JP2020141120A - Light-emitting element - Google Patents

Abstract

To provide a light-emitting element superior in light emission efficiency.SOLUTION: A light-emitting element comprises: a negative electrode; a first organic layer containing a compound having a crosslinking group and a phosphorescent transition metal complex; a second organic layer containing a crosslinked body of a compound which is the same as the compound having a crosslinking group; and a positive electrode in this order. In the first organic layer, the proportion of the compound having a crosslinking group is 2-10 mass% to a total mass of the first organic layer. The compound having a crosslinking group may be at least one compound having a crosslinking group, which is selected from a group consisting of crosslinking groups represented by the formulas (XL-1) to (XL-19).SELECTED DRAWING: Figure 1

Description

The present invention relates to a light emitting device.

Light emitting devices such as organic electroluminescence devices can be suitably used for display and lighting applications, and have been actively developed in recent years. As the light emitting device, for example, a light emitting device having a hole transport layer containing a crosslinked body of a polymer compound having a crosslinking group and a light emitting layer containing a host material and an iridium complex is known (Patent Document). 1).

Japanese Unexamined Patent Publication No. 2011-105701

However, the luminous efficiency of the light emitting element is not always sufficient.
Therefore, an object of the present invention is to provide a light emitting element having excellent luminous efficiency.

［式（ＸＬ−１）〜式（ＸＬ−１９）中、Ｒ^XLは、メチレン基、酸素原子又は硫黄原子を表し、ｎ^XLは、０〜５の整数を表す。Ｒ^XLが複数存在する場合、それらは同一でも異なっていてもよい。ｎ^XLが複数存在する場合、それらは同一でも異なっていてもよい。
＊１は結合位置を表す。
これらの架橋基は置換基を有していてもよく、前記置換基が複数存在する場合、複数の置換基が互いに結合して、それぞれが結合する炭素原子とともに環を形成していてもよい。］
［３］前記架橋基を有する化合物が、式（１）又は式（１'）で表される構成単位を有する高分子化合物である、［２］に記載の発光素子。

［式（１）中、ｎＡは０〜５の整数を表し、ｎは１又は２を表す。ｎＡが複数存在する場合、それらは同一でも異なっていてもよい。
Ａｒ³は、芳香族炭化水素基又は複素環基を表し、これらの基は置換基を有していてもよい。
Ｌ^Aは、アルキレン基、シクロアルキレン基、アリーレン基、２価の複素環基、−ＮＲ’−で表される基、酸素原子又は硫黄原子を表し、酸素原子及び硫黄原子以外のこれらの基は置換基を有していてもよい。Ｒ’は、水素原子、アルキル基、シクロアルキル基、アリール基又は１価の複素環基を表し、水素原子以外のこれらの基は置換基を有していてもよい。Ｌ^Aが複数存在する場合、それらは同一でも異なっていてもよい。
Ｘは、前記架橋基群から選ばれる架橋基を表す。Ｘが複数存在する場合、それらは同一でも異なっていてもよい。］

［式（１’）中、ｍＡは０〜５の整数を表し、ｍは１〜４の整数を表し、ｃは０又は１の整数を表す。ｍＡが複数存在する場合、それらは同一でも異なっていてもよい。
Ａｒ⁵は、芳香族炭化水素基、複素環基、又は、芳香族炭化水素環と複素環とが直接結合した基を表し、これらの基は置換基を有していてもよい。
Ａｒ⁴及びＡｒ⁶は、それぞれ独立に、アリーレン基又は２価の複素環基を表し、これらの基は置換基を有していてもよい。
Ａｒ⁴、Ａｒ⁵及びＡｒ⁶はそれぞれ、前記基が結合している窒素原子に結合している前記基以外の基と、直接又は酸素原子もしくは硫黄原子を介して結合して、環を形成していてもよい。
Ｋ^Aは、アルキレン基、シクロアルキレン基、アリーレン基、２価の複素環基、−ＮＲ’’−で表される基、酸素原子又は硫黄原子を表し、酸素原子及び硫黄原子以外のこれらの基は置換基を有していてもよい。Ｒ’’は、水素原子、アルキル基、シクロアルキル基、アリール基又は１価の複素環基を表し、水素原子以外のこれらの基は置換基を有していてもよい。Ｋ^Aが複数存在する場合、それらは同一でも異なっていてもよい。
Ｘ’は、前記架橋基群から選ばれる架橋基、水素原子、アルキル基、シクロアルキル基、アリール基又は１価の複素環基を表し、水素原子以外のこれらの基は置換基を有していてもよい。但し、少なくとも１つのＸ’は、前記架橋基群から選ばれる架橋基である。］
［４］前記燐光発光性遷移金属錯体が、式（１−Ａ）で表される金属錯体である、［１］〜［３］のいずれかに記載の発光素子。

［式（１−Ａ）中、Ｍは、ルテニウム原子、ロジウム原子、パラジウム原子、イリジウム原子又は白金原子を表す。
ｎ¹は１以上の整数を表し、ｎ²は０以上の整数を表す。但し、Ｍがルテニウム原子、ロジウム原子又はイリジウム原子の場合、ｎ¹＋ｎ²は３であり、Ｍがパラジウム原子又は白金原子の場合、ｎ¹＋ｎ²は２である。
Ｅ¹は、炭素原子又は窒素原子を表す。Ｅ¹が複数存在する場合、それらは同一でも異なっていてもよい。
環Ｌ^1Aは、ピリジン環、ジアザベンゼン環、アザナフタレン環、ジアザナフタレン環、トリアゾール環又はジアゾール環を表し、これらの環は置換基を有していてもよい。前記置換基が複数存在する場合、複数の置換基が互いに結合して、それぞれが結合する原子とともに環を形成していてもよい。環Ｌ^1Aが複数存在する場合、それらは同一でも異なっていてもよい。
Ｅ^21A、Ｅ^22A、Ｅ^23A及びＥ^24Aは、それぞれ独立に、窒素原子又は炭素原子を表す。但し、環Ｌ^2Aは、ベンゼン環、ピリジン環又はジアザベンゼン環を表す。Ｅ^21Aが窒素原子の場合、Ｒ^21Aは存在しない。Ｅ^22Aが窒素原子の場合、Ｒ^22Aは存在しない。Ｅ^23Aが窒素原子の場合、Ｒ^23Aは存在しない。Ｅ^24Aが窒素原子の場合、Ｒ^24Aは存在しない。Ｅ^21A、Ｅ^22A、Ｅ^23A及びＥ^24Aは、複数存在する場合、それらはそれぞれ同一でも異なっていてもよい。
Ｒ^21A、Ｒ^22A、Ｒ^23A及びＲ^24Aは、それぞれ独立に、水素原子、アルキル基、シクロアルキル基、アルコキシ基、シクロアルコキシ基、アリール基、アリールオキシ基、１価の複素環基、置換アミノ基又はハロゲン原子を表し、水素原子以外のこれらの基は置換基を有していてもよい。Ｒ^21A、Ｒ^22A、Ｒ^23A及びＲ^24Aが複数存在する場合、それらはそれぞれ同一でも異なっていてもよい。Ｒ^21AとＲ^22A、Ｒ^22AとＲ^23A、Ｒ^23AとＲ^24A、及び、環Ｌ^1Aが有していてもよい置換基とＲ^21Aは、それぞれ結合して、環を形成していてもよい。
Ａ¹−Ｇ¹−Ａ²は、アニオン性の２座配位子を表す。Ａ¹及びＡ²は、それぞれ独立に、炭素原子、酸素原子又は窒素原子を表し、これらの原子は環を構成する原子であってもよい。Ｇ¹は、単結合、又は、Ａ¹及びＡ²とともに２座配位子を構成する原子団を表す。Ａ¹−Ｇ¹−Ａ²が複数存在する場合、それらは同一でも異なっていてもよい。］
［５］前記式（１−Ａ）で表される金属錯体が、式（１−Ｂ１）、式（１−Ｂ２）、式（１−Ｂ３）、式（１−Ｂ４）又は式（１−Ｂ５）で表される金属錯体である、［４］に記載の発光素子。

［式（１−Ｂ１）〜式（１〜Ｂ５）中、Ｍ、ｎ¹、ｎ²、Ｒ^21A、Ｒ^22A、Ｒ^23A、Ｒ^24A及びＡ¹−Ｇ¹−Ａ²は、前記と同じ意味を表す。
ｎ¹¹及びｎ¹²は、それぞれ独立に、１又は２を表す。但し、Ｍがルテニウム原子、ロジウム原子又はイリジウム原子の場合、ｎ¹¹＋ｎ¹²は３であり、Ｍがパラジウム原子又は白金原子の場合、ｎ¹¹＋ｎ¹²は２である。
Ｒ^11B、Ｒ^12B、Ｒ^13B、Ｒ^14B、Ｒ^15B、Ｒ^16B、Ｒ^17B及びＲ^18Bは、それぞれ独立に、水素原子、アルキル基、シクロアルキル基、アルコキシ基、シクロアルコキシ基、アリール基、アリールオキシ基、１価の複素環基、置換アミノ基又はハロゲン原子を表し、水素原子以外のこれらの基は置換基を有していてもよい。Ｒ^11B、Ｒ^12B、Ｒ^13B、Ｒ^14B、Ｒ^15B、Ｒ^16B、Ｒ^17B及びＲ^18Bが複数存在する場合、それらはそれぞれ同一でも異なっていてもよい。
式（１−Ｂ１）中、Ｒ^11BとＲ^12B、Ｒ^12BとＲ^13B、Ｒ^13BとＲ^14B、及び、Ｒ^11BとＲ^21Aは、それぞれ結合して、環を形成していてもよい。
式（１−Ｂ２）中、Ｒ^13BとＲ^14B、Ｒ^13BとＲ^15B、Ｒ^15BとＲ^16B、Ｒ^16BとＲ^17B、Ｒ^17BとＲ^18B、及び、Ｒ^18BとＲ^21Aは、それぞれ結合して、環を形成していてもよい。
式（１−Ｂ３）中、Ｒ^11BとＲ^12B、Ｒ^12BとＲ^13B、Ｒ^13BとＲ^14B、Ｒ^11BとＲ^21A、Ｒ^13BとＲ^15B、Ｒ^15BとＲ^16B、Ｒ^16BとＲ^17B、Ｒ^17BとＲ^18B、及び、Ｒ^18BとＲ^21Aは、それぞれ結合して、環を形成していてもよい。
式（１−Ｂ４）中、Ｒ^11BとＲ^18B、Ｒ^14BとＲ^15B、Ｒ^15BとＲ^16B、Ｒ^16BとＲ^17B、Ｒ^17BとＲ^18B、及び、Ｒ^11BとＲ^21Aは、それぞれ結合して、環を形成していてもよい。
式（１−Ｂ５）中、Ｒ^11BとＲ^12B、Ｒ^12BとＲ^18B、Ｒ^15BとＲ^16B、Ｒ^16BとＲ^17B、Ｒ^17BとＲ^18B、及び、Ｒ^11BとＲ^21Aは、それぞれ結合して、環を形成していてもよい。］
［６］前記第１の有機層と前記第２の有機層とが接する［１］〜［５］のいずれかに記載の発光素子。
［７］陰極、架橋基を有する化合物と燐光発光性遷移金属錯体とを含有する第１の有機層、前記架橋基を有する化合物と同一の化合物の架橋体を含有する第２の有機層、及び陽極をこの順番に有し、前記第１の有機層に含有される前記架橋基を有する化合物の割合が、前記第１の有機層の全質量に対して２〜１０質量％である、発光素子の製造方法であって、前記第１の有機層及び前記第２の有機層を塗布法により形成する、発光素子の製造方法。 The present invention provides the following [1] to [7].
[1] A cathode, a first organic layer containing a compound having a cross-linking group and a phosphorescent transition metal complex, a second organic layer containing a cross-linked product of the same compound as the compound having the cross-linking group, and A light emitting element having an anode in this order and having a compound having a cross-linking group contained in the first organic layer in an amount of 2 to 10% by mass based on the total mass of the first organic layer. ..
[2] The luminescence according to [1], wherein the compound having a cross-linking group is a compound having at least one cross-linking group selected from the group of cross-linking groups represented by the formulas (XL-1) to (XL-19). element.

[In formulas (XL-1) to (XL-19), R ^XL represents a methylene group, an oxygen atom or a sulfur atom, and n ^XL represents an integer of 0 to 5. If there are multiple R ^XLs , they may be the same or different. If there are multiple n ^XLs , they may be the same or different.
* 1 represents the bonding position.
These cross-linking groups may have substituents, and when a plurality of the substituents are present, the plurality of substituents may be bonded to each other to form a ring together with the carbon atom to which each of the cross-linking groups is bonded. ]
[3] The light emitting device according to [2], wherein the compound having a cross-linking group is a polymer compound having a structural unit represented by the formula (1) or the formula (1').

[In equation (1), nA represents an integer from 0 to 5, and n represents 1 or 2. When there are a plurality of nA, they may be the same or different.
Ar ³ represents an aromatic hydrocarbon group or a heterocyclic group, and these groups may have a substituent.
L ^A is an alkylene group, a cycloalkylene group, an arylene group, a divalent heterocyclic group, the group represented by -NR'-, an oxygen atom or a sulfur atom, these groups other than oxygen and sulfur atoms It may have a substituent. R'represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, and these groups other than the hydrogen atom may have a substituent. If L ^A is plurally present, they may be the same or different.
X represents a cross-linking group selected from the cross-linking group group. When a plurality of X's exist, they may be the same or different. ]

[In equation (1'), mA represents an integer from 0 to 5, m represents an integer from 1 to 4, and c represents an integer from 0 or 1. If there are multiple mAs, they may be the same or different.
Ar ⁵ represents an aromatic hydrocarbon group, a heterocyclic group, or a group in which an aromatic hydrocarbon ring and a heterocycle are directly bonded, and these groups may have a substituent.
Ar ⁴ and Ar ⁶ each independently represent an arylene group or a divalent heterocyclic group, and these groups may have a substituent.
Ar ⁴ , Ar ⁵ and Ar ⁶ each form a ring by directly or via an oxygen atom or a sulfur atom with a group other than the group bonded to the nitrogen atom to which the group is bonded. You may be.
K ^A is an alkylene group, a cycloalkylene group, an arylene group, a divalent heterocyclic group, -NR '' - group represented by an oxygen atom or a sulfur atom, these groups other than oxygen and sulfur atoms May have a substituent. R ″ represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, and these groups other than the hydrogen atom may have a substituent. If K ^A there are a plurality, they may be the same or different.
X'represents a cross-linking group, a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group selected from the cross-linking group group, and these groups other than the hydrogen atom have a substituent. You may. However, at least one X'is a cross-linking group selected from the cross-linking group group. ]
[4] The light emitting device according to any one of [1] to [3], wherein the phosphorescent transition metal complex is a metal complex represented by the formula (1-A).

[In formula (1-A), M represents a ruthenium atom, a rhodium atom, a palladium atom, an iridium atom or a platinum atom.
n ¹ represents an integer of 1 or more, and n ² represents an integer of 0 or more. However, when M is a ruthenium atom, a rhodium atom or an iridium atom, n ¹ + n ² is 3, and when M is a palladium atom or a platinum atom, n ¹ + n ² is 2.
E ¹ represents a carbon atom or a nitrogen atom. If there are multiple E ¹ , they may be the same or different.
Ring L ^1A represents a pyridine ring, a diazabenzene ring, an azanaphthalene ring, a diazanaphthalene ring, a triazole ring or a diazole ring, and these rings may have a substituent. When a plurality of the substituents are present, the plurality of substituents may be bonded to each other to form a ring together with the atoms to which they are bonded. If there are multiple rings L ^1A , they may be the same or different.
E ^21A , E ^22A , E ^23A and E ^24A each independently represent a nitrogen atom or a carbon atom. However, the ring L ^2A represents a benzene ring, a pyridine ring or a diazabenzene ring. If E ^21A is a nitrogen atom, then R ^21A does not exist. If E ^22A is a nitrogen atom, then R ^22A does not exist. If E ^23A is a nitrogen atom, then R ^23A does not exist. If E ^24A is a nitrogen atom, then R ^24A does not exist. When a plurality of E ^21A , E ^22A , E ^23A and E ^24A exist, they may be the same or different from each other.
R ^21A , R ^22A , R ^23A and R ^24A are independently hydrogen atom, alkyl group, cycloalkyl group, alkoxy group, cycloalkoxy group, aryl group, aryloxy group, monovalent heterocyclic group and substituted amino. Representing a group or a halogen atom, these groups other than the hydrogen atom may have a substituent. When there are a plurality of R ^21A , R ^22A , R ^23A and R ^24A , they may be the same or different from each other. The substituents R ^21A and R ^22A , R ^22A and R ^23A , R ^23A and R ^24A , and the substituents that ring L ^1A may have and R ^21A may be bonded to each other to form a ring. ..
A ¹ −G ¹ −A ² represents an anionic bidentate ligand. A ¹ and A ² independently represent a carbon atom, an oxygen atom, or a nitrogen atom, and these atoms may be atoms constituting a ring. G ¹ represents a single bond or an atomic group constituting a bidentate ligand together with A ¹ and A ² . When there are a plurality of A ^1- G ^1- A ² , they may be the same or different. ]
[5] The metal complex represented by the formula (1-A) is a formula (1-B1), a formula (1-B2), a formula (1-B3), a formula (1-B4) or a formula (1-B4). The light emitting device according to [4], which is a metal complex represented by B5).

[In formulas (1-B1) to (1 to B5), M, n ¹ , n ² , R ^21A , R ^22A , R ^23A , R ^24A and A ^1- G ^1- A ² have the same meanings as described above. Represents.
n ¹¹ and n ¹² independently represent 1 or 2, respectively. However, when M is a ruthenium atom, a rhodium atom or an iridium atom, n ¹¹ + n ¹² is 3, and when M is a palladium atom or a platinum atom, n ¹¹ + n ¹² is 2.
R ^11B , R ^12B , R ^13B , R ^14B , R ^15B , R ^16B , R ^17B and R ^18B are independently hydrogen atoms, alkyl groups, cycloalkyl groups, alkoxy groups, cycloalkoxy groups, aryl groups and aryls, respectively. It represents an oxy group, a monovalent heterocyclic group, a substituted amino group or a halogen atom, and these groups other than the hydrogen atom may have a substituent. If there are multiple R ^11B , R ^12B , R ^13B , R ^14B , R ^15B , R ^16B , R ^17B and R ^18B , they may be the same or different.
In formula (1-B1), R ^11B and R ^12B , R ^12B and R ^13B , R ^13B and R ^14B , and R ^11B and R ^21A may be combined to form a ring, respectively.
In equation (1-B2), R ^13B and R ^14B , R ^13B and R ^15B , R ^15B and R ^16B , R ^16B and R ^17B , R ^17B and R ^18B , and R ^18B and R ^21A are combined, respectively. May form a ring.
In equation (1-B3), R ^11B and R ^12B , R ^12B and R ^13B , R ^13B and R ^14B , R ^11B and R ^21A , R ^13B and R ^15B , R ^15B and R ^16B , R ^16B and R ^17B , R ^17B and R ^18B , and R ^18B and R ^21A may be combined to form a ring, respectively.
In equation (1-B4), R ^11B and R ^18B , R ^14B and R ^15B , R ^15B and R ^16B , R ^16B and R ^17B , R ^17B and R ^18B , and R ^11B and R ^21A are combined, respectively. May form a ring.
In equation (1-B5), R ^11B and R ^12B , R ^12B and R ^18B , R ^15B and R ^16B , R ^16B and R ^17B , R ^17B and R ^18B , and R ^11B and R ^21A are combined, respectively. May form a ring. ]
[6] The light emitting device according to any one of [1] to [5], wherein the first organic layer and the second organic layer are in contact with each other.
[7] A cathode, a first organic layer containing a compound having a cross-linking group and a phosphorescent transition metal complex, a second organic layer containing a cross-linked product of the same compound as the compound having the cross-linking group, and A light emitting element having an anode in this order and having a compound having a cross-linking group contained in the first organic layer in an amount of 2 to 10% by mass based on the total mass of the first organic layer. The method for producing a light emitting element, wherein the first organic layer and the second organic layer are formed by a coating method.

According to the present invention, it is possible to provide a light emitting element having excellent luminous efficiency.

It is the schematic which shows an example of the light emitting element in one aspect of this invention.

Hereinafter, preferred embodiments of the present invention will be described in detail.

<Explanation of common terms>
Unless otherwise specified, the terms commonly used in the present specification have the following meanings.

Me represents a methyl group, Et represents an ethyl group, Bu represents a butyl group, i-Pr represents an isopropyl group, and t-Bu represents a tert-butyl group.

The hydrogen atom may be a deuterium atom or a light hydrogen atom.

In the formula representing the metal complex, the solid line representing the bond between the ligand and the central metal means a covalent bond or a coordination bond.

The "polymer compound" has a molecular weight distribution, the number average molecular weight in terms of polystyrene means a polymer which is ^{1 × 10 3 ~1 × 10 8} .

By "low molecular compound" does not have a molecular weight distribution, molecular weight means a 1 × 10 ⁴ or less of the compound.

The “constituent unit” means a unit existing in one or more in a polymer compound. Constituent units that are present in two or more in a polymer compound are usually referred to as "repeating units".

The "alkyl group" may be either linear or branched. The number of carbon atoms of the linear alkyl group is usually 1 to 50, preferably 3 to 30, and more preferably 4 to 20, not including the number of carbon atoms of the substituent. The number of carbon atoms of the branched alkyl group is usually 3 to 50, preferably 3 to 30, and more preferably 4 to 20, not including the number of carbon atoms of the substituent.

The alkyl group may have a substituent, for example, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a 2-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isoamyl group, 2-Ethylbutyl group, hexyl group, heptyl group, octyl group, 2-ethylhexyl group, 3-propylheptyl group, decyl group, 3,7-dimethyloctyl group, 2-ethyloctyl group, 2-hexyldecyl group, dodecyl group. , And a group in which the hydrogen atom in these groups is substituted with a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, a fluorine atom or the like (for example, a trifluoromethyl group, a pentafluoroethyl group, a perfluorobutyl group). , Perfluorohexyl group, perfluorooctyl group, 3-phenylpropyl group, 3- (4-methylphenyl) propyl group, 3- (3,5-di-hexylphenyl) propyl group, 6-ethyloxyhexyl group) Can be mentioned.

The number of carbon atoms of the "cycloalkyl group" is usually 3 to 50, preferably 3 to 30, and more preferably 4 to 20, not including the number of carbon atoms of the substituent.

The cycloalkyl group may have a substituent, and examples thereof include a cyclohexyl group, a methylcyclohexyl group, and an ethylcyclohexyl group.

"Aryl group" means the remaining atomic group excluding one hydrogen atom directly bonded to a carbon atom forming a ring from an aromatic hydrocarbon. The number of carbon atoms of the aryl group is usually 6 to 60, preferably 6 to 20, and more preferably 6 to 10 without including the number of carbon atoms of the substituent.

The aryl group may have a substituent, for example, a phenyl group, a 1-naphthyl group, a 2-naphthyl group, a 1-anthrasenyl group, a 2-anthrasenyl group, a 9-anthrasenyl group, a 1-pyrenyl group, 2 -Pyrenyl group, 4-pyrenyl group, 2-fluorenyl group, 3-fluorenyl group, 4-fluorenyl group, 2-phenylphenyl group, 3-phenylphenyl group, 4-phenylphenyl group, and hydrogen atoms in these groups. However, examples thereof include groups substituted with an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, a fluorine atom and the like.

The "alkoxy group" may be either linear or branched. The number of carbon atoms of the linear alkoxy group is usually 1 to 40, preferably 4 to 10 without including the number of carbon atoms of the substituent. The number of carbon atoms of the branched alkoxy group is usually 3 to 40, preferably 4 to 10 without including the number of carbon atoms of the substituent.

The alkoxy group may have a substituent, for example, a methoxy group, an ethoxy group, a propyloxy group, an isopropyloxy group, a butyloxy group, an isobutyloxy group, a tert-butyloxy group, a pentyloxy group, a hexyloxy group, and the like. Heptyloxy group, octyloxy group, 2-ethylhexyloxy group, nonyloxy group, decyloxy group, 3,7-dimethyloctyloxy group, lauryloxy group, and the hydrogen atom in these groups are cycloalkyl group, alkoxy group, Examples thereof include a cycloalkoxy group, an aryl group, a group substituted with a fluorine atom and the like.

The number of carbon atoms of the "cycloalkoxy group" is usually 3 to 40, preferably 4 to 10 without including the number of carbon atoms of the substituent.

The cycloalkoxy group may have a substituent, for example, the hydrogen atom in the cyclohexyloxy group and the cyclohexyloxy group is substituted with a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, a fluorine atom or the like. The group can be mentioned.
Can be mentioned.

The number of carbon atoms of the "aryloxy group" is usually 6 to 60, preferably 6 to 48, not including the number of carbon atoms of the substituent.

The aryloxy group may have a substituent, for example, a phenoxy group, a 1-naphthyloxy group, a 2-naphthyloxy group, a 1-antrasenyloxy group, a 9-anthrasenyloxy group, 1-. Examples thereof include a pyrenyloxy group and a group in which a hydrogen atom in these groups is substituted with an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, a fluorine atom or the like.

The "p-valent heterocyclic group" (p represents an integer of 1 or more) is p of hydrogen atoms directly bonded to carbon atoms or heteroatoms constituting the ring from the heterocyclic compound. It means the remaining atomic group excluding the hydrogen atom of. Among the p-valent heterocyclic groups, it is the remaining atomic group obtained by removing p hydrogen atoms from the hydrogen atoms directly bonded to the carbon atoms or heteroatoms constituting the ring from the aromatic heterocyclic compound. A "p-valent aromatic heterocyclic group" is preferred.

The "aromatic heterocyclic compound" is a heterocyclic compound such as oxadiazole, thiadiazole, thiazole, oxazole, thiophene, pyrrole, phosphor, furan, pyridine, pyrazine, pyrimidine, triazine, pyridazine, quinoline, isoquinoline, carbazole, and dibenzophosphol. Even if the compound whose ring itself exhibits aromaticity and the heterocycle itself such as phenoxazine, phenothiazine, dibenzoborol, dibenzosilol, and benzopyran do not exhibit aromaticity, the aromatic ring is fused to the heterocycle. Means a compound.

The number of carbon atoms of the monovalent heterocyclic group does not include the number of carbon atoms of the substituent and is usually 2 to 60, preferably 4 to 20.

The monovalent heterocyclic group may have a substituent, for example, a thienyl group, a pyrrolyl group, a furyl group, a pyridyl group, a piperidinyl group, a quinolinyl group, an isoquinolinyl group, a pyrimidinyl group, a triazinyl group, and these. Examples thereof include a group in which the hydrogen atom in the group is substituted with an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group or the like.

The "halogen atom" refers to a fluorine atom, a chlorine atom, a bromine atom or an iodine atom.

The "amino group" may have a substituent, and a substituted amino group is preferable. As the substituent contained in the amino group, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group is preferable.

Examples of the substituted amino group include a dialkylamino group, a dicycloalkylamino group and a diarylamino group.

Examples of the amino group include a dimethylamino group, a diethylamino group, a diphenylamino group, a bis (4-methylphenyl) amino group, a bis (4-tert-butylphenyl) amino group, and a bis (3,5-di-tert-). Butylphenyl) amino groups can be mentioned.

The "alkenyl group" may be either linear or branched. The number of carbon atoms of the linear alkenyl group is usually 2 to 30, not including the number of carbon atoms of the substituent, and is preferably 3 to 20. The number of carbon atoms of the branched alkenyl group is usually 3 to 30, preferably 4 to 20, not including the number of carbon atoms of the substituent.

The number of carbon atoms of the "cycloalkenyl group" is usually 3 to 30, preferably 4 to 20, not including the number of carbon atoms of the substituent.

The alkenyl group and the cycloalkenyl group may have a substituent, for example, a vinyl group, a 1-propenyl group, a 2-propenyl group, a 2-butenyl group, a 3-butenyl group, a 3-pentenyl group, a 4- A pentenyl group, a 1-hexenyl group, a 5-hexenyl group, a 7-octenyl group, a 1-cyclopentyl-1-yl group, a 1-cyclohexyl-1-yl group, and a group in which these groups have a substituent described later. Can be mentioned.

The "alkynyl group" may be either linear or branched. The number of carbon atoms of the alkynyl group is usually 2 to 20, preferably 3 to 20, not including the carbon atom of the substituent. The number of carbon atoms of the branched alkynyl group is usually 4 to 30, preferably 4 to 20, not including the carbon atom of the substituent.

The alkynyl group may have a substituent, for example, an ethynyl group, a 1-propynyl group, a 2-propynyl group, a 2-butynyl group, a 3-butynyl group, a 3-pentynyl group, a 4-pentynyl group, 1 Examples thereof include a −hexynyl group, a 5-hexynyl group, and a group in which these groups have a substituent described later.

The "arylene group" means the remaining atomic group excluding two hydrogen atoms directly bonded to the carbon atoms constituting the ring from the aromatic hydrocarbon. The number of carbon atoms of the arylene group is usually 6 to 60, preferably 6 to 30, and more preferably 6 to 18, not including the number of carbon atoms of the substituent.

The arylene group may have a substituent, for example, a phenylene group, a biphenyldiyl group, a naphthalenediyl group, an anthracendiyl group, a phenanthrendyl group, a dihydrophenantrenidyl group, a naphthalsendiyl group, a fluorinatedyl group, a pyrenedyl group. , Perylenediyl group, chrysendiyl group, and groups in which these groups have a substituent described later are mentioned, and are preferably groups represented by the formulas (A-1) to (A-21). The arylene group includes a group in which a plurality of these groups are bonded.

［式中、Ｒ及びＲ^aは、それぞれ独立に、水素原子、アルキル基、シクロアルキル基、アリール基又は１価の複素環基を表す。複数存在するＲ及びＲ^aは、各々、同一でも異なっていてもよく、Ｒ^a同士は互いに結合して、それぞれが結合する原子と共に環を形成していてもよい。］

[Wherein, R and R ^a each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group. A plurality of R and ^Ra may be the same or different from each other, and R ^a may be bonded to each other to form a ring together with the atoms to which each is bonded. ]

The number of carbon atoms of the divalent heterocyclic group is usually 2 to 60, preferably 3 to 20, and more preferably 4 to 15, not including the number of carbon atoms of the substituent.

The divalent heterocyclic group may have a substituent, for example, pyridine, diazabenzene, triazine, azanaphthalene, diazanaphthalene, carbazole, dibenzofuran, dibenzothiophene, dibenzosilol, phenoxazine, phenothiazine, acridine, Dihydroacridine, furan, thiophene, azole, diazole, triazole, 5,7,12,14-tetrahydroquino [2,3-b] acridine, oxazole, 1,3,4-oxadiazole, thiazole, 1,3 Examples thereof include a divalent group obtained by removing two hydrogen atoms from the hydrogen atom directly bonded to the carbon atom or the hetero atom forming the ring from 4-thiazole, preferably from the formula (AA-1) to. It is a group represented by the formula (AA-36). The divalent heterocyclic group includes a group in which a plurality of these groups are bonded.

［式中、Ｒ及びＲ^aは、前記と同じ意味を表す。］

[In the formula, R and ^Ra have the same meanings as described above. ]

The "crosslinked group" is a group capable of forming a new bond by subjecting it to heating, ultraviolet irradiation, near-ultraviolet irradiation, visible light irradiation, infrared irradiation, radical reaction, or the like, and is preferably the above-mentioned group. It is a cross-linking group represented by the formulas (XL-1) to (XL-19) of the cross-linking group group.

The "substituent" is, for example, a halogen atom, a cyano group, an alkyl group, a cycloalkyl group, an aryl group, a monovalent heterocyclic group, an alkoxy group, a cycloalkoxy group, an aryloxy group, an amino group, a substituted amino group, and the like. Represents an alkenyl group, a cycloalkenyl group, or an alkynyl group. The substituent may be a cross-linking group. In the present specification, when it is expressed that a group may have a substituent, it means that the group may have at least one group listed as the substituent. To do.

<Light emitting element>
Next, the light emitting element according to this embodiment will be described.
The light emitting element according to the present embodiment contains a cathode, a first organic layer containing a compound having a cross-linking group and a phosphorescent transition metal complex, and a cross-linked product of the same compound as the compound having the cross-linking group. The amount of the compound having the two organic layers and the anode in this order and having the cross-linking group contained in the first organic layer is 2 to 10% by mass with respect to the total mass of the first organic layer. It is a light emitting element.

Examples of the method for forming the first organic layer and the second organic layer include a dry method such as a vacuum vapor deposition method and a wet method such as a spin coating method and an inkjet printing method, and the wet method is preferable.

When the first organic layer is formed by a wet method, it is preferable to use the first ink described later.

When the second organic layer is formed by a wet method, it is preferable to use a second ink described later. After forming the second organic layer, the compound having a cross-linking group contained in the second organic layer can be crosslinked by heating or irradiating with light. Heating is preferable as a method for cross-linking the compound having a cross-linking group contained in the second organic layer. The second organic layer contains a crosslinked product of a compound having a crosslinking group.

The heating temperature for crosslinking is usually 50 ° C. to 300 ° C., preferably 50 ° C. to 260 ° C., more preferably 130 ° C. to 230 ° C., and even more preferably 180 ° C. to 210 ° C. ..
The heating time is usually 0.1 minutes to 1000 minutes, preferably 0.5 minutes to 500 minutes, more preferably 1 minute to 120 minutes, still more preferably 10 minutes to 60 minutes. ..

Examples of the type of light used for light irradiation include ultraviolet light, near-ultraviolet light, and visible light.

<First organic layer>
The first organic layer in one embodiment of the present invention contains a compound having a cross-linking group and a phosphorescent transition metal complex, and the proportion of the compound having the cross-linking group contained in the first organic layer is the first. It is 2 to 10% by mass based on the total mass of the organic layer of 1.

Examples of the method for analyzing the components contained in the first organic layer include chemical separation analysis such as extraction, infrared spectroscopy (also referred to as IR), nuclear magnetic resonance spectroscopy (also referred to as NMR), and mass spectrometry. An instrumental analysis method such as a method (also referred to as MS), and an analysis method combining a chemical separation analysis method and an instrumental analysis method can be mentioned.

For example, when the first organic layer is formed by a wet method, the following methods can be mentioned as a method for quantifying the compound having a cross-linking group contained in the first organic layer.
First, the first organic layer is separated from the lamination with the cathode, the first organic layer, the second organic layer, and the anode. Examples of the method for separating the first organic layer include a method of dissolving the components of the first organic layer in a solvent such as toluene, xylene, chloroform, or tetrahydrofuran. Next, the mass of the separated first organic layer is measured. Then, the compound having a cross-linking group contained in the first organic layer separated by analysis by nuclear magnetic resonance spectroscopy or mass spectrometry is quantified.

<Compound with cross-linking group>
A compound having a cross-linking group contained in the first organic layer will be described.
The first organic layer may contain one compound having a cross-linking group of the first organic layer alone, or two or more compounds may be contained.

Since the luminous efficiency of the light emitting device is more excellent, the "compound having a cross-linking group" is a compound having at least one cross-linking group selected from the group of cross-linking groups consisting of the above formulas (XL-1) to (XL-19). Is preferable.

As the cross-linking group selected from the cross-linking group group, since the light emitting efficiency of the light emitting element of the present invention is more excellent, the formulas (XL-1) to (XL-4) and the formulas (XL-7) to (XL-10) are used. ) Or a cross-linking group represented by the formulas (XL-16) to (XL-19), and is represented by the formulas (XL-1) and (XL-16) to (XL-19). It is more preferably a cross-linking group represented by the formula (XL-1) or (XL-17), and further preferably a cross-linking group represented by the formula (XL-17). Is even more preferable.

The "compound having a cross-linking group" may be a low molecular weight compound or a high molecular weight compound.
The compound having a cross-linking group which is a low-molecular-weight compound is, for example, a low-molecular-weight compound having at least one cross-linking group selected from the group of cross-linking groups. Examples of the low molecular weight compound include low molecular weight compounds represented by formulas (3-1) to (3-16).

The "compound having a cross-linking group" is preferably a polymer compound containing a structural unit having at least one cross-linking group selected from the group of cross-linking groups (hereinafter, "a cross-linking group-containing polymer compound of the first organic layer"). Also called.).

The structural unit having at least one cross-linking group selected from the cross-linking group group contained in the cross-linking group-containing polymer compound of the first organic layer is a structure represented by the above formula (1) or the above formula (1'). It is preferably a unit, and more preferably a structural unit represented by the above formula (1).

The structural unit having at least one kind of cross-linking group selected from the cross-linking group group may be a structural unit represented by the formulas (1 ″ -1) to (1 ″ -5).

The cross-linking group-containing polymer compound of the first organic layer may contain two or more structural units having at least one cross-linking group selected from the cross-linking group group. In this case, it is preferable that at least two structural units having at least one cross-linking group selected from the cross-linking group group have different cross-linking groups. As a combination of different cross-linking groups, the formula (XL-1), the formula (XL-2), the formula (XL-5) to the formula (XL-8) or the formula (XL-14) to the formula (XL-16) are used. At least one selected from the cross-linking groups represented by the formulas (XL-3), formula (XL-4), formula (XL-13) or formulas (XL-17) to formulas (XL-19). The combination with at least one selected from the cross-linking groups is preferable, and the combination of the cross-linking group represented by the formula (XL-1) and the cross-linking group represented by the formula (XL-17) is more preferable.

The structural unit nA represented by the formula (1) is preferably an integer of 0 to 3, more preferably an integer of 0 to 2, and further preferably 0 because the luminous efficiency of the light emitting element is more excellent. is there.

n is preferably 2 because the luminous efficiency of the light emitting element is more excellent.

Ar ³ is an aromatic hydrocarbon group which may have a substituent because the luminous efficiency of the light emitting device is more excellent.

The number of carbon atoms of the aromatic hydrocarbon group represented by Ar ³ is usually 6 to 60, preferably 6 to 30, and more preferably 6 to 18, not including the number of carbon atoms of the substituent. is there.

The example and preferred range of the arylene group portion excluding the n substituents of the aromatic hydrocarbon group represented by Ar ³ is the same as the example and preferred range of the arylene group represented by Ar ^Y1 described later.

The number of carbon atoms of the heterocyclic group represented by Ar ³ is usually 2 to 60, preferably 3 to 30, and more preferably 4 to 18, not including the number of carbon atoms of the substituent.

Examples and preferable ranges of the divalent heterocyclic group portion excluding the n substituents of the heterocyclic group represented by Ar ³ are the example of the divalent heterocyclic group represented by Ar ^Y1 described later and preferable. Same as range.

The examples and preferred ranges of substituents represented by Ar ³ may have are the same as the examples and preferred ranges of substituents represented by Ar ^Y1 described below.

The number of carbon atoms of the alkylene group represented by L ^A is not including the carbon atom number of substituent is usually 1 to 20. The number of carbon atoms a cycloalkylene group represented by L ^A is not including the carbon atom number of substituent is usually 3 to 20.

Alkylene group and cycloalkylene group represented by L ^A may have a substituent, for example, methylene group, ethylene group, propylene group, butylene group, hexylene group, a cyclohexylene group, octylene group and, Examples thereof include a group in which the hydrogen atom in these groups is substituted with an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, a monovalent heterocyclic group, a fluorine atom or the like.

L Examples and preferred ranges of the arylene group and divalent heterocyclic group represented by ^A are the same as examples and preferred ranges of the arylene group and divalent heterocyclic group represented by later-described Ar ^Y1.

L ^A, since the production of the bridging group-containing polymer compound of the first organic layer becomes easy, it is preferable an arylene group or an alkylene group. These groups may have substituents.

L ^A substituent which may be possessed represented by an alkyl group, a cycloalkyl group, an alkoxy group, cycloalkoxy group, an aryl group, a monovalent heterocyclic group, a substituted amino group, a fluorine atom, a cyano group Alternatively, it is preferably a cross-linking group selected from the cross-linking group group. These groups may further have substituents.

Since the luminous efficiency of the light emitting element of X is more excellent, the formulas (XL-1) to (XL-4), the formulas (XL-7) to the formulas (XL-10), or the formulas (XL-16) to the formulas (XL-16) It is preferably a cross-linking group represented by the formula (XL-19), more preferably a cross-linking group represented by the formulas (XL-1) and (XL-16) to (XL-19). It is more preferably a cross-linking group represented by (XL-1) or the formula (XL-17), and particularly preferably a cross-linking group represented by the formula (XL-17).

Since the structural unit represented by the formula (1) has excellent stability of the cross-linking group-containing polymer compound of the first organic layer, the total of the structural units contained in the cross-linking group-containing polymer compound of the first organic layer With respect to the amount, it is preferably 0.5 to 80 mol%, more preferably 3 to 65 mol%, further preferably 5 to 50 mol%, and particularly preferably 6 to 10 mol%.

The structural unit represented by the formula (1) may contain only one type or two or more types in the cross-linking group-containing polymer compound of the first organic layer.

When the cross-linking group-containing polymer compound of the first organic layer contains two or more structural units represented by the formula (1), at least two structural units represented by the formula (1) are represented by X. It is preferable that the cross-linking groups to be formed are different from each other.

The structural unit mA represented by the equation (1') is preferably an integer of 0 to 3 because the luminous efficiency of the light emitting element is more excellent.
m is preferably 1 or 2 because the luminous efficiency of the light emitting element is more excellent.

c is preferably 0 because the crosslinkable group-containing polymer compound of the first organic layer can be easily produced and the luminous efficiency of the light emitting device is more excellent.

Ar ⁵ is an aromatic hydrocarbon group which may have a substituent because the luminous efficiency of the light emitting device is more excellent.

The definition and example of the arylene group portion excluding the m substituents of the aromatic hydrocarbon group represented by Ar ⁵ are the same as the definition and example of the arylene group represented by Ar ^{X 2} in the formula (X) described later. Is.

The definition and example of the divalent heterocyclic group portion excluding the m substituents of the heterocyclic group represented by Ar ⁵ are the divalent heterocyclic group represented by Ar ^{X 2} in the formula (X) described later. It is the same as the definition and example of.

The definition and example of a divalent group excluding the m substituents of the group in which the aromatic hydrocarbon ring represented by Ar ⁵ and the heterocyclic ring are directly bonded are represented by Ar ^{X 2} in the formula (X) described later. The definition and example of a divalent group in which an areylene group and a divalent heterocyclic group are directly bonded are the same.

Ar ⁴ and Ar ⁶ are arylene groups which may have a substituent because the luminous efficiency of the light emitting device is more excellent.

Definitions and examples of arylene groups and divalent heterocyclic groups represented by Ar ⁴ and Ar ⁶ are for the arylene groups and divalent heterocyclic groups represented by Ar ^X1 and Ar ^X3 in the formula (X) described later. Same as definition and example.

Alkylene group represented by K ^A, definitions and examples of cycloalkylene group, an arylene group, and divalent heterocyclic group are each an alkylene group represented by L ^A, a cycloalkylene group, an arylene group, and divalent It is the same as the definition and example of the heterocyclic group of.

K ^A, so the production of the bridging group-containing polymer compound of the first organic layer becomes easier, preferably, is preferably an arylene group or an alkylene group. These groups may have substituents.

Examples and preferred ranges of the substituent which may be possessed by the groups represented by K ^A is the same as the example and preferred ranges of the substituents may have the group represented by L ^A.

The definition and example of the cross-linking group represented by X'are the same as the definition and example of X described above.

The structural unit represented by the formula (1') is a structural unit contained in the cross-linking group-containing polymer compound of the first organic layer because the stability of the cross-linking group-containing polymer compound of the first organic layer is excellent. It is preferably 0.5 to 50 mol% with respect to the total amount.

The structural unit represented by the formula (1') may contain only one type or two or more types in the cross-linking group-containing polymer compound of the first organic layer.

When the cross-linking group-containing polymer compound of the first organic layer contains two or more structural units represented by the formula (1'), at least two structural units represented by the formula (1') are X. It is preferable that the cross-linking groups represented by'are different from each other.

-Preferable Aspects of the Constituent Unit Represented by the Formula (1) or (1') The structural unit represented by the formula (1) is represented by, for example, the formulas (1-1) to (1-30). Examples of the structural unit represented by the equation (1') include the structural units represented by the equations (1'-1) to (1'-9). Among these, it is preferably a structural unit represented by the formulas (1-1) to (1-9) or (1-30), and more preferably the formulas (1-1) to (1-9). ) Is a structural unit.

[Other building blocks]
Since the cross-linking group-containing polymer compound of the first organic layer is excellent in hole transportability, it is preferable to further contain a structural unit represented by the formula (X).

［式（Ｘ）中、ａ^X1及びａ^X2は、それぞれ独立に、０以上の整数を表す。
Ａｒ^X1及びＡｒ^X3は、それぞれ独立に、アリーレン基又は２価の複素環基を表し、これらの基は置換基を有していてもよい。
Ａｒ^X2及びＡｒ^X4は、それぞれ独立に、アリーレン基、２価の複素環基、又は、アリーレン基と２価の複素環基とが直接結合した２価の基を表し、これらの基は置換基を有していてもよい。Ａｒ^X2及びＡｒ^X4が複数存在する場合、それらは同一でも異なっていてもよい。
Ｒ^X1、Ｒ^X2及びＲ^X3は、それぞれ独立に、水素原子、アルキル基、シクロアルキル基、アリール基又は１価の複素環基を表し、水素原子以外のこれらの基は置換基を有していてもよい。Ｒ^X2及びＲ^X3が複数存在する場合、それらは同一でも異なっていてもよい。］

[In equation (X), a ^X1 and a ^X2 each independently represent an integer of 0 or more.
Ar ^X1 and Ar ^X3 independently represent an arylene group or a divalent heterocyclic group, and these groups may have a substituent.
Ar ^X2 and Ar ^X4 each independently represent an arylene group, a divalent heterocyclic group, or a divalent group in which an arylene group and a divalent heterocyclic group are directly bonded, and these groups are substituents. May have. If there are multiple Ar ^X2 and Ar ^X4 , they may be the same or different.
R ^X1 , R ^{X 2} and R ^{X 3} independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, and these groups other than the hydrogen atom have a substituent. You may. When there are a plurality of R ^X2 and R ^X3 , they may be the same or different. ]

Since the luminous efficiency of the light emitting device of the present invention is more excellent, a ^X1 is preferably 2 or less, and more preferably 1.

Since the luminous efficiency of the light emitting element of the present invention is more excellent, a ^X2 is preferably 2 or less, and more preferably 0.

R ^X1 to R ^X3 is an alkyl group, a cycloalkyl group, preferably an aryl group or a monovalent heterocyclic group, more preferably an aryl group. These groups may have substituents.

The arylene group represented by Ar ^X1 and Ar ^X3 is more preferably a group represented by the formula (A-1) or the formula (A-9), and is a group represented by the formula (A-1). It is more preferable to have. These groups may have substituents.

The divalent heterocyclic groups represented by Ar ^X1 and Ar ^X3 are groups represented by the formulas (AA-1), formula (AA-2) or formulas (AA-7) to formulas (AA-26). More preferably. These groups may have substituents.

Ar ^X1 and Ar ^X3 are preferably arylene groups which may have a substituent.

The arylene groups represented by Ar ^X2 and Ar ^X4 are of formula (A-1), formula (A-6), formula (A-7), formula (A-9) to formula (A-11) or formula (A-11). It is more preferably the group represented by A-19), and further preferably the group represented by the formula (A-9). These groups may have substituents.

The more preferred range of the divalent heterocyclic groups represented by Ar ^X2 and Ar ^X4 is the same as the more preferred range of the divalent heterocyclic groups represented by Ar ^X1 and Ar ^X3 .

In the divalent group in which the arylene group represented by Ar ^X2 and Ar ^X4 and the divalent heterocyclic group are directly bonded, the more preferable range and the more preferable range of the arylene group and the divalent heterocyclic group are, respectively. It is the same as the more preferable range of the arylene group and the divalent heterocyclic group represented by Ar ^X1 and Ar ^X3 , and the more preferable range.

Examples of the divalent group an arylene group and a divalent heterocyclic group is bonded directly represented by Ar ^X2 and Ar ^X4, for example, represented by the formula ^(Ar X5 -1) ~ formula ^(Ar X5 -4) Groups may be mentioned, and these may have substituents.

［式（Ａｒ^Ｘ５−３）中、Ｒ^XXは、水素原子、アルキル基、シクロアルキル基、アリール基又は１価の複素環基を表し、水素原子以外のこれらの基は置換基を有していてもよい。］

[In the formula (Ar ^X5-3 ), R ^XX represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, and these groups other than the hydrogen atom have a substituent. You may. ]

Ar ^X2 and Ar ^X4 are preferably arylene groups which may have a substituent.

The substituents that the groups represented by Ar ^{X1 to} Ar ^X4 and R ^{X1 to} R ^X3 may have are preferably an alkyl group, a cycloalkyl group or an aryl group, and more preferably an alkyl group. These groups may further have substituents.

The structural unit represented by the formula (X) is preferably a structural unit represented by the formulas (X-1) to (X-7), and more preferably represented by the formula (X-4). It is a structural unit.

［式（Ｘ−１）〜（Ｘ−７）中、Ｒ^X4及びＲ^X5は、それぞれ独立に、水素原子、アルキル基、シクロアルキル基、アルコキシ基、シクロアルコキシ基、アリール基、アリールオキシ基、ハロゲン原子、１価の複素環基又はシアノ基を表し、水素原子以外のこれらの基は置換基を有していてもよい。複数存在するＲ^X4は、同一でも異なっていてもよい。複数存在するＲ^X5は、同一でも異なっていてもよく、隣接するＲ^X5同士は互いに結合して、それぞれが結合する炭素原子と共に環を形成していてもよい。］

[In formulas (X-1) to (X-7), ^RX4 and ^RX5 are independently hydrogen atoms, alkyl groups, cycloalkyl groups, alkoxy groups, cycloalkoxy groups, aryl groups, aryloxy groups, respectively. Representing a halogen atom, a monovalent heterocyclic group or a cyano group, these groups other than the hydrogen atom may have a substituent. A plurality of R ^X4s may be the same or different. A plurality of R ^X5s existing may be the same or different, and adjacent ^RX5s may be bonded to each other to form a ring together with the carbon atoms to which they are bonded. ]

Since the structural unit represented by the formula (X) has excellent hole transportability, it is preferably 0.1 to 1 with respect to the total amount of the structural units contained in the cross-linking group-containing polymer compound of the first organic layer. It is 90 mol%, more preferably 1 to 70 mol%, further preferably 10 to 50 mol%, and particularly preferably 30 to 45 mol%.

Examples of the structural unit represented by the formula (X) include the structural units represented by the formulas (X1-1) to (X1-19), preferably the formulas (X1-6) to (X1). It is a structural unit represented by -14).

In the cross-linking group-containing polymer compound of the first organic layer, the structural unit represented by the formula (X) may contain only one type or two or more types.

The crosslinked group-containing polymer compound of the first organic layer is more excellent in luminous efficiency of the light emitting device of the present invention, and therefore preferably further contains a structural unit represented by the formula (Y).

Since the crosslinked group-containing polymer compound of the first organic layer has excellent hole transportability and more excellent luminous efficiency of the light emitting device of the present invention, the structural unit and the formula represented by the formula (X) are further excellent. It is preferable to include the structural unit represented by (Y).

［式（Ｙ）中、Ａｒ^Y1は、アリーレン基、２価の複素環基、又は、アリーレン基と２価の複素環基とが直接結合した２価の基を表し、これらの基は置換基を有していてもよい。］

[In formula (Y), Ar ^Y1 represents an arylene group, a divalent heterocyclic group, or a divalent group in which an arylene group and a divalent heterocyclic group are directly bonded, and these groups are substituents. May have. ]

The arylene group represented by Ar ^Y1 is of the formula (A-1), the formula (A-6), the formula (A-7), the formula (A-9) to the formula (A-11), and the formula (A-13). ) Or a group represented by the formula (A-19), and is represented by the formula (A-1), the formula (A-7), the formula (A-9) or the formula (A-19). It is more preferably a group, and even more preferably a group represented by the formula (A-9). These groups may have substituents.

The divalent heterocyclic group represented by Ar ^Y1 is the formula (AA-4), the formula (AA-10), the formula (AA-13), the formula (AA-15), the formula (AA-18) or the formula. It is preferably a group represented by (AA-20), and is a group represented by the formula (AA-4), the formula (AA-10), the formula (AA-18) or the formula (AA-20). Is more preferable. These groups may have substituents.

In the divalent group in which the arylene group represented by Ar ^Y1 and the divalent heterocyclic group are directly bonded, the more preferable range and the more preferable range of the arylene group and the divalent heterocyclic group are the above-mentioned Ar, respectively. This is the same as the more preferable range of the arylene group represented by ^Y1 and the divalent heterocyclic group, and the more preferable range.

The divalent group in which the arylene group represented by Ar ^Y1 and the divalent heterocyclic group are directly bonded is the arylene group represented by Ar ^X2 and Ar ^X4 of the formula (X) and the divalent heterocyclic group. Examples thereof include those similar to the divalent group in which and is directly bonded.

The substituent that the group represented by Ar ^Y1 may have is preferably an alkyl group, a cycloalkyl group or an aryl group, more preferably an aryl group, and these groups further have a substituent. You may.

Examples of the structural unit represented by the formula (Y) include the structural units represented by the formulas (Y-1) to (Y-7), and from the viewpoint of the luminous efficiency of the light emitting element, the formula (Y-1) It is preferably a structural unit represented by Y-2).

［式（Ｙ−１）中、Ｒ^Y1は、水素原子、アルキル基、シクロアルキル基、アルコキシ基、シクロアルコキシ基、アリール基又は１価の複素環基を表し、水素原子以外のこれらの基は置換基を有していてもよい。複数存在するＲ^Y1は、同一でも異なっていてもよく、隣接するＲ^Y1同士は互いに結合して、それぞれが結合する炭素原子と共に環を形成していてもよい。］

[In formula (Y-1), ^RY1 represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group or a monovalent heterocyclic group, and these groups other than the hydrogen atom are It may have a substituent. A plurality of ^RY1s existing may be the same or different, and adjacent ^RY1s may be bonded to each other to form a ring together with the carbon atoms to which they are bonded. ]

［式（Ｙ−２）中、Ｒ^Y1は前記と同じ意味を表す。
Ｘ^Y1は、−Ｃ(Ｒ^Y2)₂−、−Ｃ(Ｒ^Y2)＝Ｃ(Ｒ^Y2)−又はＣ(Ｒ^Y2)₂−Ｃ(Ｒ^Y2)₂−で表される基を表す。
Ｒ^Y2は、水素原子、アルキル基、シクロアルキル基、アルコキシ基、シクロアルコキシ基、アリール基又は１価の複素環基を表し、水素原子以外のこれらの基は置換基を有していてもよい。
複数存在するＲ^Y2は、同一でも異なっていてもよく、Ｒ^Y2同士は互いに結合して、それぞれが結合する炭素原子と共に環を形成していてもよい。］

[In the formula (Y-2), ^RY1 has the same meaning as described above.
X ^{Y1 _{is, -C (R Y2) 2 -}} , - represents a group represented by ^{- C (R Y2) = C} (R Y2) - , or _{^{C (R Y2) 2 -C (}} R Y2) 2.
^RY2 represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group or a monovalent heterocyclic group, and these groups other than the hydrogen atom may have a substituent. ..
A plurality of ^RY2s existing may be the same or different, and the ^RY2s may be bonded to each other to form a ring together with the carbon atoms to which they are bonded. ]

^RY2 is preferably an alkyl group, a cycloalkyl group or an aryl group, and more preferably an aryl group. These groups may have substituents.

In ^{X Y1, -C (R Y2)} 2 - a combination of the two R ^Y2 in the group represented by the both alkyl groups or cycloalkyl groups, both aryl groups, both monovalent heterocyclic group Or, one is preferably an alkyl group or a cycloalkyl group and the other is an aryl group or a monovalent heterocyclic group. -C (R ^Y2) ₂ - ₂ pieces of combinations of R ^Y2 in the group represented by is preferably one of the other is an aryl group with an alkyl group or a cycloalkyl group. These groups may have substituents. The two existing ^RY2s may be bonded to each other to form a ring with the atoms to which they are bonded. When ^RY2 forms a ring, the group represented by −C ( ^RY2 ) ₂₋ is preferably a group represented by the formulas (YA1) to (YA5). These groups may have substituents.

In ^XY1 , the combination of two RY2s in the group represented by −C ( ^RY2 ) = C ( ^RY2 ) − is ^either an alkyl group or a cycloalkyl group, or one is an alkyl group or a cyclo. It is preferable that the alkyl group is an aryl group and the other is an aryl group. These groups may have substituents.

In ^{X Y1, -C (R Y2)} 2 -C (R Y2) 2 - 4 pieces of R ^Y2 in the group represented by is preferably an optionally substituted alkyl group or a cycloalkyl group Is. A plurality of ^RY2s may be bonded to each other to form a ring with the atoms to which each is bonded. When ^RY2 forms a ring, the groups represented by −C ( ^RY2 ) ₂ −C ( ^RY2 ) ₂₋ are the groups represented by the formulas (Y-B1) to (Y-B5). It is preferable to have. These groups may have substituents.

［式（Ｙ−Ｂ１）、式（Ｙ−Ｂ２）及び式（Ｙ−Ｂ４）中、Ｒ^Y2は前記と同じ意味を表す。］

[In the formula (Y-B1), the formula (Y-B2) and the formula (Y-B4), ^RY2 has the same meaning as described above. ]

［式（Ｙ−３）及び式（Ｙ−４）中、Ｒ^Y1は前記と同じ意味を表す。
Ｒ^Y3は、水素原子、アルキル基、シクロアルキル基、アルコキシ基、シクロアルコキシ基、アリール基又は１価の複素環基を表し、水素原子以外のこれらの基は置換基を有していてもよい。］

[In the formula (Y-3) and the formula (Y-4), ^RY1 has the same meaning as described above.
^RY3 represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group or a monovalent heterocyclic group, and these groups other than the hydrogen atom may have a substituent. .. ]

［式（Ｙ−５）〜式（Ｙ−７）中、Ｒ^Y1は前記を同じ意味を表す。
Ｒ^Y4は、水素原子、アルキル基、シクロアルキル基、アルコキシ基、シクロアルコキシ基、アリール基又は１価の複素環基を表し、水素原子以外のこれらの基は置換基を有していてもよい。］

[In formulas (Y-5) to (Y-7), ^RY1 has the same meaning as described above.
^RY4 represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group or a monovalent heterocyclic group, and these groups other than the hydrogen atom may have a substituent. .. ]

Examples of the structural unit represented by the formula (Y) include the structural units represented by the formulas (Y-11) to (Y-55).

The structural unit in which the cross-linking group-containing polymer compound of the first organic layer contains the structural unit represented by the formula (Y) and Ar ^Y1 is an arylene group has a higher light emitting efficiency of the light emitting element. It is preferably 0.5 to 90 mol%, more preferably 30 to 60 mol%, and further preferably 40, based on the total amount of the structural units contained in the cross-linking group-containing polymer compound of the organic layer 1. ~ 55 mol%.

The structural unit represented by the formula (Y) in which Ar ^Y1 is a divalent heterocyclic group or a divalent group in which an arylene group and a divalent heterocyclic group are directly bonded is a structural unit. Since the cross-linking group-containing polymer compound of the first organic layer has excellent charge transportability, it is preferably 0.5 to 0.5 to the total amount of the structural units contained in the cross-linking group-containing polymer compound of the first organic layer. It is 40 mol%, more preferably 3 to 30 mol%.

The structural unit represented by the formula (Y) may be contained in only one kind or two or more kinds in the cross-linking group-containing polymer compound of the first organic layer.

Examples of the cross-linking group-containing polymer compound of the first organic layer include the polymer compounds P-1 to P-8 shown in Table 1 below. Here, the "other structural unit" means a structural unit other than the structural unit represented by the formula (1), the formula (1'), the formula (1''), the formula (X), and the formula (Y). To do.

［表中、ｐ’、ｑ’、ｒ’、ｓ’及びｔ’は、各構成単位のモル比率を表す。ｐ’＋ｑ’＋ｒ’＋ｓ’＋ｔ’＝１００であり、且つ、７０≦ｐ’＋ｑ’＋ｒ’＋ｓ’≦１００である。］

[In the table, p', q', r', s'and t'represent the molar ratio of each structural unit. p'+ q'+ r'+ s'+ t'= 100, and 70 ≦ p'+ q'+ r'+ s'≦ 100. ]

The cross-linking group-containing polymer compound of the first organic layer may be any of a block copolymer, a random copolymer, an alternating copolymer, a graft copolymer, and other embodiments. However, it is preferable that the copolymer is a copolymer of a plurality of kinds of raw material monomers.

The number average molecular weight in terms of polystyrene bridging group containing polymer compound of the first organic layer is preferably ^{5 × 10 3 ~1 × 10 6} , more preferably from ^{1 × 10 4 ~5 × 10 5} , More preferably, it is 1.5 × 10 ⁴ to 1 × 10 ⁵ .

[Method for Producing Crosslinking Group-Containing Polymer Compound in First Organic Layer]
The crosslinkable group-containing polymer compound of the first organic layer can be produced by using a known polymerization method described in Chemical Review (Chem. Rev.), Vol. 109, pp. 897-1091 (2009). A method of polymerizing by a coupling reaction using a transition metal catalyst such as Suzuki reaction, Yamamoto reaction, Buchwald reaction, Stille reaction, Negishi reaction and Kumada reaction is exemplified.

In the above-mentioned polymerization method, as a method of charging the monomer, a method of charging the entire amount of the monomer in a batch, a method of charging a part of the monomer and reacting, and then collectively charging the remaining monomer. Examples thereof include a method of continuously or separately charging, a method of continuously or dividing the monomer, and the like.

Examples of the transition metal catalyst include a palladium catalyst, a nickel catalyst and the like.

The post-treatment of the polymerization reaction is carried out by a known method, for example, a method of removing water-soluble impurities by liquid separation, a reaction solution after the polymerization reaction is added to a lower alcohol such as methanol, the precipitated precipitate is filtered, and then dried. The method of making the mixture is used alone or in combination. When the purity of the cross-linking group-containing polymer compound of the first organic layer is low, it can be purified by a usual method such as recrystallization, reprecipitation, continuous extraction with a Soxhlet extractor, or column chromatography.

<Phosphorescent transition metal complex>
The phosphorescent transition metal complex contained in the first organic layer of the light emitting device according to one aspect of the present invention will be described.

The "phosphorescent transition metal complex" usually means a compound that exhibits phosphorescence at room temperature (25 ° C.), and is preferably a metal complex that exhibits light emission from a triplet excited state at room temperature. The metal complex exhibiting light emission from this triplet excited state has a central metal atom and a ligand.

Examples of the central metal atom include a metal atom having an atom number of 40 or more, which has a spin-orbit interaction when formed into a complex and can cause an intersystem crossing between a singlet state and a triplet state. Be done. Examples of the metal atom include a ruthenium atom, a rhodium atom, a palladium atom, an iridium atom and a platinum atom. Since the luminous efficiency of the light emitting device is more excellent, it is preferably an iridium atom or a platinum atom, and more preferably an iridium atom.

Examples of the ligand include a ligand that forms at least one bond selected from the group consisting of a coordination bond and a covalent bond with the central metal atom. Examples of the bond between the central metal atom and the ligand include a metal-nitrogen bond, a metal-carbon bond, a metal-oxygen bond, a metal-phosphorus bond, a metal-sulfur bond and a metal-halogen bond. Examples of the ligand include a neutral or anionic monodentate ligand and a neutral or anionic polydentate ligand. The polydentate ligand usually means a ligand of 2 or more and 6 or less.

The phosphorescent transition metal complex is preferably a metal complex represented by the formula (2) because the luminous efficiency of the light emitting device is more excellent.

［式（２）中、Ｍは、前記と同じ意味を表す。
ｎ¹は１以上の整数を表し、ｎ²は０以上の整数を表す。但し、Ｍがルテニウム原子、ロジウム原子又はイリジウム原子の場合、ｎ¹＋ｎ²は３であり、Ｍがパラジウム原子又は白金原子の場合、ｎ¹＋ｎ²は２である。
Ｅ¹及びＥ²は、それぞれ独立に、炭素原子又は窒素原子を表す。但し、Ｅ¹及びＥ²の少なくとも一方は炭素原子である。Ｅ¹及びＥ²が複数存在する場合、それらはそれぞれ同一でも異なっていてもよい。
環Ｌ¹は、芳香族複素環を表し、この環は置換基を有していてもよい。前記置換基が複数存在する場合、複数の置換基が互いに結合して、それぞれが結合する原子とともに環を形成していてもよい。環Ｌ¹が複数存在する場合、それらは同一でも異なっていてもよい。
環Ｌ²は、芳香族炭化水素環又は芳香族複素環を表し、これらの環は置換基を有していてもよい。前記置換基が複数存在する場合、複数の置換基が互いに結合して、それぞれが結合する原子とともに環を形成していてもよい。環Ｌ²が複数存在する場合、それらは同一でも異なっていてもよい。
環Ｌ¹が有していてもよい置換基と、環Ｌ²が有していてもよい置換基とは、互いに結合して、それぞれが結合する原子とともに環を形成していてもよい。
Ａ¹−Ｇ¹−Ａ²は、アニオン性の２座配位子を表す。Ａ¹及びＡ²は、それぞれ独立に、炭素原子、酸素原子又は窒素原子を表し、これらの原子は環を構成する原子であってもよい。Ｇ¹は、単結合、又は、Ａ¹及びＡ²とともに２座配位子を構成する原子団を表す。Ａ¹−Ｇ¹−Ａ²が複数存在する場合、それらは同一でも異なっていてもよい。］

[In equation (2), M has the same meaning as described above.
n ¹ represents an integer of 1 or more, and n ² represents an integer of 0 or more. However, when M is a ruthenium atom, a rhodium atom or an iridium atom, n ¹ + n ² is 3, and when M is a palladium atom or a platinum atom, n ¹ + n ² is 2.
E ¹ and E ² independently represent a carbon atom or a nitrogen atom, respectively. However, at least one of E ¹ and E ² is a carbon atom. When there are a plurality of E ¹ and E ² , they may be the same or different from each other.
Ring L ¹ represents an aromatic heterocycle, which ring may have a substituent. When a plurality of the substituents are present, the plurality of substituents may be bonded to each other to form a ring together with the atoms to which they are bonded. If there are multiple rings L ¹ , they may be the same or different.
Ring L ² represents an aromatic hydrocarbon ring or an aromatic heterocycle, and these rings may have a substituent. When a plurality of the substituents are present, the plurality of substituents may be bonded to each other to form a ring together with the atoms to which they are bonded. If there are multiple rings L ² , they may be the same or different.
The substituents that the ring L ¹ may have and the substituents that the ring L ² may have may be bonded to each other to form a ring with the atoms to which they are bonded.
A ¹ −G ¹ −A ² represents an anionic bidentate ligand. A ¹ and A ² independently represent a carbon atom, an oxygen atom, or a nitrogen atom, and these atoms may be atoms constituting a ring. G ¹ represents a single bond or an atomic group constituting a bidentate ligand together with A ¹ and A ² . When there are a plurality of A ^1- G ^1- A ² , they may be the same or different. ]

Since M is more excellent in current luminance efficiency of the light emitting device, it is preferably an iridium atom or a platinum atom, and more preferably an iridium atom. The current luminance efficiency means the luminance (cd / A) per unit current.

When M is a ruthenium atom, a rhodium atom or an iridium atom, n ¹ is preferably 2 or 3, and more preferably 3.
When M is a palladium atom or a platinum atom, n ¹ is preferably 2.
E ¹ and E ² are preferably carbon atoms.

The number of carbon atoms of the aromatic heterocycle represented by ring L ¹ is usually 2 to 60, preferably 3 to 30, and more preferably 4 to 15, excluding the number of carbon atoms of the substituent. is there. Ring L ¹ is preferably a 5-membered aromatic heterocycle or a 6-membered aromatic heterocycle. Ring L ¹ is a 5-membered aromatic heterocycle having 2 or more and 4 or less nitrogen atoms as constituent atoms, or a 6-membered aromatic heterocycle having 1 or more and 4 or less nitrogen atoms as constituent atoms. Is more preferable. These rings may have substituents. However, when ring L ¹ is a 6-membered aromatic heterocycle, E ¹ is preferably a carbon atom.

Examples of the ring L ¹ include a diazole ring, a triazole ring, a tetrazole ring, a pyridine ring, a diazabenzene ring, a triazine ring, an azanaphthalene ring and a diazanaphthalene ring, and preferably a pyridine ring, a diazabenzene ring and an azanaphthalene ring. , A diazanaphthalene ring, a triazole ring or a diazole ring, more preferably a pyridine ring, a diazabenzene ring, an azanaphthalene ring, a diazanaphthalene ring, and even more preferably a pyridine ring, a quinoline ring or an isoquinoline ring. These rings may have substituents.

The number of carbon atoms of the aromatic hydrocarbon ring represented by ring L ² is usually 6 to 60, preferably 6 to 30, and more preferably 6 to 18 without including the number of carbon atoms of the substituent. Is. Examples of the aromatic hydrocarbon ring represented by ring L ² include a benzene ring, a naphthalene ring, an inden ring, a fluorene ring, a phenanthrene ring, a dihydrophenanthrene ring, and a ring in which two or more and five or less of these rings are condensed. Since the external quantum efficiency of the light emitting element is more excellent, a benzene ring, a naphthalene ring, a fluorene ring, a phenanthrene ring or a dihydrophenanthrene ring is preferable, a benzene ring, a fluorene ring or a dihydrophenanthrene ring is more preferable, and a benzene ring is further preferable. These rings may have substituents.

The number of carbon atoms of the aromatic heterocycle represented by ring L ² is usually 2 to 60, not including the number of carbon atoms of the substituent. Examples of the aromatic heterocycle represented by ring L ² include a pyrrole ring, a diazole ring, a furan ring, a thiophene ring, a pyridine ring, a diazabenzene ring, and a ring in which one or more and five or less aromatic rings are condensed. Be done. These rings may have substituents.

Ring L ² is preferably a benzene ring, a fluorene ring, a dihydrophenanthrene ring, a pyridine ring, a diazabenzene ring, a carbazole ring, a dibenzofuran ring or a dibenzothiophene ring, because the external quantum efficiency of the light emitting element is further excellent. It is more preferably a pyridine ring or a diazabenzene ring, and even more preferably a benzene ring. These rings may have substituents.

The substituents that the ring L ¹ and the ring L ² may have include an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, an aryloxy group, a monovalent heterocyclic group, and a substituted amino group. Alternatively, it is preferably a halogen atom, more preferably an alkyl group, a cycloalkyl group, an aryl group, a monovalent heterocyclic group or a substituted amino group, and an alkyl group, an aryl group or a monovalent heterocyclic group. More preferably, it is an aryl group or a monovalent heterocyclic group. These groups may further have substituents.

Since the current luminance efficiency of the light emitting device is more excellent, it is preferable that at least one of the ring L ¹ and the ring L ² has a substituent in the metal complex represented by the formula (2).

As the aryl group in the substituent which the ring L ¹ and the ring L ² may have, a phenyl group, a naphthyl group, a fenthenyl group, a dihydrofenthrenyl group or a fluorenyl group is preferable. The aryl group in the substituents that the ring L ¹ and the ring L ² may have is more preferably a phenyl group or a fluorenyl group, and even more preferably a phenyl group. These groups may have substituents.

Examples of the monovalent heterocyclic group in the substituents that the ring L ¹ and the ring L ² may have include a pyridyl group, a pyrimidinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a dibenzofuranyl group and a dibenzothienyl group. Carbazolyl group, azacarbazolyl group, diazacarbazolyl group, phenoxadinyl group or phenothiazinyl group is preferable, pyridyl group, pyrimidinyl group, triazinyl group, dibenzofuranyl group, dibenzothienyl group or carbazolyl group is more preferable, pyridyl group, pyrimidinyl group. A group or a triazineyl group is more preferable, and a triazinyl group is particularly preferable. These groups may have substituents.

The substituents that the ring L ¹ and the ring L ² may have may further include an alkyl group, a cycloalkyl group, an aryl group, a monovalent heterocyclic group or a substituted amino group. It is preferably an alkyl group, a cycloalkyl group or an aryl group, and even more preferably an alkyl group. These groups may further have substituents.

The aryl group and the monovalent heterocyclic group or the substituted amino group in the substituents that the ring L ¹ and the ring L ² may have are, for example, the formula (DA1) because the external quantum efficiency of the light emitting element is more excellent. )-Formula (DA5) or formula (D-B1) -formula (D-B3), preferably formula (DA1), formula (DA3)-formula (D) -A5) or a group represented by the formula (D-B1) is more preferable, and the group is represented by the formula (DA1), the formula (DA3) or the formula (DA5). Is more preferable, and it is particularly preferable that the group is represented by the formula (DA1) or the formula (DA3).

［式中、Ｒ^p1〜Ｒ^p4は、それぞれ独立に、アルキル基、シクロアルキル基、アルコキシ基、シクロアルコキシ基又はハロゲン原子を表す。Ｒ^p1、Ｒ^p2及びＲ^p4が複数存在する場合、それらはそれぞれ同一であっても異なっていてもよい。
ｎｐ１は、０〜５の整数を表し、ｎｐ２は０〜３の整数を表し、ｎｐ３は０又は１を表し、ｎｐ４は０〜４の整数を表す。ｎｐ１及びｎｐ２が複数ある場合、それらはそれぞれ同一でも異なっていてもよい。］

[In the formula, R ^{p1 to} R ^p4 independently represent an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group or a halogen atom. When a plurality of R ^p1 , R ^p2, and R ^p4 exist, they may be the same or different from each other.
np1 represents an integer from 0 to 5, np2 represents an integer from 0 to 3, np3 represents 0 or 1, and np4 represents an integer from 0 to 4. When there are a plurality of np1 and np2, they may be the same or different from each other. ]

When there are a plurality of substituents that the ring L ¹ may have, it is preferable that they are bonded to each other and do not form a ring with the atoms to which each is bonded. When there are a plurality of substituents that the ring L ² may have, it is preferable that they are bonded to each other and do not form a ring with the atoms to which each is bonded. It is preferable that the substituents that the ring L ¹ may have and the substituents that the ring L ² may have are bonded to each other and do not form a ring with the atoms to which they are bonded.

[Anionic bidentate ligand]
Examples of the anionic bidentate ligand represented by A ¹ −G ¹ −A ² include ligands represented by the formulas (a-101) to (a-109). However, the anionic bidentate ligand represented by A ¹ −G ¹ −A ² is different from the ligand whose number is defined by the subscript n ¹ .

［式（ａ−１０１）〜式（ａ−１０９）中、＊を付した原子は、配位原子を表す。］

[Atoms marked with * in formulas (a-101) to (a-109) represent coordination atoms. ]

The metal complex represented by the formula (2) is preferably the metal complex represented by the formula (1-A) because the luminous efficiency of the light emitting device is more excellent.

Ring L ^1A is preferably a pyridine ring, a quinoline ring, or an isoquinoline ring because the luminous efficiency of the light emitting device is more excellent. These rings may have substituents.

The examples and preferred ranges of substituents that ring L ^1A may have are the same as the examples and preferred ranges of substituents that rings L ¹ and ring L ² may have.

When there are a plurality of substituents that the ring L ^1A may have, it is preferable that they bond with each other and do not form a ring with the atoms to which each bond.

Ring L ^2A is preferably a benzene ring.
E ^{21A to} E ^24A are preferably carbon atoms.

R ^{21A to} R ^24A are preferably hydrogen atoms, alkyl groups or aryl groups because the external quantum efficiency of the light emitting device is more excellent. These groups other than the hydrogen atom may have a substituent.

R ^21A and R ^24A are more preferably hydrogen atoms. R ^22A is more preferably an aryl group which may have a hydrogen atom or a substituent. R ^23A is more preferably an alkyl group which may have a hydrogen atom or a substituent.

In the metal complex represented by the formula (1-A), at least one of the rings L ^1A has a substituent or at least one of R ^{21A to} R ^24A is an alkyl group because the light emitting efficiency of the light emitting element is more excellent. , Cycloalkyl group, alkoxy group, cycloalkoxy group, aryl group, aryloxy group, monovalent heterocyclic group, substituted amino group or halogen atom.

Light emitting element when at least one of R ^{21A to} R ^24A is an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, an aryloxy group, a monovalent heterocyclic group, a substituted amino group or a halogen atom. At least one of R ^22A and R ^23A is an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, an aryloxy group, a monovalent heterocyclic group, a substituted amino group, because the external quantum efficiency of Alternatively, it is preferably a halogen atom, and more preferably an alkyl group, a cycloalkyl group, an aryl group, a monovalent heterocyclic group or a substituted amino group. These groups may have substituents.

Examples and preferred ranges of aryl groups, monovalent heterocyclic groups and substituted amino groups in R ^{21A to} R ^24A are aryl groups and monovalent groups in the substituents that ring L ¹ and ring L ² may have, respectively. It is the same as the example and preferable range of the heterocyclic group and the substituted amino group of.

Examples of substituents that R ^{21A to} R ^24A may have and a preferable range are examples of substituents that rings L ¹ and ring L ² may have, and examples of substituents that may further have. Same as the preferred range.

R ^21A and R ^22A , R ^22A and R ^23A , R ^23A and R ^24A , and the substituents and R ^21A that ring L ^1A may have are bonded together to form a ring with the atoms to which they are bonded. It is preferable not to form.

The metal complex represented by the formula (1-A) is preferably a metal complex represented by the formulas (1-B1) to (1-B5) because the luminous efficiency of the light emitting device is more excellent. , More preferably the metal complex represented by the above formula (1-B1) to the above formula (1-B3), and further preferably the metal complex represented by the above formula (1-B3).

[Metal complexes represented by formulas (1-B1) to (1-B5)]
R ^{11B to} R ^18B are preferably a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, a monovalent heterocyclic group or a substituted amino group, and more preferably, because the light emitting efficiency of the light emitting element is more excellent. It is a hydrogen atom, an alkyl group, an aryl group or a monovalent heterocyclic group, and these groups other than the hydrogen atom may have a substituent.

R ^11B and R ^{14B to} R ^18B are preferably hydrogen atoms or alkyl groups, and more preferably hydrogen atoms, because they facilitate the synthesis of metal complexes. These groups other than the hydrogen atom may have a substituent.

R ^12B is preferably a hydrogen atom because the luminous efficiency of the light emitting device is further excellent.

R ^13B is preferably a hydrogen atom, an aryl group or a monovalent heterocyclic group because the light emitting efficiency of the light emitting element is further excellent, and these groups other than the hydrogen atom may have a substituent.

Examples and preferred ranges of aryl groups, monovalent heterocyclic groups and substituted amino groups in R ^{11B to} R ^18B are aryl groups and monovalent groups in the substituents that ring L ¹ and ring L ² may have, respectively. It is the same as the example and preferable range of the heterocyclic group and the substituted amino group of.

Examples of substituents that R ^{11B to} R ^18B may have and a preferable range are examples of substituents that rings L ¹ and ring L ² may have, and examples of substituents that may further have. Same as the preferred range.

In formulas (1-B1) to (1-B5), at least one of R ^{11B to} R ^14B , R ^{11B to} R ^18B, and R ^{21A to} R ^24A is an alkyl group because the light emitting efficiency of the light emitting element is more excellent. , Cycloalkyl group, alkoxy group, cycloalkoxy group, aryl group, aryloxy group, monovalent heterocyclic group, substituted amino group or halogen atom, preferably R ^12B , R ^13B , R ^22A and R ^23A . At least one is more preferably an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, an aryloxy group, a monovalent heterocyclic group, a substituted amino group or a halogen atom, and R ^13B , R. It is more preferred that at least one of ^22A and R ^23A is an alkyl group, a cycloalkyl group, an aryl group, a monovalent heterocyclic group or a substituted amino group. These groups may have substituents.

In equations (1-B1) to (1-B5), R ^11B and R ^12B , R ^12B and R ^13B , R ^13B and R ^14B , R ^11B and R ^21A , R ^13B and R ^15B , R ^15B and R ^16B. , R ^16B and R ^17B , R ^17B and R ^18B , R ^18B and R ^21A , R ^11B and R ^18B , R ^14B and R ^15B , and R ^12B and R ^18B are bonded atoms, respectively. It is preferable that the ring is not formed together with.

Examples of the phosphorescent transition metal complex include a metal complex represented by the following formula.

Phosphorescent transition metal complexes are described in Aldrich, Luminescience Technology Corp. , American Dye Source, etc. Phosphorescent transition metal complexes are described in "Journal of the American Chemical Society, Vol. 107, 1431-1432 (1985)", "Journal of the American Chemical Society, Vol. 198", Vol. 2004-530254A, 2008-179617, 2011-105701, 2007-504272, International Publication 2006/121811, 2013-147450, 2014- It can also be produced by a known method described in documents such as 224101.

[Host material]
The first organic layer in one embodiment of the present invention further contains a host material having at least one function selected from the group consisting of hole injecting property, hole transporting property, electron injecting property and electron transporting property. , The luminous efficiency of the light emitting element becomes particularly excellent. In the first organic layer according to one aspect of the present invention, the host material may be contained alone or in combination of two or more.

The content of the phosphorescent transition metal complex contained in the first organic layer is usually 0.05 to 80 parts by mass when the total of the metal complex of the first organic layer and the host material is 100 parts by mass. It is preferably 0.1 to 50 parts by mass, more preferably 0.5 to 40 parts by mass, and further preferably 1 to 10 parts by mass.

Since the energy level (T ₁ ) of the lowest excited triplet state of the host material is excellent in the light emitting efficiency of the light emitting element, the energy level equivalent to T ₁ of the above-mentioned phosphorescent transition metal complex, or the energy level of T ₁ Higher energy levels are preferred.

As the host material, since the light emitting element can be produced by a solution coating process, it is preferable that the host material exhibits solubility in a solvent capable of dissolving the above-mentioned phosphorescent transition metal complex.

Host materials are classified into low molecular weight compounds and high molecular weight compounds.

The low molecular weight compound used as the host material has a carbazole skeleton compound, a triarylamine skeleton compound, a phenanthroline skeleton compound, a triaryltriazine skeleton compound, a azole skeleton compound, and a benzothiophene skeleton. Examples thereof include compounds, compounds having a benzofurene skeleton, compounds having a fluorene skeleton, and compounds having a spirofluorene skeleton. An example of a low molecular weight compound used as a host material is a compound represented by the following formula.

The polymer compound used as the host material (hereinafter referred to as “polymer host”) is preferably a polymer compound containing a structural unit represented by the above formula (Y).

The definition, example, and preferable range of the structural unit represented by the formula (Y) which may be contained in the polymer host may be contained in the above-mentioned crosslink group-containing polymer compound of the first organic layer ( It is the same as the definition, example, and preferable range of the structural unit represented by Y).

The structural unit represented by the formula (Y) in which Ar ^Y1 is an arylene group has a higher luminous efficiency of the light emitting element according to the present embodiment, and therefore is the total of the structural units contained in the polymer host. With respect to the amount, it is preferably 0.5 to 90 mol%, more preferably 30 to 87 mol%, still more preferably 50 to 85 mol%.

The structural unit represented by the formula (Y) in which Ar ^Y1 is a divalent heterocyclic group or a divalent group in which an arylene group and a divalent heterocyclic group are directly bonded is a structural unit. Since the light emitting element according to the present embodiment has excellent charge transportability, it is preferably 0.5 to 40 mol%, more preferably 3 to 30 mol%, based on the total amount of the structural units contained in the polymer host. It is more preferably 5 to 20 mol%.

Only one type of the structural unit represented by the formula (Y) may be contained in the polymer host, or two or more types may be contained.

Since the polymer host has excellent hole transportability, it is preferable that the polymer host further contains a structural unit represented by the formula (X).

The definition, example, preferable range, content, etc. of the structural unit represented by the formula (X) which may be contained in the polymer host includes the above-mentioned crosslink group-containing polymer compound of the first organic layer. It is the same as the definition, example, preferable range, content, etc. of the structural unit represented by the formula (X).

In the polymer host, the structural unit represented by the formula (X) may contain only one type or two or more types.

Examples of the polymer host include the polymer compounds P-9 to P-14 in Table 2.

［表中、ｐ、ｑ、ｒ、ｓ及びｔは、各構成単位のモル比率を示す。ｐ＋ｑ＋ｒ＋ｓ＋ｔ＝１００であり、かつ、１００≧ｐ＋ｑ＋ｒ＋ｓ≧７０である。その他の構成単位とは、式（Ｙ）で表される構成単位、式（Ｘ）で表される構成単位以外の構成単位を意味する。］

[In the table, p, q, r, s and t indicate the molar ratio of each structural unit. p + q + r + s + t = 100, and 100 ≧ p + q + r + s ≧ 70. The other structural unit means a structural unit other than the structural unit represented by the formula (Y) and the structural unit represented by the formula (X). ]

The polymer host may be any of a block copolymer, a random copolymer, an alternating copolymer, a graft copolymer, and other embodiments, but a plurality of kinds of raw material monomers are used together. It is preferably a copolymer obtained by polymerizing.

[Manufacturing method of polymer host]
The polymer host of the first organic layer can be produced by the same method as the above-mentioned method for producing the crosslinked group-containing polymer compound of the first organic layer.

[First composition]
The first organic layer includes a compound having a cross-linking group, a phosphorescent transition metal complex, and the above-mentioned host material, hole transport material, hole injection material, electron transport material, electron injection material, fluorescent compound and the like. The layer may contain a composition containing at least one selected from the group consisting of antioxidants (hereinafter, also referred to as "first composition"). The proportion of the compound having a cross-linking group contained in the first composition is 2 to 10% by mass with respect to the total mass of the first composition.

[Hole transport material]
The hole transport material is classified into a low molecular weight compound and a high molecular weight compound, and is preferably a high molecular weight compound. The hole transport material may have a cross-linking group.
Examples of the polymer compound include polyvinylcarbazole and its derivatives; polyarylene having an aromatic amine structure in its side chain or main chain and its derivatives. The polymer compound may be a compound to which an electron accepting site is bound. Examples of the electron-accepting site include fullerenes, tetrafluorotetracyanoquinodimethane, tetracyanoethylene, trinitrofluorenone and the like. The electron-accepting site is preferably fullerene.
In the first composition, the blending amount of the hole transport material is usually 1 to 400 parts by mass, preferably 1 to 400 parts by mass, when the total of the compound having a cross-linking group and the phosphorescent transition metal complex is 100 parts by mass. Is 5 to 150 parts by mass.
The hole transporting material may be used alone or in combination of two or more.

[Electronic transport material]
Electron transport materials are classified into low molecular weight compounds and high molecular weight compounds. The electron transport material may have a cross-linking group.
Examples of low molecular weight compounds include metal complexes having 8-hydroxyquinoline as a ligand, oxadiazole, anthraquinone dimethane, benzoquinone, naphthoquinone, anthraquinone, tetracyanoanthraquinone dimethane, fluorenone, diphenyldicyanoethylene and diphenoquinone. , And these derivatives.
Examples of the polymer compound include polyphenylene, polyfluorene, and derivatives thereof. The polymeric compound may be metal-doped.
In the first composition, the blending amount of the electron transporting material is usually 1 to 400 parts by mass, preferably 1 to 400 parts by mass, when the total of the compound having a cross-linking group and the phosphorescent transition metal complex is 100 parts by mass. It is 5 to 150 parts by mass.
The electron transport material may be used alone or in combination of two or more.

[Hole injection material and electron injection material]
The hole injection material and the electron injection material are classified into low molecular weight compounds and high molecular weight compounds, respectively. The hole injection material and the electron injection material may have a cross-linking group.
Examples of the low molecular weight compound include metal phthalocyanines such as copper phthalocyanine; carbon; metal oxides such as molybdenum and tungsten; and metal fluorides such as lithium fluoride, sodium fluoride, cesium fluoride and potassium fluoride.
Examples of the polymer compound include polyaniline, polythiophene, polypyrrole, polyphenylene vinylene, polythienylene vinylene, polyquinoline and polyquinoxaline, and derivatives thereof; conductivity of polymers containing an aromatic amine structure in the main chain or side chain. Examples include polypolymers.
In the first composition, the blending amounts of the hole injection material and the electron injection material are usually 1 to 400, respectively, when the total of the compound having a cross-linking group and the phosphorescent transition metal complex is 100 parts by mass. It is a mass portion, preferably 5 to 150 parts by mass.
The electron injection material and the hole injection material may be used alone or in combination of two or more.

[Ion dope]
When the hole injection material or the electron injection material contains a conductive polymer, the electric conductivity of the conductive polymer is preferably 1 × ^10-5 S / cm to 1 × 10 ³ S / cm. In order to keep the electric conductivity of the conductive polymer within such a range, an appropriate amount of ions can be doped into the conductive polymer.
The type of ion to be doped is an anion for a hole injection material and a cation for an electron injection material. Examples of the anion include polystyrene sulfonate ion, alkylbenzene sulfonate ion, and camphor sulfonate ion. Examples of the cation include lithium ion, sodium ion, potassium ion, and tetrabutylammonium ion.
The ions to be doped may be used alone or in combination of two or more.

[Fluorescent compound]
Fluorescent compounds are classified into low molecular weight compounds and high molecular weight compounds. The fluorescent compound may have a cross-linking group.
Examples of the low molecular weight compound include naphthalene and its derivatives, anthracene and its derivatives, and perylene and its derivatives.
Examples of the polymer compound include a phenylene group, a naphthalene diyl group, an anthracendiyl group, a fluorinatedyl group, a phenanthreneyl group, a dihydrophenanthreneyl group, a group represented by the above formula (X), a carbazolediyl group and a phenoki. Examples thereof include polymer compounds containing a sagindiyl group, a phenanthiazinediyl group, a pyrenedyl group and the like.
In the first composition, the blending amount of the fluorescent compound is usually 0.1 to 400 parts by mass when the total of the compound having a cross-linking group and the phosphorescent transition metal complex is 100 parts by mass. , Preferably 5 to 150 parts by mass.
The fluorescent compound may be used alone or in combination of two or more.

[Antioxidant]
The antioxidant may be a compound that is soluble in the same solvent as the compound having a cross-linking group and the phosphorescent transition metal complex and does not inhibit light emission and charge transport. For example, examples of the antioxidant include a phenolic antioxidant and a phosphorus antioxidant.
In the first composition, the blending amount of the antioxidant is usually 0.001 to 10 parts by mass when the total of the compound having a cross-linking group and the phosphorescent transition metal complex is 100 parts by mass.
The antioxidant may be used alone or in combination of two or more.

[First ink]
A composition containing a compound having a cross-linking group, a phosphorescent transition metal complex, and a solvent (hereinafter, also referred to as "first ink") includes a spin coating method, a casting method, a micro gravure coating method, and a gravure. Coating method, bar coating method, roll coating method, wire bar coating method, dip coating method, spray coating method, screen printing method, flexo printing method, offset printing method, inkjet printing method, capillary coating method, nozzle coating method, etc. It can be suitably used for a coating method.

The viscosity of the first ink may be adjusted according to the type of coating method, but when a solution such as an inkjet printing method is applied to a printing method via an ejection device, clogging and flight bending occur during ejection. Since it is difficult, it is preferably 1 to 20 mPa · s at 25 ° C.

The solvent contained in the first ink is preferably a solvent capable of dissolving or uniformly dispersing the solid content in the ink. Examples of the solvent include chlorine-based solvents such as 1,2-dichloroethane, 1,1,2-trichloroethane, chlorobenzene and o-dichlorobenzene; ether solvents such as tetrahydrofuran, dioxane, anisole and 4-methylanisole; toluene, Aromatic hydrocarbon solvents such as xylene, mesitylene, ethylbenzene, n-hexylbenzene, cyclohexylbenzene; cyclohexane, methylcyclohexane, n-pentane, n-hexane, n-heptan, n-octane, n-nonane, n- Aliper hydrocarbon solvents such as decane, n-dodecane and bicyclohexyl; ketone solvents such as acetone, methyl ethyl ketone, cyclohexanone and acetophenone; esters such as ethyl acetate, butyl acetate, ethyl cell solve acetate, methyl benzoate and phenyl acetate System solvent; Polyhydric alcohol solvent such as ethylene glycol, glycerin, 1,2-hexanediol; Alcohol solvent such as isopropyl alcohol and cyclohexanol; Sulfoxide solvent such as dimethyl sulfoxide; N-methyl-2-pyrrolidone, N , N-Dimethylformamide and other amide-based solvents can be mentioned. The solvent may be used alone or in combination of two or more.

In the first ink, the blending amount of the solvent is usually 1000 to 100,000 parts by mass, preferably 1000 parts by mass, when the total of the crosslinkable compound, the phosphorescent transition metal complex and the host material is 100 parts by mass. It is 2000 to 20000 parts by mass.

[Second organic layer]
The second organic layer of the present invention is a crosslinked product of a compound having the same cross-linking group as the compound having the same cross-linking group contained in the first organic layer (hereinafter, "the compound of the second organic layer". It is a layer containing "crosslinked body").

The crosslinked compound of the compound of the second organic layer is obtained by bringing a compound having the same crosslinking group as the compound having the crosslinking group into a crosslinked state by the above-mentioned method, conditions and the like.

[Second composition]
The second organic layer includes a crosslinked product of the compound of the second organic layer, a hole transporting material (however, different from the crosslinked product of the compound of the second organic layer), a hole injection material, and an electron transporting material. The layer may contain a composition (hereinafter, also referred to as "second composition") containing at least one material selected from the group consisting of an electron-injected material, a light-emitting material, and an antioxidant.

Examples and preferred ranges of hole-transporting materials, electron-transporting materials, hole-injecting materials, electron-injecting materials and luminescent materials contained in the second composition are the hole-transporting materials contained in the first composition. Same as the examples and preferred ranges of electron transport materials, hole injection materials, electron injection materials and luminescent materials. In the second composition, the compounding amounts of the hole transporting material, the electron transporting material, the hole injecting material, the electron injecting material, and the light emitting material were each based on 100 parts by mass of the crosslinked compound of the second organic layer. In the case, it is usually 1 to 400 parts by mass, preferably 5 to 150 parts by mass.

The examples and preferred ranges of the antioxidants contained in the second composition are the same as the examples and preferred ranges of antioxidants contained in the first composition. In the second composition, the blending amount of the antioxidant is usually 0.001 to 10 parts by mass when the crosslinked product of the compound of the second organic layer is 100 parts by mass.

Examples of a method for determining whether the component contained in the second organic layer before crosslinking and the compound having a crosslinking group contained in the first organic layer are the same include the following methods. First, a second organic layer is formed on the anode by a wet method, and the second organic layer before the crosslinking reaction is dissolved in a solvent such as toluene, xylene, chloroform, or tetrahydrofuran and separated without undergoing a crosslinking reaction. The separated second organic layer before the cross-linking reaction is analyzed by nuclear magnetic resonance spectroscopy or mass spectrometry to identify that it is the same compound as the compound having a cross-linking group contained in the first organic layer. ..

[Second ink]
The composition containing the compound of the second organic layer and the solvent (hereinafter, also referred to as “second ink”) can be suitably used for the wet method described in the section of the first ink. .. The preferred range of viscosity of the second ink is the same as the preferred range of viscosity of the first ink. The examples and preferred ranges of the solvent contained in the second ink are the same as the examples and preferred ranges of the solvent contained in the first ink.
In the second ink, the amount of the solvent blended is usually 1000 to 100,000 parts by mass, preferably 2000 to 20000 parts by mass, when the compound of the second organic layer is 100 parts by mass.

<Layer structure of light emitting element>
The light emitting device in one aspect of the present invention includes an anode, a cathode, a first organic layer and a second organic layer. As an example, the light emitting element 10 shown in FIG. 1 has a structure in which a cathode 1, a first organic layer 2, a second organic layer 3, and an anode 4 are laminated in this order. The light emitting device according to one aspect of the present invention may have a layer other than the anode, the cathode, the first organic layer and the second organic layer.

In the light emitting device according to one aspect of the present invention, the first organic layer is usually a light emitting layer (hereinafter, referred to as "first light emitting layer").

In the light emitting device according to one aspect of the present invention, the second organic layer is usually a hole transport layer, a second light emitting layer or an electron transport layer. The second organic layer is preferably a hole transport layer or a second light emitting layer. The second organic layer is preferably a hole transport layer.

In the light emitting element according to one aspect of the present invention, the first organic layer and the second organic layer are preferably adjacent to each other because the luminous efficiency of the light emitting element is more excellent.

In the light emitting device according to one aspect of the present invention, the second organic layer is preferably a layer provided between the anode and the first organic layer because the luminous efficiency of the light emitting device is more excellent. The second organic layer is more preferably a hole transport layer or a second light emitting layer provided between the anode and the first organic layer. The second organic layer is more preferably a hole transport layer provided between the anode and the first organic layer.

In the first organic layer of the light emitting device according to one aspect of the present invention, the compound having a cross-linking group and the phosphorescent transition metal complex may be contained alone or in combination of two or more. Good. In the second organic layer of the light emitting device according to one aspect of the present invention, the crosslinked product of the compound of the second organic layer may be contained alone or in combination of two or more.

In the light emitting device according to one aspect of the present invention, when the second organic layer is a hole transport layer provided between the anode and the first organic layer, the light emitting efficiency of the light emitting device is more excellent, so that the anode and the first It is preferable to further have a hole injection layer between the two organic layers. When the second organic layer is a hole transport layer provided between the anode and the first organic layer, the light emitting efficiency of the light emitting element is more excellent, so that electrons can be placed between the cathode and the first organic layer. It is preferable to further have at least one layer of an injection layer and an electron transport layer.

In the light emitting element according to one aspect of the present invention, when the second organic layer is a second light emitting layer provided between the anode and the first organic layer, the light emitting efficiency of the light emitting element is more excellent, so that the light emitting element and the anode are used. It is preferable to further have at least one layer of a hole injection layer and a hole transport layer between the second organic layer. When the second organic layer is a second light emitting layer provided between the anode and the first organic layer, the luminous efficiency of the light emitting element is more excellent, so that between the cathode and the first organic layer, It is preferable to further have at least one layer of an electron injection layer and an electron transport layer.

In the light emitting element according to one aspect of the present invention, when the second organic layer is the second light emitting layer provided between the cathode and the first organic layer, the light emitting efficiency of the light emitting element is more excellent, so that the anode It is preferable to further have at least one layer of a hole injection layer and a hole transport layer between the first organic layer. When the second organic layer is a second light emitting layer provided between the cathode and the first organic layer, the light emitting efficiency of the light emitting element is more excellent, so that between the cathode and the second organic layer, It is preferable to further have at least one layer of an electron injection layer and an electron transport layer.

In the light emitting element according to one aspect of the present invention, when the second organic layer is an electron transport layer provided between the cathode and the first organic layer, the light emitting efficiency of the light emitting element is more excellent, so that the anode and the first It is preferable to further have at least one layer of a hole injection layer and a hole transport layer between the organic layer and the hole. When the second organic layer is an electron transport layer provided between the cathode and the first organic layer, the luminous efficiency of the light emitting device of the present invention is more excellent, and therefore, between the cathode and the second organic layer. , It is preferable to further have an electron injection layer.

Specific layer configurations of the light emitting device in some aspects of the present invention include, for example, the layer configurations represented by (D1) to (D15). The light emitting device in some aspects of the present invention usually has a substrate, but may be laminated from the anode on the substrate or may be laminated from the cathode on the substrate.

(D1) Electron / second light emitting layer (second organic layer) / first light emitting layer (first organic layer) / cathode (D2) anode / hole transport layer (second organic layer) / second 1 light emitting layer (first organic layer) / cathode (D3) anode / hole injection layer / second light emitting layer (second organic layer) / first light emitting layer (first organic layer) / cathode (D4) Electron / hole injection layer / second light emitting layer (second organic layer) / first light emitting layer (first organic layer) / electron transport layer / cathode (D5) anode / hole injection layer / Second light emitting layer (second organic layer) / first light emitting layer (first organic layer) / electron injection layer / cathode (D6) anode / hole injection layer / second light emitting layer (second (Organic layer) / first light emitting layer (first organic layer) / electron transport layer / electron injection layer / cathode (D7) anode / hole injection layer / hole transport layer (second organic layer) / second 1 light emitting layer (first organic layer) / cathode (D8) anode / hole injection layer / hole transport layer (second organic layer) / first light emitting layer (first organic layer) / electron transport Layer / cathode (D9) anode / hole injection layer / hole transport layer (second organic layer) / first light emitting layer (first organic layer) / electron injection layer / cathode (D10) anode / hole Injection layer / hole transport layer (second organic layer) / first light emitting layer (first organic layer) / electron transport layer / electron injection layer / cathode (D11) anode / hole injection layer / hole transport Layer / second light emitting layer (second organic layer) / first light emitting layer (first organic layer) / electron transport layer / electron injection layer / cathode (D12) anode / hole injection layer / hole transport Layer (second organic layer) / first light emitting layer (first organic layer) / second light emitting layer / electron transport layer / electron injection layer / cathode (D13) anode / hole injection layer / hole transport Layer / first light emitting layer (first organic layer) / second light emitting layer (second organic layer) / electron transport layer / electron injection layer / cathode (D14) anode / hole injection layer / hole transport Layer / first light emitting layer (first organic layer) / electron transport layer (second organic layer) / electron injection layer / cathode (D15) anode / hole injection layer / hole transport layer (second organic) Layer) / second light emitting layer / first light emitting layer (first organic layer) / electron transport layer / electron injection layer / cathode

In (D1) to (D15), "/" means that the layers before and after the layer are adjacent to each other and laminated. Specifically, the "second light emitting layer (second organic layer) / first light emitting layer (first organic layer)" refers to the second light emitting layer (second organic layer) and the first. It means that the light emitting layer (first organic layer) of the above is adjacently laminated.

In the light emitting device according to one aspect of the present invention, the anode, the hole injection layer, the hole transport layer, the second light emitting layer, the electron transport layer, the electron injection layer and the cathode are each provided with two or more layers, if necessary. It may have been.
When a plurality of anodes, hole injection layers, hole transport layers, second light emitting layers, electron transport layers, electron injection layers and cathodes are present, they may be the same or different from each other.

The thickness of the anode, the hole injection layer, the hole transport layer, the first light emitting layer, the second light emitting layer, the electron transport layer, the electron injection layer and the cathode is usually 1 nm to 1 μm, preferably 2 nm to 2 nm. It is 500 nm, more preferably 5 nm to 150 nm.
In the light emitting device of the present invention, the order, number, and thickness of the layers to be laminated may be adjusted in consideration of the luminous efficiency, driving voltage, and element life of the light emitting device.

[Second light emitting layer]
The second light emitting layer is usually a second organic layer or a layer containing a light emitting material, and is preferably a layer containing a light emitting material. When the second light emitting layer is a layer containing a light emitting material, examples of the light emitting material contained in the second light emitting layer include a light emitting material that may be contained in the above-mentioned second composition. Be done. The light emitting material contained in the second light emitting layer may be contained alone or in combination of two or more.
When the light emitting device according to one aspect of the present invention has a second light emitting layer, and the hole transport layer and the electron transport layer described later are not the second organic layer, the second light emitting layer is the second light emitting layer. It is preferably an organic layer of.

[Hole transport layer]
The hole transport layer is usually a second organic layer or a layer containing a hole transport material. The hole transport layer is preferably a second organic layer. When the hole transporting layer is a layer containing a hole transporting material, examples of the hole transporting material include a hole transporting material that may be contained in the above-mentioned first composition. The hole transport material contained in the hole transport layer may be contained alone or in combination of two or more.
When the light emitting device in one embodiment of the present invention has a hole transport layer, and the second light emitting layer described above and the electron transport layer described later are not the second organic layer, the hole transport layer is the second. It is preferably an organic layer.

[Electronic transport layer]
The electron transport layer is usually a second organic layer or a layer containing an electron transport material. The electron transport layer is preferably a layer containing an electron transport material. When the electron transporting layer is a layer containing an electron transporting material, examples of the electron transporting material contained in the electron transporting layer include an electron transporting material that may be contained in the above-mentioned first composition. .. The electron transporting material contained in the electron transporting layer may be contained alone or in combination of two or more.
When the light emitting device in one embodiment of the present invention has an electron transport layer, and the above-mentioned second light emitting layer and the above hole transport layer are not the second organic layer, the electron transport layer is the second organic layer. It is preferably a layer.

[Hole injection layer and electron injection layer]
The hole injection layer is a layer containing a hole injection material. Examples of the hole injection material contained in the hole injection layer include a hole injection material that may be contained in the above-mentioned first composition. The hole injection material contained in the hole injection layer may be contained alone or in combination of two or more.
The electron injection layer is a layer containing an electron injection material. Examples of the electron-injecting material contained in the electron-injecting layer include an electron-injecting material that may be contained in the above-mentioned first composition. The electron injection material contained in the electron injection layer may be contained alone or in combination of two or more.

[Substrate / Electrode]
The substrate in the light emitting element may be a substrate that can form electrodes and does not chemically change when the organic layer is formed. The substrate in the light emitting element is, for example, a substrate made of a material such as glass, plastic, or silicon. When using an opaque substrate, it is preferable that the electrode farthest from the substrate is transparent or translucent.

Examples of the material of the anode include a conductive metal oxide and a translucent metal. The material of the anode is indium oxide, zinc oxide, tin oxide; conductive compounds such as indium tin oxide (ITO), indium zinc oxide (ITO); composite of silver, palladium and copper (APC); gold, platinum. , Silver and copper are preferred.

As the material of the cathode, for example, metals such as lithium, sodium, potassium, rubidium, cesium, beryllium, magnesium, calcium, strontium, barium, aluminum, zinc, indium; two or more alloys among them; one of them. Alloys of more than one species with one or more of silver, copper, manganese, titanium, cobalt, nickel, tungsten and tin; as well as graphite and graphite interlayer compounds. Examples of the alloy include magnesium-silver alloy, magnesium-indium alloy, magnesium-aluminum alloy, indium-silver alloy, lithium-aluminum alloy, lithium-magnesium alloy, lithium-indium alloy, and calcium-aluminum alloy.

In the light emitting device according to one aspect of the present invention, at least one of the anode and the cathode is usually transparent or translucent, but it is preferable that the anode is transparent or translucent.

Examples of the method for forming the anode and the cathode include a vacuum deposition method, a sputtering method, an ion plating method, a plating method and a laminating method.

[Manufacturing method of light emitting element]
In the light emitting device according to one aspect of the present invention, as a method for forming each layer such as a first light emitting layer, a second light emitting layer, a hole transport layer, an electron transport layer, a hole injection layer, and an electron injection layer, a small molecule is used. When a compound is used, for example, a vacuum deposition method from a powder, a method by forming a film from a solution or a molten state can be mentioned. When a polymer compound is used, for example, a method of forming a film from a solution or a molten state can be mentioned.

The first light emitting layer, the second light emitting layer, the hole transport layer, the electron transport layer, the hole injection layer and the electron injection layer are the first ink, the second ink, and the above-mentioned light emitting material and holes. It can be formed by a coating method such as a spin coating method or an inkjet printing method using inks containing a transport material, an electron transport material, a hole injection material, and an electron injection material, respectively.

The method for producing a light emitting element according to one aspect of the present invention is a cathode, a first organic layer containing a compound having a cross-linking group and a phosphorescent transition metal complex, and a cross-linked product of the same compound as the compound having the cross-linking group. The ratio of the compound having the second organic layer and the anode containing the above in this order and having the cross-linking group contained in the first organic layer is based on the total mass of the first organic layer. A method for producing a light emitting element, which is 2 to 10% by mass, wherein the first organic layer and the second organic layer are formed by a coating method.

[Use of light emitting element]
The light emitting device of the present invention is useful for, for example, a display and lighting.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

In the examples, the polystyrene-equivalent number average molecular weight (Mn) and the polystyrene-equivalent weight average molecular weight (Mw) of the polymer compound were determined by size exclusion chromatography (SEC) using tetrahydrofuran as the mobile phase. The measurement conditions of SEC are as follows.

The polymer compound to be measured was dissolved in tetrahydrofuran at a concentration of about 0.05% by mass, and 10 μL was injected into SEC. The mobile phase was flowed at a flow rate of 2.0 mL / min. PLgel MIXED-B (manufactured by Polymer Laboratories) was used as a column. A UV-VIS detector (manufactured by Shimadzu Corporation, trade name: SPD-10Avp) was used as the detector.

<Synthesis Example P-1> Synthesis of Polymer Compounds P-1 to P-2 The polymer compound P-1 was synthesized according to the method described in JP-A-2011-105701.
The polymeric compound P-2 was synthesized according to the method described in WO 2009/157430.

<Synthesis Example M1> Synthesis of metal complex M1 The metal complex M1 was synthesized according to the method described in JP-A-2011-105701.

<Comparative Example 1> Fabrication and evaluation of light emitting device CD1 (formation of anode and hole injection layer)
An anode was formed by attaching an ITO film to a glass substrate with a thickness of 45 nm by a sputtering method. A solution of poly (ethylenedioxythiophene) / polystyrene sulfonic acid (H.C. Stark, trade name: CLEVIOS PAI4083) was formed on the anode to a thickness of 65 nm by a spin coating method, and under an air atmosphere. The hole injection layer was formed by heating on a hot plate at 200 ° C. for 10 minutes.

(Formation of second organic layer)
A 0.6 mass% xylene solution of the polymer compound P-1 (hereinafter referred to as “composition P”) was prepared for xylene. Using the composition P, a film was formed on the hole injection layer to a thickness of 20 nm by a spin coating method, and heated on a hot plate at 180 ° C. for 60 minutes in a nitrogen gas atmosphere to obtain a second organic substance. A layer was formed. By this heating, the polymer compound P-1 became a crosslinked product.

(Formation of the first organic layer)
A 1.6% by mass xylene solution (hereinafter referred to as "composition M") of a mixture of the polymer compound P-2 (92.5 parts by mass) and the metal complex M1 (7.5 parts by mass) was prepared. .. Using the composition M, a film is formed on the second organic layer by a spin coating method to a thickness of 80 nm, and the first organic layer is formed by heating at 130 ° C. for 10 minutes in a nitrogen gas atmosphere. did.

(Cathode formation)
The substrate on which the first organic layer is formed is depressurized to 1.0 × 10 ^-4 Pa or less in the vapor deposition machine, and then barium is placed on the first organic layer at about 2 nm and then aluminum at about 80 nm as a cathode. Vapor deposition. After the vapor deposition, the light emitting element D1 was manufactured by sealing with a glass substrate.

(Evaluation of light emitting element)
By applying a voltage to the light emitting element CD1, red EL light emission having a peak at 615 nm was observed. The maximum luminous efficiency of the light emitting element CD1 is 100%.

<Comparative Example 2> Preparation and Evaluation of Light Emitting Element CD2 A 1.6 mass% xylene solution of the polymer compound P-1 (hereinafter referred to as “composition N”) was prepared, and the (first) of Comparative Example 1 was prepared. In the formation of the organic layer), the same as in Comparative Example 1 except that the composition M and the composition N (composition M / composition N = 80% by mass / 20% by mass) were used instead of the composition M. The light emitting element CD2 was produced. In the light emitting device CD2, the polymer compound P-1 contained in the first organic layer was a non-crosslinked body.

By applying a voltage to the light emitting element CD2, EL light emission in which red EL light emission having a peak at 615 nm was observed was observed. When the maximum luminous efficiency of the light emitting element CD1 was 100%, the maximum luminous efficiency of the light emitting element CD2 was 89%.

<Example 1> Fabrication and evaluation of light emitting device D1 In place of the composition M in (formation of the first organic layer) of Comparative Example 1, the composition M and the composition N (composition M / composition N =) A light emitting device D1 was produced in the same manner as in Comparative Example 1 except that 98% by mass / 2% by mass was used. In the light emitting device D1, the polymer compound P-1 contained in the first organic layer was a non-crosslinked body.

By applying a voltage to the light emitting element D1, EL light emission in which red EL light emission having a peak at 615 nm was observed was observed. When the maximum luminous efficiency of the light emitting element CD1 was 100%, the maximum luminous efficiency of the light emitting element D1 was 109%.

<Example 2> Fabrication and evaluation of light emitting device D2 In place of the composition M in (formation of the first organic layer) of Comparative Example 1, the composition M and the composition N (composition M / composition N =) A light emitting device D2 was produced in the same manner as in Comparative Example 1 except that 94% by mass / 6% by mass was used. In the light emitting device D2, the polymer compound P-1 contained in the first organic layer was a non-crosslinked body.

By applying a voltage to the light emitting element D2, EL light emission in which red EL light emission having a peak at 615 nm was observed was observed. When the maximum luminous efficiency of the light emitting element CD1 was 100%, the maximum luminous efficiency of the light emitting element D2 was 106%.

<Example 3> Fabrication and evaluation of light emitting device D3 In place of the composition M in (formation of the first organic layer) of Comparative Example 1, the composition M and the composition N (composition M / composition N =) A light emitting device D3 was produced in the same manner as in Comparative Example 1 except that 92% by mass / 8% by mass) was used. In the light emitting device D3, the polymer compound P-1 contained in the first organic layer was a non-crosslinked body.

By applying a voltage to the light emitting element D3, EL light emission in which red EL light emission having a peak at 615 nm was observed was observed. When the maximum luminous efficiency of the light emitting element CD1 was 100%, the maximum luminous efficiency of the light emitting element D3 was 106%.

<Example 4> Fabrication and evaluation of light emitting device D4 In place of the composition M in (formation of the first organic layer) of Comparative Example 1, the composition M and the composition N (composition M / composition N =) A light emitting device D3 was produced in the same manner as in Comparative Example 1 except that 90% by mass / 10% by mass) was used. In the light emitting device D4, the polymer compound P-1 contained in the first organic layer was a non-crosslinked body.

By applying a voltage to the light emitting element D4, EL light emission in which red EL light emission having a peak at 615 nm was observed was observed. When the maximum luminous efficiency of the light emitting element CD1 was 100%, the maximum luminous efficiency of the light emitting element D4 was 105%.

Table 3 shows the maximum luminous efficiencies of the light emitting elements D1 to D4 and CD2 as relative values when the maximum luminous efficiency of the light emitting element CD1 is 100%.

According to the present invention, it is possible to provide a light emitting element having excellent luminous efficiency.

1 ... Cathode, 2 ... First organic layer, 3 ... Second organic layer, 4 ... Anode, 10 ... Light emitting element.

Claims (7)

A cathode, a first organic layer containing a compound having a cross-linking group and a phosphorescent transition metal complex, a second organic layer containing a cross-linked product of the same compound as the compound having a cross-linking group, and an anode are used. A light emitting element having the compounds in order and having the cross-linking group contained in the first organic layer in an amount of 2 to 10% by mass based on the total mass of the first organic layer. The light emitting device according to claim 1, wherein the compound having a cross-linking group is a compound having at least one cross-linking group selected from the group of cross-linking groups represented by the formulas (XL-1) to (XL-19).

[In formulas (XL-1) to (XL-19), R ^XL represents a methylene group, an oxygen atom or a sulfur atom, and n ^XL represents an integer of 0 to 5. If there are multiple R ^XLs , they may be the same or different. If there are multiple n ^XLs , they may be the same or different. * 1 represents the bonding position. These cross-linking groups may have substituents, and when a plurality of the substituents are present, the plurality of substituents may be bonded to each other to form a ring together with the carbon atom to which each of the cross-linking groups is bonded. ] The light emitting device according to claim 2, wherein the compound having a cross-linking group is a polymer compound having a structural unit represented by the formula (1) or the formula (1').

[In equation (1), nA represents an integer from 0 to 5, and n represents 1 or 2. When there are a plurality of nA, they may be the same or different.
Ar ³ represents an aromatic hydrocarbon group or a heterocyclic group, and these groups may have a substituent.
L ^A is an alkylene group, a cycloalkylene group, an arylene group, a divalent heterocyclic group, the group represented by -NR'-, an oxygen atom or a sulfur atom, these groups other than oxygen and sulfur atoms It may have a substituent. R'represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, and these groups other than the hydrogen atom may have a substituent. If L ^A is plurally present, they may be the same or different.
X represents a cross-linking group selected from the cross-linking group group. When a plurality of X's exist, they may be the same or different. ]

[In equation (1'), mA represents an integer from 0 to 5, m represents an integer from 1 to 4, and c represents an integer from 0 or 1. If there are multiple mAs, they may be the same or different.
Ar ⁵ represents an aromatic hydrocarbon group, a heterocyclic group, or a group in which an aromatic hydrocarbon ring and a heterocycle are directly bonded, and these groups may have a substituent.
Ar ⁴ and Ar ⁶ each independently represent an arylene group or a divalent heterocyclic group, and these groups may have a substituent.
Ar ⁴ , Ar ⁵ and Ar ⁶ each form a ring by directly bonding with a group other than the group bonded to the nitrogen atom to which the group is bonded, or via an oxygen atom or a sulfur atom. You may be.
K ^A is an alkylene group, a cycloalkylene group, an arylene group, a divalent heterocyclic group, -NR '' - group represented by an oxygen atom or a sulfur atom, these groups other than oxygen and sulfur atoms May have a substituent. R ″ represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, and these groups other than the hydrogen atom may have a substituent. If K ^A there are a plurality, they may be the same or different.
X'represents a cross-linking group, a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group selected from the cross-linking group group, and these groups other than the hydrogen atom have a substituent. You may. However, at least one X'is a cross-linking group selected from the cross-linking group group. ] The light emitting device according to any one of claims 1 to 3, wherein the phosphorescent transition metal complex is a metal complex represented by the formula (1-A).

[In formula (1-A), M represents a ruthenium atom, a rhodium atom, a palladium atom, an iridium atom or a platinum atom.
n ¹ represents an integer of 1 or more, and n ² represents an integer of 0 or more. However, when M is a ruthenium atom, a rhodium atom or an iridium atom, n ¹ + n ² is 3, and when M is a palladium atom or a platinum atom, n ¹ + n ² is 2.
E ¹ represents a carbon atom or a nitrogen atom. If there are multiple E ¹ , they may be the same or different.
Ring L ^1A represents a pyridine ring, a diazabenzene ring, an azanaphthalene ring, a diazanaphthalene ring, a triazole ring or a diazole ring, and these rings may have a substituent. When a plurality of the substituents are present, the plurality of substituents may be bonded to each other to form a ring together with the atoms to which they are bonded. If there are multiple rings L ^1A , they may be the same or different.
E ^21A , E ^22A , E ^23A and E ^24A each independently represent a nitrogen atom or a carbon atom. However, the ring L ^2A represents a benzene ring, a pyridine ring or a diazabenzene ring. If E ^21A is a nitrogen atom, then R ^21A does not exist. If E ^22A is a nitrogen atom, then R ^22A does not exist. If E ^23A is a nitrogen atom, then R ^23A does not exist. If E ^24A is a nitrogen atom, then R ^24A does not exist. When a plurality of E ^21A , E ^22A , E ^23A and E ^24A exist, they may be the same or different from each other.
R ^21A , R ^22A , R ^23A and R ^24A are independently hydrogen atom, alkyl group, cycloalkyl group, alkoxy group, cycloalkoxy group, aryl group, aryloxy group, monovalent heterocyclic group and substituted amino. Representing a group or a halogen atom, these groups other than the hydrogen atom may have a substituent. When there are a plurality of R ^21A , R ^22A , R ^23A and R ^24A , they may be the same or different from each other. The substituents R ^21A and R ^22A , R ^22A and R ^23A , R ^23A and R ^24A , and the substituents that ring L ^1A may have and R ^21A may be bonded to each other to form a ring. ..
A ¹ −G ¹ −A ² represents an anionic bidentate ligand. A ¹ and A ² independently represent a carbon atom, an oxygen atom, or a nitrogen atom, and these atoms may be atoms constituting a ring. G ¹ represents a single bond or an atomic group constituting a bidentate ligand together with A ¹ and A ² . When there are a plurality of A ^1- G ^1- A ² , they may be the same or different. ] The metal complex represented by the formula (1-A) is represented by the formula (1-B1), the formula (1-B2), the formula (1-B3), the formula (1-B4) or the formula (1-B5). The light emitting device according to claim 4, which is a represented metal complex.

[In formulas (1-B1) to (1 to B5), M, n ¹ , n ² , R ^21A , R ^22A , R ^23A , R ^24A and A ^1- G ^1- A ² have the same meanings as described above. Represents.
n ¹¹ and n ¹² independently represent 1 or 2, respectively. However, when M is a ruthenium atom, a rhodium atom or an iridium atom, n ¹¹ + n ¹² is 3, and when M is a palladium atom or a platinum atom, n ¹¹ + n ¹² is 2.
R ^11B , R ^12B , R ^13B , R ^14B , R ^15B , R ^16B , R ^17B and R ^18B are independently hydrogen atoms, alkyl groups, cycloalkyl groups, alkoxy groups, cycloalkoxy groups, aryl groups and aryls, respectively. It represents an oxy group, a monovalent heterocyclic group, a substituted amino group or a halogen atom, and these groups other than the hydrogen atom may have a substituent. If there are multiple R ^11B , R ^12B , R ^13B , R ^14B , R ^15B , R ^16B , R ^17B and R ^18B , they may be the same or different.
In formula (1-B1), R ^11B and R ^12B , R ^12B and R ^13B , R ^13B and R ^14B , and R ^11B and R ^21A may be combined to form a ring, respectively. In equation (1-B2), R ^13B and R ^14B , R ^13B and R ^15B , R ^15B and R ^16B , R ^16B and R ^17B , R ^17B and R ^18B , and R ^18B and R ^21A are combined, respectively. May form a ring. In equation (1-B3), R ^11B and R ^12B , R ^12B and R ^13B , R ^13B and R ^14B , R ^11B and R ^21A , R ^13B and R ^15B , R ^15B and R ^16B , R ^16B and R ^17B , R ^17B and R ^18B , and R ^18B and R ^21A may be bonded to each other to form a ring with the atoms to which they are bonded. In equation (1-B4), R ^11B and R ^18B , R ^14B and R ^15B , R ^15B and R ^16B , R ^16B and R ^17B , R ^17B and R ^18B , and R ^11B and R ^21A are combined, respectively. May form a ring. In equation (1-B5), R ^11B and R ^12B , R ^12B and R ^18B , R ^15B and R ^16B , R ^16B and R ^17B , R ^17B and R ^18B , and R ^11B and R ^21A are combined, respectively. May form a ring. ] The light emitting device according to any one of claims 1 to 5, wherein the first organic layer and the second organic layer are in contact with each other. A cathode, a first organic layer containing a compound having a cross-linking group and a phosphorescent transition metal complex, a second organic layer containing a cross-linked product of the same compound as the compound having a cross-linking group, and an anode are used. A method for producing a light emitting element, wherein the proportion of the compound having the cross-linking group contained in the first organic layer is 2 to 10% by mass with respect to the total mass of the first organic layer. A method for manufacturing a light emitting element, wherein the first organic layer and the second organic layer are formed by a coating method.

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