KR102146386B1 - Composistion for organic electroluminescent device and novel organic electroluminescent and organic electroluminescent device comprising the same - Google Patents

Abstract

The present invention relates to a composition for an organic light-emitting device light-emitting layer, a novel organic light-emitting compound, and an organic light-emitting device including the same.

Description

Composition for an organic light-emitting device emission layer, a novel organic light-emitting compound, and an organic light-emitting device including the same {COMPOSISTION FOR ORGANIC ELECTROLUMINESCENT DEVICE AND NOVEL ORGANIC ELECTROLUMINESCENT AND ORGANIC ELECTROLUMINESCENT DEVICE COMPRISING THE SAME}

The present invention relates to a composition for an organic light-emitting device emission layer, a novel organic light-emitting compound, and an organic light-emitting device comprising the same.

The organic light-emitting device is a device that emits light while electrons and holes form a pair and then disappear when charge is injected into an organic material layer formed between an electron injection electrode (cathode) and a hole injection electrode (anode). Not only can the device be formed on a flexible transparent substrate such as plastic, but it can also be driven at a lower voltage (less than 10V) compared to a plasma display panel or an inorganic EL display. In addition, it has the advantage of relatively low power consumption and excellent color.

Typical organic light emitting devices include a substrate, an anode, a hole injection layer that accepts holes from the anode, a hole transport layer that transports holes, a light emitting layer where holes and electrons combine to emit light, an electron transport layer that receives electrons from the cathode and transfers them to the light emitting layer, And a cathode. In some cases, a light-emitting layer may be formed by doping a small amount of fluorescent or phosphorescent dye on the electron transport layer or hole transport layer without a separate light-emitting layer. When using a polymer, the hole transport layer, the light-emitting layer, and the electron transport layer are generally used as one. Polymers can run at the same time. The organic material layers between the two electrodes are formed by vacuum deposition, spin coating, inkjet printing, or roll coating, and a separate electron injection layer is sometimes inserted for efficient injection of electrons from the cathode.

The most important factor determining luminous efficiency in an organic light emitting device is a light emitting material. Fluorescent luminescent materials are currently widely used as luminescent materials, but development of phosphorescent luminescent materials is one of the best ways to theoretically improve luminous efficiency up to 4 times. Until now, iridium (III) complex series are widely known as phosphorescent materials, and materials such as (acac)Ir(btp) ₂ , Ir(ppy) ₃ and Firpic are known for each RGB. As a phosphorescent material, CBP ((4,4′-N, N′-dicarbazole) biphenyl) is the most widely known, and BCP (Bathocuproine) and BAlq ([Bis(2-methyl-8-quinolinolato-N1, O8)-(1,1'-Biphenyl-4-olato)aluminum]) is a high-efficiency OLED that applies a hole blocking layer, and pioneers in Japan have developed high-performance OLEDs using BAlq derivatives as a host. There is a bar.

However, organic light emitting devices using conventional phosphorescent materials have significantly higher current efficiency (cd/A) than devices using fluorescent materials, but when materials such as BAlq and CBP are used as the host of phosphorescent materials, fluorescent materials are used. There is no significant advantage in terms of power efficiency (lm/w) because the driving voltage is higher than the used device. In addition, since the lifespan of the device has not been satisfactory, the development of a more stable and high-performance host material is required.

Accordingly, the present inventors have repeatedly studied the light-emitting host material in consideration of the problems of the prior art, and as a result, organic light-emitting compounds, which are novel phosphorescent host compounds that can greatly improve luminous efficiency, stability, and device life, and organic light-emitting compounds using the same. The present invention was completed to provide a device.

An object of the present invention is to provide a novel organic light-emitting compound.

In addition, another object of the present invention is to provide an organic light-emitting compound and an organic light-emitting device including the same, which can significantly reduce power consumption because it can be driven by a low voltage by using a novel organic light-emitting compound as a host material of the light-emitting layer. To provide.

In addition, another object of the present invention is to provide an organic light emitting device that can significantly improve current efficiency and has excellent light emitting characteristics.

The composition for an organic light-emitting device emission layer according to the present invention for achieving the above object includes a dopant and a host, and the host includes an organic light-emitting compound represented by Formula 1 below.

[Formula 1]

In Formula 1,

The Ar ₁ , Ar ₂ , Ar ₃ and Ar ₄ are each independently a C ₆ -C ₂₀ aryl group, and the C ₆ -C ₂₀ aryl group C ₁ -C ₁₀ alkyl group and C ₁ -C ₁₀ alkoxy It may be further substituted with any one or two or more substituents selected from the group,

R ₁ and R ₂ are each independently hydrogen, a C ₁ -C ₁₀ alkyl group or a C ₁ -C ₁₀ alkoxy group,

에서 선택되는 어느 하나 또는 둘 이상의 치환기로 더 치환될 수 있으며, 상기 R₃은 직접결합 또는 C₁-C₅인 알킬렌기이다.A is a C ₁ -C ₂₀ alkylene group, -CH ₂ -included in the alkylene group may be substituted with -O- or -S-, and the alkylene group of A is a C ₁ -C ₁₀ alkyl group And

It may be further substituted with any one or two or more substituents selected from, and R ₃ is a direct bond or a C ₁ -C ₅ alkylene group.

According to an aspect of the present invention, in terms of color purity and electrical stability, the Ar ₁ , Ar ₂ , Ar ₃ and Ar ₄ of the organic light-emitting compound represented by Formula 1 are each independently C ₆ -C ₂₀ Is an aryl group,

에서 선택되는 어느 하나 또는 둘 이상의 치환기로 더 치환될 수 있으며, 상기 R₃은 직접결합 또는 C₁-C₅인 알킬렌기일 수 있다.The R ₁ and R ₂ are hydrogen, A is a C ₁ -C ₂₀ alkylene group, -CH ₂ -included in the alkylene group may be substituted with -O- or -S-, The alkylene group is a C ₁ -C ₁₀ alkyl group and

It may be further substituted with any one or two or more substituents selected from, and R ₃ may be a direct bond or a C ₁ -C ₅ alkylene group.

According to an aspect of the present invention, in terms of interfacial properties with an electrode due to improved solubility and heat resistance in an organic solvent, the Ar ₁ , Ar ₂ , Ar ₃ and Ar ₄ of the organic light-emitting compound represented by Formula 1 are each independently a C ₁ -C ₁₀ alkyl groups and C ₁ -C ₁₀ alkoxy group substituted with one or more C ₆ -C ₂₀ aryl group with two or more substituents selected from,

The R ₁ and R ₂ are each independently selected from hydrogen, a C ₁ -C ₅ alkyl group and a C ₁ -C ₅ alkoxy group,

에서 선택되는 어느 하나 또는 둘 이상의 치환기로 더 치환될 수 있으며, 상기 Ar₅ 및 Ar₆은 각각 독립적으로 C₆-C₂₀인 아릴기이고, 상기 C₆-C₂₀인 아릴기는 C₁-C₁₀인 알킬기 및 C₁-C₁₀인 알콕시기에서 선택되는 어느 하나 또는 둘 이상의 치환기로 더 치환될 수 있으며, 상기 R₃은 직접결합 또는 C₁-C₅인 알킬렌기일 수 있다.A is a C ₁ -C ₂₀ alkylene group, -CH ₂ -included in the alkylene group may be substituted with -O- or -S-, and the alkylene group of A is a C ₁ -C ₁₀ alkyl group And

It may be further substituted with any one or two or more substituents selected from, wherein Ar ₅ and Ar ₆ are each independently a C ₆ -C ₂₀ aryl group, and the C ₆ -C ₂₀ aryl group C ₁ -C ₁₀ It may be further substituted with any one or two or more substituents selected from a phosphorus alkyl group and a C ₁ -C ₁₀ alkoxy group, and R ₃ may be a direct bond or a C ₁ -C ₅ alkylene group.

The dopant according to an aspect of the present invention is any one or two selected from Ir, Pt, Os, Ti, Zr, Hf, Eu, Tb, Tm, Fe, Co, Ni, Ru, Rh, Re, Pd and P It may include a metal complex including the above metal.

The host and the dopant according to an aspect of the present invention may be included in a weight ratio of 70:30 to 99:1.

In addition, the present invention is to provide an organic light-emitting compound as described above included in the composition for an organic light-emitting device emission layer.

Formula 1 according to an aspect of the present invention may be represented by various structural formulas.

The organic light-emitting device according to the present invention includes an organic light-emitting compound.

The organic light emitting device according to an aspect of the present invention includes a first electrode, a second electrode, and one or two or more organic material layers interposed between the first electrode and the second electrode, and the organic material layer is the organic light emitting compound. It may include a light-emitting layer containing.

The organic light-emitting compound according to an aspect of the present invention may be included as a host of an emission layer.

The organic light-emitting compound according to the present invention is bonded to a moiety having a diarylamine group in the second substituent of the carbazole group and an alkylene group linking group, and when included as a host material of the emission layer of an organic light-emitting device, current superior to conventional materials There is an advantage in that it can have efficiency and can significantly improve light-emitting characteristics and device life.

In addition, the organic light-emitting compound according to the present invention has high electron transfer efficiency, so it not only prevents crystallization during device fabrication, but also has good layer formation, thereby improving the current characteristics of the device, realizing a low driving voltage, and inducing an increase in current efficiency. There is an advantage of manufacturing an organic light emitting device with improved power consumption.

1 is a graph showing current density (㎃/㎠) and luminance (cd/m2) at 0 to 15V of an organic light-emitting device including an organic light-emitting compound according to an embodiment of the present invention.
2 is a graph showing current efficiency (cd/A) versus luminance (cd/m2) of an organic light-emitting device including an organic light-emitting compound according to an embodiment of the present invention.

Hereinafter, a composition for an organic light-emitting device light-emitting layer, a novel organic light-emitting compound, and an organic light-emitting device including the same according to the present invention will be described in more detail through the following examples. However, the following examples are only a reference for describing the present invention in detail, and the present invention is not limited thereto, and may be implemented in various forms.

In addition, unless otherwise defined, all technical and scientific terms have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. The terms used in the description herein are merely for effectively describing specific embodiments, and are not intended to limit the invention.

The present invention relates to a composition for an organic light-emitting device emission layer, a novel organic light-emitting compound, and an organic light-emitting device comprising the same.

An organic light-emitting device capable of realizing excellent luminous efficiency with excellent current efficiency and brightness, including a novel organic light-emitting compound preferably bonded to a moiety having a diarylamine group at the second substitution position of the carbazole group through an alkylene group linking group It is about.

The present invention will be described in detail as follows.

The composition for an organic light-emitting device emission layer according to the present invention includes a dopant and a host, and the host is an organic light-emitting compound represented by Formula 1 below.

[Formula 1]

In Formula 1,

The Ar ₁ , Ar ₂ , Ar ₃ and Ar ₄ are each independently a C ₆ -C ₂₀ aryl group, and the C ₆ -C ₂₀ aryl group C ₁ -C ₁₀ alkyl group and C ₁ -C ₁₀ alkoxy It may be further substituted with any one or two or more substituents selected from the group,

R ₁ and R ₂ are each independently hydrogen, a C ₁ -C ₁₀ alkyl group or a C ₁ -C ₁₀ alkoxy group,

에서 선택되는 어느 하나 또는 둘 이상의 치환기로 더 치환될 수 있으며, 상기 R₃은 직접결합 또는 C₁-C₅인 알킬렌기이다.A is a C ₁ -C ₂₀ alkylene group, -CH ₂ -included in the alkylene group may be substituted with -O- or -S-, and the alkylene group of A is a C ₁ -C ₁₀ alkyl group And

It may be further substituted with any one or two or more substituents selected from, and R ₃ is a direct bond or a C ₁ -C ₅ alkylene group.

The composition for an organic light-emitting device emission layer according to the present invention hosts an organic light-emitting compound in which a diarylamine group is substituted at the second substitution position of a carbazole group as shown in Figure 1 below, and is connected to an alkylene group as described above with a linker. It is included as an ingredient.

[Picture 1]

As described above, the diarylamine group is substituted at the 2nd substitution position of the carbazole group, and all the alkylene groups are satisfied in the linking group, so that easy electron transfer is possible, thereby enhancing the driving voltage to have high electron density, and current efficiency. The luminous efficiency of the lamp can be remarkably improved.

According to an aspect of the present invention, in terms of improving color purity and electrical stability, the Ar ₁ , Ar ₂ , Ar ₃ and Ar ₄ of the organic light-emitting compound represented by Formula 1 are each independently C ₆ -C ₂₀ Is a phosphorus aryl group,

에서 선택되는 어느 하나 또는 둘 이상의 치환기로 더 치환될 수 있으며, 상기 R₃은 직접결합 또는 C₁-C₅인 알킬렌기일 수 있다.The R ₁ and R ₂ are hydrogen, A is a C ₁ -C ₂₀ alkylene group, -CH ₂ -included in the alkylene group may be substituted with -O- or -S-, The alkylene group is a C ₁ -C ₁₀ alkyl group and

It may be further substituted with any one or two or more substituents selected from, and R ₃ may be a direct bond or a C ₁ -C ₅ alkylene group.

In terms of improving color purity and electrical stability, preferably Ar ₁ , Ar ₂ , Ar ₃ and Ar ₄ are each independently C ₆ -C ₂₀ aryl group,

에서 선택되는 어느 하나 또는 둘 이상의 치환기로 더 치환될 수 있으며, 상기 R₃은 C₁-C₅인 알킬렌기일 수 있다.The R ₁ and R ₂ are hydrogen, A is a C ₁ -C ₁₀ alkylene group, -CH ₂ -included in the alkylene group may be substituted with -O- or -S-, The alkylene group is a C ₁ -C ₅ alkyl group and

It may be further substituted with any one or two or more substituents selected from, and R ₃ may be a C ₁ -C ₅ alkylene group.

In terms of improving color purity and electrical stability, more preferably the Ar ₁ , Ar ₂ , Ar ₃ and Ar ₄ are each independently a C ₆ -C ₂₀ aryl group,

The R ₁ and R ₂ are hydrogen, and A may be a C ₁ -C ₅ alkylene group, and the alkylene group of A may be further substituted with a C ₁ -C ₃ alkyl group.

According to an aspect of the present invention, a diarylamine group is substituted at the 2nd substitution position of the carbazole group as described above. When a substituent is not included in the diarylamine group, luminous efficiency such as current efficiency can be remarkably improved, and color purity and electrical stability can be further improved.

According to an aspect of the present invention, in terms of interfacial properties with an electrode due to improved solubility and heat resistance in an organic solvent, the Ar ₁ , Ar ₂ , Ar ₃ and Ar ₄ of the organic light emitting compound represented by Formula 1 are each independently with a C ₁ -C ₁₀ alkyl groups and C ₁ -C ₁₀ alkoxy group in which one or more of the substituted C ₆ -C ₂₀ aryl group, two or more substituents selected from,

The R ₁ and R ₂ are each independently selected from hydrogen, a C ₁ -C ₅ alkyl group and a C ₁ -C ₅ alkoxy group,

에서 선택되는 어느 하나 또는 둘 이상의 치환기로 더 치환될 수 있으며, 상기 Ar₅ 및 Ar₆은 각각 독립적으로 C₆-C₂₀인 아릴기이고, 상기 C₆-C₂₀인 아릴기는 C₁-C₁₀인 알킬기 및 C₁-C₁₀인 알콕시기에서 선택되는 어느 하나 또는 둘 이상의 치환기로 더 치환될 수 있으며, 상기 R₃은 직접결합 또는 C₁-C₅인 알킬렌기일 수 있다.A is a C ₁ -C ₂₀ alkylene group, -CH ₂ -included in the alkylene group may be substituted with -O- or -S-, and the alkylene group of A is a C ₁ -C ₁₀ alkyl group And

It may be further substituted with any one or two or more substituents selected from, wherein Ar ₅ and Ar ₆ are each independently a C ₆ -C ₂₀ aryl group, and the C ₆ -C ₂₀ aryl group C ₁ -C ₁₀ It may be further substituted with any one or two or more substituents selected from a phosphorus alkyl group and a C ₁ -C ₁₀ alkoxy group, and R ₃ may be a direct bond or a C ₁ -C ₅ alkylene group.

In terms of the interface properties with the electrode due to improved solubility and heat resistance in organic solvents, the Ar ₁ , Ar ₂ , Ar ₃ and Ar ₄ of the organic light-emitting compound represented by Formula 1 are each independently C ₁ -C _{It is} a C ₆ -C ₂₀ aryl group further substituted with any one or two or more substituents selected from a ₅ phosphorus alkyl group and a C ₁ -C ₅ alkoxy group,

The R ₁ and R ₂ are each independently selected from hydrogen, a C ₁ -C ₃ alkyl group and a C ₁ -C ₃ alkoxy group,

에서 선택되는 어느 하나 또는 둘 이상의 치환기로 더 치환될 수 있으며, 상기 Ar₅ 및 Ar₆은 각각 독립적으로 C₆-C₂₀인 아릴기이고, 상기 C₆-C₂₀인 아릴기는 C₁-C₅인 알킬기 및 C₁-C₅인 알콕시기에서 선택되는 어느 하나 또는 둘 이상의 치환기로 더 치환될 수 있으며, 상기 R₃은 직접결합 또는 C₁-C₅인 알킬렌기일 수 있다.A is a C ₁ -C ₁₀ alkylene group, -CH ₂ -included in the alkylene group may be substituted with -O- or -S-, and the alkylene group of A is a C ₁ -C ₅ alkyl group And

It may be further substituted with any one or two or more substituents selected from, wherein Ar ₅ and Ar ₆ are each independently a C ₆ -C ₂₀ aryl group, and the C ₆ -C ₂₀ aryl group C ₁ -C ₅ It may be further substituted with any one or two or more substituents selected from a phosphorus alkyl group and a C ₁ -C ₅ phosphorus alkoxy group, and R ₃ may be a direct bond or a C ₁ -C ₅ alkylene group.

In terms of interfacial properties with the electrode due to improved solubility and heat resistance in organic solvents, more preferably, Ar ₁ , Ar ₂ , Ar ₃ and Ar ₄ of the organic light-emitting compound represented by Formula 1 are each independently C _1- A C ₆ -C ₂₀ aryl group further substituted with any one or two or more substituents selected from a C ₃ alkyl group and a C ₁ -C ₃ alkoxy group,

The R ₁ and R ₂ are each independently selected from hydrogen, a C ₁ -C ₃ alkyl group and a C ₁ -C ₃ alkoxy group, and A may be a C ₁ -C ₅ alkylene group.

According to an aspect of the present invention, a diarylamine group is substituted at the 2nd substitution position of the carbazole group as described above. In the case of including a substituent in the diarylamine group, not only can the luminous efficiency such as current efficiency be remarkably improved, but also can be easily dissolved in an organic solvent, so that a large area of luminescence can be maintained. The interface characteristics are very good.

According to an aspect of the present invention, even when oxygen or sulfur is included in the alkylene group of the linking group, luminous efficiency such as current efficiency can be remarkably improved.

The "alkyl" refers to a monovalent organic radical having one bonding site derived from a straight-chain or pulverized hydrocarbon having 1 to 10 carbon atoms. The "alkylene" refers to a divalent organic radical having two bonding positions derived from a straight-chain hydrocarbon having 1 to 20 carbon atoms.

The "aryl" is an organic radical derived from an aromatic hydrocarbon by the removal of one hydrogen, suitably a single or fused ring containing 4 to 7, preferably 5 or 6 ring atoms in each ring It includes a system, and includes a form in which a plurality of aryls are connected by a single bond. Specific examples include, but are not limited to, phenyl, naphthyl, and biphenyl. The “arylene” refers to an aromatic ring divalent organic radical derived from an aromatic hydrocarbon.

According to an aspect of the present invention, the Ar ₁ , Ar ₂ , Ar ₃ , Ar ₄ , Ar ₅ and Ar ₆ of the C ₆ -C ₂₀ aryl groups are each independently specific examples, for example, phenyl, diphenyl, naphthyl, methylphenyl, ethylphenyl, methoxyphenyl, ethoxyphenyl, methylnaphthyl , Ethyl naphthyl, methoxy naphthyl or ethoxy naphthyl may be selected, but is not limited thereto.

The diarylamine group may be selected from a specific example, preferably a diphenylamine group, a dinaphthylamine group, and a phenylnaphthylamine group.

According to an aspect of the present invention, the dopant is not particularly limited as long as a known dopant material is used, and a known dopant may be selected and used as necessary. The dopant may include at least one of a fluorescent dopant and a phosphorescent dopant. The phosphorescent dopant is a compound capable of emitting light from triplet excitons, and is not particularly limited as long as it emits light from triplet excitons, and Ir, Pt, Os, Ti, Zr, Hf, Eu, Tb, Tm, Fe, Co, Ni, It may be a metal complex including any one or two or more metals selected from Ru, Rh, Re, Pd, and P, but is not limited thereto.

Preferably, the metal complex may be selected from an iridium complex and a platinum complex. In particular, a porphyrin metal complex or an ortho metallized metal complex is preferred. As the porphyrin metal complex, a porphyrin platinum complex is preferable. There are various ligands that form the ortho-metallized metal complex of the phosphorescent dopant, but preferred ligands include 2-phenylpyridine derivatives, 7,8-benzoquinoline derivatives, 2-(2-thienyl)pyridine derivatives, and 2-(1- It may be any one or two or more selected from naphthyl) pyridine derivatives and 2-phenylquinoline derivatives. These derivatives may have a substituent as necessary. As an auxiliary ligand, any one selected from acetylacetonato, picric acid, or the like, or two or more ligands other than the above ligands may be further provided. Specifically, for example, bisthienylpyridine acetylacetonate iridium (bisthienylpyridine acetylacetonate Iridium), bis (benzothienylpyridine) acetylacetonate iridium {bis (benzothienylpyridine) acetylacetonate Iridium}, bis (2-phenylbenzothiazole) acetylaceto Nate iridium {Bis(2-phenylbenzothiazole)acetylacetonate Iridium}, bis(1-phenylisoquinoline) iridium acetylacetonate {bis(1-phenylisoquinoline) Iridium acetylacetonate}, tris(1-phenylisoquinoline) iridium {tris(1- phenylisoquinoline)Iridium}, tris (phenylpyridine) iridium {tris (phenylpyridine) Iridium}, tris (2-biphenylpyridine) iridium {tris (2-phenylpyridine) Iridium}, tris (3-biphenylpyridine) iridium {tris( 3-biphenylpyridine)Iridium}, tris(4-biphenylpyridine)Iridium{tris(4-biphenylpyridine)Iridium} and tris[2-(p-tolyl)pyridine]iridium(III){tris[2-(p-tolyl) )pyridine]iridium(III)}, etc. may be any one or two or more selected from, but is not limited thereto.

According to an aspect of the present invention, the host and the dopant may be included in a weight ratio of 70:30 to 99:1. Preferably, 80:20 to 99:1 weight ratio, more preferably 90:10 to 99:1 weight ratio may be included, but is not limited thereto. When provided in the above amount, the organic light emitting device including the same may have high efficiency, long life, and high color purity.

According to an aspect of the present invention, the composition for an organic light-emitting device emission layer may be formed as an emission layer on another organic material layer by any one or two or more methods selected from a vacuum deposition method and a spin coating method, but is not limited thereto.

The organic light-emitting compound according to the present invention is provided as described above with the organic light-emitting compound included in the composition for the light-emitting layer of the organic light-emitting device.

According to an aspect of the present invention, in terms of improving color purity and electrical stability, the Ar ₁ , Ar ₂ , Ar ₃ and Ar ₄ of the organic light-emitting compound represented by Formula 1 are each independently C ₆ -C ₂₀ Is a phosphorus aryl group,

Wherein R ₁ and R ₂ are hydrogen,

에서 선택되는 어느 하나 또는 둘 이상의 치환기로 더 치환될 수 있으며, 상기 R₃은 직접결합 또는 C₁-C₅인 알킬렌기일 수 있다.A is a C ₁ -C ₂₀ alkylene group, -CH ₂ -included in the alkylene group may be substituted with -O- or -S-, and the alkylene group of A is a C ₁ -C ₁₀ alkyl group And

It may be further substituted with any one or two or more substituents selected from, and R ₃ may be a direct bond or a C ₁ -C ₅ alkylene group.

In terms of improving color purity and electrical stability, preferably Ar ₁ , Ar ₂ , Ar ₃ and Ar ₄ are each independently C ₆ -C ₂₀ aryl group,

에서 선택되는 어느 하나 또는 둘 이상의 치환기로 더 치환될 수 있으며, 상기 R₃은 C₁-C₅인 알킬렌기일 수 있다.The R ₁ and R ₂ are hydrogen, A is a C ₁ -C ₁₀ alkylene group, -CH ₂ -included in the alkylene group may be substituted with -O- or -S-, The alkylene group is a C ₁ -C ₅ alkyl group and

It may be further substituted with any one or two or more substituents selected from, and R ₃ may be a C ₁ -C ₅ alkylene group.

In terms of improving color purity and electrical stability, more preferably the Ar ₁ , Ar ₂ , Ar ₃ and Ar ₄ are each independently a C ₆ -C ₂₀ aryl group,

The R ₁ and R ₂ are hydrogen, and A may be a C ₁ -C ₅ alkylene group, and the alkylene group of A may be further substituted with a C ₁ -C ₃ alkyl group.

According to an aspect of the present invention, a diarylamine group is substituted at the 2nd substitution position of the carbazole group as described above. When a substituent is not included in the diarylamine group, luminous efficiency such as current efficiency can be remarkably improved, and color purity and electrical stability can be further improved.

According to an aspect of the present invention, in terms of interfacial properties with an electrode due to improved solubility and heat resistance in an organic solvent, the Ar ₁ , Ar ₂ , Ar ₃ and Ar ₄ of the organic light emitting compound represented by Formula 1 are each independently with a C ₁ -C ₁₀ alkyl groups and C ₁ -C ₁₀ alkoxy group in which one or more of the substituted C ₆ -C ₂₀ aryl group, two or more substituents selected from,

The R ₁ and R ₂ are each independently selected from hydrogen, a C ₁ -C ₅ alkyl group and a C ₁ -C ₅ alkoxy group,

에서 선택되는 어느 하나 또는 둘 이상의 치환기로 더 치환될 수 있으며, 상기 Ar₅ 및 Ar₆은 각각 독립적으로 C₆-C₂₀인 아릴기이고, 상기 C₆-C₂₀인 아릴기는 C₁-C₁₀인 알킬기 및 C₁-C₁₀인 알콕시기에서 선택되는 어느 하나 또는 둘 이상의 치환기로 더 치환될 수 있으며, 상기 R₃은 직접결합 또는 C₁-C₅인 알킬렌기일 수 있다.A is a C ₁ -C ₂₀ alkylene group, -CH ₂ -included in the alkylene group may be substituted with -O- or -S-, and the alkylene group of A is a C ₁ -C ₁₀ alkyl group And

It may be further substituted with any one or two or more substituents selected from, wherein Ar ₅ and Ar ₆ are each independently a C ₆ -C ₂₀ aryl group, and the C ₆ -C ₂₀ aryl group C ₁ -C ₁₀ It may be further substituted with any one or two or more substituents selected from a phosphorus alkyl group and a C ₁ -C ₁₀ alkoxy group, and R ₃ may be a direct bond or a C ₁ -C ₅ alkylene group.

In terms of the interface properties with the electrode due to improved solubility and heat resistance in organic solvents, the Ar ₁ , Ar ₂ , Ar ₃ and Ar ₄ of the organic light-emitting compound represented by Formula 1 are each independently C ₁ -C _{It is} a C ₆ -C ₂₀ aryl group further substituted with any one or two or more substituents selected from a ₅ phosphorus alkyl group and a C ₁ -C ₅ alkoxy group,

The R ₁ and R ₂ are each independently selected from hydrogen, a C ₁ -C ₃ alkyl group and a C ₁ -C ₃ alkoxy group,

에서 선택되는 어느 하나 또는 둘 이상의 치환기로 더 치환될 수 있으며, 상기 Ar₅ 및 Ar₆은 각각 독립적으로 C₆-C₂₀인 아릴기이고, 상기 C₆-C₂₀인 아릴기는 C₁-C₅인 알킬기 및 C₁-C₅인 알콕시기에서 선택되는 어느 하나 또는 둘 이상의 치환기로 더 치환될 수 있으며, 상기 R₃은 직접결합 또는 C₁-C₅인 알킬렌기일 수 있다.A is a C ₁ -C ₁₀ alkylene group, -CH ₂ -included in the alkylene group may be substituted with -O- or -S-, and the alkylene group of A is a C ₁ -C ₅ alkyl group And

It may be further substituted with any one or two or more substituents selected from, wherein Ar ₅ and Ar ₆ are each independently a C ₆ -C ₂₀ aryl group, and the C ₆ -C ₂₀ aryl group C ₁ -C ₅ It may be further substituted with any one or two or more substituents selected from a phosphorus alkyl group and a C ₁ -C ₅ phosphorus alkoxy group, and R ₃ may be a direct bond or a C ₁ -C ₅ alkylene group.

In terms of interfacial properties with the electrode due to improved solubility and heat resistance in organic solvents, more preferably, Ar ₁ , Ar ₂ , Ar ₃ and Ar ₄ of the organic light-emitting compound represented by Formula 1 are each independently C _1- A C ₆ -C ₂₀ aryl group further substituted with any one or two or more substituents selected from a C ₃ alkyl group and a C ₁ -C ₃ alkoxy group,

The R ₁ and R ₂ are each independently selected from hydrogen, a C ₁ -C ₃ alkyl group and a C ₁ -C ₃ alkoxy group, and A may be a C ₁ -C ₅ alkylene group.

According to an aspect of the present invention, the organic light-emitting compound is substituted with a diarylamine group at the 2nd substitution position of the carbazole group as described above. When a substituent is included in the diarylamine group, not only can the luminous efficiency such as current efficiency be significantly improved, but also the interfacial properties with the electrode can be further improved through improved solubility and heat resistance in an organic solvent.

At this time, other than the diarylamine groups, even if the 2-position to the substitution position which groups diarylamine selected from any one or a mixture of two or more selected from a C ₁ -C ₅ alkyl group and C ₁ -C ₅ alkoxy group other When the functional group is substituted, the driving voltage increases, the power consumption increases, and the luminous efficiency decreases, so that the object of the present invention cannot be achieved.

에서 선택되는 어느 하나 또는 둘 이상의 치환기로 더 치환되어도 턴-온 전압 및 구동전압을 현저히 감소시켜 전류효율을 현저히 향상시킬 수 있다.In addition, according to an aspect of the present invention, the alkylene group of A in Formula 1 is a C ₁ -C ₁₀ alkyl group and

Even if it is further substituted with any one or two or more substituents selected from, the turn-on voltage and the driving voltage can be significantly reduced, thereby remarkably improving the current efficiency.

According to an aspect of the present invention, the organic light-emitting compound may be used in an organic material layer of an organic light-emitting device due to its structural specificity, and more specifically, may be used as a host compound in the light-emitting layer in the organic material layer.

By providing an organic light-emitting device containing the organic light-emitting compound as described above, not only prevents crystallization during device fabrication by improving electron transfer efficiency, but also has good layer formation and can be driven by a low voltage, significantly reducing power consumption. Can be reduced. In addition, it can have excellent current efficiency, and can significantly improve light-emitting characteristics and device life.

The organic light-emitting compound according to the present invention is not substituted with a diarylamine group at the 2nd substitution position of the carbazole group, or the main chain of the linking group is composed of not an alkylene group, such as an arylene group containing an aromatic, or either If not satisfied, the object of the present invention cannot be achieved.

According to an aspect of the present invention, the organic light-emitting compound may be more specifically, a compound represented by the following structural formula, but is not limited thereto.

[constitutional formula]

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In this case, Me in the above structural formula means -CH ₃ .

The present invention provides an organic light-emitting device comprising the organic light-emitting compound represented by Formula 1 above.

In addition, by providing an organic light-emitting device including the organic light-emitting compound represented by Formula 1 described above, electrical stability and lifespan characteristics are improved, and high luminance light emission is possible, and excellent luminous efficiency and color purity may be exhibited.

According to an aspect of the present invention, the organic light emitting device includes a first electrode, a second electrode, and one or two or more organic material layers interposed between the first electrode and the second electrode, wherein the organic material layer has one light emitting layer. It may have a single-layer structure made of layers, but may have a multilayer structure of two or more layers including a light emitting layer. When the organic material layer of the organic light emitting device has a multilayer structure, it may be a structure in which, for example, a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and the like are stacked. However, the structure of the organic light-emitting device is not limited thereto, and may include a smaller number of organic material layers.

According to an aspect of the present invention, the organic material layer may include a light emitting layer including the organic light emitting compound of Formula 1, and the organic light emitting compound of Formula 1 may be included as a phosphorescent host in the light emitting layer. When the organic light-emitting compound of Formula 1 is included as a host material in the light-emitting layer, the light-emitting layer may include one or two or more dopants.

According to an aspect of the present invention, the first electrode may be an anode layer, and is an electrode for injecting holes into the hole injection layer. Therefore, the material for forming the anode layer is not limited as long as the properties are imparted to the anode layer. Specific examples of the material for forming the anode layer, any one or two or more metals selected from vanadium, chromium, copper, zinc, gold, and alloys thereof; Any one or two or more metal oxides selected from zinc oxide, indium oxide, indium tin oxide (ITO), indium zinc oxide (IZO), and the like; Any one or a combination of two or more metals and oxides selected from ZnO:Al and SnO ₂ :Sb; Any one or two or more conductive polymers selected from poly(3-methylthiophene), poly[3,4-(ethylene-1,2-dioxy)thiophene] (PEDT), polypyrrole and polyaniline; And the like, but are not limited to these. In addition, the anode layer may be formed of only one type of the above-described materials or may be formed of a mixture of a plurality of materials, and a multi-layered structure composed of a plurality of layers having the same composition or different composition may be formed.

According to an aspect of the present invention, the organic material layer necessarily includes a light emitting layer, and in a hole injection layer (HIL), a hole blocking layer (HBL), a hole transport layer (HTL), an electron transport layer (ETL), an electron injection layer (EIL), etc. Any one or more selected layers may be further included, and may be omitted if necessary.

According to an aspect of the present invention, the hole injection layer HIL may be formed on the first electrode by using various methods such as a vacuum deposition method, a spin coating method, a cast method, or a LB (Langmuir-Blodgett) method. . Materials for the hole injection layer that can be used include CuPc (copper phthalocyanine), NPD (N,N'-dinaphthyl-N,N'-phenyl-(1,1'-biphenyl)-4,4'-diamine), m -MTDATA (4,4',4"-tris(3-Methylphenylphenylamino)triphenylamine), 1-TNATA (4,4',4''-tris[1-naphthyl(phenyl)amino] triphenyl amine), 2-TNATA (4,4',4''-tris[2-naphthyl(phenyl)amino] triphenyl amine) and p-DPA-TDAB (1,3,5-tris[N-(4-diphenylaminophenyl)phenylamino] benzene), etc. Any one or two or more selected from the same aromatic amines, poly(3,4-ethylenedioxythiophene)-poly(styrnesulfonate)(PEDOT:PSS), which is a polythiophene derivative as a conductive polymer, may be used, etc. Preferably PEDOT:PSS is used. It may be used as a hole injection layer, and the hole injection layer may be coated on the top of the first electrode to a thickness of 10 to 60 nm.

In addition, according to an aspect of the present invention, the hole transport layer (HTL) is deposited on the hole injection layer so as to stably supply the holes introduced through the hole injection layer to the light emitting layer. As a material for the hole transport layer that can be used, a material that is commonly used can be used, and preferably NPB (N,N'-bis(naphthalen-1-yl)-N,N'-bis(phenyl)-benzidine) , NPD (N,N′-bis(naphthalen-1-yl)-N,N′-bis(phenyl)-2,2′-dimethylbenzidine), TPD (N,N′-Bis(3-methylphenyl)-N ,N′-diphenylbenzidine), TTB (N,N,N',N'-tetrakis(4-methylphenyl)-(1,1'-biphenyl)-4,4-diamine), TTP (N1,N4-diphenyl- N1,N4-dim-tolylbenzene-1,4-diamine), ETPD (N,N'-bis(4-methylphenyl)-N,N'-bis(4-ethylphenyl)-[1,1'-(3, 3'-dimethyl)biphenyl]-4,4'-diamine), VNPB (N4,N4′-di(naphthalen-1-yl)-N4,N4′-bis(4-vinylphenyl)biphenyl-4,4′- diamine), ONPB (N4,N4′-bis(4-(6-((3-ethyloxetan-3-yl)methoxy)hexyl)phenyl)-N4,N4′-diphenylbiphenyl-4,4′-diamine) and OTPD (N4,N4′-bis(4-(6-((3-ethyloxetan-3-yl)methoxy)hexyl)phenyl)-N4,N4′-diphenylbiphenyl-4,4′-diamine) or any one selected from Two or more low-molecular hole transport materials; Any one or two or more polymer hole transport materials selected from PVK (poly-N-vinylcarbazole), polyaniline, and (phenylmenyl) polysilane may be used. Preferably, NPB, NPD or VNPB may be used, and in the embodiment of the present invention, VNPB was used as the hole transport layer, and the hole transport layer may be stacked on top of the light emitting layer with a thickness of 10 to 60 nm.

According to an aspect of the present invention, the emission layer may be a phosphorescent emission layer, and by including the organic emission compound represented by Chemical Formula 1 according to the present invention, an organic light emitting device having high luminance and long life characteristics can be implemented. In the light-emitting layer of the organic light-emitting device according to the present invention, the film thickness of the light-emitting layer is not limited, but from the viewpoint of uniformity of the film or application of unnecessary high voltage during light emission, and improving the stability of the light-emitting color against a driving current, It is preferably adjusted in the range of 2 nm to 5 μm, more preferably in the range of 5 to 100 nm, and particularly preferably in the range of 10 to 50 nm.

In addition, according to an aspect of the present invention, the light emitting layer may obtain a color of high luminance with higher efficiency by using a phosphorescent dopant together. In this case, the used dopant is not limited, and a known dopant may be selected and used as necessary. The phosphorescent dopant is a compound capable of emitting light from triplet excitons, and is not particularly limited as long as it emits light from triplet excitons, and Ir, Pt, Os, Ti, Zr, Hf, Eu, Tb, Tm, Fe, Co, Ni, It is preferable that it is a metal complex containing any one or two or more metals selected from Ru, Rh, Re, Pd and P. A specific example is as described above in the composition for a light emitting layer.

In this case, a hole blocking layer (HBL) may be formed to prevent diffusion of triplet excitons or holes into the electron transport layer. In the case of forming the hole blocking layer by vacuum evaporation and spin coating, the conditions vary depending on the compound to be used, but may generally be within the same range of conditions as the hole injection layer. A known hole-blocking material can also be used, and examples thereof include an oxadiazole derivative, a triazole derivative, and a phenanthroline derivative. For example, the following BCP or the like can be used as a material for the hole blocking layer.

According to an aspect of the present invention, the electron transport layer (ETL) is mainly composed of a material containing a chemical component that attracts electrons. For this purpose, high electron mobility is required, and electrons are stably transferred to the light emitting layer through smooth electron transport. Supply. As a material for the electron transport layer that can be used according to the present invention, a commonly used material may be used, preferably TSPO1 (diphenyl-4-triphenylsilylphenylphosphine oxide), TPBi (1,3,5-tris(N-phenylbenzimiazole- 2-yl)benzene); Alq3 (Tris(8-hydroxyquinolinato)aluminum); BCP (2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline); PBD (2-(4-biphenyl)-5-(4-tert-butyl)-1,3,4-oxadizole), TAZ (3-(4-biphenyl)-4-phenyl-5-(4-tert- butyl)-1,2,4-triazole), OXD-7 (1,3-bis[2-(4-tert-butylphenyl)-1,3,4-oxadiazo-5-yl]benzene), etc. ; phenylquinozaline; TmPyPB (3,3'-[5'-[3-(3-Pyridinyl)phenyl] [1,1':3',1''-terphenyl]-3,3''-diyl] bispyridine) Any one or two or more may be used, but is not limited thereto. Preferably, TSPO1, TPBi or Alq3 may be used, and TPBi was used as the electron transport layer in the embodiment of the present invention, and the electron transport layer may be stacked on top of the light emitting layer with a thickness of 5 to 150 nm.

In addition, according to an aspect of the present invention, the electron injection layer may be deposited to a thickness of 1 to 50 nm using LIF or Liq (lithium quinolate), but is not limited thereto.

In addition, according to an aspect of the present invention, the second electrode may be a negative electrode layer, and any one selected from magnesium, calcium, sodium, potassium, titanium, indium, yttrium, lithium, gadolinium, aluminum, silver, tin, and lead Alternatively, any one or two or more selected from metals having a low work function, such as two or more metals, alloys thereof, and a multilayered material such as LiF/Al or LiO ₂ /Al, may be used, and preferably Al .

The organic light-emitting device according to the present invention exhibits an efficient host-dopant energy transfer mechanism, and thus can exhibit a reliable high-efficiency light-emitting characteristic based on an effect of improving the electron density distribution. In addition, it is possible to overcome a decrease in initial efficiency and low lifespan characteristics of existing materials, and secure high-performance light emitting characteristics having high efficiency and long life in each color.

The organic light emitting device according to the present invention described above may be applied to a display device, and the display device may be a display device using a backlight unit, and the organic light emitting device may be used as a light source and a single light source of a backlight unit. The display device may be an organic electroluminescent display (OLED), but is not limited thereto.

Hereinafter, a composition for an organic light-emitting device light-emitting layer, a novel organic light-emitting compound, and an organic light-emitting device including the same according to the present invention will be described in more detail through the following examples. However, the following examples are only one reference for describing the present invention in detail, and the present invention is not limited thereto, and may be implemented in various forms.

Further, unless otherwise defined, all technical and scientific terms have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. The terms used in the description herein are merely to effectively describe specific embodiments and are not intended to limit the invention.

In addition, the unit of the additive not specifically described in the specification may be a weight %.

[Method of measuring properties]

Electrical characteristics of the fabricated OLED device were specified with a Keithley 2400 source measurement unit, and luminance, emission spectrum, current efficiency, and external quantum efficiency were measured with a Konica-Minolta CS-2000 spectroradiometer. All measurements were performed in a normal atmosphere at room temperature and pressure.

[Synthesis Example 1] Synthesis of dimeric bromocarbazole intermediate

To a solution of 2-bromocarbazole (4.92 g, 20 mmol) in toluene (20 mL), 50% aqueous sodium hydroxide solution (20 mL) and tetrabutylammonium bromide (n=0.32 g, 1 mmol) were added and stirred. . After 5 minutes, dibromoalkane (10 mol) was added dropwise and heated to reflux for 3 hours. After lowering the temperature, water (100 mL) was added to terminate the reaction, and the organic layer was extracted with ethyl acetate (50 mL). The separated organic vapor was washed several times with water, dried over MgSO ₄ and concentrated in vacuo. The resulting white crystals were used directly in the next reaction.

[Production Example 1] Compound MA2-1

In Synthesis Example 1, dibromoalkane was synthesized using dibromopropane.

¹ H NMR (400 MHz, CDCl ₃ , ppm): δ = 8.08 (d, 2H), 7.96 (d, 2H), 7.46-7.42 (m, 2H), 7.37-7.35 (m, 4H), 7.29-7.25 (m, 2H), 7.17 (d, 2H), 4.29 (t, 4H), 2.52-2.44 (m, 2H).

[Production Example 2] Compound MA2-20

In Synthesis Example 1, dibromoalkane was synthesized using dibromobutane.

¹ H NMR (400 MHz, CDCl ₃ , ppm): δ = 8.07 (d, 2H), 7.95 (d, 2H), 7.49-7.46 (m, 4H), 7.36 (d, 2H), 7.28-7.25 (m , 4H), 4.22 (t, 4H), 1.98 (t, 4H).

[Production Example 3] Compound MA2-21

In Synthesis Example 1, dibromoalkane was synthesized using dibromohexane.

¹ H NMR (400 MHz, CDCl ₃ , ppm): δ = 8.07 (d, 2H), 7.95 (d, 2H), 7.52 (d, 2H), 7.49-7.45 (m, 2H), 7.35-7.34 (m , 2H), 7.33-7.32 (m, 2H), 7.25 (t, 2H), 4.22 (t, 4H), 1.88-1.80 (m, 2H), 1.44-1.36 (m, 2H).

[Comparative Preparation Example 1]

[Formula 2]

In Synthesis Example 1, 4-bromocarbazole was used instead of 2-bromocarbazole, and dibromoalkane was used as dibromopropane.

¹ H NMR (400 MHz, CDCl ₃ , ppm): δ = 8.80 (d, 2H), 7.55-7.51 (m, 2H), 7.42 (d, 2H), 7.40-7.35 (m, 4H), 7.33-7.27 (m, 2H), 4.35 (t, 4H), 2.52-2.40 (m, 2H).

[Comparative Preparation Example 2]

[Formula 3]

In Synthesis Example 1, it was synthesized using α,α′-dibromo-p-xylene instead of dibromoalkane.

¹ H NMR (400 MHz, CDCl ₃ , ppm): δ = 8.08 (d, 2H), 7.96 (d, 2H), 7.50 (d, 2H), 7.45-7.42 (m, 2H), 7.29-7.23 (m) , 6H), 7.12-7.10 (m, 4H), 5.45 (s, 4H).

[Synthesis Example 2] Synthesis of dimeric 2-diarylaminocarbazole compound

Dimeric 2-bromocarbazole intermediate (1 mmol), diarylamine (2 mmol), Pd ₂ dba ₃ (5 mol%), (t-Bu) ₃ P (20 mol%), t-BuONa ( 3 mmol) was stirred with toluene (15 ml) in a nitrogen atmosphere and heated to reflux for 5 hours. The reaction was filtered through Celite while hot, and the filtrate was concentrated in vacuo. In addition, a final product was obtained by separating and purifying through silica gel column chromatography with a developing solution of [normal hexane: ethyl acetate = 10: 1 volume ratio].

[Example 1] Synthesis of MA2-2

[Formula 4]

In Synthesis Example 2, MA2-1 prepared in Preparation Example 1 and diarylamine were synthesized as diphenylamine.

¹ H NMR (400 MHz, CDCl ₃ , ppm): δ = 8.02 (d, 2H), 7.97 (d, 2H), 7.31 (d, 2H), 7.24-7.19 (m, 10H), 7.14-7.12 (d , 8H), 7.03-6.99 (m, 8H), 6.95 (d, 2H), 4.11 (t, 4H), 2.26-2.21 (m, 2H).

[Example 2] Synthesis of MA2-23

[Formula 5]

In Synthesis Example 2, MA2-20 prepared in Preparation Example 2 and diarylamine were synthesized as diphenylamine.

¹ H NMR (400 MHz, CDCl ₃ , ppm): δ = 8.02 (d, 2H), 7.95 (d, 2H), 7.37 (t, 2H), 7.32-7.27 (m, 6H), 7.24-7.15 (m , 10H), 7.12-7.1 (m, 6H), 7.00-6.96 (m, 6H), 4.11 (t, 4H), 2.26-2.21 (m, 2H).

[Example 3] Synthesis of MA2-24

[Formula 6]

In Synthesis Example 2, MA2-21 prepared in Preparation Example 3 and diarylamine were synthesized using diphenylamine.

¹ H NMR (400 MHz, CDCl ₃ , ppm): δ = 8.03 (d, 2H), 7.97 (d, 2H), 7.40 (t, 2H), 7.28 (d, 2H), 7.24-7.20 (m, 10H) ), 7.17-7.13 (m, 8H), 7.09 (d, 2H), 7.02-6.95 (m, 6), 4.09 (t, 4H), 1.73-1.64 (m, 4H), 1.26-1.19 (m, 4H) ).

[Example 4] Synthesis of MA2-16

[Formula 7]

In Synthesis Example 2, MA2-1 prepared in Preparation Example 1 and diarylamine were synthesized using 4-methoxydiphenylamine.

¹ H NMR (400 MHz, CDCl ₃ , ppm): δ = 7.99 (d, 2H), 7.93 (d, 2H), 7.30-7.27 (m, 4H), 7.21-7.16 (m, 6H), 7.09-7.05 (m, 8H), 6.96-6.92 (m, 8H), 6.79 (d, 4), 4.10 (t, 4H), 3.78 (s, 6H), 2.27-2.20 (m, 2H).

[Example 5] Synthesis of MA2-17

[Formula 8]

In Synthesis Example 2, MA2-1 prepared in Preparation Example 1 and diarylamine were synthesized using 4,4'-dimethoxydiphenylamine.

¹ H NMR (400 MHz, CDCl ₃ , ppm): δ = 7.97 (d, 2H), 7.88 (d, 2H), 7.28 (t, 2H), 7.18 (t, 2H), 7.05 (d, 8H), 6.95 (d, 2H), 6.86 (dd, 2), 6.85 (dd, 2H), 6.78 (d, 8H), 4.09 (t, 4H), 3.78 (s, 6H), 2.24-2.17 (m, 2H) .

[Example 6] Synthesis of MA2-30

[Formula 9]

In Synthesis Example 2, MA2-1 prepared in Preparation Example 1 and diarylamine were synthesized using N-phenyl-1-naphthylamine.

¹ H NMR (400 MHz, CDCl ₃ , ppm): δ = 8.02 (d, 2H), 7.97 (d, 2H), 7.31 (d, 2H), 7.24-7.19 (m, 10H), 7.14-7.12 (d , 8H), 7.03-6.99 (m, 8H), 6.95 (d, 2H), 4.11 (t, 4H), 2.26-2.21 (m, 2H).

[Example 7] Synthesis of MA2-40

[Formula 10]

In Synthesis Example 2, the dimeric 2-bromocarbazole intermediate was used as 1,3-bis(2-bromo-7-methoxy-9H-carbazol-9-yl)propane, and the diarylamine was used as diphenylamine. Was synthesized using.

¹ H NMR (400 MHz, CDCl ₃ , ppm): δ = 8.00 (d, 2H), 7.96 (d, 2H), 7.22-7.17 (m, 8H), 7.11-7.09 (d, 8H), 7.03-6.99 (m, 10H), 6.95 (d, 2H), 4.10 (t, 4H), 3.91 (s, 6H), 2.26-2.20 (m, 2H).

[Example 8] Synthesis of MA2-50

[Formula 11]

In Synthesis Example 1, 2-diphenylaminocarbazole (44 mmol) was used in place of 2-bromocarbazole, and 1,3-dibromo-2,2-bis(bromomethyl) was used in place of dibromoalkane. It was synthesized by reacting for 12 hours using propane (10 mmol).

¹ H NMR (400 MHz, CDCl ₃ , ppm): δ = 8.02 (d, 4H), 7.95 (d, 4H), 7.32 (d, 4H), 7.25-7.17 (m, 20H), 7.15-7.10 (d) , 16H), 7.03-6.97 (m, 16H), 6.97 (d, 4H), 4.12 (t, 8H), 2.28-2.19 (m, 4H).

[Comparative Example 1] Synthesis of MA2-6

[Formula 12]

In Synthesis Example 2, 1,3-bis(4-bromo-9H-carbazol-9-yl)propane and diphenylamine were used.

¹ H NMR (400 MHz, CDCl ₃ , ppm): δ = 7.77 (d, 2H), 7.40 (t, 2H), 7.32 (t, 2H), 7.23-7.17 (m, 9H), 7.16-7.10 (m , 11H), 7.01-6.93 (m, 8H), 4.43 (t, 4H), 2.61-2.54 (m, 2H).

[Comparative Example 2]

[Formula 13]

In Synthesis Example 2, 1,4-bis((2-bromo-9H-carbazol-9-yl)methyl)benzene and diphenylamine of Comparative Preparation Example 1 were used.

¹ H NMR (400 MHz, CDCl ₃ , ppm): δ = 8.03 (d, 2H), 7.96 (d, 2H), 7.32 (d, 2H), 7.27-7.20 (m, 14H), 7.15-7.10 (d) , 8H), 7.03-6.97 (m, 8H), 6.96 (d, 2H), 5.33 (s, 4H).

[Example 9]

ITO (indium tin oxide, 10 Ω per square) coated glass was used as the substrate, and after cleaning, it was treated with UV ozone for 10 minutes before device fabrication, and the hole injection layer (HIL) was prepared with a PEDOT:PSS solution (Clevios AI 4083). After spin coating to a thickness of 30 nm at 2,500 rpm for 40 seconds, it was dried in vacuum at 150° C. for 30 minutes. The light emitting layer (EML) on the hole injection layer is a solution obtained by dissolving the compound (MA2-2) prepared in Example 1: Ir(mppy) ₃ =93:7 in 1,2-dichloroethane at 0.64% by weight at 1,800 rpm. After spin-coating to a thickness of 40 nm for 40 seconds, the remaining solvent was removed at 60° C. for 30 minutes. Thereafter, an electron transport layer (ETL) is placed on the light emitting layer with TPBi(2,2',2"-(1,3,5-Benzinetriyl)-tris(1-phenyl-1-H-benzimidazole). )) was formed to be 50 nm by vacuum thermal evaporation at 0.5Å/s. LiF was 0.1Å/s on the electron transport material layer to a thickness of 1 nm, and aluminum (Al) was 5.0 Å/s. It was formed by vacuum thermal evaporation to a thickness of 100 nm, and the coating and drying of the hole injection layer and the light emitting layer were carried out in an inert atmosphere in a nitrogen-filled glove box. It was sealed through a glass cover.

[Example 10]

In Example 9, the same procedure was performed except that the compound prepared in Example 2 was used instead of the compound prepared in Example 1 (MA2-2) as the host material.

[Example 11]

In Example 9, the same procedure was carried out except that the compound prepared in Example 3 was used instead of the compound prepared in Example 1 (MA2-2) as the host material.

[Example 12]

In Example 9, the same procedure was carried out except that the compound prepared in Example 4 was used instead of the compound prepared in Example 1 (MA2-2) as the host material.

[Example 13]

In Example 9, the same procedure was carried out except that the compound prepared in Example 5 was used instead of the compound prepared in Example 1 (MA2-2) as the host material.

[Example 14]

In Example 9, the same procedure was performed except that the compound prepared in Example 6 was used instead of the compound prepared in Example 1 (MA2-2) as the host material.

[Example 15]

In Example 9, the same procedure was carried out except that the compound prepared in Example 7 was used instead of the compound prepared in Example 1 (MA2-2) as the host material.

[Example 16]

In Example 9, the same procedure was carried out except that the compound prepared in Example 8 was used instead of the compound prepared in Example 1 (MA2-2) as the host material.

[Comparative Example 3]

In Example 9, except that the compound (MA2-6) prepared in Comparative Example 1 was used instead of the compound (MA2-2) prepared in Example 1 as the host material, the same procedure was carried out.

[Comparative Example 4]

26DCzPPy (Sigma-Aldrich, 2,6-bis(3-(9H-Carbazol-9-yl) represented by the following Formula 14 in place of the compound (MA2-2) prepared in Example 1, which is the host material in Example 9) ) Except for using phenyl) pyridine) was carried out in the same manner.

[Formula 14]

[Comparative Example 5]

PVK (Sigma-Aldrich, number average molecular weight 25,000 to 50,000 g/mol, Poly(9-vinylcarbazole) represented by the following formula 15 in place of the compound (MA2-2) prepared in Example 1, which is the host material in Example 9 ) Was carried out in the same manner except for using.

[Formula 15]

[Comparative Example 6]

In Example 9, except that the compound prepared by Comparative Example 2 was used in place of the compound (MA2-2) prepared by Example 1, which is the host material, the same procedure was carried out.

A light emission test was conducted by applying a voltage of 0 to 15 V to the organic light emitting devices prepared in Examples 9 to 16 and Comparative Examples 3 to 6, and the electroluminescence characteristics and basic physical properties measurement results are shown in Table 1 below.

At 1 nit At 1,000 nit L _max
[cd/m ² ] EQE _max
[%] Current Efficiency [cd/A] V _turn-on
[V] V _driving
[V] EQE
[%] Max. At 1,000 nit Example 9 3.01 5.38 14.73 43,437 16.02 55.49 51.15 Example 10 3.05 5.40 14.51 43,124 15.99 55.23 51.02 Example 11 3.07 5.44 14.01 42,876 15.99 55.02 50.79 Example 12 2.99 5.31 13.89 42,022 15.86 54.77 50.01 Example 13 2.95 5.25 13.98 42,101 15.90 54.80 50.45 Example 14 3.10 5.42 14.11 43,033 15.91 55.13 50.99 Example 15 3.20 5.50 13.92 43,225 15.95 55.22 51.02 Example 16 3.11 5.40 14.22 43,357 15.99 55.31 51.11 Comparative Example 3 4.38 7.07 7.96 14,574 9.87 34.25 27.66 Comparative Example 4 4.50 8.22 4.53 14,069 5.27 18.41 15.79 Comparative Example 5 4.17 8.20 7.20 15,164 12.15 42.90 25.28 Comparative Example 6 3.55 6.11 11.87 39,121 13.97 48.37 30.54

As shown in Table 1 above, it was confirmed that the organic light-emitting device including the organic light-emitting compound according to the present invention as a light-emitting layer host material exhibited excellent device characteristics compared to conventional materials such as Comparative Examples 4 and 5. Specifically, as shown in FIGS. 1 and 2, the organic light emitting device including the organic light emitting compound according to the present invention in the light emitting layer can significantly lower the _turn-on voltage (V _turn-on ) and the driving voltage (V _driving ). Confirmed. In addition, it was confirmed that not only has excellent luminescence characteristics with excellent luminance (L _max ), current efficiency, and external quantum efficiency (EQE), but also power consumption can be remarkably improved by enhancing the driving voltage.

In addition, it was confirmed that, as in Examples 9 to 11 and 14, when the diarylamine group does not contain a substituent, the color purity and electrical stability are more excellent compared to Examples 12, 13 and 15 in which the substituent is present. When a substituent is included in the diarylamine group or carbazole group as in Examples 12, 13 and 15, the turn-on and driving voltage can be further lowered compared to Examples 9 to 11 and 14, and improved solubility in organic solvents And it was confirmed that the interfacial properties with the electrode were more excellent due to heat resistance.

In addition, when the Example of the present invention is compared with Comparative Example 3, as in Comparative Example 3, when a diarylamine group is substituted at a position other than the 2nd substitution position of the carbazole group, a higher turn-on It was confirmed that it not only had a voltage and a driving voltage, but also had remarkably low luminance, current efficiency, and external quantum efficiency.

In addition, when the examples of the present invention are compared with Comparative Examples 4 and 6, as in Comparative Examples 3 and 6, when an arylene group is present in the connector, not only has a high turn-on voltage and a driving voltage, but also a remarkably low luminance and current. It was confirmed that it has efficiency and external quantum efficiency.

(이 때, R₁은 직접결합 또는 C₁-C₃인 알킬렌기이다.)에서 선택되는 어느 하나 또는 둘 이상의 치환기로 더 치환되어도 턴-온 전압 및 구동전압을 현저히 감소시킬 수 있고, 전류효율을 현저히 향상시킬 수 있음을 확인하였다.In addition, through Example 14, the alkylene group of A in Formula 1 is a C ₁ -C ₅ alkyl group and

(At this time, R ₁ is a direct bond or a C ₁ -C ₃ alkylene group.) Even if it is further substituted with one or two or more substituents selected from, the turn-on voltage and driving voltage can be significantly reduced, and current efficiency It was confirmed that it can be remarkably improved.

Accordingly, when the organic light-emitting compound having a characteristic structure according to the present invention is used as a host material for light emission in the light-emitting layer, the turn-on voltage and the driving voltage are further lowered, thereby reducing power consumption. Moreover, by effectively confining excitons in the emission layer, luminance, current efficiency, and quantum efficiency can be dramatically increased, and roll-off can be suppressed at a high current density, thereby enabling more excellent durability, thereby having long life characteristics.

As described above, in the present invention, a composition for an organic light-emitting device light-emitting layer, a novel organic light-emitting compound, and an organic light-emitting device including the same have been described through specific details and limited examples, but this is provided to help a more general understanding of the present invention However, the present invention is not limited to the above embodiments, and various modifications and variations are possible from these descriptions by those of ordinary skill in the field to which the present invention belongs.

Therefore, the spirit of the present invention is limited to the described embodiments and should not be defined, and all things that are equivalent or equivalent to the claims as well as the claims to be described later fall within the scope of the present invention. .

Claims (12)

Including a dopant and a host,
The host is an organic light emitting compound represented by the following formula (1) composition for an organic light emitting device emission layer.
[Formula 1]

In Formula 1,
The Ar ₁ , Ar ₂ , Ar ₃ and Ar ₄ are each independently a C ₆ -C ₂₀ aryl group, and the C ₆ -C ₂₀ aryl group may be further substituted with a C ₁ -C ₁₀ alkoxy group,
R ₁ and R ₂ are each independently hydrogen or a C ₁ -C ₁₀ alkoxy group,
Wherein A is a C ₁ -C ₂₀ alkylene group, and the alkylene group of A is a C ₁ -C ₁₀ alkyl group and

It may be further substituted with any one or two or more substituents selected from, wherein Ar ₅ and Ar ₆ are each independently a C ₆ -C ₂₀ aryl group, and the C ₆ -C ₂₀ aryl group C ₁ -C ₁₀ It may be further substituted with a phosphorus alkoxy group, and R ₃ is a direct bond or a C ₁ -C ₅ alkylene group. The method of claim 1,
The organic light-emitting compound represented by Formula 1
Ar ₁ , Ar ₂ , Ar ₃ and Ar ₄ are each independently a C ₆ -C ₂₀ aryl group,
Wherein R ₁ and R ₂ are hydrogen,
Wherein A is a C ₁ -C ₂₀ alkylene group, and the alkylene group of A is a C ₁ -C ₁₀ alkyl group and

_May be further substituted with any one or two or more substituents selected from, wherein Ar ₅ and Ar ₆ are each independently a C ₆ -C ₂₀ aryl group, and R ₃ is a direct bond or a C ₁ -C ₅ alkyl A composition for a light emitting layer of an organic light-emitting device that is a ren group. The method of claim 1,
The organic light-emitting compound represented by Formula 1
Ar ₁ , Ar ₂ , Ar ₃ and Ar ₄ are each independently a C ₆ -C ₂₀ aryl group further substituted with a C ₁ -C ₁₀ alkoxy group,
The R ₁ and R ₂ are each independently selected from hydrogen, a C ₁ -C ₅ alkyl group and a C ₁ -C ₅ alkoxy group,
Wherein A is a C ₁ -C ₂₀ alkylene group, and the alkylene group of A is a C ₁ -C ₁₀ alkyl group and

It may be further substituted with any one or two or more substituents selected from, wherein Ar ₅ and Ar ₆ are each independently a C ₆ -C ₂₀ aryl group, and the C ₆ -C ₂₀ aryl group C ₁ -C ₁₀ It may be further substituted with a phosphorus alkoxy group, wherein R ₃ is a direct bond or a C ₁ -C ₅ alkylene group, an organic light emitting device composition for a light emitting layer. The method of claim 1,
The dopant is a metal complex containing one or two or more metals selected from Ir, Pt, Os, Ti, Zr, Hf, Eu, Tb, Tm, Fe, Co, Ni, Ru, Rh, Re, Pd and P Composition for an organic light emitting device emitting layer comprising a. The method of claim 1,
The composition for an organic light emitting device emitting layer comprising the host and the dopant in a weight ratio of 70:30 to 99:1. An organic light-emitting compound represented by the following formula (1).
[Formula 1]

In Formula 1,
The Ar ₁ , Ar ₂ , Ar ₃ and Ar ₄ are each independently a C ₆ -C ₂₀ aryl group, and the C ₆ -C ₂₀ aryl group may be further substituted with a C ₁ -C ₁₀ alkoxy group,
R ₁ and R ₂ are each independently hydrogen or a C ₁ -C ₁₀ alkoxy group,
Wherein A is a C ₁ -C ₂₀ alkylene group, and the alkylene group of A is a C ₁ -C ₁₀ alkyl group and

It may be further substituted with any one or two or more substituents selected from, and Ar ₅ and Ar ₆ are each independently a C ₆ -C ₂₀ aryl group, and the C ₆ -C ₂₀ aryl group is C ₁ -C ₁₀ It may be further substituted with an alkoxy group, and R ₃ is a direct bond or a C ₁ -C ₅ alkylene group. The method of claim 6,
The organic light-emitting compound represented by Formula 1
Ar ₁ , Ar ₂ , Ar ₃ and Ar ₄ are each independently a C ₆ -C ₂₀ aryl group,
Wherein R ₁ and R ₂ are hydrogen,
Wherein A is a C ₁ -C ₂₀ alkylene group, and the alkylene group of A is a C ₁ -C ₁₀ alkyl group and

_May be further substituted with any one or two or more substituents selected from, Ar ₅ and Ar ₆ are each independently a C ₆ -C ₂₀ aryl group, the C ₆ -C ₂₀ aryl group C ₁ -C ₁₀ The organic light-emitting compound may be further substituted with an alkoxy group, wherein R ₃ is a direct bond or a C ₁ -C ₅ alkylene group. delete The method of claim 6,
Formula 1 is an organic light-emitting compound represented by the following structural formula.
[constitutional formula]

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. An organic light-emitting device comprising the organic light-emitting compound according to any one of claims 6, 7 and 9. The method of claim 10,
The organic light-emitting device includes a first electrode, a second electrode, and one or two or more organic material layers interposed between the first electrode and the second electrode, and the organic material layer includes an emission layer containing the organic light-emitting compound. Light-emitting device. The method of claim 10,
The organic light emitting device is that the organic light emitting compound is included as a host of the light emitting layer.

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