JP2011504493A - Organic electroluminescent compound and display device including the same - Google Patents

Abstract

The present invention relates to an organic electroluminescent compound and a display device using the same. The organic electroluminescent compound according to the present invention can produce an OLED device having good luminous efficiency and excellent material life characteristics, and thus a very good driving life.
[Representative] None

Description

  The present invention relates to the novel organic electroluminescent compounds shown and display elements using the same.

  The most important factor in the development of a high-efficiency and long-life organic electroluminescence (EL) device is the development of a high-performance electroluminescent material.

  In the case of blue light emission, it is advantageous from the viewpoint of light emission efficiency if the light emission wavelength is slightly shifted to the longer wavelength side. However, it is not easy to apply the material to a high quality display because it does not satisfy the pure blue color. In addition, there are problems with color purity, efficiency, and thermal stability.

In the case of blue substances, many substances have been developed and marketed since Idemitsu Kosan Co., Ltd. disclosed the development of DPVBi (compound a) in European Patent Application No. 1063869 (Patent Document 1). A system of distyryl compounds by Idemitsu Kosan, which has been known to have the highest efficiency so far, has a power efficiency of 6 lm / W and an advantageous device lifetime of over 30,000 hours. However, due to a decrease in color purity due to driving time, the lifetime is only a few thousand hours when applied to a full color display.

On the other hand, the dinaphthylanthracene compound (compound b) disclosed by Kodak in US Pat. No. 6,465,115 (Patent Document 2) is a compound specified in the claim as an HTL substance, but this is blue. It has also been used as an electroluminescent compound. However, these compounds have problems to be solved in terms of luminous efficiency and color purity.

Recently, an electroluminescent substance derivative (compound c) in a range similar to the compound b has been disclosed in International Publication No. 2006/25700 (Patent Document 3) by LG chemistry. However, the compound c similarly has a limit in luminous efficiency and color purity.

  On the other hand, as the green fluorescent substance, Alq (host) and coumarin derivatives (compound d, C545T), quinacridone derivative (compound e), DPT (compound f), etc. as dopants at concentrations of several to 20% or less. Doped systems have been developed and are widely used. However, these conventional electroluminescent materials exhibit good performance at a practical level from the viewpoint of initial luminous efficiency, but the initial efficiency is remarkably lowered, and this presents considerable problems in terms of lifetime. Thus, this material has limitations for use with larger screen high performance panels.

  This is reported to be due to the short lifetime of the Alq cationic species used as the host. In order to overcome this problem, there is a great need for the development of amphoteric hosts that simultaneously have stability for cationic and anionic species.

European Patent Application No. 1063869 US Pat. No. 6,465,115 International Publication No. 2006/25700 Pamphlet

  An object of the present invention is to solve the above-described problems, and an electroluminescent compound in which the characteristics of a host functioning as a solvent or an energy carrier in an electroluminescent material are remarkably improved as compared with those of conventional materials. Is to provide. Another object of the present invention is to provide a blue or green electroluminescent material having improved luminous efficiency and device lifetime, and an organic electroluminescent material containing the same.

（前記化学式１においては、Ｒ_１乃至Ｒ_３は、それぞれ独立して、フェニル基、Ｃ１０〜Ｃ２０の縮合多環式芳香族環であり、前記Ｒ_１乃至Ｒ_３のフェニル基またはＣ１０〜Ｃ２０の縮合多環式芳香族環には、Ｃ１〜Ｃ２０のアルキル基、Ｃ１〜Ｃ２０のアルコキシ基、ハロゲン、Ｃ５〜Ｃ７のシクロアルキル基、フェニル基または縮合多環式芳香族基がさらに置換可能である）。
また、本発明は、上記化合物を使用する表示素子に関する。 The present invention relates to an organic electroluminescent compound represented by the following chemical formula 1:

(In the chemical formula 1, R _{1 to} R ₃ are each independently a phenyl group, a C10-C20 condensed polycyclic aromatic ring, and the R _{1 to} R ₃ phenyl group or the C10-C20 The condensed polycyclic aromatic ring may be further substituted with a C1 to C20 alkyl group, a C1 to C20 alkoxy group, a halogen, a C5 to C7 cycloalkyl group, a phenyl group, or a condensed polycyclic aromatic group. ).
The present invention also relates to a display element using the above compound.

FIG. 1 shows the luminous efficiency-current density characteristics of Comparative Example 1. FIG. 2 shows the current density-voltage characteristics of the blue OLED of Example 9. FIG. 3 shows the luminous efficiency-current density characteristics of the blue OLED of Example 9. FIG. 4 shows luminous efficiency-luminance characteristics of a green OLED to which an existing electroluminescent material is applied according to Comparative Example 2. FIG. 5 shows the luminous efficiency-current density characteristics of the green OLED of Example 22. FIG. 6 shows the luminous efficiency-current density characteristics of the green OLEDs of Example 22, Comparative Example 3 and Comparative Example 4. FIG. 7 is a curve comparing the green OLED color purity of Example 22 and Comparative Example 2.

  In a broad sense, the electroluminescent substance referred to in the present invention is an organic electroluminescent element comprising a first electrode, a second electrode, and an organic substance provided between the first electrode and the second electrode. In the narrow sense, an electroluminescent material means that applied to an electroluminescent host that functions as an electroluminescent medium in an electroluminescent layer.

で表されうるが、これらの式は本発明の範囲を限定しない。 In the compounds of formula 1 according to the invention, R _{1 to} R ₃ are each independently selected from the group consisting of phenyl, naphthyl, anthryl, fluorenyl, phenanthryl, fluoranthenyl, pyrenyl, perylenyl or naphthacenyl; Phenyl, naphthyl, anthryl, fluorenyl, phenanthryl, fluoranthenyl, pyrenyl, perylenyl and naphthacenyl are C1-C20 alkyl groups, C1-C20 alkoxy groups, halogen atoms, C5-C7 cycloalkyl groups, phenyl groups or condensed poly Substituted with a cyclic aromatic group. The organic electroluminescent material represented by Chemical Formula 1 according to the present invention has the following formula:

These formulas do not limit the scope of the invention.

（前記化学式１においては、Ｒ_１乃至Ｒ_３は、それぞれ独立して、フェニル基、もしくはＣ１０〜Ｃ２０の縮合多環式芳香族環であり、前記Ｒ_１乃至Ｒ_３のフェニル基もしくはＣ１０〜Ｃ２０の縮合多環式芳香族環には、Ｃ１〜Ｃ２０のアルキル基、Ｃ１〜Ｃ２０のアルコキシ基、ハロゲン、Ｃ５〜Ｃ７のシクロアルキル基、フェニル基または縮合多環式芳香族基がさらに置換可能である）。 The present invention also provides an organic electroluminescent device comprising a first electrode; a second electrode; and one or more organic layers provided between the first electrode and the second electrode, Provided is an organic electroluminescent device in which the organic layer contains one or more compounds represented by the following chemical formula 1:

(In the chemical formula 1, R _{1 to} R ₃ are each independently a phenyl group or a C10-C20 condensed polycyclic aromatic ring, and the R _{1 to} R ₃ phenyl group or the C10-C20 In the condensed polycyclic aromatic ring, a C1-C20 alkyl group, a C1-C20 alkoxy group, a halogen, a C5-C7 cycloalkyl group, a phenyl group, or a condensed polycyclic aromatic group can be further substituted. is there).

In an organic electric field (EL) light emitting device according to the present invention, an organic layer includes an EL region, and the EL region includes one or more EL light emitting dopants together with one or more compounds represented by Formula 1 as an EL host. Including. The EL dopant applied to the organic EL device of the present invention is not particularly limited, but is exemplified by a compound represented by any one of the following chemical formulas 2 to 4:

で表される、インデノフルオレン、フルオレンまたはスピロ−フルオレンであり、
Ｒ_１１乃至Ｒ_１６は、それぞれ独立して、Ｃ１〜Ｃ２０アルキル、およびＣ１〜Ｃ５アルキル置換基を有するもしくは有しないフェニルまたはナフチルからなる群から選択され；
Ａｒ_３乃至Ａｒ_６は、それぞれ独立して、Ｃ５〜Ｃ２０の芳香族または多環式芳香族環から選択され；但し、Ａｒ_１とＡｒ_２が同じであり、Ａｒ_３とＡｒ_５が同じであって、Ａｒ_４とＡｒ_６が同じである。

ＡおよびＢは、それぞれ独立して、化学結合、または

を表し；
Ｒ_１７およびＲ_１８は、それぞれ独立して、芳香族環または２以上の芳香族環が縮合している多環式芳香族環を表し；
Ｒ_１９乃至Ｒ_２２は、それぞれ独立して、ハロゲン置換基を有するもしくは有しない直鎖または分岐鎖のＣ１〜Ｃ２０のアルキル基を表し；
Ｒ_２３乃至Ｒ_２６は、それぞれ独立して、水素もしくは芳香族基を表し；
Ａｒ_７乃至Ａｒ_１０は、それぞれ独立して、芳香族環または２以上の芳香族環が縮合されている多環式芳香族環を表す。 In Chemical Formula 3 and Chemical Formula 4, Ar ₁ and Ar ₂ are independently the following chemical formulas:

Indenofluorene, fluorene or spiro-fluorene represented by:
R _{11 to} R ₁₆ are each independently selected from the group consisting of C1-C20 alkyl, and phenyl or naphthyl with or without a C1-C5 alkyl substituent;
Ar _{3 to} Ar ₆ are each independently selected from C5 to C20 aromatic or polycyclic aromatic rings; provided that Ar ₁ and Ar ₂ are the same, and Ar ₃ and Ar ₅ are the same. Ar ₄ and Ar ₆ are the same.

A and B are each independently a chemical bond, or

Represents;
R ₁₇ and R ₁₈ each independently represents an aromatic ring or a polycyclic aromatic ring in which two or more aromatic rings are condensed;
R _{19 to} R ₂₂ each independently represents a linear or branched C1-C20 alkyl group with or without a halogen substituent;
R _{23 to} R ₂₆ each independently represents hydrogen or an aromatic group;
Ar _{7 to} Ar ₁₀ each independently represents an aromatic ring or a polycyclic aromatic ring in which two or more aromatic rings are condensed.

（前記化学式において、Ｒ_１９乃至Ｒ_２２は、メチル基またはエチル基を表す）。 The compound of Chemical Formula 3 or Chemical Formula 4 can be specifically exemplified by a compound represented by any of the following formulas:

(In the chemical formula, R _{19 to} R ₂₂ represent a methyl group or an ethyl group).

（化学式６または化学式７においては、Ｒ_２７およびＲ_２８は、それぞれ独立して、２以上の芳香族環が縮合している多環式芳香族環を表し、Ｒ_２９乃至Ｒ_３２は、それぞれ独立して、芳香族環を表し、前記Ｒ_２７乃至Ｒ_３２の各芳香族環には、Ｃ１〜Ｃ２０アルキル基がさらに置換可能である）。 The green EL compound may be exemplified by a compound represented by any one of the following chemical formulas 5 to 7:

(In Chemical Formula 6 or Chemical Formula 7, R ₂₇ and R ₂₈ each independently represent a polycyclic aromatic ring in which two or more aromatic rings are condensed, and R _{29 to} R ₃₂ are each independently And an aromatic ring, and each of the aromatic rings of R _{27 to} R ₃₂ can be further substituted with a C1 to C20 alkyl group).

のいずれかで表される化合物で例示されうる。 The compounds of Chemical Formula 6 and Chemical Formula 7 are specifically represented by the following formulas:

It can be illustrated by the compound represented by either.

Best Mode The invention will be further described with reference to the examples in relation to the process for producing the novel organic EL compounds of the invention, which examples are provided for illustration only and are provided by any means. It is not intended to limit the scope.

[Production Example] Production of Compound Represented by Chemical Formula 1

Preparation of Compound 12 9-Bromoanthracene (58.3 mmol), boronic acid derivative (Compound 11, 70.0 mmol), and tetrakis (triphenylphosphine) palladium (0) (Pd (PPh ₃ ) ₄ ) (5.8 mmol) Was dissolved in a mixed solution of toluene: ethanol (volume ratio 2: 1). To this was added 2M aqueous sodium carbonate solution, and the resulting mixture was stirred at 120 ° C. for 5 hours under reflux. Thereafter, the temperature was lowered to 25 ° C., and distilled water was added to terminate the reaction. Extraction with ethyl acetate, drying under reduced pressure, and recrystallization from tetrahydrofuran and methanol gave Compound 12.

Production of Compound 13 Compound 12 (46.0 mmol) and N-bromosuccinimide (50.6 mmol) obtained as described above were dissolved in dichloromethane under a nitrogen stream. The resulting solution was then stirred at 25 ° C. for 5 hours. Distilled water was added to terminate the reaction. Extraction with dichloromethane, drying under reduced pressure, and recrystallization from tetrahydrofuran and methanol gave Compound 13.

Preparation of Compound 2 Compound 13 (39.0 mmol) obtained as described above was dissolved in carefully purified tetrahydrofuran. The resulting solution was cooled to −78 ° C., and n-butyllithium (1.6M in hexane) (46.8 mmol) was gradually added thereto. After the mixture was stirred for 1 hour, 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (78.0 mmol) was added. The temperature was gradually raised to 25 ° C. and the mixture was stirred for 1 day. Distilled water was added to terminate the reaction, extracted with ethyl acetate, and dried under reduced pressure. Recrystallization from tetrahydrofuran and methanol gave Compound 2.

Production of Compound 3 2-Chloro-9,10-anthraquinone (29.7 mmol), Compound 2 (35.5 mmol), Tetrakis (triphenylphosphine) palladium (0) (Pd (PPh ₃ ) ₄ ) (3.0 mmol) Aliquat 336 (3.0 mmol) was dissolved in toluene. To this was added 2M aqueous potassium carbonate solution, and the resulting mixture was stirred at reflux for 3 hours. Thereafter, the temperature was lowered to 25 ° C., and distilled water was added to terminate the reaction. Extraction with ethyl acetate, drying under reduced pressure, and recrystallization from methanol and tetrahydrofuran gave Compound 3.

Preparation of Compound 6 Tetrahydrofuran was added to the bromo compound (54.3 mmol) of Compound 4 or 5, and stirred at 25 ° C. for 10 minutes to completely dissolve. After the temperature was lowered to −72 ° C., n-butyllithium (2.5 M in hexane) (65.1 mmol) was gradually added dropwise. After 1 hour, compound 3 (21.7 mmol) was added thereto, and the temperature was gradually raised to 25 ° C. The reaction mixture was stirred for 26 hours, saturated aqueous ammonium chloride was added thereto, and the resulting mixture was stirred for 1 hour. After filtration under reduced pressure, the organic layer was separated and evaporated to give compound 6.

Preparation of Compound 1 Compound 6 (21.7 mmol), potassium iodide (KI) (86.8 mmol), sodium hypophosphite monohydrate (NaH ₂ PO ₂ .H ₂ O) obtained as described above ) (130.2 mmol) was dissolved in acetic acid and the solution was stirred at reflux for 21 hours. After cooling to 25 ° C., water was added with stirring, and the produced solid was filtered off. The obtained solid was washed sequentially with methanol, ethyl acetate, and tetrahydrofuran to obtain the target compound 1 as a light ivory solid.

[Production Example 1] Production of Compound 101

Production of Compound 300 9-Bromoanthracene 15.0 g (58.3 mmol), Phenylboronic acid (Compound 200) 8.5 g (70.0 mmol), Tetrakis (triphenylphosphine) palladium (0) (Pd (PPh ₃ ) ₄ ) 6.7 g (5.8 mmol) was dissolved in a mixed solution of 300 mL of toluene and 150 mL of ethanol. To this was added 145 mL of a 2M aqueous sodium carbonate solution, and the resulting mixture was stirred at 120 ° C. for 5 hours under reflux. Thereafter, the temperature was lowered to 25 ° C., and 150 mL of distilled water was added to terminate the reaction. Extraction with 200 mL of ethyl acetate, drying under reduced pressure, and recrystallization from 20 mL of tetrahydrofuran and 300 mL of methanol gave the target compound 300 (12.0 g, 47.2 mmol).

Preparation of Compound 400 Compound 300 (11.7 g, 46.0 mmol) and 9.0 g (50.6 mmol) of N-bromosuccinimide were dissolved in 360 mL of dichloromethane under a nitrogen stream. The resulting solution was then stirred at 25 ° C. for 5 hours. 300 mL of distilled water was added to terminate the reaction. Extraction with 200 mL of dichloromethane, drying under reduced pressure, and recrystallization from 20 mL of tetrahydrofuran and 200 mL of methanol gave the target compound 400 (13.0 g, 39.0 mmol).

Preparation of Compound 500 Compound 400 (13.0 g, 39.0 mmol) was dissolved in 200 mL carefully purified tetrahydrofuran. The obtained solution was cooled to −78 ° C., and 29.3 mL (46.8 mmol) of n-butyllithium (1.6M in hexane) was gradually added thereto. After the mixture was stirred for 1 hour, 15.9 mL (78.0 mmol) of 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane was added. The temperature was gradually raised to 25 ° C., and the mixture was stirred for one day, and then 200 mL of distilled water was added to terminate the reaction. The mixture was extracted with 300 mL of ethyl acetate and dried under reduced pressure, and from 20 mL of tetrahydrofuran and 200 mL of methanol, Recrystallization gave the target compound 500 (13.5 g, 35.5 mmol).

Preparation of Compound 600 2-chloro-9,10-anthraquinone 7.2 g (29.7 mmol), compound 500 (13.5 g, 35.5 mmol), tetrakis (triphenylphosphine) palladium (0) (Pd (PPh ₃ ) ₄ ) 3.5 g (3.0 mmol) of aliquat 336 (aliquat 336) 1.4 mL (3.0 mmol) was dissolved in 300 mL of toluene. After adding 150 mL of 2M aqueous potassium carbonate solution thereto, the resulting mixture was stirred at reflux for 3 hours. Thereafter, the temperature was lowered to 25 ° C., and 100 mL of distilled water was added to terminate the reaction. Extraction with 200 mL of ethyl acetate, drying under reduced pressure, and recrystallization from 200 mL of methanol and 50 mL of tetrahydrofuran gave the target compound 600 (10.0 g, 21.7 mmol).

Preparation of Compound 700 To 11.2 g (54.3 mmol) of 2-bromonaphthalene was added 250 mL of tetrahydrofuran, and the mixture was stirred at 25 ° C. for 10 minutes to completely dissolve. After lowering the temperature to −72 ° C., 26.0 mL (65.1 mmol) of n-butyllithium (2.5 M in hexane) was gradually added dropwise. After 1 hour, compound 600 (10.0 g, 21.7 mmol) was added thereto, and the temperature was gradually raised to 25 ° C. After the reaction mixture was stirred for 26 hours, a saturated aqueous ammonium chloride solution was added thereto, and the resulting mixture was stirred for 1 hour. After filtration under reduced pressure, the organic layer was separated and evaporated to obtain the target compound 700 (15.6 g, 21.7 mmol).

Preparation of Compound 101 Compound 700 (15.6 g, 21.7 mmol), potassium iodide (KI) 14.4 g (86.8 mmol), sodium hypophosphite monohydrate (NaH ₂ PO ₂ .H ₂ O) 13.8 g (130.2 mmol) was dissolved in 250 mL of acetic acid and the solution was stirred at reflux for 21 hours. After cooling this solution to 25 degreeC, 400 mL of water was added, stirring, and the produced | generated solid was separated by filtration. The obtained solid was washed sequentially with 300 mL of methanol, 100 mL of ethyl acetate, and 50 mL of tetrahydrofuran to obtain the target compound 101 (10.0 g, 68%) having a light ivory color.
¹ HNMR (CDCl ₃ , 200 MHz) δ = 7.22 (m, 1H), 7.32-7.35 (m, 12H), 7.48-7.54 (m, 5H), 7.67-7 .73 (m, 13H), 7.89 (m, 3H)
MS / FAB: 682 (actual value) 682.85 (calculated value)

[Production Examples 2-36]
According to the procedure described in Production Example 1, organic EL compounds shown in Table 1 below were produced. The NMR data for each compound is shown in Table 2.

[Examples 1 to 13] Manufacture of an OLED element using a compound according to the present invention An OLED element was manufactured by using the electroluminescent material of the present invention.
First, the transparent electrode ITO thin film (15Ω / □) obtained from the glass for OLED (manufactured by Samsung-Corning Co., Ltd.) was subjected to ultrasonic cleaning using trichlorethylene, acetone, ethanol and distilled water in this order, and then to isopropanol. Used after storage.
Next, an ITO substrate is placed in the substrate folder of the vacuum deposition apparatus, and 4,4 ′, 4 ″ -tris (N, N- (2-naphthyl) -phenyl represented by the following chemical formula is placed in the cell of the vacuum deposition apparatus. Amino) triphenylamine (2-TNATA) was added and then evacuated until the degree of vacuum in the chamber reached 10 ⁻⁶ torr, a current was applied to the cell to evaporate 2-TNATA, and the A 60 nm thick hole injection layer was evaporated.

Next, N, N′-bis (α-naphthyl) -N, N′-diphenyl-4,4′-diamine (NPB) represented by the following chemical formula is put in another cell of the vacuum deposition apparatus, A current was applied to the cell to evaporate NPB, and a 20 nm thick hole transport layer was deposited on the hole injection layer.

After forming the hole injection layer and the hole transport layer, an electroluminescent layer was deposited thereon as follows. In one cell of the vacuum deposition apparatus, the compound according to the present invention (for example, Compound 121) was put, and in the other cell, perylene having the following structure was put as a dopant substance. The electroluminescent layer having a thickness of 35 nm was deposited on the hole transport layer by evaporating the two substances at different rates and doping perylene with a concentration of 2 to 5 mol%.

Next, as an electron transport layer, tris (8-hydroxyquinoline) -aluminum (III) (Alq) represented by the following chemical formula was deposited at a thickness of 20 nm, and as an electron injection layer, lithium quinolate ( Liq) was deposited with a thickness of 1-2 nm. Then, using another vapor deposition apparatus, an Al cathode was vapor-deposited with a thickness of 150 nm to produce an OLED.

Each material used in the OLED device was used after purification by vacuum sublimation at 10 ⁻⁶ torr.

[Examples 14 to 26] Production of an OLED device by using a compound according to the present invention As in Example 1, a hole injection layer and a hole transport layer were formed, and an EL layer was formed thereon as follows. Evaporated. A compound according to the present invention (for example, Compound 121) was placed in one cell of a vacuum deposition apparatus, and Coumarin 545T (C545T) having the following structure was placed in the other cell. The two materials were evaporated at different rates and a 35 nm thick EL layer was deposited on the hole transport layer by doping coumarin 545T (C545T) at a concentration of 2-5 mol%.

  According to the same procedure as in Example 1, after depositing an electron transport layer and an electron injection layer, an Al cathode was deposited with a thickness of 150 nm using another vapor deposition apparatus to produce an OLED.

[Comparative Example 1] Production of OLED device by using conventional EL material A hole injection layer and a hole transport layer were formed as in Example 1. In one cell of the vacuum deposition apparatus, dinaphthylanthracene (DNA) was put as a blue EL material, and perylene was put in another cell as another blue EL material. An electroluminescent layer having a thickness of 35 nm was deposited on the hole transport layer at a deposition rate of 100: 1.

  In accordance with the same procedure as in Example 1, an electron transport layer and an electron injection layer were vapor-deposited, and then an Al cathode was vapor-deposited with a thickness of 150 nm using another vapor deposition apparatus to produce an OLED.

[Comparative Example 2] Manufacture of an OLED device by using a conventional EL material As in Example 1, a hole injection layer and a hole transport layer were formed. Tris (8-hydroxyquinoline) -aluminum (III) (Alq) was placed in the other cell of the vapor deposition apparatus as an EL host material, and Coumarin 545T (C545T) was placed in the other cell. An EL layer having a thickness of 30 nm was deposited on the hole transport layer by evaporating and doping two substances at different rates. The doping concentration is preferably 2 to 5 mol% based on Alq.

  In accordance with the same procedure as in Example 1, an electron transport layer and an electron injection layer were vapor-deposited, and then an Al cathode was vapor-deposited with a thickness of 150 nm using another vapor deposition apparatus to produce an OLED.

[Comparative Example 3] Manufacture of an OLED element by using a conventional EL material As in Example 1, a hole injection layer and a hole transport layer were formed. Dinaphthylanthracene (DNA) was placed as a blue EL material in the other cell of the vacuum deposition apparatus, and Coumarin 545T (C545T) was placed in the other cell. An EL layer having a thickness of 30 nm was deposited on the hole transport layer by evaporating and doping two substances at different rates. The doping concentration was preferably 2 to 5 mol% based on Alq.

[Comparative Example 4] Manufacture of OLED Device by Using Conventional EL Material A hole injection layer and a hole transport layer were formed as in Example 1. Compound A disclosed in US Patent Application Publication No. 2006046097A1 having the following structure as a blue EL substance was placed in the other cell of the vacuum deposition apparatus, and Coumarin 545T (C545T) was placed in another cell. An EL layer having a thickness of 30 nm was deposited on the hole transport layer by evaporating and doping two substances at different rates. The doping concentration was preferably 2 to 5 mol% based on Alq.

  According to the same procedure as in Example 1, after depositing an electron transport layer and an electron injection layer, an Al cathode was deposited with a thickness of 150 nm using another vapor deposition apparatus to produce an OLED.

[Experimental Example 1] Blue EL characteristics of manufactured OLED element OLED manufactured from Examples 1 to 13 containing an organic EL compound according to the present invention, and manufactured from Comparative Example 1 containing a conventional electroluminescent compound the blue light-emitting efficiency of the OLED, individually, measured at 500 cd / ^{m 2} and 2,000 cd / ^{m 2,} and the results are shown in Table 3.

  Table 3 above shows the results of applying the substance of the present invention to a blue EL device. As can be seen from Table 3, the luminous efficiency of the EL material of the present invention was 5.26-6.30 cd / A at low brightness and 4.80-5.88 cd / A at high brightness, Thus, the luminous efficiency of the EL material of Comparative Example 1 was 4.45 cd / A and 3.6 cd / A at low luminance and high luminance, respectively. Therefore, the EL device using the organic EL compound according to the present invention showed a luminous efficiency higher by 1.5 cd / A or more than that of the comparative example. In particular, at high brightness, an improvement in luminous efficiency of 2 cd / A or more was confirmed for each compound.

  Furthermore, with respect to color purity, a slight improvement was observed when the host material of the present invention was applied. As described above, the result of simultaneously improving the luminous efficiency and the color purity proves that the EL material of the present invention has excellent characteristics.

  FIG. 1 shows the luminous efficiency-current density characteristics of Comparative Example 1 using the conventional EL material DNA: perylene; FIGS. 2 and 3 show Example 9 using the compound 121 of the present invention as the EL material. Current density-voltage characteristics and luminous efficiency-current density characteristics are shown. From the results shown in the figure, a significant improvement in characteristics was confirmed.

[Experimental Example 2] Green EL characteristics of manufactured OLED element OLEDs manufactured from Examples 14 to 26 containing an organic EL compound according to the present invention and OLEDs manufactured from Comparative Example 1 containing a conventional electroluminescent compound The green luminous efficiency was measured individually at 5,000 cd / m ² and 20,000 cd / m ² , and the results are shown in Table 4.

  Table 4 above shows the results of the characteristics of the green EL device to which the substance of the present invention was applied. Similar to the blue EL element of Experimental Example 1, characteristics superior to those of conventional EL materials were confirmed at low luminance and high luminance.

  An efficiency improvement of 70% or more with respect to the Alq host of Comparative Example 2 and 40% or more with respect to the conventional host of Comparative Example 3 was confirmed. This result shows overcoming the limitations of conventional green EL materials. In particular, significant performance improvements at high brightness allow this compound to be put into practical use for large screen OLEDs that require high brightness or 2 inch class passive OLEDs that require extreme properties. It is estimated that

  There was no significant difference in terms of chromaticity coordinates. Therefore, it can be said that the EL material of the present invention having improved luminous efficiency while maintaining color purity is an epoch-making invention that exceeds existing materials by one step.

  FIG. 4 shows the luminous efficiency-luminance characteristics of Comparative Example 2 using Alq: C545T, which is a conventional green EL material, and FIG. 5 shows the green EL of Example 22 using Compound 121 according to the present invention as the EL material. The light emission efficiency-current density characteristics of the device are shown. FIG. 6 shows the luminous efficiency-current density characteristics of the green EL elements of Comparative Example 3 and Comparative Example 4 using a conventional EL material, and Example 22 using the compound 121 according to the present invention as the EL material.

  The EL material of the present invention was applicable to both blue OLED and green OLED, and showed excellent results in terms of performance. This result shows the very conspicuous properties of excellent EL materials. The invention of a material having such properties provides the attendant consequences of simplifying the OLED panel structure and consequently reducing the cost of manufacturing the OLED. This excellent property can lead to innovative results in the development of the OLED field.

  FIG. 7 shows a comparison between the color purity of the green EL device of Example 22 and the green EL device of Comparative Example 2 using the compound 121 of the present invention as the EL material. The EL material of the present invention showed good EL color characteristics because it does not show a significant difference compared to the conventional pure green EL material. In the EL spectrum of the EL device of Example 22, a typical green EL peak at 520 nm was confirmed. This indicates the fact that the organic EL compound of the present invention having blue EL characteristics has very good electrical characteristics that bring out the characteristics of the EL dopant to the maximum level.

  In particular, the superior lifetime properties of the material according to the present invention compared to the conventional EL material, in contrast to the conventional material with good electronic conductivity, the maximum advantage of the material of the present invention. Achieve.

  By introducing the 10th position of 9-arylanthryl at the 2nd position of anthracene, the effect of superposition of intermolecular orbitals is improved, and the energy level relationship with the dopant is more advantageous, and the simple conventional 9 , 10-diarylanthracene structure is complemented.

  The electroluminescent compounds according to the present invention have good luminous efficiency and excellent lifetime characteristics of the material, and thus can produce OLED devices with very good driving lifetime.

Claims (9)

Organic electroluminescent material represented by the following chemical formula 1:

(In Chemical Formula 1, R _{1 to} R ₃ each independently represents a phenyl group or a C10-C20 condensed polycyclic aromatic ring, and the R _{1 to} R ₃ phenyl group or the C10-C20 condensed polycyclic ring. The cyclic aromatic ring can be further substituted with a C1 to C20 alkyl group, a C1 to C20 alkoxy group, a halogen, a C5 to C7 cycloalkyl group, a phenyl group, or a condensed polycyclic aromatic group). R _{1 to} R _{3 in} Formula 1 are each independently selected from the group consisting of phenyl, naphthyl, anthryl, fluorenyl, phenanthryl, fluoranthenyl, pyrenyl, perylenyl, or naphthacenyl; optionally phenyl, naphthyl, anthryl, fluorenyl , Phenanthryl, fluoranthenyl, pyrenyl, perylenyl and naphthacenyl are substituted with C1-C20 alkyl group, C1-C20 alkoxy group, halogen atom, C5-C7 cycloalkyl group, phenyl group or condensed polycyclic aromatic group The organic electroluminescent material according to claim 1, wherein The following chemical formula:

The organic electroluminescent material according to claim 2, which is selected from the compounds represented by: An organic electroluminescent element comprising: a first electrode; a second electrode; and one or more organic layers provided between the first electrode and the second electrode,
Organic electroluminescent device in which the organic layer contains one or more compounds represented by the following chemical formula 1:

(In Formula 1, each of R _{1 to} R ₃ independently represents a phenyl group or a C10-C20 condensed polycyclic aromatic ring, and the R _{1 to} R ₃ phenyl group or the C10-C20 condensed polycyclic ring. The cyclic aromatic ring can be further substituted with a C1 to C20 alkyl group, a C1 to C20 alkoxy group, a halogen, a C5 to C7 cycloalkyl group, a phenyl group, or a condensed polycyclic aromatic group).   The organic electroluminescent device according to claim 4, wherein the organic layer includes an electroluminescent region, and the electroluminescent region includes one or more compounds represented by Chemical Formula 1 and one or more electroluminescent dopants. The organic electroluminescent element according to claim 5, wherein the electroluminescent dopant is selected from compounds represented by any one of the following chemical formulas 2 to 4:

(In the formula, Ar ₁ and Ar ₂ are represented by the following chemical formulas:

Selected from indenofluorene, fluorene and spiro-fluorene;
R _{11 to} R ₁₆ are each independently selected from the group consisting of C1-C20 alkyl, and phenyl or naphthyl with or without a C1-C5 alkyl substituent;
Ar _{3 to} Ar ₆ are each independently selected from C5 to C20 aromatic or polycyclic aromatic rings; provided that Ar ₁ and Ar ₂ are the same, and Ar ₃ and Ar ₅ are the same. And Ar ₄ and Ar ₆ are the same;

A and B are each independently a chemical bond or an atomic group

Represents;
R ₁₇ and R ₁₈ each independently represents an aromatic ring or a polycyclic aromatic ring in which two or more aromatic rings are condensed;
R _{19 to} R ₂₂ each independently represents a linear or branched C1-C20 alkyl group with or without a halogen substituent;
R _{23 to} R ₂₆ each independently represents hydrogen or an aromatic group;
Ar _{7 to} Ar ₁₀ each independently represents an aromatic ring or a polycyclic aromatic ring in which two or more aromatic rings are condensed). The organic electroluminescent device according to claim 6, wherein the electroluminescent dopant is selected from compounds represented by any of the following formulae:

(In the chemical formula, R _{19 to} R ₂₂ represent a methyl group or an ethyl group). The organic electroluminescent device according to claim 5, wherein the electroluminescent dopant is selected from compounds represented by any one of the following chemical formulas 5 to 7:

(Wherein R ₂₇ and R ₂₈ each independently represent a polycyclic aromatic ring in which two or more aromatic rings are condensed; R _{29 to} R ₃₂ are each independently an aromatic ring) the expressed; each aromatic ring of said _{R 27} or _{R 32} can be further substituted by an alkyl group having C1 to C20). The electroluminescent dopant is represented by the following formula:

The organic electroluminescent element according to claim 8, wherein the organic electroluminescent element is selected from compounds represented by any one of:

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