JP2023050142A - Light-emitting element - Google Patents

Abstract

To provide a light-emitting element with a low driving voltage.SOLUTION: A light-emitting element includes an anode, a cathode, a first layer provided between the anode and the cathode, and a second layer provided between the first layer and the cathode. The first layer is a layer containing at least one kind selected from a group consisting of a low-molecule compound (B) including a condensed heterocyclic skeleton (b) including in a cycle a boron atom and at least one kind selected from a group consisting of an oxygen atom, a sulfur atom, a selenium atom, a sp3 carbon atom, and a nitrogen atom, and a polymer compound (B) including a constituent unit with a group excluding one or more hydrogen atoms from the low-molecule compound (B). The second layer is a layer containing at least one kind selected from a group consisting of a low-molecule compound with a particular structure and a polymer compound including at least one kind of a constituent unit selected from a group consisting of a constituent unit with a group excluding one or more hydrogen atoms from the low-molecule compound and a constituent unit expressed by a particular structure.SELECTED DRAWING: None

Description

The present disclosure 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 light-emitting layer containing compound B1. Note that this light-emitting element is a light-emitting element that does not have a second layer, which will be described later.

WO2020/203209

However, the driving voltage of the above light-emitting device is not always sufficiently low.
Accordingly, an object of one embodiment of the present disclosure is to provide a light-emitting element with a low driving voltage.

The present disclosure provides the following [1] to [14].

[1] A light-emitting device having an anode, a cathode, a first layer provided between the anode and the cathode, and a second layer provided between the first layer and the cathode,
The first layer has a condensed heterocyclic skeleton (b) containing a boron atom and at least one selected from the group consisting of an oxygen atom, a sulfur atom, a selenium atom, an ^sp3 carbon atom and a nitrogen atom in the ring. Contains at least one selected from the group consisting of a low-molecular-weight compound (B) and a high-molecular-weight compound (B) containing a structural unit having a group obtained by removing one or more hydrogen atoms from the low-molecular-weight compound (B). is a layer,
The second layer comprises a low-molecular-weight compound represented by the formula (ET-1), a low-molecular-weight compound represented by the formula (ET-2), and a low-molecular-weight compound represented by the formula (ET-1) A structural unit having a group from which one or more hydrogen atoms have been removed, a structural unit having a group from which one or more hydrogen atoms have been removed from the low-molecular compound represented by the formula (ET-2), represented by the formula (X) A layer containing at least one selected from the group consisting of structural units and polymer compounds containing at least one structural unit selected from the group consisting of structural units represented by formula (Y). light-emitting element.

[In the formula,
nE1 represents an integer of 1 or more.
Ar ^E1 represents an aromatic hydrocarbon group or a heterocyclic group, and these groups may have a substituent.
R ^E1 represents a group represented by formula (ES-1). When multiple R ^E1 are present, they may be the same or different. ]
-R ^E3 - {(Q ^E1 ) _nE3 - Y ^E1 (M ^E1 ) _aE1 (Z ^E1 ) _bE1 } _mE1 (ES-1)
[In the formula,
nE3 and bE1 each independently represent an integer of 0 or greater, and aE1 and mE1 each independently represent an integer of 1 or greater. When multiple nE3, aE1 and bE1 are present, they may be the same or different. However, mE1 is 1 when R ^E3 is a single bond. aE1 and bE1 are selected such that the charge of the group represented by formula (ES-1) is zero.
R ^E3 represents a single bond, a hydrocarbon group, a heterocyclic group or O—R ^E3 ' (R ^E3 ' represents a hydrocarbon group or a heterocyclic group), and these groups have a substituent; may
Q ^E1 represents an alkylene group, a cycloalkylene group, an arylene group, an oxygen atom or a sulfur atom, and these groups may have a substituent. When multiple Q ^E1 are present, they may be the same or different.
Y ^E1 represents -CO ₂ ^- , -SO ₃ ^- , -SO ₂ ^- or -PO ₃ ^2- . When multiple Y ^E1 are present, they may be the same or different.
M ^E1 represents an alkali metal cation, an alkaline earth metal cation or an ammonium cation, and the ammonium cation may have a substituent. When multiple M ^E1 are present, they may be the same or different.
Z ^E1 is F ⁻ , Cl ⁻ , Br ⁻ , I ⁻ , OH ⁻ , B(R ^E4 ) ₄ ⁻ , R ^E4 SO ₃ ⁻ , R ^E4 COO ⁻ , NO ₃ ⁻ , SO ₄ ²⁻ , HSO ₄ ⁻ , PO ₄ ^3- , HPO ₄ ^2- , H ₂ PO ₄ ^- , BF ₄ ^- or PF ₆ ^- . R ^E4 represents an alkyl group, a cycloalkyl group or an aryl group, and these groups may have a substituent. When multiple Z ^E1 are present, they may be the same or different. ]

[In the formula,
nE2 represents an integer of 1 or more.
Ar ^E2 represents an aromatic hydrocarbon group or a heterocyclic group, and these groups may have a substituent.
R ^E2 represents a group represented by formula (ES-2). When multiple R ^E2 are present, they may be the same or different. ]
-R ^E5 - {(Q ^E2 ) _nE4 - Y ^E2 (M ^E2 ) _aE2 (Z ^E2 ) _bE2 } _mE2 (ES-2)
[In the formula,
nE4 and bE2 each independently represent an integer of 0 or greater, and aE2 and mE2 each independently represent an integer of 1 or greater. When multiple nE4, aE2 and bE2 are present, they may be the same or different. However, mE2 is 1 when R ^E5 is a single bond. aE2 and bE2 are selected such that the charge of the group represented by formula (ES-2) is zero.
R ^E5 represents a single bond, a hydrocarbon group, a heterocyclic group or O—R ^E5 ' (R ^E5 ' represents a hydrocarbon group or a heterocyclic group), and these groups have a substituent; may
Q ^E2 represents an alkylene group, a cycloalkylene group, an arylene group, an oxygen atom or a sulfur atom, and these groups may have a substituent. When multiple Q ^E2 are present, they may be the same or different.
Y ^E2 represents -C ⁺ R ^E6 ₂ , -N ⁺ R ^E6 ₃ , -P ⁺ R ^E6 ₃ , -S ⁺ R ^E6 ₂ or -I ⁺ R ^E6 ₂ . R ^E6 represents a hydrogen atom, an alkyl group, a cycloalkyl group or an aryl group, and these groups may have a substituent. A plurality of R ^E6 may be the same or different. When multiple Y ^E2 are present, they may be the same or different.
M ^E2 is F ⁻ , Cl ⁻ , Br ⁻ , I ⁻ , OH ⁻ , B(R ^E7 ) ₄ ⁻ , R ^E7 SO ₃ ⁻ , R ^E7 COO ⁻ , BF ₄ ⁻ , SbCl ₆ ⁻ or SbF ₆ ⁻ show. R ^E7 represents an alkyl group, a cycloalkyl group or an aryl group, and these groups may have a substituent.
When multiple M ^E2 are present, they may be the same or different.
Z ^E2 represents an alkali metal cation or an alkaline earth metal cation. When multiple Z ^E2 are present, they may be the same or different. ]

[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 second layer comprises a structural unit having a group obtained by removing one or more hydrogen atoms from the low-molecular-weight compound represented by the formula (ET-1) and the low-molecular-weight compound represented by the formula (ET-2) The light-emitting device according to [1], which is a layer containing a polymer compound containing at least one structural unit selected from the group consisting of structural units having a group obtained by removing one or more hydrogen atoms from .
[3] Described in [1] or [2], wherein the condensed heterocyclic skeleton (b) contains a boron atom and at least one selected from the group consisting of an oxygen atom, a sulfur atom and a nitrogen atom in the ring. light-emitting element.
[4] The light-emitting device according to [3], wherein the condensed heterocyclic skeleton (b) contains a boron atom and a nitrogen atom in the ring.
[5] The low-molecular-weight 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), [ 1] or the light-emitting device according to [2].

[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 an oxygen atom, a sulfur atom, a selenium atom, a group represented by -N(Ry)-, an alkylene group or a cycloalkylene 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 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. ]
[6] The light-emitting device according to [5], wherein Y ¹ , Y ² and Y ³ are an oxygen atom, a sulfur atom or a group represented by -N(Ry)-.
[7] The light-emitting device according to [5] or [6], wherein Y ¹ , Y ² and Y ³ are groups represented by -N(Ry)-.
[8] The first layer comprises a metal complex represented by formula (1) and a polymer compound ( The light-emitting device according to any one of [1] to [7], further comprising at least one selected from the group consisting of A).

[In the formula,
M represents a rhodium atom, a palladium atom, an iridium atom or a platinum atom.
ⁿ¹ represents an integer of 1 or more, and ⁿ² represents an integer of 0 or more. However, n ¹ +n ² is 3 when M is a rhodium atom or an iridium atom, and n ¹ +n ² is 2 when M is a palladium atom or a platinum atom.
E ¹ and E ² each independently represent a carbon atom or a nitrogen atom. When multiple E ¹ and E ² are present, they may be the same or different.
Ring L ¹ represents an aromatic heterocycle, and the ring 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 rings L ¹ are present, they may be the same or different.
Ring ^L2 represents an aromatic hydrocarbon ring or an aromatic heterocyclic ring, and these rings 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 there is more than one ring ^L2 , they may be the same or different.
The substituent that ring L ¹ may have and the substituent that ring L ² may have 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 be formed.
A ¹ -G ¹ -A ² represents an anionic bidentate ligand. A ¹ and A ² each independently represent a carbon atom, an oxygen atom or a nitrogen atom, and these atoms may be atoms constituting a ring. G ¹ represents a single bond or an atomic group forming a bidentate ligand together with A ¹ and A ² . When multiple A ¹ -G ¹ -A ² are present, they may be the same or different. ]
[9] Ring L ¹ is an aromatic heterocyclic ring containing a 5-membered ring or an aromatic heterocyclic ring containing a 6-membered ring, these rings may have a substituent, and ring L ² is , an aromatic hydrocarbon ring containing a 5- or 6-membered ring, or an aromatic heterocyclic ring containing a 5- or 6-membered ring, these rings optionally having a substituent [8 ].
[10] Ring L ¹ is a pyridine ring, diazabenzene ring, azanaphthalene ring, diazanaphthalene ring, diazole ring or triazole ring, these rings may have a substituent, and ring L ² is a benzene ring, a pyridine ring or a diazabenzene ring, and these rings may have a substituent, the light-emitting device according to [8] or [9].
[11] Ring L ¹ is a diazole ring or triazole ring, which optionally has a substituent, and Ring L ² is a benzene ring, which has a substituent The light-emitting device according to any one of [8] to [10], which may be
[12] The first layer is selected from the group consisting of a compound represented by formula (H-1), and a structural unit represented by formula (X) and a structural unit represented by formula (Y) The light-emitting device according to any one of [1] to [11], further containing at least one selected from the group consisting of polymer compounds containing at least one structural unit.

[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 the 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. 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. ]

[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. ]
[13] 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 light-emitting material and an antioxidant, [1] The light-emitting device according to any one of [12].
[14] The light emitting device according to any one of [1] to [13], wherein the first layer and the second layer are adjacent to each other.

According to an embodiment of the present disclosure, it is possible to provide a light emitting device with low driving voltage.

Preferred embodiments of the present disclosure 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 from the viewpoint of the light emitting properties of the light emitting device of the present disclosure. 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. group, octyl group, 2-ethylhexyl group, 3-propylheptyl group, decyl group, 3,7-dimethyloctyl group, 2-ethyloctyl group, 2-hexyldecyl group, dodecyl group, and hydrogen atoms in these groups Some or all of the groups substituted with substituents (e.g., trifluoromethyl group, pentafluoroethyl group, perfluorobutyl group, perfluorohexyl group, perfluorooctyl 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, methylene group, ethylene group, propylene group, butylene group, hexylene group, 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 group is a monocyclic aromatic hydrocarbon or polycyclic aromatic hydrocarbon group in which one or more hydrogen atoms directly bonded to the carbon atoms constituting the ring are removed, and a plurality of groups are bonded. may be 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 usually 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 preferred. 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. A heterocyclic group is a group in which a plurality of groups are bonded by removing one or more hydrogen atoms directly bonded to the atoms constituting the ring from a monocyclic heterocyclic compound or a polycyclic heterocyclic compound, good too. 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 are further substituted with substituents.
Examples of substituted amino groups include 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 4-30, preferably 4-10, not including the carbon atoms of the substituents.
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.

［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。］ 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)). .
(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 ]

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. The divalent group may be a group 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 optimized structure, _ΔEST of the compound is calculated by time-dependent density functional theory at the B3LYP level. 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.

A light-emitting device of the present disclosure includes an anode, a cathode, a first layer provided between the anode and the cathode, and a second layer provided between the first layer and the cathode. is.

<First layer>
In the light-emitting device of the present disclosure, the first layer comprises at least one compound (hereinafter also referred to as "compound (B)") selected from the group consisting of low-molecular-weight compounds (B) and high-molecular-weight compounds (B). ) is a layer containing That is, the first layer is a layer containing compound (B).
The first layer may contain only one type of compound (B), or may contain two or more types.

The content of the compound (B) in the first layer may be within a range where the function as the first layer is exhibited. The content of the compound (B) in the first layer may be, for example, 0.01 to 100% by mass based on the total amount of the first layer, and the driving voltage of the light-emitting device of the present disclosure becomes lower. Therefore, it is preferably 0.05 to 90% by mass, more preferably 0.1 to 70% by mass, still more preferably 0.2 to 50% by mass, and particularly preferably 0.5 to 30% by mass. and particularly preferably 1 to 10% by mass.

[Compound (B)]
The compound (B) is at least one selected from the group consisting of low-molecular-weight compounds (B) and high-molecular-weight compounds (B).

(Low molecular weight compound (B))
The low ^- molecular-weight compound (B) is a condensed heterocyclic skeleton (b ) is a low-molecular-weight compound.
In the low-molecular-weight compound (B), when the condensed heterocyclic skeleton (b) contains a nitrogen atom, at least one of the nitrogen atoms contained in the condensed heterocyclic skeleton (b) is a nitrogen that does not form a double bond. It is preferably an atom, and more preferably all of the nitrogen atoms contained in the condensed heterocyclic skeleton (b) are nitrogen atoms that do not form double bonds.
The low-molecular-weight compound (B) is preferably a low-molecular-weight compound containing no transition metal element (that is, a low-molecular-weight compound composed only of typical elements).

The number of carbon atoms in the condensed heterocyclic skeleton (b) is generally 1 to 60, preferably 5 to 40, more preferably 10 to 25, not including the number of carbon atoms of substituents.
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, still more preferably 1 to 3, not including the number of boron atoms in the substituents. is 1.
The total number of oxygen atoms, sulfur atoms, selenium atoms, sp ³ carbon atoms and nitrogen atoms in the condensed heterocyclic skeleton (b) is usually 1 to 20, preferably 1 to 20, not including the number of substituent atoms. 10, more preferably 1 to 5, still more preferably 1 to 3, and particularly preferably 2.

The condensed heterocyclic skeleton (b) contains a boron atom and at least one selected from the group consisting of an oxygen atom, a sulfur atom and a nitrogen atom in the ring, since the driving voltage of the light-emitting device of the present disclosure is lower. It is more preferable to contain a boron atom and a nitrogen atom in the ring, and it is even more preferable to contain a nitrogen atom that does not form a double bond with the boron atom in the ring.

The condensed heterocyclic skeleton (b) is preferably a 3- to 12-ring condensed heterocyclic skeleton, more preferably a 3- to 6-ring condensed heterocyclic skeleton, because the driving voltage of the light-emitting device of the present disclosure is lower. and more preferably a pentacyclic condensed heterocyclic skeleton.

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 polycyclic heterocyclic group containing a boron atom and at least one selected from the group consisting of an oxygen atom, a sulfur atom, a selenium atom, an ^sp3 carbon atom and a nitrogen atom in the ring. It may be a group obtained by removing one or more hydrogen atoms directly bonded to atoms constituting a ring from a cyclic compound, and the group may have a substituent.
In the heterocyclic group (b′), a polycyclic heterocyclic compound preferably consists of boron atoms, oxygen atoms, sulfur atoms and nitrogen atoms, because the driving voltage of the light-emitting device of the present disclosure is lower. A polycyclic heterocyclic compound containing in the ring at least one selected from the group, more preferably a polycyclic heterocyclic compound containing a boron atom and a nitrogen atom in the ring More preferably, it is a polycyclic heterocyclic compound containing a boron atom and a nitrogen atom not forming a double bond in the ring.
In the heterocyclic group (b′), the polycyclic heterocyclic compound is preferably a 3- to 12-cyclic heterocyclic compound, more preferably a heterocyclic compound, since the driving voltage of the light-emitting device of the present disclosure is lower. is a 3- to 6-ring heterocyclic compound, more 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 and particularly preferably a group obtained by removing one hydrogen atom directly bonded to a ring-constituting atom from pyridine, diazabenzene or triazine, and these groups 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, monovalent heterocyclic group and substituted amino group in the substituent which 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 cyclic 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 low-molecular-weight compound (B) is preferably a thermally activated delayed fluorescence (TADF) compound, since the driving voltage of the light-emitting device of the present disclosure is lower.
Here, the heat-activated delayed fluorescence compound is a compound having heat-activated delayed fluorescence.

_ΔEST of the low-molecular-weight 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. However, it is preferably 0.60 eV or less, more preferably 0.55 eV or less, and still more preferably 0.50 eV or less, because the driving voltage of the light-emitting element of the present disclosure becomes lower. _ΔEST of the low-molecular-weight 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. may be 0.30 eV or more, or 0.40 eV or more.

The molecular weight of the low-molecular-weight 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 .

The low-molecular-weight compound (B) is a compound represented by formula (1-1), formula (1-2), or formula (1-3) because the driving voltage of the light-emitting device of the present disclosure is lower. is preferred, a compound represented by formula (1-2) or formula (1-3) is more 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 atoms constituting a 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 the atoms constituting the ring from an aromatic hydrocarbon or a monocyclic, bicyclic or tricyclic heterocyclic compound, more preferably , 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 diazabenzene is a group obtained by removing one or more hydrogen atoms directly bonded to ring-constituting atoms from benzene, and particularly preferably a group obtained by removing one or more hydrogen atoms directly bonded to ring-constituting atoms from benzene. , 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 ¹ is preferably an oxygen atom, a sulfur atom, a group represented by -N(Ry)- or an alkylene group, more preferably an oxygen atom, since the driving voltage of the light-emitting device of the present disclosure is lower. , a sulfur atom or a group represented by -N(Ry)-, more preferably a group represented by -N(Ry)-, and these groups may have a substituent.

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)-, -B A group represented by (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 or an alkylene group represented by, 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 -N It is a group represented by (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 ¹ , 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.

Since the driving voltage of the light-emitting device of the present disclosure is lower, all of Y ¹ , Y ² and Y ³ are preferably an oxygen atom, a sulfur atom or a group represented by -N(Ry)-, and Y All of ¹ , Y ² and Y ³ are more preferably groups represented by -N(Ry)-.

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 may be directly bonded or bonded via a divalent group to form a ring. preferably not.
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 through a divalent group to form a ring, examples and preferred ranges of R ⁰ in the divalent group are the same as examples and preferred ranges of Ry .

Y ¹ and Ar ² may be directly bonded or bonded via a divalent group to form a ring. preferably not. 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 may be directly bonded or bonded via a divalent group to form a ring. preferably not. 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 may be directly bonded or bonded via a divalent group to form a ring. preferably not. 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 may be directly bonded or bonded via a divalent group to form a ring. preferably not. 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 may be directly bonded or bonded via a divalent group to form a ring. preferably not. 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 low-molecular-weight compound (B) include compounds represented by the following formula and compound B1 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 the low-molecular-weight 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 the low-molecular-weight 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. It is preferably 480 nm or less.
The half width of the maximum peak of the emission spectrum of the low-molecular-weight 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, or tetrahydrofuran to prepare 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.

(Polymer compound (B))
The polymer compound (B) is a polymer compound containing a structural unit (hereinafter also referred to as “structural unit (B)”) having a group obtained by removing one or more hydrogen atoms from the low molecular weight compound (B).
The structural unit (B) is preferably a structural unit having a group obtained by removing 1 or more and 5 or less hydrogen atoms from the low-molecular-weight compound (B), and more preferably, because the synthesis of the polymer compound (B) is easy. is a structural unit having a group in which 1 to 3 hydrogen atoms are removed from the low-molecular-weight compound (B), more preferably a group in which 1 or 2 hydrogen atoms are removed from the low-molecular-weight compound (B) is a structural unit having
The structural unit (B) is preferably represented by formula (BP-1) or formula (BP- 2) or a structural unit represented by formula (BP-3), more preferably a structural unit represented by formula (BP-1) or formula (BP-2).

[In the formula,
^MBP1 represents a group obtained by removing one hydrogen atom from the low-molecular-weight compound (B).
^MBP2 represents a group obtained by removing two hydrogen atoms from the low-molecular-weight compound (B).
^MBP3 represents a group obtained by removing three hydrogen atoms from the low-molecular-weight compound (B).
L ^BP1 each independently represents an alkylene group, a cycloalkylene group, an arylene group, 2
represents a valent heterocyclic group, a group represented by -N(R ^BP1 )-, an oxygen atom or a sulfur atom, 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. ^RBP1 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 ^LBP1 are present, they may be the same or different.
^nBP1 represents an integer of 0 or more and 10 or less.
Ar ^BP1 represents a 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. ]

L ^BP1 is preferably an alkylene group, a cycloalkylene group, an arylene group or a divalent heterocyclic group, more preferably an alkylene group or an arylene group, still more preferably an arylene group, these groups may have a substituent.
Examples and preferred ranges of the arylene group and divalent heterocyclic group in ^LBP1 are the same as those of the arylene group and divalent heterocyclic group in Ar ^Y1 described below.
The alkylene group in ^LBP1 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 R ^BP1 are the same as examples and preferred ranges of R ^X1 to R ^X3 described later.

^nBP1 is preferably an integer of 0 to 5, preferably an integer of 0 to 3, more preferably 0 or 1, still more preferably 0.

The hydrocarbon group for Ar ^BP1 includes an optionally substituted aromatic hydrocarbon group and an optionally substituted aliphatic hydrocarbon group. The hydrocarbon group in Ar ^BP1 includes groups in which multiple of these groups are bonded.
In Ar ^BP1 , the aliphatic hydrocarbon group includes a group obtained by removing one hydrogen atom nBP ^from an alkylene group or a cycloalkylene group, preferably a group obtained by removing one hydrogen atom ^nBP from an alkylene group, These groups may have a substituent. Examples and preferred range of this alkylene group include the examples and preferred range of the alkylene group in L ^H1 described later.
In Ar ^BP1 , the aromatic hydrocarbon group includes a group obtained by removing one hydrogen atom n ^BP 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 ^BP1 includes a group obtained by removing one hydrogen atom n ^BP 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 examples of substituents that L ^BP1 and Ar ^{2 BP1} may have are the same as examples and preferred ranges of substituents that the group represented by Ar ^Y1 may have, which will be described later.

Examples of the structural unit (B) include structural units represented by the following formula.

[In the formula,
^RTS is a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, a monovalent heterocyclic group or a substituted amino group, and these groups may further have a substituent. Multiple ^RTSs may be the same or different. ]

Examples and preferred ranges of the aryl ^group , monovalent heterocyclic group and substituted amino group in R ^TS are, respectively, the aryl group, monovalent heterocyclic It is the same as the examples and preferred ranges of the cyclic group and the substituted amino group.
Examples and preferred ranges of substituents that R ^TS may have include examples and preferred ranges of substituents that the group represented by Ar ^Y1 described later may further have. are the same.

The content of the structural unit (B) contained in the polymer compound (B) may be within a range where the function of the polymer compound (B) is exhibited. The content of the structural unit (B) contained in the polymer compound (B) is, for example, 0.01 to 100 mol% with respect to the total content of the structural units contained in the polymer compound (B). , preferably 0.05 to 90 mol%, more preferably 0.1 to 70 mol%, still more preferably 0.2 to 50 mol%, because the driving voltage of the light-emitting device of the present disclosure is lower. , particularly preferably 0.5 to 30 mol %, particularly preferably 1 to 10 mol %. Only one type of structural unit (B) may be contained in the polymer compound (B), or two or more types thereof may be contained.

Since the polymer compound (B) lowers the driving voltage of the light emitting device of the present disclosure, it is a group consisting of a structural unit represented by the formula (X) described later and a structural unit represented by the formula (Y) described later. It is preferable to further contain at least one structural unit selected from the above. That is, the polymer compound (B) includes at least one structural unit selected from the group consisting of structural units represented by the formula (X) described later and structural units represented by the formula (Y) described later; It is preferably a polymer compound containing the unit (B).
The polymer compound (B) comprises at least one structural unit selected from the group consisting of structural units represented by the formula (X) described later and structural units represented by the formula (Y) described later, and a structural unit ( B), the structural unit (B) is preferably different from the structural unit represented by the formula (X) described later and the structural unit represented by the formula (Y) described later.
The polymer compound (B) preferably further contains a structural unit represented by formula (Y) described later, since the driving voltage of the light-emitting device of the present disclosure is lower.
The polymer compound (B) has excellent hole-transporting property of the polymer compound (B) and lowers the driving voltage of the light-emitting device of the present disclosure. It is preferable to further include
The polymer compound (B) has an excellent hole-transport property of the polymer compound (B) and further lowers the driving voltage of the light-emitting device of the present disclosure. and preferably further comprises a structural unit represented by formula (Y) described later.

When the polymer compound (B) contains a structural unit represented by the below-described formula (X), the content of the structural unit represented by the below-described formula (X) is such that the polymer compound (B) functions as It can be any range as long as it can be played. When the polymer compound (B) contains a structural unit represented by the below-described formula (X), the content of the structural unit represented by the below-described formula (X) is the constitution contained in the polymer compound (B). For example, it is 0.01 to 99.9 mol% with respect to the total content of the units, the hole transport property of the polymer compound (B) is excellent, and the driving voltage of the light emitting device of the present disclosure is higher. Since the mol %, particularly preferably 1 to 10 mol %.
The structural unit represented by formula (X) may be contained in the polymer compound (B) singly or in combination of two or more.

When the polymer compound (B) contains the structural unit represented by the formula (Y), the content of the structural unit represented by the formula (Y) is within the range in which the polymer compound (B) functions. If it is When the polymer compound (B) contains the structural unit represented by the formula (Y), the content of the structural unit represented by the formula (Y) is the total of the structural units contained in the polymer compound (B). With respect to the content, it is, for example, 1 to 99.99 mol %, and since the driving voltage of the light-emitting device of the present disclosure is lower, it is preferably 10 to 99.95 mol %, more preferably 30 to 99 mol %. 0.9 mol %, more preferably 50 to 99.8 mol %, particularly preferably 70 to 99.5 mol %, particularly preferably 90 to 99 mol %.
The structural unit represented by formula (Y) may be contained in the polymer compound (B) singly or in combination of two or more.

When the polymer compound (B) contains the structural unit represented by the formula (X) and/or the structural unit represented by the formula (Y), and the structural unit (B), it is represented by the formula (X) The total content of the structural unit represented by the formula (Y) and the structural unit (B) may be within a range in which the function of the polymer compound (B) can be exhibited. When the polymer compound (B) contains the structural unit represented by the formula (X) and/or the structural unit represented by the formula (Y), and the structural unit (B), it is represented by the formula (X) The total content of the structural unit represented by the formula (Y) and the structural unit (B) is, for example, 1 It is preferably 10 to 100 mol %, more preferably 10 to 100 mol %, because the hole transport property of the polymer compound (B) is excellent and the driving voltage of the light emitting device of the present disclosure is lower. It is 30 to 100 mol %, more preferably 50 to 100 mol %, particularly preferably 70 to 100 mol %, particularly preferably 90 to 100 mol %.

Examples of the polymer compound (B) include polymer compounds BP-1 to BP-4. Here, "other" means a structural unit other than the structural unit (B), the structural unit represented by formula (X), and the structural unit represented by formula (Y).

[In the table, p ^b , q ^b , r ^b and s ^b represent the molar ratio (mol %) of each structural unit. p ^b +q ^b +r ^b +s ^b =100 and 70≦p ^b +q ^b +r ^b ≦100. ]

The polymer compound (B) may be any of a block copolymer, a random copolymer, an alternating copolymer, a graft copolymer, or other modes. It is preferably a copolymer obtained by copolymerizing monomers.

The example and preferred range of the polystyrene-equivalent number average molecular weight of the polymer compound (B) are the same as the example and preferred range of the polystyrene-equivalent number average molecular weight of the first polymer compound described below. The example and preferred range of the polystyrene-equivalent weight average molecular weight of the polymer compound (B) are the same as the example and preferred range of the polystyrene-equivalent weight average molecular weight of the first polymer compound described below.

(Method for producing polymer compound (B))
The polymer compound (B) can be produced by a method similar to the method for producing the first polymer compound described below.

<Layer (1-1)>
Since the driving voltage of the light-emitting element of the present disclosure is lower in the first layer, one or more hydrogen atoms are removed from the metal complex represented by Formula (1) and the metal complex represented by Formula (1). It is preferable to further contain at least one compound (hereinafter also referred to as "compound (A)") selected from the group consisting of polymer compounds (A) containing a structural unit having a group. That is, the first layer is preferably a layer containing compound (B) and compound (A) (hereinafter also referred to as "layer (1-1)").
The layer (1-1) may contain only one kind of each of the compound (B) and the compound (A), or may contain two or more kinds thereof.

The total content of the compound (B) and the compound (A) in the layer (1-1) may be within a range in which the layer (1-1) functions. The total content of compound (B) and compound (A) in layer (1-1) may be, for example, 0.01 to 100% by mass based on the total amount of layer (1-1). Since the driving voltage of the disclosed light-emitting device becomes lower, it is preferably 0.1 to 99% by mass, more preferably 0.5 to 90% by mass, still more preferably 1 to 70% by mass, and particularly It is preferably 5 to 50% by weight, particularly preferably 10 to 30% by weight.
The content of the compound (B) in the layer (1-1) may be within a range in which the function of the layer (1-1) can be exhibited. The content of compound (B) in layer (1-1) is, for example, 0.01 to 99 parts by mass when the total content of compound (B) and compound (A) is 100 parts by mass. , Since the driving voltage of the light emitting device of the present disclosure is lower, it is preferably 0.05 to 90 parts by mass, more preferably 0.1 to 70 parts by mass, and still more preferably 0.5 to 50 parts by mass. , particularly preferably 1 to 30 parts by mass, particularly preferably 2 to 20 parts by mass.

In layer (1-1), compound (A) preferably physically, chemically or electrically interacts with compound (B). This interaction can, for example, enhance or tune the light emitting properties, charge transport properties or charge injection properties of the light emitting device of the present disclosure.
In the light-emitting device of the present disclosure, taking the light-emitting material as an example, the compound (A) and the compound (B) electrically interact to efficiently transfer electric energy from the compound (A) to the compound (B). By passing, the compound (B) can be made to emit light more efficiently, and the driving voltage of the light-emitting device of the present disclosure can be lowered.

From the above point of view, in the layer (1-1), the driving voltage of the light emitting device of the present disclosure is lower, so the compound (A) has a hole injection property, a hole transport property, an electron injection property, and an electron transport property. It is preferred to have at least one function selected.
From the above point of view, if a light-emitting material is used as an example in the layer (1-1), the driving voltage of the light-emitting element of the present disclosure will be lower, so the compound (B) preferably has light-emitting properties.
From the above point of view, in the layer (1-1), the lowest excited singlet state (S ₁ ) of the compound (A) has a lower driving voltage of the light-emitting device of the present disclosure, so the lowest singlet state of the compound (B) An energy level higher than the excited singlet state (S ₁ ) is preferred.
From the above point of view, in the layer (1-1), the lowest excited triplet state (T ₁ ) of the compound (A) has a lower driving voltage of the light-emitting device of the present disclosure, so the lowest An energy level higher than the excited triplet state (T ₁ ) is preferred.

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

[Compound (A)]
The compound (A) is at least one selected from the group consisting of the metal complex represented by Formula (1) and the polymer compound (A).

(Metal complex represented by formula (1))

The metal complex represented by formula (1) is preferably a low-molecular-weight compound.
The molecular weight of the metal complex represented by formula (1) is preferably 3×10 ² to 1×10 ⁴ , more preferably 4×10 ² to 7×10 ³ , still more preferably 5×10 2 to 7×10 3 . 10 ² to 5×10 ³ , particularly preferably 6×10 ² to 3×10 ³ , particularly preferably 7×10 ² to 2×10 ³ .

M is preferably an iridium atom or a platinum atom, more preferably an iridium atom, since the driving voltage of the light-emitting device of the present disclosure is lower.
When M is a rhodium atom or an iridium atom, ⁿ¹ is preferably 2 or 3, more preferably 3.
ⁿ¹ is preferably 2 when M is a palladium atom or a platinum atom.

At least one of E ¹ and E ² is preferably a carbon atom, more preferably E ¹ and E ² are carbon atoms.
E ¹ and E ² are preferably the same because the metal complex represented by formula (1) can be easily synthesized. In addition, since the metal complex represented by formula (1) can be easily synthesized, when there are a plurality of E ¹ 's, it is preferable that at least two of the plurality of E ^{1 's} are the same. are all the same. In ^addition , since the metal complex represented by formula (1) can be easily synthesized, when there are a plurality of E ² , it is preferable that at least two of the plurality of E ² are the same. are all the same.

The number of carbon atoms in the aromatic heterocyclic ring in ring L ¹ is preferably 1 to 30, more preferably 1 to 20, still more preferably 1 to 10, not including the number of carbon atoms in substituents. , particularly preferably 1 to 5, particularly preferably 1 to 3.
The number of heteroatoms in the aromatic heterocyclic ring in ring L ¹ is preferably 1 to 30, more preferably 1 to 10, still more preferably 1 to 5, not including the number of heteroatoms in the substituents. , particularly preferably 1 to 3.
Examples of the ring L ¹ include aromatic heterocycles containing one or more nitrogen atoms in the ring among the aromatic heterocycles exemplified in the section of the heterocyclic group described above, and the aromatic heterocycle may have a substituent. Among these, the ring L ¹ is preferably an aromatic heterocyclic ring containing a 5-membered ring or an aromatic heterocyclic ring containing a 6-membered ring, more preferably , an aromatic heterocycle containing a 5-membered ring containing 2 or more and 4 or less nitrogen atoms in the ring, or an aromatic heterocycle containing a 6-membered ring containing 1 or more and 4 or less nitrogen atoms in the ring and more preferably an aromatic heterocyclic ring containing a 5-membered ring containing 2 or 3 nitrogen atoms in the ring, or an aromatic containing a 6-membered ring containing 1 or 2 nitrogen atoms in the ring It is a heterocyclic ring, particularly preferably an aromatic heterocyclic ring containing a 5-membered ring containing 2 or 3 nitrogen atoms in the ring, and these rings may have a substituent. However, when ring L ¹ is a 6-membered aromatic heterocycle, E ¹ is preferably a carbon atom.
Ring L ¹ is preferably a monocyclic, bicyclic or tricyclic aromatic heterocyclic ring, more preferably a pyridine ring or a diazabenzene ring, since the driving voltage of the light-emitting device of the present disclosure is lower. , an azanaphthalene ring, a diazanaphthalene ring, a diazole ring or a triazole ring, more preferably a pyridine ring, an azanaphthalene ring, a diazole ring or a triazole ring, particularly preferably a diazole ring or a triazole ring, especially A triazole ring is preferred, and these rings may have a substituent.
Since the metal complex represented by formula (1) can be easily synthesized, when a plurality of ring L ¹ are present, it is preferable that at least two of the plurality of ring L ¹ are the same. ¹ are more preferably the same.

The number of carbon atoms in the aromatic hydrocarbon ring in ring L ² is preferably 6 to 60, more preferably 6 to 40, still more preferably 6 to 20, not including the number of carbon atoms in substituents. be.
Examples of the aromatic hydrocarbon ring in the ring L ² include the aromatic hydrocarbon rings exemplified in the section of the aromatic hydrocarbon group above, preferably an aromatic hydrocarbon ring containing a 5- or 6-membered ring. It is a hydrogen ring, and these aromatic hydrocarbon rings may have a substituent. Among these, the aromatic hydrocarbon ring in the ring L ² is preferably a monocyclic or bicyclic ring exemplified in the section of the aromatic hydrocarbon group above, because the driving voltage of the light-emitting element of the present disclosure is lower. a cyclic or tricyclic aromatic hydrocarbon ring (preferably an aromatic hydrocarbon ring containing a 5- or 6-membered ring), more preferably a benzene ring, a naphthalene ring, a fluorene ring, a phenanthrene ring or a dihydrophenanthrene It is a ring, more preferably a benzene ring or a fluorene ring, particularly preferably a benzene ring, and these rings may have a substituent.
The number of carbon atoms in the aromatic heterocyclic ring in ring L ² is preferably 1 to 60, more preferably 2 to 40, still more preferably 3 to 20, not including the number of carbon atoms in substituents. . The number of heteroatoms in the aromatic heterocyclic ring in ring L ² is preferably 1 to 10, more preferably 1 to 5, still more preferably 1 to 3, not including the number of heteroatoms in substituents. .
Examples of the aromatic heterocyclic ring in ring L ² include the aromatic heterocyclic rings exemplified in the section of the heterocyclic group described above, preferably an aromatic heterocyclic ring containing a 5- or 6-membered ring, These aromatic heterocycles may have a substituent. Among these, the aromatic heterocyclic ring in the ring L ² is preferably monocyclic, bicyclic or tricyclic, as exemplified in the section of the heterocyclic group above, since the driving voltage of the light-emitting device of the present disclosure is lower. cyclic aromatic heterocycle (preferably aromatic heterocycle containing 5- or 6-membered ring), more preferably pyridine ring, diazabenzene ring, azanaphthalene ring, diazanaphthalene ring, indole ring, benzofuran ring, benzothiophene ring, carbazole ring, azacarbazole ring, diazacarbazole ring, dibenzofuran ring or dibenzothiophene ring, more preferably pyridine ring, diazabenzene ring, carbazole ring, dibenzofuran ring or dibenzothiophene ring; A pyridine ring or a diazabenzene ring is particularly preferred, and these rings may have a substituent.
Ring L ² is preferably a monocyclic, bicyclic or tricyclic aromatic hydrocarbon ring (preferably a 5-membered ring or 6-membered ring (an aromatic hydrocarbon ring containing is a benzene ring, a fluorene ring, a pyridine ring, a diazabenzene ring, a carbazole ring, a dibenzofuran ring or a dibenzothiophene ring, more preferably a benzene ring, a pyridine ring or a diazabenzene ring, particularly preferably a benzene ring, These rings may have a substituent.
Since the metal complex represented by formula (1) can be easily synthesized, when there are a plurality of ring L ² , it is preferable that at least two of the plurality of ring L ² are the same. ² are more preferably the same.

Since the driving voltage of the light emitting device of the present disclosure is further lowered, the ring L ¹ is an aromatic heterocyclic ring containing a 5-membered ring (preferably a monocyclic, bicyclic or tricyclic aromatic heterocyclic ring) or an aromatic heterocycle containing a 6-membered ring (preferably a monocyclic, bicyclic or tricyclic aromatic heterocycle), and ring L ² is an aromatic containing a 5- or 6-membered ring aromatic hydrocarbon ring (preferably monocyclic, bicyclic or tricyclic aromatic hydrocarbon ring), or an aromatic heterocyclic ring containing a 5- or 6-membered ring (preferably monocyclic, bicyclic or tricyclic aromatic heterocycle), ring L ¹ is pyridine ring, diazabenzene ring, azanaphthalene ring, diazanaphthalene ring, diazole ring or triazole ring, and ring L ² is more preferably a benzene ring, fluorene ring, pyridine ring, diazabenzene ring, carbazole ring, dibenzofuran ring or dibenzothiophene ring, and ring L ¹ is a pyridine ring, diazabenzene ring, azanaphthalene ring, diazanaphthalene ring or diazole. ring or triazole ring, and ring L ² is more preferably a benzene ring, pyridine ring or diazabenzene ring, ring L ¹ is a pyridine ring, azanaphthalene ring, diazole ring or triazole ring, and ring L ² is particularly preferably a benzene ring, particularly preferably ring L ¹ is a diazole ring or triazole ring, ring L ² is a benzene ring, ring L ¹ is a triazole ring, and Ring ^L2 is particularly preferably a benzene ring, and these rings may have a substituent.

Preferred substituents that the ring L ¹ and ring L ² may have (hereinafter also referred to as "primary substituents") include an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group and 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, a monovalent heterocyclic group or a substituted amino group, still more preferably is an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, particularly preferably an alkyl group, a cycloalkyl group or an aryl group, and these groups are further substituted (hereinafter referred to as "secondary substituted Also referred to as "group").

At least one of ring L ¹ and ring L ² preferably has a primary substituent, as this results in a lower driving voltage for the light-emitting device of the present disclosure.
In the metal complex represented by formula (1), when at least one of ring L ¹ and ring L ² has a primary substituent and there are a plurality of ring L ¹ and ring L 2, a plurality of ring L 1 and ring L ² are present At least one ring out of ring L ¹ and ring L ² should have a primary substituent, but the driving voltage of ^the light-emitting device of the present disclosure is lower. At least two of ² preferably have a primary substituent, and more preferably at least three of the plurality of ring L ¹ and ring L ² have a primary substituent. Further, in the metal complex represented by formula (1), when at least one of ring L ¹ and ring L ² has a primary substituent, and a plurality of ring L ¹ and ring L ² are present, the present Since the driving voltage of the disclosed light-emitting device is lower, at least two of the plurality of rings L ¹ have primary substituents, or at least two of the plurality of rings L ² have primary substituents. More preferably, all of the plurality of ring L ¹ have a primary substituent, or all of the plurality of ring L ² have a primary substituent, and all of the plurality of ring L ¹ It is further preferred that has a primary substituent.
In the metal complex represented by formula (1), when at least one of ring L ¹ and ring L ² has a primary substituent, at least one of ring L ¹ and ring L ² has a primary substituent The number is usually 1 to 10, and preferably 1 to 5 because the metal complex represented by formula (1) can be easily synthesized and the driving voltage of the light emitting device of the present disclosure is lower. , more preferably 1 to 3, still more preferably 1 or 2.
In the metal complex represented by formula (1), when at least one of ring L ¹ and ring L ² has a primary substituent and M is a rhodium atom or an iridium atom, ring L ¹ and ring The total number of primary substituents that L ² has is usually 1 to 30, the metal complex represented by formula (1) can be easily synthesized, and the driving voltage of the light-emitting device of the present disclosure is Since it becomes lower, it is preferably 1 to 18, more preferably 2 to 12, and still more preferably 3 to 6.
In the metal complex represented by formula (1), when at least one of ring L ¹ and ring L ² has a primary substituent and M is a palladium atom or a platinum atom, ring L ¹ and ring The total number of primary substituents that L ² has is usually 1 to 20, the metal complex represented by formula (1) can be easily synthesized, and the driving voltage of the light-emitting device of the present disclosure is Since it becomes lower, it is preferably 1 to 12, more preferably 1 to 8, and still more preferably 2 to 4.

The aryl group in the primary substituent is preferably a monocyclic, bicyclic or tricyclic aromatic hydrocarbon group excluding one hydrogen atom directly bonded to a carbon atom constituting the ring, A phenyl group, a naphthyl group or a fluorenyl group is more preferred, and a phenyl group is even more preferred, and these groups may have a substituent.
As the monovalent heterocyclic group in the primary substituent, preferably, one hydrogen atom directly bonded to a carbon atom or heteroatom constituting a ring from a monocyclic, bicyclic or tricyclic heterocyclic compound and more preferably a pyridine ring, diazabenzene ring, triazine ring, azanaphthalene ring, diazanaphthalene ring, carbazole ring, dibenzofuran ring or dibenzothiophene ring directly to a carbon atom or heteroatom constituting the ring. A group in which one hydrogen atom is removed, more preferably a group in which one hydrogen atom directly bonded to a ring-constituting carbon atom is removed from a pyridine ring, a diazabenzene ring or a triazine ring, and these groups may have a substituent.
In the substituted amino group in the primary substituent, 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 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 same as those of the aryl group and monovalent heterocyclic group in the primary substituent.

Examples and preferred ranges of the secondary substituents (substituents that the primary substituent may further have) are the same as the examples and preferred ranges of the primary substituents.
The secondary substituent may further have a substituent (hereinafter also referred to as "tertiary substituent"). Examples and preferred ranges of tertiary substituents (substituents that secondary substituents may further have) are the same as examples and preferred ranges of primary substituents.
The tertiary substituent may further have a substituent (hereinafter also referred to as "quaternary substituent"). The quaternary substituent (substituent that the tertiary substituent may further have) is preferably an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, an aryloxy group, a monovalent a cyclic group, a substituted amino group or a fluorine atom, 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, which may further have a substituent, because the metal complex represented by the formula (1) can be easily synthesized. , and preferably have no substituents.
Examples and preferred ranges of the aryl group, monovalent heterocyclic group and substituted amino group in the secondary substituent, tertiary substituent and quaternary substituent are, respectively, the aryl group in the primary substituent, the monovalent heterocyclic group and It is the same as the example and preferred range of the substituted amino group.

(anionic bidentate ligand)
Examples of the anionic bidentate ligand represented by A ¹ -G ¹ -A ² include ligands represented by the following formulae. However, the anionic bidentate ligand represented by A ¹ -G ¹ -A ² is different from the ligand whose number is defined by the subscript n ¹ .

[In the formula, * represents a site that binds to M. ]

Examples of the metal complex represented by Formula (1) include the metal complexes shown below.

(Polymer compound (A))
The polymer compound (A) is a polymer containing a structural unit having a group obtained by removing one or more hydrogen atoms from the metal complex represented by formula (1) (hereinafter also referred to as "structural unit (A)"). is a compound.
Structural unit (A) is preferably a structural unit having a group obtained by removing 1 or more and 5 or less hydrogen atoms from the metal complex represented by formula (1), since synthesis of polymer compound (A) is easy. more preferably a structural unit having a group obtained by removing 1 or more and 3 or less hydrogen atoms from the metal complex represented by formula (1), and still more preferably a metal complex represented by formula (1) It is a structural unit having a group obtained by removing one or two hydrogen atoms from
The structural unit (A) is preferably represented by formula (AP-1) or formula (AP- 2) or a structural unit represented by formula (AP-3), more preferably a structural unit represented by formula (AP-1) or formula (AP-2), still more preferably a structural unit represented by formula ( It is a structural unit represented by AP-1).

[In the formula,
^MAP1 represents a group obtained by removing one hydrogen atom from the metal complex represented by formula (1).
^MAP2 represents a group obtained by removing two hydrogen atoms from the metal complex represented by formula (1).
^MAP3 represents a group obtained by removing three hydrogen atoms from the metal complex represented by formula (1).
L ^AP1 each independently represents an alkylene group, a cycloalkylene group, an arylene group, a divalent heterocyclic group, a group represented by -N(R ^AP1 )-, an oxygen atom or a sulfur atom, and these groups are It 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. ^RAP1 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 ^LAP1 are present, they may be the same or different.
n ^AP1 represents an integer of 0 or more and 10 or less.
Ar ^AP1 represents a 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. ]

The examples and preferred ranges of L ^AP1 are the same as the examples and preferred ranges of L ^BP1 .
The examples and preferred ranges of ^RAP1 are the same as the examples and preferred ranges of ^RBP1 .
The examples and preferred ranges of ^nAP1 are the same as the examples and preferred ranges of ^nBP1 .
The examples and preferred ranges of Ar ^AP1 are the same as the examples and preferred ranges of Ar ^BP1 .

Examples of structural units (A) include structural units represented by the following formulas.

[In the formula,
Z ² represents a group represented by -CH= or a group represented by -N=. When multiple Z ² are present, they may be the same or different.
^RA represents a hydrogen atom or a primary substituent. When multiple ^RAs are present, they may be the same or different. ]

The content of the structural unit (A) contained in the polymer compound (A) may be within a range in which the function of the polymer compound (A) is exhibited. The content of the structural unit (A) contained in the polymer compound (A) is, for example, 0.01 to 100 mol% with respect to the total content of the structural units contained in the polymer compound (A). is preferably 0.1 to 99 mol%, more preferably 0.5 to 90 mol%, still more preferably 1 to 70 mol%, because the driving voltage of the light-emitting device of the present disclosure is lower. , particularly preferably 5 to 50 mol %, particularly preferably 10 to 30 mol %. 1 type of structural units (A) may be contained in the polymer compound (A), and 2 or more types may be contained.

Since the polymer compound (A) lowers the driving voltage of the light emitting device of the present disclosure, it is a group consisting of a structural unit represented by the formula (X) described later and a structural unit represented by the formula (Y) described later. It is preferable to further contain at least one structural unit selected from the above. That is, the polymer compound (A) includes at least one structural unit selected from the group consisting of structural units represented by the formula (X) described later and structural units represented by the formula (Y) described later; It is preferably a polymer compound containing the unit (A).
The polymer compound (A) comprises at least one structural unit selected from the group consisting of structural units represented by the formula (X) described later and structural units represented by the formula (Y) described later, and a structural unit ( A), the structural unit (A) is preferably different from the structural unit represented by the formula (X) described later and the structural unit represented by the formula (Y) described later.
It is preferable that the polymer compound (A) further contains a structural unit represented by formula (Y), which will be described later, since the driving voltage of the light-emitting device of the present disclosure is lower.
The polymer compound (A) has an excellent hole-transport property, and the driving voltage of the light-emitting device of the present disclosure is lower. It is preferable to further include
The polymer compound (A) has an excellent hole-transport property, and the driving voltage of the light-emitting device of the present disclosure is lower. and preferably further contains a structural unit represented by formula (Y) described later.

When the polymer compound (A) contains a structural unit represented by the below-described formula (X), the content of the structural unit represented by the below-described formula (X) is such that the polymer compound (A) functions as It is acceptable as long as it is within the range where it can be played. When the polymer compound (A) contains a structural unit represented by the formula (X) described below, the content of the structural unit represented by the formula (X) described below is the constitution contained in the polymer compound (A). For example, it is 0.01 to 99.9 mol% with respect to the total content of the units, the hole transport property of the polymer compound (B) is excellent, and the driving voltage of the light emitting device of the present disclosure is higher. Since the mol %, particularly preferably 1 to 10 mol %.
The structural unit represented by formula (X) may be contained in the polymer compound (A) singly or in combination of two or more.

When the polymer compound (A) contains the structural unit represented by the formula (Y), the content of the structural unit represented by the formula (Y) is within the range in which the polymer compound (A) functions. If it is When the polymer compound (A) contains the structural unit represented by the formula (Y), the content of the structural unit represented by the formula (Y) is the total of the structural units contained in the polymer compound (A). With respect to the content, it is, for example, 0.1 to 99.99 mol %, and since the driving voltage of the light-emitting device of the present disclosure is lower, it is preferably 1 to 99.9 mol %, more preferably 10 99.5 mol %, more preferably 30 to 99 mol %, particularly preferably 50 to 95 mol %, particularly preferably 70 to 90 mol %.
The structural unit represented by formula (Y) may be contained in the polymer compound (A) singly or in combination of two or more.

When the polymer compound (A) contains the structural unit represented by the formula (X) and/or the structural unit represented by the formula (Y), and the structural unit (A), it is represented by the formula (X) The total content of the structural unit represented by the formula (Y), the structural unit represented by the formula (Y), and the structural unit (A) may be within a range in which the function of the polymer compound (A) can be exhibited. When the polymer compound (A) contains the structural unit represented by the formula (X) and/or the structural unit represented by the formula (Y), and the structural unit (A), it is represented by the formula (X) The total content of the structural unit represented by the formula (Y) and the structural unit (A) is, for example, 1 It is preferably 10 to 100 mol %, more preferably 10 to 100 mol %, because the hole transport property of the polymer compound (A) is excellent and the driving voltage of the light emitting device of the present disclosure is lower. It is 30 to 100 mol %, more preferably 50 to 100 mol %, particularly preferably 70 to 100 mol %, particularly preferably 90 to 100 mol %.

Examples of the polymer compound (A) include polymer compounds AP-1 to AP-4. Here, "other" means structural units (A), structural units represented by formula (X) and formula (Y)
means a structural unit other than the structural unit represented by

[In the table, p ^a , q ^a , r ^a and ^sa represent the molar ratio (mol %) of each structural unit. p ^a +q ^{a +} ra +s ^a =100 and 70≦ ^pa +q ^a + ^ra ≦100. ]

The polymer compound (A) may be any of 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 monomers.

The example and preferred range of the polystyrene-equivalent number average molecular weight of the polymer compound (A) are the same as the example and preferred range of the polystyrene-equivalent number average molecular weight of the first polymer compound described below. The example and preferred range of the polystyrene-equivalent weight average molecular weight of the polymer compound (A) are the same as the example and preferred range of the polystyrene-equivalent weight average molecular weight of the first polymer compound described below.

(Method for producing polymer compound (A))
The polymer compound (A) can be produced by a method similar to the method for producing the first polymer compound described below.

<Layer (1-2)>
Since the driving voltage of the light emitting device of the present disclosure is lower, the first layer includes the compound (B), the compound represented by formula (H-1), and the structural unit represented by formula (X). and at least one selected from the group consisting of polymer compounds containing at least one structural unit selected from the group consisting of structural units represented by formula (Y) (hereinafter also referred to as "first polymer compound") It is preferably a layer containing one type of compound (hereinafter also referred to as "first compound") and a layer (hereinafter also referred to as "layer (1-2)"). That is, the layer (1-2) is a layer containing the compound (B) and the first compound.
The layer (1-2) may contain only one kind of each of the compound (B) and the first compound, or may contain two or more kinds thereof.
The total content of the compound (B) and the first compound in the layer (1-2) may be within a range in which the layer (1-2) functions. The total content of the compound (B) and the first compound in the layer (1-2) may be, for example, 0.01 to 100% by mass based on the total amount of the layer (1-2). Since the driving voltage of the disclosed light-emitting device is lower, it is preferably 1 to 99.9% by mass, more preferably 10 to 99.9% by mass, still more preferably 30 to 99% by mass, and particularly It is preferably 50 to 95% by mass, particularly preferably 70 to 90% by mass.
The content of the compound (B) in the layer (1-2) may be within a range in which the function of the layer (1-2) can be exhibited. The content of the compound (B) in the layer (1-2) is, for example, 0.01 to 99 parts by mass when the total content of the compound (B) and the first compound is 100 parts by mass. , Since the driving voltage of the light emitting device of the present disclosure is lower, it is preferably 0.05 to 90 parts by mass, more preferably 0.1 to 70 parts by mass, and still more preferably 0.2 to 50 parts by mass. , particularly preferably 0.5 to 30 parts by mass, particularly preferably 1 to 10 parts by mass.

In layer (1-2), the first compound preferably physically, chemically or electrically interacts with compound (B). This interaction can, for example, enhance or tune the light emitting properties, charge transport properties or charge injection properties of the light emitting device of the present disclosure.
In the light-emitting element of the present disclosure, taking the light-emitting material as an example, the first compound and the compound (B) electrically interact to efficiently transfer electric energy from the first compound to the compound (B). By passing, the compound (B) can be made to emit light more efficiently, and the driving voltage of the light-emitting device of the present disclosure can be lowered.

From the above point of view, in the layer (1-2), the driving voltage of the light emitting device of the present disclosure is lower, so the first compound has a hole injection property, a hole transport property, an electron injection property, and an electron transport property. It is preferred to have at least one function selected.
From the above point of view, if the light-emitting material is used as an example in the layer (1-2), the driving voltage of the light-emitting element of the present disclosure will be lower, so the compound (B) preferably has light-emitting properties.
From the above point of view, in the layer (1-2), the lowest excited singlet state (S ₁ ) of the first compound has a lower driving voltage of the light emitting device of the present disclosure, so the lowest excited singlet state of the compound (B) An energy level higher than the excited singlet state (S ₁ ) is preferred.
From the above point of view, in the layer (1-2), the lowest excited triplet state (T ₁ ) of the first compound has a lower driving voltage of the light-emitting device of the present disclosure, so the lowest triplet state of the compound (B) An energy level higher than the excited triplet state (T ₁ ) is preferred.

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

[First compound]
The first compound is at least one selected from the group consisting of the compound represented by formula (H-1) and the first polymer 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 , since the driving voltage of the light-emitting device of the present disclosure is further lowered. 3×10 3 to 3×10 ³ , 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 ^H1 and Ar ^H2 are preferably directly bonded to ring-constituting atoms of monocyclic or 2- to 7-cyclic aromatic hydrocarbons, because the driving voltage of the light-emitting device of the present disclosure is lower. is 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 an atom constituting a ring is removed More preferably, it is a monocyclic, bicyclic or tricyclic aromatic hydrocarbon group in which one hydrogen atom directly bonded to a ring-constituting atom is removed, and these groups have substituents. You may have
Aryl groups in Ar ^H1 and Ar ^H2 are preferably benzene, naphthalene, anthracene, phenanthrene, dihydrophenanthrene, fluorene, benzanthracene, benzophenanthrene, benzofluorene, dibenzo a group obtained by removing one hydrogen atom directly bonded to a ring-constituting atom from anthracene, dibenzophenanthrene, dibenzofluorene, indenofluorene or benzofluoranthene, more preferably benzene, naphthalene, anthracene, phenanthrene, A group obtained by removing one hydrogen atom directly bonded to a ring-constituting atom from dihydrophenanthrene, fluorene, benzanthracene, benzophenanthrene or benzofluorene, 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. groups, and 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, , a boron atom and at least one selected from the group consisting of an oxygen atom, a sulfur atom, a selenium atom, an ^sp3 carbon atom and a nitrogen atom in the ring.
The monovalent heterocyclic groups in Ar ^H1 and Ar ^H2 are preferably monocyclic or di- to hepta-cyclic heterocyclic compounds (preferably condensed 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 containing no heterocyclic skeleton (b)), more preferably Atoms constituting a ring from a monocyclic or bi- to pentacyclic heterocyclic compound (preferably a monocyclic or bi- to pentacyclic heterocyclic compound containing no condensed heterocyclic skeleton (b)) is a group excluding one hydrogen atom directly bonded to the (monocyclic, bicyclic or tricyclic heterocyclic compound) by removing one hydrogen atom directly bonded to an atom constituting the ring, particularly preferably tricyclic heterocyclic compound (Preferably, a tricyclic heterocyclic compound that does not contain a condensed heterocyclic skeleton (b)) is a group in which one hydrogen atom directly bonded to an atom constituting the ring is removed, and these groups are substituted You may have a group.
The monovalent heterocyclic groups in Ar ^H1 and Ar ^H2 are preferably furan, thiophene, oxadiazole, thiadiazole, pyrrole, diazole, triazole, pyridine, diazabenzene, since the driving voltage of the light-emitting device of the present disclosure is lower. , triazine, azanaphthalene, diazanaphthalene, benzofuran, benzothiophene, indole, azaindole, diazaindole, benzodiazole, benzothiadiazole, benzotriazole, dibenzofuran, dibenzothiophene, carbazole, azacarbazole, diazacarbazole, 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, with one hydrogen atom directly bonded to a ring-constituting atom removed. and 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 di A group obtained by removing one hydrogen atom directly bonded to a ring-constituting atom from zaindenocarbazole, more preferably pyridine, diazabenzene, triazine, azanaphthalene, diazanaphthalene, dibenzofuran, dibenzothiophene, carbazole, aza carbazole, diazacarbazole, phenoxazine, phenothiazine, 9,10-dihydroacridine or 5,10-dihydrophenazine with one hydrogen atom directly bonded to a ring-constituting atom removed, particularly preferably pyridine , diazabenzene, triazine, azanaphthalene, diazanaphthalene, dibenzofuran, dibenzothiophene, or carbazole from which one hydrogen atom directly bonded to a ring-constituting atom is removed, particularly preferably dibenzofuran, dibenzothiophene, or carbazole. It is a group in which one hydrogen atom is directly bonded to a ring-constituting atom, 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 aryl group or a monovalent heterocyclic group, and these groups may have a substituent.
The aryl group and monovalent heterocyclic group in Ar ^H1 and Ar ^H2 are monocyclic, bicyclic or tricyclic aromatic hydrocarbons, or , a monocyclic, bicyclic or tricyclic heterocyclic compound (preferably a monocyclic, bicyclic or tricyclic heterocyclic compound that does not contain a condensed heterocyclic skeleton (b)) , is preferably a group in which one hydrogen atom directly bonded to an atom constituting the ring is removed, and the ring is selected from benzene, naphthalene, fluorene, pyridine, diazabenzene, triazine, azanaphthalene, diazanaphthalene, dibenzofuran, dibenzothiophene, or carbazole. A group in which one hydrogen atom directly bonded to a constituent atom is removed is more preferable, and a phenyl group, a naphthyl group, a fluorenyl group, a carbazolyl group, a dibenzothienyl group or a dibenzofuryl group is more preferable, 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 ), since the driving voltage of the light-emitting device of the present disclosure is lower. A group represented by -, a group represented by -(O=)P(R ⁰ )-, a group represented by -O-, a group represented by -S-, and -S(=O) ₂ - 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 preferably is an arylene group or a divalent heterocyclic group, 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 driving voltage of the light-emitting device of the present disclosure is lower, and more An arylene group or a divalent heterocyclic group is preferable, and these groups may have a substituent.

Among the divalent groups in L ^H1 , the arylene group is preferably a monocyclic or bi- to seven-cyclic aromatic hydrocarbon ring-constituting atom because the driving voltage of the light-emitting device of the present disclosure is lower. A group in which two hydrogen atoms directly bonded to are removed, more preferably a monocyclic or 2- to 5-cyclic aromatic hydrocarbon in which two hydrogen atoms directly bonded to the atoms constituting the ring are removed group, more preferably a group obtained by removing two hydrogen atoms directly bonded to atoms constituting the ring from a monocyclic, bicyclic or tricyclic aromatic hydrocarbon, and these groups are substituted You may have a group.
Among the divalent groups in L ^H1 , arylene groups are preferably benzene, naphthalene, anthracene, phenanthrene, dihydrophenanthrene, fluorene, benzoanthracene, benzophenanthrene, benzo a group obtained by removing two hydrogen atoms directly bonded to ring-constituting atoms from fluorene, dibenzoanthracene, dibenzophenanthrene, dibenzofluorene, indenofluorene or benzofluoranthene, more preferably benzene, naphthalene or anthracene , phenanthrene, dihydrophenanthrene, fluorene, benzanthracene, benzophenanthrene or benzofluorene, from which two hydrogen atoms directly bonded to atoms constituting the ring are removed, more preferably benzene, naphthalene, anthracene, phenanthrene, A group obtained by removing two hydrogen atoms directly bonded to ring-constituting atoms from dihydrophenanthrene or fluorene, 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. , a boron atom and at least one selected from the group consisting of an oxygen atom, a sulfur atom, a selenium atom, an ^sp3 carbon atom and a nitrogen atom in the ring.
Among the divalent groups in L ^H1 , a divalent heterocyclic group is preferably a monocyclic or di- to hepta-cyclic heterocyclic compound (preferably is a monocyclic or 2- to 7-ring heterocyclic compound that does not contain a condensed heterocyclic skeleton (b)), except for two hydrogen atoms directly bonded to the atoms (preferably carbon atoms) constituting the ring more preferably a monocyclic or bi- to pentacyclic heterocyclic compound (preferably a monocyclic or bi- to pentacyclic heterocyclic ring 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 the formula compound), more preferably a monocyclic, bicyclic or tricyclic heterocyclic compound A hydrogen atom directly bonded to an atom (preferably a carbon atom) constituting a ring from (preferably a monocyclic, bicyclic or tricyclic heterocyclic compound that does not contain a condensed heterocyclic skeleton (b)) A group excluding two, particularly preferably a tricyclic heterocyclic compound (preferably a tricyclic heterocyclic compound containing no condensed heterocyclic skeleton (b)) to form a ring. It is a group excluding two hydrogen atoms directly bonded to an atom (preferably a carbon atom), and these groups may have a substituent.
Among the divalent groups in L ^H1 , divalent heterocyclic groups 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 , phenoxazine, phenothiazine, 9,10-dihydroacridine, 5,10-dihydrophenazine, azaanthracene, diazaanthracene, azaphenanthrene, diazaphenanthrene, benzocarbazole, azabenzocarbazole, diazabenzocarbazole, benzonaphthofuran, directly bonded to a ring-constituting atom (preferably a carbon atom) of benzonaphthothiophene, dibenzocarbazole, indolocarbazole, indenocarbazole, azaindolocarbazole, diazaindolocarbazole, azaindenocarbazole or diazaindenocarbazole; 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, diazaine dolocarbazole, azaindenocarbazole or diazaindenocarbazole without two hydrogen atoms directly bonded to atoms (preferably carbon atoms) constituting the ring, more preferably pyridine, diazabenzene, triazine, Ring-constituting atoms (preferably carbon atoms) of azanaphthalene, diazanaphthalene, dibenzofuran, dibenzothiophene, carbazole, azacarbazole, diazacarbazole, phenoxazine, phenothiazine, 9,10-dihydroacridine or 5,10-dihydrophenazine ) is a group excluding two hydrogen atoms directly bonded to ), particularly preferably pyridine, diazabenzene, triazine, azanaphthalene, diazanaphthalene, dibenzofuran, dibenzothiophene or carbazole ring-constituting atoms (preferably carbon atoms ) in which 2 hydrogen atoms are directly bonded to ), and particularly preferably a group in which 2 hydrogen atoms directly bonded to a ring-constituting atom (preferably a carbon atom) from dibenzofuran, dibenzothiophene or carbazole are removed. and these groups 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 for 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 L ^H1 , examples and preferred ranges of substituents R ⁰ may have are the same as examples and preferred ranges of substituents 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.

(First polymer compound)
The first polymer compound is a polymer compound containing 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 first polymer compound is preferably a polymer compound different from the polymer compound (A) and the polymer compound (B), and is a polymer compound that does not contain the structural unit (A) and the structural unit (B). It is more preferable to have

The first polymer compound preferably contains a structural unit represented by formula (Y), since the driving voltage of the light-emitting device of the present disclosure is lower.
When the first polymer compound contains a structural unit represented by formula (Y), the content of the structural unit represented by formula (Y) contained in the first polymer compound is Any range is acceptable as long as it functions as a molecular compound. When the first polymer compound contains a structural unit represented by formula (Y), the content of the structural unit represented by formula (Y) contained in the first polymer compound is For example, it is 1 to 100 mol% with respect to the total content of structural units contained in the molecular compound, and is preferably 10 to 100 mol% because the driving voltage of the light-emitting device of the present disclosure is lower, It is 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 %.
In the first polymer compound, the structural unit represented by the formula (Y) may be contained alone or in combination of two or more.

The first polymer compound contains a structural unit represented by formula (X) because the first polymer compound has excellent hole-transport properties and the driving voltage of the light-emitting device of the present disclosure is lower. is preferred.
When the first polymer compound contains a structural unit represented by formula (X), the content of the structural unit represented by formula (X) contained in the first polymer compound is Any range is acceptable as long as the function as a molecular compound is exhibited. When the first polymer compound contains a structural unit represented by formula (X), the content of the structural unit represented by formula (X) contained in the first polymer compound is For example, it is 0.01 to 100 mol% with respect to the total content of the structural units contained in the molecular compound, the hole transport property of the first polymer compound is excellent, and the light emitting device of the present disclosure is obtained. Since the driving voltage becomes lower, it is preferably 0.05 to 90 mol%, more preferably 0.1 to 70 mol%, still more preferably 0.2 to 50 mol%, particularly preferably 0 .5 to 30 mol %, particularly preferably 1 to 10 mol %.
In the first polymer compound, the structural unit represented by the formula (X) may be contained in one kind, or may be contained in two or more kinds.

Since the first polymer compound has excellent hole-transport properties and the driving voltage of the light-emitting device of the present disclosure is lower, the structural unit represented by formula (Y) and the formula It preferably contains a structural unit represented by (X).
When the first polymer compound contains a structural unit represented by the formula (Y) and a structural unit represented by the formula (X), it is represented by the formula (Y) contained in the first polymer compound The total content of the structural units and the structural units represented by formula (X) may be within a range in which the function as the first polymer compound can be exhibited. When the first polymer compound contains a structural unit represented by the formula (Y) and a structural unit represented by the formula (X), it is represented by the formula (Y) contained in the first polymer compound The total content of the structural units and the structural units represented by the formula (X) is, for example, 1 to 100 mol%, the hole transport property of the first polymer compound is excellent, and the light emission of the present disclosure Since the drive voltage of the device becomes lower, it is preferably 10 to 100 mol%, more preferably 30 to 100 mol%, still more preferably 50 to 100 mol%, and particularly preferably 70 to 100 mol%. and 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 driving voltage of the light-emitting device of the present disclosure is lower. A group obtained by removing two hydrogen atoms directly bonded to atoms constituting a ring from an aromatic hydrocarbon, more preferably a monocyclic, bicyclic or tricyclic aromatic hydrocarbon, A group in which two hydrogen atoms directly bonded to the constituent atoms are removed, more preferably benzene, naphthalene, anthracene, phenanthrene, dihydrophenanthrene or fluorene, and two hydrogen atoms directly bonded to the ring-constituting atoms are removed. is a group from which benzene, phenanthrene, dihydrophenanthrene or fluorene is removed, and particularly preferably a group from which two hydrogen atoms directly bonded to atoms constituting the ring are removed from benzene, phenanthrene, dihydrophenanthrene or fluorene; may
The divalent heterocyclic group represented by Ar 2 ^Y1 is preferably selected from monocyclic or bicyclic to hexacyclic heterocyclic compounds, since the driving voltage of the light-emitting device of the present disclosure is lower. is a group excluding two hydrogen atoms that are directly bonded to the atoms that constitute a group with two hydrogen atoms removed, more preferably pyridine, diazabenzene, triazine, azanaphthalene, diazanaphthalene, carbazole, dibenzofuran, dibenzothiophene, phenoxazine, phenothiazine, 9,10-dihydroacridine or 5,10 - 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 dihydrophenazine, particularly preferably pyridine, diazabenzene, triazine, 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, and A group 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 ^{2 Y1} is preferably an optionally substituted arylene group because the driving voltage of the light-emitting device of the present disclosure is lower.

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 a monocyclic or bicyclic to hexacyclic aromatic group because the driving voltage of the light-emitting element of the present disclosure is lower. a group obtained by removing one hydrogen atom directly bonded to an atom constituting a ring from a group hydrocarbon, more preferably a monocyclic, bicyclic or tricyclic aromatic hydrocarbon more preferably benzene, naphthalene, anthracene, phenanthrene, dihydrophenanthrene or fluorene, excluding one hydrogen atom directly bonded to a ring-constituting atom. and particularly preferably a group obtained by removing one hydrogen atom directly bonded to a ring-constituting atom from benzene, phenanthrene, dihydrophenanthrene or fluorene, and these groups further have a substituent. may
The monovalent heterocyclic group in the substituent that the group represented by Ar ^Y1 may have is preferably monocyclic or bicyclic to 6 A group obtained by removing one hydrogen atom directly bonded to an atom constituting a ring from a cyclic heterocyclic compound, more preferably a monocyclic, bicyclic or tricyclic heterocyclic compound , a group in which one hydrogen atom directly bonded to a ring-constituting atom is removed, more preferably pyridine, diazabenzene, triazine, azanaphthalene, diazanaphthalene, carbazole, dibenzofuran, dibenzothiophene, phenoxazine, phenothiazine, 9,10-dihydroacridine or 5,10-dihydrophenazine, excluding one hydrogen atom directly bonded to an atom (preferably a carbon atom or a nitrogen atom) constituting a ring, particularly preferably pyridine, diazabenzene, triazine, carbazole, dibenzofuran, dibenzothiophene, phenoxazine or phenothiazine, with one hydrogen atom directly bonded to a ring-constituting atom (preferably a carbon atom or a nitrogen atom) removed, and these groups are Furthermore, it may 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 driving voltage of the light-emitting device of the present disclosure is lower. .

[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. 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,
cycloalkyl group, alkoxy group, cycloalkoxy group, aryl group, aryloxy group, monovalent heterocyclic group, substituted amino group or fluorine atom, more preferably alkyl group, cycloalkyl group, aryl group, monovalent 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 driving voltage of the light-emitting device of the present disclosure is lower. , more preferably an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, more preferably an alkyl group, a cycloalkyl group or an aryl group, and these groups have a substituent. may

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 a group represented by -C(R ^Y2 ) ₂ - or -C(R ^Y2 ) ₂ -C(R ^Y2 ) ₂ -, since the driving voltage of the light-emitting element of the present disclosure is lower. and more preferably a group represented by —C(R ^Y2 ) ₂ —.

Examples of the structural unit represented by the formula (Y) include a structural unit composed of an arylene group represented by the formula (Y-101)-the formula (Y-141), a structural unit represented by the formula (Y-201)-the formula (Y- 209), at least one arylene group and at least one divalent heterocyclic ring represented by formulas (Y-301)-(Y-306) A structural unit composed of a divalent group directly bonded to a group is exemplified.

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 driving voltage of the light-emitting device of the present disclosure is lower. , more preferably an integer of 0 to 3, 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, more preferably an aryl group, because the driving voltage of the light-emitting device of the present disclosure is lower. 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 optionally having substituents, since the driving voltage of the light-emitting device of the present disclosure becomes lower.
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.

Examples of the first polymer compound include polymer compounds HP-1 to HP-3.

[In the table, p, q and r indicate the molar ratio (mol %) of each structural unit. p+q+r=100 and 100≧p+q≧70. Other structural units mean structural units other than the structural units represented by the formula (Y) and the structural units represented by the formula (X). ]

The first polymer compound may be a block copolymer, a random copolymer, an alternating copolymer, or a graft copolymer. It is preferably a copolymer obtained by copolymerizing monomers.
The polystyrene equivalent number average molecular weight of the first polymer compound 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 first polymer compound is preferably 1×10 ⁴ to 2×10 ⁶ , more preferably 2×10 ⁴ to 1×10 ⁶ , still more preferably 5×10 ⁴ to 5×10 ⁵ .

(Method for producing first polymer compound)
The first polymer compound can be produced using a known polymerization method described in Chemical Review (Chem. Rev.), Vol. 109, pp. 897-1091 (2009), Suzuki reaction, Yamamoto reaction, Buchwald reaction, Stille reaction, Negishi reaction, and Kumada reaction.
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 first polymer compound is low, it can be purified by ordinary methods such as recrystallization, reprecipitation, continuous extraction using a Soxhlet extractor, column chromatography, and the like.

<Layer (1-3)>
Since the driving voltage of the light emitting device of the present disclosure is lower, the first layer is a layer containing the compound (A), the compound (B), and the first compound (hereinafter referred to as “layer (1-3 )”.) is preferred.
The layer (1-3) may contain only one kind of each of the compound (A), the compound (B) and the first compound, or may contain two or more kinds thereof.
The total content of the compound (A), the compound (B) and the first compound in the layer (1-3) may be within a range in which the layer (1-3) functions. The total content of the compound (A), the compound (B) and the first compound in the layer (1-3) is, for example, 1 to 100% by mass based on the total amount of the layer (1-3). Since the driving voltage of the light-emitting device of the present disclosure is often lower, it 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. is 70 to 100% by weight, particularly preferably 90 to 100% by weight.
The total content of the compound (A) and the compound (B) in the layer (1-3) may be within a range in which the layer (1-3) functions. The total content of the compound (A) and the compound (B) in the layer (1-3) is based on the total content of the compound (A), the compound (B) and the first compound being 100 parts by mass. , for example, 0.01 to 99.9 parts by mass, preferably 0.1 to 99 parts by mass, more preferably 0.5 to 90 parts by mass, because the driving voltage of the light-emitting device of the present disclosure is lower. parts, more preferably 1 to 70 parts by mass, particularly preferably 5 to 50 parts by mass, particularly preferably 10 to 30 parts by mass.
The content of the compound (B) in the layer (1-3) may be within a range in which the function of the layer (1-3) can be exhibited. The content of compound (B) in layer (1-3) is, for example, 0.01 to 99 parts by mass when the total content of compound (A) and compound (B) is 100 parts by mass. , Since the driving voltage of the light emitting device of the present disclosure is lower, it is preferably 0.05 to 90 parts by mass, more preferably 0.1 to 70 parts by mass, and still more preferably 0.5 to 50 parts by mass. , particularly preferably 1 to 30 parts by mass, particularly preferably 2 to 20 parts by mass.

In layer (1-3), compound (A), compound (B) and the first compound preferably interact physically, chemically or electrically. This interaction makes it possible, for example, to improve or tune the light emitting properties, charge transport properties or charge injection properties of layers (1-3), resulting in lower driving voltages of the light emitting device of the present disclosure.

In the layer (1-3), taking the light-emitting material as an example, the first compound, the compound (A), and the compound (B) electrically interact, and the first compound to the compound (A) Efficient transfer of electric energy and efficient transfer of electric energy from compound (A) to compound (B) can cause compound (B) to emit light more efficiently, and the light-emitting device of the present disclosure drive voltage is lower.

From the above point of view, in the layer (1-3), the driving voltage of the light emitting device of the present disclosure is lower, so the first compound has a hole injection property, a hole transport property, an electron injection property, and an electron transport property. It is more preferable to have at least one selected function.
From the above point of view, in the layer (1-3), the driving voltage of the light emitting device of the present disclosure is lower, so the compound (A) has a hole injection property, a hole transport property, an electron injection property, and an electron transport property. It is more preferable to have at least one selected function.
From the above viewpoint, in the layer (1-3), the driving voltage of the light-emitting device of the present disclosure becomes lower, so the compound (B) more preferably has light-emitting properties.
From the above point of view, in the layer (1-3), the lowest excited singlet state (S ₁ ) of the first compound has a lower driving voltage of the light emitting device of the present disclosure, so the lowest excited singlet state of the compound (A) An energy level higher than the excited singlet state (S ₁ ) is preferred.
From the above point of view, in the layer (1-3), the lowest excited singlet state (S ₁ ) of the first compound has a lower driving voltage of the light emitting device of the present disclosure, so the lowest excited singlet state of the compound (B) An energy level higher than the excited singlet state (S ₁ ) is preferred.
From the above viewpoint, in the layer (1-3), the lowest excited singlet state (S ₁ ) of the compound (A) has a lower driving voltage of the light emitting device of the present disclosure, so the lowest singlet state of the compound (B) An energy level higher than the excited singlet state (S ₁ ) is preferred.
From the above point of view, in the layer (1-3), the lowest excited triplet state (T ₁ ) of the first compound has a lower driving voltage of the light emitting device of the present disclosure, so the lowest excited triplet state of the compound (A) An energy level higher than the excited triplet state (T ₁ ) is preferred.
From the above point of view, in the layer (1-3), the lowest excited triplet state (T ₁ ) of the first compound has a lower driving voltage of the light emitting device of the present disclosure, so the lowest excited triplet state of the compound (B) An energy level higher than the excited triplet state (T ₁ ) is preferred.
From the above point of view, in the layer (1-3), the lowest excited triplet state (T ₁ ) of the compound (A) is lower than the driving voltage of the light-emitting device of the present disclosure, so the lowest triplet state of the compound (B) is An energy level higher than the excited triplet state (T ₁ ) is preferred.

The first compound preferably exhibits solubility in a solvent capable of dissolving the compound (B) and the compound (A) because the light-emitting device of the present disclosure can be produced by a wet method. .

In the layers (1-2) and (1-3), the first compound is preferably a host material, an assist dopant material, or a dopant material because the driving voltage of the light emitting device of the present disclosure is lower, A host material or an assist dopant material is more preferred, and a host material is even more preferred.
In the layers (1-1) and (1-3), the compound (A) is preferably a host material, an assist dopant material, or a dopant material because the driving voltage of the light-emitting device of the present disclosure becomes lower.
In the layers (1-1) and (1-3), the metal complex represented by formula (1) is used as a host material, an assist dopant material, or a dopant material because the driving voltage of the light emitting device of the present disclosure is lower. , more preferably an assist dopant material or a dopant material, and even more preferably an assist dopant material.
In the layers (1-1) and (1-3), the polymer compound (A) can be a host material, an assist dopant material, or a dopant material because the driving voltage of the light emitting device of the present disclosure is lower. It is preferably a host material or an assist dopant material, more preferably an assist dopant material.
In the layer (1-1) and the layer (1-3), the polymer compound (A) may have at least one function selected from a host material, an assist dopant material and a dopant material. , an assist dopant material and a dopant material, or may have three functions of a host material, an assist dopant material and a dopant material.
In the first layer (for example, layers (1-1) to (1-3)), the compound (B) is a host material, an assist dopant material, or Preferably, it is a dopant material.
In the first layer (eg, layer (1-1) to layer (1-3)), the low-molecular-weight compound (B) lowers the driving voltage of the light-emitting device of the present disclosure. It is preferably a material or dopant material, more preferably an assist dopant material or dopant material, and even more preferably a dopant material.
In the first layer (eg, layer (1-1) to layer (1-3)), the polymer compound (B) lowers the driving voltage of the light emitting device of the present disclosure, so the host material, the assist dopant It is preferably a material or a dopant material, more preferably a host material or a dopant material, even more preferably a dopant material.
In the first layer (eg, layers (1-1) to (1-3)), the polymer compound (B) has at least one function of a host material, an assist dopant material, and a dopant material. It may have at least two functions of a host material, an assist dopant material, and a dopant material, and has three functions of a host material, an assist dopant material, and a dopant material. good too.

In the light emitting device of the present disclosure, the host material is preferably a material that physically, chemically or electrically interacts with the assist dopant material. In the light emitting device of the present disclosure, the host material is preferably a material that physically, chemically or electrically interacts with the dopant material. In the light emitting device of the present disclosure, the assist dopant material is preferably a material that physically, chemically or electrically interacts with the dopant material. In the light-emitting device of the present disclosure, the host material, assisting dopant material, and dopant material preferably interact physically, chemically, or electrically. These interactions make it possible, for example, to improve or tune the light emitting properties, charge transport properties or charge injection properties of the light emitting devices of the present disclosure, resulting in lower driving voltages of the light emitting devices of the present disclosure.

In the light-emitting device of the present disclosure, if the light-emitting material is described as an example, the host material, the assisting dopant material, and the dopant material electrically interact to efficiently transfer electrical energy from the host material to the assisting dopant material, and further By efficiently transferring electrical energy from the assisting dopant material to the dopant material, the dopant material can emit light more efficiently, resulting in a lower driving voltage for the light emitting device of the present disclosure.

From the above viewpoint, in the light-emitting element of the present disclosure, the driving voltage of the light-emitting element of the present disclosure is lower, so the host material is at least selected from hole injection properties, hole transport properties, electron injection properties, and electron transport properties. It is more preferable to have one function.
From the above viewpoint, in the light-emitting device of the present disclosure, the driving voltage of the light-emitting device of the present disclosure is lower, so the assist dopant material is selected from hole injection properties, hole transport properties, electron injection properties, and electron transport properties. More preferably, it has at least one function.
From the above viewpoint, in the light-emitting device of the present disclosure, the driving voltage of the light-emitting device of the present disclosure is lower, so the dopant material preferably has light-emitting properties.
From the above viewpoint, in the light-emitting device of the present disclosure, the lowest excited singlet state (S ₁ ) of the host material has a lower driving voltage of the light-emitting device of the present disclosure, so the lowest excited singlet state of the assist dopant material An energy level higher than (S ₁ ) is preferred.
From the above viewpoint, in the light-emitting element of the present disclosure, the lowest excited singlet state (S ₁ ) of the host material has a lower driving voltage of the light-emitting element of the present disclosure, so the lowest excited singlet state of the dopant material ( S ₁ ) is preferably at a higher energy level.
From the above point of view, in the light-emitting device of the present disclosure, the lowest excited singlet state (S ₁ ) of the assist dopant material has a lower driving voltage for the light-emitting device of the present disclosure, so the lowest excited singlet state of the dopant material An energy level higher than (S ₁ ) is preferred.
From the above viewpoint, in the light-emitting device of the present disclosure, the lowest excited triplet state (T ₁ ) of the host material has a lower driving voltage of the light-emitting device of the present disclosure, so the lowest excited triplet state of the assist dopant material An energy level higher than (T ₁ ) is preferred.
From the above viewpoint, in the light-emitting device of the present disclosure, the lowest excited triplet state (T ₁ ) of the host material has a lower driving voltage for the light-emitting device of the present disclosure, so the lowest excited triplet state of the dopant material ( T ₁ ) is preferably a higher energy level.
From the above point of view, in the light-emitting device of the present disclosure, the lowest excited triplet state (T ₁ ) of the assist dopant material has a lower driving voltage for the light-emitting device of the present disclosure, so the lowest excited triplet state of the dopant material An energy level higher than (T ₁ ) is preferred.

In the light emitting device of the present disclosure, when the first layer is a layer containing an assist dopant material and a dopant material, the total content of the assist dopant material and the dopant 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 the present disclosure, when the first layer is a layer containing an assist dopant material and a dopant material, the total content of the assist dopant material and the dopant material in the first layer is, for example, the first It may be 0.01 to 100% by mass based on the total amount of the layer, and it is preferably 0.1 to 99% by mass, more preferably 0.1 to 99% by mass, because the driving voltage of the light-emitting device of the present disclosure is lower. 5 to 90% by mass, more preferably 1 to 70% by mass, particularly preferably 5 to 50% by mass, particularly preferably 10 to 30% by mass.
In the light-emitting device of the present disclosure, when the first layer is a layer containing an assist dopant material and a dopant material, the content of the dopant material in the first layer is such that the first layer functions as It is acceptable as long as it is within the range of In the light emitting device of the present disclosure, when the first layer is a layer containing an assist dopant material and a dopant material, the content of the dopant material in the first layer is the total content of the assist dopant material and the dopant material. When the amount is 100 parts by mass, for example, it is 0.01 to 99 parts by mass, and the driving voltage of the light emitting device of the present disclosure is lower, so it is preferably 0.05 to 90 parts by mass, more preferably It is 0.1 to 70 parts by mass, more preferably 0.5 to 50 parts by mass, particularly preferably 1 to 30 parts by mass, and most preferably 2 to 20 parts by mass.

In the light emitting device of the present disclosure, when the first layer is a layer containing a host material and a dopant material, the total content of the host material and the dopant material in the first layer is Any range is acceptable as long as the function can be achieved. In the light emitting device of the present disclosure, when the first layer is a layer containing a host material and a dopant material, the total content of the host material and the dopant material in the first layer is, for example, the first layer may be 0.1 to 100% by mass based on the total amount of, and the driving voltage of the light-emitting device of the present disclosure is lower, so it is preferably 1 to 99.9% by mass, more preferably 10 to 99. 9% by mass, more preferably 30 to 99% by mass, particularly preferably 50 to 95% by mass, particularly preferably 70 to 90% by mass.
In the light emitting device of the present disclosure, when the first layer is a layer containing a host material and a dopant material, the content of the dopant material in the first layer functions as the first layer. Any range is acceptable. In the light emitting device of the present disclosure, when the first layer is a layer containing a host material and a dopant material, the content of the dopant material in the first layer is the total content of the host material and the dopant material. When it is 100 parts by mass, it is, for example, 0.01 to 99 parts by mass, and the driving voltage of the light emitting device of the present disclosure is lower, so it is preferably 0.05 to 90 parts by mass, more preferably 0.05 part by mass. It is 1 to 70 parts by mass, more preferably 0.2 to 50 parts by mass, particularly preferably 0.5 to 30 parts by mass, and most preferably 1 to 10 parts by mass.

In the light emitting device of the present disclosure, when the first layer is a layer containing a host material, an assist dopant material and a dopant material, the total content of the host material, the assist dopant material and the dopant material in the first layer may be within a range in which the function as the first layer is exhibited. In the light emitting device of the present disclosure, when the first layer is a layer containing a host material, an assist dopant material and a dopant material, the total content of the host material, the assist dopant material and the dopant material in the first layer For example, it may be 1 to 100% by mass based on the total amount of the first layer, and is preferably 10 to 100% by mass, more preferably 30 to 100% by mass, 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 the present disclosure, when the first layer is a layer containing a host material, an assist dopant material, and a dopant material, the total content of the assist dopant material and the dopant material in the first layer is It is sufficient if it is within the range where the function as one layer is exhibited. In the light-emitting device of the present disclosure, when the first layer is a layer containing a host material, an assist dopant material, and a dopant material, the total content of the assist dopant material and the dopant material in the first layer is When the total content of the material, the assist dopant material and the dopant material is 100 parts by mass, for example, it is 0.01 to 99.9 parts by mass, and the driving voltage of the light emitting device of the present disclosure is lower, so it is preferable. is 0.1 to 99 parts by mass, more preferably 0.5 to 90 parts by mass, still more preferably 1 to 70 parts by mass, particularly preferably 5 to 50 parts by mass, particularly preferably 10 ~30 parts by mass.
In the light emitting device of the present disclosure, when the first layer is a layer containing a host material, an assist dopant material, and a dopant material, the total content of the dopant materials in the first layer is It is sufficient if it is within the range where the function of In the light-emitting device of the present disclosure, when the first layer is a layer containing a host material, an assist dopant material, and a dopant material, the content of the dopant material in the first layer is When the total content is 100 parts by mass, for example, it is 0.01 to 99 parts by mass, and the driving voltage of the light emitting device of the present disclosure is lower, so it is preferably 0.05 to 90 parts by mass, It is more preferably 0.1 to 70 parts by mass, still more preferably 0.5 to 50 parts by mass, particularly preferably 1 to 30 parts by mass, and most preferably 2 to 20 parts by mass.

The assist dopant material preferably exhibits solubility in a solvent capable of dissolving the dopant material, since the light-emitting device of the present disclosure can be produced by a wet method. The host material preferably exhibits solubility in a solvent capable of dissolving the assist dopant material and the dopant material, since the light-emitting device of the present disclosure can be produced by a wet method.

[First composition]
The first layer 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 layer is selected from the group consisting of a compound (B), a compound (A), a first compound, a hole-transporting material, a hole-injecting material, an electron-transporting material, an electron-injecting material, a light-emitting material, and an 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, the hole-injecting material, the electron-transporting material, the electron-injecting material, and the light-emitting material are different from the compound (B).
The first composition contains the compound (B), the compound (A), the first compound, the hole-transporting material, the hole-injecting material, the electron-transporting material, the electron-injecting material, the light-emitting material, and the antioxidant, respectively. , may be contained singly, or two or more kinds thereof may be contained.
In the first composition, the compound (B), the compound (A), the first compound, the hole-transporting material, the hole-injecting material, the electron-transporting material, the electron-injecting material, the light-emitting material, and the antioxidant The amount may be within a range in which the function as the first composition is exhibited. In the first composition, the compound (B), the compound (A), the first compound, the hole-transporting material, the hole-injecting material, the electron-transporting material, the electron-injecting material, the light-emitting material, and the antioxidant The amount may be, for example, 1 to 100% by mass, 10 to 100% by mass, or 30 to 100% by mass based on the total amount of the first composition, more preferably It may be 50 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);
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 usually 1 to 10,000 parts by mass based on 100 parts by mass of the compound (B).
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 based on 100 parts by mass of the compound (B).
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 each set to 100 parts by mass of the content of the compound (B). In that case, it is usually 1 to 10,000 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-injecting material or the electron-injecting material may be doped with ions. For example, if the hole-injecting material or electron-injecting material comprises 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 or the electron injection material include, for example, anions for the hole injection material and cations for the electron injection material. 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 structural units represented by the above formula (Y) and/or structural units represented by the above formula (X).
When the first composition contains a luminescent material, the content of the luminescent material is usually 1 to 10,000 parts by mass based on 100 parts by mass of the compound (B).
A luminescent material may be used individually by 1 type, or may use 2 or more types together.

(Antioxidant)
The antioxidant is soluble in the same solvent as the compound (B) and compound (A), and may be any compound that does not inhibit light emission and charge transport. mentioned.
When the first composition contains an antioxidant, the content of the antioxidant is usually 0.00001 to 10 parts by mass based on 100 parts by mass of the compound (B).
Antioxidants may be used singly or in combination of two or more.

[First ink]
The first layer can be formed using, for example, a composition containing the compound (B) and a solvent (hereinafter also referred to as "first ink").
The first ink may contain one type of compound (B) and solvent, or two or more types thereof.
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) and compound (A) 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 contains at least one selected from the group consisting of a compound (A), a first compound, a hole-transporting material, a hole-injecting material, an electron-transporting material, an electron-injecting material, a luminescent material and an antioxidant. It may further contain:
The first ink may contain one kind of hole transport material, hole injection material, electron transport material, electron injection material, light emitting material and antioxidant, respectively, or contain two or more kinds. 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 content of the hole-transporting material, electron-transporting material, hole-injecting material, electron-injecting material, and light-emitting material that the first ink may further contain is 100 parts by mass of the content of compound (B). , 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 to 10 parts by mass when the content of the compound (B) is 100 parts by mass.

<Second layer>
In the light-emitting device of the present disclosure, the second layer includes a low-molecular-weight compound represented by formula (ET-1), a low-molecular-weight compound represented by formula (ET-2), and formula (ET-1) A structural unit having a group obtained by removing one or more hydrogen atoms from the low-molecular-weight compound represented by the formula (ET-2), a structural unit having a group obtained by removing one or more hydrogen atoms from the low-molecular-weight compound represented by the formula (ET-2), A polymer compound containing at least one structural unit selected from the group consisting of a structural unit represented by (X) and a structural unit represented by formula (Y) (hereinafter referred to as "second layer high It is a layer containing at least one compound (hereinafter also referred to as a "second layer compound") selected from the group consisting of (also referred to as "a molecular compound"). That is, the second layer is a layer containing the compound of the second layer, the low-molecular-weight compound represented by the formula (ET-1), the low-molecular-weight compound represented by the formula (ET-2) and the second layer It is a layer containing at least one compound selected from the group consisting of two layers of polymeric compounds.
The second layer may contain only one type of compound for the second layer, or may contain two or more types.

The content of the compound of the second layer in the second layer may be within a range in which the function as the second layer is exhibited. The total content of the compounds of the second layer in the second layer may be, for example, 1 to 100% by mass based on the total amount of the second layer, and the driving voltage of the light emitting device of the present disclosure is higher. Since it becomes lower, 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 to 100% by mass, particularly preferably 90 to 100% by mass.

[Second layer compound]
The compound of the second layer is selected from the group consisting of a low-molecular-weight compound represented by formula (ET-1), a low-molecular-weight compound represented by formula (ET-2), and a high-molecular-weight compound for the second layer. is at least one

(Low-molecular compound represented by formula (ET-1))
nE1 is preferably an integer of 1-4, more preferably 1 or 2.

The aromatic hydrocarbon group represented by Ar ^E1 is preferably monocyclic or bicyclic to hexacyclic aromatic hydrocarbons, since the driving voltage of the light-emitting element of the present disclosure is lower. A group excluding one or more hydrogen atoms directly bonded to the constituent atoms, more preferably a monocyclic, bicyclic or tricyclic aromatic hydrocarbon directly bonded to the ring-constituting atoms A group from which one or more hydrogen atoms have been removed, more preferably a group from benzene, naphthalene, anthracene, phenanthrene, dihydrophenanthrene or fluorene from which one or more hydrogen atoms directly bonded to atoms constituting a ring have been removed. , Particularly preferably, a group obtained by removing one or more hydrogen atoms directly bonded to the atoms constituting the ring from benzene, naphthalene, phenanthrene, dihydrophenanthrene or fluorene, and these groups may have substituents. good.
The heterocyclic group represented by Ar ^E1 preferably comprises a ring composed of a monocyclic or bicyclic to hexacyclic heterocyclic compound because the driving voltage of the light-emitting device of the present disclosure is lower. A group obtained by removing one or more hydrogen atoms directly bonded to an atom, more preferably a hydrogen atom directly bonded to an atom constituting a ring from a monocyclic, bicyclic or tricyclic heterocyclic compound. A group excluding one or more, more preferably pyridine, diazabenzene, triazine, azanaphthalene, diazanaphthalene, carbazole, dibenzofuran, dibenzothiophene, phenoxazine, phenothiazine, 9,10-dihydroacridine or 5,10- A group obtained by removing one or more hydrogen atoms directly bonded to a ring-constituting atom (preferably a carbon atom or a nitrogen atom, more preferably a carbon atom) from dihydrophenazine, particularly preferably pyridine, diazabenzene, triazine, A group obtained by removing one or more 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, and The group may have a substituent.
Ar ^E1 is preferably a group obtained by removing one or more hydrogen atoms directly bonded to ring-constituting atoms from benzene, naphthalene, fluorene, phenanthrene or carbazole, and this group is a substituent other than R ^E1 . may have.

Substituents other than R ^E1 that Ar ^E1 may have include 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, and an aryloxy group. groups, amino groups, substituted amino groups, alkenyl groups, cycloalkenyl groups, alkynyl groups, cycloalkynyl groups, carboxyl groups and groups represented by formula (ES-3).

—O—(C _n′ H _2n′ O) _nx —C _m′ H _2m′+1 (ES-3)
[In the formula, n', m' and nx each independently represent an integer of 1 or more. ]

nE3 is usually an integer of 0-10, preferably an integer of 0-8, more preferably an integer of 0-2.
aE1 is usually an integer of 1-10, preferably an integer of 1-5, more preferably 1 or 2.
bE1 is usually an integer of 0-10, preferably an integer of 0-4, more preferably 0 or 1.
mE1 is generally an integer of 1 to 5, preferably 1 or 2, more preferably 1.

When R ^E3 is —OR ^E3 ', the group represented by formula (ES-1) is the group represented below.
-OR ^E3 '-{(Q ^E1 ) _nE3 -Y ^E1 (M ^E1 ) _aE1 (Z ^E1 ) _bE1 } _mE1

R ^E3 is preferably a hydrocarbon group or a heterocyclic group, more preferably an aromatic hydrocarbon group or an aromatic heterocyclic group, and still more preferably an aromatic hydrocarbon group. good too.
Examples of the substituent that R ^E3 may have include an alkyl group, a cycloalkyl group, an aryl group, a monovalent heterocyclic group and a group represented by the formula (ES-3). Groups represented by 3) are preferred, and these groups may further have a substituent.

Q ^E1 is preferably an alkylene group, an arylene group or an oxygen atom, more preferably an alkylene group or an oxygen atom, and these groups may have a substituent.

Y ^E1 is preferably -CO ₂ ^- , -SO ₂ ^- or -PO ₃ ^2- , more preferably -CO ₂ ^- .
Alkali metal cations represented by M ^E1 include, for example, Li ⁺ , Na ⁺ , K ⁺ , Rb ⁺ and Cs ⁺ , preferably K ⁺ , Rb ⁺ or Cs ⁺ , more preferably Cs ⁺ .
Alkaline earth metal cations represented by M ^E1 include, for example ^, Be ²⁺ , Mg ²⁺ , Ca 2+ , Sr ²⁺ , Ba ²⁺ , Mg ²⁺ , Ca ²⁺ , Sr ²⁺ Or Ba ²⁺ is preferred, and Ba ²⁺ is more preferred.
M ^E1 is preferably an alkali metal cation or an alkaline earth metal cation, more preferably an alkali metal cation.
Z ^E1 includes F ⁻ , Cl ⁻ , Br ⁻ , I ⁻ , OH ⁻ , B(R ^E4 ) ₄ ⁻ , R ^E4 SO ₃ ⁻ , R ^E4 C
OO ^- or NO ₃ ^- is preferred, F ^- , Cl ^- , Br ^- , I ^- , OH ^- , R ^E4 SO ₃ ^- or R ^E4 CO
O ^- is preferred. R ^E4 is preferably an alkyl group.

Examples of the group represented by formula (ES-1) include groups represented by the following formulas.

[In the formula, M ⁺ represents Li ⁺ , Na ⁺ , K ⁺ , Cs ⁺ or N(CH ₃ ) ₄ ⁺ . When multiple M ⁺ are present, they may be the same or different. ]

(Low-molecular compound represented by formula (ET-2))
nE2 is generally an integer of 1-4, preferably 1 or 2.

Examples and preferred ranges of the aromatic hydrocarbon group represented by Ar ^E2 are the same as examples and preferred ranges of the aromatic hydrocarbon group represented by Ar ^E1 .
Examples and preferred ranges of the heterocyclic group represented by Ar ^E2 are the same as examples and preferred ranges of the divalent heterocyclic group represented by Ar ^E1 .
Examples and preferred ranges for Ar ^E2 are the same as those for Ar ^E1 .
The substituents other than R ^E2 that Ar ^E2 may have are the same as the substituents other than R ^E1 that Ar ^E1 may have.

nE4 is generally an integer of 0-10, preferably an integer of 0-8, more preferably an integer of 0-2.
aE2 is usually an integer of 1-10, preferably an integer of 1-5, more preferably 1 or 2.
bE2 is usually an integer of 0-10, preferably an integer of 0-4, more preferably 0 or 1.
mE2 is generally an integer of 1 to 5, preferably 1 or 2, more preferably 1.

When R ^E5 is —OR ^E5 ', the group represented by formula (ES-2) is the group represented below.
-OR ^E5 '-{(Q ^E1 ) _nE3 -Y ^E1 (M ^E1 ) _aE1 (Z ^E1 ) _bE1 } _mE1

R ^E5 is preferably a hydrocarbon group or a heterocyclic group, more preferably an aromatic hydrocarbon group or an aromatic heterocyclic group, and still more preferably an aromatic hydrocarbon group. good too.

Examples of the substituent that R ^E5 may have include an alkyl group, a cycloalkyl group, an aryl group, a monovalent heterocyclic group and a group represented by the formula (ES-3). Groups represented by 3) are preferred, and these groups may further have a substituent.

Q ^E2 is preferably an alkylene group, an arylene group or an oxygen atom, more preferably an alkylene group or an oxygen atom, and these groups may have a substituent.

Y ^E2 is preferably -C ⁺ R ^E6 ₂ , -N ⁺ R ^E6 ₃ , -P ⁺ R ^E6 ₃ or S ⁺ R ^E6 ₂ , and -N ⁺
R ^E6 ₃ is more preferred. R ^E6 is preferably a hydrogen atom, an alkyl group or an aryl group, more preferably a hydrogen atom or an alkyl group, and these groups may have a substituent.
M ^E2 includes F ⁻ , Cl ⁻ , Br ⁻ , I ⁻ , B(R ^E7 ) ₄ ⁻ , R ^E7 SO ₃ ⁻ , R ^E7 COO ⁻ ,
BF ₄ ^- or SbF ^6- is preferred, and Br ^- , I ^- , B(R ^E7 ) ₄ ^- , R ^E7 COO ^- or SbF ^6-
is more preferred. R ^E7 is preferably an optionally substituted alkyl group.
Alkali metal cations represented by Z ^E2 include, for example, Li ⁺ , Na ⁺ , K ⁺ , Rb ⁺ and Cs ⁺ , with Li ⁺ , Na ⁺ and K ⁺ being preferred.
Alkaline earth metal cations represented by Z ^E2 include, for example, Be ²⁺ , Mg ²⁺ , Ca ²⁺ , Sr ²⁺ and Ba ²⁺ , preferably Mg ²⁺ or Ca ²⁺ .
Z ^E2 is preferably an alkali metal cation.

Examples of the group represented by formula (ES-2) include groups represented by the following formulas.

[In the formula, X ^- represents F ^- , Cl ^- , Br ^- , I ^- , B(C ₆ H ₅ ) ₄ ^- , CH ₃ COO ^- or CF ₃ SO ₃ ^- . When multiple X ^- are present, they may be the same or different. ]

Examples of the low-molecular-weight compound represented by Formula (ET-1) and the low-molecular-weight compound represented by Formula (ET-2) include the compounds shown below.

(Polymer compound of the second layer)
The polymer compound of the second layer is a structural unit having a group obtained by removing one or more hydrogen atoms from the low molecular weight compound represented by the formula (ET-1) (hereinafter also referred to as "structural unit (ET-1)" ), a structural unit having a group obtained by removing one or more hydrogen atoms from the low-molecular compound represented by formula (ET-2) (hereinafter also referred to as “structural unit (ET-2)”), formula ( A polymer compound containing at least one structural unit selected from the group consisting of structural units represented by X) and structural units represented by formula (Y).
In the polymer compound of the second layer, the structural unit (ET-1), the structural unit (ET-2), the structural unit represented by the formula (X) and the structural unit represented by the formula (Y) are each , one type may be contained in the polymer compound of the second layer, or two or more types may be contained.

・Constituent unit (ET-1)
Structural unit (ET-1) is preferably represented by formula (ET-1) because it is easy to synthesize the polymer compound of the second layer and the driving voltage of the light-emitting device of the present disclosure is lower. A structural unit having a group obtained by removing 1 to 5 hydrogen atoms from the low-molecular compound represented by the formula (ET-1), more preferably 1 to 3 hydrogen atoms from the low-molecular compound represented by the formula (ET-1) and more preferably a structural unit having a group obtained by removing one or two hydrogen atoms from the low-molecular-weight compound represented by the formula (ET-1), particularly Preferred is a structural unit having a group obtained by removing two hydrogen atoms from the low-molecular-weight compound represented by formula (ET-1).

Structural unit (ET-1) is a structural unit represented by formula (ET-1) since it further lowers the driving voltage of the light-emitting device of the present disclosure.

[In the formula, nE1, Ar ^E1 and R ^E1 have the same meanings as described above. ]

・Constituent unit (ET-2)
Structural unit (ET-2) is preferably represented by formula (ET-2) because it is easy to synthesize the polymer compound of the second layer and the driving voltage of the light emitting device of the present disclosure is lower. A structural unit having a group obtained by removing 1 to 5 hydrogen atoms from the low-molecular-weight compound represented by the formula (ET-2), more preferably 1 to 3 hydrogen atoms from the low-molecular-weight compound represented by the formula (ET-2) and more preferably a structural unit having a group obtained by removing one or two hydrogen atoms from the low-molecular-weight compound represented by the formula (ET-2), particularly Preferred is a structural unit having a group obtained by removing two hydrogen atoms from the low-molecular-weight compound represented by the formula (ET-2).

Structural unit (ET-2) is a structural unit represented by formula (ET-2) because the driving voltage of the light-emitting device of the present disclosure is further lowered.

[In the formula, nE2, Ar ^E2 and R ^E2 have the same meanings as described above. ]

Examples of the structural unit (ET-1) or structural unit (ET-2) include structural units represented by formulas (ET-31) to (ET-38).

Since the polymer compound of the second layer has a lower driving voltage of the light emitting device of the present disclosure, the structural unit (ET-1), the structural unit (ET-2), and the structural unit represented by the formula (Y) It is preferably a polymer compound containing at least one structural unit selected from the group consisting of at least one selected from the group consisting of structural units (ET-1) and structural units (ET-2) A polymer compound containing a structural unit is more preferred, and a polymer compound containing a structural unit (ET-1) is even more preferred.

When the polymer compound of the second layer contains the structural unit (ET-1), the content of the structural unit (ET-1) is within a range where the function of the polymer compound of the second layer is exhibited. Just do it. When the polymer compound of the second layer contains the structural unit (ET-1), the content of the structural unit (ET-1) is the total content of the structural units contained in the polymer compound of the second layer. For example, it is 0.1 to 100 mol%, and the driving voltage of the light emitting device of the present disclosure is lower, so it is preferably 1 to 100 mol%, more preferably 10 to 100 mol%. , more preferably 30 to 100 mol %, particularly preferably 50 to 100 mol %, particularly preferably 70 to 100 mol %, and even more preferably 90 to 100 mol %.

When the polymer compound of the second layer contains the structural unit (ET-2), the content of the structural unit (ET-2) is within a range where the function of the polymer compound of the second layer is exhibited. Just do it. When the polymer compound of the second layer contains the structural unit (ET-2), the content of the structural unit (ET-2) is the total content of the structural units contained in the polymer compound of the second layer. For example, it is 0.1 to 100 mol%, and the driving voltage of the light emitting device of the present disclosure is lower, so it is preferably 1 to 100 mol%, more preferably 10 to 100 mol%. , more preferably 30 to 100 mol %, particularly preferably 50 to 100 mol %, particularly preferably 70 to 100 mol %, and even more preferably 90 to 100 mol %.

When the polymer compound of the second layer contains the structural unit represented by formula (Y), the content of the structural unit represented by formula (Y) is such that the function as the polymer compound of the second layer is It is acceptable as long as it is within the range where it can be played. When the polymer compound of the second layer contains the structural unit represented by formula (Y), the content of the structural unit represented by formula (Y) is the composition contained in the polymer compound of the second layer It is, for example, 0.1 to 100 mol % with respect to the total content of the units, and is preferably 1 to 100 mol %, more preferably 5, because the driving voltage of the light-emitting device of the present disclosure is lower. to 95 mol%, more preferably 10 to 90 mol%, particularly preferably 20 to 80 mol%, particularly preferably 30 to 70 mol%, and even more preferably 40 to 60 mol%. be.

When the polymer compound of the second layer contains the structural unit represented by formula (X), the content of the structural unit represented by formula (X) is such that the function as the polymer compound of the second layer is It is acceptable as long as it is within the range where it can be played. When the polymer compound of the second layer contains the structural unit represented by formula (X), the content of the structural unit represented by formula (X) is the composition contained in the polymer compound of the second layer It is, for example, 0.01 to 100 mol % relative to the total content of the units, and is preferably 0.05 to 99 mol %, more preferably 0.05 to 99 mol %, because the driving voltage of the light-emitting device of the present disclosure is lower. is 0.1 to 90 mol%, more preferably 0.1 to 70 mol%, particularly preferably 0.2 to 500 mol%, particularly preferably 0.5 to 30 mol%, Particularly, it is more preferably 1 to 10 mol %.

The structural unit (ET-1), the structural unit (ET-2), the structural unit formula represented by the formula (Y), and the structural unit represented by the formula (X), which may be contained in the polymer compound of the second layer The total content of the constituent units may be within a range in which the function of the polymer compound of the second layer can be exhibited. The structural unit (ET-1), the structural unit (ET-2), the structural unit formula represented by the formula (Y), and the structural unit represented by the formula (X), which may be contained in the polymer compound of the second layer The total content of the structural units is, for example, 0.1 to 100 mol% with respect to the total content of the structural units contained in the polymer compound of the second layer. Since the voltage becomes lower, it is preferably 1 to 100 mol%, more preferably 10 to 100 mol%, still more preferably 30 to 100 mol%, particularly preferably 50 to 100 mol%, It is particularly preferably 70 to 100 mol %, and more preferably 90 to 100 mol %.

Examples of polymer compounds for the second layer include polymer compounds EP-1 to EP-16 shown in Table 4. Here, "other" means structural units other than structural units (ET-1), structural units (ET-2), structural units represented by formula (X), and structural units represented by formula (Y). means

[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 of the second layer may be a block copolymer, a random copolymer, an alternating copolymer, or a graft copolymer. is preferably a copolymer obtained by copolymerizing the raw material monomers.
The polystyrene equivalent number average molecular weight of the polymer compound of the second layer is preferably 5×10 ³ to 1×10 ⁶ , more preferably 1×10 ⁴ to 5×10 ⁵ , still more preferably 1×10 4 to 5×10 5 . .5×10 ⁴ to 1×10 ⁵ .

[Method for producing polymer compound for second layer]
The polymer compound of the second layer, for example, JP-A-2009-239279, JP-A-2012-033845, JP-A-2012-216821, JP-A-2012-216822, JP-A-2012-216815 It can be synthesized according to the method described in the publication.

[Second composition]
The second layer contains the compound of the second layer and at least one selected from the group consisting of hole transport materials, hole injection materials, electron transport materials, electron injection materials, light emitting materials and antioxidants. It may be a layer containing a composition (hereinafter also referred to as “second composition”). In the second layer, the hole-transporting material, hole-injecting material, electron-transporting material, electron-injecting material and emissive material are different from the compound of the second layer.
The second composition contains one of each of the compound of the second layer, the hole-transporting material, the hole-injecting material, the electron-transporting material, the electron-injecting material, the light-emitting material, and the antioxidant. may be contained, or two or more kinds may be contained.
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 total content of the compound of the second layer, the hole transport material, the hole injection material, the electron transport material, the electron injection material, the light emitting material and the antioxidant is It is sufficient if it is within the range where the function as In the second composition, the total content of the compound of the second layer, the hole-transporting material, the hole-injecting material, the electron-transporting material, the electron-injecting material, the light-emitting material and the antioxidant is, for example, the second Based on the total amount of the composition, it may be 1 to 100% by mass, may be 10 to 100% by mass, may be 30 to 100% by mass, and more preferably 50 to 100% by mass. may be from 70 to 100% by mass, or from 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 each based on the content of the compound in the second layer being 100 parts by mass. , usually from 1 to 10,000 parts by mass. In the second composition, the content of the antioxidant is usually from 0.00001 to 10 parts by mass when the content of the compound in the second layer is 100 parts by mass.

[Second ink]
The second layer can be formed, for example, using a composition containing a compound of the second layer and a solvent (hereinafter also referred to as "second ink").
The second ink may contain one type of compound and solvent for the second layer, or two or more types 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.
The solvent contained in the second ink can laminate the second layer on the layer (e.g., the first layer) by utilizing the difference in solubility. Ethers, esters, nitrile compounds, nitro compounds, fluorinated alcohols, thiols, sulfides, sulfoxides, thioketones, amides and/or carboxylic acids. Specific examples of the solvent include methanol, ethanol, 2-propanol, 1-butanol, tert-butyl alcohol, acetonitrile, 1,2-ethanediol, N,N-dimethylformamide, dimethylsulfoxide, acetic acid, nitromethane, propylene carbonate. , pyridine, carbon disulfide, and mixed solvents of these solvents. When a mixed solvent is used, one or more solvents selected from water, alcohol, ether, ester, nitrile compound, nitro compound, fluorinated alcohol, thiol, sulfide, sulfoxide, thioketone, amide, and carboxylic acid, a chlorinated solvent, It may be a mixed solvent with one or more solvents selected from aromatic hydrocarbon solvents, aliphatic hydrocarbon solvents and ketone solvents.
In the second ink, the content of the solvent is usually 1000 to 10000000 parts by mass when the content of the compound in the second layer 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 comprise, respectively, are those of the first composition 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 content of the hole-transporting material, the electron-transporting material, the hole-injecting material, the electron-injecting material, and the light-emitting material, which the second ink may further include, is 100 times the content of the compound in the second layer. When expressed as parts by mass, it is usually 1 to 10,000 parts by mass. The content of the antioxidant that the second ink may further contain is usually 0.00001 to 10 parts by mass when the content of the compound in the second layer is 100 parts by mass.

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

The light-emitting device of the present disclosure has a low driving voltage.
The reason why the above effects are exhibited is presumed as follows, but is not limited thereto.

In the light-emitting device of the present disclosure, the second layer contains the compound of the second layer, so that the light-emitting properties, charge transport properties and/or charge injection properties of the second layer can be improved or adjusted. Furthermore, it is speculated that the driving voltage of the light-emitting device of the present disclosure is reduced by improving or adjusting the electron injection property from the cathode to the first layer by having the second layer of the light-emitting device of the present disclosure. be done.

In the light-emitting device of the present disclosure, the first layer is preferably a light-emitting layer (hereinafter referred to as "first light-emitting layer").
In the light-emitting device of the present disclosure, the second layer preferably includes a light-emitting layer (that is, a light-emitting layer separate from the first light-emitting layer, hereinafter referred to as a “second light-emitting layer”), an electron It is a transport layer or an electron injection layer, more preferably an electron transport layer or an electron injection layer, and still more preferably an electron transport layer.

In the light-emitting device of the present disclosure, the first layer and the second layer are preferably adjacent to each other because the driving voltage of the light-emitting device of the present disclosure is lower.

In the light-emitting device of the present disclosure, the second layer is the second light-emitting layer, the electron transport layer, or the electron transport layer provided between the cathode and the first layer because the driving voltage of the light-emitting device of the present disclosure is lower. It is preferably an injection layer, more preferably an electron-transporting layer or an electron-injecting layer provided between the cathode and the first layer, and an electron-transporting layer provided between the cathode and the first layer. It is even more preferable to have

In the light emitting device of the present disclosure, since the driving voltage of the light emitting device of the present disclosure is lower, at least one layer of a hole injection layer and a hole transport layer is further provided between the anode and the first layer. It is preferable to have
In the light-emitting device of the present disclosure, when the second layer is the second light-emitting layer provided between the cathode and the first layer, the driving voltage of the light-emitting device of the present disclosure is lower. It is preferable to further have at least one layer of an electron injection layer and an electron transport layer between the two layers.
In the light-emitting device of the present disclosure, when the second layer is an electron-transporting layer provided between the cathode and the first layer, the driving voltage of the light-emitting device of the present disclosure is lower. It is preferable to further have an electron injection layer between the layers.
In the light-emitting device of the present disclosure, when the second layer is an electron injection layer provided between the cathode and the first layer, the driving voltage of the light-emitting device of the present disclosure is lower. It is preferable to further have an electron transport layer between the first layer.

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

(D1) anode/first emitting layer (first layer)/electron transporting layer (second layer)/cathode (D2) anode/hole injection layer/first emitting layer (first layer)/ Electron transport layer (second layer)/cathode (D3) anode/hole injection layer/hole transport layer/first light emitting layer (first layer)/electron transport layer (second layer)/cathode ( D4) anode/hole-injection layer/hole-transport layer/first light-emitting layer (first layer)/electron-injection layer (second layer)/cathode (D5) anode/hole-injection layer/hole-transport layer/first light-emitting layer (first layer)/electron-transporting layer (second layer)/electron-injecting layer/cathode (D6) anode/hole-injecting layer/hole-transporting layer/first light-emitting layer ( first layer)/second light emitting layer/electron transport layer (second layer)/electron injection layer/cathode (D7) anode/hole injection layer/hole transport layer/second light emitting layer/first Emissive layer (first layer)/electron transport layer (second layer)/electron injection layer/cathode (D8) anode/first luminescent layer (first layer)/second luminescent layer (second layer)/cathode (D9) anode/hole injection layer/first light-emitting layer (first layer)/second light-emitting layer (second layer)/electron transport layer/cathode (D10) anode/positive Hole injection layer/first light emitting layer (first layer)/second light emitting layer (second layer)/electron injection layer/cathode (D11) anode/hole injection layer/first light emitting layer (second 1 layer)/second light emitting layer (first layer)/electron transport layer/electron injection layer/cathode (D12) 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 (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/first emitting layer (first layer)/electron injection layer (second layer)/cathode (D16) anode/hole injection layer/first emission layer (first layer)/electron transport layer/electron injection layer (second layer)/cathode (D17) anode/hole injection layer/hole transport layer/first emission layer ( first layer)/electron transport layer/electron injection layer (second layer)/cathode

In (D1) to (D17) above, "/" means that the layers before and after it are laminated adjacent to each other. For example, “first light-emitting layer (first layer)/electron-transporting layer (second layer)” means the first light-emitting layer (first layer) and the electron-transporting layer (second layer). means that are stacked adjacent to each other.

In the light emitting device of the present disclosure, two or more layers of the anode, hole injection layer, hole transport layer, light emitting layer, electron transport layer, electron injection layer, and cathode may each be provided, 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 the present disclosure, 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 to It is 1 μm, preferably 2 nm to 500 nm, more preferably 5 nm to 150 nm.

In the light-emitting element of the present disclosure, the order, number, and thickness of layers to be stacked may be adjusted in consideration of the driving voltage of the light-emitting element and the like.

[First light-emitting layer]
The first emissive 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 first 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 the present disclosure has a second light-emitting layer, and the electron injection layer and the electron transport layer described below are not the second layer, the second light-emitting layer is the second layer. is preferred.

[Hole transport layer]
A hole-transporting layer is a layer containing a hole-transporting material. The hole-transporting material contained in the hole-transporting layer includes, for example, the hole-transporting material that the first composition may contain. The hole-transporting material contained in the hole-transporting layer may be contained alone or in combination of two or more.

[Electron transport layer]
The electron-transporting layer is a second layer or a layer containing an electron-transporting material, preferably the second layer. 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 first 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 the present disclosure has an electron-transporting layer, and the second light-emitting layer described above and the electron-injecting layer described later are not the second layer, the electron-transporting layer is preferably the second layer. .

[Hole injection layer]
A 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 hole injection material that the first composition may contain. The hole injection material contained in the hole injection layer may be contained singly or in combination of two or more.

[Electron injection layer]
The electron injection layer is a second layer or a layer containing an electron injection material, preferably a layer containing an electron injection material. When the electron injection layer is a layer containing an electron injection material, examples of the electron injection material contained in the electron injection layer include the electron injection material that the first composition may contain. . The electron injection material contained in the electron injection layer may be contained singly or in combination of two or more.
When the light emitting device of this embodiment has an electron injection layer and the second light emitting layer and the electron transport layer are not the second layer, the electron injection layer may be the second layer. preferable.

[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 disclosure, the method for forming the first layer, the second layer, and the layers other than the first layer and the second layer may be, for example, vacuum A dry method such as a vapor 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 preferred because it facilitates the production of the light-emitting device of the present disclosure. 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.

The light-emitting device of the present disclosure 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.

Materials used to form a hole injection layer, materials used to form a light emitting layer, materials used to form a hole transport layer, materials used to form an electron transport layer, and electron injection in the manufacture of the light emitting device of the present disclosure When the materials used for forming the layers are soluble 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, the Dissolution of the material is preferably avoided. 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 element of the present disclosure is suitable as a light source for backlight of a liquid crystal display device, a light source for illumination, organic EL lighting, a display device such as a computer, a television, and a mobile terminal (e.g., an organic EL display and an organic EL television). can be used.

Hereinafter, one embodiment of the present disclosure will be described in more detail with reference to Examples, but the present disclosure 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.

NMR was measured by the following method.
5 to 10 mg of a measurement sample was added to about 0.5 mL of heavy chloroform (CDCl ₃ ), heavy tetrahydrofuran, heavy dimethylsulfoxide, heavy acetone, heavy N,N-dimethylformamide, heavy toluene, heavy methanol, heavy ethanol, heavy 2-propanol. Alternatively, it was dissolved in methylene dichloride and measured using an NMR device (manufactured by Agilent, trade name: INOVA300 or MERCURY 400VX).

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 and acquisition of compounds H1 to H3, compounds MC1 to MC3 and compounds B1 to B3>
Compounds H1 to H3 and compound B1 were manufactured by Luminescence Technology.
Compound MC1 and compound MC2 were synthesized according to the method described in JP-A-2013-147551.
Compound MC3 was synthesized according to the method described in JP-A-2015-038195.
Compound B2 and compound B3 were synthesized according to the method described in WO2019/004248.

The _ΔEST of compound B1 was 0.49 eV. The maximum peak wavelength of the emission spectrum of compound B1 at room temperature was 452 nm. The maximum peak half width of the emission spectrum of compound B1 at room temperature was 22 nm.

<Synthesis of Compounds M1 to M12>
Compound M1 was synthesized according to the method described in WO2015/145871.
Compound M2 was synthesized according to the method described in WO2013/146806.
Compound M3 was synthesized according to the method described in WO2005/049546.
Compound M4 was synthesized according to the method described in WO2013/191088.
Compound M5 was synthesized according to the method described in JP-A-2010-189630.
Compound M6 was synthesized according to the method described in JP-A-2015-063482.
Compound M7 was synthesized according to the method described in WO2015/145871.
Compound M8 was synthesized according to the method described in JP-A-2011-174062.
Commercially available products were used for compound M9 and compound M10.
Compound M11 was synthesized according to the method described in WO2012/086671.
Compound M12 was synthesized according to the method described in WO2016/031639.

<Synthesis of polymer compound HTL-1>
Polymer compound HTL-1 was synthesized using compound M1, compound M2 and compound M3 according to the method described in WO 2015/145871. The Mn of the polymer compound HTL-1 was 2.3×10 ⁴ and the Mw was 1.2×10 ⁵ .
In the polymer compound HTL-1, the theoretical values obtained from the amounts of the raw materials charged are the structural units derived from the compound M1, the structural units derived from the compound M2, and the structural units derived from the compound M3. It is a copolymer made up of a molar ratio of 45:5:50.

<Synthesis of polymer compound HP1>
Polymer compound HP1 was synthesized using compound M5 and compound M4 according to the method described in International Publication No. 2013/191088.
The Mn of the polymer compound HP1 was 9.7×10 ⁴ and the Mw was 2.9×10 ⁵ .
According to the theoretical value obtained from the amount of the raw material charged, the polymer compound HP1 is a copolymer composed of structural units derived from the compound M5 and structural units derived from the compound M4 at a molar ratio of 50:50. It is a coalescence.

<Procurement of polymer compound HP2 (polymer compound PVK)>
A polymer compound HP2 manufactured by Luminescence Technology was used.

<Synthesis of polymer compound BP1>
(Step 1) After making the inside of the reaction vessel an inert gas atmosphere, the above compound M5 (0.3444 g), the above compound M4 (0.5762 g), the above compound B2 (0.0851 g), dichlorobis(tris- o-Methoxyphenylphosphine)palladium (0.27 mg) and toluene (30 mL) were added and heated to 80°C.
(Step 2) Thereafter, a 20% by mass tetraethylammonium hydroxide aqueous solution (16.0 g) was added dropwise thereto, and refluxed for 6 hours.
(Step 3) After that, phenylboronic acid (45.7 mg) and dichlorobis(tris-o-methoxyphenylphosphine)palladium (0.27 mg) were added thereto and stirred at 80° C. for 3 hours.
(Step 4) After cooling the reaction mixture, an aqueous sodium diethyldithiacarbamate solution was added, and the mixture was stirred at 40°C for 1 hour. After cooling the reaction solution and removing the aqueous layer, the resulting organic layer was washed twice with 3 mass % aqueous ammonia and twice with water. The resulting solution was added dropwise to methanol and stirred to cause precipitation. The precipitate was dissolved in toluene (44 mL), alumina (26 g) was added, and the mixture was stirred for 3 hours, and the resulting suspension was passed through a silica gel column for purification. The resulting solution was added dropwise to methanol and stirred to produce a precipitate. The resulting precipitate was collected by filtration and dried to obtain 0.51 g of polymer compound BP1. The polymer compound BP1 had an Mn of 6.2×10 ⁴ and an Mw of 1.5×10 ⁵ .
In the polymer compound BP1, the theoretical value obtained from the amount of the raw material charged is that the structural unit derived from the compound M5, the structural unit derived from the compound M4, and the structural unit derived from the compound B2 are 50: It is a copolymer made up of a 45:5 molar ratio.

<Synthesis of polymer compound BP2>
(Step 1) After making the inside of the reaction vessel an inert gas atmosphere, the above compound M5 (0.3070 g), the above compound M4 (0.6403 g), the above compound B3 (0.0927 g), dichlorobis(tris- o-Methoxyphenylphosphine)palladium (0.27 mg) and toluene (31 mL) were added and heated to 80°C.
(Step 2) Thereafter, a 20% by mass tetraethylammonium hydroxide aqueous solution (15.7 g) was added dropwise thereto, and refluxed for 6 hours.
(Step 3) After that, phenylboronic acid (45.7 mg) and dichlorobis(tris-o-methoxyphenylphosphine)palladium (0.27 mg) were added thereto and stirred at 80° C. for 3 hours.
(Step 4) After cooling the reaction mixture, an aqueous sodium diethyldithiacarbamate solution was added, and the mixture was stirred at 40°C for 1 hour. After cooling the reaction solution and removing the aqueous layer, the resulting organic layer was washed twice with 3 mass % aqueous ammonia and twice with water. The resulting solution was added dropwise to methanol and stirred to cause precipitation. After the precipitate was dissolved in toluene (44 mL), alumina (27 g) was added, and the mixture was stirred for 3 hours, the resulting suspension was passed through a silica gel column for purification. The resulting solution was added dropwise to methanol and stirred to produce a precipitate. The precipitate was collected by filtration and dried to obtain 0.52 g of polymer compound BP2.
The polymer compound BP2 had Mn of 6.3×10 ⁴ and Mw of 1.5×10 ⁵ .
In the polymer compound BP2, the theoretical value obtained from the amount of the charged raw material is 45: It is a copolymer made up of a 50:5 molar ratio.

(Synthesis of polymer compound BP3)
Polymer compound BP3 was synthesized using compound M10, compound M12, compound M11 and compound B2 according to the method described in WO2019/004248. The polymer compound BP3 had an Mn of 4.5×10 ⁴ and an Mw of 1.1×10 ⁵ .
According to the theoretical values obtained from the amounts of the raw materials, the polymer compound BP3 has a structural unit derived from the compound M10, a structural unit derived from the compound M12, a structural unit derived from the compound M11, and a structural unit derived from the compound B2. The derived structural units are copolymers made up in a molar ratio of 45:5:49:1.

(Synthesis of polymer compound MP1)
Polymer compound MP1 was synthesized using compound M5, compound M4, compound M7, and compound MC3 according to the method described in JP-A-2015-038195. The Mn of the polymer compound MP1 was 9.0×10 ⁴ and the Mw was 2.3×10 ⁵ .
According to the theoretical values obtained from the amounts of the raw materials, the polymer compound MP1 has a structural unit derived from the compound M5, a structural unit derived from the compound M4, a structural unit derived from the compound M7, and a structural unit derived from the compound MC3. The derived constitutional units are copolymers composed in a molar ratio of 50:15:20.5:14.5.

<Synthesis of polymer compound ET1>
(Synthesis of polymer compound ET1a)
The polymer compound ET1a is a compound ET1-1 synthesized according to the method described in JP-A-2012-33845, and a compound ET1-2 synthesized according to the method described in JP-A-2012-33845. It was synthesized according to the method described in JP-A-2012-33845.

Mn of the polymer compound ET1a was 5.2×10 ⁴ .

The polymer compound ET1a is composed of structural units derived from the compound ET1-1 and structural units derived from the compound ET1-2 at a molar ratio of 50:50, according to the theoretical value obtained from the amount of the raw materials. It is a copolymer that has been

(Synthesis of polymer compound ET1)
After making the inside of reaction container into inert gas atmosphere, high molecular compound ET1a (200 mg), tetrahydrofuran (20 mL), and ethanol (20 mL) were added, and it heated at 55 degreeC. After that, cesium hydroxide (200 mg) dissolved in water (2 mL) was added thereto, and the mixture was stirred at 55°C for 6 hours. Then, after cooling to room temperature, a solid was obtained by concentrating under reduced pressure. The resulting solid was washed with water and then dried under reduced pressure to obtain polymer compound ET1 (150 mg, pale yellow solid). From the NMR spectrum of the obtained polymer compound ET1, it was confirmed that the signal derived from the ethyl group at the ethyl ester site of the polymer compound ET1a completely disappeared.

<Synthesis of compound ET2>
Low molecular weight compound ET2 was synthesized according to the method described in WO2020/162156.

<Synthesis of polymer compound ET3>
(Synthesis of polymer compound ET3a)
Polymer compound ET3a is compound ET3-1 synthesized according to the method described in WO 2012/011418, and compound ET3-2 synthesized according to the method described in WO 2012/011418. Using, it was synthesized according to the method described in International Publication No. 2012/011418.

Mn of the polymer compound ET3a was 1.3×10 ⁴ .

The polymer compound ET3a is composed of structural units derived from the compound ET3-1 and structural units derived from the compound ET3-2 at a molar ratio of 50:50, according to the theoretical values obtained from the amounts of the raw materials. It is a copolymer that has been

(Synthesis of polymer compound ET3)
Polymer compound ET3 was obtained in the same manner as in (Synthesis of polymer compound ET1), except that "polymer compound ET3a" was used instead of "polymer compound ET1a" in (synthesis of polymer compound ET1). rice field. From the NMR spectrum of the polymer compound ET3 obtained, it was confirmed that the signal derived from the ethyl group in the ethyl ester portion of the polymer compound ET3a had completely disappeared.

<Synthesis of polymer compound ET4>
(Synthesis of polymer compound ET4a)
Polymer compound ET4a is synthesized according to the method described in WO 2015/159932 using compound M6 and compound ET3-2 synthesized according to the method described in WO 2012/011418. bottom.

Mn of the polymer compound ET4a was 1.1×10 ⁴ .

In the polymer compound ET4a, the theoretical value obtained from the amount of the charged raw material was composed of structural units derived from the compound M6 and structural units derived from the compound ET3-2 at a molar ratio of 50:50. It is a copolymer.

(Synthesis of polymer compound ET4)
Polymer compound ET4 was obtained in the same manner as in (Synthesis of polymer compound ET1) except that "polymer compound ET4a" was used instead of "polymer compound ET1a" in (synthesis of polymer compound ET1). rice field. From the NMR spectrum of the obtained polymer compound ET4, it was confirmed that the signal derived from the ethyl group of the ethyl ester site of the polymer compound ET4a completely disappeared.

<Synthesis of polymer compound ET5>
(Synthesis of polymer compound ET5a)
Polymer compound ET5a was synthesized according to the method described in WO 2015/159932 using compound M5 and compound ET1-2 synthesized according to the method described in JP-A-2012-33845.

Mn of the polymer compound ET5a was 3.2×10 ⁴ .

In the polymer compound ET5a, the theoretical value obtained from the amount of the charged raw material was composed of structural units derived from the compound M5 and structural units derived from the compound ET1-2 at a molar ratio of 50:50. It is a copolymer.

(Synthesis of polymer compound ET5)
Polymer compound ET5 was obtained in the same manner as in (Synthesis of polymer compound ET1) except that "polymer compound ET5a" was used instead of "polymer compound ET1a" in (synthesis of polymer compound ET1). rice field. From the NMR spectrum of the obtained polymer compound ET5, it was confirmed that the signal derived from the ethyl group at the ethyl ester site of the polymer compound ET5a completely disappeared.

<Synthesis of polymer compound ET6>
Polymer compound ET6 was synthesized using compound M8 and compound M9 according to the method described in International Publication No. 2012/086670.
The polymer compound ET6 had Mn of 1.3×10 ⁵ and Mw of 3.6×10 ⁵ .
The polymer compound ET6 is a copolymer composed of structural units derived from the compound M8 and structural units derived from the compound M9 at a molar ratio of 50:50, according to the theoretical values obtained from the amounts of the raw materials. It is a coalescence.

<Synthesis of polymer compound ET7>
Polymer compound ET7 was synthesized using compound M5, compound M4 and compound M7 according to the method described in WO 2015/008851.
The Mn of the polymer compound ET7 was 8.5×10 ⁴ and the Mw was 2.2×10 ⁵ .
In the polymer compound ET7, the theoretical value obtained from the amount of the charged raw material is 50: It is a copolymer made up of a 26:24 molar ratio.

<Synthesis of polymer compound ET8>
Polymer compound ET8 was synthesized using compound M5 and compound M3 according to the method described in WO2019/004247.
The Mn of the polymer compound ET8 was 4.5×10 ⁴ and the Mw was 1.5×10 ⁵ .
Polymer compound ET8 is a copolymer composed of a structural unit derived from compound M5 and a structural unit derived from compound M3 at a molar ratio of 50:50, according to the theoretical value obtained from the amount of raw materials. It is a coalescence.

<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. On the anode, ND-3202 (manufactured by Nissan Chemical Industries, Ltd.), which is a hole injection material, was formed into a film with a thickness of 35 nm by a spin coating method to form a coating film. The substrate on which the coating film was formed was heated on a hot plate at 50° C. for 3 minutes in an air atmosphere, and further heated at 230° C. for 15 minutes to form a hole injection layer.

(Formation of hole transport layer)
A polymer compound HTL-1 was 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. A pore transport layer was formed. By this heating, the polymer compound HTL-1 was in a crosslinked state.

(Formation of first layer)
Compound H1, compound MC1 and compound B1 (compound H1/compound MC1/compound B1=73 mass %/25 mass %/2 mass %) were dissolved in toluene at a concentration of 1.8 mass %. Using the obtained toluene solution, a film having a thickness of 60 nm was formed on the hole transport layer by spin coating, and the first layer ( light-emitting layer) was formed.

(Formation of second layer)
The polymer compound ET1 was dissolved in 2,2,3,3,4,4,5,5-octafluoro-1-pentanol at a concentration of 0.4% by mass. Using the obtained 2,2,3,3,4,4,5,5-octafluoro-1-pentanol solution, a film having a thickness of 20 nm was formed on the first layer by spin coating. A second layer (electron transport layer) was formed by heating at 130° C. for 10 minutes in a nitrogen gas atmosphere.

(Formation of cathode)
After reducing the pressure of the substrate on which the second 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 second layer as a cathode, and then sodium fluoride. About 80 nm of aluminum was evaporated on top of the layer. 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 driving voltage [V] and CIE chromaticity coordinates of the light-emitting element D1 at 100 cd/m ² were measured.

<Example D2> Production and Evaluation of Light-Emitting Device D2 Example D1 except that "low-molecular-weight compound ET2" was used instead of "high-molecular-weight compound ET1" in (formation of second layer) of Example D1. A light-emitting device D2 was fabricated in the same manner as above.
EL light emission was observed by applying a voltage to the light emitting element D2. The driving voltage [V] and CIE chromaticity coordinates of the light-emitting element D2 at 100 cd/m ² were measured.

<Example D3> Production and Evaluation of Light-Emitting Device D3 Example D1 except that "polymer compound ET3" was used instead of "polymer compound ET1" in (formation of the second layer) of Example D1. A light-emitting device D3 was fabricated in the same manner as above.
EL light emission was observed by applying a voltage to the light emitting element D3. The driving voltage [V] and CIE chromaticity coordinates of the light-emitting element D3 at 100 cd/m ² were measured.

<Example D4> Production and Evaluation of Light Emitting Device D4 Example D1 except that "polymer compound ET4" was used instead of "polymer compound ET1" in (formation of the second layer) of Example D1. A light-emitting device D4 was fabricated in the same manner as above.
EL light emission was observed by applying a voltage to the light emitting element D4. The driving voltage [V] and CIE chromaticity coordinates of the light-emitting element D4 at 100 cd/m ² were measured.

<Example D5> Production and Evaluation of Light-Emitting Element D5 Example D1 except that "polymer compound ET5" was used instead of "polymer compound ET1" in (formation of the second layer) of Example D1. A light-emitting device D5 was fabricated in the same manner as above.
EL light emission was observed by applying a voltage to the light emitting element D5. The driving voltage [V] and CIE chromaticity coordinates of the light-emitting element D5 at 100 cd/m ² were measured.

<Example D6> Production and evaluation of light-emitting element D6 “Compound H1, compound MC1 and compound B1 (compound H1/compound MC1/compound B1 = 73 mass%/25 mass%) in (Formation of first layer) of Example D1 %/2% by mass)” was changed to “Compound H1, polymer compound MP1 and compound B1 (compound H1/polymer compound MP1/compound B1 = 73% by mass/25% by mass/2% by mass)”. A light-emitting device D6 was produced in the same manner as in Example D1.
EL light emission was observed by applying a voltage to the light emitting element D6. The driving voltage [V] and CIE chromaticity coordinates of the light-emitting element D6 at 100 cd/m ² were measured.

<Example D7> Production and Evaluation of Light-Emitting Element D7 “Compound H1, Compound MC1 and Compound B1 (Compound H1/Compound MC1/Compound B1=73% by mass/25% by mass) in (Formation of first layer) of Example D1 %/2% by mass)” was changed to “Compound H1, polymer compound MP1 and polymer compound BP1 (compound H1/polymer compound MP1/polymer compound BP1=73% by mass/25% by mass/2% by mass)”. A light-emitting device D7 was fabricated in the same manner as in Example D1 except for the above.
EL light emission was observed by applying a voltage to the light emitting element D7. The driving voltage [V] and CIE chromaticity coordinates of the light-emitting element D7 at 100 cd/m ² were measured.

<Example D8> Production and evaluation of light-emitting element D8 “Compound H1, Compound MC1 and Compound B1 (Compound H1/Compound MC1/Compound B1 = 73% by mass/25% by mass” in (Formation of first layer) of Example D1 %/2% by mass)” was changed to “Compound H1, polymer compound MP1 and polymer compound BP2 (compound H1/polymer compound MP1/polymer compound BP2=73% by mass/25% by mass/2% by mass)”. A light-emitting device D8 was fabricated in the same manner as in Example D1 except for the above.
EL light emission was observed by applying a voltage to the light emitting element D8. The driving voltage [V] and CIE chromaticity coordinates of the light-emitting element D8 at 100 cd/m ² were measured.

<Example D9> Production and Evaluation of Light-Emitting Element D9 “Compound H1, Compound MC1 and Compound B1 (Compound H1/Compound MC1/Compound B1=73% by mass/25% by mass) in (Formation of first layer) of Example D1 %/2% by mass)” was changed to “Compound H1, polymer compound MP1 and polymer compound BP3 (compound H1/polymer compound MP1/polymer compound BP3=73% by mass/25% by mass/2% by mass)”. A light-emitting element D9 was fabricated in the same manner as in Example D1 except for the above.
EL light emission was observed by applying a voltage to the light emitting element D9. The driving voltage [V] and CIE chromaticity coordinates of the light-emitting element D9 at 100 cd/m ² were measured.

<Comparative Example CD1> Production and Evaluation of Light-Emitting Element CD1 A light-emitting element CD1 was produced in the same manner as in Example D1, except that (formation of the second layer) of Example D1 was not performed.
EL light emission was observed by applying a voltage to the light emitting element CD1. The driving voltage [V] and CIE chromaticity coordinates of the light-emitting element CD1 at 100 cd/m ² were measured.

Table 5 shows the results of Examples D1 to D9 and Comparative Example CD1. In Table 5, the driving voltage difference [V] indicates the difference between the driving voltage [V] of the light emitting element CD1 and the driving voltage [V] of the light emitting elements D1 to D9.

<Example D10> Production and evaluation of light emitting device D10 (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. On the anode, ND-3202 (manufactured by Nissan Chemical Industries, Ltd.), which is a hole injection material, was formed into a film with a thickness of 35 nm by a spin coating method to form a coating film. The substrate on which the coating film was formed was heated on a hot plate at 50° C. for 3 minutes in an air atmosphere, and further heated at 230° C. for 15 minutes to form a hole injection layer.

(Formation of hole transport layer)
A polymer compound HTL-1 was 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. A pore transport layer was formed. By this heating, the polymer compound HTL-1 was in a crosslinked state.

(Formation of first layer)
Compound H1, compound MC2 and polymer compound BP1 (compound H1/compound MC2/polymer compound BP1=73% by mass/25% by mass/2% by mass) were dissolved in toluene at a concentration of 1.8% by mass. Using the obtained toluene solution, a film having a thickness of 60 nm was formed on the hole transport layer by spin coating, and the first layer ( light-emitting layer) was formed.

(Formation of second layer)
The polymer compound ET1 was dissolved in 2,2,3,3,4,4,5,5-octafluoro-1-pentanol at a concentration of 0.4% by mass. Using the obtained 2,2,3,3,4,4,5,5-octafluoro-1-pentanol solution, a film having a thickness of 20 nm was formed on the first layer by spin coating. A second layer (electron transport layer) was formed by heating at 130° C. for 10 minutes in a nitrogen gas atmosphere.

(Formation of cathode)
After reducing the pressure of the substrate on which the second 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 second layer as a cathode, and then sodium fluoride. About 80 nm of aluminum was evaporated on top of the layer. After vapor deposition, the substrate on which the cathode was formed was sealed with a glass substrate to produce a light-emitting device D10.

(Evaluation of Light Emitting Element)
EL emission was observed by applying a voltage to the light emitting element D10. The driving voltage [V] and CIE chromaticity coordinates of the light-emitting element D10 at 500 cd/m ² were measured.

<Example D11> Production and evaluation of light emitting element D11 “Compound H1, compound MC2 and polymer compound BP1 (compound H1/compound MC2/polymer compound BP1 = 73 mass %/25% by mass/2% by mass)” was changed to “Compound H1, Compound MC2 and Polymer Compound BP2 (Compound H1/Compound MC1/Polymer Compound BP2=73% by mass/25% by mass/2% by mass)”. A light-emitting device D11 was fabricated in the same manner as in Example D10 except for the above.

(Evaluation of Light Emitting Element)
EL light emission was observed by applying a voltage to the light emitting element D11. The driving voltage [V] and CIE chromaticity coordinates of the light-emitting element D11 at 500 cd/m ² were measured.

<Example D12> Production and evaluation of light-emitting element D12 “Compound H1, compound MC2 and polymer compound BP1 (compound H1/compound MC2/polymer compound BP1 = 73 mass %/25% by mass/2% by mass)” was changed to “Compound H1, Compound MC2 and Polymer Compound BP3 (Compound H1/Compound MC2/Polymer Compound BP3=73% by mass/25% by mass/2% by mass)”. A light-emitting device D12 was fabricated in the same manner as in Example D10, except for the above.

(Evaluation of Light Emitting Element)
EL light emission was observed by applying a voltage to the light emitting element D12. The driving voltage [V] and CIE chromaticity coordinates of the light-emitting element D12 at 500 cd/m ² were measured.

<Example D13> Production and evaluation of light-emitting element D13 "Compound H1, compound MC2 and polymer compound BP1 (compound H1/compound MC2/polymer compound BP1 = 73 mass %/25% by mass/2% by mass)” was changed to “Compound H1, Compound MC2 and Compound B1 (Compound H1/Compound MC2/Compound B1 = 73% by mass/25% by mass/2% by mass)”. A light-emitting device D13 was produced in the same manner as in Example D10.

(Evaluation of Light Emitting Element)
EL light emission was observed by applying a voltage to the light emitting element D13. The driving voltage [V] and CIE chromaticity coordinates of the light-emitting element D13 at 500 cd/m ² were measured.

<Example D14> Production and evaluation of light-emitting element D14 “Compound H1, compound MC2 and polymer compound BP1 (compound H1/compound MC2/polymer compound BP1 = 73 mass %/25% by mass/2% by mass)” was changed to “Compound H2, Compound MC2 and Compound B1 (Compound H2/Compound MC2/Compound B1 = 73% by mass/25% by mass/2% by mass)”. A light-emitting device D14 was produced in the same manner as in Example D10.

(Evaluation of Light Emitting Element)
EL emission was observed by applying a voltage to the light emitting element D14. The driving voltage [V] and CIE chromaticity coordinates of the light-emitting element D14 at 500 cd/m ² were measured.

<Example D15> Production and evaluation of light-emitting element D15 “Compound H1, compound MC2 and polymer compound BP1 (compound H1/compound MC2/polymer compound BP1 = 73 mass %/25% by mass/2% by mass)” was changed to “Compound H3, Compound MC2 and Compound B1 (Compound H3/Compound MC2/Compound B1 = 73% by mass/25% by mass/2% by mass)”. A light-emitting device D15 was produced in the same manner as in Example D10.

(Evaluation of Light Emitting Element)
EL light emission was observed by applying a voltage to the light emitting element D15. The driving voltage [V] and CIE chromaticity coordinates of the light-emitting element D15 at 500 cd/m ² were measured.

<Example D16> Production and evaluation of light-emitting element D16 Light emission was performed in the same manner as in Example D10, except that (formation of the first layer) of Example D10 was changed to the following (formation of the first layer-D16). A device D16 was produced.
(Formation of first layer D-16)
Compound HP1, compound MC2 and compound B1 (compound HP1/compound MC2/compound B1=73 mass %/25 mass %/2 mass %) were dissolved in toluene at a concentration of 1.0 mass %. Using the obtained toluene solution, a film having a thickness of 60 nm was formed on the hole transport layer by spin coating, and the first layer ( light-emitting layer) was formed.

(Evaluation of Light Emitting Element)
EL emission was observed by applying a voltage to the light emitting element D16. The driving voltage [V] and CIE chromaticity coordinates of the light-emitting element D16 at 500 cd/m ² were measured.

<Example D17> Production and Evaluation of Light-Emitting Element D17 (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. On the anode, ND-3202 (manufactured by Nissan Chemical Industries, Ltd.), which is a hole injection material, was formed into a film with a thickness of 35 nm by a spin coating method to form a coating film. The substrate on which the coating film was formed was heated on a hot plate at 50° C. for 3 minutes in an air atmosphere, and further heated at 230° C. for 15 minutes to form a hole injection layer.

(Formation of hole transport layer)
A polymer compound HTL-1 was 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. A pore transport layer was formed. By this heating, the polymer compound HTL-1 was in a crosslinked state.

(Formation of first layer)
Polymer compound HP2, compound MC2 and compound B1 (polymer compound HP2/compound MC2/compound B1=73% by mass/25% by mass/2% by mass) were dissolved in chlorobenzene at a concentration of 1.6% by mass. Using the obtained chlorobenzene solution, a film having a thickness of 60 nm was formed on the hole transport layer by a spin coating method, and the first layer ( light-emitting layer) was formed.

(Formation of second layer)
The polymer compound ET1 was dissolved in 2,2,3,3,4,4,5,5-octafluoro-1-pentanol at a concentration of 0.4% by mass. Using the obtained 2,2,3,3,4,4,5,5-octafluoro-1-pentanol solution, a film having a thickness of 20 nm was formed on the first layer by spin coating. A second layer (electron transport layer) was formed by heating at 130° C. for 10 minutes in a nitrogen gas atmosphere.

(Formation of cathode)
After reducing the pressure of the substrate on which the second 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 second layer as a cathode, and then sodium fluoride. About 80 nm of aluminum was evaporated on top of the layer. After vapor deposition, the substrate on which the cathode was formed was sealed with a glass substrate to produce a light-emitting element D17.

(Evaluation of Light Emitting Element)
EL light emission was observed by applying a voltage to the light emitting element D17. The driving voltage [V] and CIE chromaticity coordinates of the light-emitting element D17 at 500 cd/m ² were measured.

<Example D18> Production and evaluation of light-emitting element D18 Light emission was performed in the same manner as in Example D17, except that "polymer compound ET1" in Example D17 (formation of second layer) was changed to "compound ET2". A device D18 was produced.

(Evaluation of Light Emitting Element)
EL emission was observed by applying a voltage to the light emitting element D18. The driving voltage [V] and CIE chromaticity coordinates of the light-emitting element D18 at 500 cd/m ² were measured.

<Example D19> Production and evaluation of light-emitting element D19 In the same manner as in Example D17, except that "polymer compound ET1" in Example D17 (formation of the second layer) was changed to "polymer compound ET3". , a light-emitting device D19 was produced.

(Evaluation of Light Emitting Element)
EL light emission was observed by applying a voltage to the light emitting element D19. The driving voltage [V] and CIE chromaticity coordinates of the light-emitting element D19 at 500 cd/m ² were measured.

<Example D20> Production and evaluation of light-emitting element D20 In the same manner as in Example D17, except that "polymer compound ET1" in Example D17 (formation of second layer) was changed to "polymer compound ET4". , a light-emitting device D20 was fabricated.

(Evaluation of Light Emitting Element)
EL emission was observed by applying a voltage to the light emitting element D20. The driving voltage [V] and CIE chromaticity coordinates of the light-emitting element D20 at 500 cd/m ² were measured.

<Example D21> Production and evaluation of light-emitting element D21 In the same manner as in Example D17, except that "polymer compound ET1" in Example D17 (formation of the second layer) was changed to "polymer compound ET5". , a light-emitting device D21 was produced.

(Evaluation of Light Emitting Element)
EL light emission was observed by applying a voltage to the light emitting element D21. The driving voltage [V] and CIE chromaticity coordinates of the light-emitting element D21 at 500 cd/m ² were measured.

<Example D22> Production and evaluation of light-emitting element D22 Light emission was performed in the same manner as in Example D17, except that (formation of the second layer) of Example D17 was changed to the following (formation of the second layer-D22). A device D22 was produced.
(Formation of second layer D-22)
A polymer compound ET6 was dissolved in toluene at a concentration of 0.6% by mass. Using the obtained toluene solution, a film with a thickness of 20 nm was formed on the first layer by a spin coating method, and the second layer (electron transport layer) was formed.

(Evaluation of Light Emitting Element)
EL light emission was observed by applying a voltage to the light emitting element D22. The driving voltage [V] and CIE chromaticity coordinates of the light-emitting element D22 at 500 cd/m ² were measured.

<Example D23> Production and evaluation of light-emitting element D23 Light emission was performed in the same manner as in Example D17, except that (formation of the second layer) of Example D17 was changed to the following (formation of the second layer-D23). A device D23 was produced.
(Formation of second layer D-23)
Polymer compound ET7 was dissolved in toluene at a concentration of 0.6% by mass. Using the obtained toluene solution, a film with a thickness of 20 nm was formed on the first layer by a spin coating method, and the second layer (electron transport layer) was formed.

(Evaluation of Light Emitting Element)
EL light emission was observed by applying a voltage to the light emitting element D23. The driving voltage [V] and CIE chromaticity coordinates of the light-emitting element D23 at 500 cd/m ² were measured.

<Example D24> Production and evaluation of light-emitting element D24 Light emission was performed in the same manner as in Example D17, except that (formation of the second layer) of Example D17 was changed to the following (formation of the second layer-D24). A device D24 was produced.
(Formation of second layer D-24)
Polymer compound ET8 was dissolved in toluene at a concentration of 0.6% by mass. Using the obtained toluene solution, a film with a thickness of 20 nm was formed on the first layer by a spin coating method, and the second layer (electron transport layer) was formed.

(Evaluation of Light Emitting Element)
EL light emission was observed by applying a voltage to the light emitting element D24. The driving voltage [V] and CIE chromaticity coordinates of the light-emitting element D24 at 500 cd/m ² were measured.

<Example D25> Production and evaluation of light emitting device D25 (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. On the anode, ND-3202 (manufactured by Nissan Chemical Industries, Ltd.), which is a hole injection material, was formed into a film with a thickness of 35 nm by a spin coating method to form a coating film. The substrate on which the coating film was formed was heated on a hot plate at 50° C. for 3 minutes in an air atmosphere, and further heated at 230° C. for 15 minutes to form a hole injection layer.

(Formation of hole transport layer)
A polymer compound HTL-1 was 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. A pore transport layer was formed. By this heating, the polymer compound HTL-1 was in a crosslinked state.

(Formation of first layer)
Polymer compound HP2 and compound B1 (polymer compound HP2/compound B1=98% by mass/2% by mass) were dissolved in chlorobenzene at a concentration of 1.3% by mass. Using the obtained chlorobenzene solution, a film having a thickness of 60 nm was formed on the hole transport layer by a spin coating method, and the first layer ( light-emitting layer) was formed.

(Formation of second layer)
The polymer compound ET1 was dissolved in 2,2,3,3,4,4,5,5-octafluoro-1-pentanol at a concentration of 0.4% by mass. Using the obtained 2,2,3,3,4,4,5,5-octafluoro-1-pentanol solution, a film having a thickness of 20 nm was formed on the first layer by spin coating. A second layer (electron transport layer) was formed by heating at 130° C. for 10 minutes in a nitrogen gas atmosphere.

(Formation of cathode)
After reducing the pressure of the substrate on which the second 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 second layer as a cathode, and then sodium fluoride. About 80 nm of aluminum was evaporated on top of the layer. After vapor deposition, the substrate on which the cathode was formed was sealed with a glass substrate to produce a light-emitting device D25.

(Evaluation of Light Emitting Element)
EL light emission was observed by applying a voltage to the light emitting element D25. The driving voltage [V] and CIE chromaticity coordinates of the light-emitting element D25 at 500 cd/m ² were measured.

<Example D26> Production and evaluation of light-emitting device D26 In the same manner as in Example D25, except that "polymer compound ET1" in Example D25 (formation of the second layer) was changed to "polymer compound ET2". , a light-emitting device D26 was produced.

(Evaluation of Light Emitting Element)
EL light emission was observed by applying a voltage to the light emitting element D26. The driving voltage [V] and CIE chromaticity coordinates of the light-emitting element D26 at 500 cd/m ² were measured.

<Example D27> Production and evaluation of light-emitting device D27 In the same manner as in Example D25, except that "polymer compound ET1" in Example D25 (formation of the second layer) was changed to "polymer compound ET4". , a light-emitting device D27 was produced.

(Evaluation of Light Emitting Element)
EL light emission was observed by applying a voltage to the light emitting element D27. The driving voltage [V] and CIE chromaticity coordinates of the light-emitting element D27 at 500 cd/m ² were measured.

<Example D28> Production and evaluation of light-emitting device D28 In the same manner as in Example D25, except that "polymer compound ET1" in Example D25 (formation of second layer) was changed to "polymer compound ET5". , a light-emitting device D28 was produced.

(Evaluation of Light Emitting Element)
EL light emission was observed by applying a voltage to the light emitting element D28. The driving voltage [V] and CIE chromaticity coordinates of the light-emitting element D28 at 500 cd/m ² were measured.

<Example D29> Production and evaluation of light-emitting element D29 Light emission was performed in the same manner as in Example D25, except that (formation of the second layer) of Example D25 was changed to (formation of the second layer-D22). A device D29 was produced.

(Evaluation of Light Emitting Element)
EL light emission was observed by applying a voltage to the light emitting element D29. The driving voltage [V] and CIE chromaticity coordinates of the light-emitting element D29 at 500 cd/m ² were measured.

<Comparative Example CD2> Production and Evaluation of Light-Emitting Element CD2 A light-emitting element CD2 was produced in the same manner as in Example D17, except that (formation of the second layer) of Example D17 was not performed.

(Evaluation of Light Emitting Element)
EL light emission was observed by applying a voltage to the light emitting element CD2. The driving voltage [V] and CIE chromaticity coordinates of the light-emitting element CD2 at 500 cd/m ² were measured.

<Comparative Example CD3> Fabrication and Evaluation of Light-Emitting Element CD3 A light-emitting element CD3 was fabricated in the same manner as in Example D25, except that (formation of the second layer) of Example D25 was not performed.

(Evaluation of Light Emitting Element)
EL light emission was observed by applying a voltage to the light emitting element CD3. The driving voltage [V] and CIE chromaticity coordinates of the light-emitting element CD3 at 500 cd/m ² were measured.

Table 6 shows the results of Examples D11 to D29 and Comparative Examples CD2 to CD3. In Table 6, the driving voltage difference [V] indicates the difference between the driving voltage [V] of the light emitting element CD3 and the driving voltage [V] of the light emitting elements D11 to D29 and the light emitting element CD2.

As is clear from Tables 5 and 6, the anode, the cathode, the first layer provided between the anode and the cathode, and the second layer provided between the first layer and the cathode , the driving voltage is lower than that of the light emitting element of the comparative example which does not have the second layer.

Claims (14)

A light-emitting device comprising an anode, a cathode, a first layer provided between the anode and the cathode, and a second layer provided between the first layer and the cathode, ,
wherein the first layer comprises a condensed heterocyclic skeleton (b) containing a boron atom and at least one selected from the group consisting of an oxygen atom, a sulfur atom, a selenium atom, an ^sp3 carbon atom and a nitrogen atom in the ring; and at least one selected from the group consisting of a low-molecular-weight compound (B) having a is a layer containing
The second layer includes a low-molecular-weight compound represented by the formula (ET-1), a low-molecular-weight compound represented by the formula (ET-2), and a low-molecular-weight compound represented by the formula (ET-1). A structural unit having a group obtained by removing one or more hydrogen atoms from a compound, a structural unit having a group obtained by removing one or more hydrogen atoms from a low-molecular-weight compound represented by formula (ET-2), represented by formula (X) and a layer containing at least one selected from the group consisting of polymer compounds containing at least one structural unit selected from the group consisting of structural units represented by formula (Y) A light-emitting element.

[In the formula,
nE1 represents an integer of 1 or more.
Ar ^E1 represents an aromatic hydrocarbon group or a heterocyclic group, and these groups may have a substituent.
R ^E1 represents a group represented by formula (ES-1). When multiple R ^E1 are present, they may be the same or different. ]
-R ^E3 - {(Q ^E1 ) _nE3 - Y ^E1 (M ^E1 ) _aE1 (Z ^E1 ) _bE1 } _mE1 (ES-1)
[In the formula,
nE3 and bE1 each independently represent an integer of 0 or greater, and aE1 and mE1 each independently represent an integer of 1 or greater. When multiple nE3, aE1 and bE1 are present, they may be the same or different. However, mE1 is 1 when R ^E3 is a single bond. aE1 and bE1 are selected so that the charge of the group represented by formula (ES-1) is zero.
R ^E3 represents a single bond, a hydrocarbon group, a heterocyclic group or O—R ^E3 ' (R ^E3 ' represents a hydrocarbon group or a heterocyclic group), and these groups have a substituent; may
Q ^E1 represents an alkylene group, a cycloalkylene group, an arylene group, an oxygen atom or a sulfur atom, and these groups may have a substituent. When multiple Q ^E1 are present, they may be the same or different.
Y ^E1 represents -CO ₂ ^- , -SO ₃ ^- , -SO ₂ ^- or -PO ₃ ^2- . When multiple Y ^E1 are present, they may be the same or different.
M ^E1 represents an alkali metal cation, an alkaline earth metal cation or an ammonium cation, and the ammonium cation may have a substituent. When multiple M ^E1 are present, they may be the same or different.
Z ^E1 is F ⁻ , Cl ⁻ , Br ⁻ , I ⁻ , OH ⁻ , B(R ^E4 ) ₄ ⁻ , R ^E4 SO ₃ ⁻ , R ^E4 COO ⁻ , NO ₃ ⁻ , SO ₄ ²⁻ , HSO ₄ ⁻ , PO ₄ ^3- , HPO ₄ ^2- , H ₂ PO ₄ ^- , BF ₄ ^- or PF ₆ ^- . R ^E4 represents an alkyl group, a cycloalkyl group or an aryl group, and these groups may have a substituent. When multiple Z ^E1 are present, they may be the same or different. ]

[In the formula,
nE2 represents an integer of 1 or more.
Ar ^E2 represents an aromatic hydrocarbon group or a heterocyclic group, and these groups may have a substituent.
R ^E2 represents a group represented by formula (ES-2). When multiple R ^E2 are present, they may be the same or different. ]
-R ^E5 - {(Q ^E2 ) _nE4 - Y ^E2 (M ^E2 ) _aE2 (Z ^E2 ) _bE2 } _mE2 (ES-2)
[In the formula,
nE4 and bE2 each independently represent an integer of 0 or greater, and aE2 and mE2 each independently represent an integer of 1 or greater. When multiple nE4, aE2 and bE2 are present, they may be the same or different. However, mE2 is 1 when R ^E5 is a single bond. aE2 and bE2 are selected so that the charge of the group represented by formula (ES-2) is zero.
R ^E5 represents a single bond, a hydrocarbon group, a heterocyclic group or O—R ^E5 ' (R ^E5 ' represents a hydrocarbon group or a heterocyclic group), and these groups have a substituent; may
Q ^E2 represents an alkylene group, a cycloalkylene group, an arylene group, an oxygen atom or a sulfur atom, and these groups may have a substituent. When multiple Q ^E2 are present, they may be the same or different.
Y ^E2 represents -C ⁺ R ^E6 ₂ , -N ⁺ R ^E6 ₃ , -P ⁺ R ^E6 ₃ , -S ⁺ R ^E6 ₂ or -I ⁺ R ^E6 ₂ . R ^E6 represents a hydrogen atom, an alkyl group, a cycloalkyl group or an aryl group, and these groups may have a substituent. A plurality of R ^E6 may be the same or different. When multiple Y ^E2 are present, they may be the same or different.
M ^E2 is F ⁻ , Cl ⁻ , Br ⁻ , I ⁻ , OH ⁻ , B(R ^E7 ) ₄ ⁻ , R ^E7 SO ₃ ⁻ , R ^E7 COO ⁻ , BF ₄ ⁻ , SbCl ₆ ⁻ or SbF ₆ ⁻ ; show. R ^E7 represents an alkyl group, a cycloalkyl group or an aryl group, and these groups may have a substituent.
When multiple M ^E2 are present, they may be the same or different.
Z ^E2 represents an alkali metal cation or an alkaline earth metal cation. When multiple Z ^E2 are present, they may be the same or different. ]

[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. ] The second layer comprises a structural unit having a group obtained by removing one or more hydrogen atoms from the low-molecular-weight compound represented by the formula (ET-1) and the low-molecular-weight compound represented by the formula (ET-2). 2. The light-emitting device according to claim 1, which is a layer containing a polymer compound containing at least one structural unit selected from the group consisting of structural units having a group obtained by removing one or more hydrogen atoms from . The luminescence according to claim 1 or 2, wherein the condensed heterocyclic skeleton (b) contains a boron atom and at least one selected from the group consisting of an oxygen atom, a sulfur atom and a nitrogen atom in the ring. element. 4. The light-emitting device according to claim 3, wherein the condensed heterocyclic skeleton (b) contains a boron atom and a nitrogen atom in the ring. Claim 1, wherein the low-molecular-weight 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). Or the light-emitting device according to claim 2.

[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 an oxygen atom, a sulfur atom, a selenium atom, a group represented by -N(Ry)-, an alkylene group or a cycloalkylene 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 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. ] 6. The light-emitting device according to claim 5, wherein said Y ¹ , said Y ² and said Y ³ are an oxygen atom, a sulfur atom or a group represented by -N(Ry)-. 7. The light-emitting device according to claim 6, wherein said Y ¹ , said Y ² and said Y ³ are groups represented by -N(Ry)-. The polymer compound (A 3. The light-emitting device according to claim 1, further comprising at least one selected from the group consisting of:

[In the formula,
M represents a rhodium atom, a palladium atom, an iridium atom or a platinum atom.
ⁿ¹ represents an integer of 1 or more, and ⁿ² represents an integer of 0 or more. However, n ¹ +n ² is 3 when M is a rhodium atom or an iridium atom, and n ¹ +n ² is 2 when M is a palladium atom or a platinum atom.
E ¹ and E ² each independently represent a carbon atom or a nitrogen atom. When multiple E ¹ and E ² are present, they may be the same or different.
Ring L ¹ represents an aromatic heterocycle, and the ring 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 rings L ¹ are present, they may be the same or different.
Ring ^L2 represents an aromatic hydrocarbon ring or an aromatic heterocyclic ring, and these rings 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 there is more than one ring ^L2 , they may be the same or different.
The substituent that ring L ¹ may have and the substituent that ring L ² may have 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 be formed.
A ¹ -G ¹ -A ² represents an anionic bidentate ligand. A ¹ and A ² each independently represent a carbon atom, an oxygen atom or a nitrogen atom, and these atoms may be atoms constituting a ring. G ¹ represents a single bond or an atomic group forming a bidentate ligand together with A ¹ and A ² . When multiple A ¹ -G ¹ -A ² are present, they may be the same or different. ] The ring L ¹ is an aromatic heterocyclic ring containing a 5-membered ring or an aromatic heterocyclic ring containing a 6-membered ring, these rings may have a substituent, and ring L ² is a 5-membered heterocyclic ring. An aromatic hydrocarbon ring containing a membered ring or a 6-membered ring, or an aromatic heterocyclic ring containing a 5-membered ring or a 6-membered ring, and these rings may have a substituent, according to claim 8 The described light-emitting device. The ring L ¹ is a pyridine ring, a diazabenzene ring, an azanaphthalene ring, a diazanaphthalene ring, a diazole ring or a triazole ring, these rings may have a substituent, and the ring L ² is , a benzene ring, a pyridine ring, or a diazabenzene ring, and these rings may have a substituent. The ring L ¹ is a diazole ring or a triazole ring, which may have a substituent, and the ring L ² is a benzene ring, which has a substituent 11. The light-emitting device according to claim 10, which may be The first layer is at least selected from the group consisting of a compound represented by formula (H-1), and a structural unit represented by formula (X) and a structural unit represented by formula (Y) 3. The light-emitting device according to claim 1, further comprising at least one selected from the group consisting of polymer compounds containing one structural unit.

[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 the 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. 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. ]

[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. ] 1 or claim 1, wherein 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. Item 3. The light-emitting device according to item 2. 3. The light-emitting device according to claim 1, wherein said first layer and said second layer are adjacent to each other.