JP2014072407A - Organic electroluminescent element material and organic electroluminescent element using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an organic EL element capable of obtaining long life phosphorescence and an organic EL element material for realizing the same.SOLUTION: The organic EL element material is a compound including an indolocarbazole skeleton and a nitrogen-containing complex ring group within the same molecule. The nitrogen-containing complex ring group has, as a substituent group, an electron attractive group and/or a substituent group X whose Hammet rule substituent constant ((σp (para)) takes on a positive value, an aromatic hydrocarbon group having 6-30 ring formation carbons replaced with the substituent group X, or a heterocyclic group (W) having 5-30 ring formation carbons replaced with the substituent group X. The organic EL element material is used preferably in a luminescent layer.

Description

  The present invention relates to a material for an organic electroluminescence element and an organic electroluminescence element using the same.

  When a voltage is applied to an organic electroluminescence element (hereinafter also referred to as an organic EL element), holes from the anode and electrons from the cathode are injected into the light emitting layer. Then, in the light emitting layer, the injected holes and electrons are recombined to form excitons. At this time, singlet excitons and triplet excitons are generated at a ratio of 25%: 75% according to the statistical rule of electron spin. When classified according to the light emission principle, the fluorescence type uses light emitted from singlet excitons, and therefore the internal quantum efficiency of the organic EL element is said to be limited to 25%. On the other hand, in the phosphorescent type, since light emission by triplet excitons is used, it is known that the internal quantum efficiency can be increased to 100% when intersystem crossing is efficiently performed from singlet excitons.

  Conventionally, in an organic EL element, an optimal element design has been made according to a light emission mechanism of a fluorescent type and a phosphorescent type. In particular, it is known that phosphorescent organic EL elements cannot obtain high-performance elements by simple diversion of fluorescent element technology because of their light emission characteristics. The reason is generally considered as follows.

First, since phosphorescence emission is emission using triplet excitons, the energy gap of the compound used in the light emitting layer must be large. This is because the value of the singlet energy of a compound (the energy difference between the lowest excited singlet state and the ground state) is usually the triplet energy of the compound (the energy between the lowest excited triplet state and the ground state). This is because it is larger than the value of the difference.
Therefore, in order to efficiently confine the triplet energy of the phosphorescent dopant material in the device, first, a host material having a triplet energy larger than the triplet energy of the phosphorescent dopant material must be used for the light emitting layer. I must. Further, when providing the electron transport layer and the hole transport layer adjacent to the light emitting layer, a compound having a triplet energy larger than that of the phosphorescent dopant material must be used for the electron transport layer and the hole transport layer. Thus, when based on the element design concept of the conventional organic EL element, it leads to using a compound having a larger energy gap for the phosphorescent organic EL element as compared with the compound used for the fluorescent organic EL element. The drive voltage of the whole organic EL element rises.

In addition, hydrocarbon compounds with high oxidation resistance and reduction resistance, which are useful in fluorescent elements, have a large energy gap due to a large spread of π electron clouds. Therefore, in a phosphorescent organic EL element, it is difficult to select such a hydrocarbon compound, and an organic compound containing a heteroatom such as oxygen or nitrogen is selected. As a result, the phosphorescent organic EL element is There is a problem that the lifetime is shorter than that of a fluorescent organic EL element.
Furthermore, the fact that the exciton relaxation rate of the triplet exciton of the phosphorescent dopant material is much longer than that of the singlet exciton also greatly affects the device performance. That is, since light emitted from singlet excitons has a high relaxation rate that leads to light emission, the diffusion of excitons to the peripheral layers of the light-emitting layer (for example, a hole transport layer or an electron transport layer) hardly occurs and is efficient. Light emission is expected. On the other hand, light emission from triplet excitons is spin-forbidden and has a slow relaxation rate, so that excitons are likely to diffuse to the peripheral layer, and thermal energy deactivation occurs from other than specific phosphorescent compounds. End up. That is, control of the recombination region of electrons and holes is more important than the fluorescent organic EL element.
For the reasons described above, in order to improve the performance of phosphorescent organic EL elements, material selection and element design different from those of fluorescent organic EL elements are required.
As such an organic EL material, an indolocarbazole derivative, which has been conventionally known as a main skeleton of a hole transporting material and exhibits high triplet energy, has been used as a useful phosphorescent host material.

Patent Document 1 describes that a compound containing an indolocarbazole skeleton and a nitrogen-containing heterocyclic group in the same molecule is used as a material for an organic EL device. This compound has a molecular design that balances charge transport by introducing an electron-deficient nitrogen-containing heterocyclic group into the hole-transporting indolocarbazole skeleton.
However, further improvement of the lifetime of the organic EL element is required, and development of a material for an organic EL element that can realize a longer lifetime is desired.

International Publication No. WO2008 / 056746

  An object of the present invention is to provide an organic EL element capable of obtaining long-lived phosphorescence and a material for an organic EL element that realizes the organic EL element.

［式（Ｉ）中、
Ａ^１、Ａ^２、Ｂ¹、Ｂ^２及びＣは、それぞれ独立に、単結合、置換もしくは無置換の環形成炭素数６〜３０の芳香族炭化水素基、又は置換もしくは無置換の環形成原子数５〜３０の複素環基を表す。
Ｙ^１〜Ｙ^１０は、それぞれ独立に、Ｎ（窒素原子）又はＣＲ^ａ（Ｃは炭素原子）を表す。但し、Ｙ^１〜Ｙ^１０のうち、隣接する２つがＣＲ^ａである場合、隣接するＣＲ^ａにおけるＲ^ａの一部同士が結合して環構造を形成していてもよい。
Ｒ^ａは、それぞれ独立に、水素原子、ハロゲン原子、シアノ基、置換もしくは無置換の炭素数１〜２０のアルキル基、置換もしくは無置換の炭素数１〜２０のアルコキシ基、置換もしくは無置換の炭素数１〜２０のハロアルキル基、置換もしくは無置換の炭素数１〜２０のハロアルコキシ基、置換もしくは無置換のシリル基、置換もしくは無置換の炭素数２〜２０のジアルキルアミノ基、置換もしくは無置換の炭素数１２〜３０のジアリールアミノ基、置換もしくは無置換の環形成炭素数６〜３０の芳香族炭化水素環基、置換もしくは無置換の環形成原子数５〜３０の複素環基を表し、複数のＲ^ａは、互いに同一でも異なっていてもよい。
ｓａ及びｔａは、それぞれ独立に、０〜５の整数を表し、ｓｂ及びｔｂは、それぞれ０〜４の整数を表し、ｕは０〜２の整数を表し、ｓａ＋ｓｂ＋ｔａ＋ｔｂ＋ｕは１〜５の整数である。
ｓａが１〜５の場合、Ａ^１と（Ｑ^１）_ｓａのＱ^１は結合している。ｓｂが１〜４の場合、Ｙ^１〜Ｙ^４の少なくとも１つと（Ｂ^１−Ｑ^１）_ｓｂのＢ^１は結合している。
ｔａが１〜５の場合、Ａ^２と（Ｑ^２）_ｔａのＱ^２は結合している。ｔｂが１〜４の場合、Ｙ^５〜Ｙ^８の少なくとも１つと（Ｂ^２−Ｑ^２）_ｔｂのＢ^２は結合している。
ｕが１〜２の場合Ｙ^９及びＹ^１０の少なくとも１つと（Ｃ−Ｑ^３）_ｕのＣは結合している。
Ｑ^１、Ｑ^２及びＱ^３は、それぞれ独立に、−Ａｚ−Ｗ_ｑを表す。
ｑは１〜４の整数を表す。
Ｑ^１が複数ある場合、複数のＱ^１は互いに同一でも異なっていてもよい。Ｑ^２が複数ある場合、複数のＱ^２は互いに同一でも異なっていてもよい。Ｑ^３が複数ある場合、複数のＱ^３は互いに同一でも異なっていてもよい。
上記Ａｚは下記式（Ｘ）で表される環の（ｑ＋１）価の基である。

（式（Ｘ）において、Ｚ^１〜Ｚ^５は、それぞれ独立に、窒素原子又はＣＲ^ｂを表す。
前記ＣＲ^ｂにおいて、Ｒ^ｂは、前記Ｒ^ａと同義である。但し、Ｚ^１〜Ｚ^５のうち、隣接する２つがＣＲ^ｂである場合、隣接するＣＲ^ｂにおけるＲ^ｂの一部同士が結合して環構造を形成していてもよい。
Ｒ^ｂが複数存在する場合、複数のＲ^ｂは互いに同一でも異なっていてもよい。）
Ａｚが複数ある場合、複数のＡｚは互いに同一でも異なっていてもよい。
Ｗは、置換基Ｘ、置換基Ｘで置換された環形成炭素数６〜３０の芳香族炭化水素基又は置換基Ｘで置換された環形成原子数５〜３０の複素環基を表す。ただし、置換基Ｘで置換された環形成炭素数６〜３０の芳香族炭化水素基及び置換基Ｘで置換された環形成原子数５〜３０の複素環基は、置換基Ｘ以外の置換基を有していてもよい。置換基Ｘは、電子吸引基である。Ｗが複数ある場合、複数のＷは互いに同一でも異なっていてもよい。］
２．下記式（１）〜（６）のいずれかで表される有機エレクトロルミネッセンス素子用材料。

［式（Ｉ）中、
Ａ^１、Ａ^２、Ｂ¹、Ｂ^２及びＣは、それぞれ独立に、単結合、置換もしくは無置換の環形成炭素数６〜３０の芳香族炭化水素基、又は置換もしくは無置換の環形成原子数５〜３０の複素環基を表す。
Ｙ^１〜Ｙ^１０は、それぞれ独立に、Ｎ（窒素原子）又はＣＲ^ａ（Ｃは炭素原子）を表す。但し、Ｙ^１〜Ｙ^１０のうち、隣接する２つがＣＲ^ａである場合、隣接するＣＲ^ａにおけるＲ^ａの一部同士が結合して環構造を形成していてもよい。
Ｒ^ａは、それぞれ独立に、水素原子、ハロゲン原子、シアノ基、置換もしくは無置換の炭素数１〜２０のアルキル基、置換もしくは無置換の炭素数１〜２０のアルコキシ基、置換もしくは無置換の炭素数１〜２０のハロアルキル基、置換もしくは無置換の炭素数１〜２０のハロアルコキシ基、置換もしくは無置換のシリル基、置換もしくは無置換の炭素数２〜２０のジアルキルアミノ基、置換もしくは無置換の炭素数１２〜３０のジアリールアミノ基、置換もしくは無置換の環形成炭素数６〜３０の芳香族炭化水素環基、置換もしくは無置換の環形成原子数５〜３０の複素環基を表し、複数のＲ^ａは、互いに同一でも異なっていてもよい。
ｓａ及びｔａは、それぞれ独立に、０〜５の整数を表し、ｓｂ及びｔｂは、それぞれ０〜４の整数を表し、ｕは０〜２の整数を表し、ｓａ＋ｓｂ＋ｔａ＋ｔｂ＋ｕは１〜５の整数である。
ｓａが１〜５の場合、Ａ^１と（Ｑ^１）_ｓａのＱ^１は結合している。ｓｂが１〜４の場合、Ｙ^１〜Ｙ^４の少なくとも１つと（Ｂ^１−Ｑ^１）_ｓｂのＢ^１は結合している。
ｔａが１〜５の場合、Ａ^２と（Ｑ^２）_ｔａのＱ^２は結合している。ｔｂが１〜４の場合、Ｙ^５〜Ｙ^８の少なくとも１つと（Ｂ^２−Ｑ^２）_ｔｂのＢ^２は結合している。
ｕが１〜２の場合Ｙ^９及びＹ^１０の少なくとも１つと（Ｃ−Ｑ^３）_ｕのＣは結合している。
Ｑ^１、Ｑ^２及びＱ^３は、それぞれ独立に、−Ａｚ−Ｗ_ｑを表す。
ｑは１〜４の整数を表す。
Ｑ^１が複数ある場合、複数のＱ^１は互いに同一でも異なっていてもよい。Ｑ^２が複数ある場合、複数のＱ^２は互いに同一でも異なっていてもよい。Ｑ^３が複数ある場合、複数のＱ^３は互いに同一でも異なっていてもよい。
上記Ａｚは下記式（Ｘ）で表される環の（ｑ＋１）価の基である。

（式（Ｘ）において、Ｚ^１〜Ｚ^５は、それぞれ独立に、窒素原子又はＣＲ^ｂを表す。
前記ＣＲ^ｂにおいて、Ｒ^ｂは、前記Ｒ^ａと同義である。但し、Ｚ^１〜Ｚ^５のうち、隣接する２つがＣＲ^ｂである場合、隣接するＣＲ^ｂにおけるＲ^ｂの一部同士が結合して環構造を形成していてもよい。
Ｒ^ｂが複数存在する場合、複数のＲ^ｂは互いに同一でも異なっていてもよい。）
Ａｚが複数ある場合、複数のＡｚは互いに同一でも異なっていてもよい。
Ｗは、置換基Ｘ、置換基Ｘで置換された環形成炭素数６〜３０の芳香族炭化水素基又は置換基Ｘで置換された環形成原子数５〜３０の複素環基を表す。ただし、置換基Ｘで置換された環形成炭素数６〜３０の芳香族炭化水素基及び置換基Ｘで置換された環形成原子数５〜３０の複素環基は、置換基Ｘ以外の置換基を有していてもよい。置換基Ｘは、ハメット則の置換基定数（σｐ（パラ））が正の値をとる基である。Ｗが複数ある場合、複数のＷは互いに同一でも異なっていてもよい。］
３．下記式（１）〜（６）のいずれかで表される有機エレクトロルミネッセンス素子用材料。

［式（Ｉ）中、
Ａ^１、Ａ^２、Ｂ¹、Ｂ^２及びＣは、それぞれ独立に、単結合、置換もしくは無置換の環形成炭素数６〜３０の芳香族炭化水素基、又は置換もしくは無置換の環形成原子数５〜３０の複素環基を表す。
Ｙ^１〜Ｙ^１０は、それぞれ独立に、Ｎ（窒素原子）又はＣＲ^ａ（Ｃは炭素原子）を表す。但し、Ｙ^１〜Ｙ^１０のうち、隣接する２つがＣＲ^ａである場合、隣接するＣＲ^ａにおけるＲ^ａの一部同士が結合して環構造を形成していてもよい。
Ｒ^ａは、それぞれ独立に、水素原子、ハロゲン原子、シアノ基、置換もしくは無置換の炭素数１〜２０のアルキル基、置換もしくは無置換の炭素数１〜２０のアルコキシ基、置換もしくは無置換の炭素数１〜２０のハロアルキル基、置換もしくは無置換の炭素数１〜２０のハロアルコキシ基、置換もしくは無置換のシリル基、置換もしくは無置換の炭素数２〜２０のジアルキルアミノ基、置換もしくは無置換の炭素数１２〜３０のジアリールアミノ基、置換もしくは無置換の環形成炭素数６〜３０の芳香族炭化水素環基、置換もしくは無置換の環形成原子数５〜３０の複素環基を表し、複数のＲ^ａは、互いに同一でも異なっていてもよい。
ｓａ及びｔａは、それぞれ独立に、０〜５の整数を表し、ｓｂ及びｔｂは、それぞれ０〜４の整数を表し、ｕは０〜２の整数を表し、ｓａ＋ｓｂ＋ｔａ＋ｔｂ＋ｕは１〜５の整数である。
ｓａが１〜５の場合、Ａ^１と（Ｑ^１）_ｓａのＱ^１は結合している。ｓｂが１〜４の場合、Ｙ^１〜Ｙ^４の少なくとも１つと（Ｂ^１−Ｑ^１）_ｓｂのＢ^１は結合している。
ｔａが１〜５の場合、Ａ^２と（Ｑ^２）_ｔａのＱ^２は結合している。ｔｂが１〜４の場合、Ｙ^５〜Ｙ^８の少なくとも１つと（Ｂ^２−Ｑ^２）_ｔｂのＢ^２は結合している。
ｕが１〜２の場合Ｙ^９及びＹ^１０の少なくとも１つと（Ｃ−Ｑ^３）_ｕのＣは結合している。
Ｑ^１、Ｑ^２及びＱ^３は、それぞれ独立に、−Ａｚ−Ｗ_ｑを表す。
ｑは１〜４の整数を表す。
Ｑ^１が複数ある場合、複数のＱ^１は互いに同一でも異なっていてもよい。Ｑ^２が複数ある場合、複数のＱ^２は互いに同一でも異なっていてもよい。Ｑ^３が複数ある場合、複数のＱ^３は互いに同一でも異なっていてもよい。
上記Ａｚは下記式（Ｘ）で表される環の（ｑ＋１）価の基である。

（式（Ｘ）において、Ｚ^１〜Ｚ^５は、それぞれ独立に、窒素原子又はＣＲ^ｂを表す。
前記ＣＲ^ｂにおいて、Ｒ^ｂは、前記Ｒ^ａと同義である。但し、Ｚ^１〜Ｚ^５のうち、隣接する２つがＣＲ^ｂである場合、隣接するＣＲ^ｂにおけるＲ^ｂの一部同士が結合して環構造を形成していてもよい。
Ｒ^ｂが複数存在する場合、複数のＲ^ｂは互いに同一でも異なっていてもよい。）
Ａｚが複数ある場合、複数のＡｚは互いに同一でも異なっていてもよい。
Ｗは、置換基Ｘ、置換基Ｘで置換された環形成炭素数６〜３０の芳香族炭化水素基又は置換基Ｘで置換された環形成原子数５〜３０の複素環基を表す。ただし、置換基Ｘで置換された環形成炭素数６〜３０の芳香族炭化水素基及び置換基Ｘで置換された環形成原子数５〜３０の複素環基は、置換基Ｘ以外の置換基を有していてもよい。置換基Ｘは、ハメット則の置換基定数（σｐ（パラ））が正の値をとる電子吸引基である。Ｗが複数ある場合、複数のＷは互いに同一でも異なっていてもよい。］
４．下記式（１−１）〜（６−１）のいずれかで表される１〜３のいずれかに記載の有機エレクトロルミネッセンス素子用材料。

［式（１−１）〜（６−１）中、
Ａ^１、Ａ^２、Ｙ^１〜Ｙ^１０、Ｑ^１、Ｑ^２はそれぞれ前記式（１）〜（６）と同様な基を表す。ｓａ及びｔａは、それぞれ独立に、０〜５の整数を表し、ｓａ＋ｔａは１〜５の整数である。］
５．前記Ａｚが、置換もしくは無置換の窒素原子数１〜３の含窒素六員環、又は置換もしくは無置換の窒素原子数１〜３の含窒素六員環を含む縮合多環の基である１〜４のいずれかに記載の有機エレクトロルミネッセンス素子用材料。
６．前記Ａｚが、置換もしくは無置換の窒素原子数１もしくは２の含窒素六員環、又は置換もしくは無置換の窒素原子数１もしくは２の含窒素六員環を含む縮合多環の基である１〜５のいずれかに記載の有機エレクトロルミネッセンス素子用材料。
７．前記Ａｚが、置換もしくは無置換のピリミジン環、置換もしくは無置換のピリジン環、置換もしくは無置換のキナゾリン環、及び置換もしくは無置換のキノリン環からなる群から選択される環の基である１〜６のいずれかに記載の有機エレクトロルミネッセンス素子用材料。
８．前記Ａｚが、置換もしくは無置換のピリミジン環、及び置換もしくは無置換のピリジン環から選択される環の基である１〜７のいずれかに記載の有機エレクトロルミネッセンス素子用材料。
９．前記ｓａ及びｔａが、それぞれ０又は１である１〜８のいずれかに記載の有機エレクトロルミネッセンス素子用材料。
１０．前記ｔａが、０である１〜９のいずれかに記載の有機エレクトロルミネッセンス素子用材料。
１１．前記ｓａ＋ｓｂ＋ｔａ＋ｔｂ＋ｕが１である１〜３のいずれかに記載の有機エレクトロルミネッセンス素子用材料。
１２．前記ｓａが１であり、前記ｔａが０であり、前記Ａ^２が、置換又は無置換の環形成炭素数６〜３０の芳香族炭化水素環基又は置換もしくは無置換の環形成原子数５〜３０の複素環基である、１〜１１のいずれかに記載の有機エレクトロルミネッセンス素子用材料。
１３．前記ｓａが１であり、前記Ａ^１が単結合である、１〜１２のいずれかに記載の有機エレクトロルミネッセンス素子用材料。
１４．前記置換基Ｘが、−ＣＮ、−Ｆ、−Ｃｌ、−Ｂｒ、−Ｉ、−ＣＯ_２Ｒ^Ｃ、−ＣＯＲ^Ｃ、−ＣＦ_３、−ＳＯ_２Ｒ^Ｃ、−ＮＯ_２からなる群から選択される、１〜１１のいずれかに記載の有機エレクトロルミネッセンス素子用材料。（Ｒ^Ｃは、それぞれ独立に、水素原子、置換もしくは無置換の環形成炭素数６〜３０の芳香族炭化水素基、置換もしくは無置換の環形成原子数５〜３０の複素環基、又は置換もしくは無置換の炭素数１〜３０のアルキル基を表す。）
１５．前記置換基Ｘが、−ＣＮ、−Ｆ、−ＣＦ_３、−ＣＯ_２Ｒ^Ｃ、−ＣＯＲ^Ｃ、−ＳＯ_２Ｒ^Ｃ、からなる群から選択される、１〜１４のいずれかに記載の有機エレクトロルミネッセンス素子用材料。
（Ｒ^Ｃは、それぞれ独立に、水素原子、置換もしくは無置換の環形成炭素数６〜３０の芳香族炭化水素基、置換もしくは無置換の環形成原子数５〜３０の複素環基、又は置換もしくは無置換の炭素数１〜３０のアルキル基を表す。）
１６．前記置換基Ｘが、−ＣＮ又は−Ｆである、１〜１５記載のいずれかに記載の有機エレクトロルミネッセンス素子用材料。
１７．前記置換基Ｘが、−ＣＮである、１〜１６記載のいずれかに記載の有機エレクトロルミネッセンス素子用材料。
１８．前記Ｗが、ＣＮ置換フェニル基、ＣＮ置換ビフェニル基、ＣＮ置換ナフチル基、ＣＮ置換ジフェニルフルオレニル基、ＣＮ置換スピロビフルオレニル基、ＣＮ置換ジメチルフルオレニル基、ＣＮ置換フェナントレニル基、ＣＮ置換トリフェニレニル基、ＣＮ置換ジベンゾフラニル基、又はＣＮ置換ジベンゾチオフェニル基である１〜１７のいずれかに記載の有機エレクトロルミネッセンス素子用材料。
１９．陰極と陽極との間に発光層を含む１以上の有機薄膜層を有し、前記有機薄膜層の少なくとも１層が、１〜１８のいずれかに記載の有機エレクトロルミネッセンス素子用材料を含有する有機エレクトロルミネッセンス素子。
２０．前記発光層が、前記有機エレクトロルミネッセンス素子用材料を含有する１９に記載の有機エレクトロルミネッセンス素子。
２１．前記発光層が燐光発光材料を含有し、前記燐光発光材料がイリジウム（Ｉｒ）、オスミウム（Ｏｓ）及び白金（Ｐｔ）から選択される金属原子のオルトメタル化錯体である１９又は２０に記載の有機エレクトロルミネッセンス素子。 According to the present invention, the following materials for organic EL elements and organic EL elements are provided.
1. The material for organic electroluminescent elements represented by either of following formula (1)-(6).

[In the formula (I),
A 1 , A 2 , B 1 , B 2 and C are each independently a single bond, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted ring forming atom. The heterocyclic group of several 5-30 is represented.
Y 1 to Y 10 each independently represent N (nitrogen atom) or CR a (C is a carbon atom). However, among the Y 1 to Y 10, when two adjacent is a CR a, it may be bonded to each other part of the R a in adjacent CR a to form a ring structure.
Each R a independently represents a hydrogen atom, a halogen atom, a cyano group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted group; A haloalkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted haloalkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted silyl group, a substituted or unsubstituted dialkylamino group having 2 to 20 carbon atoms, substituted or unsubstituted A substituted or unsubstituted diarylamino group having 12 to 30 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon ring group having 6 to 30 carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 30 ring atoms; The plurality of R a may be the same as or different from each other.
sa and ta each independently represents an integer of 0 to 5, sb and tb each represents an integer of 0 to 4, u represents an integer of 0 to 2, and sa + sb + ta + tb + u is an integer of 1 to 5. .
If sa is 1 to 5, A 1 and (Q 1) Q 1 of sa is attached. When sb is 1 to 4 , at least one of Y 1 to Y 4 is bonded to B 1 of (B 1 -Q 1 ) sb .
If ta is 1 to 5, Q 2 and A 2 (Q 2) ta is attached. If tb is 1 to 4, at least one (B 2 -Q 2) B 2 of tb of Y 5 to Y 8 are attached.
When u is 1 to 2, at least one of Y 9 and Y 10 and C of (CQ 3 ) u are bonded.
Q 1 , Q 2 and Q 3 each independently represent -Az-W q .
q represents the integer of 1-4.
If Q 1 is are multiple, multiple Q 1 is may be the same or different from each other. If Q 2 there is a plurality, the plurality of Q 2 is may be the same or different from each other. If Q 3 is plural, Q 3 are may be the same or different from each other.
Az is a (q + 1) -valent group of a ring represented by the following formula (X).

(In the formula ^(X), Z 1 ~Z ⁵ each independently represent a nitrogen atom or a CR ^b.
In the CR ^{b, R b} are as defined above ^{R a.} However, when two adjacent Z ^{1 to} Z ⁵ are CR ^b , a part of R ^b in adjacent CR ^b may be bonded to form a ring structure.
If the R ^b there are a plurality, a plurality of R ^b may be the same or different from each other. )
When there are a plurality of Az, the plurality of Az may be the same as or different from each other.
W represents a substituent X, an aromatic hydrocarbon group having 6 to 30 ring carbon atoms substituted with the substituent X, or a heterocyclic group having 5 to 30 ring atoms substituted with the substituent X. However, the aromatic hydrocarbon group having 6 to 30 ring carbon atoms substituted with the substituent X and the heterocyclic group having 5 to 30 ring atoms substituted with the substituent X are substituents other than the substituent X. You may have. The substituent X is an electron withdrawing group. When there are a plurality of Ws, the plurality of Ws may be the same as or different from each other. ]
2. The material for organic electroluminescent elements represented by either of following formula (1)-(6).

[In the formula (I),
A 1 , A 2 , B 1 , B 2 and C are each independently a single bond, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted ring forming atom. The heterocyclic group of several 5-30 is represented.
Y 1 to Y 10 each independently represent N (nitrogen atom) or CR a (C is a carbon atom). However, among the Y 1 to Y 10, when two adjacent is a CR a, it may be bonded to each other part of the R a in adjacent CR a to form a ring structure.
Each R a independently represents a hydrogen atom, a halogen atom, a cyano group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted group; A haloalkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted haloalkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted silyl group, a substituted or unsubstituted dialkylamino group having 2 to 20 carbon atoms, substituted or unsubstituted A substituted or unsubstituted diarylamino group having 12 to 30 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon ring group having 6 to 30 carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 30 ring atoms; The plurality of R a may be the same as or different from each other.
sa and ta each independently represents an integer of 0 to 5, sb and tb each represents an integer of 0 to 4, u represents an integer of 0 to 2, and sa + sb + ta + tb + u is an integer of 1 to 5. .
If sa is 1 to 5, A 1 and (Q 1) Q 1 of sa is attached. When sb is 1 to 4 , at least one of Y 1 to Y 4 is bonded to B 1 of (B 1 -Q 1 ) sb .
If ta is 1 to 5, Q 2 and A 2 (Q 2) ta is attached. If tb is 1 to 4, at least one (B 2 -Q 2) B 2 of tb of Y 5 to Y 8 are attached.
When u is 1 to 2, at least one of Y 9 and Y 10 and C of (CQ 3 ) u are bonded.
Q 1 , Q 2 and Q 3 each independently represent -Az-W q .
q represents the integer of 1-4.
If Q 1 is are multiple, multiple Q 1 is may be the same or different from each other. If Q 2 there is a plurality, the plurality of Q 2 is may be the same or different from each other. If Q 3 is plural, Q 3 are may be the same or different from each other.
Az is a (q + 1) -valent group of a ring represented by the following formula (X).

(In the formula ^(X), Z 1 ~Z ⁵ each independently represent a nitrogen atom or a CR ^b.
In the CR ^{b, R b} are as defined above ^{R a.} However, when two adjacent Z ^{1 to} Z ⁵ are CR ^b , a part of R ^b in adjacent CR ^b may be bonded to form a ring structure.
If the R ^b there are a plurality, a plurality of R ^b may be the same or different from each other. )
When there are a plurality of Az, the plurality of Az may be the same as or different from each other.
W represents a substituent X, an aromatic hydrocarbon group having 6 to 30 ring carbon atoms substituted with the substituent X, or a heterocyclic group having 5 to 30 ring atoms substituted with the substituent X. However, the aromatic hydrocarbon group having 6 to 30 ring carbon atoms substituted with the substituent X and the heterocyclic group having 5 to 30 ring atoms substituted with the substituent X are substituents other than the substituent X. You may have. The substituent X is a group whose Hammett's rule constant (σp (para)) takes a positive value. When there are a plurality of Ws, the plurality of Ws may be the same as or different from each other. ]
3. The material for organic electroluminescent elements represented by either of following formula (1)-(6).

[In the formula (I),
A 1 , A 2 , B 1 , B 2 and C are each independently a single bond, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted ring forming atom. The heterocyclic group of several 5-30 is represented.
Y 1 to Y 10 each independently represent N (nitrogen atom) or CR a (C is a carbon atom). However, among the Y 1 to Y 10, when two adjacent is a CR a, it may be bonded to each other part of the R a in adjacent CR a to form a ring structure.
Each R a independently represents a hydrogen atom, a halogen atom, a cyano group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted group; A haloalkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted haloalkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted silyl group, a substituted or unsubstituted dialkylamino group having 2 to 20 carbon atoms, substituted or unsubstituted A substituted or unsubstituted diarylamino group having 12 to 30 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon ring group having 6 to 30 carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 30 ring atoms; The plurality of R a may be the same as or different from each other.
sa and ta each independently represents an integer of 0 to 5, sb and tb each represents an integer of 0 to 4, u represents an integer of 0 to 2, and sa + sb + ta + tb + u is an integer of 1 to 5. .
If sa is 1 to 5, A 1 and (Q 1) Q 1 of sa is attached. When sb is 1 to 4 , at least one of Y 1 to Y 4 is bonded to B 1 of (B 1 -Q 1 ) sb .
If ta is 1 to 5, Q 2 and A 2 (Q 2) ta is attached. If tb is 1 to 4, at least one (B 2 -Q 2) B 2 of tb of Y 5 to Y 8 are attached.
When u is 1 to 2, at least one of Y 9 and Y 10 and C of (CQ 3 ) u are bonded.
Q 1 , Q 2 and Q 3 each independently represent -Az-W q .
q represents the integer of 1-4.
If Q 1 is are multiple, multiple Q 1 is may be the same or different from each other. If Q 2 there is a plurality, the plurality of Q 2 is may be the same or different from each other. If Q 3 is plural, Q 3 are may be the same or different from each other.
Az is a (q + 1) -valent group of a ring represented by the following formula (X).

(In the formula ^(X), Z 1 ~Z ⁵ each independently represent a nitrogen atom or a CR ^b.
In the CR ^{b, R b} are as defined above ^{R a.} However, when two adjacent Z ^{1 to} Z ⁵ are CR ^b , a part of R ^b in adjacent CR ^b may be bonded to form a ring structure.
If the R ^b there are a plurality, a plurality of R ^b may be the same or different from each other. )
When there are a plurality of Az, the plurality of Az may be the same as or different from each other.
W represents a substituent X, an aromatic hydrocarbon group having 6 to 30 ring carbon atoms substituted with the substituent X, or a heterocyclic group having 5 to 30 ring atoms substituted with the substituent X. However, the aromatic hydrocarbon group having 6 to 30 ring carbon atoms substituted with the substituent X and the heterocyclic group having 5 to 30 ring atoms substituted with the substituent X are substituents other than the substituent X. You may have. The substituent X is an electron withdrawing group in which the Hammett's rule substituent constant (σp (para)) takes a positive value. When there are a plurality of Ws, the plurality of Ws may be the same as or different from each other. ]
4). The organic electroluminescent element material in any one of 1-3 represented by either of following formula (1-1)-(6-1).

[In the formulas (1-1) to (6-1),
A ¹ , A ² , Y ^{1 to} Y ¹⁰ , Q ¹ and Q ² each represent the same group as in the above formulas (1) to (6). sa and ta each independently represent an integer of 0 to 5, and sa + ta is an integer of 1 to 5. ]
5. Az is a condensed polycyclic group containing a substituted or unsubstituted nitrogen-containing 6-membered ring having 1 to 3 nitrogen atoms, or a substituted or unsubstituted nitrogen-containing 6-membered ring having 1 to 3 nitrogen atoms. Material for organic electroluminescent elements in any one of -4.
6). Az is a condensed polycyclic group containing a substituted or unsubstituted nitrogen-containing 6-membered ring having 1 or 2 nitrogen atoms, or a substituted or unsubstituted nitrogen-containing 6-membered ring having 1 or 2 nitrogen atoms Material for organic electroluminescent elements in any one of -5.
7). Az is a ring group selected from the group consisting of a substituted or unsubstituted pyrimidine ring, a substituted or unsubstituted pyridine ring, a substituted or unsubstituted quinazoline ring, and a substituted or unsubstituted quinoline ring. 6. The material for an organic electroluminescence element according to any one of 6 above.
8). The material for an organic electroluminescence device according to any one of 1 to 7, wherein Az is a ring group selected from a substituted or unsubstituted pyrimidine ring and a substituted or unsubstituted pyridine ring.
9. The organic electroluminescent element material according to any one of 1 to 8, wherein sa and ta are 0 or 1, respectively.
10. The organic electroluminescence element material according to any one of 1 to 9, wherein ta is 0.
11. 4. The material for an organic electroluminescence element according to any one of 1 to 3, wherein sa + sb + ta + tb + u is 1.
12 The sa is 1, the ta is 0, and the A ² is a substituted or unsubstituted aromatic hydrocarbon ring group having 6 to 30 ring carbon atoms or a substituted or unsubstituted ring forming atom number of 5 to 5. The material for organic electroluminescent elements according to any one of 1 to 11, which is 30 heterocyclic groups.
13. The material for organic electroluminescent elements according to any one of 1 to 12, wherein the sa is 1 and the A ¹ is a single bond.
14 The substituent X is selected from the group consisting of —CN, —F, —Cl, —Br, —I, —CO ₂ R ^C , —COR ^C , —CF ₃ , —SO ₂ R ^C , —NO _2. The material for organic electroluminescent elements according to any one of 1 to 11. (R ^C are each independently a hydrogen atom, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, a substituted or unsubstituted ring atoms 5 to 30 heterocyclic group, or a substituted Alternatively, it represents an unsubstituted alkyl group having 1 to 30 carbon atoms.)
15. The substituent X ^{_{is, -CN, -F, -CF 3,}} -CO 2 R C, -COR C, -SO 2 R C, is selected from the group consisting of organic according to any one of 1 to 14 Electroluminescent element material.
(R ^C are each independently a hydrogen atom, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, a substituted or unsubstituted ring atoms 5 to 30 heterocyclic group, or a substituted Alternatively, it represents an unsubstituted alkyl group having 1 to 30 carbon atoms.)
16. The organic electroluminescent element material in any one of 1-15 whose said substituent X is -CN or -F.
17. The organic electroluminescent element material according to any one of 1 to 16, wherein the substituent X is -CN.
18. W is a CN-substituted phenyl group, a CN-substituted biphenyl group, a CN-substituted naphthyl group, a CN-substituted diphenylfluorenyl group, a CN-substituted spirobifluorenyl group, a CN-substituted dimethylfluorenyl group, a CN-substituted phenanthrenyl group, CN The material for organic electroluminescent elements according to any one of 1 to 17, which is a substituted triphenylenyl group, a CN-substituted dibenzofuranyl group, or a CN-substituted dibenzothiophenyl group.
19. An organic material having one or more organic thin film layers including a light emitting layer between a cathode and an anode, wherein at least one of the organic thin film layers contains the material for an organic electroluminescent element according to any one of 1 to 18 Electroluminescence element.
20. 20. The organic electroluminescence device according to 19, wherein the light emitting layer contains the material for an organic electroluminescence device.
21. 21. The organic according to 19 or 20, wherein the light emitting layer contains a phosphorescent material, and the phosphorescent material is an orthometalated complex of a metal atom selected from iridium (Ir), osmium (Os), and platinum (Pt). Electroluminescence element.

  ADVANTAGE OF THE INVENTION According to this invention, the organic EL element from which long-lived phosphorescence emission is obtained, and the organic electroluminescent element material for implement | achieving it can be provided.

FIG. 1 is a schematic cross-sectional view showing an example of the organic EL element of the present invention.

The organic EL device material of the present invention is a compound represented by any of the following formulas (1) to (6).

The above compound is a compound containing an indolocarbazole skeleton and a nitrogen-containing heterocyclic group (Az group possessed by Q ^{1 to} Q ³ described later) in the same molecule, and the nitrogen-containing heterocyclic group is an electron-withdrawing group or / and Hammett. Substituent X, which is a group having a positive substituent constant (σp (para)), an aromatic hydrocarbon group having 6 to 30 ring carbon atoms substituted with substituent X, or substituent X The heterocyclic group (W) having 5 to 30 ring atoms formed as a substituent. When the nitrogen-containing heterocyclic group has the substituent X or the substituent having the substituent X, the singlet energy (S1) of the compound is reduced and the structure is stabilized. As a result, the lifetime of the organic EL device using this compound is improved.

In the formulas (1) to (6), A ¹ , A ² , B ¹ , B ² and C are each independently a single bond, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring carbon atoms. Or a substituted or unsubstituted heterocyclic group having 5 to 30 ring atoms.

Y ^{1 to} Y ¹⁰ each independently represent N (nitrogen atom) or CR ^a (C is a carbon atom). ^However, among the Y 1 ^{to Y 10,} when two adjacent is a CR ^a, it may be bonded to each other part of the ^{R a} in adjacent CR ^a to form a ring structure.
Each R ^a is independently a hydrogen atom, a halogen atom, a trifluoromethyl group, a cyano group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, Substituted or unsubstituted haloalkyl group having 1 to 20 carbon atoms, substituted or unsubstituted haloalkoxy group having 1 to 20 carbon atoms, substituted or unsubstituted silyl group, substituted or unsubstituted dialkylamino group having 2 to 20 carbon atoms Group, substituted or unsubstituted diarylamino group having 12 to 30 carbon atoms, substituted or unsubstituted aromatic hydrocarbon ring group having 6 to 30 ring carbon atoms, substituted or unsubstituted ring atom having 5 to 30 ring atoms Represents a heterocyclic group. When there are a plurality of R ^{a s} , they may be the same as or different from each other.

sa and ta each independently represent an integer of 0 to 5, sb and tb each independently represent an integer of 0 to 4, u represents an integer of 0 to 2, and sa + sb + ta + tb + u represents 1 to 5 It is an integer.
If sa is 1 to 5, A 1 and (Q 1) Q 1 of sa is attached. When sb is 1 to 4 , at least one of Y 1 to Y 4 is bonded to B 1 of (B 1 -Q 1 ) sb .
If ta is 1 to 5, Q 2 and A 2 (Q 2) ta is attached. If tb is 1 to 4, at least one (B 2 -Q 2) B 2 of tb of Y 5 to Y 8 are attached.
When u is 1-2, at least one of Y 9 to Y 10 and C of (CQ 3 ) u are bonded.

Q ¹ , Q ² and Q ³ are each independently a group represented by -Az-W _q .
q represents the integer of 1-4.
If Q ¹ is are multiple, multiple Q ¹ is may be the same or different from each other. If Q ² there is a plurality, the plurality of Q ² is may be the same or different from each other. If Q ³ is plural, Q ³ are may be the same or different from each other.

Az is a (q + 1) -valent group of a ring represented by the following formula (X).

In Formula (X), Z ^{1 to} Z ⁵ each independently represent a nitrogen atom or CR ^b . R ^b represents the same group as R ^a described above. However, when two adjacent Z ^{1 to} Z ⁵ are CR ^b , a part of R ^b in adjacent CR ^b may be bonded to form a ring structure.
If the R ^b there are a plurality, a plurality of R ^b may be the same or different from each other.
When there are a plurality of Az, the plurality of Az may be the same as or different from each other.

Az includes (q + 1) -valent groups of isoquinoline ring, quinoxaline ring, phenanthridine ring, phenanthroline ring, pyridine ring, pyrazine ring, pyrimidine ring, pyridazine ring, triazine ring, quinazoline ring, quinoline ring and acridine ring. These rings may be substituted or unsubstituted.
Az is a condensed polycyclic group containing a substituted or unsubstituted nitrogen-containing 6-membered ring having 1 to 3 nitrogen atoms or a substituted or unsubstituted nitrogen-containing 6-membered ring having 1 to 3 nitrogen atoms. preferable.
Az is a condensed polycyclic group containing a substituted or unsubstituted nitrogen-containing 6-membered ring having 1 or 2 nitrogen atoms, or a substituted or unsubstituted nitrogen-containing 6-membered ring having 1 or 2 nitrogen atoms. Is preferred.
Specifically, Az is a ring group selected from the group consisting of a substituted or unsubstituted pyrimidine ring, a substituted or unsubstituted pyridine ring, a substituted or unsubstituted quinazoline ring, and a substituted or unsubstituted quinoline ring. In particular, a ring group selected from a substituted or unsubstituted pyrimidine ring and a substituted or unsubstituted pyridine ring is preferable.

Specific structural examples of Q ^{1 to} Q ³ are shown below.

Herein, R represents a substituent, said R ^a, the same meanings as those mentioned R ^b. R is preferably a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted dibenzofuranyl group, substituted or unsubstituted A substituted thiophenyl group is exemplified.
p represents an integer of 1 to 5.

W represents a substituent X, an aromatic hydrocarbon group having 6 to 30 ring carbon atoms substituted with the substituent X, or a heterocyclic group having 5 to 30 ring atoms substituted with the substituent X. However, the aromatic hydrocarbon group having 6 to 30 ring carbon atoms substituted with the substituent X and the heterocyclic group having 5 to 30 ring atoms substituted with the substituent X are substituents other than the substituent X. You may have. The substituent X is an electron withdrawing group.
Here, the substituent X is an electron-withdrawing group, a group having a positive Hammett's rule constant (σp (para)), or a positive Hammett's substituent constant (σp (para)). An electron withdrawing group.
When there are a plurality of Ws, the plurality of Ws may be the same as or different from each other.

In the present application, the electron-withdrawing group is also called an electron-accepting group, and means an atomic group that attracts electrons from a substituted atomic group by an inductive effect or a resonance effect in the electronic theory.
Examples of the electron withdrawing group include those having a positive Hammett's substituent constant (σp (para)).
In addition, although there exists an example which shows a positive value also in a phenyl group, in this application, it does not include in an electron withdrawing group.

  In the present invention, when an aromatic hydrocarbon group substituted with the substituent X is bonded to Az, a heterocyclic group substituted with the substituent X is bonded, or a substituent X is directly bonded, Due to the induction effect of the group X, the affinity (Af) of a compound having a structure in which Az is bonded at a specific position (particularly a light emitting material host) can be increased. As a result, by using the organic EL element material of the present invention for the organic EL element, the efficiency of the organic EL element is improved by improving the electron injection property. In addition, when the material of the present invention is used for the light emitting layer of the organic EL device, the electron barrier is increased in the hole transport layer adjacent to the light emitting layer, so that electrons are confined, and the electron in the hole injection / transport layer is By reducing the deterioration, the lifetime of the organic EL element can be improved.

Examples of the substituent X include -Cl (σp: +0.23), -Br (σp (para): +0.23), -F (σp: +0.06), -I (σp: +0.18) , -CO ₂ R ^C (σp: when R = Et +0.45), -COR ^C (σp: when R = Me +0.50), -CF ₃ (σp: +0.54), -CN (σp ^{_{: +0.66), - SO 2 R}} C (σp: +0.72 when _{R = Me), - NO 2} (σp: +0.78) , and the like.
R ^C is independently a hydrogen atom, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring carbon atoms, a substituted or unsubstituted heterocyclic group having 5 to 30 ring atoms, substituted or unsubstituted An unsubstituted alkyl group having 1 to 30 carbon atoms is represented.
The Hammett's rule substituent constant (σp (para)) is a value described in Iwanami Rikagaku Dictionary 5th edition, P1063, Hitomi Suzuki, Organic Chemistry Course 2, Organic Reaction II Aromatic Compound, P119, and the like.

Preferred substituents X are —CN, —F, —CF ₃ , —CO ₂ R ^C , because of chemical stability of the substituent (hard to decompose) and electrical stability (hard to generate radicals). -COR ^C, include _-SO 2 R ^C. Among these, when the molecular weight of the material is small, a decrease in vapor deposition temperature and an improvement in thermal stability can be expected, so -F or -CN is preferable, and -CN is particularly preferable.
When the substituent X is —F, the triplet energy (T1) of the compound can be maintained high. Therefore, when the material of the present invention is used as the host of the light emitting layer, the efficiency of the organic EL device can be maintained or improved. it can.
When the substituent X is —CN, the singlet energy (S1) of the compound can be reduced not only by the inductive effect but also by the resonance effect. Therefore, when the material of the present invention is used as the host of the light emitting layer, photochemical stability As a result, the lifetime of the organic EL element can be extended.

  More specifically, as W, CN-substituted phenyl group, CN-substituted biphenyl group, CN-substituted naphthyl group, CN-substituted diphenylfluorenyl group, CN-substituted spirobifluorenyl group, CN-substituted dimethylfluorenyl group, CN Examples thereof include a substituted phenanthrenyl group, a CN-substituted triphenylenyl group, a CN-substituted dibenzofuranyl group, and a CN-substituted dibenzothiophenyl group.

［式（１−１）〜（６−１）中、
Ａ^１、Ａ^２、Ｙ^１〜Ｙ^１０、Ｑ^１、Ｑ^２はそれぞれ上記式（１）〜（６）と同様な基を表す。ｓａ及びｔａは、それぞれ独立に、０〜５の整数を表し、ｓａ＋ｔａは１〜５の整数である。］ Of the above formulas (1) to (6), for example, a compound represented by any one of the following formulas (1-1) to (6-1) is preferable.

[In the formulas (1-1) to (6-1),
A ¹ , A ² , Y ^{1 to} Y ¹⁰ , Q ¹ and Q ² each represent a group similar to the above formulas (1) to (6). sa and ta each independently represent an integer of 0 to 5, and sa + ta is an integer of 1 to 5. ]

In the compounds represented by formulas (1-1) to (6-1), the structure is stabilized by the interaction between N of indolocarbazole and Az of Q ¹ and Q ^2. Life expectancy can be expected.
In addition, since the synthesis is simple, a high-purity material can be obtained, which is advantageous for extending the life of the light-emitting element.

In the formulas (1) to (6) or the formulas (1-1) to (6-1), compounds in which sa, sb, ta, tb and u are each 0 or 1 are preferable. This increases the triplet energy (T1), which is advantageous for increasing the efficiency of the light-emitting element.
A compound in which ta, tb and u are 0 is preferable. As a result, indolocarbazole HOMO (Highest
Occupied Molecular orbital) of the distribution and ^{Q 1} of Az of LUMO (Lowest Occupied
Since the separation from the molecular orbital distribution becomes clear, the energy difference (ΔST) between S1 and T1 of the compound is reduced, the carrier injection property of the organic EL element is improved, the voltage is lowered, and the life is extended. Can be expected.
A compound in which sa + sb + ta + tb + u is 1 is preferable. In this case, since the triplet energy (T1) of the compound is large, it is advantageous for improving the efficiency of the organic EL device. Further, the energy difference (ΔST) between S1 and T1 of the compound is reduced, the carrier injectability of the light emitting element is improved, the voltage is lowered, and the lifetime can be expected to be extended.
Sa is 1, ta is 0, and A ² is a substituted or unsubstituted aromatic hydrocarbon ring group having 6 to 30 ring carbon atoms or a substituted or unsubstituted ring forming atom number of 5 to 30. The compound which is the heterocyclic group of is preferable. Thus, as described above, the triplet energy (T1) of the compound is large, which is advantageous for increasing the efficiency of the organic EL device. Further, the energy difference (ΔST) between S1 and T1 of the compound is reduced, the carrier injectability of the organic EL element is improved, the voltage is lowered, and the lifetime can be expected to be extended. Furthermore, since the structure is stabilized by the interaction between N of indolocarbazole and Az of Q ¹ , the lifetime of the organic EL element can be expected to be extended. Further, since the synthesis is simplified, a high-purity material can be obtained, which is advantageous for extending the life of the organic EL element.
Further, as A ^2, aromatic hydrocarbon ring groups, selecting a heterocyclic group, more structural stable, which is advantageous to the long life of the organic EL element.
Further, sa is 1, Compound A ¹ is a single bond. This
The interaction between N of indolocarbazole and Az of Q ¹ is further enhanced and the structure is further stabilized, so that the lifetime of the organic EL element can be expected to be extended. In addition, since the synthesis becomes easier, a high-purity material can be obtained, which is advantageous for extending the life of the organic EL element.

Hereinafter, each group in Formula (1)-(6) mentioned above is demonstrated in detail.
Examples of the alkyl group having 1 to 20 carbon atoms or 1 to 30 carbon atoms (preferably 1 to 6 carbon atoms) include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, and s-butyl. Group, isobutyl group, t-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, n-tridecyl group, n-tetradecyl group, n-pentadecyl group, n-hexadecyl group, n-heptadecyl group, n-octadecyl group, neopentyl group, 1-methylpentyl group, cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl Group, cyclooctyl group, adamantyl group and the like, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, s-butyl , Isobutyl, t- butyl group, a cyclopentyl group, a cyclohexyl group is preferred.

  Examples of the halogen atom include fluorine, chlorine, bromine, iodine and the like, and fluorine is preferable.

  Examples of the alkoxy group having 1 to 20 carbon atoms include methoxy group, ethoxy group, propoxy group, pentyloxy group, hexyloxy group and the like. Preferably, it is a C1-C5 alkoxy group.

  Examples of the haloalkyl group having 1 to 20 carbon atoms include those in which one or more hydrogen atoms are substituted with halogen atoms in the above alkyl group. As the halogen atom, fluorine is preferred. A trifluoromethyl group, a 2,2-trifluoroethyl group, etc. are mentioned. Preferably, it is a C1-C5 haloalkyl group.

  Examples of the haloalkoxy group having 1 to 20 carbon atoms include those in which one or more hydrogen atoms are substituted with halogen atoms in the above alkoxy group. As the halogen atom, fluorine is preferred. Preferably, it is a C1-C5 haloalkoxy group.

Examples of the substituted or unsubstituted silyl group include a silyl group having 1 or more substituted or unsubstituted alkyl having 1 to 10 carbon atoms (alkylsilyl group), 1 substituted or unsubstituted aryl having 6 to 30 carbon atoms. Examples thereof include a silyl group (arylsilyl group) having the above or a silyl group having both an alkyl group and an aryl group.
Specifically, trimethylsilyl group, triethylsilyl group, tributylsilyl group, dimethylethylsilyl group, t-butyldimethylsilyl group, vinyldimethylsilyl group, propyldimethylsilyl group, dimethylisopropylsilyl group, dimethylpropylsilyl group, dimethylbutyl Examples include silyl group, dimethyl tertiary butyl silyl group, diethyl isopropyl silyl group, phenyl dimethyl silyl group, diphenyl methyl silyl group, diphenyl tertiary butyl silyl group, triphenyl silyl group, and the like. Trimethyl silyl group, triethyl silyl group, t- A butyldimethylsilyl group, a vinyldimethylsilyl group, and a propyldimethylsilyl group are preferred.

  Examples of the dialkylamino group having 2 to 20 carbon atoms include dimethylamino group, diethylamino group, di-n-propylamino group, diisopropylamino group, di-n-butylamino group, di-s-butylamino group, diisobutylamino group , Di-t-butylamino group, dicyclopentylamino group, dicyclohexylamino group and the like.

  Examples of the diarylamino group having 12 to 30 carbon atoms include diphenylamino group, dinaphthylamino group, dibiphenylamino group, difluorenylamino group, phenylnaphthylamino group, phenylbiphenylamino group, phenylfluorenylamino group, and biphenyl. Examples include a fluorenylamino group.

Examples of the aromatic hydrocarbon group having 6 to 30 ring carbon atoms (preferably 6 to 14 ring carbon atoms) include non-condensed aromatic hydrocarbon groups and condensed aromatic hydrocarbon groups. Specifically, in the case of a monovalent group, phenyl group, naphthyl group, phenanthryl group, biphenyl group, terphenyl group, quarterphenyl group, fluoranthenyl group, triphenylenyl group, phenanthrenyl group, fluorenyl group, spirofluorenyl group Group, 9,9-diphenylfluorenyl group, 9,9′-spirobi [9H-fluoren] -2-yl group, 9,9-dimethylfluorenyl group, benzo [c] phenanthrenyl group, benzo [a] Examples include triphenylenyl group, naphtho [1,2-c] phenanthrenyl group, naphtho [1,2-a] triphenylenyl group, dibenzo [a, c] triphenylenyl group, benzo [b] fluoranthenyl group, phenyl group, Naphtyl group, biphenyl group, terphenyl group, phenanthryl group, triphenylenyl group, fluorenyl Group, spirobifluorenyl group and fluoranthenyl group are preferred.
Examples of the divalent or higher aromatic hydrocarbon group include a divalent or higher group derived by removing a hydrogen atom from the aryl group.

Examples of the heterocyclic group having 5 to 30 ring atoms (preferably 5 to 14 ring atoms) include non-fused heterocyclic groups and fused heterocyclic groups.
More specifically, pyrrole ring, isoindole ring, benzofuran ring, isobenzofuran ring, dibenzothiophene ring, isoquinoline ring, quinoxaline ring, phenanthridine ring, phenanthroline ring, pyridine ring, pyrazine ring, pyrimidine ring, pyridazine ring, Triazine ring, indole ring, quinoline ring, acridine ring, pyrrolidine ring, dioxane ring, piperidine ring, morpholine ring, piperazine ring, furan ring, thiophene ring, oxazole ring, oxadiazole ring, benzoxazole ring, thiazole ring, thiadiazole Examples include a ring, a benzothiazole ring, a triazole ring, an imidazole ring, a benzimidazole ring, a pyran ring, a dibenzofuran ring, a benzo [c] dibenzofuran ring, and groups formed from these derivatives. Nzochiofen rings and groups formed from these derivatives.

  In the case of “substituted or unsubstituted”, examples of the optional substituent include a halogen atom (fluorine, chlorine, bromine, iodine), a cyano group, an alkyl group having 1 to 20 carbon atoms (preferably 1 to 6), and 3 carbon atoms. -20 (preferably 5-12) cycloalkyl group, C1-C20 (preferably 1-5) alkoxy group, C1-C20 (preferably 1-5) haloalkyl group, C1-C1 20 (preferably 1-5) haloalkoxy group, alkylsilyl group having 1-10 carbon atoms (preferably 1-5), aryl group having 6-30 ring carbon atoms (preferably 6-18) (aromatic Hydrocarbon group), aryloxy group having 6 to 30 (preferably 6 to 18) ring-forming carbon atoms, arylsilyl group having 6 to 30 (preferably 6 to 18) carbon atoms, and 7 to 30 carbon atoms (preferably 7). ~ 20) Aralkyl , And ring atoms 5 to 30 (preferably 5 to 18) heteroaryl group (heterocyclic group). These substituents may be further substituted with the above-mentioned arbitrary substituents.

Examples of the optional substituent include an alkyl group, an alkoxy group, a haloalkyl group, a haloalkoxy group, a substituted silyl group, an aromatic hydrocarbon group, and a heterocyclic group as described above.
Examples of the aryloxy group include those in which one hydrogen atom of a non-condensed aromatic hydrocarbon group and a condensed aromatic hydrocarbon group is substituted with an —O— group.
Examples of the aralkyl group include those in which one hydrogen atom of a non-condensed aromatic hydrocarbon group or a condensed aromatic hydrocarbon group is substituted with an alkyl group.

  Of the above optional substituents, a fluorine atom, a cyano group, an alkyl group, a cycloalkyl group, an alkylsilyl group, an aryl group (aromatic hydrocarbon group), and a heteroaryl group (heterocyclic group) are particularly preferable.

  In the present specification, “carbon number ab” in the expression “XX group having a substituted or unsubstituted carbon number ab” represents the carbon number in the case where the XX group is unsubstituted. The number of carbon atoms of the substituent when the XX group is substituted is not included. In the organic EL device material of the present invention, the hydrogen atom includes isotopes having different numbers of neutrons, that is, light hydrogen (protium), deuterium (triuterium), and tritium (tritium).

Although the specific example of the organic EL element material of this invention is described below, it is not limited to the following compound.

Next, an embodiment of the organic EL element of the present invention will be described.
The organic EL device of the present invention has an organic thin film layer containing a light emitting layer between a cathode and an anode, and at least one of the organic thin film layers contains the above-described organic EL device material of the present invention. Thus, the life of the organic EL element can be extended.
Examples of the organic thin film layer containing the organic EL device material of the present invention include a hole transport layer, a light emitting layer, an electron transport layer, a space layer, and a barrier layer, but are not limited thereto. Absent. The material for an organic EL device of the present invention is preferably contained in the light emitting layer, and particularly preferably used as a host material for the light emitting layer. The light emitting layer preferably contains a fluorescent light emitting material or a phosphorescent light emitting material, and particularly preferably contains a phosphorescent light emitting material. Furthermore, the organic EL device material of the present invention is also suitable as a barrier layer.

  The organic EL element of the present invention may be a fluorescent or phosphorescent monochromatic light emitting element, a fluorescent / phosphorescent hybrid white light emitting element, or a simple type having a single light emitting unit. A tandem type having a plurality of light emitting units may be used, and among them, a phosphorescent type is preferable. Here, the “light emitting unit” refers to a minimum unit that includes one or more organic layers, one of which is a light emitting layer, and can emit light by recombination of injected holes and electrons.

Accordingly, typical element configurations of simple organic EL elements include the following element configurations.
(1) Anode / light emitting unit / cathode The above light emitting unit may be a laminated type having a plurality of phosphorescent light emitting layers and fluorescent light emitting layers. In that case, the light emitting unit is generated by a phosphorescent light emitting layer between the light emitting layers. In order to prevent the excitons from diffusing into the fluorescent light emitting layer, a space layer may be provided. A typical layer structure of the light emitting unit is shown below.
(A) Hole transport layer / light emitting layer (/ electron transport layer)
(B) Hole transport layer / first phosphorescent light emitting layer / second phosphorescent light emitting layer (/ electron transport layer)
(C) Hole transport layer / phosphorescent layer / space layer / fluorescent layer (/ electron transport layer)
(D) Hole transport layer / first phosphorescent light emitting layer / second phosphorescent light emitting layer / space layer / fluorescent light emitting layer (/ electron transport layer)
(E) Hole transport layer / first phosphorescent light emitting layer / space layer / second phosphorescent light emitting layer / space layer / fluorescent light emitting layer (/ electron transport layer)
(F) Hole transport layer / phosphorescent layer / space layer / first fluorescent layer / second fluorescent layer (/ electron transport layer)
(G) Hole transport layer / electron barrier layer / light emitting layer (/ electron transport layer)
(H) Hole transport layer / light emitting layer / hole barrier layer (/ electron transport layer)
(I) Hole transport layer / fluorescent light emitting layer / triplet barrier layer (/ electron transport layer)

Each phosphorescent or fluorescent light-emitting layer may have a different emission color. Specifically, in the laminated light emitting layer (d), hole transport layer / first phosphorescent light emitting layer (red light emitting) / second phosphorescent light emitting layer (green light emitting) / space layer / fluorescent light emitting layer (blue light emitting) / Examples include a layer configuration such as an electron transport layer.
An electron barrier layer may be appropriately provided between each light emitting layer and the hole transport layer or space layer. Further, a hole blocking layer may be appropriately provided between each light emitting layer and the electron transport layer. By providing an electron barrier layer or a hole barrier layer, electrons or holes can be confined in the light emitting layer, the recombination probability of charges in the light emitting layer can be increased, and the lifetime can be improved.

The following element structure can be mentioned as a typical element structure of a tandem type organic EL element.
(2) Anode / first light emitting unit / intermediate layer / second light emitting unit / cathode Here, as the first light emitting unit and the second light emitting unit, for example, the same light emitting unit as that described above is selected independently. can do.
The intermediate layer is generally called an intermediate electrode, an intermediate conductive layer, a charge generation layer, an electron extraction layer, a connection layer, or an intermediate insulating layer, and has electrons in the first light emitting unit and holes in the second light emitting unit. A known material structure to be supplied can be used.

  In FIG. 1, schematic structure of an example of the organic EL element of this invention is shown. The organic EL element 1 includes a substrate 2, an anode 3, a cathode 4, and a light emitting unit 10 disposed between the anode 3 and the cathode 4. The light emitting unit 10 includes a light emitting layer 5 including at least one phosphorescent light emitting layer including a phosphorescent host material and a phosphorescent dopant. A hole injection / transport layer 6 or the like may be formed between the light emitting layer 5 and the anode 3, and an electron injection / transport layer 7 or the like may be formed between the light emitting layer 5 and the cathode 4. Further, an electron barrier layer may be provided on the anode 3 side of the light emitting layer 5, and a hole barrier layer may be provided on the cathode 4 side of the light emitting layer 5. Thereby, electrons and holes can be confined in the light emitting layer 5, and the exciton generation probability in the light emitting layer 5 can be increased.

  In this specification, a host combined with a fluorescent dopant is referred to as a fluorescent host, and a host combined with a phosphorescent dopant is referred to as a phosphorescent host. The fluorescent host and the phosphorescent host are not distinguished only by the molecular structure. That is, the phosphorescent host means a material constituting a phosphorescent light emitting layer containing a phosphorescent dopant, and does not mean that it cannot be used as a material constituting a fluorescent light emitting layer. The same applies to the fluorescent host.

(substrate)
The organic EL element of the present invention is produced on a translucent substrate. The light-transmitting substrate is a substrate that supports the organic EL element, and is preferably a smooth substrate having a light transmittance in the visible region of 400 nm to 700 nm of 50% or more. Specifically, a glass plate, a polymer plate, etc. are mentioned. Examples of the glass plate include those made of soda lime glass, barium / strontium-containing glass, lead glass, aluminosilicate glass, borosilicate glass, barium borosilicate glass, quartz and the like as raw materials. Examples of the polymer plate include those using polycarbonate, acrylic, polyethylene terephthalate, polyether sulfide, polysulfone and the like as raw materials.

(anode)
The anode of the organic EL element plays a role of injecting holes into the hole transport layer or the light emitting layer, and it is effective to use a material having a work function of 4.5 eV or more. Specific examples of the anode material include indium tin oxide alloy (ITO), tin oxide (NESA), indium zinc oxide, gold, silver, platinum, copper, and the like. The anode can be produced by forming a thin film of these electrode materials by a method such as vapor deposition or sputtering. When light emitted from the light emitting layer is extracted from the anode, it is preferable that the transmittance of light in the visible region of the anode is greater than 10%. The sheet resistance of the anode is preferably several hundred Ω / □ or less. The film thickness of the anode depends on the material, but is usually selected in the range of 10 nm to 1 μm, preferably 10 nm to 200 nm.

(cathode)
The cathode plays a role of injecting electrons into the electron injection layer, the electron transport layer or the light emitting layer, and is preferably formed of a material having a small work function. The cathode material is not particularly limited, and specifically, indium, aluminum, magnesium, magnesium-indium alloy, magnesium-aluminum alloy, aluminum-lithium alloy, aluminum-scandium-lithium alloy, magnesium-silver alloy and the like can be used. Similarly to the anode, the cathode can be produced by forming a thin film by a method such as vapor deposition or sputtering. Moreover, you may take out light emission from the cathode side as needed.

(Light emitting layer)
An organic layer having a light emitting function, and when a doping system is employed, includes a host material and a dopant material. At this time, the host material mainly has a function of encouraging recombination of electrons and holes and confining excitons in the light emitting layer, and the dopant material efficiently emits excitons obtained by recombination. It has a function.
In the case of a phosphorescent element, the host material mainly has a function of confining excitons generated by the dopant in the light emitting layer.

Here, the light emitting layer employs, for example, a double host (also referred to as host / cohost) that adjusts the carrier balance in the light emitting layer by combining an electron transporting host and a hole transporting host. The light emitting layer preferably contains a first host material and a second host material, and the first host material is preferably the organic EL device material of the present invention.
Moreover, you may employ | adopt the double dopant from which each dopant light-emits by putting in 2 or more types of dopant materials with a high quantum yield. Specifically, a mode in which yellow emission is realized by co-evaporating a host, a red dopant, and a green dopant to make the light emitting layer common is used.

The above light-emitting layer is a laminate in which a plurality of light-emitting layers are stacked, so that electrons and holes are accumulated at the light-emitting layer interface, and the recombination region is concentrated at the light-emitting layer interface to improve quantum efficiency. Can do.
The ease of injecting holes into the light emitting layer may be different from the ease of injecting electrons, and the hole transport ability and electron transport ability expressed by the mobility of holes and electrons in the light emitting layer may be different. May be different.

The light emitting layer can be formed by a known method such as a vapor deposition method, a spin coating method, or an LB method (Langmuir Broadgett method). The light emitting layer can also be formed by thinning a solution obtained by dissolving a binder such as a resin and a material compound in a solvent by a spin coating method or the like.
The light emitting layer is preferably a molecular deposited film. The molecular deposited film is a thin film formed by deposition from a material compound in a gas phase state or a film formed by solidifying from a material compound in a solution state or a liquid phase state. The thin film (molecular accumulation film) formed by the LB method can be classified by the difference in the aggregation structure and the higher-order structure, and the functional difference resulting therefrom.

The dopant material is selected from known fluorescent dopants exhibiting fluorescent emission or phosphorescent dopants exhibiting phosphorescent emission.
The fluorescent dopant is selected from fluoranthene derivatives, pyrene derivatives, arylacetylene derivatives, fluorene derivatives, boron complexes, perylene derivatives, oxadiazole derivatives, anthracene derivatives, chrysene derivatives, and the like. Preferably, a fluoranthene derivative, a pyrene derivative, and a boron complex are used.

  The phosphorescent dopant (phosphorescent material) that forms the light emitting layer is a compound that can emit light from the triplet excited state, and is not particularly limited as long as it emits light from the triplet excited state, but Ir, Pt, Os, Au, Cu, An organometallic complex containing at least one metal selected from Re and Ru and a ligand is preferable. The ligand preferably has an ortho metal bond. A metal complex containing a metal atom selected from Ir, Os and Pt is preferred in that the phosphorescent quantum yield is high and the external quantum efficiency of the light emitting device can be further improved, and an iridium complex, an osmium complex, or a platinum complex. Are more preferable, iridium complexes and platinum complexes are more preferable, and orthometalated iridium complexes are particularly preferable.

  There is no restriction | limiting in particular in content in the light emitting layer of a phosphorescent dopant, Although it can select suitably according to the objective, For example, 0.1-70 mass% is preferable and 1-30 mass% is more preferable. If the phosphorescent dopant content is 0.1% by mass or more, sufficient light emission can be obtained, and if it is 70% by mass or less, concentration quenching can be avoided.

Specific examples of preferred organometallic complexes as phosphorescent dopants are shown below.

  The phosphorescent host is a compound having a function of efficiently emitting the phosphorescent dopant by efficiently confining the triplet energy of the phosphorescent dopant in the light emitting layer. The organic EL device material of the present invention is suitable as a phosphorescent host. The light emitting layer may contain 1 type of organic EL element material of this invention, and may contain 2 or more types of organic EL element material of this invention.

  When the organic EL device material of the present invention is used as the host material of the light emitting layer, the emission wavelength of the phosphorescent dopant material contained in the light emitting layer is not particularly limited. Among these, at least one of the phosphorescent dopant materials contained in the light emitting layer preferably has a peak emission wavelength of 490 nm to 700 nm, and more preferably 490 nm to 650 nm. As a luminescent color of a light emitting layer, red, yellow, and green are preferable, for example. By using the compound of the present invention as a host material and doping a phosphorescent dopant material having such an emission wavelength to form a light emitting layer, a long-life organic EL device can be obtained.

In the organic EL device of the present invention, a compound other than the material for the organic EL device of the present invention can be appropriately selected as the phosphorescent host according to the purpose.
The organic EL device material of the present invention and other compounds may be used in combination as a phosphorescent host material in the same light emitting layer, and when there are a plurality of light emitting layers, the phosphorescent host of one of the light emitting layers. The material for an organic EL device of the present invention may be used as a material, and a compound other than the material for an organic EL device of the present invention may be used as a phosphorescent host material for another light emitting layer. Moreover, the organic EL device material of the present invention can be used for organic layers other than the light emitting layer. In that case, a compound other than the organic EL device material of the present invention is used as the phosphorescent host of the light emitting layer. May be.

  Specific examples of compounds other than the organic EL device material of the present invention and suitable as a phosphorescent host include carbazole derivatives, triazole derivatives, oxazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives, Pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives, aromatic tertiary amine compounds, styrylamine compounds, aromatic dimethylidene compounds, porphyrins Compounds, anthraquinodimethane derivatives, anthrone derivatives, diphenylquinone derivatives, thiopyran dioxide derivatives, carbodiimide derivatives, fluorenylidene meta Derivatives, distyrylpyrazine derivatives, heterocyclic tetracarboxylic anhydrides such as naphthaleneperylene, phthalocyanine derivatives, metal complexes of 8-quinolinol derivatives, metal phthalocyanines, metal complexes having benzoxazole and benzothiazole as ligands Various metal complexes Polysilane compounds, poly (N-vinylcarbazole) derivatives, aniline copolymers, thiophene oligomers, conductive polymer oligomers such as polythiophene, polythiophene derivatives, polyphenylene derivatives, polyphenylene vinylene derivatives, polyfluorene derivatives, etc. Examples thereof include molecular compounds. A phosphorescent host may be used independently and may use 2 or more types together. Specific examples include the following compounds.

When the light emitting layer contains the first host material and the second host material, the organic EL element material of the present invention is used as the first host material, and the organic EL element material other than the organic EL element material of the present invention is used as the second host material. A compound may be used. In the present invention, the terms “first host material” and “second host material” mean that the plurality of host materials contained in the light emitting layer have different structures from each other. It is not specified by the material content.
It does not specifically limit as said 2nd host material, It is a compound other than the organic EL element material of this invention, and the same thing as the above-mentioned compound as a compound suitable as a phosphorescent host is mentioned. As the second host material, a compound having no cyano group is preferable. The second host is preferably a carbazole derivative, arylamine derivative, fluorenone derivative, or aromatic tertiary amine compound.

  The thickness of the light emitting layer is preferably 5 to 50 nm, more preferably 7 to 50 nm, and still more preferably 10 to 50 nm. When the thickness is 5 nm or more, it is easy to form a light emitting layer, and when the thickness is 50 nm or less, an increase in driving voltage is avoided.

(Electron donating dopant)
The organic EL device of the present invention preferably has an electron donating dopant in the interface region between the cathode and the light emitting unit. According to such a configuration, it is possible to improve the light emission luminance and extend the life of the organic EL element. Here, the electron donating dopant means a material containing a metal having a work function of 3.8 eV or less, and specific examples thereof include alkali metals, alkali metal complexes, alkali metal compounds, alkaline earth metals, alkaline earths. Examples thereof include at least one selected from metal complexes, alkaline earth metal compounds, rare earth metals, rare earth metal complexes, rare earth metal compounds, and the like.

  Examples of the alkali metal include Na (work function: 2.36 eV), K (work function: 2.28 eV), Rb (work function: 2.16 eV), Cs (work function: 1.95 eV), and the like. A function of 2.9 eV or less is particularly preferable. Of these, K, Rb, and Cs are preferred, Rb and Cs are more preferred, and Cs is most preferred. Examples of the alkaline earth metal include Ca (work function: 2.9 eV), Sr (work function: 2.0 eV to 2.5 eV), Ba (work function: 2.52 eV), and the like. The thing below 9 eV is especially preferable. Examples of rare earth metals include Sc, Y, Ce, Tb, Yb, and the like, and those having a work function of 2.9 eV or less are particularly preferable.

Examples of the alkali metal compound include alkali oxides such as Li ₂ O, Cs ₂ O, and K ₂ O, and alkali halides such as LiF, NaF, CsF, and KF, and LiF, Li ₂ O, and NaF are preferable. Examples of the alkaline earth metal compound include BaO, SrO, CaO, Ba _x Sr _1-x O (0 <x <1), Ba _x Ca _1-x O (0 <x <1), and the like obtained by mixing these. BaO, SrO, and CaO are preferable. The rare earth metal _{compound, YbF 3, ScF 3, ScO} 3, Y 2 O 3, Ce 2 O 3, GdF 3, TbF 3 and the _{like, YbF 3, ScF 3, TbF} 3 are preferable.

  The alkali metal complex, alkaline earth metal complex, and rare earth metal complex are not particularly limited as long as each metal ion contains at least one of an alkali metal ion, an alkaline earth metal ion, and a rare earth metal ion. The ligands include quinolinol, benzoquinolinol, acridinol, phenanthridinol, hydroxyphenyl oxazole, hydroxyphenyl thiazole, hydroxydiaryl thiadiazole, hydroxydiaryl thiadiazole, hydroxyphenylpyridine, hydroxyphenylbenzimidazole, hydroxybenzotriazole, Hydroxyfulborane, bipyridyl, phenanthroline, phthalocyanine, porphyrin, cyclopentadiene, β-diketones, azomethines, and derivatives thereof are preferred, but are not limited thereto.

  As an addition form of the electron donating dopant, it is preferable to form a layered or island shape in the interface region. As a forming method, while depositing an electron donating dopant by resistance heating vapor deposition, an organic compound (light emitting material or electron injecting material) that forms an interface region is simultaneously deposited, and the electron donating dopant is dispersed in the organic compound. Is preferred. The dispersion concentration is organic compound: electron-donating dopant = 100: 1 to 1: 100, preferably 5: 1 to 1: 5 in molar ratio.

In the case where the electron donating dopant is formed in a layered form, after forming the light emitting material or the electron injecting material, which is an organic layer at the interface, in a layered form, the reducing dopant is vapor-deposited by a resistance heating vapor deposition method. .1 nm to 15 nm. When the electron donating dopant is formed in an island shape, after forming the light emitting material and the electron injecting material, which are organic layers at the interface, in an island shape, the electron donating dopant is deposited by resistance heating vapor deposition alone, preferably The island is formed with a thickness of 0.05 nm to 1 nm.
In the organic EL device of the present invention, the ratio of the main component to the electron donating dopant is preferably in the molar ratio of main component: electron donating dopant = 5: 1 to 1: 5, and 2: 1 to 1: 2. More preferably.

(Electron transport layer)
The electron transport layer is an organic layer formed between the light emitting layer and the cathode, and has a function of transporting electrons from the cathode to the light emitting layer. When the electron transport layer is composed of a plurality of layers, an organic layer close to the cathode may be defined as an electron injection layer. The electron injection layer has a function of efficiently injecting electrons from the cathode into the organic layer unit.

As the electron transporting material used for the electron transporting layer, an aromatic heterocyclic compound containing one or more heteroatoms in the molecule is preferably used, and a nitrogen-containing ring derivative is particularly preferable. The nitrogen-containing ring derivative is preferably an aromatic ring having a nitrogen-containing 6-membered ring or 5-membered ring skeleton, or a condensed aromatic ring compound having a nitrogen-containing 6-membered ring or 5-membered ring skeleton.
As this nitrogen-containing ring derivative, for example, a nitrogen-containing ring metal chelate complex represented by the following formula (A) is preferable.

R ^{2 to} R ⁷ in the formula (A) which is a nitrogen-containing ring metal chelate complex are each independently a hydrogen atom, a deuterium atom, a halogen atom, a hydroxyl group, an amino group, a hydrocarbon group having 1 to 40 carbon atoms, An alkoxy group having 1 to 40 carbon atoms, an aryloxy group having 6 to 50 carbon atoms, an alkoxycarbonyl group, or an aromatic heterocyclic group having 5 to 50 ring carbon atoms, which may be substituted. .

Examples of the halogen atom include fluorine, chlorine, bromine, iodine and the like.
Examples of the amino group which may be substituted include an alkylamino group, an arylamino group and an aralkylamino group.
The alkylamino group and the aralkylamino group are represented as —NQ ¹ Q ² . Q ¹ and Q ² each independently represent an alkyl group having 1 to 20 carbon atoms or an aralkyl group having 1 to 20 carbon atoms. One of Q ¹ and Q ² may be a hydrogen atom or a deuterium atom.
The arylamino group is represented as —NAr ¹ Ar ^2, and Ar ¹ and Ar ² each independently represent a non-condensed aromatic hydrocarbon group or a condensed aromatic hydrocarbon group having 6 to 50 carbon atoms. One of Ar ¹ and Ar ² may be a hydrogen atom or a deuterium atom.

The hydrocarbon group having 1 to 40 carbon atoms includes an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, and an aralkyl group.
The alkoxycarbonyl group is represented as —COOY ′, and Y ′ represents an alkyl group having 1 to 20 carbon atoms.
M is aluminum (Al), gallium (Ga) or indium (In), and is preferably In.
L is a group represented by the following formula (A ′) or (A ″).

In formula (A ′), R ^{8 to} R ¹² are each independently a hydrogen atom, a deuterium atom, or a substituted or unsubstituted hydrocarbon group having 1 to 40 carbon atoms, and groups adjacent to each other are cyclic structures May be formed. In the formula (A ″), R ^{13 to} R ²⁷ are each independently a hydrogen atom, a deuterium atom, or a substituted or unsubstituted hydrocarbon group having 1 to 40 carbon atoms, and groups adjacent to each other are An annular structure may be formed.

In the formula (A), the hydrocarbon group having 1 to 40 carbon atoms represented by R ^{8 to} R ¹² and R ^{13 to} R ^{27 in the} formula (A ′) and the formula (A ″) is a nitrogen-containing ring metal chelate complex. The divalent group in the case where R ^{8 to} R ¹² and the groups adjacent to R ^{13 to} R ²⁷ form a cyclic structure is the same as the hydrocarbon group represented by R ^{2 to} R ⁷ of Examples include methylene group, pentamethylene group, hexamethylene group, diphenylmethane-2,2′-diyl group, diphenylethane-3,3′-diyl group, diphenylpropane-4,4′-diyl group and the like.

  As the electron transport compound used for the electron transport layer, 8-hydroxyquinoline or a metal complex of its derivative, an oxadiazole derivative, and a nitrogen-containing heterocyclic derivative are preferable. As a specific example of the metal complex of 8-hydroxyquinoline or a derivative thereof, a metal chelate oxinoid compound containing a chelate of oxine (generally 8-quinolinol or 8-hydroxyquinoline), for example, tris (8-quinolinol) aluminum is used. Can do. And as an oxadiazole derivative, the following can be mentioned.

In the above formula, Ar ¹⁷ , Ar ¹⁸ , Ar ¹⁹ , Ar ²¹ , Ar ²² and Ar ²⁵ each represent a substituted or unsubstituted aromatic hydrocarbon group having 6 to 50 carbon atoms or a condensed aromatic hydrocarbon group, Ar ¹⁷ and Ar ¹⁸ , Ar ¹⁹ and Ar ²¹ , Ar ²² and Ar ²⁵ may be the same or different. Examples of the aromatic hydrocarbon group or the condensed aromatic hydrocarbon group include a phenyl group, a naphthyl group, a biphenyl group, an anthranyl group, a perylenyl group, and a pyrenyl group. Examples of these substituents include an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, and a cyano group.

Ar ²⁰ , Ar ²³ and Ar ²⁴ each represent a substituted or unsubstituted divalent aromatic hydrocarbon group or condensed aromatic hydrocarbon group having 6 to 50 carbon atoms, and Ar ²³ and Ar ²⁴ are identical to each other. But it can be different. Examples of the divalent aromatic hydrocarbon group or condensed aromatic hydrocarbon group include a phenylene group, a naphthylene group, a biphenylene group, an anthranylene group, a peryleneylene group, and a pyrenylene group. Examples of these substituents include an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, and a cyano group.

  As these electron transfer compounds, those having good thin film forming properties are preferably used. Specific examples of these electron transfer compounds include the following.

  The nitrogen-containing heterocyclic derivative as the electron transfer compound is a nitrogen-containing heterocyclic derivative composed of an organic compound having the following formula, and includes a nitrogen-containing compound that is not a metal complex. Examples thereof include a 5-membered ring or 6-membered ring containing a skeleton represented by the following formula (B) and a structure represented by the following formula (C).

In the formula (C), X represents a carbon atom or a nitrogen atom. Z ₁ and Z ₂ each independently represents an atomic group capable of forming a nitrogen-containing heterocycle.

  The nitrogen-containing heterocyclic derivative is more preferably an organic compound having a nitrogen-containing aromatic polycyclic group consisting of a 5-membered ring or a 6-membered ring. Further, in the case of such a nitrogen-containing aromatic polycyclic group having a plurality of nitrogen atoms, the nitrogen-containing compound having a skeleton in which the above formulas (B) and (C) or the above formula (B) and the following formula (D) are combined. Aromatic polycyclic organic compounds are preferred.

  The nitrogen-containing group of the nitrogen-containing aromatic polycyclic organic compound is selected from, for example, nitrogen-containing heterocyclic groups represented by the following formulae.

  In each of the above formulas, R is an aromatic hydrocarbon group or condensed aromatic hydrocarbon group having 6 to 40 carbon atoms, an aromatic heterocyclic group or condensed aromatic heterocyclic group having 3 to 40 carbon atoms, or 1 to 1 carbon atoms. 20 is an alkyl group or an alkoxy group having 1 to 20 carbon atoms, n is an integer of 0 to 5, and when n is an integer of 2 or more, a plurality of R may be the same or different from each other.

Furthermore, preferred specific compounds include nitrogen-containing heterocyclic derivatives represented by the following formula (D1).
HAr-L ¹ -Ar ¹ -Ar ² (D1)
In the formula (D1), HAr is a substituted or unsubstituted nitrogen-containing heterocyclic group having 3 to 40 carbon atoms, and L ¹ is a single bond, substituted or unsubstituted aromatic hydrocarbon having 6 to 40 carbon atoms. A group, a condensed aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group having 3 to 40 carbon atoms or a condensed aromatic heterocyclic group, and Ar ¹ is a substituted or unsubstituted 2 to 6 carbon atom having 2 to 6 carbon atoms. And Ar ² is a substituted or unsubstituted aromatic hydrocarbon group having 6 to 40 carbon atoms, a condensed aromatic hydrocarbon group, or a substituted or unsubstituted aromatic group having 3 to 40 carbon atoms. It is a heterocyclic group or a condensed aromatic heterocyclic group.

HAr is selected from the following group, for example.

L ¹ in the formula (D1) is selected from the following group, for example.

Ar ¹ in the formula (D1) is selected from, for example, arylanthranyl groups of the following formulas (D2) and (D3).

In Formula (D2) and Formula (D3), R ^{1 to} R ¹⁴ are each independently a hydrogen atom, a deuterium atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms, or an alkoxy having 1 to 20 carbon atoms. Group, aryloxy group having 6 to 40 carbon atoms, substituted or unsubstituted aromatic hydrocarbon group or condensed aromatic hydrocarbon group having 6 to 40 carbon atoms, or substituted or unsubstituted aromatic group having 3 to 40 carbon atoms A heterocyclic group or a condensed aromatic heterocyclic group, and Ar ³ is a substituted or unsubstituted aromatic hydrocarbon group having 6 to 40 carbon atoms or a condensed aromatic hydrocarbon group or substituted or unsubstituted carbon atoms having 3 to 3 carbon atoms. 40 aromatic heterocyclic groups or condensed aromatic heterocyclic groups. Further, R ^{1 to} R ⁸ may be nitrogen-containing heterocyclic derivatives each of which is a hydrogen atom or a deuterium atom.

Ar ² in the formula (D1) is selected from the following group, for example.

  In addition to these, the following compounds are also preferably used as the nitrogen-containing aromatic polycyclic organic compound as the electron transfer compound.

In formula (D4), R _{1 to} R ₄ each independently represent a hydrogen atom, a deuterium atom, a substituted or unsubstituted aliphatic group having 1 to 20 carbon atoms, a substituted or unsubstituted carbon number of 3 to 20 An aliphatic cyclic group, a substituted or unsubstituted aromatic ring group having 6 to 50 carbon atoms, a substituted or unsubstituted heterocyclic group having 3 to 50 carbon atoms, and X ₁ and X ₂ are each independently Represents an oxygen atom, a sulfur atom, or a dicyanomethylene group.

In addition, the following compounds are also preferably used as the electron transfer compound.

In the formula (D5), R ¹ , R ² , R ³ and R ⁴ are the same or different groups, and are an aromatic hydrocarbon group or a condensed aromatic hydrocarbon group represented by the following formula (D6). It is.

In the formula (D6), R ⁵ , R ⁶ , R ⁷ , R ⁸ and R ⁹ are the same or different from each other, and are a hydrogen atom, a deuterium atom, a saturated or unsaturated alkoxy group having 1 to 20 carbon atoms. Group, a saturated or unsaturated alkyl group having 1 to 20 carbon atoms, an amino group, or an alkylamino group having 1 to 20 carbon atoms. At least one of R ⁵ , R ⁶ , R ⁷ , R ⁸ and R ⁹ is a group other than a hydrogen atom or a deuterium atom.

  Furthermore, the electron transfer compound may be a polymer compound containing the nitrogen-containing heterocyclic group or the nitrogen-containing heterocyclic derivative.

The electron transport layer of the organic EL device of the present invention particularly preferably contains at least one nitrogen-containing heterocyclic derivative represented by the following formulas (E) to (G).

(In Formula (E) to Formula (G), Z ¹ , Z ^2, and Z ³ are each independently a nitrogen atom or a carbon atom.
R ¹ and R ² are each independently a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 50 ring atoms, substituted or unsubstituted carbon. They are a C1-C20 alkyl group, a substituted or unsubstituted C1-C20 haloalkyl group, or a substituted or unsubstituted C1-C20 alkoxy group.

n is an integer of 0 to 5, and when n is an integer of 2 or more, the plurality of R ¹ may be the same as or different from each other. Further, two adjacent R ¹ may be bonded to each other to form a substituted or unsubstituted hydrocarbon ring.
Ar ¹ is a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms or a substituted or unsubstituted heteroaryl group having 5 to 50 ring atoms.
Ar ² is a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, substituted Alternatively, it is an unsubstituted aryl group having 6 to 50 ring carbon atoms or a substituted or unsubstituted heteroaryl group having 5 to 50 ring atoms.

However, ^one of Ar ¹ and Ar ² is a substituted or unsubstituted condensed aromatic hydrocarbon ring group having 10 to 50 ring carbon atoms or a substituted or unsubstituted condensed aromatic group having 9 to 50 ring atoms. It is a heterocyclic group.
Ar ³ is a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms or a substituted or unsubstituted heteroarylene group having 5 to 50 ring atoms.
L ¹ , L ² and L ³ are each independently a single bond, a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted divalent ring having 9 to 50 ring atoms. A condensed aromatic heterocyclic group. )

Examples of the aryl group having 6 to 50 ring carbon atoms include phenyl, naphthyl, anthryl, phenanthryl, naphthacenyl, chrysenyl, pyrenyl, biphenyl, terphenyl, tolyl, fluoranthenyl, fluorenyl Groups and the like.
Examples of heteroaryl groups having 5 to 50 ring atoms include pyrrolyl, furyl, thienyl, silolyl, pyridyl, quinolyl, isoquinolyl, benzofuryl, imidazolyl, pyrimidyl, carbazolyl, selenophenyl Group, oxadiazolyl group, triazolyl group, pyrazinyl group, pyridazinyl group, triazinyl group, quinoxalinyl group, acridinyl group, imidazo [1,2-a] pyridinyl group, imidazo [1,2-a] pyrimidinyl group and the like.

Examples of the alkyl group having 1 to 20 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group.
Examples of the haloalkyl group having 1 to 20 carbon atoms include groups obtained by substituting one or more hydrogen atoms of the alkyl group with at least one halogen atom selected from fluorine, chlorine, iodine and bromine.
Examples of the alkoxy group having 1 to 20 carbon atoms include groups having the alkyl group as an alkyl moiety.
Examples of the arylene group having 6 to 50 ring carbon atoms include a group obtained by removing one hydrogen atom from the aryl group.
Examples of the divalent condensed aromatic heterocyclic group having 9 to 50 ring atoms include groups obtained by removing one hydrogen atom from the condensed aromatic heterocyclic group described as the heteroaryl group.

Although the film thickness of an electron carrying layer is not specifically limited, Preferably it is 1 nm-100 nm.
Moreover, it is preferable to use an insulator or a semiconductor as an inorganic compound in addition to the nitrogen-containing ring derivative as a component of the electron injection layer that can be provided adjacent to the electron transport layer. If the electron injection layer is made of an insulator or a semiconductor, current leakage can be effectively prevented and the electron injection property can be improved.

As such an insulator, it is preferable to use at least one metal compound selected from the group consisting of alkali metal chalcogenides, alkaline earth metal chalcogenides, alkali metal halides and alkaline earth metal halides. If the electron injection layer is composed of these alkali metal chalcogenides or the like, it is preferable in that the electron injection property can be further improved. Specifically, preferable alkali metal chalcogenides include, for example, Li ₂ O, K ₂ O, Na ₂ S, Na ₂ Se, and Na ₂ O, and preferable alkaline earth metal chalcogenides include, for example, CaO, BaO. , SrO, BeO, BaS and CaSe. Further, preferable alkali metal halides include, for example, LiF, NaF, KF, LiCl, KCl, and NaCl. Examples of preferable alkaline earth metal halides include fluorides such as CaF ₂ , BaF ₂ , SrF ₂ , MgF ₂ and BeF ₂ , and halides other than fluorides.

  Further, as a semiconductor, an oxide, nitride, or oxynitride containing at least one element of Ba, Ca, Sr, Yb, Al, Ga, In, Li, Na, Cd, Mg, Si, Ta, Sb, and Zn. One kind alone or a combination of two or more kinds of products may be mentioned. In addition, the inorganic compound constituting the electron injection layer is preferably a microcrystalline or amorphous insulating thin film. If the electron injection layer is composed of these insulating thin films, a more uniform thin film is formed, and pixel defects such as dark spots can be reduced. Examples of such inorganic compounds include alkali metal chalcogenides, alkaline earth metal chalcogenides, alkali metal halides and alkaline earth metal halides.

  When such an insulator or semiconductor is used, the preferred thickness of the layer is about 0.1 nm to 15 nm. Further, the electron injection layer in the present invention is preferable even if it contains the above-mentioned electron donating dopant.

(Hole transport layer)
An organic layer formed between the light emitting layer and the anode, and has a function of transporting holes from the anode to the light emitting layer. When the hole transport layer is composed of a plurality of layers, an organic layer close to the anode may be defined as a hole injection layer. The hole injection layer has a function of efficiently injecting holes from the anode into the organic layer unit.

As another material for forming the hole transport layer, an aromatic amine compound, for example, an aromatic amine derivative represented by the following formula (H) is preferably used.

In the formula (H), Ar ^{1 to} Ar ⁴ represent a substituted or unsubstituted aromatic hydrocarbon group having 6 to 50 ring carbon atoms or a condensed aromatic hydrocarbon group, a substituted or unsubstituted ring forming atom number of 5 to 5 50 aromatic heterocyclic groups or condensed aromatic heterocyclic groups, or a group in which these aromatic hydrocarbon groups or condensed aromatic hydrocarbon groups and aromatic heterocyclic groups or condensed aromatic heterocyclic groups are bonded.
In the formula (H), L represents a substituted or unsubstituted aromatic hydrocarbon group or condensed aromatic hydrocarbon group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted ring atom number of 5 to 50. Represents an aromatic heterocyclic group or a condensed aromatic heterocyclic group.

Specific examples of the compound of formula (H) are shown below.

An aromatic amine represented by the following formula (J) is also preferably used for forming the hole transport layer.

In the formula (J), the definition of Ar ^{1 to} Ar ^{3 is the same as} the definition of Ar ^{1 to} Ar ^{4 in} the formula (H). Specific examples of the compound of formula (J) are shown below, but are not limited thereto.

The hole transport layer of the organic EL device of the present invention may have a two-layer structure of a first hole transport layer (anode side) and a second hole transport layer (cathode side).
Although the film thickness of a positive hole transport layer is not specifically limited, It is preferable that it is 10-200 nm.

In the organic EL device of the present invention, a layer containing an acceptor material may be bonded to the anode side of the hole transport layer or the first hole transport layer. This is expected to reduce drive voltage and manufacturing costs.
As the acceptor material, a compound represented by the following formula (K) is preferable.

(In the above formula (K), R _{21 to} R ₂₆ may be the same as or different from each other, and each independently represents a cyano group, —CONH ₂ , a carboxyl group, or —COOR ₂₇ (R ₂₇ has 1 to 20 carbon atoms). Represents an alkyl group or a cycloalkyl group having 3 to 20 carbon atoms, provided that one or two or more pairs of R ₂₁ and R ₂₂ , R ₂₃ and R ₂₄ , and R ₂₅ and R ₂₆ are combined. A group represented by -CO-O-CO- may be formed.)
Examples of R ₂₇ include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a t-butyl group, a cyclopentyl group, and a cyclohexyl group.
The thickness of the layer containing the acceptor material is not particularly limited, but is preferably 5 to 20 nm.

(N / p doping)
In the hole transport layer and the electron transport layer described above, as described in Japanese Patent No. 3695714, the carrier injection ability is improved by doping the donor material (n) and acceptor material (p). Can be adjusted.
A typical example of n doping is a method of doping a metal such as Li or Cs into an electron transport material, and a typical example of p doping is F ₄ TCNQ (2, 3, 5, 6) as a hole transport material. -Tetrafluor-7,7,8,8-tetracyanoquinodimethane) and the like may be used.

(Space layer)
For example, when the fluorescent layer and the phosphorescent layer are laminated, the space layer is a fluorescent layer for the purpose of adjusting the carrier balance so that excitons generated in the phosphorescent layer are not diffused into the fluorescent layer. It is a layer provided between the layer and the phosphorescent light emitting layer. In addition, the space layer can be provided between the plurality of phosphorescent light emitting layers.
Since the space layer is provided between the light emitting layers, a material having both electron transport properties and hole transport properties is preferable. In order to prevent diffusion of triplet energy in the adjacent phosphorescent light emitting layer, the triplet energy is preferably 2.6 eV or more. Examples of the material used for the space layer include the same materials as those used for the above-described hole transport layer.

(Barrier layer)
The organic EL device of the present invention preferably has a barrier layer such as an electron barrier layer, a hole barrier layer, or a triplet barrier layer in a portion adjacent to the light emitting layer. Here, the electron barrier layer is a layer that prevents electrons from leaking from the light emitting layer to the hole transport layer, and the hole barrier layer is a layer that prevents holes from leaking from the light emitting layer to the electron transport layer. is there.
The triplet barrier layer prevents the triplet excitons generated in the light emitting layer from diffusing into the surrounding layers, and confins the triplet excitons in the light emitting layer, thereby transporting electrons other than the light emitting dopant of the triplet excitons. It has a function of suppressing energy deactivation on the molecules of the layer.

In the case where a triplet barrier layer is provided, in the phosphorescent device, if the triplet energy of the phosphorescent dopant in the light emitting layer is E ^T _d and the triplet energy of the compound used as the triplet barrier layer is E ^T _TB , E ^T _d < If the energy magnitude relationship of E ^T _TB is satisfied, the triplet exciton of the phosphorescent dopant is confined (cannot move to other molecules) and the energy deactivation path other than light emission on the dopant is interrupted. It is assumed that light can be emitted with high efficiency. However, even if the relationship of E ^T _d <E ^T _TB is satisfied, if this energy difference ΔE ^T = E ^T _TB −E ^T _d is small, under the environment of room temperature, which is the actual element driving environment, , endothermically triplet excitons overcame this energy difference Delta] E ^T by thermal energy near is considered to be possible to move to another molecule. In particular, in the case of phosphorescence emission, the exciton lifetime is longer than that of fluorescence emission, so that the influence of the endothermic exciton transfer process is likely to appear. The energy difference ΔE ^T is preferably as large as possible relative to the thermal energy at room temperature, more preferably 0.1 eV or more, and particularly preferably 0.2 eV or more. On the other hand, in the fluorescent element, the organic EL element material of the present invention can be used as a triplet barrier layer having a TTF element structure described in International Publication WO2010 / 134350A1.

Further, the electron mobility of the material constituting the triplet barrier layer is desirably 10 ⁻⁶ cm ² / Vs or more in the range of the electric field strength of 0.04 to 0.5 MV / cm. As a method for measuring the electron mobility of an organic material, several methods such as the Time of Flight method are known. Here, the electron mobility is determined by impedance spectroscopy.
The electron injection layer is desirably 10 ⁻⁶ cm ² / Vs or more in the range of electric field strength of 0.04 to 0.5 MV / cm. This facilitates the injection of electrons from the cathode into the electron transport layer, and also promotes the injection of electrons into the adjacent barrier layer and the light emitting layer, thereby enabling driving at a lower voltage.

Hereinafter, the present invention will be described in more detail based on synthesis examples and examples.
[Synthesis of Intermediate Compound]
The following intermediates 1 to 5 were synthesized.

-Synthesis | combination of intermediate body 1 and 2 It synthesize | combined with reference to the patent 4388590 description.

Synthesis of Intermediate 3 Under a stream of argon, 100 g of 2,4,6-trichloropyrimidine, 66.4 g of phenylboronic acid, tetrakis (triphenylphosphine) palladium (0) [Pd (PPhe ₃ ) in a 5 L reaction vessel ₄ ] was added, 1.7 L of toluene, 66.4 g of Na ₂ CO ₃ and 800 ml of distilled water were added, and the mixture was stirred at 50 ° C. for 20 hours.
The reaction solution was extracted with toluene / water and dried over anhydrous sodium sulfate. This was concentrated under reduced pressure, and the resulting crude product was subjected to column purification to obtain 53.5 g of white powder.

Synthesis of Intermediate 4 Under a stream of argon, 50 g of Intermediate 3, 32.6 g of 4-cyanophenylboronic acid, 5.13 g of Pd (PPhe ₃ ) ₄ , 830 mL of dimethoxyethane, Na _{2 in} a 3 L reaction vessel 70.6 g of CO ₃ and 340 ml of distilled water were added and stirred at 50 ° C. for 62 hours.
After 600 mL of water was added to the reaction solution to precipitate crystals, the precipitated crystals were filtered. After dissolving with 500 mL of toluene, it was filtered. The solution was concentrated and recrystallized with toluene three times to obtain 30.4 g of white powder.

-Synthesis | combination of the intermediate body 42.5g white powder was obtained by making it react similarly in the synthesis example 4 except using 3-cyanophenyl boronic acid instead of 4-cyanophenyl boronic acid.

[Synthesis of materials for organic EL elements]
Synthesis Example 1 (Synthesis of Compound H-1)
The following compound H-1 was synthesized.

Under an argon stream, Intermediate 2 (5.1 g), Intermediate 4 (5.8 g), t-butoxy sodium 2.6 g (manufactured by Hiroshima Wako), Tris (dibenzylideneacetone) dipalladium (0) 540 mg
(Manufactured by Aldrich), 340 mg of tri-t-butylphosphonium tetrafluoroborate and 100 mL of dehydrated xylene were added and reacted at reflux for 8 hours.
After cooling, 500 mL of water was added, the mixture was filtered through Celite, and the filtrate was extracted with toluene and dried over anhydrous magnesium sulfate. This was concentrated under reduced pressure, and the resulting crude product was purified by column, recrystallized from toluene, collected by filtration and dried to obtain 4.8 g of a pale yellow powder.
Analysis of FD-MS (field desorption mass spectrum) was 588 (M + 1), and the glass transition temperature (Tg) was 150 ° C.

Synthesis Example 2 (Synthesis of Compound H-2)
The following compound H-2 was synthesized.

In Synthesis Example 1, the reaction was performed in the same manner except that Intermediate 5 was used instead of Intermediate 4. As a result, 4.2 g of a pale yellow powder was obtained.
Analysis of FD-MS was 588 (M + 1), and the glass transition temperature (Tg) was 134 ° C.

[Production of organic EL element and evaluation of light emission performance]
Example 1
(Manufacture of organic EL elements)
A glass substrate with an ITO transparent electrode of 25 mm × 75 mm × thickness 1.1 mm (manufactured by Geomatic Co., Ltd.) was subjected to ultrasonic cleaning in isopropyl alcohol for 5 minutes and then UV ozone cleaning for 30 minutes.
The glass substrate with the transparent electrode line after washing is mounted on the substrate holder of the vacuum deposition apparatus, and the following electron-accepting (acceptor) compound is first formed so as to cover the transparent electrode on the surface on which the transparent electrode line is formed. HI-1 was vapor-deposited to form a compound HI-1 film having a thickness of 5 nm.
On this compound HI-1 film | membrane, the following aromatic amine derivative (compound HT-1) was vapor-deposited as a 1st positive hole transport material, and the 40-nm-thick 1st positive hole transport layer was formed into a film. Following the film formation of the first hole transport layer, the following aromatic amine derivative (Compound HT-2) was deposited as a second hole transport material to form a second hole transport layer having a thickness of 10 nm.

Further, on this second hole transport layer, the compound H-1 synthesized in Synthesis Example 1 as a host material and the following compound PQIr (acac) as a phosphorescent material are co-evaporated to form a phosphorescent layer having a thickness of 40 nm. Was deposited. The concentration of the compound PQIr (acac) in the light emitting layer was 8.0% by mass. This co-deposited film functions as a light emitting layer.
Then, following this light emitting layer film formation, the following compound ET-1 was formed in a film thickness of 40 nm. This compound ET-1 film functions as an electron transport layer.
Next, LiF was used as an electron injecting electrode (cathode) and the film thickness was set to 1 nm at a film forming rate of 0.1 angstrom / min. Metal Al was vapor-deposited on this LiF film, and a metal cathode was formed with a film thickness of 80 nm to produce an organic EL device.

The obtained organic EL device was evaluated for 80% life (time until the luminance decreased to 80% of the initial light emission luminance) when driven at a constant current with an initial light emission luminance of 10,000 cd / m ² . The results are shown in Table 1.

Example 2
An organic EL device was prepared and evaluated in the same manner as in Example 1 except that Compound H-2 synthesized in Synthesis Example 2 was used instead of Compound H-1 as the host material for the light emitting layer. The results are shown in Table 1.

Comparative Example 1
An organic EL device was prepared and evaluated in the same manner as in Example 1 except that the following compound F-1 was used instead of the compound H-1 as a host material for the light emitting layer. The results are shown in Table 1.

Example 3
An organic EL device was prepared and evaluated in the same manner as in Example 1 except that the following compound Ir (tpiq) 2 (acac) was used instead of the compound PQIr (acac) as the phosphorescent material of the light emitting layer. The results are shown in Table 1.

Example 4
An organic EL device was prepared and evaluated in the same manner as in Example 3 except that Compound H-2 synthesized in Synthesis Example 2 was used as the host material for the light-emitting layer instead of Compound H-1. The results are shown in Table 1.

Comparative Example 2
An organic EL device was prepared and evaluated in the same manner as in Example 3 except that the following compound F-1 was used instead of the compound H-1 as the host material for the light emitting layer. The results are shown in Table 1.

  The material for an organic EL element of the present invention is useful as a material for realizing a phosphorescent organic EL element having a long lifetime.

DESCRIPTION OF SYMBOLS 1 Organic EL element 2 Substrate 3 Anode 4 Cathode 5 Light emitting layer 6 Hole injection / transport layer 7 Electron injection / transport layer 10 Light emitting unit

Claims (21)

The material for organic electroluminescent elements represented by either of following formula (1)-(6).

[In the formula (I),
A 1 , A 2 , B 1 , B 2 and C are each independently a single bond, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted ring forming atom. The heterocyclic group of several 5-30 is represented.
Y 1 to Y 10 each independently represent N (nitrogen atom) or CR a (C is a carbon atom). However, among the Y 1 to Y 10, when two adjacent is a CR a, it may be bonded to each other part of the R a in adjacent CR a to form a ring structure.
Each R a independently represents a hydrogen atom, a halogen atom, a cyano group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted group; A haloalkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted haloalkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted silyl group, a substituted or unsubstituted dialkylamino group having 2 to 20 carbon atoms, substituted or unsubstituted A substituted or unsubstituted diarylamino group having 12 to 30 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon ring group having 6 to 30 carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 30 ring atoms; The plurality of R a may be the same as or different from each other.
sa and ta each independently represents an integer of 0 to 5, sb and tb each represents an integer of 0 to 4, u represents an integer of 0 to 2, and sa + sb + ta + tb + u is an integer of 1 to 5. .
If sa is 1 to 5, A 1 and (Q 1) Q 1 of sa is attached. When sb is 1 to 4 , at least one of Y 1 to Y 4 is bonded to B 1 of (B 1 -Q 1 ) sb .
If ta is 1 to 5, Q 2 and A 2 (Q 2) ta is attached. If tb is 1 to 4, at least one (B 2 -Q 2) B 2 of tb of Y 5 to Y 8 are attached.
When u is 1 to 2, at least one of Y 9 and Y 10 and C of (CQ 3 ) u are bonded.
Q 1 , Q 2 and Q 3 each independently represent -Az-W q .
q represents the integer of 1-4.
If Q 1 is are multiple, multiple Q 1 is may be the same or different from each other. If Q 2 there is a plurality, the plurality of Q 2 is may be the same or different from each other. If Q 3 is plural, Q 3 are may be the same or different from each other.
Az is a (q + 1) -valent group of a ring represented by the following formula (X).

(In the formula ^(X), Z 1 ~Z ⁵ each independently represent a nitrogen atom or a CR ^b.
In the CR ^{b, R b} are as defined above ^{R a.} However, when two adjacent Z ^{1 to} Z ⁵ are CR ^b , a part of R ^b in adjacent CR ^b may be bonded to form a ring structure.
If the R ^b there are a plurality, a plurality of R ^b may be the same or different from each other. )
When there are a plurality of Az, the plurality of Az may be the same as or different from each other.
W represents a substituent X, an aromatic hydrocarbon group having 6 to 30 ring carbon atoms substituted with the substituent X, or a heterocyclic group having 5 to 30 ring atoms substituted with the substituent X. However, the aromatic hydrocarbon group having 6 to 30 ring carbon atoms substituted with the substituent X and the heterocyclic group having 5 to 30 ring atoms substituted with the substituent X are substituents other than the substituent X. You may have. The substituent X is an electron withdrawing group. When there are a plurality of Ws, the plurality of Ws may be the same as or different from each other. ] The material for organic electroluminescent elements represented by either of following formula (1)-(6).

[In the formula (I),
A 1 , A 2 , B 1 , B 2 and C are each independently a single bond, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted ring forming atom. The heterocyclic group of several 5-30 is represented.
Y 1 to Y 10 each independently represent N (nitrogen atom) or CR a (C is a carbon atom). However, among the Y 1 to Y 10, when two adjacent is a CR a, it may be bonded to each other part of the R a in adjacent CR a to form a ring structure.
Each R a independently represents a hydrogen atom, a halogen atom, a cyano group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted group; A haloalkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted haloalkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted silyl group, a substituted or unsubstituted dialkylamino group having 2 to 20 carbon atoms, substituted or unsubstituted A substituted or unsubstituted diarylamino group having 12 to 30 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon ring group having 6 to 30 carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 30 ring atoms; The plurality of R a may be the same as or different from each other.
sa and ta each independently represents an integer of 0 to 5, sb and tb each represents an integer of 0 to 4, u represents an integer of 0 to 2, and sa + sb + ta + tb + u is an integer of 1 to 5. .
If sa is 1 to 5, A 1 and (Q 1) Q 1 of sa is attached. When sb is 1 to 4 , at least one of Y 1 to Y 4 is bonded to B 1 of (B 1 -Q 1 ) sb .
If ta is 1 to 5, Q 2 and A 2 (Q 2) ta is attached. If tb is 1 to 4, at least one (B 2 -Q 2) B 2 of tb of Y 5 to Y 8 are attached.
When u is 1 to 2, at least one of Y 9 and Y 10 and C of (CQ 3 ) u are bonded.
Q 1 , Q 2 and Q 3 each independently represent -Az-W q .
q represents the integer of 1-4.
If Q 1 is are multiple, multiple Q 1 is may be the same or different from each other. If Q 2 there is a plurality, the plurality of Q 2 is may be the same or different from each other. If Q 3 is plural, Q 3 are may be the same or different from each other.
Az is a (q + 1) -valent group of a ring represented by the following formula (X).

(In the formula ^(X), Z 1 ~Z ⁵ each independently represent a nitrogen atom or a CR ^b.
In the CR ^{b, R b} are as defined above ^{R a.} However, when two adjacent Z ^{1 to} Z ⁵ are CR ^b , a part of R ^b in adjacent CR ^b may be bonded to form a ring structure.
If the R ^b there are a plurality, a plurality of R ^b may be the same or different from each other. )
When there are a plurality of Az, the plurality of Az may be the same as or different from each other.
W represents a substituent X, an aromatic hydrocarbon group having 6 to 30 ring carbon atoms substituted with the substituent X, or a heterocyclic group having 5 to 30 ring atoms substituted with the substituent X. However, the aromatic hydrocarbon group having 6 to 30 ring carbon atoms substituted with the substituent X and the heterocyclic group having 5 to 30 ring atoms substituted with the substituent X are substituents other than the substituent X. You may have. The substituent X is a group whose Hammett's rule constant (σp (para)) takes a positive value. When there are a plurality of Ws, the plurality of Ws may be the same as or different from each other. ] The material for organic electroluminescent elements represented by either of following formula (1)-(6).

[In the formula (I),
A 1 , A 2 , B 1 , B 2 and C are each independently a single bond, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted ring forming atom. The heterocyclic group of several 5-30 is represented.
Y 1 to Y 10 each independently represent N (nitrogen atom) or CR a (C is a carbon atom). However, among the Y 1 to Y 10, when two adjacent is a CR a, it may be bonded to each other part of the R a in adjacent CR a to form a ring structure.
Each R a independently represents a hydrogen atom, a halogen atom, a cyano group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted group; A haloalkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted haloalkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted silyl group, a substituted or unsubstituted dialkylamino group having 2 to 20 carbon atoms, substituted or unsubstituted A substituted or unsubstituted diarylamino group having 12 to 30 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon ring group having 6 to 30 carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 30 ring atoms; The plurality of R a may be the same as or different from each other.
sa and ta each independently represents an integer of 0 to 5, sb and tb each represents an integer of 0 to 4, u represents an integer of 0 to 2, and sa + sb + ta + tb + u is an integer of 1 to 5. .
If sa is 1 to 5, A 1 and (Q 1) Q 1 of sa is attached. When sb is 1 to 4 , at least one of Y 1 to Y 4 is bonded to B 1 of (B 1 -Q 1 ) sb .
If ta is 1 to 5, Q 2 and A 2 (Q 2) ta is attached. If tb is 1 to 4, at least one (B 2 -Q 2) B 2 of tb of Y 5 to Y 8 are attached.
When u is 1 to 2, at least one of Y 9 and Y 10 and C of (CQ 3 ) u are bonded.
Q 1 , Q 2 and Q 3 each independently represent -Az-W q .
q represents the integer of 1-4.
If Q 1 is are multiple, multiple Q 1 is may be the same or different from each other. If Q 2 there is a plurality, the plurality of Q 2 is may be the same or different from each other. If Q 3 is plural, Q 3 are may be the same or different from each other.
Az is a (q + 1) -valent group of a ring represented by the following formula (X).

(In the formula ^(X), Z 1 ~Z ⁵ each independently represent a nitrogen atom or a CR ^b.
In the CR ^{b, R b} are as defined above ^{R a.} However, when two adjacent Z ^{1 to} Z ⁵ are CR ^b , a part of R ^b in adjacent CR ^b may be bonded to form a ring structure.
If the R ^b there are a plurality, a plurality of R ^b may be the same or different from each other. )
When there are a plurality of Az, the plurality of Az may be the same as or different from each other.
W represents a substituent X, an aromatic hydrocarbon group having 6 to 30 ring carbon atoms substituted with the substituent X, or a heterocyclic group having 5 to 30 ring atoms substituted with the substituent X. However, the aromatic hydrocarbon group having 6 to 30 ring carbon atoms substituted with the substituent X and the heterocyclic group having 5 to 30 ring atoms substituted with the substituent X are substituents other than the substituent X. You may have. The substituent X is an electron withdrawing group in which the Hammett's rule substituent constant (σp (para)) takes a positive value. When there are a plurality of Ws, the plurality of Ws may be the same as or different from each other. ] The material for organic electroluminescent elements according to any one of claims 1 to 3, which is represented by any one of the following formulas (1-1) to (6-1).

[In the formulas (1-1) to (6-1),
A ¹ , A ² , Y ^{1 to} Y ¹⁰ , Q ¹ and Q ² each represent the same group as in the above formulas (1) to (6). sa and ta each independently represent an integer of 0 to 5, and sa + ta is an integer of 1 to 5. ]   Az is a condensed or polycyclic group containing a substituted or unsubstituted nitrogen-containing 6-membered ring having 1 to 3 nitrogen atoms or a substituted or unsubstituted nitrogen-containing 6-membered ring having 1 to 3 nitrogen atoms. Item 5. The organic electroluminescent element material according to any one of Items 1 to 4.   The Az is a condensed polycyclic group containing a substituted or unsubstituted nitrogen-containing 6-membered ring having 1 or 2 nitrogen atoms, or a substituted or unsubstituted nitrogen-containing 6-membered ring having 1 or 2 nitrogen atoms. Item 6. The organic electroluminescent element material according to any one of Items 1 to 5.   The Az is a ring group selected from the group consisting of a substituted or unsubstituted pyrimidine ring, a substituted or unsubstituted pyridine ring, a substituted or unsubstituted quinazoline ring, and a substituted or unsubstituted quinoline ring. The organic electroluminescent element material in any one of 1-6.   The organic electroluminescent element material according to claim 1, wherein Az is a ring group selected from a substituted or unsubstituted pyrimidine ring and a substituted or unsubstituted pyridine ring.   Said sa and ta are 0 or 1, respectively, The organic electroluminescent element material in any one of Claims 1-8.   Said ta is 0, The organic electroluminescent element material in any one of Claims 1-9.   The organic electroluminescent element material according to claim 1, wherein the sa + sb + ta + tb + u is 1. 5. The sa is 1, the ta is 0, and the A ² is a substituted or unsubstituted aromatic hydrocarbon ring group having 6 to 30 ring carbon atoms or a substituted or unsubstituted ring forming atom number of 5 to 5. The organic electroluminescent element material according to any one of claims 1 to 11, which is 30 heterocyclic groups. Wherein sa is 1, wherein A ¹ is a single bond, an organic electroluminescence device material according to any one of claims 1 to 12. The substituent X is selected from the group consisting of —CN, —F, —Cl, —Br, —I, —CO ₂ R ^C , —COR ^C , —CF ₃ , —SO ₂ R ^C , —NO _2. The material for organic electroluminescence elements according to claim 1. (R ^C are each independently a hydrogen atom, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, a substituted or unsubstituted ring atoms 5 to 30 heterocyclic group, or a substituted Alternatively, it represents an unsubstituted alkyl group having 1 to 30 carbon atoms.) The substituent X ^{_{is, -CN, -F, -CF 3,}} -CO 2 R C, -COR C, -SO 2 R C, is selected from the group consisting of, according to any of claims 1 to 14 Material for organic electroluminescence element.
(R ^C are each independently a hydrogen atom, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, a substituted or unsubstituted ring atoms 5 to 30 heterocyclic group, or a substituted Alternatively, it represents an unsubstituted alkyl group having 1 to 30 carbon atoms.)   The organic electroluminescent element material according to claim 1, wherein the substituent X is —CN or —F.   The organic electroluminescent element material according to any one of claims 1 to 16, wherein the substituent X is -CN.   W is a CN-substituted phenyl group, a CN-substituted biphenyl group, a CN-substituted naphthyl group, a CN-substituted diphenylfluorenyl group, a CN-substituted spirobifluorenyl group, a CN-substituted dimethylfluorenyl group, a CN-substituted phenanthrenyl group, CN The organic electroluminescent element material according to claim 1, which is a substituted triphenylenyl group, a CN-substituted dibenzofuranyl group, or a CN-substituted dibenzothiophenyl group.   It has one or more organic thin film layers containing a light emitting layer between a cathode and an anode, and at least 1 layer of the said organic thin film layer contains the material for organic electroluminescent elements in any one of Claims 1-18 Organic electroluminescence device.   The organic electroluminescent element according to claim 19, wherein the light emitting layer contains the material for an organic electroluminescent element. The said light emitting layer contains a phosphorescent material, and the said phosphorescent material is an ortho metalated complex of the metal atom selected from iridium (Ir), osmium (Os), and platinum (Pt). Organic electroluminescence element.

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