JP2023050132A - Light-emitting element - Google Patents

Abstract

To provide a light-emitting element with excellent external quantum efficiency.SOLUTION: A light-emitting element includes an anode, a cathode, and a first layer and a second layer provided between the anode and the cathode. The first layer is a layer containing at least one kind of a compound (B-1) selected from compounds (B) including a condensed heterocyclic skeleton (b) including a boron atom and a nitrogen atom, and at least one kind of a compound (A-1) selected from compounds expressed by a formula (H-1). The second layer is a layer containing at least one kind of a compound (A-2) selected from the compounds expressed by the formula (H-1) and a cross-linked body of a compound with a cross-linking group.SELECTED DRAWING: None

Description

The present invention relates to light emitting devices.

A light-emitting device such as an organic electroluminescence device can be suitably used for display and lighting applications. For example, Patent Document 1 describes a light-emitting element having a hole-transporting layer formed using only a polymer compound and a light-emitting layer containing compound H1 and compound B1. Further, Patent Document 2 describes a light-emitting element having a layer containing only a crosslinked product of a compound having a crosslinkable group and a layer containing a compound H2 and a compound B1.

WO2019/225483 JP 2020-167149 A

However, the light-emitting device described above does not necessarily have a sufficient external quantum efficiency.
Accordingly, an object of the present invention is to provide a light-emitting device with excellent external quantum efficiency.

The present invention provides the following [1] to [12].

［式中、
Ａｒ^Ｈ１及びＡｒ^Ｈ２は、それぞれ独立に、アリール基、１価の複素環基又は置換アミノ基を表し、これらの基は置換基を有していてもよい。該置換基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く、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。
ｎ^Ｈ１は、０以上の整数を表す。
Ｌ^Ｈ１は、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。該置換基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く、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。Ｌ^Ｈ１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く、それらは互いに、直接結合して、又は、２価の基を介して結合して、環を形成してもよい。
Ａｒ^Ｈ１とＡｒ^Ｈ２とは、直接結合して、又は、２価の基を介して結合して、環を形成してもよい。Ｌ^Ｈ１とＡｒ^Ｈ１とは、直接結合して、又は、２価の基を介して結合して、環を形成してもよい。Ｌ^Ｈ１とＡｒ^Ｈ２とは、直接結合して、又は、２価の基を介して結合して、環を形成してもよい。］
［２］
前記架橋基を有する化合物が、前記架橋基を有する構成単位を含む高分子化合物である、［１］に記載の発光素子。
［３］
前記架橋基を有する構成単位が、式（Ｚ）で表される構成単位又は式（Ｚ’）で表される構成単位である、［２］に記載の発光素子。

［式中、
ｎは１以上の整数を表す。
ｎＡは０以上の整数を表す。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。
Ａｒ^Ｚは、炭化水素基、複素環基、又は、少なくとも１種の炭化水素基と少なくとも１種の複素環基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。該置換基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く、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。
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、－Ｎ（Ｒ’）－で表される基、酸素原子又は硫黄原子を表し、これらの基は置換基を有していてもよい。該置換基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く、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。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、これらの基は置換基を有していてもよい。該置換基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く、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。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。］

［式中、
ｍＡ、ｍ及びｃは、それぞれ独立に、０以上の整数を表す。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。ｍ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。
Ａｒ^５は、炭化水素基、複素環基、又は、少なくとも１種の炭化水素基と少なくとも１種の複素環基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。該置換基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く、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。Ａｒ^５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。
Ａｒ^４及びＡｒ^６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。該置換基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く、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。
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、－Ｎ（Ｒ’’）－で表される基、酸素原子又は硫黄原子を表し、これらの基は置換基を有していてもよい。該置換基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く、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。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、これらの基は置換基を有していてもよい。該置換基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く、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。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、水素原子、架橋基、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、これらの基は置換基を有していてもよい。該置換基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く、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。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。但し、少なくとも１つのＸ’は架橋基である。］
［４］
前記高分子化合物が、式（Ｘ）で表される構成単位及び式（Ｙ）で表される構成単位からなる群より選ばれる少なくとも１種の構成単位を更に含む、［２］又は［３］に記載の発光素子。

［式中、
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。該置換基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く、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。
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、少なくとも１種のアリーレン基と少なくとも１種の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。該置換基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く、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。Ａｒ^Ｘ２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。Ａｒ^Ｘ４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^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、これらの基は置換基を有していてもよい。該置換基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く、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。Ｒ^Ｘ２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^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。］

［式中、Ａｒ^Ｙ１は、アリーレン基、２価の複素環基、又は、少なくとも１種のアリーレン基と少なくとも１種の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。該置換基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く、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。］
［５］
前記架橋基を有する化合物が、式（Ｚ’’）で表される化合物である、［１］に記載の発光素子。

［式中、 ｍ^Ｂ１、ｍ^Ｂ２及びｍ^Ｂ３は、それぞれ独立に、０以上の整数を表す。ｍ^Ｂ１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。ｍ^Ｂ３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。
Ａｒ^７は、炭化水素基、複素環基、又は、少なくとも１種の炭化水素基と少なくとも１種の複素環基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。該置換基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く、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。Ａｒ^７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。
Ｌ^Ｂ１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、－Ｎ（Ｒ’’’）－で表される基、酸素原子又は硫黄原子を表し、これらの基は置換基を有していてもよい。該置換基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く、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。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、これらの基は置換基を有していてもよい。該置換基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く、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。Ｌ^Ｂ１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、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、これらの基は置換基を有していてもよい。該置換基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く、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。複数存在するＸ’’は、同一でも異なっていてもよい。但し、複数存在するＸ’’のうち、少なくとも１つは、架橋基である。］
［６］
前記架橋基が、架橋基Ａ群から選ばれる少なくとも１種の架橋基である、［１］～［５］のいずれかに記載の発光素子。
（架橋基Ａ群）

［式中、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、該置換基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く、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。］
［７］
前記化合物（Ｂ）が、式（１－１）で表される化合物、式（１－２）で表される化合物又は式（１－３）で表される化合物である、［１］～［６］のいずれかに記載の発光素子。

［式中、
Ａｒ^１、Ａｒ^２及びＡｒ^３は、それぞれ独立に、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。該置換基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く、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。
Ｙ^１は、－Ｎ（Ｒｙ）－で表される基を表す。
Ｙ^２及びＹ^３は、それぞれ独立に、単結合、酸素原子、硫黄原子、セレン原子、－Ｎ（Ｒｙ）－で表される基、－Ｂ（Ｒｙ）－で表される基、アルキレン基、シクロアルキレン基、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。該置換基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く、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。
Ｒｙ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、これらの基は置換基を有していてもよい。該置換基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く、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。Ｒｙが複数存在する場合、同一であっても異なっていてもよい。
Ｙ^１とＡｒ^１とは、直接結合して、又は、２価の基を介して結合して、環を形成してもよい。Ｙ^１とＡｒ^２とは、直接結合して、又は、２価の基を介して結合して、環を形成してもよい。Ｙ^２とＡｒ^１とは、直接結合して、又は、２価の基を介して結合して、環を形成してもよい。Ｙ^２とＡｒ^３とは、直接結合して、又は、２価の基を介して結合して、環を形成してもよい。Ｙ^３とＡｒ^２とは、直接結合して、又は、２価の基を介して結合して、環を形成してもよい。Ｙ^３とＡｒ^３とは、直接結合して、又は、２価の基を介して結合して、環を形成してもよい。］
［８］
前記Ｙ^２及び前記Ｙ^３が、酸素原子、硫黄原子又は－Ｎ（Ｒｙ）－で表される基である、［７］に記載の発光素子。
［９］
前記Ｙ^２及び前記Ｙ^３が、－Ｎ（Ｒｙ）－で表される基である、［７］又は［８］に記載の発光素子。
［１０］
前記第１の層が、正孔輸送材料、正孔注入材料、電子輸送材料、電子注入材料、発光材料及び酸化防止剤からなる群より選ばれる少なくとも１種を更に含有する、［１］～［９］のいずれかに記載の発光素子。
［１１］
前記第１の層と前記第２の層とが隣接している、［１］～［１０］のいずれかに記載の発光素子。
［１２］
前記第２の層が、前記陽極及び前記第１の層との間に設けられた層である、［１］～［１１］のいずれかに記載の発光素子。 [1]
A light emitting device having an anode, a cathode, and a first layer and a second layer provided between the anode and the cathode,
The first layer is
at least one compound (B-1) selected from compounds (B) having a condensed heterocyclic skeleton (b) containing a boron atom and a nitrogen atom in the ring;
A layer containing at least one compound (A-1) selected from compounds represented by formula (H-1),
The second layer is
at least one compound (A-2) selected from compounds represented by formula (H-1);
A light-emitting device, which is a layer containing a crosslinked product of a compound having a crosslinkable group.

[In the formula,
Ar ^H1 and Ar ^H2 each independently represent an aryl group, a monovalent heterocyclic group or a substituted amino group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded.
n ^H1 represents an integer of 0 or more.
L ^H1 represents a divalent group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. When multiple L ^H1 are present, they may be the same or different, and they may be directly bonded to each other or bonded via a divalent group to form a ring.
Ar ^H1 and Ar ^H2 may be directly bonded or bonded via a divalent group to form a ring. L ^H1 and Ar ^H1 may be directly bonded or bonded via a divalent group to form a ring. L ^H1 and Ar ^H2 may be directly bonded or bonded via a divalent group to form a ring. ]
[2]
The light-emitting device according to [1], wherein the compound having the crosslinkable group is a polymer compound containing a structural unit having the crosslinkable group.
[3]
The light-emitting device according to [2], wherein the structural unit having the cross-linking group is a structural unit represented by formula (Z) or a structural unit represented by formula (Z').

[In the formula,
n represents an integer of 1 or more.
nA represents an integer of 0 or more. When multiple nAs are present, they may be the same or different.
Ar ^Z represents a hydrocarbon group, a heterocyclic group, or a group in which at least one hydrocarbon group and at least one heterocyclic group are directly bonded, and these groups may have a substituent good. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded.
L ^A represents an alkylene group, a cycloalkylene group, an arylene group, a divalent heterocyclic group, a group represented by -N(R')-, an oxygen atom or a sulfur atom, and these groups have a substituent. You may have When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. R' represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. When multiple L ^A are present, they may be the same or different.
X represents a cross-linking group. When there are multiple X's, they may be the same or different. ]

[In the formula,
mA, m and c each independently represent an integer of 0 or more. When multiple mA are present, they may be the same or different. When there are multiple m's, they may be the same or different.
Ar ⁵ represents a hydrocarbon group, a heterocyclic group, or a group in which at least one hydrocarbon group and at least one heterocyclic group are directly bonded, and these groups may have a substituent good. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. When multiple Ar ⁵ are present, they may be the same or different.
Ar ⁴ and Ar ⁶ each independently represent an arylene group or a divalent heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded.
K ^A represents an alkylene group, a cycloalkylene group, an arylene group, a divalent heterocyclic group, a group represented by -N(R'')-, an oxygen atom or a sulfur atom, and these groups are substituents. may have. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. R'' represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. When multiple K ^A are present, they may be the same or different.
X' represents a hydrogen atom, a bridging group, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. When multiple X' are present, they may be the same or different. However, at least one X' is a bridging group. ]
[4]
[2] or [3], wherein the polymer compound further comprises at least one structural unit selected from the group consisting of structural units represented by formula (X) and structural units represented by formula (Y); The light-emitting device according to .

[In the formula,
a ^X1 and a ^X2 each independently represent an integer of 0 or more.
Ar ^{1 X1} and Ar 2 ^X3 each independently represent an arylene group or a divalent heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded.
Ar ^X2 and Ar ^X4 each independently represent an arylene group, a divalent heterocyclic group, or a divalent group in which at least one arylene group and at least one divalent heterocyclic group are directly bonded; and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. When multiple Ar ^X2 are present, they may be the same or different. When multiple Ar ^X4 are present, they may be the same or different.
R ^X1 , R ^X2 and R ^X3 each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. When multiple R ^X2 are present, they may be the same or different. When multiple R ^X3 are present, they may be the same or different. ]

[Wherein, Ar ^Y represents an arylene group, a divalent heterocyclic group, or a divalent group in which at least one arylene group and at least one divalent heterocyclic group are directly bonded, The group may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. ]
[5]
The light-emitting device according to [1], wherein the compound having a cross-linking group is a compound represented by formula (Z'').

[In the formula, m ^B1 , m ^B2 and m ^B3 each independently represent an integer of 0 or more. When multiple ^mB1 are present, they may be the same or different. When multiple ^mB3 are present, they may be the same or different.
Ar ⁷ represents a hydrocarbon group, a heterocyclic group, or a group in which at least one hydrocarbon group and at least one heterocyclic group are directly bonded, and these groups may have a substituent good. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. When multiple Ar ⁷ are present, they may be the same or different.
L ^B1 represents an alkylene group, a cycloalkylene group, an arylene group, a divalent heterocyclic group, a group represented by -N(R''')-, an oxygen atom or a sulfur atom, and these groups are substituents may have When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. R''' represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. When multiple L ^B1 are present, they may be the same or different.
X'' represents a bridging group, a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. Multiple X'' may be the same or different. However, at least one of the plurality of X'' is a cross-linking group. ]
[6]
The light-emitting device according to any one of [1] to [5], wherein the cross-linking group is at least one cross-linking group selected from Group A of cross-linking groups.
(Crosslinking group A group)

[In the formula, R ^XL represents a methylene group, an oxygen atom or a sulfur atom, and n ^XL represents an integer of 0 to 5. When multiple R ^XL are present, they may be the same or different. When multiple ^nXL are present, they may be the same or different. *1 represents the binding position. These bridging groups may have substituents, and when there are multiple substituents, they may be the same or different, and are bonded to each other to form a ring together with the atoms to which they are bonded. may ]
[7]
The compound (B) is a compound represented by formula (1-1), a compound represented by formula (1-2) or a compound represented by formula (1-3), 6].

[In the formula,
Ar ¹ , Ar ² and Ar ³ each independently represent an aromatic hydrocarbon group or a heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded.
Y ¹ represents a group represented by -N(Ry)-.
Y ² and Y ³ each independently represent a single bond, an oxygen atom, a sulfur atom, a selenium atom, a group represented by -N(Ry)-, a group represented by -B(Ry)-, an alkylene group, It represents a cycloalkylene group, an arylene group or a divalent heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded.
Ry represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. When two or more Ry are present, they may be the same or different.
Y ¹ and Ar ¹ may be directly bonded or bonded via a divalent group to form a ring. Y ¹ and Ar ² may be directly bonded or bonded via a divalent group to form a ring. Y ² and Ar ¹ may be directly bonded or bonded via a divalent group to form a ring. Y ² and Ar ³ may be directly bonded or bonded via a divalent group to form a ring. Y ³ and Ar ² may be directly bonded or bonded via a divalent group to form a ring. Y ³ and Ar ³ may be directly bonded or bonded via a divalent group to form a ring. ]
[8]
The light-emitting device according to [7], wherein the Y ² and the Y ³ are an oxygen atom, a sulfur atom or a group represented by -N(Ry)-.
[9]
The light-emitting device according to [7] or [8], wherein the Y ² and the Y ³ are groups represented by -N(Ry)-.
[10]
The first layer further contains at least one selected from the group consisting of a hole transport material, a hole injection material, an electron transport material, an electron injection material, a light emitting material and an antioxidant, 9].
[11]
The light-emitting device according to any one of [1] to [10], wherein the first layer and the second layer are adjacent to each other.
[12]
The light-emitting device according to any one of [1] to [11], wherein the second layer is a layer provided between the anode and the first layer.

According to the present invention, it is possible to provide a light-emitting device with excellent external quantum efficiency.

Preferred embodiments of the present invention are described in detail below.

<Description of common terms>
Terms commonly used in this specification have the following meanings unless otherwise specified.

"Room temperature" means 25°C.
Me is a methyl group, Et is an ethyl group, Bu is a butyl group, i-Pr is an isopropyl group, and t-Bu is a tert-butyl group.
A hydrogen atom may be a deuterium atom or a protium atom.
In the formulas representing the metal complexes, solid lines representing bonds with the central metal mean ionic bonds, covalent bonds or coordinate bonds.

A "low-molecular-weight compound" means a compound having no molecular weight distribution and a molecular weight of 1×10 ⁴ or less.
A “polymer compound” means a polymer having a molecular weight distribution and a polystyrene-equivalent number average molecular weight of 1×10 ³ or more (for example, 1×10 ³ to 1×10 ⁸ ).
A "structural unit" means a unit that exists at least one in a polymer compound. Two or more structural units present in a polymer compound are generally called "repeating units".
The polymer compound may be a block copolymer, a random copolymer, an alternating copolymer, a graft copolymer, or other forms.
The terminal group of the polymer compound is preferably a stable group because if the polymerization active group remains as it is, there is a possibility that the light-emitting properties, etc., will be lowered when the polymer compound is used for the production of a light-emitting device. . The terminal group of the polymer compound is preferably a group conjugated to the main chain of the polymer compound, for example, an aryl group or 1 valent heterocyclic groups.

The "alkyl group" may be either linear or branched. The number of carbon atoms in the linear alkyl group is generally 1-50, preferably 1-20, more preferably 1-10, not including the number of carbon atoms in the substituents. The number of carbon atoms in the branched alkyl group is usually 3-50, preferably 3-20, more preferably 4-10, not including the number of carbon atoms in the substituent.
The alkyl group may have a substituent. Examples of alkyl groups include methyl group, ethyl group, propyl group, isopropyl group, butyl group, 2-butyl group, isobutyl group, tert-butyl group, pentyl group, isoamyl group, 2-ethylbutyl group, hexyl group and heptyl. octyl, 2-ethylhexyl, 3-propylheptyl, decyl, 3,7-dimethyloctyl, 2-ethyloctyl, 2-hexyldecyl and dodecyl groups. In addition, alkyl groups are groups in which some or all of the hydrogen atoms in these groups are substituted with substituents (e.g., trifluoromethyl group, pentafluoroethyl group, perfluorobutyl group, perfluorohexyl group, perfluorohexyl group, fluorooctyl group, 3-phenylpropyl group, 3-(4-methylphenyl)propyl group, 3-(3,5-di-hexylphenyl)propyl group and 6-ethyloxyhexyl group).
The number of carbon atoms in the "cycloalkyl group" is usually 3-50, preferably 3-20, more preferably 4-10, not including the number of carbon atoms in the substituents.
A cycloalkyl group may have a substituent. Cycloalkyl groups include, for example, cyclohexyl groups and groups in which some or all of the hydrogen atoms in the groups are substituted with substituents.
The number of carbon atoms in the "alkylene group" is generally 1-20, preferably 1-15, more preferably 1-10, not including the number of carbon atoms in the substituents.
The alkylene group may have a substituent. The alkylene group includes, for example, a methylene group, an ethylene group, a propylene group, a butylene group, a hexylene group, an octylene group, and groups in which some or all of the hydrogen atoms in these groups are substituted with substituents.
The number of carbon atoms in the "cycloalkylene group" is usually 3 to 20, preferably 4 to 10, more preferably 5 to 7, not including the number of carbon atoms in substituents.
A cycloalkylene group may have a substituent. The cycloalkylene group includes, for example, a cyclohexylene group and a group in which some or all of the hydrogen atoms in the group are substituted with substituents.

“Aromatic hydrocarbon group” means a group obtained by removing one or more hydrogen atoms directly bonded to carbon atoms constituting a ring from an aromatic hydrocarbon. A group obtained by removing one hydrogen atom directly bonded to a carbon atom constituting a ring from an aromatic hydrocarbon is also referred to as an "aryl group". A group obtained by removing two hydrogen atoms directly bonded to carbon atoms forming a ring from an aromatic hydrocarbon is also referred to as an "arylene group".
The number of carbon atoms in the aromatic hydrocarbon group is generally 6-60, preferably 6-40, more preferably 6-20, not including the number of carbon atoms in the substituents.
The "aromatic hydrocarbon group" includes, for example, monocyclic aromatic hydrocarbons (e.g., benzene), or polycyclic aromatic hydrocarbons (e.g., naphthalene, indene, naphthoquinone, indenone and tetralone; tricyclic aromatic hydrocarbons such as anthracene, phenanthrene, dihydrophenanthrene, fluorene, anthraquinone, phenanthoquinone and fluorenone; benzoanthracene, benzophenanthrene and benzofluorene. tetracyclic aromatic hydrocarbons; pentacyclic aromatic hydrocarbons such as dibenzoanthracene, dibenzophenanthrene, dibenzofluorene, indenofluorene and benzofluoranthene; hexacyclic aromatic hydrocarbons such as spirobifluorene ; and seven-ring aromatic hydrocarbons such as benzospirobifluorene and acenaphthofluoranthene). mentioned. Aromatic hydrocarbon groups include groups in which a plurality of these groups are bonded. The aromatic hydrocarbon group may have a substituent.

An "alkoxy group" may be either linear or branched. The straight-chain alkoxy group usually has 1 to 40 carbon atoms, preferably 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, not including the carbon atoms of the substituents. The number of carbon atoms in the branched alkoxy group is usually 3-40, preferably 3-20, more preferably 4-10, not including the number of carbon atoms in the substituent.
The alkoxy group may have a substituent. Examples of alkoxy groups include methoxy, ethoxy, isopropyloxy, butyloxy, hexyloxy, 2-ethylhexyloxy, 3,7-dimethyloctyloxy, lauryloxy, and hydrogen in these groups. Groups in which some or all of the atoms are substituted with substituents are included.
The number of carbon atoms in the "cycloalkoxy group" is usually 3-40, preferably 3-20, more preferably 4-10, not including the number of carbon atoms in the substituents.
A cycloalkoxy group may have a substituent. Cycloalkoxy groups include, for example, cyclohexyloxy groups and groups in which some or all of the hydrogen atoms in the groups are substituted with substituents.
The number of carbon atoms in the "aryloxy group" is generally 6-60, preferably 6-40, more preferably 6-20, not including the number of carbon atoms in the substituents.
The aryloxy group may have a substituent. Examples of the aryloxy group include phenoxy group, naphthyloxy group, anthracenyloxy group, pyrenyloxy group, and groups in which some or all of the hydrogen atoms in these groups have been substituted with substituents.

A “heterocyclic group” means a group obtained by removing one or more hydrogen atoms directly bonded to atoms (carbon atoms or heteroatoms) constituting a ring from a heterocyclic compound. Among the heterocyclic groups, an "aromatic heterocyclic group", which is a group obtained by removing one or more hydrogen atoms directly bonded to atoms constituting a ring from an aromatic heterocyclic compound, is preferable. A group obtained by removing p hydrogen atoms (p represents an integer of 1 or more) directly bonded to atoms constituting a ring from a heterocyclic compound is also referred to as a "p-valent heterocyclic group". A group obtained by removing p hydrogen atoms directly bonded to atoms constituting a ring from an aromatic heterocyclic compound is also referred to as a "p-valent aromatic heterocyclic group".
Examples of the "aromatic heterocyclic compound" include compounds in which the heterocycle itself exhibits aromaticity, such as azole, thiophene, furan, pyridine, diazabenzene, triazine, azanaphthalene, diazanaphthalene, and carbazole, and phenoxazine. , phenothiazine, benzopyran, and the like, compounds in which an aromatic ring is condensed to a heterocyclic ring, even if the heterocyclic ring itself does not exhibit aromaticity.
The number of carbon atoms in the heterocyclic group is generally 1-60, preferably 2-40, more preferably 3-20, not including the number of carbon atoms in the substituent. The number of heteroatoms in the heterocyclic group, not including the number of heteroatoms in the substituent, is usually 1 to 30, preferably 1 to 10, more preferably 1 to 5, and still more preferably 1 to 3. is.
Heterocyclic groups include, for example, monocyclic heterocyclic compounds such as furan, thiophene, oxadiazole, thiadiazole, pyrrole, diazole, triazole, tetrazole, pyridine, diazabenzene and triazine, or Polycyclic heterocyclic compounds (e.g. azanaphthalene, diazanaphthalene, benzofuran, benzothiophene, indole, azaindole, diazaindole, benzodiazole, benzothiadiazole, benzotriazole, benzothiophene dioxide, benzothiophene oxide and bicyclic heterocyclic compounds such as benzopyranone; dibenzofuran, dibenzothiophene, dibenzothiophene dioxide, dibenzothiophene oxide, dibenzopyranone, dibenzoborol, dibenzosilol, dibenzophosphole, dibenzoselenophene, carbazole, azacarbazole , diazacarbazole, phenoxazine, phenothiazine, 9,10-dihydroacridine, 5,10-dihydrophenazine, acridone, phenazaborine, phenophosphadine, phenoselenazine, phenazacillin, azaanthracene, diazaanthracene, azaphenanthrene and diaza tricyclic heterocyclic compounds such as phenanthrene; tetracyclic heterocyclic compounds such as hexaazatriphenylene, benzocarbazole, azabenzocarbazole, diazabenzocarbazole, benzonaphthofuran and benzonaphthothiophene; dibenzocarbazole, India Pentacyclic heterocyclic compounds such as locarbazole, indenocarbazole, azaindolocarbazole, diazaindolocarbazole, azaindenocarbazole and diazaindenocarbazole; carbazolocarbazole, benzoindolocarbazole and benzoindenocarbazole Hexacyclic heterocyclic compounds such as; and heptacyclic heterocyclic compounds such as dibenzoindolocarbazole and dibenzoindenocarbazole. Groups excluding one or more are included. Heterocyclic groups include groups in which multiple of these groups are bonded. The heterocyclic group may have a substituent.

A "halogen atom" means a fluorine atom, a chlorine atom, a bromine atom or an iodine atom.

The "amino group" may have a substituent, preferably a substituted amino group (that is, a secondary amino group or a tertiary amino group, more preferably a tertiary amino group). Preferred substituents on the amino group are alkyl groups, cycloalkyl groups, aryl groups and monovalent heterocyclic groups, and these groups may further have substituents. When the amino group has a plurality of substituents, they may be the same or different, and may be bonded to each other to form a ring together with the nitrogen atom to which each is bonded.
Substituted amino groups include, for example, dialkylamino groups, dicycloalkylamino groups, diarylamino groups, and groups in which some or all of the hydrogen atoms in these groups have been further substituted with substituents.
Substituted amino groups include, for example, dimethylamino group, diethylamino group, diphenylamino group, bis(methylphenyl)amino group, bis(3,5-di-tert-butylphenyl)amino group, and hydrogen in these groups. Groups in which some or all of the atoms are further substituted with substituents are included.

An "alkenyl group" may be either linear or branched. The straight-chain alkenyl group usually has 2 to 30 carbon atoms, preferably 3 to 20 carbon atoms, more preferably 3 to 10 carbon atoms, not including the carbon atoms of the substituents. The number of carbon atoms in the branched alkenyl group is generally 3-30, preferably 4-20, more preferably 4-10, not including the number of carbon atoms in the substituent.
The number of carbon atoms in the "cycloalkenyl group" is generally 3-30, preferably 4-20, more preferably 5-10, not including the number of carbon atoms in the substituents.
Alkenyl groups and cycloalkenyl groups may have a substituent. Examples of alkenyl groups include vinyl group, 1-propenyl group, 2-butenyl group, 3-butenyl group, 3-pentenyl group, 4-pentenyl group, 1-hexenyl group, 5-hexenyl group, 7-octenyl group, and groups in which some or all of the hydrogen atoms in these groups have been substituted with substituents. The cycloalkenyl group includes, for example, a cyclohexenyl group, a cyclohexadienyl group, a cyclooctatrienyl group, a norbornylenyl group, and groups in which some or all of the hydrogen atoms in these groups are substituted with substituents. .
An "alkynyl group" may be either linear or branched. The number of carbon atoms in the alkynyl group is usually 2-30, preferably 3-10, not including the carbon atoms of the substituents. The number of carbon atoms in the branched alkynyl group is generally 4-30, preferably 4-10, not including the carbon atoms of the substituents.
The number of carbon atoms in the "cycloalkynyl group" is usually 4 to 3, not including the carbon atoms of the substituents.
0, preferably 4-10.
The alkynyl group and cycloalkynyl group may have a substituent. Examples of alkynyl groups include ethynyl, 1-propynyl, 2-propynyl, 2-butynyl, 3-butynyl, 3-pentynyl, 4-pentynyl, 1-hexynyl, 5-hexynyl, and groups in which some or all of the hydrogen atoms in these groups have been substituted with substituents. Cycloalkynyl groups include, for example, cyclooctynyl groups and groups in which some or all of the hydrogen atoms in the groups are substituted with substituents.

A “crosslinking 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. The cross-linking group is preferably at least one cross-linking group selected from Group A of cross-linking groups (that is, at least one group selected from groups represented by formulas (XL-1) to (XL-19)). .

The "substituent" includes, 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, Alkenyl groups, cycloalkenyl groups, alkynyl groups and cycloalkynyl groups are included. A substituent may be a bridging group. In addition, when multiple substituents are present, they may be the same or different. In addition, when there are multiple substituents, they may bond with each other to form a ring together with the atoms to which they are bonded, but preferably do not form a ring.

The "divalent group" includes, for example, an alkylene group, a cycloalkylene group, an arylene group, a divalent heterocyclic group, a group represented by -N(R ⁰ )-, represented by -B(R ⁰ )- group represented by -P(R ⁰ )-, group represented by -(O=)P(R ⁰ )-, group represented by -O-, represented by -S- a group represented by -Se-, a group represented by -S(=O)-, a group represented by -S(=O) ₂ - and a group represented by -C(=O)- are mentioned. A divalent group includes groups in which a plurality of these groups are bonded. A divalent group may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. R ⁰ represents a hydrogen atom or a substituent.
R ⁰ includes, for example, a hydrogen atom, 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, a halogen atom and a cyano group. , preferably a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded.

In this specification, the absolute value of the difference between the energy level of the lowest triplet excited state and the energy level of the lowest singlet excited state (hereinafter also referred to as “ΔE _ST ”) is calculated by the following method. is required. First, the ground state of the compound is structurally optimized by density functional theory at the B3LYP level. At that time, 6-31G* is used as a basis function. Then, using the obtained structurally optimized structure, _ΔEST of the compound is calculated by B3LYP-level time-dependent density functional theory. However, when 6-31G* contains an atom that cannot be used, LANL2DZ is used for that atom. Gaussian09 is used as a quantum chemical calculation program.

<First layer>
In the light-emitting device of the present embodiment, the first layer includes at least one compound (B-1) selected from the compounds (B) and at least one compound selected from the compounds represented by the formula (H-1). It is a layer containing the compound (A-1) of
The first layer may contain one type of compound (B-1) alone, or may contain two or more types. The first layer may contain one type of compound (A-1) alone, or may contain two or more types.

The total content of compound (B-1) and compound (A-1) in the first layer may be within a range in which the function of the first layer is exhibited. The total content of the compound (B-1) and the compound (A-1) in the first layer may be, for example, 1 to 100% by mass based on the total amount of the first layer. is preferably 10 to 100% by mass, more preferably 30 to 100% by mass, even more preferably 50 to 100% by mass, and particularly preferably 70 to 100% by mass. % by mass, particularly preferably 90 to 100% by mass.
The content of the compound (B-1) in the first layer may be within a range in which the function as the first layer is exhibited. The content of the compound (B-1) in the first layer is, for example, 0.01 to 99 when the total content of the compound (B-1) and the compound (A-1) is 100 parts by mass. It is preferably 0.1 to 90 parts by mass, more preferably 0.5 to 70 parts by mass, and still more preferably 1 to 70 parts by mass, because the external quantum efficiency of the light emitting device of the present embodiment is more excellent. 50 parts by mass, particularly preferably 3 to 30 parts by mass, and most preferably 5 to 20 parts by mass.

In the first layer, compound (A-1) preferably physically, chemically or electrically interacts with compound (B-1). This interaction makes it possible, for example, to improve or adjust the emission properties, charge transport properties, or charge injection properties of the light emitting device of this embodiment.
In the light-emitting device of the present embodiment, if the light-emitting material is explained as an example, the compound (A-1) and the compound (B-1) electrically interact, By efficiently transferring electric energy to 1), the compound (B-1) can be caused to emit light more efficiently, and the external quantum efficiency of the light emitting device of this embodiment is more excellent.

From the above point of view, in the first layer, the external quantum efficiency of the light-emitting device of the present embodiment is superior, so the compound (A-1) has hole injection properties, hole transport properties, electron injection properties, and electron transport properties. It is preferable to have at least one function selected from
From the above point of view, if the light-emitting material in the first layer is used as an example, the external quantum efficiency of the light-emitting device of the present embodiment is superior, so the compound (B-1) preferably has light-emitting properties.
From the above viewpoint, in the first layer, the lowest excited singlet state (S ₁ ) possessed by the compound (A-1) is superior in the external quantum efficiency of the light-emitting device of the present embodiment, so the compound (B-1) is preferably a higher energy level than the lowest excited singlet state (S ₁ ) possessed by .
From the above viewpoint, in the first layer, the lowest excited triplet state (T ₁ ) possessed by the compound (A-1) is superior in the external quantum efficiency of the light-emitting device of the present embodiment, so the compound (B-1) is preferably at an energy level higher than the lowest excited triplet state (T ₁ ) of .

The compound (A-1) preferably exhibits solubility in a solvent capable of dissolving the compound (B-1), since the light-emitting device of this embodiment can be produced by a wet method. .

In the first layer, the compound (A-1) is preferably a host material or guest material, preferably a host material.
In the first layer, the compound (B-1) is preferably a host material or guest material, preferably a guest material.

In the light-emitting device of this embodiment, the host material means a material that physically, chemically or electrically interacts with the guest material. This interaction makes it possible, for example, to improve or adjust the emission properties, charge transport properties, or charge injection properties of the light emitting device of this embodiment.
In the light-emitting element of the present embodiment, taking the light-emitting material as an example, the host material and the guest material electrically interact with each other, and electric energy is efficiently transferred from the host material to the guest material. Light can be emitted more efficiently, and the external quantum efficiency of the light-emitting device of this embodiment is superior.

From the above viewpoint, in the light-emitting device of this embodiment, since the external quantum efficiency of the light-emitting device of this embodiment is superior, the host material is selected from hole injection properties, hole transport properties, electron injection properties, and electron transport properties. It preferably has at least one function that is
From the above point of view, if the light-emitting material in the light-emitting device of this embodiment is used as an example, the external quantum efficiency of the light-emitting device of this embodiment is superior, so the guest material preferably has light-emitting properties.
From the above point of view, in the light-emitting device of this embodiment, the lowest excited triplet state (T ₁ ) of the host material has a superior external quantum efficiency of the light-emitting device of this embodiment, so the lowest excited triplet state of the guest material A higher energy level than the state (T ₁ ) is preferred.
From the above point of view, in the light emitting device of this embodiment, the lowest excited singlet state (S ₁ ) of the host material has a higher external quantum efficiency of the light emitting device of this embodiment, so the lowest excited singlet state of the guest material A higher energy level than the state (S ₁ ) is preferred.

In the light-emitting device of this embodiment, when the first layer is a layer containing a host material and a guest material, the total content of the host material and the guest material in the first layer is It is sufficient if it is within the range where the function as In the light emitting device of this embodiment, when the first layer is a layer containing a host material and a guest material, the total content of the host material and the guest material in the first layer is, for example, the first It may be 1 to 100% by mass based on the total amount of the layer, and is preferably 10 to 100% by mass, more preferably 30 to 100% by mass, because the external quantum efficiency of the light emitting device of this embodiment is superior. , more preferably 50 to 100% by mass, particularly preferably 70 to 100% by mass, particularly preferably 90 to 100% by mass.
In the light emitting device of this embodiment, when the first layer is a layer containing a host material and a guest material, the content of the guest material in the first layer is It is acceptable as long as it is within the range of In the light emitting device of the present embodiment, when the first layer is a layer containing a host material and a guest material, the content of the guest material in the first layer is the total content of the host material and the guest material. When the amount is 100 parts by mass, for example, it is 0.01 to 99 parts by mass, and the external quantum efficiency of the light emitting device of this embodiment is more excellent, so it is preferably 0.1 to 90 parts by mass, more preferably. is 0.5 to 70 parts by mass, more preferably 1 to 50 parts by mass, particularly preferably 3 to 30 parts by mass, and most preferably 5 to 20 parts by mass.

The host material preferably exhibits solubility in a solvent capable of dissolving the guest material, since the light-emitting device of this embodiment can be produced by a wet method.

[Compound (B)]
Compound (B) is a compound having a condensed heterocyclic skeleton (b) containing a boron atom and a nitrogen atom in the ring.
In the compound (B), at least one of the nitrogen atoms contained in the condensed heterocyclic skeleton (b) is preferably a nitrogen atom that does not form a double bond. It is more preferable that all of the nitrogen atoms in the group are nitrogen atoms that do not form double bonds.
Compound (B) is preferably a compound containing no transition metal element (that is, a compound composed only of typical elements).

The number of carbon atoms in the condensed heterocyclic skeleton (b) is usually 1 to 60, preferably 5 to 40, more preferably 7 to 35, still more preferably 7 to 35, not including the number of carbon atoms in the substituents. is 10-30, particularly preferably 10-25, most preferably 15-25.
The number of heteroatoms in the condensed heterocyclic skeleton (b) is usually 2 to 30, preferably 2 to 15, more preferably 2 to 10, still more preferably 2 to 10, not including the number of heteroatoms in the substituents. is 2 to 5, particularly preferably 2 or 3.
The number of boron atoms in the condensed heterocyclic skeleton (b) is usually 1 to 10, preferably 1 to 5, more preferably 1 to 3, not including the number of boron atoms in the substituents, and further 1 is preferred.
The number of nitrogen atoms in the condensed heterocyclic skeleton (b) is usually 1 to 20, preferably 1 to 10, more preferably 1 to 5, and still more preferably 1 to 5, not including the number of nitrogen atoms in the substituents. is 1 to 3, particularly preferably 2.

The condensed heterocyclic skeleton (b) preferably contains a boron atom and a nitrogen atom that does not form a double bond in the ring, since the light-emitting device of this embodiment has a more excellent external quantum efficiency.

The condensed heterocyclic skeleton (b) is preferably a 3- to 12-ring condensed heterocyclic skeleton (preferably a 4- to 12-ring condensed heterocyclic skeleton, because the external quantum efficiency of the light-emitting device of the present embodiment is superior, It is more preferably a 5- to 12-ring condensed heterocyclic skeleton.), more preferably a 3- to 10-ring condensed heterocyclic skeleton (preferably a 4- to 10-ring condensed heterocyclic ring skeleton, more preferably 5 ~ 10 cyclic condensed heterocyclic ring skeleton.), more preferably 3 to 8 cyclic condensed heterocyclic ring skeleton (preferably 4 to 8 cyclic condensed heterocyclic ring skeleton, more preferably 5 to 8 cyclic is a condensed heterocyclic ring skeleton), particularly preferably a 3- to 6-ring condensed heterocyclic ring skeleton (preferably a 4- to 6-ring condensed heterocyclic ring skeleton, more preferably a 5- or 6-ring condensed heterocyclic ring skeleton). ), and a pentacyclic condensed heterocyclic skeleton is particularly preferred.

The condensed heterocyclic skeleton (b) can also be referred to as a compound having a heterocyclic group (b') containing the condensed heterocyclic skeleton (b).

The heterocyclic group (b') is a group obtained by removing one or more hydrogen atoms directly bonded to the atoms constituting the ring from a polycyclic heterocyclic compound containing a boron atom and a nitrogen atom in the ring. and the group may have a substituent.
In the heterocyclic group (b′), a polycyclic heterocyclic compound preferably contains a nitrogen atom that does not form a double bond with a boron atom because the external quantum efficiency of the light-emitting device of the present embodiment is superior. It is a polycyclic heterocyclic compound containing in the ring.
In the heterocyclic group (b′), polycyclic heterocyclic compounds are preferably 3- to 12-cyclic heterocyclic compounds (preferably 4 to 12 ring heterocyclic compounds, more preferably 5 to 12 ring heterocyclic compounds.), more preferably 3 to 10 ring heterocyclic compounds (preferably 4 to It is a 10-ring heterocyclic compound, more preferably a 5- to 10-ring heterocyclic compound.), more preferably a 3- to 8-ring heterocyclic compound (preferably 4-8 a cyclic heterocyclic compound, more preferably a 5- to 8-ring heterocyclic compound.), particularly preferably a 3- to 6-ring heterocyclic compound (preferably a 4- to 6-ring is a heterocyclic compound of the formula, more preferably a 5- or 6-ring heterocyclic compound), particularly preferably a pentacyclic heterocyclic compound.

Examples of substituents that the heterocyclic group (b′) may have include halogen atoms, cyano groups, alkyl groups, cycloalkyl groups, alkoxy groups, cycloalkoxy groups, aryloxy groups, aryl groups, monovalent heterocyclic groups. A cyclic group or a substituted amino group is preferable, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, a monovalent heterocyclic group or a substituted amino group is more preferable, an alkyl group, a cycloalkyl group, an aryl group, A monovalent heterocyclic group or a substituted amino group is more preferred, and an alkyl group, cycloalkyl group or aryl group is particularly preferred, and these groups may further have a substituent.

The aryl group in the substituent optionally possessed by the heterocyclic group (b′) is preferably a monocyclic or bicyclic to hexacyclic aromatic hydrocarbon to an atom constituting the ring. A group excluding one directly bonded hydrogen atom, more preferably a monocyclic, bicyclic or tricyclic aromatic hydrocarbon in which one hydrogen atom directly bonded to a ring-constituting atom is more preferably benzene, naphthalene, anthracene, phenanthrene or fluorene from which one hydrogen atom directly bonded to a ring-constituting atom has been removed, particularly preferably a phenyl group; The group may have a substituent.
The monovalent heterocyclic group in the substituent that the heterocyclic group (b') may have is preferably a monocyclic or bicyclic to hexacyclic heterocyclic compound, A group in which one hydrogen atom directly bonded to a constituent atom is removed, and one hydrogen atom directly bonded to a ring-constituting atom is removed from a monocyclic, bicyclic or tricyclic heterocyclic compound. more preferably pyridine, diazabenzene, triazine, azanaphthalene, diazanaphthalene, carbazole, dibenzofuran, dibenzothiophene, phenoxazine or phenothiazine, excluding one hydrogen atom directly bonded to a ring-constituting atom groups, particularly preferably carbazole, dibenzofuran, dibenzothiophene, phenoxazine or phenothiazine, excluding one hydrogen atom directly bonded to a ring-constituting atom, particularly preferably carbazole, phenoxazine or It is a group obtained by removing one hydrogen atom directly bonded to an atom constituting a ring from phenothiazine, and these groups may have a substituent. The monovalent heterocyclic group in the substituents optionally possessed by the heterocyclic group (b') is a group obtained by removing one hydrogen atom directly bonded to a ring-constituting atom from pyridine, diazabenzene or triazine. may be present, and the group may have a substituent.
In the substituted amino group in the substituent optionally possessed by the heterocyclic group (b′), the substituent possessed by the amino group is preferably an aryl group or a monovalent heterocyclic group, more preferably an aryl group. The group may further have a substituent. Examples and preferred ranges of the aryl group and the monovalent heterocyclic group in the substituents of the amino group are, respectively, the aryl group and the monovalent heterocyclic ring in the substituents that the heterocyclic group (b') may have It is the same as the example and preferred range of the group.

Substituents which the heterocyclic group (b′) may further have include halogen atoms, cyano groups, alkyl groups, cycloalkyl groups, alkoxy groups, cycloalkoxy groups, aryl An oxy group, an aryl group, a monovalent heterocyclic group or a substituted amino group is preferred, an alkyl group, a cycloalkyl group, an aryl group, a monovalent heterocyclic group or a substituted amino group is more preferred, an alkyl group, a cycloalkyl group or An aryl group is more preferred, and an alkyl group or a cycloalkyl group is particularly preferred. These groups may further have a substituent, but preferably have no further substituent.
Examples and preferred ranges of the aryl group, the monovalent heterocyclic group and the substituted amino group in the substituent that the heterocyclic group (b′) may further have are The same as the examples and preferred ranges of the aryl group, monovalent heterocyclic group and substituted amino group in the substituents that the ring group (b') may have.

A "nitrogen atom that does not form a double bond" means a nitrogen atom that is bonded to three other atoms via single bonds.
"Containing a nitrogen atom that does not form a double bond in the ring" means -N(-R ^N )- (wherein R ^N represents a hydrogen atom or a substituent) or the formula:

で表される基を含むことを意味する。

is meant to contain a group represented by

The compound (B) is preferably a thermally activated delayed fluorescence (TADF) compound because the light emitting device of the present embodiment has a more excellent external quantum efficiency.

_ΔEST of compound (B) may be 2.0 eV or less, 1.5 eV or less, 1.0 eV or less, or 0.80 eV or less, Since the external quantum efficiency of the light-emitting device of this embodiment is superior, it is preferably 0.60 eV or less, more preferably 0.55 eV or less, and even more preferably 0.50 eV or less. _ΔEST of compound (B) may be 0.001 eV or more, 0.01 eV or more, 0.10 eV or more, or 0.20 eV or more. , 0.30 eV or more, or 0.40 eV or more.

Compound (B) is preferably a low-molecular-weight compound.
The molecular weight of compound (B) is preferably 1×10 ² to 5×10 ³ , more preferably 2×10 ² to 3×10 ³ , still more preferably 3×10 ² to 1.5×10 ³ , particularly preferably 4×10 ² to 1×10 ³ .

Compound (B) is a compound represented by formula (1-1), formula (1-2) or formula (1-3), since the light-emitting device of the present embodiment has a more excellent external quantum efficiency. A compound represented by formula (1-2) or formula (1-3) is preferred, and a compound represented by formula (1-2) is even more preferred.

Ar ¹ , Ar ² and Ar ³ are preferably monocyclic or bicyclic to hexacyclic aromatic hydrocarbons or monocyclic Or a group obtained by removing one or more hydrogen atoms directly bonded to the atoms constituting the ring from a bicyclic to hexacyclic heterocyclic compound, more preferably monocyclic, bicyclic or tricyclic A group obtained by removing one or more hydrogen atoms directly bonded to atoms constituting a ring from an aromatic hydrocarbon of the formula or a monocyclic, bicyclic or tricyclic heterocyclic compound, more preferably is a group obtained by removing one or more hydrogen atoms directly bonded to the atoms constituting the ring from a monocyclic aromatic hydrocarbon or a monocyclic heterocyclic compound, particularly preferably benzene, pyridine or A group obtained by removing one or more hydrogen atoms directly bonded to a ring-constituting atom from diazabenzene, and particularly preferably a group obtained by removing one or more hydrogen atoms directly bonded to a ring-constituting atom from benzene. and these groups may have a substituent.
Examples and preferred ranges of substituents that Ar ¹ , Ar ² and Ar ³ may have are the same as examples and preferred ranges of substituents that the heterocyclic group (b′) may have.

Y ² and Y ³ are preferably a single bond, an oxygen atom, a sulfur atom, a selenium atom, a group represented by -N(Ry)-, or - A group represented by B(Ry)-, an alkylene group or a cycloalkylene group, more preferably a single bond, an oxygen atom, a sulfur atom, a group represented by -N(Ry)-, or -B(Ry) A group represented by - or an alkylene group, more preferably an oxygen atom, a sulfur atom, a group represented by -N(Ry)- or an alkylene group, particularly preferably an oxygen atom, a sulfur atom or - A group represented by N(Ry)-, particularly preferably a group represented by -N(Ry)-, and these groups may have a substituent.

The arylene group for Y ² and Y ³ is preferably a group obtained by removing two hydrogen atoms directly bonded to the carbon atoms constituting the ring from a monocyclic or bicyclic to hexacyclic aromatic hydrocarbon. and more preferably a group obtained by removing two hydrogen atoms directly bonded to the carbon atoms constituting the ring from a monocyclic, bicyclic or tricyclic aromatic hydrocarbon, more preferably benzene, naphthalene, anthracene, phenanthrene, dihydrophenanthrene or fluorene from which two hydrogen atoms directly bonded to carbon atoms constituting a ring are removed; particularly preferably, benzene, naphthalene or fluorene constitutes a ring; It is a group excluding two hydrogen atoms directly bonded to a carbon atom, particularly preferably a phenylene group, and these groups may have a substituent.
The divalent heterocyclic group for Y ² and Y ³ is preferably a monocyclic or bicyclic to hexacyclic heterocyclic compound directly bonded to a ring-constituting atom (preferably a carbon atom). A group excluding two hydrogen atoms, more preferably a monocyclic, bicyclic or tricyclic heterocyclic compound, a hydrogen directly bonded to an atom (preferably a carbon atom) constituting a ring A group with two atoms removed, more preferably pyridine, diazabenzene, triazine, azanaphthalene, diazanaphthalene, dibenzofuran, dibenzothiophene, carbazole, azacarbazole, diazacarbazole, phenoxazine, phenothiazine, 9,10- A group obtained by removing two hydrogen atoms directly bonded to ring-constituting atoms (preferably carbon atoms) from dihydroacridine or 5,10-dihydrophenazine, particularly preferably pyridine, diazabenzene, triazine, carbazole, phenoxy a group obtained by removing two hydrogen atoms directly bonded to ring-constituting atoms (preferably carbon atoms) from sazine, phenothiazine, 9,10-dihydroacridine or 5,10-dihydrophenazine, particularly preferably pyridine , diazabenzene or triazine by removing two hydrogen atoms directly bonded to atoms (preferably carbon atoms) constituting the ring, and these groups may have a substituent.
The alkylene group for Y ² and Y ³ is preferably a methylene group, an ethylene group or a propylene group, more preferably a methylene group, and these groups may have a substituent.

Examples and preferred ranges of substituents that Y ¹ , Y ² and Y ³ may have are the same as examples and preferred ranges of substituents that the heterocyclic group (b′) may have.

Ry is preferably an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, more preferably an aryl group or a monovalent heterocyclic group, still more preferably an aryl group; A group may have a substituent.
Examples and preferred ranges of the aryl group and monovalent heterocyclic group in Ry are respectively examples and preferred examples of the aryl group and monovalent heterocyclic group in the substituent that the heterocyclic group (b′) may have Same as range.
Examples and preferred ranges of substituents that Ry may have are the same as examples and preferred ranges of substituents that the heterocyclic group (b') may have.

Y ¹ and Ar ¹ are directly bonded or bonded via a divalent group to form a ring (for example, a ring containing Y ¹ and Ar ¹ , a boron atom (B), Y ¹ , A ring other than the ring composed of Ar ¹ and Ar ² ) may be formed, but it is preferable not to form a ring because the synthesis of compound (B) is easy.
When Y ¹ and Ar ¹ are bonded through a divalent group to form a ring, the divalent group is preferably an alkylene group, a cycloalkylene group, an arylene group, a divalent hetero a cyclic group, a group represented by -N(R ⁰ )-, a group represented by -B(R ⁰ )-, a group represented by -O-, a group represented by -S- or -Se- and more preferably an alkylene group, a cycloalkylene group, a group represented by -N(R ⁰ )-, a group represented by -B(R ⁰ )-, and a group represented by -O- a group represented by -S- or a group represented by -Se-, more preferably an alkylene group, a group represented by -N(R ⁰ )-, a group represented by -O- or a group represented by -S-, particularly preferably a group represented by -O-, a group represented by -S- or a group represented by -N(R ⁰ )- , particularly preferably a group represented by -N(R ⁰ )-, and these groups may have a substituent.
When Y ¹ and Ar ¹ are bonded via a divalent group to form a ring, examples and preferred ranges of the arylene group, divalent heterocyclic group and alkylene group in the divalent group are They are the same as the examples and preferred ranges of the arylene group, divalent heterocyclic group and alkylene group for ^Y2 and ^Y3 , respectively.
When Y ¹ and Ar ¹ are bonded via a divalent group to form a ring, examples and preferred ranges of substituents that the divalent group may have include Y ² and Y It is the same as the examples and preferred range of the substituent that ³ may have.
When Y ¹ and Ar ¹ are bonded via a divalent group to form a ring, the preferred range of R ⁰ in the divalent group is the same as the preferred range of Ry.

Y ¹ and Ar ² are directly bonded or bonded via a divalent group to form a ring (for example, a ring containing Y ¹ and Ar ² , a boron atom (B), Y ¹ , A ring other than the ring composed of Ar ¹ and Ar ² ) may be formed, but it is preferable not to form a ring because the synthesis of compound (B) is easy. Examples and preferred ranges of the divalent group when Y ¹ and Ar ² are bonded via a divalent group to form a ring are Y ¹ and Ar ¹ via a divalent group are the same as the examples and preferred ranges of the divalent group in the case of forming a ring by combining with each other.
Y ² and Ar ¹ are directly bonded or bonded via a divalent group to form a ring (for example, a ring containing Y ² and Ar ¹ , a boron atom (B), Y ² , A ring other than the ring composed of Ar ¹ and Ar ³ ) may be formed, but it is preferable not to form a ring because the synthesis of the compound (B) is easy. Examples and preferred ranges of the divalent group when Y ² and Ar ¹ are bonded via a divalent group to form a ring are Y ¹ and Ar ¹ via a divalent group are the same as the examples and preferred ranges of the divalent group in the case of forming a ring by combining with each other.
Y ² and Ar ³ are directly bonded or bonded via a divalent group to form a ring (for example, a ring containing Y ² and Ar ³ , a boron atom (B), Y ² , A ring other than the ring composed of Ar ¹ and Ar ³ ) may be formed, but it is preferable not to form a ring because the synthesis of the compound (B) is easy. Examples and preferred ranges of the divalent group when Y ² and Ar ³ are bonded via a divalent group to form a ring are Y ¹ and Ar ¹ via a divalent group are the same as the examples and preferred ranges of the divalent group in the case of forming a ring by combining with each other.
Y ³ and Ar ² are directly bonded or bonded via a divalent group to form a ring (for example, a ring containing Y ³ and Ar ² , a boron atom (B), Y ³ , A ring other than the ring composed of Ar ² and Ar ³ ) may be formed, but it is preferable not to form a ring because the synthesis of the compound (B) is easy. Examples and preferred ranges of the divalent group when Y ³ and Ar ² are bonded via a divalent group to form a ring are Y ¹ and Ar ¹ via a divalent group are the same as the examples and preferred ranges of the divalent group in the case of forming a ring by combining with each other.
Y ³ and Ar ³ are directly bonded or bonded via a divalent group to form a ring (for example, a ring containing Y ³ and Ar ³ , a boron atom (B), Y ³ , A ring other than the ring composed of Ar ² and Ar ³ ) may be formed, but it is preferable not to form a ring because the synthesis of the compound (B) is easy. Examples and preferred ranges of the divalent group when Y ³ and Ar ³ are bonded via a divalent group to form a ring are Y ¹ and Ar ¹ via a divalent group are the same as the examples and preferred ranges of the divalent group in the case of forming a ring by combining with each other.

Examples of the compound (B) include compounds represented by the following formula and compounds B1 to B5 described later. In the formula, Z ¹ represents an oxygen atom or a sulfur atom. When multiple Z ¹ are present, they may be the same or different.

The maximum peak wavelength of the emission spectrum of compound (B) at 25° C. is preferably 380 nm or longer, more preferably 400 nm or longer, even more preferably 420 nm or longer, and particularly preferably 440 nm or longer. The maximum peak wavelength of the emission spectrum of compound (B) at 25° C. is preferably 750 nm or less, more preferably 620 nm or less, even more preferably 570 nm or less, particularly preferably 495 nm or less, particularly preferably 480 nm or less.
The maximum peak half width of the emission spectrum of compound (B) at 25° C. is preferably 50 nm or less, more preferably 40 nm or less, even more preferably 30 nm or less, and particularly preferably 25 nm or less.
The maximum peak wavelength of the emission spectrum of the compound at room temperature can be determined by dissolving the compound in an organic solvent such as xylene, toluene, chloroform, tetrahydrofuran, etc., and preparing a dilute solution (1×10 ⁻⁶ mass % to 1×10 ⁻³ mass %). %), which can be evaluated by measuring the PL spectrum of the dilute solution at room temperature. Xylene is preferred as the organic solvent for dissolving the compound.

[Compound represented by formula (H-1)]
The compound represented by formula (H-1) is preferably a low-molecular-weight compound.
The molecular weight of the compound represented by formula (H-1) is preferably 1×10 ² to 5×10 ³ , more preferably 2×10 ² to 3×10 ³ , still more preferably 3×10 ² to 1.5×10 ³ , particularly preferably 4×10 ² to 1×10 ³ .
The compound represented by formula (H-1) is preferably a compound different from compound (B), and more preferably a compound that does not have a condensed heterocyclic skeleton (b).

The aryl groups in Ar ^{1 H1} and Ar ^{2 H2} are preferably directly attached to the atoms constituting the ring from monocyclic or bi- to seven-ring aromatic hydrocarbons, because the light-emitting device of this embodiment has superior external quantum efficiency. A group in which one hydrogen atom is removed, more preferably a monocyclic or bi- to five-ring aromatic hydrocarbon group in which one hydrogen atom directly bonded to a ring-constituting atom is removed. and more preferably a monocyclic, bicyclic or tricyclic aromatic hydrocarbon group with one hydrogen atom directly bonded to a ring-constituting atom removed, and these groups have substituents may have.
The aryl groups in Ar ^H1 and Ar ^H2 are preferably benzene, naphthalene, anthracene, phenanthrene, dihydrophenanthrene, fluorene, benzanthracene, benzophenanthrene, benzofluorene, a group obtained by removing one hydrogen atom directly bonded to a ring-constituting atom from dibenzoanthracene, dibenzophenanthrene, dibenzofluorene, indenofluorene or benzofluoranthene, more preferably benzene, naphthalene, anthracene or phenanthrene , dihydrophenanthrene, fluorene, benzoanthracene, benzophenanthrene or benzofluorene, from which one hydrogen atom directly bonded to a ring-constituting atom is removed, more preferably benzene, naphthalene, anthracene, phenanthrene, dihydrophenanthrene or a group obtained by removing one hydrogen atom directly bonded to a ring-constituting atom from fluorene, particularly preferably benzene, naphthalene or anthracene, with one hydrogen atom directly bonded to a ring-constituting atom removed. These groups may have a substituent.

The monovalent heterocyclic group in Ar ^H1 and Ar ^H2 is a group obtained by removing one hydrogen atom directly bonded to a ring-constituting atom from a heterocyclic compound that does not contain a condensed heterocyclic skeleton (b). is preferred, and this group may have a substituent. In the monovalent heterocyclic group for Ar ^H1 and Ar ^H2 , the heterocyclic compound that does not contain a condensed heterocyclic skeleton (b) includes, for example, among the heterocyclic compounds described in the section on the heterocyclic group above, , heterocyclic compounds containing no boron or nitrogen atoms in the ring.
The monovalent heterocyclic groups in Ar ^H1 and Ar ^H2 are preferably monocyclic or di- to hepta-cyclic heterocyclic compounds (preferably A group obtained by removing one hydrogen atom directly bonded to a ring-constituting atom from a monocyclic or 2- to 7-ring heterocyclic compound that does not contain a condensed heterocyclic skeleton (b), more preferably , a monocyclic or bi- to pentacyclic heterocyclic compound (preferably a monocyclic or bi- to pentacyclic heterocyclic compound containing no condensed heterocyclic skeleton (b)). A group excluding one hydrogen atom directly bonded to an atom, more preferably a monocyclic, bicyclic or tricyclic heterocyclic compound (preferably not containing a condensed heterocyclic skeleton (b) , a monocyclic, bicyclic or tricyclic heterocyclic compound) by removing one hydrogen atom directly bonded to an atom constituting the ring, particularly preferably a tricyclic heterocyclic compound A group obtained by removing one hydrogen atom directly bonded to a ring-constituting atom from a compound (preferably a tricyclic heterocyclic compound that does not contain a condensed heterocyclic skeleton (b)), and these groups are It may have a substituent.
The monovalent heterocyclic groups in Ar ^H1 and Ar ^H2 are preferably furan, thiophene, oxadiazole, thiadiazole, pyrrole, diazole, triazole, pyridine, diazabenzene, triazine, azanaphthalene, diazanaphthalene, benzofuran, benzothiophene, indole, azaindole, diazaindole, benzodiazole, benzothiadiazole, benzotriazole, dibenzofuran, dibenzothiophene, carbazole, azacarbazole, diazacarbazole, phenoxy Sajin, phenothiazine, 9,10-dihydroacridine, 5,10-dihydrophenazine, azaanthracene, diazaanthracene, azaphenanthrene, diazaphenanthrene, benzocarbazole, azabenzocarbazole, diazabenzocarbazole, benzonaphthofuran, benzonaphtho thiophene, dibenzocarbazole, indolocarbazole, indenocarbazole, azaindolocarbazole, diazaindolocarbazole, azaindenocarbazole or diazaindenocarbazole from which one hydrogen atom directly bonded to a ring-constituting atom is removed more preferably pyridine, diazabenzene, triazine, azanaphthalene, diazanaphthalene, dibenzofuran, dibenzothiophene, carbazole, azacarbazole, diazacarbazole, phenoxazine, phenothiazine, 9,10-dihydroacridine, 5,10 - dihydrophenazine, benzocarbazole, azabenzocarbazole, diazabenzocarbazole, benzonaphthofuran, benzonaphthothiophene, dibenzocarbazole, indolocarbazole, indenocarbazole, azaindolocarbazole, diazaindolocarbazole, azaindenocarbazole or a group obtained by removing one hydrogen atom directly bonded to a ring-constituting atom from diazaindenocarbazole, more preferably pyridine, diazabenzene, triazine, azanaphthalene, diazanaphthalene, dibenzofuran, dibenzothiophene, carbazole, azacarbazole, diazacarbazole, phenoxazine, phenothiazine, 9,10-dihydroacridine or 5,10-dihydrophenazine with one hydrogen atom directly bonded to a ring-constituting atom removed, particularly preferably A group obtained by removing one hydrogen atom directly bonded to a ring-constituting atom from pyridine, diazabenzene, triazine, azanaphthalene, diazanaphthalene, dibenzofuran, dibenzothiophene or carbazole, particularly preferably dibenzofuran, dibenzothiophene or carbazole is a group obtained by removing one hydrogen atom directly bonded to an atom constituting a ring from , and these groups may have a substituent.

In the substituted amino group for Ar ^H1 and Ar ^H2 , the substituent possessed by the amino group is preferably an aryl group or a monovalent heterocyclic group, more preferably an aryl group, and these groups further have a substituent. good too. Examples and preferred ranges of the aryl group, which is a substituent of the amino group, are the same as the examples and preferred ranges of the aryl group in Ar ^H1 and Ar ^H2 . Examples and preferred ranges of the monovalent heterocyclic group which is a substituent of the amino group are the same as the examples and preferred range of the monovalent heterocyclic group in Ar ^{1 H1} and Ar ^{2 H2} .

At least one of Ar ^H1 and Ar ^H2 is preferably an aryl group or a monovalent heterocyclic group, and both Ar ^H1 and Ar ^H2 are An aryl group or a monovalent heterocyclic group is more preferable, and these groups may have a substituent.
Ar ^H1 and Ar ^H2 are monocyclic, bicyclic or tricyclic aromatic hydrocarbons, or monocyclic, bicyclic or tricyclic aromatic hydrocarbons, since the light-emitting device of this embodiment has superior external quantum efficiency. From a cyclic heterocyclic compound (preferably a monocyclic, bicyclic or tricyclic heterocyclic compound that does not contain a condensed heterocyclic skeleton (b)), it is directly bonded to a ring-constituting atom. A group having one hydrogen atom removed is preferable, and is directly bonded to an atom constituting a ring from benzene, naphthalene, fluorene, pyridine, diazabenzene, triazine, azanaphthalene, diazanaphthalene, dibenzofuran, dibenzothiophene, or carbazole. It is more preferably a group having one hydrogen atom removed, more preferably a phenyl group, a naphthyl group, a fluorenyl group, a carbazolyl group, a dibenzothienyl group or a dibenzofuryl group, and a phenyl group, a naphthyl group or a carbazolyl group. is particularly preferred, and these groups may have a substituent.

The substituents that Ar ^H1 and Ar ^H2 may have are preferably a halogen atom, a cyano group, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryloxy group, an aryl group, and a monovalent A heterocyclic group or a substituted amino group, more preferably an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, a monovalent heterocyclic group or a substituted amino group, still more preferably an alkyl group , a cycloalkyl group, an aryl group, a monovalent heterocyclic group or a substituted amino group, particularly preferably an alkyl group, a cycloalkyl group or an aryl group, even if these groups further have a substituent good.
Examples and preferred ranges of the aryl group, monovalent heterocyclic group and substituted amino group in the substituents that Ar ^H1 and Ar ^H2 may have are the aryl group and monovalent heterocyclic group in Ar ^H1 and Ar ^H2 , respectively. It is the same as the examples and preferred ranges of the cyclic group and the substituted amino group.

Preferred substituents that the substituents Ar ^H1 and Ar ^H2 may further have include a halogen atom, a cyano group, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryloxy group, an aryl group, a monovalent heterocyclic group or a substituted amino group, more preferably an alkyl group, a cycloalkyl group, an aryl group, a monovalent heterocyclic group or a substituted amino group, still more preferably , an alkyl group, a cycloalkyl group or an aryl group, particularly preferably an alkyl group or a cycloalkyl group, and these groups may further have a substituent, but should not have a further substituent. is preferred.
Examples and preferred ranges of the aryl group, monovalent heterocyclic group and substituted amino group in the substituents which the substituents which Ar ^H1 and Ar ^H2 may further have are respectively Ar ^H1 and The same as the examples and preferred ranges of the aryl group, monovalent heterocyclic group and substituted amino group in Ar ^H2 .

The divalent group for L ^H1 is preferably an alkylene group, a cycloalkylene group, an arylene group, a divalent heterocyclic group, —N(R ⁰ )—, —(O=)P(R ⁰ )—, —O—, —S—, —S(=O) ₂ a group represented by - or a group represented by -C(=O)-, more preferably an alkylene group, a cycloalkylene group, an arylene group, a divalent heterocyclic group, or -N(R ⁰ )- A group represented by -O- or a group represented by -S-, more preferably an alkylene group, a cycloalkylene group, an arylene group or a divalent heterocyclic group, particularly An arylene group or a divalent heterocyclic group is preferable, and these groups may have a substituent.
At least one of the divalent groups in L ^H1 is preferably an alkylene group, a cycloalkylene group, an arylene group, or a divalent heterocyclic group, since the light-emitting device of the present embodiment has a superior external quantum efficiency, More preferably, it is an arylene group or a divalent heterocyclic group, and these groups may have a substituent.

Among the divalent groups in L ^H1 , the arylene group preferably forms a ring from a monocyclic or bi- to seven-ring aromatic hydrocarbon because the light-emitting device of the present embodiment has superior external quantum efficiency. A group excluding two hydrogen atoms directly bonded to an atom, more preferably a monocyclic or bi- to five-cyclic aromatic hydrocarbon excluding two hydrogen atoms directly bonded to a ring-constituting atom and more preferably a monocyclic, bicyclic or tricyclic aromatic hydrocarbon group from which two hydrogen atoms directly bonded to atoms constituting the ring are removed, and these groups are It may have a substituent.
Among the divalent groups in L ^H1 , an arylene group is preferably benzene, naphthalene, anthracene, phenanthrene, dihydrophenanthrene, fluorene, benzoanthracene, benzophenanthrene, a group obtained by removing two hydrogen atoms directly bonded to ring-constituting atoms from benzofluorene, dibenzoanthracene, dibenzophenanthrene, dibenzofluorene, indenofluorene or benzofluoranthene, more preferably benzene, naphthalene, a group obtained by removing two hydrogen atoms directly bonded to ring-constituting atoms from anthracene, phenanthrene, dihydrophenanthrene, fluorene, benzanthracene, benzophenanthrene or benzofluorene, more preferably benzene, naphthalene, anthracene or phenanthrene , dihydrophenanthrene or fluorene from which two hydrogen atoms directly bonded to ring-constituting atoms are removed, and particularly preferably benzene, naphthalene or anthracene, with two hydrogen atoms directly bonded to ring-constituting atoms. These groups may have a substituent.

In the divalent group in L ^H1 , the divalent heterocyclic group is a hydrogen atom directly bonded to a ring-constituting atom (preferably a carbon atom) from a heterocyclic compound that does not contain a condensed heterocyclic skeleton (b). It is preferably a group excluding two, and this group may have a substituent. In the divalent group in L ^H1 , the heterocyclic compound that does not contain a condensed heterocyclic skeleton (b) in the divalent heterocyclic group includes the heterocyclic compounds described in the section on the heterocyclic group above. , heterocyclic compounds containing no boron or nitrogen atoms in the ring.
Among the divalent groups in L ^H1 , the divalent heterocyclic group is preferably a monocyclic or bi- to seven-ring heterocyclic compound ( Preferably, two hydrogen atoms directly bonded to atoms (preferably carbon atoms) constituting the ring from a monocyclic or 2- to 7-ring heterocyclic compound that does not contain a condensed heterocyclic skeleton (b) more preferably a monocyclic or bi- to pentacyclic heterocyclic compound (preferably a monocyclic or bi- to pentacyclic heterocyclic compound that does not contain a condensed heterocyclic skeleton (b) A group obtained by removing two hydrogen atoms directly bonded to atoms (preferably carbon atoms) constituting a ring from a cyclic compound), more preferably a monocyclic, bicyclic or tricyclic heterocyclic A hydrogen directly bonded to an atom (preferably a carbon atom) constituting a ring of a compound (preferably a monocyclic, bicyclic or tricyclic heterocyclic compound that does not contain a condensed heterocyclic skeleton (b)) A group with two atoms removed, particularly preferably a monocyclic or tricyclic heterocyclic compound (preferably a monocyclic or tricyclic heterocyclic compound not containing a condensed heterocyclic skeleton (b) A group obtained by removing two hydrogen atoms directly bonded to atoms (preferably carbon atoms) constituting a ring from a cyclic compound), particularly preferably a tricyclic heterocyclic compound (preferably a condensed heterocyclic ring A group obtained by removing two hydrogen atoms directly bonded to atoms (preferably carbon atoms) constituting the ring from a tricyclic heterocyclic compound not including the skeleton (b), and these groups are substituents may have
Among the divalent groups in L ^H1 , a divalent heterocyclic group is preferably furan, thiophene, oxadiazole, thiadiazole, pyrrole, diazole, or triazole, since the light-emitting device of the present embodiment has a further excellent external quantum efficiency. , pyridine, diazabenzene, triazine, azanaphthalene, diazanaphthalene, benzofuran, benzothiophene, indole, azaindole, diazaindole, benzodiazole, benzothiadiazole, benzotriazole, dibenzofuran, dibenzothiophene, carbazole, azacarbazole, diaza Carbazole, phenoxazine, phenothiazine, 9,10-dihydroacridine, 5,10-dihydrophenazine, azaanthracene, diazaanthracene, azaphenanthrene, diazaphenanthrene, benzocarbazole, azabenzocarbazole, diazabenzocarbazole, benzonaphthofuran , benzonaphthothiophene, dibenzocarbazole, indolocarbazole, indenocarbazole, azaindolocarbazole, diazaindolocarbazole, azaindenocarbazole or diazaindenocarbazole directly to an atom (preferably a carbon atom) constituting a ring. a group with two bonding hydrogen atoms removed, more preferably pyridine, diazabenzene, triazine, azanaphthalene, diazanaphthalene, dibenzofuran, dibenzothiophene, carbazole, azacarbazole, diazacarbazole, phenoxazine, phenothiazine, 9 , 10-dihydroacridine, 5,10-dihydrophenazine, benzocarbazole, azabenzocarbazole, diazabenzocarbazole, benzonaphthofuran, benzonaphthothiophene, dibenzocarbazole, indolocarbazole, indenocarbazole, azaindolocarbazole, di a group obtained by removing two hydrogen atoms directly bonded to ring-constituting atoms (preferably carbon atoms) from zaindrocarbazole, azaindenocarbazole or diazaindenocarbazole, more preferably pyridine, diazabenzene, triazine , azanaphthalene, diazanaphthalene, dibenzofuran, dibenzothiophene, carbazole, azacarbazole, diazacarbazole, phenoxazine, phenothiazine, 9,10-dihydroacridine or 5,10-dihydrophenazine. (preferably a carbon A group excluding two hydrogen atoms directly bonded to an atom), particularly preferably a hydrogen directly bonded to an atom (preferably a carbon atom) constituting a ring from pyridine, diazabenzene, triazine, dibenzofuran, dibenzothiophene or carbazole A group with two atoms removed, particularly more preferably a group with two hydrogen atoms directly bonded to a ring-constituting atom (preferably a carbon atom) from dibenzofuran, dibenzothiophene or carbazole. A group may have a substituent.

In the divalent group for L ^H1 , the alkylene group is preferably a methylene group, an ethylene group or a propylene group, more preferably a methylene group, and these groups may have a substituent.

Examples and preferred ranges of substituents that L ^H1 may have are the same as examples and preferred ranges of substituents that Ar ^H1 and Ar ^H2 may have.

In the divalent group in L ^H1 , R ⁰ is preferably an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, more preferably an aryl group or a monovalent heterocyclic group, An aryl group is more preferable, and these groups may have a substituent.
Examples and preferred ranges of the aryl group and monovalent heterocyclic group for R ⁰ in the divalent group for L ^H1 are the examples and preferred ranges for the aryl group and monovalent heterocyclic group for Ar ^H1 and Ar ^H2 , respectively. is the same as
In the divalent group for L ^H1 , examples and preferred ranges of substituents that R ⁰ may have are the same as examples and preferred ranges of substituents that Ar ^H1 and Ar ^H2 may have. .

n ^H1 is usually an integer of 0 or more and 10 or less, preferably an integer of 0 or more and 7 or less, more preferably an integer of 1 or more and 5 or less, and still more preferably an integer of 1 or more and 3 or less, 1 or 2 is particularly preferred.

Ar ^H1 and Ar ^H2 may be directly bonded or bonded via a divalent group to form a ring, but the compound represented by formula (H-1) is easy to synthesize. Therefore, it is preferred not to form a ring.
When Ar ^H1 and Ar ^H2 are bonded via a divalent group to form a ring, the divalent group is preferably an alkylene group, a cycloalkylene group, an arylene group, a divalent hetero A cyclic group, a group represented by -N(R ⁰ )-, a group represented by -(O=)P(R ⁰ )-, a group represented by -O-, a group represented by -S- , a group represented by -S(=O) ₂ - or a group represented by -C(=O)-, more preferably an alkylene group, a cycloalkylene group, or a group represented by -N(R ⁰ )- a group represented by -O- or a group represented by -S-, more preferably an alkylene group, a group represented by -O- or a group represented by -S- , these groups may have a substituent.
When Ar ^H1 and Ar ^H2 are bonded via a divalent group to form a ring, examples and preferred ranges of the arylene group, divalent heterocyclic group and alkylene group in the divalent group are They are the same as the examples and preferred ranges of the arylene group, divalent heterocyclic group and alkylene group in L ^H1 , respectively.
When Ar ^H1 and Ar ^H2 are bonded through a divalent group to form a ring, examples and preferred ranges of R ⁰ in the divalent group are R ⁰ in the divalent group of L ^H1 is the same as the example and preferred range of
When Ar ^{1 H1} and Ar 2 ^H2 are bonded via a divalent group to form a ring, examples and preferred ranges of substituents that the divalent group may have include Ar ^H1 and Ar It is the same as the example and preferred range of the substituent that ^H2 may have.

L ^{1 H1} and Ar ^{1 H1} may be directly bonded or bonded via a divalent group to form a ring, but the compound represented by formula (H-1) is easy to synthesize. Therefore, it is preferred not to form a ring. Examples and preferred ranges of the divalent group in the case where L ^H1 and Ar ^H1 are bonded via a divalent ^group to form ^a ring are: are the same as the examples and preferred ranges of the divalent group in the case of forming a ring by combining with each other.
L ^H1 and Ar ^H2 may be directly bonded or bonded via a divalent group to form a ring, but the compound represented by formula (H-1) is easily synthesized. Therefore, it is preferred not to form a ring. Examples and preferred ranges of ^{the divalent group in the case where L H1 and Ar H2 are bonded} via a divalent group to form a ^ring are: are the same as the examples and preferred ranges of the divalent group in the case of forming a ring by combining with each other.

Examples of the compound represented by formula (H-1) include compounds represented by the following formula. In the formula, Z ¹ represents an oxygen atom or a sulfur atom. In the formula, Z ² represents a group represented by -CH= or a group represented by -N=. When multiple Z ¹ are present, they may be the same or different. When multiple Z ² are present, they may be the same or different.

[First composition]
The first layer is selected from the group consisting of compound (B-1), compound (A-1), hole-transporting material, hole-injecting material, electron-transporting material, electron-injecting material, light-emitting material and antioxidant. It may be a layer containing a composition (hereinafter also referred to as "first composition") containing at least one selected. However, in the first composition, the hole-transporting material, hole-injecting material, electron-transporting material, electron-injecting material, and light-emitting material are different from the compound (B-1). In the first composition, the hole-transporting material, hole-injecting material, electron-transporting material, electron-injecting material and light-emitting material are different from compound (A-1).
The first composition contains a compound (B-1), a compound (A-1), a hole-transporting material, a hole-injecting material, an electron-transporting material, an electron-injecting material, a light-emitting material, and an antioxidant, respectively, It may be contained individually by 1 type, and may be contained 2 or more types.
Total content of compound (B-1), compound (A-1), hole-transporting material, hole-injecting material, electron-transporting material, electron-injecting material, light-emitting material, and antioxidant in the first composition may be within a range in which the function as the first composition can be exhibited. Total content of compound (B-1), compound (A-1), hole-transporting material, hole-injecting material, electron-transporting material, electron-injecting material, light-emitting material, and antioxidant in the first composition is, for example, based on the total amount of the first composition, may be 1 to 100% by mass, may be 10 to 100% by mass, may be 30 to 100% by mass, more preferably 50 It may be up to 100% by mass, 70 to 100% by mass, or 90 to 100% by mass.

(Hole transport material)
Hole-transporting materials are classified into low-molecular-weight compounds and high-molecular-weight compounds. The hole-transporting material may have a cross-linking group.
Examples of low-molecular-weight compounds include triphenylamine and derivatives thereof, N,N'-di-1-naphthyl-N,N'-diphenylbenzidine (α-NPD), and N,N'-diphenyl-N, Aromatic amine compounds such as N'-di(m-tolyl)benzidine (TPD) can be mentioned.
Polymer compounds include, for example, polyvinylcarbazole and derivatives thereof; polyarylenes and derivatives thereof having aromatic amine structures in side chains or main chains. The polymer compound may be a compound having electron-accepting moieties such as fullerene, tetrafluorotetracyanoquinodimethane, tetracyanoethylene and trinitrofluorenone bound thereto.
When the first composition contains a hole-transporting material, the content of the hole-transporting material is based on the total content of compound (B-1) and compound (A-1) being 100 parts by mass. , usually from 1 to 10,000 parts by mass.
The hole transport materials may be used singly or in combination of two or more.

(Electron 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, anthraquinodimethane, benzoquinone, naphthoquinone, anthraquinone, tetracyanoanthraquinodimethane, fluorenone, diphenyldicyanoethylene and diphenoquinone. , as well as derivatives thereof.
Polymer compounds include, for example, polyphenylene, polyfluorene, and derivatives thereof. The polymeric compounds may be doped with metals.
When the first composition contains an electron-transporting material, the content of the electron-transporting material is usually , 1 to 10,000 parts by mass.
The electron transport materials may be used singly or in combination of two or more.

(Hole injection material and electron injection material)
Hole-injecting materials and electron-injecting materials are classified into low-molecular-weight compounds and high-molecular-weight compounds, respectively. The hole-injecting material and the electron-injecting material may have cross-linking groups.
Examples of low-molecular compounds 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.
Polymer compounds include, for example, polyaniline, polythiophene, polypyrrole, polyphenylene vinylene, polythienylene vinylene, polyquinoline and polyquinoxaline, and derivatives thereof; conductive polymers such as polymers containing an aromatic amine structure in the main chain or side chain; and a flexible polymer.
When the first composition contains a hole-injection material and/or an electron-injection material, the contents of the hole-injection material and the electron-injection material are the compound (B-1) and the compound (A-1), respectively. When the total content of is 100 parts by mass, it is usually 1 to 10000 parts by mass.
Each of the hole injection material and the electron injection material may be used alone or in combination of two or more.

- Ion doping The hole injection material and the electron injection material may be doped with ions. For example, when the hole-injecting material and electron-injecting material comprise a conductive polymer, the electrical conductivity of the conductive polymer is preferably between 1×10 ⁻⁵ S/cm and 1×10 ³ S/cm. The conductive polymer can be doped with an appropriate amount of ions in order to set the electrical conductivity of the conductive polymer within this range.
The types of ions to be doped in the hole injection material and the electron injection material include, for example, anions in the case of hole injection materials and cations in the case of electron injection materials. Anions include, for example, polystyrene sulfonate, alkylbenzene sulfonate, and camphor sulfonate. Cations include, for example, lithium ion, sodium ion, potassium ion and tetrabutylammonium ion.
Ions for doping may be used alone or in combination of two or more.

(Luminous material)
Light-emitting materials are classified into low-molecular-weight compounds and high-molecular-weight compounds. The luminescent material may have a cross-linking group.
Examples of low-molecular-weight compounds include naphthalene and its derivatives, anthracene and its derivatives, perylene and its derivatives, and phosphorescent compounds having iridium, platinum, or europium as a central metal.
Examples of polymer compounds include polymer compounds containing a structural unit represented by formula (Y) described later and/or a structural unit represented by formula (X) described later.
When the first composition contains a light-emitting material, the content of the light-emitting material is usually 1 when the total content of the compound (B-1) and the compound (A-1) is 100 parts by mass. ~10000 parts by mass.
The luminescent materials may be used singly or in combination of two or more.

(Antioxidant)
The antioxidant may be a compound that is soluble in the same solvent as the compound (B-1) and the compound (A-1) and does not inhibit light emission and charge transport. Antioxidants are included.
When the first composition contains an antioxidant, the content of the antioxidant is usually 100 parts by mass when the total content of compound (B-1) and compound (A-1) is , 0.00001 to 10 parts by mass.
Antioxidants may be used alone or in combination of two or more.

[First ink]
The first layer is formed using, for example, a composition containing the compound (B-1), the compound (A-1), and a solvent (hereinafter also referred to as "first ink"). can be done.
The first ink may contain one kind of compound (B-1), compound (A-1) and solvent, respectively, or may contain two or more kinds.
The first ink can be applied, for example, by a spin coating method, a casting method, a micro gravure coating method, a gravure coating method, a bar coating method, a roll coating method, a wire bar coating method, a dip coating method, a spray coating method, a screen printing method, a flexographic It can be suitably used for producing a light emitting device using a wet method such as a printing method, an offset printing method, an inkjet printing method, a capillary coating method, a nozzle coating method and the like.
The viscosity of the first ink may be adjusted according to the type of wet method. The viscosity of the first ink is preferably 1 at 25° C. because, for example, clogging and flight deflection during ejection are unlikely to occur when the solution is applied to a printing method such as an inkjet printing method that passes through an ejection device. ~20 mPa·s.
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 contained in the first ink include chlorine-based solvents, ether-based solvents, aromatic hydrocarbon-based solvents, aliphatic hydrocarbon-based solvents, ketone-based solvents, ester-based solvents, polyhydric alcohol-based solvents, alcohol solvent, sulfoxide solvent, amide solvent and water.
In the first ink, the content of the solvent is usually 1000 to 10000000 parts by mass when the total content of compound (B-1) and compound (A-1) is 100 parts by mass.
A solvent may be used individually by 1 type, or may use 2 or more types together.

The first ink may further contain at least one selected from the group consisting of hole-transporting materials, hole-injecting materials, electron-transporting materials, electron-injecting materials, light-emitting materials, and antioxidants.
The first ink may contain one type of hole transport material, hole injection material, electron transport material, electron injection material, light emitting material, and antioxidant, respectively, or contain two or more types. may have been
Examples and preferred ranges of the hole-transporting material, the electron-transporting material, the hole-injecting material, the electron-injecting material, the light-emitting material, and the antioxidant, which the first ink may further comprise, are described in the first composition, respectively. are the same as the examples and preferred ranges of the hole transport material, electron transport material, hole injection material, electron injection material, light emitting material and antioxidant contained in .
The contents of the hole-transporting material, the electron-transporting material, the hole-injecting material, the electron-injecting material, and the light-emitting material, which the first ink may further contain, are respectively the compound (B-1) and the compound (A- When the total content of 1) is 100 parts by mass, it is usually 1 to 10,000 parts by mass. The content of the antioxidant that the first ink may further contain is usually 0.00001 when the total content of the compound (B-1) and the compound (A-1) is 100 parts by mass. ~10 parts by mass.

<Second layer>
In the light emitting device of the present embodiment, the second layer comprises at least one compound (A-2) selected from compounds represented by formula (H-1), a crosslinked compound of a compound having a crosslinking group, It is a layer containing That is, in the second layer, the compound (A-2) and the crosslinked compound having a crosslinkable group are contained as separate compounds.
Here, the compound (A-2) is preferably a compound containing no cross-linking group. Also, the compound (A-2) is preferably a low-molecular-weight compound.

The example and preferred range of compound (A-2) in the second layer are the same as the example and preferred range of compound (A-1) in the first layer.

The second layer may contain only one type of compound (A-2), or may contain two or more types. The second layer may contain only one type of crosslinked compound of a compound having a crosslinkable group, or may contain two or more types.

The total content of the compound (A-2) and the crosslinked product of the compound having a crosslinkable group in the second layer may be within a range in which the function of the second layer is exhibited. The total content of the compound (A-2) in the second layer and the crosslinked product of the compound having a crosslinkable group may be, for example, 1 to 100% by mass based on the total amount of the second layer. Since the external quantum efficiency of the light emitting device of the embodiment is superior, it is preferably 10 to 100% by mass, more preferably 30 to 100% by mass, still more preferably 50 to 100% by mass, particularly preferably 70% by mass. to 100% by mass, particularly preferably 90 to 100% by mass.
The content of the compound (A-2) in the second layer may be any range as long as the function as the second layer is exhibited. The content of the compound (A-2) in the second layer is, for example, 0.01 when the total content of the compound (A-2) and the crosslinked product of the compound having a crosslinkable group is 100 parts by mass. It is preferably 0.1 to 90 parts by mass, more preferably 0.5 to 70 parts by mass, and still more preferably It is 1 to 50 parts by mass, particularly preferably 3 to 30 parts by mass, particularly preferably 5 to 20 parts by mass.

[Cross-linked product of compound having cross-linking group]
A cross-linked product of a compound having a cross-linking group can be obtained, for example, by cross-linking a compound having a cross-linking group by the method and conditions described later.
The compound having a cross-linking group may be a low-molecular-weight compound having a cross-linking group or a high-molecular-weight compound having a cross-linking group.

In the compound having a cross-linking group, the cross-linking group is preferably selected from the cross-linking group A group because the cross-linking property of the compound having a cross-linking group is superior and the external quantum efficiency of the light-emitting device of the present embodiment is superior. At least one cross-linking group (that is, at least one cross-linking group selected from the cross-linking groups represented by formulas (XL-1) to (XL-19)), more preferably the formula (XL- 1) At least one selected from bridging groups represented by ~ formula (XL-4), formula (XL-7) ~ formula (XL-10) and formula (XL-14) ~ formula (XL-19) a bridging group, more preferably Formula (XL-1), Formula (XL-3), Formula (XL-7), Formula (XL-9), Formula (XL-10) and Formula (XL-16) ~ at least one cross-linking group selected from the cross-linking groups represented by formula (XL-19), particularly preferably formula (XL-1), formula (XL-9), formula (XL-10) and At least one cross-linking group selected from the cross-linking groups represented by formulas (XL-16) to (XL-19), particularly preferably formula (XL-1), formula (XL-16) and formula It is at least one cross-linking group selected from cross-linking groups represented by (XL-17).
In Group A of the cross-linking group, examples and preferred ranges of substituents which the cross-linking group may have are the same as examples and preferred ranges of substituents which the group represented by Ar ^Y1 may have.
The compound having a cross-linking group may contain only one cross-linking group, or may contain two or more cross-linking groups.

(Polymer compound having a cross-linking group)
A polymer compound having a cross-linking group has better cross-linking properties, and the light-emitting device of the present embodiment has a higher external quantum efficiency. It is preferable to include as That is, the polymer compound having a cross-linking group is preferably a polymer compound containing a structural unit having a cross-linking group.
Examples and preferred ranges of the cross-linking group in the polymer compound having a cross-linking group and the structural unit having a cross-linking group are the same as the examples and preferred range of the cross-linking group in the compound having a cross-linking group.
When the polymer compound having a crosslinkable group contains a structural unit having a crosslinkable group, the content of the structural unit having a crosslinkable group may be within a range in which the function of the polymer compound having a crosslinkable group is exhibited. When the polymer compound having a crosslinkable group contains a structural unit having a crosslinkable group, the content of the structural unit having a crosslinkable group is, relative to the total content of the structural units contained in the polymer compound having a crosslinkable group, For example, it is 0.1 to 100 mol%, and the crosslinkability of the polymer compound having a crosslinkable group is more excellent, and the external quantum efficiency of the light emitting device of the present embodiment is more excellent, so it is preferably 1 to 99 mol%. , more preferably 2 to 90 mol %, still more preferably 3 to 70 mol %, and particularly preferably 5 to 50 mol %.
A polymer compound having a cross-linking group may contain only one type of constitutional unit having a cross-linking group, or may contain two or more types thereof.

The structural unit having a cross-linking group is preferably a structural unit represented by formula (Z) or a structural unit represented by formula (Z′), since the light-emitting device of the present embodiment has superior external quantum efficiency. .

Structural unit n represented by formula (Z) is usually an integer of 1 to 10, and is preferably an integer of 1 to 7, more preferably an integer of 1 to 7, because the light-emitting device of the present embodiment has superior external quantum efficiency. is an integer of 1 to 4, more preferably 1 or 2, particularly preferably 2.
nA is usually an integer of 0 to 10, and is preferably an integer of 0 to 7, more preferably an integer of 0 to 4, and still more preferably an integer of 0 to 4, since the light-emitting device of the present embodiment has superior external quantum efficiency. is an integer from 0 to 2.

The hydrocarbon group for Ar ^Z includes an optionally substituted aromatic hydrocarbon group and an optionally substituted aliphatic hydrocarbon group. The hydrocarbon group for Ar ^Z includes groups in which multiple of these groups are bonded.
The aliphatic hydrocarbon group for Ar ^Z includes a group obtained by removing n hydrogen atoms from an alkylene group or a cycloalkylene group, preferably a group obtained by removing n hydrogen atoms from an alkylene group. may have a substituent.
The aromatic hydrocarbon group for Ar ^{2 Z} includes a group obtained by removing n hydrogen atoms from an arylene group, and this group may have a substituent. Examples and preferred ranges of the arylene group include the examples and preferred ranges of the arylene group in Ar ^Y1 described later.
The heterocyclic group for Ar 2 ^Z includes a group obtained by removing n hydrogen atoms from a divalent heterocyclic group, and this group may have a substituent. Examples and preferred ranges of the divalent heterocyclic group include the examples and preferred ranges of the divalent heterocyclic group in Ar ^Y1 described later.
Examples and preferred ranges of the hydrocarbon group and the heterocyclic group in the group in which at least one hydrocarbon group and at least one heterocyclic group in Ar ^Z are directly bonded are the hydrocarbon group and the heterocyclic group in Ar ^Z , respectively. It is the same as the example and preferred range of the cyclic group.
The group in which at least one hydrocarbon group and at least one heterocyclic group are directly bonded in Ar ^Z includes, for example, at least one arylene group and at least one divalent heterocyclic ring in Ar ^Y1 described later. A group obtained by removing n hydrogen atoms from a group to which a group is directly bonded can be mentioned.
Ar ^Z is preferably a hydrocarbon group or a heterocyclic group, more preferably a hydrocarbon group, and still more preferably an aromatic hydrocarbon, since the light-emitting device of the present embodiment has a superior external quantum efficiency. groups, and these groups may have a substituent.

Examples and preferred ranges of the arylene group represented by ^LA include examples and preferred ranges of the arylene group represented by Ar ^Y1 described later. The arylene group represented by ^LA is preferably a phenylene group or a fluorenediyl group because the light-emitting device of the present embodiment has a superior external quantum efficiency, and these groups may have a substituent. good.
Examples and preferred ranges of the divalent heterocyclic group represented by ^LA are the same as examples and preferred ranges of the divalent heterocyclic group represented by Ar ^Y1 described later.
^LA is preferably an arylene group or an alkylene group, more preferably It is a phenylene group, a fluorenediyl group or an alkylene group, and these groups may have a substituent.

R' is preferably an aryl group or a monovalent heterocyclic group, more preferably an aryl group, and these groups may have a substituent.
Examples and preferred ranges of the aryl group and monovalent heterocyclic group for R′ are respectively the examples and preferred range of the aryl group and monovalent heterocyclic group in the substituents Ar ^Y1 may have, which will be described later. are the same.

Examples and preferred ranges of substituents that groups represented by Ar ^Z , ^LA and R′ may have are examples and preferred ranges of substituents that groups represented by Ar ^Y1 may have below. is the same as

Examples and preferred ranges of the cross-linking group for X are the same as the examples and preferred range of the cross-linking group in the compound having a cross-linking group.

Structural unit mA represented by the formula (Z') is usually an integer of 0 to 10, and is preferably an integer of 0 to 7 because the light emitting device of the present embodiment has a higher external quantum efficiency, and more It is preferably an integer of 0 to 4, more preferably an integer of 0 to 2, particularly preferably 0 or 1, and most preferably 0.
m is usually an integer of 0 to 10, and preferably an integer of 0 to 7, more preferably an integer of 0 to 4, and still more preferably an integer of 0 to 4, since the light emitting device of the present embodiment has superior external quantum efficiency. is an integer of 0 to 2, particularly preferably 0.
c is usually an integer of 0 to 10, and is preferably an integer of 0 to 5 because it facilitates synthesis of a polymer compound having a cross-linking group and the external quantum efficiency of the light emitting device of the present embodiment is superior. , more preferably an integer of 0 to 2, still more preferably 0 or 1, and particularly preferably 0.

Examples and preferred ranges of the hydrocarbon group and heterocyclic group for Ar ⁵ are the same as examples and preferred ranges of the hydrocarbon group and heterocyclic group for Ar ^Z , respectively.
Examples and preferred ranges of the group in which at least one hydrocarbon group and at least one heterocyclic group are directly bonded for Ar ⁵ include at least one hydrocarbon group and at least one heterocyclic group for Ar ^Z. is the same as the example and preferred range of the group to which is directly bonded.
Ar ⁵ is preferably a hydrocarbon group or a heterocyclic group, more preferably a hydrocarbon group, and still more preferably an aromatic hydrocarbon, since the light-emitting device of this embodiment has a superior external quantum efficiency. groups, and these groups may have a substituent.

Ar ⁴ and Ar ⁶ are preferably an arylene group optionally having a substituent, since the light-emitting device of this embodiment has a more excellent external quantum efficiency.
Examples and preferred ranges of the arylene groups for Ar ⁴ and Ar ⁶ are the same as the examples and preferred ranges of the arylene groups for Ar ^X1 , Ar ^X2 , Ar ^X3 and Ar ^X4 described later.
Examples and preferred ranges of the divalent heterocyclic group for Ar ⁴ and Ar ⁶ are the same as examples and preferred ranges for the divalent heterocyclic group for Ar ^X1 , Ar ^X2 , Ar ^X3 and Ar ^X4 described later.

Examples and preferred ranges of substituents that groups represented by Ar ⁴ to Ar ⁶ may have are the same as examples and preferred ranges of substituents that groups represented by Ar ^{1 Y1} may have below. is.

The examples and preferred ranges of K ^A are the same as the examples and preferred ranges of L ^A.
The examples and preferred ranges of R'' are the same as the examples and preferred ranges of R'.

Examples and preferred ranges of the cross-linking group for X' are the same as those of the cross-linking group represented by X.
Examples and preferred ranges of the aryl group and the monovalent heterocyclic group for X′ are the examples and preferred ranges of the aryl group and the monovalent heterocyclic group for R ^X1 , R ^X2 and R ^X3 described below, respectively. Same as range.
X' is preferably a bridging group, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, more preferably a bridging group, an aryl group or a monovalent heterocyclic group, still more preferably is a bridging group or an aryl group, and these groups may have a substituent.
Examples and preferred ranges of substituents that the group represented by X' may have are the same as examples and preferable ranges of substituents that the group represented by Ar ^Y1 may have, which will be described later.

Examples of structural units having a cross-linking group include structural units represented by the following formulas. In the formula, Z ¹ represents an oxygen atom or a sulfur atom. ^XA represents a cross-linking group selected from cross-linking group A; When multiple X ^A are present, they may be the same or different. The preferred range of X ^A is the same as the preferred range of the cross-linking group in the compound having a cross-linking group.

(Other structural units)
The polymer compound having a cross-linking group is selected from the group consisting of structural units represented by the formula (X) and structural units represented by the formula (Y), since the light-emitting device of the present embodiment has an excellent external quantum efficiency. preferably contains at least one structural unit represented by the formula (X) and at least one structural unit selected from the group consisting of structural units represented by the formula (Y), and a bridging group It is preferable to include a structural unit having
A polymer compound having a cross-linking group comprises at least one structural unit selected from the group consisting of structural units represented by formula (X) and structural units represented by formula (Y), and a structural unit having a cross-linking group. and the structural unit having a cross-linking group is preferably different from the structural unit represented by the formula (X) and the structural unit represented by the formula (Y).
A polymer compound having a cross-linking group preferably contains a structural unit represented by the formula (Y) because the light-emitting device of the present embodiment has a more excellent external quantum efficiency, and the structural unit represented by the formula (Y) and a structural unit having a cross-linking group.
The polymer compound having a cross-linking group has an excellent hole-transporting property of the polymer compound having a cross-linking group, and the external quantum efficiency of the light-emitting device of the present embodiment is superior, so the structure represented by the formula (X) It preferably contains a unit, and more preferably contains a structural unit represented by formula (X) and a structural unit having a cross-linking group.
The polymer compound having a cross-linking group has an excellent hole-transport property of the polymer compound having a cross-linking group, and the external quantum efficiency of the light-emitting device of the present embodiment is further excellent. Therefore, the structure represented by the formula (X) It preferably contains a unit and a structural unit represented by formula (Y), and may contain a structural unit represented by formula (X), a structural unit represented by formula (Y), and a structural unit having a bridging group. more preferred.

When the polymer compound having a cross-linking group contains the structural unit represented by the formula (X), the content of the structural unit represented by the formula (X) is such that the polymer compound having the cross-linking group functions. It is acceptable if it is within the range of When the polymer compound having a cross-linking group contains the structural unit represented by formula (X), the content of the structural unit represented by formula (X) is the amount of the structural unit contained in the polymer compound having a cross-linking group. For example, it is 0.1 to 99.9 mol% with respect to the total content, the hole transport property of the polymer compound having a cross-linking group is excellent, and the external quantum efficiency of the light emitting device of the present embodiment is Since it is more excellent, it is preferably 1 to 99 mol%, more preferably 10 to 90 mol%, still more preferably 20 to 80 mol%, and particularly preferably 30 to 70 mol%.
The structural unit represented by formula (X) may be contained in one type or two or more types in the polymer compound having a cross-linking group.

When the polymer compound having a cross-linking group contains the structural unit represented by formula (Y), the content of the structural unit represented by formula (Y) is such that the polymer compound having a cross-linking group functions. It is acceptable as long as it is within the range of When the polymer compound having a cross-linking group contains the structural unit represented by formula (Y), the content of the structural unit represented by formula (Y) is the amount of the structural unit contained in the polymer compound having a cross-linking group. It is, for example, 0.1 to 99.9 mol% with respect to the total content, and is preferably 1 to 99 mol%, more preferably 1 to 99 mol%, because the external quantum efficiency of the light-emitting device of the present embodiment is superior. It is 10 to 90 mol %, more preferably 20 to 80 mol %, particularly preferably 30 to 70 mol %.
The structural unit represented by the formula (Y) may be contained alone or in combination of two or more in the polymer compound having a cross-linking group.

When the polymer compound having a cross-linking group contains a structural unit represented by formula (X) and/or a structural unit represented by formula (Y), and a structural unit having a cross-linking group, in formula (X) The total content of the structural unit represented by the formula (Y), the structural unit having a crosslinkable group, and the structural unit having a crosslinkable group may be within a range in which the function as a polymer compound having a crosslinkable group can be exhibited. When the polymer compound having a cross-linking group contains a structural unit represented by formula (X) and/or a structural unit represented by formula (Y), and a structural unit having a cross-linking group, in formula (X) The total content of the structural unit represented by the formula (Y) and the structural unit having a cross-linking group is based on the total content of the structural units contained in the polymer compound having a cross-linking group. , For example, 1 to 100 mol%, preferably 10 to 100 mol% because the polymer compound having a cross-linking group has excellent hole transport properties and the external quantum efficiency of the light emitting device of the present embodiment is further excellent. , more preferably 30 to 100 mol %, still more preferably 50 to 100 mol %, particularly preferably 70 to 100 mol %, particularly preferably 90 to 100 mol %.

The arylene group represented by the structural unit Ar ^Y1 represented by the formula (Y) is preferably monocyclic or bicyclic to hexacyclic because the light-emitting device of the present embodiment has superior external quantum efficiency. A group obtained by removing two hydrogen atoms directly bonded to the atoms constituting the ring from the aromatic hydrocarbon, more preferably a monocyclic, bicyclic or tricyclic aromatic hydrocarbon, the ring and more preferably benzene, naphthalene, anthracene, phenanthrene, dihydrophenanthrene or fluorene with two hydrogen atoms directly bonded to the atoms constituting the ring. is a group excluding, particularly preferably benzene, phenanthrene, dihydrophenanthrene or fluorene, a group excluding two hydrogen atoms directly bonded to the atoms constituting the ring, these groups have a substituent may be
The divalent heterocyclic group represented by Ar ^Y1 is preferably a monocyclic or bicyclic to hexacyclic heterocyclic compound, A group excluding two hydrogen atoms directly bonded to a ring-constituting atom, more preferably a monocyclic, bicyclic or tricyclic heterocyclic compound directly bonded to a ring-constituting atom more preferably pyridine, diazabenzene, triazine, azanaphthalene, diazanaphthalene, carbazole, dibenzofuran, dibenzothiophene, phenoxazine, phenothiazine, 9,10-dihydroacridine or 5, A group obtained by removing two hydrogen atoms directly bonded to a ring-constituting atom (preferably a carbon atom or a nitrogen atom, more preferably a carbon atom) from 10-dihydrophenazine, particularly preferably pyridine, diazabenzene, triazine , carbazole, dibenzofuran, dibenzothiophene, phenoxazine or phenothiazine, excluding two hydrogen atoms directly bonded to ring-constituting atoms (preferably carbon atoms or nitrogen atoms, more preferably carbon atoms), especially Preferably, it is a group obtained by removing two hydrogen atoms directly bonded to a ring-constituting atom (preferably a carbon atom or a nitrogen atom, more preferably a carbon atom) from carbazole, dibenzofuran, dibenzothiophene, phenoxazine or phenothiazine. , these groups may have a substituent.
In the divalent group in which at least one arylene group and at least one divalent heterocyclic group represented by Ar ^Y1 are directly bonded, the preferred ranges of the arylene group and the divalent heterocyclic group are, respectively, It is the same as the preferred range of the arylene group and divalent heterocyclic group represented by Ar ^Y1 .

In Ar ^Y1 , the "divalent group in which at least one arylene group and at least one divalent heterocyclic group are directly bonded" includes, for example, groups represented by the following formulae, The group may have a substituent.

Ar ^Y1 is preferably an optionally substituted arylene group because the light-emitting device of this embodiment has a more excellent external quantum efficiency.

The substituent that the group represented by Ar ^Y1 may have is 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 or a fluorine atom, more preferably an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, a monovalent heterocyclic group or a substituted amino group, still more preferably an alkyl group or a cycloalkyl A group, an aryl group, a monovalent heterocyclic group or a substituted amino group, particularly preferably an alkyl group, a cycloalkyl group or an aryl group, and these groups may further have a substituent.
The aryl group in the substituent that the group represented by Ar ^Y1 may have is preferably monocyclic or bicyclic to hexacyclic because the light-emitting device of the present embodiment has superior external quantum efficiency. A group obtained by removing one hydrogen atom directly bonded to an atom constituting a ring from an aromatic hydrocarbon, more preferably a monocyclic, bicyclic or tricyclic aromatic hydrocarbon, A group in which one hydrogen atom directly bonded to a constituent atom is removed, more preferably benzene, naphthalene, anthracene, phenanthrene, dihydrophenanthrene or fluorene, and one hydrogen atom directly bonded to a ring-constituting atom is removed. groups, particularly preferably benzene, phenanthrene, dihydrophenanthrene or fluorene, from which one hydrogen atom directly bonded to a ring-constituting atom is removed, and these groups further have substituents. may be
The monovalent heterocyclic group in the substituent that the group represented by Ar ^Y1 may have is preferably monocyclic or bicyclic to A group obtained by removing one hydrogen atom directly bonded to an atom constituting a ring from a hexacyclic heterocyclic compound, more preferably a monocyclic, bicyclic or tricyclic heterocyclic compound is a group from which one hydrogen atom directly bonded to a ring-constituting atom is removed from, more preferably pyridine, diazabenzene, triazine, azanaphthalene, diazanaphthalene, carbazole, dibenzofuran, dibenzothiophene, phenoxazine, phenothiazine , 9,10-dihydroacridine or 5,10-dihydrophenazine, with one hydrogen atom directly bonded to a ring-constituting atom (preferably a carbon atom or a nitrogen atom) removed, particularly preferably pyridine , diazabenzene, triazine, carbazole, dibenzofuran, dibenzothiophene, phenoxazine or phenothiazine, from which one hydrogen atom directly bonded to a ring-constituting atom (preferably a carbon atom or a nitrogen atom) is removed, and these groups may further have a substituent.
In the substituted amino group in the substituent that may be possessed by the group represented by Ar ^Y1 , the substituent possessed by the amino group is preferably an aryl group or a monovalent heterocyclic group, more preferably an aryl group. The group may further have a substituent. Examples and preferred ranges of the aryl group and monovalent heterocyclic group in the substituent of the amino group are the aryl group and monovalent heterocyclic group in the substituent that the group represented by Ar ^Y1 may have, respectively. is the same as the example and preferred range of

The substituent that the group represented by Ar ^Y1 may further have preferably has an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, an aryloxy group, monovalent heterocyclic group, substituted amino group or fluorine atom, more preferably alkyl group, cycloalkyl group, aryl group, monovalent heterocyclic group or substituted amino group, still more preferably alkyl group, a cycloalkyl group or an aryl group, particularly preferably an alkyl group or a cycloalkyl group. These groups may further have a substituent, but preferably have no further substituent. .
Examples and preferred ranges ^of the aryl group, monovalent heterocyclic group and substituted amino group in the substituent that the group represented by Ar Y1 may further have are Ar ^Y1 are the same as the examples and preferred ranges of the aryl group, monovalent heterocyclic group and substituted amino group in the substituents that the group may have.

The structural unit represented by formula (Y) is preferably a structural unit represented by formula (Y-1) or formula (Y-2) because the light-emitting device of the present embodiment has superior external quantum efficiency. be.

［式中、
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、アリールオキシ基、１価の複素環基、置換アミノ基又はフッ素原子を表し、これらの基は置換基を有していてもよい。該置換基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く、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。複数存在するＲ^Ｙ１は、同一でも異なっていてもよく、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。
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、アリールオキシ基、１価の複素環基、置換アミノ基又はフッ素原子を表し、これらの基は置換基を有していてもよい。該置換基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く、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。複数存在するＲ^Ｙ２は、同一でも異なっていてもよく、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。］

[In the formula,
R ^Y1 represents a hydrogen atom, 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 fluorine atom, and these groups are substituents may have When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. A plurality of R ^Y1 may be the same or different, and may be bonded to each other to form a ring together with the carbon atoms to which they are bonded.
X ^Y1 represents a group represented by -C(R ^Y2 ) ₂ -, -C(R ^Y2 )=C(R ^Y2 )- or -C(R ^Y2 ) ₂ -C(R ^Y2 ) ₂ -. R ^Y2 represents a hydrogen atom, 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 fluorine atom, and these groups are substituents may have When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. A plurality of ^RY2 may be the same or different, and may be bonded to each other to form a ring together with the carbon atoms to which they are bonded. ]

R ^Y1 is preferably a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, a monovalent heterocyclic group or a substituted amino group, more preferably a hydrogen atom, an alkyl group, a cycloalkyl group or an aryl group. and more preferably a hydrogen atom or an alkyl group, and these groups may have a substituent.

In formula (Y-1), at least one of R ^{1 Y1} (preferably at least two of R ^{1 Y1} ) is preferably an alkyl group, a cyclo an alkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, an aryloxy group, a monovalent heterocyclic group, a substituted amino group or a fluorine atom, more preferably an alkyl group, a cycloalkyl group, an aryl group or a monovalent It is a heterocyclic group or a substituted amino group, more preferably an alkyl group, a cycloalkyl group or an aryl group, particularly preferably an alkyl group, and these groups may have a substituent.

R ^Y2 is preferably an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, a monovalent heterocyclic group, or a substituted amino group, since the light-emitting device of this embodiment has a superior external quantum efficiency. , more preferably an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, still more preferably an alkyl group, a cycloalkyl group or an aryl group, these groups having a substituent may be

Examples and preferred ranges of ^the aryl group, monovalent heterocyclic group and substituted amino group for R ^Y1 and R ^Y2 are, respectively, the aryl group and the monovalent It is the same as the examples and preferred ranges of the heterocyclic group and the substituted amino group.
Examples and preferred ranges of substituents that R ^Y1 and R ^Y2 may have are the same as examples and preferred ranges of substituents that the group represented by Ar ^Y1 may have.

X ^Y1 is preferably represented by -C(R ^Y2 ) ₂ - or -C(R ^Y2 ) ₂ -C(R ^Y2 ) ₂ -, since the light-emitting device of this embodiment has superior external quantum efficiency. group, more preferably a group represented by -C(R ^Y2 ) ₂ -.

Examples of structural units represented by formula (Y) include structural units represented by the following formula. In the formula, Z ¹ represents an oxygen atom or a sulfur atom. In the formula, Z ² represents a group represented by -CH= or a group represented by -N=. When multiple Z ¹ are present, they may be the same or different. When multiple Z ² are present, they may be the same or different.

Structural units a ^X1 and a ^X2 represented by formula (X) are usually integers of 0 to 10, and are preferably integers of 0 to 5 because the light-emitting device of the present embodiment has superior external quantum efficiency. , more preferably an integer of 0 to 3, still more preferably an integer of 0 to 2, and particularly preferably 0 or 1.

R ^X1 , R ^X2 and R ^X3 are preferably an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, and more preferably an aryl group or a monovalent heterocyclic group, more preferably an aryl group, and these groups may have a substituent.
Examples and preferred ranges of the aryl group and the monovalent heterocyclic group in R ^X1 , R ^X2 and R ^X3 are, respectively, the aryl group and the monovalent heterocyclic group in the substituent that the group represented by Ar ^Y1 may have. It is the same as the example and preferred range of the cyclic group.

Ar ^X1 , Ar ^X2 , Ar ^X3 and Ar ^X4 are preferably arylene groups which may have a substituent, since the light-emitting device of this embodiment has superior external quantum efficiency.
Examples and preferred ranges of the arylene group and divalent heterocyclic group for Ar ^X1 , Ar ^X2 , Ar ^X3 and Ar ^X4 are the same as the examples and preferred ranges of the arylene group and divalent heterocyclic group for Ar ^Y1 respectively. be.
Examples and preferred arylene groups and divalent heterocyclic groups in the divalent group in which at least one arylene group and at least one divalent heterocyclic group represented by Ar ^X2 and Ar ^X4 are directly bonded The ranges are the same as the examples and preferred ranges of the arylene group and the divalent heterocyclic group in Ar ^Y1 , respectively.
The divalent group in which at least one arylene group and at least one divalent heterocyclic group in Ar ^X2 and Ar ^X4 are directly bonded to each other includes at least one arylene group and at least one divalent heterocyclic group in Ar ^Y1 . Examples thereof include the same divalent groups to which a valent heterocyclic group is directly bonded.

Examples and preferred ranges of the substituents that the groups represented by Ar ^X1 to Ar ^X4 and R ^X1 to R ^X3 may have are the examples and preferred ranges of the substituents that the group represented by Ar ^Y1 may have. Same as range.

Examples of structural units represented by formula (X) include structural units represented by the following formulas. In the formula, ^Z1 represents an oxygen atom or a sulfur atom.

Examples of polymer compounds having a cross-linking group include polymer compounds P-1 to P-12 shown in Table 1. Here, "other" means a structural unit represented by formula (Z), a structural unit represented by formula (Z'), a structural unit represented by formula (X), and a structural unit represented by formula (Y). means a structural unit other than the structural unit

［表中、ｐ’、ｑ’、ｒ’、ｓ’及びｔ’は、各構成単位のモル比率（モル％）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 (mol%) of each structural unit. p′+q′+r′+s′+t′=100 and 70≦p′+q′+r′+s′≦100. ]

The polymer compound having a cross-linking group may be a block copolymer, a random copolymer, an alternating copolymer, a graft copolymer, or may be in other forms. It is preferably a copolymer obtained by copolymerizing raw material monomers.
The polystyrene equivalent number average molecular weight of the polymer compound having a cross-linking group is preferably 5×10 ³ to 1×10 ⁶ , more preferably 1×10 ⁴ to 5×10 ⁵ , still more preferably 2×. 10 ⁴ to 2×10 ⁵ . The polystyrene equivalent weight average molecular weight of the polymer compound having a cross-linking group is preferably 1×10 ⁴ to 2×10 ⁶ , more preferably 2×10 ⁴ to 1×10 ⁶ , and still more preferably 5×. 10 ⁴ to 5×10 ⁵ .

(Method for Producing Polymer Compound Having Crosslinking Group)
A polymer compound having a cross-linking group can be produced using a known polymerization method described in Chemical Review (Chem. Rev.), Vol. 109, pp. 897-1091 (2009), Suzuki reaction, A method of polymerizing by a coupling reaction using a transition metal catalyst such as Yamamoto reaction, Buchwald reaction, Stille reaction, Negishi reaction and Kumada reaction is exemplified.
In the above polymerization method, the method of charging the monomers includes a method of charging the entire amount of the monomers into the reaction system at once, a method of charging a part of the monomers and reacting them, and then charging the remaining monomers all at once. Examples thereof include a method of continuously or dividedly charging, a method of continuously or dividingly charging a monomer, and the like.
Examples of transition metal catalysts include palladium catalysts and nickel catalysts.
The post-treatment of the polymerization reaction is performed by a known method, for example, a method of removing water-soluble impurities by liquid separation, adding the reaction solution after the polymerization reaction to a lower alcohol such as methanol, filtering the deposited precipitate, and drying it. method, etc., is performed singly or in combination. When the purity of the polymer compound having a cross-linking group is low, it can be purified by ordinary methods such as recrystallization, reprecipitation, continuous extraction using a Soxhlet extractor, and column chromatography.

[Low-molecular compound having a cross-linking group]
A low-molecular-weight compound having a cross-linking group is preferably a low-molecular-weight compound represented by the formula (Z'') because the light-emitting device of the present embodiment has a more excellent external quantum efficiency.

The examples and preferred ranges for m ^B1 are the same as the examples and preferred ranges for mA.
Examples and preferred ranges of m ^B2 are the same as those of c.
Examples and preferred ranges of m ^B3 are the same as those of m.
Examples and preferred ranges for Ar ⁷ are the same as those for Ar ⁵ .
The examples and preferred ranges of L ^B1 are the same as the examples and preferred ranges of L ^A.
Examples and preferred ranges of R''' are the same as those of R'.
Examples and preferred ranges of X'' are the same as those of X'.

Examples of low-molecular-weight compounds having a cross-linking group include the compounds shown below.

[Second composition]
The second layer comprises the compound (A-2), a crosslinked compound having a crosslinkable group, a hole transport material, a hole injection material, an electron transport material, an electron injection material, a light emitting material, and an antioxidant. It may be a layer containing a composition containing at least one selected from the group (hereinafter also referred to as "second composition"). However, in the second composition, the hole-transporting material, hole-injecting material, electron-transporting material, electron-injecting material, and light-emitting material are different from the compound (A-2). In the second composition, the hole-transporting material, the hole-injecting material, the electron-transporting material, the electron-injecting material, and the light-emitting material are different from crosslinked compounds having a crosslinking group.
The second composition contains the compound (A-2), a crosslinked compound having a crosslinkable group, a hole transport material, a hole injection material, an electron transport material, an electron injection material, a light emitting material and an antioxidant, Each may be contained singly or in combination of two or more.
Examples and preferred ranges of the hole-transporting material, hole-injecting material, electron-transporting material, electron-injecting material, light-emitting material and antioxidant contained in the second composition are respectively contained in the first composition. Examples and preferred ranges of the hole-transporting material, hole-injecting material, electron-transporting material, electron-injecting material, and antioxidant.
In the second composition, the compound (A-2), a crosslinked compound having a crosslinkable group, a hole-transporting material, a hole-injecting material, an electron-transporting material, an electron-injecting material, a light-emitting material, and an antioxidant The content may be within a range in which the function as the second composition is exhibited. In the second composition, the compound (A-2), a crosslinked compound having a crosslinkable group, a hole-transporting material, a hole-injecting material, an electron-transporting material, an electron-injecting material, a light-emitting material, and an antioxidant The content may be, for example, 1 to 100% by mass, 10 to 100% by mass, or 30 to 100% by mass, more preferably based on the total amount of the second composition. may be 50 to 100% by mass, 70 to 100% by mass, or 90 to 100% by mass.
In the second composition, the contents of the hole-transporting material, the hole-injecting material, the electron-transporting material, the electron-injecting material, and the light-emitting material are respectively When the total content is 100 parts by mass, it is usually 1 to 10000 parts by mass. In the second composition, the content of the antioxidant is usually 0.00001 to 10 when the total content of the crosslinked product of the compound (A-2) and the compound having a crosslinkable group is 100 parts by mass. part by mass.

[Second ink]
The second layer can be formed using, for example, a composition containing the compound (A-2), a compound having a cross-linking group, and a solvent (hereinafter also referred to as "second ink"). can.
The second ink may contain one kind of the compound (A-2), the compound having a cross-linking group and the solvent, or two or more kinds thereof.
The second ink can be suitably used for the wet method described in the section on the first ink.
The preferred range of viscosity for the second ink is the same as the preferred range for the viscosity of the first ink.
The example and preferred range of the solvent contained in the second ink are the same as the example and preferred range of the solvent contained in the first ink.
In the second ink, the content of the solvent is usually 1000 to 10000000 parts by mass when the total content of the compound (A-2) and the compound having a cross-linking group is 100 parts by mass.

The second ink may further contain at least one selected from the group consisting of hole-transporting materials, hole-injecting materials, electron-transporting materials, electron-injecting materials, light-emitting materials, and antioxidants.
The second ink may contain one of each of the hole transport material, the hole injection material, the electron transport material, the electron injection material, the luminescent material, and the antioxidant, or may contain two or more of them. may have been
Examples and preferred ranges of the hole-transporting material, the electron-transporting material, the hole-injecting material, the electron-injecting material, the light-emitting material, and the antioxidant, which the second ink may further include, are described in the second composition, respectively. are the same as the examples and preferred ranges of the hole transport material, electron transport material, hole injection material, electron injection material, light emitting material and antioxidant contained in .
The contents of the hole-transporting material, electron-transporting material, hole-injecting material, electron-injecting material, and light-emitting material, which the second ink may further contain, each have a compound (A-2) and a cross-linking group When the total content of the compounds is 100 parts by mass, it is usually 1 to 10000 parts by mass. The content of the antioxidant that the second ink may further contain is usually from 0.00001 to 0.00001 when the total content of the compound (A-2) and the compound having a cross-linking group is 100 parts by mass. 10 parts by mass.

<Light emitting element>
The light-emitting device of this embodiment is a light-emitting device having an anode, a cathode, and first and second layers provided between the anode and the cathode.
The light-emitting device of this embodiment may further have layers other than the anode, cathode, first layer, and second layer.

The light-emitting device of this embodiment has excellent external quantum efficiency. Although the reason for such an effect is not necessarily clear, two layers (first layer and second layer) provided between the anode and the cathode include the compound represented by the formula (H-1): By containing (compound (A-1) and compound (A-2)), for example, the charge injection barrier at the interface between the two layers is reduced, and/or the charge injection property between the two layers is improved. It is considered that the external quantum efficiency of the light emitting device of this embodiment is improved.

From the viewpoint of reducing the charge injection barrier at the interface between the two layers, the first layer and the second layer are preferably adjacent to each other.

In the light-emitting device of this embodiment, the compound (A-1) and the compound (A-2) may be the same or different.

In the light-emitting device of this embodiment, the first layer is usually a light-emitting layer (hereinafter referred to as "first light-emitting layer").
In the light-emitting device of the present embodiment, the second layer is usually a hole injection layer, a hole transport layer, and a light-emitting layer (that is, a light-emitting layer separate from the first light-emitting layer, hereinafter referred to as "second or an electron-transporting layer, preferably a hole-injecting layer, a hole-transporting layer or a second emitting layer, more preferably a hole-injecting layer or a hole-transporting layer. A hole transport layer is particularly preferred.

In the light-emitting device of this embodiment, the second layer is preferably a layer provided between the anode and the first layer because the external quantum efficiency of the light-emitting device of this embodiment is superior. It is more preferably a hole injection layer, a hole transport layer or a second light-emitting layer provided between the first layers, and a hole injection layer or a positive layer provided between the anode and the first layer. More preferably, it is a hole-transporting layer, and particularly preferably a hole-transporting layer provided between the anode and the first layer.

In the light-emitting device of this embodiment, when the second layer is the second light-emitting layer provided between the anode and the first layer, the external quantum efficiency of the light-emitting device of this embodiment is superior. It is preferred to further have at least one layer of a hole injection layer and a hole transport layer between the layer and the second layer. Further, when the second layer is the second light-emitting layer provided between the anode and the first layer, the external quantum efficiency of the light-emitting device of this embodiment is superior, so that the cathode and the first layer It is preferred to further have at least one layer of an electron injection layer and an electron transport layer between.
In the light-emitting device of this embodiment, when the second layer is the second light-emitting layer provided between the cathode and the first layer, the external quantum efficiency of the light-emitting device of this embodiment is superior. It is preferred to further have at least one layer of a hole injection layer and a hole transport layer between the first layer and the first layer. Further, when the second layer is the second light-emitting layer provided between the cathode and the first layer, the external quantum efficiency of the light-emitting device of this embodiment is superior, so that the cathode and the second layer It is preferred to further have at least one layer of an electron injection layer and an electron transport layer between.
In the light-emitting device of this embodiment, when the second layer is a hole transport layer provided between the anode and the first layer, the external quantum efficiency of the light-emitting device of this embodiment is superior. It is preferable to further have a hole injection layer between the second layer. Further, when the second layer is a hole-transporting layer provided between the anode and the first layer, the external quantum efficiency of the light-emitting device of this embodiment is superior, so It is preferred to further have at least one layer of an electron injection layer and an electron transport layer in between.
In the light-emitting device of this embodiment, when the second layer is a hole injection layer provided between the anode and the first layer, the external quantum efficiency of the light-emitting device of this embodiment is superior. It is preferred to further have a hole transport layer between the layer of and the second layer. Further, when the second layer is a hole injection layer provided between the anode and the first layer, the external quantum efficiency of the light emitting device of this embodiment is superior, so It is preferred to further have at least one layer of an electron injection layer and an electron transport layer in between.
In the light-emitting device of this embodiment, when the second layer is an electron transport layer provided between the cathode and the first layer, the external quantum efficiency of the light-emitting device of this embodiment is superior. It is preferable to further have at least one layer of a hole injection layer and a hole transport layer between the one layer. Further, when the second layer is an electron transport layer provided between the cathode and the first layer, the external quantum efficiency of the light-emitting device of this embodiment is superior, so the electron transport layer between the cathode and the second layer In addition, it is preferable to further have an electron injection layer.

Specific layer structures of the light-emitting device of this embodiment include, for example, layer structures represented by (D1) to (D17) below. The light-emitting device of this embodiment usually has a substrate, but the anode may be stacked on the substrate, or the cathode may be stacked on the substrate.

(D1) anode/hole-transport layer (second layer)/first light-emitting layer (first layer)/cathode (D2) anode/hole-injection layer/hole-transport layer (second layer)/ First light emitting layer (first layer)/cathode (D3) anode/hole injection layer/hole transport layer (second layer)/first light emitting layer (first layer)/electron transport layer/ Cathode (D4) anode/hole injection layer/hole transport layer (second layer)/first emitting layer (first layer)/electron injection layer/cathode (D5) anode/hole injection layer/positive hole-transporting layer (second layer)/first light-emitting layer (first layer)/electron-transporting layer/electron-injecting layer/cathode (D6) anode/hole-injecting layer/hole-transporting layer (second layer) )/first emitting layer (first layer)/second emitting layer/electron transport layer/electron injection layer/cathode (D7) anode/hole injection layer/hole transport layer (second layer)/ Second light-emitting layer/first light-emitting layer (first layer)/electron transport layer/electron injection layer/cathode (D8) anode/second light-emitting layer (second layer)/first light-emitting layer ( first layer)/cathode (D9) anode/hole injection layer/second light-emitting layer (second layer)/first light-emitting layer (first layer)/electron transport layer/cathode (D10) anode /hole injection layer/second light emitting layer (second layer)/first light emitting layer (first layer)/electron injection layer/cathode (D11) anode/hole injection layer/second light emitting layer (Second layer)/first light emitting layer (first layer)/electron transport layer/electron injection layer/cathode (D12) anode/hole injection layer/hole transport layer/second light emitting layer (second 2 layer)/first light emitting layer (first layer)/electron transport layer/electron injection layer/cathode (D13) anode/hole injection layer/hole transport layer/first light emitting layer (first layer)/second light emitting layer (second layer)/electron transport layer/electron injection layer/cathode (D14) anode/hole injection layer/hole transport layer/first light emitting layer (first layer) /electron transport layer (second layer)/electron injection layer/cathode (D15) anode/hole injection layer (second layer)/first light emitting layer (first layer)/cathode (D16) anode/ Hole injection layer (second layer)/first emitting layer (first layer)/electron transport layer/electron injection layer/cathode (D17) anode/hole injection layer (second layer)/holes Transport layer/first light emitting layer (first layer)/electron transport layer/electron injection layer/cathode

In (D1) to (D17) above, "/" means that the layers before and after it are laminated adjacent to each other. For example, "hole transport layer (second layer)/first light emitting layer (first layer)" means the combination of the hole transport layer (second layer) and the first light emitting layer (first layer). ) means that they are stacked adjacent to each other.

In the light emitting device of this embodiment, the anode, the hole injection layer, the hole transport layer, the light emitting layer, the electron transport layer, the electron injection layer and the cathode may each be provided with two or more layers, if necessary. . When there are a plurality of anodes, hole-injection layers, hole-transport layers, light-emitting layers, electron-transport layers, electron-injection layers, and cathodes, the materials constituting them may be the same or different.

In the light-emitting device of this embodiment, the thicknesses of the anode, the hole-injection layer, the hole-transport layer, the first layer, the second layer, the light-emitting layer, the electron-transport layer, the electron-injection layer, and the cathode are usually 1 nm. ~1 μm, preferably 2 nm to 500 nm, more preferably 5 nm to 150 nm.

In the light-emitting device of this embodiment, the order, number, and thickness of the layers to be stacked may be adjusted in consideration of the external quantum efficiency of the light-emitting device.

[First light-emitting layer]
The first light-emitting layer is typically the first layer.

[Second light-emitting layer]
The second light-emitting layer is usually a second layer or a layer containing a light-emitting material, preferably a layer containing a light-emitting material. When the second light-emitting layer is a layer containing a light-emitting material, the light-emitting material contained in the second light-emitting layer includes, for example, the light-emitting material that the second composition may contain. be done. The light-emitting material contained in the second light-emitting layer may be contained singly or in combination of two or more.
When the light-emitting device of this embodiment has a second light-emitting layer, and the hole injection layer described later, the hole transport layer described later, and the electron transport layer described later are not the second layer, the second light emission Preferably the layer is the second layer.

[Hole transport layer]
The hole-transporting layer is the second layer or a layer containing a hole-transporting material, preferably the second layer. When the hole-transporting layer is a layer containing a hole-transporting material, the hole-transporting material includes, for example, the hole-transporting material that the second composition may contain. The hole-transporting material contained in the hole-transporting layer may be contained alone or in combination of two or more.
When the light-emitting device of this embodiment has a hole-transporting layer, and the hole-injecting layer described later, the second light-emitting layer described above, and the electron-transporting layer described later are not the second layer, the hole-transporting layer is preferably the second layer.

[Electron transport layer]
The electron-transporting layer is a second layer or a layer containing an electron-transporting material, preferably a layer containing an electron-transporting material. When the electron-transporting layer is a layer containing an electron-transporting material, the electron-transporting material contained in the electron-transporting layer includes, for example, the electron-transporting material that the second composition may contain. . 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 of this embodiment has an electron-transporting layer, and the hole-injecting layer described later, the second light-emitting layer described above, and the hole-transporting layer described above are not the second layer, the electron-transporting layer is It is preferably the second layer.

[Hole injection layer]
The hole-injecting layer is the second layer or layer containing a hole-injecting material, preferably a layer containing a hole-injecting material. When the hole-injection layer is a layer containing a hole-injection material, the hole-injection material contained in the hole-injection layer includes, for example, the holes that the second composition may contain. Infusion materials are included. The hole injection material contained in the hole injection layer may be contained singly or in combination of two or more.
When the light-emitting device of this embodiment has a hole injection layer and the second light-emitting layer, the hole-transport layer, and the electron-transport layer are not the second layer, the hole-injection layer is preferably the second layer.

[Electron injection layer]
An electron injection layer is a layer containing an electron injection material. The electron injection material contained in the electron injection layer includes, for example, the electron injection material that the second composition may contain. The electron injection material contained in the electron injection layer may be contained singly or in combination of two or more.

[Substrate/electrode]
The substrate in the light-emitting device is preferably a substrate that does not chemically change during the formation of the electrodes and the formation of the organic layer. The substrate may be, for example, a substrate made of materials such as glass, plastic, silicon, and the like. If an opaque substrate is used, the electrode furthest from the substrate is preferably transparent or translucent.
Examples of materials for the anode include conductive metal oxides and translucent metals, preferably indium oxide, zinc oxide, tin oxide; indium-tin-oxide (ITO), indium-zinc-oxide, etc. conductive compounds of; silver-palladium-copper composite (APC); NESA, gold, platinum, silver, copper.
Examples of cathode materials include metals such as lithium, sodium, potassium, rubidium, cesium, beryllium, magnesium, calcium, strontium, barium, aluminum, zinc, and indium; alloys of two or more of them; alloys of one or more species with one or more of silver, copper, manganese, titanium, cobalt, nickel, tungsten, tin; and graphite and graphite intercalation compounds. Examples of alloys include magnesium-silver alloys, magnesium-indium alloys, magnesium-aluminum alloys, indium-silver alloys, lithium-aluminum alloys, lithium-magnesium alloys, lithium-indium alloys, and calcium-aluminum alloys.
In the light-emitting device of this embodiment, at least one of the anode and the cathode is usually transparent or translucent, and the anode is preferably transparent or translucent.
Methods for forming the anode and cathode include, for example, a vacuum deposition method, a sputtering method, an ion plating method, a plating method and a laminating method.

[Method for manufacturing light-emitting element]
In the method for manufacturing the light-emitting device of the present embodiment, when using a low-molecular-weight compound as a method for forming the first layer, the second layer, and layers other than the first layer and the second layer, for example, A dry method such as a vacuum deposition method and a wet method described in the section of the first ink can be used, and when a polymer compound is used, for example, the wet method described in the section of the first ink can be used.
In the method for manufacturing a light-emitting element of the present embodiment, the first layer, the second layer, and the layers other than the first layer and the second layer are the various inks described above, the various materials described above, and the It may be formed by the wet method described in the first ink section using the ink containing the solvent described in the first ink section, or may be formed by a dry method such as a vacuum deposition method.

Methods for forming the first layer and the second layer include, for example, a dry method and a wet method, and the wet method is preferable because it facilitates the production of the light emitting device of this embodiment. In the method of forming the first layer and the second layer, the dry method includes, for example, a vacuum deposition method. In the method of forming the first layer and the second layer, examples of the wet method include the wet method described in the section on the first ink.
When the first layer is formed by a wet method, it is preferable to use the first ink because it facilitates the manufacture of the light emitting device of this embodiment. That is, the first layer is preferably formed by a wet method using the first ink.
When the second layer is formed by a wet method, it is preferable to use the second ink because it facilitates the manufacture of the light emitting device of this embodiment. That is, the second layer is preferably formed by a wet method using the second ink.

In the method for producing a light-emitting device of the present embodiment, the layer containing a crosslinked compound of a compound having a crosslinkable group (e.g., the second layer) is formed, for example, by heating or It can be formed by cross-linking a compound having a cross-linking group contained in the layer by light irradiation (preferably heating). When the compound having a cross-linking group is contained in a layer in a cross-linked state (a cross-linked product of a compound having a cross-linking group), the layer is substantially insoluble in a solvent. Therefore, the layer containing the crosslinked product of the compound having a crosslinkable group can be suitably used for lamination of layers in the production of the light emitting device of this embodiment.

From the above point of view, in the method for manufacturing the light-emitting device of the present embodiment, manufacturing of the light-emitting device of the present embodiment is facilitated. After that, it is preferable to include a step of cross-linking the compound having a cross-linking group contained in the layer to form a second layer containing a cross-linked compound of the compound having a cross-linking group.
A layer containing a compound having a cross-linking group can be formed, for example, by a wet method using a composition (ink) containing a compound having a cross-linking group and the solvent described in the section of the second ink. can.
In the step of forming the second layer, the method of cross-linking the compound having a cross-linking group is preferably a method of cross-linking by heating or light irradiation because it facilitates the production of the light-emitting device of the present embodiment. A more preferred method is to

The heating temperature for crosslinking is usually 25° C. to 300° C., preferably 50° C. to 260° C., more preferably 130° C. to 230° C., still more preferably 180° C. to
210°C.
The heating time is usually 0.1 to 1000 minutes, preferably 0.5 to 500 minutes, more preferably 1 to 120 minutes, still more preferably 10 to 60 minutes. .
Types of light used for light irradiation are, for example, ultraviolet light, near-ultraviolet light, and visible light.

As the step of forming the second layer, for example, after forming the layer by a wet method using the second ink, the compound having a cross-linking group contained in the layer is cross-linked to form the second layer. Forming method; using the compound having a cross-linking group and the compound (A-2), a layer is formed by a dry method or a wet method (preferably a wet method), and then the compound having a cross-linking group contained in the layer is formed. a method of forming a second layer by cross-linking; and forming a layer containing a compound having a cross-linking group by a dry method or a wet method (preferably a wet method) using a compound having a cross-linking group, After cross-linking the compound having a cross-linking group contained in the layer to form a layer containing a cross-linked body of the compound having a cross-linking group, the compound (A-2) is incorporated into the layer containing the cross-linked body. , a method of forming the second layer.

Methods for analyzing components contained in the first layer, the second layer, or layers other than the first layer and the second layer include, for example, chemical separation analysis methods such as extraction, infrared spectroscopy instrumental analysis methods such as (IR), nuclear magnetic resonance spectroscopy (NMR), mass spectrometry (MS), and analytical methods combining chemical separation analysis methods and instrumental analysis methods.
By performing solid-liquid extraction using an organic solvent such as toluene, xylene, chloroform, tetrahydrofuran, etc. on the first layer, the second layer, or a layer other than the first layer and the second layer, It is possible to separate into a component that is substantially insoluble in an organic solvent (insoluble component) and a component that dissolves in an organic solvent (soluble component). Insoluble components can be analyzed by infrared spectroscopy or nuclear magnetic resonance spectroscopy, and dissolved components can be analyzed by nuclear magnetic resonance spectroscopy or mass spectroscopy.

The light-emitting device of this embodiment can be manufactured, for example, by sequentially laminating each layer on a substrate. Specifically, an anode is provided on a substrate, layers such as a hole injection layer and a hole transport layer are provided thereon, a light emitting layer is provided thereon, and an electron transport layer, an electron injection layer and the like are provided thereon. A light-emitting device can be manufactured by providing a layer and further laminating a cathode thereon. As another manufacturing method, a cathode is provided on a substrate, layers such as an electron injection layer, an electron transport layer, a light emitting layer, a hole transport layer, and a hole injection layer are provided thereon, and an anode is further provided thereon. A light-emitting device can be manufactured by stacking. In still another manufacturing method, an anode or a cathode-side base material having layers laminated on the anode and a cathode or a cathode-side base material having layers laminated on the cathode may be opposed and bonded to each other. can.

In the manufacture of the light emitting device of this embodiment, the material used for forming the hole injection layer, the material used for forming the light emitting layer, the material used for forming the hole transport layer, the material used for forming the electron transport layer, and the electron When the material used for forming the injection layer dissolves in the solvent used for forming the layers adjacent to the hole injection layer, the light-emitting layer, the hole transport layer, the electron transport layer, and the electron injection layer, It is preferred to avoid dissolving the material. Methods for avoiding material dissolution include i) a method of using a material having a cross-linking group, and ii) a method of providing a difference in the solubility of adjacent layers in a solvent. As the method i) above, for example, after forming a layer (for example, a hole transport layer) using a material having a crosslinkable group, the layer can be insolubilized by crosslinking the crosslinkable group, A layer different from the layer (for example, a light-emitting layer) can be laminated on the layer. Further, as the method ii), for example, after forming a layer (e.g., a light-emitting layer), an ink containing a solvent with low solubility is used for the layer, so that the layer A different layer (eg, an electron-transport layer) can be deposited.

[Use]
The light-emitting device of the present embodiment is suitable as a light source for backlighting of a liquid crystal display device, a light source for lighting, an organic EL lighting, a display device such as a computer, a television, and a mobile terminal (for example, an organic EL display and an organic EL television). can be used for

EXAMPLES The present invention will be described in more detail below 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 polystyrene-equivalent weight-average molecular weight (Mw) of the polymer compound were determined by size exclusion chromatography (SEC) using tetrahydrofuran as a mobile phase. In addition, each measurement condition of SEC is as follows.
A polymer compound to be measured was dissolved in tetrahydrofuran at a concentration of about 0.05% by mass, and 10 μL of the solution was injected into SEC. Mobile phase was run at a flow rate of 2.0 mL/min. As a column, PLgel MIXED-B (manufactured by Polymer Laboratories) was used. A UV-VIS detector (manufactured by Shimadzu Corporation, trade name: SPD-10Avp) was used as a detector.

For calculation of the _ΔEST value of the compound, the ground state of the compound was structurally optimized by density functional theory at the B3LYP level. At that time, 6-31G* was used as a basis function. Then, using the obtained optimized structure, _ΔEST of the compound was calculated by time-dependent density functional theory at the B3LYP level. The calculation was performed using Gaussian09 as a quantum chemical calculation program.

The maximum peak wavelength of the emission spectrum of the compound at room temperature was measured at room temperature with a spectrophotometer (manufactured by JASCO Corporation, FP-6500). A xylene solution in which a compound was dissolved in xylene at a concentration of about 8×10 ⁻⁴ mass % was used as a sample. Ultraviolet (UV) light with a wavelength of 325 nm was used as excitation light.

<Synthesis Example MM> Synthesis of Compounds MM1 to MM4 and MM7 to MM18 Compound MM1 was synthesized according to the method described in WO2015/145871.
Compound MM2 was synthesized according to the method described in WO2013/146806.
Compound MM3 was synthesized according to the method described in WO2005/049546.
Compound MM4 was synthesized according to the method described in JP-A-2010-189630.
Compound MM7, compound MM8 and compound MM11 were synthesized according to the method described in International Publication No. 2002/045184.
Compound MM9 was synthesized according to the method described in WO2011/049241.
Compound MM10 and compound MM14 were synthesized according to the method described in JP-A-2011-174062.
Compound MM12 was synthesized according to the method described in JP-A-2008-106241.
Compound MM13 and compound MM16 were synthesized according to the method described in WO2016/031639.
Compound MM15 was synthesized according to the method described in JP-A-2010-215886.
Compound MM17 was synthesized according to the method described in JP-A-2014-001328.
Compound MM18 was synthesized according to the method described in JP-A-2010-215886.

<Synthesis Example P> Synthesis of Polymer Compounds P1 to P8 and CP1 Polymer compounds P1 to P8 and CP1 were synthesized by the synthesis method described in Table 2 using the compounds of the types and molar ratios described in Table 2. . Mn and Mw of the obtained polymer compound were as shown in Table 2.
An example of the synthesis of the polymer compound P1 is described below.
Polymer compound P1 was synthesized using compound MM1, compound MM2 and compound MM3 according to the method described in International Publication No. 2015/145871. Mn of the polymer compound P1 was 2.3×10 ⁴ and Mw=1.2×10 ⁵ .
According to the theoretical values obtained from the amounts of the raw materials, the polymer compound P1 has a structural unit derived from the compound MM1, a structural unit derived from the compound MM2, and a structural unit derived from the compound MM3, which is 45: It is a copolymer made up in a 5:50 molar ratio.

<Compound M1>
The compound M1 used was manufactured by Luminescence Technology.

<Compounds H1 to H3 and B1 to B5>
Compound H1 and compound B1 were manufactured by Luminescence Technology.
Compound H2 was synthesized according to the method described in WO2011/098030.
Compound H3 was synthesized according to the method described in JP-A-2015-110751.
Compounds B2 and B4 were synthesized according to the method described in WO2015/102118.
Compound B3 was synthesized according to the method described in Angewandte Chemie International Edition, 2018, Vol. 57, pp. 11316-11320.
Compound B5 was synthesized according to the method described in Angewandte Chemie International Edition, 2020, Vol. 59, pp. 17442-17446.

The _ΔEST of compound B1 was 0.494 eV. The maximum peak wavelength of the emission spectrum of compound B1 at room temperature was 452 nm. The half width of the maximum peak of the emission spectrum of compound B1 at room temperature was 22 nm.
The _ΔEST of compound B2 was 0.457 eV. The maximum peak wavelength of the emission spectrum of compound B2 at room temperature was 454 nm. The half width of the maximum peak of the emission spectrum of compound B2 at room temperature was 21 nm.
The _ΔEST of compound B3 was 0.428 eV. The maximum peak wavelength of the emission spectrum of compound B3 at room temperature was 465 nm. The maximum peak half width of the emission spectrum of compound B3 at room temperature was 21 nm.
The _ΔEST of compound B4 was 0.472 eV. The maximum peak wavelength of the emission spectrum of compound B4 at room temperature was 440 nm. The half width of the maximum peak of the emission spectrum of compound B4 at room temperature was 19 nm.
The _ΔEST of compound B5 was 0.319 eV. The maximum peak wavelength of the emission spectrum of compound B5 at room temperature was 514 nm. The half width of the maximum peak of the emission spectrum of compound B5 at room temperature was 38 nm.

<Example D1> Production and evaluation of light emitting device D1 (formation of anode and hole injection layer)
An anode was formed by attaching an ITO film with a thickness of 45 nm to a glass substrate by a sputtering method. A film of ND-3202 (manufactured by Nissan Chemical Industries, Ltd.), which is a hole injection material, was formed on the anode to a thickness of 35 nm by spin coating. A hole injection layer was formed by heating the substrate having the hole injection layer laminated thereon on a hot plate at 50° C. for 3 minutes in an air atmosphere and further heating at 230° C. for 15 minutes.

(Formation of second layer)
Polymer compound P1 and compound H1 (polymer compound P1/compound H1=90% by mass/10% by mass) were dissolved in xylene at a concentration of 0.7% by mass. Using the obtained xylene solution, a film having a thickness of 20 nm was formed on the hole injection layer by a spin coating method, and heated on a hot plate at 180° C. for 60 minutes in a nitrogen gas atmosphere. 2 layers (hole transport layers) were formed. By this heating, the polymer compound P1 was in a crosslinked state.

(Formation of first layer)
Compound H1 and compound B1 (compound H1/compound B1=90 mass %/10 mass %) were dissolved in toluene at a concentration of 2 mass %. Using the obtained toluene solution, a film having a thickness of 60 nm was formed on the second layer by spin coating, and the first layer ( light-emitting layer) was formed.

(Formation of cathode)
After reducing the pressure of the substrate on which the first layer was formed to 1.0 × 10 ^-4 Pa or less in a vapor deposition machine, about 4 nm of sodium fluoride was deposited on the light-emitting layer as a cathode, and then the sodium fluoride layer was deposited. About 80 nm of aluminum was evaporated on top. After vapor deposition, the substrate on which the cathode was formed was sealed with a glass substrate to produce a light-emitting device D1.

(Evaluation of Light Emitting Element)
EL light emission was observed by applying a voltage to the light emitting element D1. The external quantum efficiency [%] and CIE chromaticity coordinates of the light-emitting element D1 at 50 mA/cm ² were measured.

<Example D2 and Comparative Example CD1> Production and Evaluation of Light-Emitting Elements D2 and CD1 %/10% by mass)", except that the materials and composition ratios (% by mass) shown in Table 3 were used in the same manner as in Example D1 to fabricate light-emitting elements D2 and CD1. In (formation of the second layer) of Example D2 and Comparative Example CD1, the polymer compound P1 was in a crosslinked state by heating.
EL emission was observed by applying a voltage to the light emitting elements D2 and CD1. The external quantum efficiency [%] and CIE chromaticity coordinates of the light emitting devices D2 and CD1 at 50 mA/cm ² were measured.

Table 3 shows the results of Examples D1 to D2 and Comparative Example CD1. The relative values of the external quantum efficiencies of the light-emitting elements D1 and D2 are shown when the external quantum efficiency of the light-emitting element CD1 is set to 1.00.

<Example D3> Production and Evaluation of Light-Emitting Device D3 In place of “Compound H1 and Compound B1 (Compound H1/Compound B1 = 90% by mass/10% by mass)” in (Formation of first layer) of Example D1 A light-emitting element D3 was fabricated in the same manner as in Example D1, except that "Compound H2 and Compound B1 (Compound H2/Compound B1=90% by mass/10% by mass)" were used.
EL light emission was observed by applying a voltage to the light emitting element D3. The external quantum efficiency [%] and CIE chromaticity coordinates of the light-emitting element D3 at 0.25 mA/cm ² were measured.

<Example D4 and Comparative Example CD2> Production and Evaluation of Light-Emitting Elements D4 and CD2 % / 10% by mass)”, using the materials and composition ratios (% by mass) described in Table 4, and further using “compound H1 and compound B1 (compound H1 / compound B1 = 90% by mass / 10% by mass)”, except that “compound H2 and compound B1 (compound H2 / compound B1 = 90% by mass / 10% by mass)” were used. Light-emitting elements D4 and CD2 were fabricated in the same manner. In Example D4 and Comparative Example CD2 (formation of the second layer), the polymer compound P1 was in a crosslinked state by heating.
EL emission was observed by applying a voltage to the light emitting elements D4 and CD2. The external quantum efficiency [%] and CIE chromaticity coordinates of the light-emitting elements D4 and CD2 at 0.25 mA/cm ² were measured.

Table 4 shows the results of Examples D3 to D4 and Comparative Example CD2. The relative values of the external quantum efficiencies of the light-emitting elements D3 and D4 are shown when the external quantum efficiency of the light-emitting element CD2 is set to 1.00.

<Example D5 and Comparative Example CD3> Production and Evaluation of Light-Emitting Elements D5 and CD3 %/10% by mass)", except that the materials and composition ratios (% by mass) shown in Table 5 were used in the same manner as in Example D1 to fabricate light-emitting elements D5 and CD3. In Example D5 and Comparative Example CD3 (formation of the second layer), compound M1 became crosslinked by heating.
EL emission was observed by applying a voltage to the light emitting elements D5 and CD3. The external quantum efficiency [%] and CIE chromaticity coordinates of the light emitting devices D5 and CD3 at 15 mA/cm ² were measured.

<Example D6> Production and evaluation of light-emitting element D6 "Polymer compound P1 and compound H1 (polymer compound P1/compound H1 = 90% by mass/10% by mass)" in (Formation of second layer) of Example D1 "Instead of "compound M1 and compound H2 (compound M1 / compound H2 = 90% by mass / 10% by mass)", furthermore, "compound H1 and compound B1 (Compound H1 / Compound B1 = 90% by mass / 10% by mass)”, except for using “Compound H2 and Compound B1 (Compound H2 / Compound B1 = 90% by mass / 10% by mass)” A light-emitting device D6 was produced in the same manner as in Example D1. In Example D6 (formation of the second layer), compound M1 was in a crosslinked state by heating.
EL light emission was observed by applying a voltage to the light emitting element D6. The external quantum efficiency [%] and CIE chromaticity coordinates of the light-emitting element D6 at 15 mA/cm ² were measured.

Table 5 shows the results of Examples D5 to D6 and Comparative Example CD3. The relative values of the external quantum efficiencies of the light-emitting elements D5 and D6 are shown when the external quantum efficiency of the light-emitting element CD3 is set to 1.00.

<Examples D7 to D9> Production and evaluation of light-emitting elements D7 to D9 “Compound H1 and compound B1 (compound H1/compound B1 = 90% by mass/10% by mass) in Example D1 (formation of first layer) , except that the materials and composition ratios (% by mass) shown in Table 6 were used in the same manner as in Example D1, to produce light-emitting devices D7 to D9.
EL light emission was observed by applying a voltage to the light emitting elements D7 to D9. The external quantum efficiency [%] and CIE chromaticity coordinates of the light emitting devices D7 to D9 at 20 mA/cm ² were measured.

<Example D10> Production and Evaluation of Light-Emitting Device D10 A light-emitting device D10 was produced in the same manner as in Example D1.
EL emission was observed by applying a voltage to the light emitting element D10. The external quantum efficiency [%] and CIE chromaticity coordinates of the light-emitting element D10 at 20 mA/cm ² were measured.

<Comparative Example CD4> Production and evaluation of light-emitting element CD4 Light emission was performed in the same manner as in Example D1 except that (formation of the second layer) in Example D1 was changed to the following (formation of the second layer-CD4). A device CD4 was produced.

(Formation of the second layer - CD4)
Polymer compound CP1 and compound B1 (polymer compound CP1/compound B1=90% by mass/10% by mass) were dissolved in xylene at a concentration of 0.7% by mass. Using the obtained xylene solution, a film having a thickness of 20 nm was formed on the hole injection layer by a spin coating method, and heated on a hot plate at 180° C. for 60 minutes in a nitrogen gas atmosphere. 2 layers (hole transport layers) were formed.

EL light emission was observed by applying a voltage to the light emitting element CD4. The external quantum efficiency [%] and CIE chromaticity coordinates of the light-emitting element CD4 at 20 mA/cm ² were measured.

Table 6 shows the results of Examples D7 to D10 and Comparative Example CD4. The relative values of the external quantum efficiencies of the light-emitting elements D7 to D10 are shown when the external quantum efficiency of the light-emitting element CD4 is set to 1.00.

<Example D11> Production and Evaluation of Light-Emitting Element D11 Instead of “Compound H1 and Compound B1 (Compound H1/Compound B1=90% by mass/10% by mass)” in (Formation of first layer) of Example D1 A light-emitting element D11 was fabricated in the same manner as in Example D1, except that "Compound H1 and Compound B5 (Compound H1/Compound B5=90% by mass/10% by mass)" were used.
EL light emission was observed by applying a voltage to the light emitting element D11. The external quantum efficiency [%] and CIE chromaticity coordinates of the light-emitting element D11 at 0.05 mA/cm ² were measured.

<Comparative Example CD5> Production and Evaluation of Light-Emitting Device CD5 "Polymer compound P1 and compound H1 (polymer compound P1/compound H1 = 90% by mass/10% by mass)" in (formation of second layer) of Example D1 ” instead of “polymer compound P1 (polymer compound P1 = 100% by mass)”, and further, “compound H1 and compound B1 (compound H1/compound B1 = 90% by mass / 10% by mass)”, except for using “Compound H1 and Compound B5 (Compound H1 / Compound B5 = 90% by mass / 10% by mass)”, in the same manner as in Example D1. , a light-emitting device CD5 was fabricated. In Comparative Example CD5 (formation of the second layer), the polymer compound P1 was in a crosslinked state by heating.
EL light emission was observed by applying a voltage to the light emitting element CD5. The external quantum efficiency [%] and CIE chromaticity coordinates of the light emitting device CD5 at 0.05 mA/cm ² were measured.

Table 7 shows the results of Example D11 and Comparative Example CD5. The relative value of the external quantum efficiency of the light-emitting element D11 when the external quantum efficiency of the light-emitting element CD5 is 1.00 is shown.

<Example D12 and Comparative Example CD6> Production and Evaluation of Light-Emitting Elements D12 and CD6 %/10% by mass)”, the materials and composition ratios (% by mass) described in Table 8 were used, and further, “compound H1 and compound B1 (compound H1 / compound B1 = 90% by mass / 10% by mass)”, except that “compound H3 and compound B5 (compound H3 / compound B5 = 90% by mass / 10% by mass)” were used. Light-emitting elements D12 and CD6 were fabricated in the same manner. In Example D12 and Comparative Example CD6 (formation of the second layer), the polymer compound P1 was in a crosslinked state by heating.
EL emission was observed by applying a voltage to the light emitting elements D12 and CD6. The external quantum efficiency [%] and CIE chromaticity coordinates of the light emitting devices D12 and CD6 at 0.05 mA/cm ² were measured.

Table 8 shows the results of Example D12 and Comparative Example CD6. The relative value of the external quantum efficiency of the light-emitting element D12 is shown when the external quantum efficiency of the light-emitting element CD6 is set to 1.00.

<Example D13 and Comparative Example CD7> Production and Evaluation of Light-Emitting Elements D13 and CD7 %/10% by mass)”, except that the materials and composition ratios (% by mass) shown in Table 9 were used in the same manner as in Example D1 to fabricate light-emitting elements D13 and CD7. In Example D13 and Comparative Example CD7 (formation of the second layer), the polymer compound P2 was in a crosslinked state by heating.
EL emission was observed by applying a voltage to the light emitting elements D13 and CD7. The external quantum efficiency [%] and CIE chromaticity coordinates of the light-emitting elements D13 and CD7 at 10 mA/cm ² were measured.

Table 9 shows the results of Example D13 and Comparative Example CD7. The relative value of the external quantum efficiency of the light-emitting element D13 is shown when the external quantum efficiency of the light-emitting element CD7 is set to 1.00.

<Example D14 and Comparative Example CD8> Production and Evaluation of Light-Emitting Elements D14 and CD8 %/10% by mass)", except that the materials and composition ratios (% by mass) shown in Table 10 were used in the same manner as in Example D1, to produce light-emitting elements D14 and CD8. In Example D14 and Comparative Example CD8 (formation of the second layer), the polymer compound P3 was in a crosslinked state by heating.
EL emission was observed by applying a voltage to the light emitting elements D14 and CD8. The external quantum efficiency [%] and CIE chromaticity coordinates of the light emitting devices D14 and CD8 at 2 mA/cm ² were measured.

Table 10 shows the results of Example D14 and Comparative Example CD8. The relative value of the external quantum efficiency of the light-emitting element D14 is shown when the external quantum efficiency of the light-emitting element CD8 is set to 1.00.

<Examples D15 and D16> Production and evaluation of light-emitting devices D15 and D16 In Example D1 (formation of second layer), “polymer compound P1 and compound H1 (polymer compound P1/compound H1 = 90 mass%/ Light-emitting elements D15 and D16 were produced in the same manner as in Example D1, except that the materials and composition ratios (% by mass) shown in Table 11 were used instead of 10% by mass). In Examples D15 and D16 (formation of the second layer), the polymer compound P4 was in a crosslinked state by heating.
EL emission was observed by applying a voltage to the light emitting elements D15 and D16. The external quantum efficiency [%] and CIE chromaticity coordinates of the light emitting devices D15 and D16 at 1 mA/cm ² were measured.

The results of Examples D15 and D16 are shown in Table 11. The relative value of the external quantum efficiency of the light-emitting element D15 is shown when the external quantum efficiency of the light-emitting element D16 is set to 1.00.

<Examples D17 and D18> Production and evaluation of light-emitting devices D17 and D18 "Polymer compound P1 and compound H1 (polymer compound P1/compound H1 = 90 mass%/ Light-emitting elements D17 and D18 were produced in the same manner as in Example D1, except that the materials and composition ratios (% by mass) shown in Table 12 were used instead of 10% by mass). In Examples D17 and D18 (formation of the second layer), the polymer compound P5 was in a crosslinked state by heating.
EL emission was observed by applying a voltage to the light emitting elements D17 and D18. The external quantum efficiency [%] and CIE chromaticity coordinates of the light emitting devices D17 and D18 at 10 mA/cm ² were measured.

The results of Examples D17 and D18 are shown in Table 12. The relative value of the external quantum efficiency of the light-emitting element D17 is shown when the external quantum efficiency of the light-emitting element D18 is set to 1.00.

<Example D19 and Comparative Example CD9> Production and Evaluation of Light-Emitting Elements D19 and CD9 %/10% by mass)”, except that the materials and composition ratios (% by mass) shown in Table 13 were used in the same manner as in Example D1, to produce light-emitting elements D19 and CD9. In Example D19 and Comparative Example CD9 (formation of the second layer), the polymer compound P6 was in a crosslinked state by heating.
EL emission was observed by applying a voltage to the light emitting elements D19 and CD9. The external quantum efficiency [%] and CIE chromaticity coordinates of the light-emitting elements D19 and CD9 at 10 mA/cm ² were measured.

Table 13 shows the results of Example D19 and Comparative Example CD9. The relative value of the external quantum efficiency of the light-emitting element D19 is shown when the external quantum efficiency of the light-emitting element CD9 is set to 1.00.

<Example D20 and Comparative Example CD10> Production and Evaluation of Light-Emitting Elements D20 and CD10 %/10% by mass)", except that the materials and composition ratios (% by mass) shown in Table 14 were used in the same manner as in Example D1, to produce light-emitting elements D20 and CD10. In Example D20 and Comparative Example CD10 (formation of the second layer), the polymer compound P7 was in a crosslinked state by heating.
EL emission was observed by applying a voltage to the light emitting elements D20 and CD10. The external quantum efficiency [%] at 1 mA/cm ² and the CIE chromaticity coordinates of the light-emitting elements D20 and CD10 were measured.

The results of Example D20 and Comparative Example CD10 are shown in Table 14. The relative value of the external quantum efficiency of the light-emitting element D20 is shown when the external quantum efficiency of the light-emitting element CD10 is set to 1.00.

<Examples D21 and D22> Production and evaluation of light-emitting devices D21 and D22 "Polymer compound P1 and compound H1 (polymer compound P1/compound H1 = 90 mass%/ Light-emitting elements D21 and D22 were fabricated in the same manner as in Example D1, except that the materials and composition ratios (% by mass) shown in Table 15 were used instead of 10% by mass). In Examples D21 and D22 (formation of the second layer), the polymer compound P8 was in a crosslinked state by heating.
EL emission was observed by applying a voltage to the light emitting elements D21 and D22. The external quantum efficiency [%] and CIE chromaticity coordinates of the light emitting devices D21 and D22 at 20 mA/cm ² were measured.

Table 15 shows the results of Examples D21 and D22. The relative value of the external quantum efficiency of the light-emitting element D21 is shown when the external quantum efficiency of the light-emitting element D22 is set to 1.00.

Claims (12)

A light emitting device having an anode, a cathode, and a first layer and a second layer provided between the anode and the cathode,
The first layer is
at least one compound (B-1) selected from compounds (B) having a condensed heterocyclic skeleton (b) containing a boron atom and a nitrogen atom in the ring;
A layer containing at least one compound (A-1) selected from compounds represented by formula (H-1),
The second layer is
at least one compound (A-2) selected from compounds represented by formula (H-1);
A light-emitting device, which is a layer containing a crosslinked product of a compound having a crosslinkable group.

[In the formula,
Ar ^H1 and Ar ^H2 each independently represent an aryl group, a monovalent heterocyclic group or a substituted amino group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded.
n ^H1 represents an integer of 0 or more.
L ^H1 represents a divalent group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. When multiple L ^H1 are present, they may be the same or different, and they may be directly bonded to each other or bonded via a divalent group to form a ring.
Ar ^H1 and Ar ^H2 may be directly bonded or bonded via a divalent group to form a ring. L ^H1 and Ar ^H1 may be directly bonded or bonded via a divalent group to form a ring. L ^H1 and Ar ^H2 may be directly bonded or bonded via a divalent group to form a ring. ] 2. The light-emitting device according to claim 1, wherein said compound having a cross-linking group is a polymer compound containing a structural unit having said cross-linking group. 3. The light-emitting device according to claim 2, wherein the structural unit having the cross-linking group is a structural unit represented by formula (Z) or a structural unit represented by formula (Z').

[In the formula,
n represents an integer of 1 or more.
nA represents an integer of 0 or more. When multiple nAs are present, they may be the same or different.
Ar ^Z represents a hydrocarbon group, a heterocyclic group, or a group in which at least one hydrocarbon group and at least one heterocyclic group are directly bonded, and these groups may have a substituent good. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded.
L ^A represents an alkylene group, a cycloalkylene group, an arylene group, a divalent heterocyclic group, a group represented by -N(R')-, an oxygen atom or a sulfur atom, and these groups have a substituent. You may have When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. R' represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. When multiple L ^A are present, they may be the same or different.
X represents a cross-linking group. When there are multiple X's, they may be the same or different. ]

[In the formula,
mA, m and c each independently represent an integer of 0 or more. When multiple mA are present, they may be the same or different. When there are multiple m's, they may be the same or different.
Ar ⁵ represents a hydrocarbon group, a heterocyclic group, or a group in which at least one hydrocarbon group and at least one heterocyclic group are directly bonded, and these groups may have a substituent good. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. When multiple Ar ⁵ are present, they may be the same or different.
Ar ⁴ and Ar ⁶ each independently represent an arylene group or a divalent heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded.
K ^A represents an alkylene group, a cycloalkylene group, an arylene group, a divalent heterocyclic group, a group represented by -N(R'')-, an oxygen atom or a sulfur atom, and these groups are substituents. may have. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. R'' represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. When multiple K ^A are present, they may be the same or different.
X' represents a hydrogen atom, a bridging group, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. When multiple X' are present, they may be the same or different. However, at least one X' is a bridging group. ] 3. The luminescence according to claim 2, wherein the polymer compound further comprises at least one structural unit selected from the group consisting of structural units represented by formula (X) and structural units represented by formula (Y). element.

[In the formula,
a ^X1 and a ^X2 each independently represent an integer of 0 or more.
Ar ^{1 X1} and Ar 2 ^X3 each independently represent an arylene group or a divalent heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded.
Ar ^X2 and Ar ^X4 each independently represent an arylene group, a divalent heterocyclic group, or a divalent group in which at least one arylene group and at least one divalent heterocyclic group are directly bonded; and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. When multiple Ar ^X2 are present, they may be the same or different. When multiple Ar ^X4 are present, they may be the same or different.
R ^X1 , R ^X2 and R ^X3 each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. When multiple R ^X2 are present, they may be the same or different. When multiple R ^X3 are present, they may be the same or different. ]

[Wherein, Ar ^Y represents an arylene group, a divalent heterocyclic group, or a divalent group in which at least one arylene group and at least one divalent heterocyclic group are directly bonded, The group may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. ] 2. The light-emitting device according to claim 1, wherein said compound having a cross-linking group is a compound represented by formula (Z'').

[In the formula,
m ^B1 , m ^B2 and m ^B3 each independently represent an integer of 0 or more. A plurality of m ^B1 may be the same or different. When multiple ^mB3 are present, they may be the same or different.
Ar ⁷ represents a hydrocarbon group, a heterocyclic group, or a group in which at least one hydrocarbon group and at least one heterocyclic group are directly bonded, and these groups may have a substituent good. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. When multiple Ar ⁷ are present, they may be the same or different.
L ^B1 represents an alkylene group, a cycloalkylene group, an arylene group, a divalent heterocyclic group, a group represented by -N(R''')-, an oxygen atom or a sulfur atom, and these groups are substituents may have When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. R''' represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. When multiple L ^B1 are present, they may be the same or different.
X'' represents a bridging group, a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. Multiple X'' may be the same or different. However, at least one of the plurality of X'' is a cross-linking group. ] 2. The light-emitting device according to claim 1, wherein said cross-linking group is at least one cross-linking group selected from Group A of cross-linking groups.
(Crosslinking group A group)

[In the formula, R ^XL represents a methylene group, an oxygen atom or a sulfur atom, and n ^XL represents an integer of 0 to 5. When multiple R ^XL are present, they may be the same or different. When multiple ^nXL are present, they may be the same or different. *1 represents the binding position. These bridging groups may have substituents, and when there are multiple substituents, they may be the same or different, and are bonded to each other to form a ring together with the atoms to which they are bonded. may ] 2. The compound according to claim 1, wherein the compound (B) is a compound represented by formula (1-1), a compound represented by formula (1-2) or a compound represented by formula (1-3). light-emitting element.

[In the formula,
Ar ¹ , Ar ² and Ar ³ each independently represent an aromatic hydrocarbon group or a heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded.
Y ¹ represents a group represented by -N(Ry)-.
Y ² and Y ³ each independently represent a single bond, an oxygen atom, a sulfur atom, a selenium atom, a group represented by -N(Ry)-, a group represented by -B(Ry)-, an alkylene group, It represents a cycloalkylene group, an arylene group or a divalent heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded.
Ry represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. When two or more Ry are present, they may be the same or different.
Y ¹ and Ar ¹ may be directly bonded or bonded via a divalent group to form a ring. Y ¹ and Ar ² may be directly bonded or bonded via a divalent group to form a ring. Y ² and Ar ¹ may be directly bonded or bonded via a divalent group to form a ring. Y ² and Ar ³ may be directly bonded or bonded via a divalent group to form a ring. Y ³ and Ar ² may be directly bonded or bonded via a divalent group to form a ring. Y ³ and Ar ³ may be directly bonded or bonded via a divalent group to form a ring. ] 8. The light emitting device according to claim 7, wherein said Y ² and said Y ³ are an oxygen atom, a sulfur atom or a group represented by -N(Ry)-. 8. The light-emitting device according to claim 7, wherein said Y ² and said Y ³ are groups represented by -N(Ry)-. Claims 1 to 9, wherein the first layer further contains at least one selected from the group consisting of a hole-transporting material, a hole-injecting material, an electron-transporting material, an electron-injecting material, a luminescent material and an antioxidant. The light-emitting device according to any one of . The light emitting device according to any one of claims 1 to 9, wherein the first layer and the second layer are adjacent. 10. The light-emitting device according to claim 1, wherein said second layer is a layer provided between said anode and said first layer.