emitting host (host) of the light emitting layer.

The organic electroluminescent device of the present invention has a structure in which an anode (hole injection electrode), a light emitting layer containing the compound of Formula 1 and a cathode (electron injection electrode) are sequentially stacked, preferably, electrons between the anode and the light emitting layer The blocking layer EBL may further include an electron transport layer ETL, an electron injection layer EIL, or a hole blocking layer HBL between the cathode and the light emitting layer.

1 illustrates a structure of an organic light emitting diode stacked on a substrate in the order of anode / hole injection layer / hole transport layer / light emitting layer / hole blocking layer / electron transport layer / electron injection layer / cathode.

First, a positive electrode is coated on a surface of a substrate by a conventional method to form a positive electrode. At this time, the substrate used is preferably a glass substrate or a transparent plastic substrate excellent in transparency, surface smoothness, ease of handling and waterproofness. In addition, as the positive electrode material, indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO ₂ ), zinc oxide (ZnO), and the like, which are transparent and have excellent conductivity, may be used.

Next, a hole injection layer is formed on the surface of the anode by vacuum thermal evaporation or spin coating of a hole injection layer (HIL) material in a conventional manner. At this time, the hole injection layer material is not particularly limited, and for example, copper phthalocyanine (CuPc), 4,4 ', 4 "-tris (3-methylphenylamino) triphenylamine (m-MTDATA), 4,4' 4,4'-tris (3-methylphenylamino) phenoxybenzene (m-MTDAPB), starburst amines 4,4 ', 4 "-tri (N-carbazolyl) triphenylamine (TCTA), 4,4 ', 4 "-tris (N- (2-naphthyl) -N-phenylamino) -triphenylamine (2T-NATA) or N, N'-di-1 available from Idemitsu -Naphthyl-N, N'-bis ((4-diphenylamino) phenyl) benzidine (IDE406) can be used.

A hole transport layer is formed on the surface of the hole injection layer by vacuum thermal evaporation or spin coating of a hole transport layer (HTL) material in a conventional manner. At this time, the hole transport layer material is not particularly limited, for example, bis (N- (1-naphthyl-n-phenyl)) benzidine (α-NPD), N, N'-di (naphthalen-1-yl ) -N, N'-diphenyl-benzidine (NPB) or N, N'-diphenyl-N, N'-bis (3-methylphenyl) -1,1'-diphenyl-4,4'-diamine ( TPD) can be used.

The light emitting layer (EML) material on the surface of the hole transport layer by vacuum thermal evaporation or spin coating in a conventional manner to form a light emitting layer. In this case, the host material in the light emitting layer material used is not particularly limited, and the compound of Formula 1 is used in an amount of 0.1 to 100 mol%. The dopant used with the light emitting host in the light emitting layer material is not particularly limited, and the fluorescent dopant is IDE102, IDE105, BD-052X or C-545T ("2 as green fluorescent dopant") available from Idemitsu. , 3,6,7-tetrahydro-1,1,7,7-tetramethyl-1H, 5H, 11H-10- (2-benzothiazolyl) quinolizino- [9,9a, 1gh] coumarin ") Examples of phosphorescent dopants include tris (2-phenylpyridine) iridium (III) (Ir (ppy) ₃ ), iridium (III) bis [(4,6-difluorophenyl) pyridinato-N, C-2 '] Picolinate (FIrpic) (Chihaya Adachi etc. Appl . Phys . Lett ., 2001 , 79 , 3082 3084), platinum (II) octaethyl porphyrin (PtOEP) and TBE002 (Cobion) Can be used

An electron transport layer is formed on the surface of the light emitting layer by vacuum thermal evaporation or spin coating of an electron transport layer (ETL) material in a conventional manner. In this case, the electron transporting material used is not particularly limited, and tris (8-quinolinolato) aluminum (Alq ₃ ) may be used. Optionally, (8-quinolinolato) lithium (Liq), bis (8-hydroxy-2-methylquinol linolato) -aluminum biphenoxide (BAlq), basthocuproine (BCP) and By vacuum thermal evaporation and spin coating a hole blocking layer (HBL) material such as LiF to form a hole blocking layer between the light emitting layer and the electron transport layer and using a phosphorescent dopant in the light emitting layer, the triplet excitons or holes The phenomenon of diffusion into the transport layer can be prevented. In this case, the hole blocking layer material to be used is not particularly limited.

An electron injection layer is formed on the surface of the electron transport layer by vacuum thermal evaporation or spin coating of an electron injection layer (EIL) material in a conventional manner. In this case, the electron injection layer material to be used is not particularly limited, and materials such as LiF, Liq, Li ₂ O, BaO, NaCl and CsF may be used.

Finally, a negative electrode is formed on the surface of the electron injection layer by vacuum thermal vapor deposition in a conventional manner. At this time, the negative electrode material used is lithium (Li), aluminum (Al), aluminum-lithium (Al-Li), calcium (Ca), magnesium (Mg), magnesium-indium (Mg-In) and magnesium-silver (Mg-Ag) and the like can be used. In addition, in the case of the front emission organic field device, a transparent cathode through which light may pass may be formed using indium tin oxide (ITO) or indium zinc oxide (IZO).

The organic light emitting device according to the present invention may be manufactured in the order described above, that is, in the order of anode / hole injection layer / hole transport layer / light emitting layer / hole blocking layer / electron transport layer / electron injection layer / cathode and vice versa. It may be manufactured in the order of electron injection layer / electron transport layer / hole blocking layer / light emitting layer / hole transport layer / positive inlet layer / anode.

The fluorescent light emitting material of the present invention is excellent in electrical stability, has a high luminous efficiency and luminous luminance, and can implement a high color purity blue, and can be usefully used as a blue fluorescent light emitting material of an organic light emitting device.

Hereinafter, the present invention will be described in more detail based on the following Experimental Examples and Examples. However, the following experimental examples and examples are not intended to limit the invention only.

Example

Preparation of Compound of Formula 1

Example 1 Compound of the Invention 14 [10- (1- (9,9-dimethyl-9) H -Fluoren-2-yl) naphthalen-4-yl) -9- p -Tolylanthracene]

In a 500 mL three necked round bottom flask, 2- (4-bromo-naphthalen-1-yl) -9,9-dimethyl-9 H -fluorene (31.0 mmol, 12.2 g), 10- p -tolyl-anthracene- Add 9-boronic acid (33.6 mmol, 10.5 g) and Pd (PPh ₃ ) ₄ (1.55 mmol, 1.5 g) and 100 mL of water with 300 mL of THF and K ₂ CO ₃ (62 mmol, 8.44 g) Was added and the reaction mixture was heated to 80 ° C. and refluxed for 6 hours. After the reaction was completed, the temperature of the reaction solution was lowered to room temperature, and the reaction solvent, tetrahydrofuran (THF), was removed by distillation under reduced pressure. The solvent-free mixture was extracted with dichloromethane and recrystallized with acetone to give the title compound as a white solid.

Yield: 39% (7.1 g)

¹ H-NMR (CDCl ₃ , 400 MHz) δ (ppm) 8.17 (d, 1H), 7.91 (d, 1H), 7.85-7.75 (m, 4H), 7.72 (d, 1H), 7.67 (dd, 1H) , 7.63 (d, 1H), 7.56 (d, 2H), 7.50 (d, 2H), 7.43 (d, 4H), 7.38 (td, 2H), 7.13 (td, 2H), 7.30-7.20 (m, 4H ), 2.56 (s, 3 H), 1.61 (s, 6 H).

FD-MS: m / z = 586.54 (C ₄₆ H ₃₄ = 586.27)

Example 2 Synthesis of Compound 17 [10-phenyl-9- (1- (4- (2,2-diphenylvinyl) phenyl) naphthalen-4-yl) anthracene] of the invention

1-bromo-4- (4- (2,2-diphenylvinyl) phenyl) naphthalene instead of 2- (4-bromo-naphthalen-1-yl) -9,9-dimethyl-9 H -fluorene The title compound was obtained in the same manner as in Example 1, except that 9-phenylanthracene-10-yl-10-boron was used instead of 10- p -tolyl-anthracene-9-boronic acid.

Yield: 48% (9.4 g)

¹ H-NMR (CDCl ₃ , 400 MHz) δ (ppm) 8.07 (d, 1H), 7.74 (d, 2H), 7.68-7.55 (m, 6H), 7.54-7.46 (m, 5H), 7.45-7.29 ( m, 12H), 7.28-7.18 (m, 7H), 7.12 (s, 1H).

FD-MS: m / z = 634.73 (C ₅₀ H ₃₄ = 634.27)

Example 3: Compound 30 of the invention 30 [9,10-di (naphthalen-3-yl) -2- (1- (10- p -Tolylanthracene-9-yl) naphthalen-4-yl) anthracene]

2- (1-bromonaphthalen-4-yl) -9,10-di (naphthalene-) instead of 2- (4-bromo-naphthalen-1-yl) -9,9-dimethyl-9 H -fluorene The title compound was obtained in the same manner as in Example 1 except that 3-yl) anthracene was used.

Yield: 41% (10.5 g)

¹ H-NMR (CDCl ₃ , 400 MHz) δ (ppm) 7.88 (s, 2H), 7.84 (s, 1H), 7.75-7.52 (m, 20H), 7.38-7.30 (m, 14H), 7.14 (d, 2H), 2.34 (s, 3H).

FD-MS: m / z = 822.16 (C ₆₅ H ₄₂ = 822.33)

<Production of organic electroluminescent device>

Example 4

To the (anthracene-tolyl-fluorene-2-yl) naphthalene-4-yl) -9- p 10- (1- (9,9- dimethyl -9 H) used as a luminescent material obtained in Example 1, Compound 14 An organic light emitting diode was manufactured according to a conventional method.

First, a hole injection layer (4,4 ', 4 "-tris (N- (2-naphthyl) -N-phenylamino) -triphenylamine (2T) having a thickness of 600 mm on the ITO layer (anode) formed on the glass substrate. NATA)), 300 Å thick hole transport layer (hole transport layer material: N, N'-di (naphthalen-1-yl) -N, N'-diphenyl-benzidine (NPB)), 450 Å thick BD- 052X (Idemitsu Corporation), a light emitting layer doped with 7% (this case, BD-052X is a blue fluorescent dopant, a light-emitting host materials include 10- (1- (9,9-dimethyl -9 H obtained in example 1-fluorene -2-yl) naphthalen-4-yl) -9- p -tolylanthracene (compound 14)), a 250-kV electron transport layer (electron transport layer material: tris (8-quinolinolato) aluminum ( Alq ₃ )), an electron injection layer (electron injection layer material: lithium fluoride (LiF)) having a thickness of 10 kHz and an aluminum cathode having a thickness of 1500 kHz were sequentially deposited to fabricate an organic light emitting display device.

Example 5

Except for using the 10-phenyl-9- (1- (4- (2,2-diphenylvinyl) phenyl) naphthalen-4-yl) anthracene (Compound 17) obtained in Example 2 as a light emitting host material An organic light emitting diode was manufactured in the same manner as in Example 4.

Example 6

As a luminescent host material, 9,10-di (naphthalen-3-yl) -2- (1- (10- p -tolylanthracene-9-yl) naphthalen-4-yl) anthracene (Compound 30 obtained in Example 3) An organic light emitting display device was manufactured in the same manner as in Example 4, except for using.

Comparative example

An organic light emitting diode was manufactured according to the same method as Example 4 except for using 9,10-di (naphthalen-2-yl) anthracene (ADN) as a light emitting host material.

Test Example: Measurement of Properties of Organic Electroluminescent Device

For each of the organic light emitting diodes manufactured in Examples 4 to 6 and Comparative Examples, curves of voltage-luminance, current density-luminance, voltage-current density, and luminous efficiency-luminance, respectively, are shown in FIGS. , X and Y color coordinate-luminance curves are shown in FIGS. 6 and 7, electroluminescence spectra in FIG. 8, and time-luminance curves in FIG. 9, and these results are summarized in Table 1 below.

   -Measured at 4,000 nit

As can be seen from Table 1 and the results of FIGS. 2 to 9, the organic light emitting diodes of Examples 4 to 6 in which the light emitting layer was formed using the compounds 14, 17, and 30 of the present invention are comparative examples (ADN as a light emitting host material). Compared to the organic light emitting device, the driving voltage is relatively low, the electrical stability is excellent, the luminous efficiency and the luminous intensity are high, and the color purity is realized, and the lifespan is excellent.

1 is a cross-sectional view showing the structure of a general organic light emitting display device.

FIG. 2 is a voltage-luminance curve of an organic light emitting display device including each of Compounds 14, 17, and 30, and ADN, according to the present invention.

3 is a current density-luminance curve of an organic light emitting display device including each of Compounds 14, 17, and 30 and ADN of the present invention in a light emitting layer.

4 is a voltage-current density curve of an organic light emitting display device including each of Compounds 14, 17, and 30 and ADN of the present invention in a light emitting layer.

5 is a light emission efficiency-luminance curve of an organic light emitting display device including each of Compounds 14, 17, and 30 and ADN of the present invention in a light emitting layer.

6 and 7 are X and Y color coordinate-luminance curves of the organic light emitting diodes including the compounds 14, 17, 30, and ADN, respectively, of the present invention in the emission layer.

8 is an electroluminescence spectrum of an organic light emitting display device including each of Compounds 14, 17, and 30 and ADN of the present invention in a light emitting layer.

9 is a time-luminance (lifetime) curve of an organic light emitting display device including each of Compounds 14, 17, and 30 and ADN of the present invention in a light emitting layer.

Claims (7)

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

In Chemical Formula 1, R ¹ To Each R ³ is independently a C _1-30 alkyl group, C _2-40 alkenyl group, C _5-60 cycloalkyl group, containing or without at least one hetero atom of hydrogen, halogen, S, N, O, P and Si; C _5-60 arylalkyl group, wherein R ¹ To R ³ may be substituted or unsubstituted with F or Cl, Ar ¹ to Ar ² are each independently a C _5-50 aryl group, or a polycyclic aromatic group; A C _{5 -60} aryl group or a polycyclic aromatic group including a C _1-30 alkyl group containing or not containing at least one hetero atom of S, N, O, P and Si. The method of claim 1, R ¹ To Each R ³ is independently hydrogen, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, neo-pentyl, hexyl, heptyl, octyl, methoxy, ethoxy, cyclopentyl , Cyclohexyl, cycloheptyl, monophenylmethyl, diphenylmethyl, triphenylmethyl, trimethylsilyl, trichloromethyl, trifluoromethyl, triphenylmethyl, tetrahydropyranyl, 2-phenylisopropyl, Cl or F ego; Ar ¹ to Ar ² are each independently phenyl, 1-naphthyl, 2-naphthyl, 4-methylnaphthyl, 5-methylnaphthyl, biphenyl, 4-methylbiphenyl, 4-ethylbiphenyl, 4- Cyclohexylbiphenyl, terphenyl, 3,5-dichlorophenyl, anthryl, pyrenyl, benzofuranyl, benzothiophenyl, benzothiazolyl, quinoline, isoquinoline, fluorenyl, dimethylfluorenyl, di And phenylvinylphenyl, spirobifluorenyl, diphenylanthracenyl, dinaphthalenylanthracenyl, difluorenylanthracenyl, naphthylanthracenyl or phenanthryl. The method of claim 1, A compound according to claim 1, wherein the compound of Formula 1 is selected from compounds 1 to 80:

The method of claim 3, wherein A compound characterized in that it is selected from compound 14, compound 17 and compound 30:

In the organic light emitting device comprising an anode, a cathode and a light emitting layer between the two electrodes, An organic light emitting device in which the light emitting layer contains the compound according to any one of claims 1 to 4. The method of claim 5 The organic light emitting device of claim 1, wherein the compound of claim 1 is a light emitting host material. The method of claim 5, wherein The organic light emitting device, characterized in that the light emitting layer comprises the compound of Formula 1 in an amount of 0.1 to 100 mol%.

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