JP2023050140A - Light-emitting element - Google Patents

Abstract

To provide a light-emitting element with excellent luminance life.SOLUTION: A light-emitting element includes an anode, a cathode, and a first layer and a second layer provided between the anode and the cathode. The first layer is a layer containing at least one kind selected from a group consisting of a metal complex expressed by a formula (1) and a polymer compound (A) including a constituent unit with a group excluding one or more hydrogen atoms from the metal complex expressed by the formula (1), and 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 including a cross-linked body of a compound with a cross-linking group.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, Non-Patent Document 1 describes a light-emitting element having a light-emitting layer containing metal complex A0 and compound B0. Note that this light-emitting element does not have a layer containing a crosslinked product of a compound having a crosslinkable group.

Journal of Materials Chemistry C, 2019, 7, 8562-8568

However, the above light-emitting element does not necessarily have a sufficient luminance lifetime.
Accordingly, an object of an embodiment of the present disclosure is to provide a light-emitting element with excellent luminance lifetime.

The present invention provides the following [1] to [17].

[1] A light emitting device having an anode, a cathode, and a first layer and a second layer provided between the anode and the cathode,
The first layer is
selected from the group consisting of a metal complex represented by the formula (1) and a polymer compound (A) containing a structural unit having a group obtained by removing one or more hydrogen atoms from the metal complex represented by the above formula (1) and at least one
A low-molecular-weight compound (B) having 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 polymer 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 containing
The light-emitting device, wherein the second layer is a layer containing a crosslinked compound having a crosslinkable group.

[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 heterocyclic ring containing a 5-membered ring, 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. ]
[2] The 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, and these rings have substituents. The light-emitting device according to [1] above, which may have a
[3] The ring L ¹ is a diazole ring or triazole ring, these rings may have a substituent, and the ring L ² is a benzene ring, a pyridine ring or a diazabenzene ring, The light-emitting device according to [1] or [2] above, wherein these rings may have a substituent.
[4] The above [1] to [3], 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. The light emitting device according to any one of 1.
[5] The light-emitting device according to [4] above, wherein the condensed heterocyclic skeleton (b) contains a boron atom and a nitrogen atom in the ring.
[6] 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). The light-emitting device according to any one of [1] to [3] above.

[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. ]
[7] The light-emitting device according to [6], wherein Y ¹ , Y ² and Y ³ are an oxygen atom, a sulfur atom or a group represented by -N(Ry)-.
[8] The light-emitting device according to [6] or [7] above, wherein Y ¹ , Y ² and Y ³ are groups represented by -N(Ry)-.
[9] The light-emitting device according to any one of [1] to [8] above, wherein the compound having the crosslinkable group is a polymer compound containing a structural unit having the crosslinkable group.
[10] The light-emitting device according to [9] above, wherein the structural unit having the cross-linking group is a structural unit represented by formula (Z) or a structural unit represented by formula (Z').

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

[In the formula,
mA, m and c each independently represent an integer of 0 or more. When multiple mA are present, they may be the same or different. When there are multiple m's, they may be the same or different.
Ar ⁵ represents a hydrocarbon group, a heterocyclic group, or a group in which at least one hydrocarbon group and at least one heterocyclic group are directly bonded, and these groups may have a substituent good. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. When multiple Ar ⁵ are present, they may be the same or different.
Ar ⁴ and Ar ⁶ each independently represent an arylene group or a divalent heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded.
K ^A represents an alkylene group, a cycloalkylene group, an arylene group, a divalent heterocyclic group, a group represented by -N(R'')-, an oxygen atom or a sulfur atom, and these groups are substituents. may have. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. R'' represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. When multiple K ^A are present, they may be the same or different.
X' represents a hydrogen atom, a bridging group, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. When multiple X' are present, they may be the same or different. However, at least one X' is a bridging group. ]
[11] The polymer compound containing a structural unit having a crosslinkable group contains at least one structural unit selected from the group consisting of structural units represented by formula (X) and structural units represented by formula (Y). The light-emitting device according to the above [9] or [10], further comprising

[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. ]
[12] The light-emitting device according to any one of [1] to [8] above, wherein the compound having a cross-linking group is a compound represented by formula (Z'').

[In the formula,
m ^B1 , m ^B2 and m ^B3 each independently represent an integer of 0 or more. A plurality of m ^B1 may be the same or different. When multiple ^mB3 are present, they may be the same or different.
Ar ⁷ represents a hydrocarbon group, a heterocyclic group, or a group in which at least one hydrocarbon group and at least one heterocyclic group are directly bonded, and these groups may have a substituent good. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. When multiple Ar ⁷ are present, they may be the same or different.
L ^B1 represents an alkylene group, a cycloalkylene group, an arylene group, a divalent heterocyclic group, a group represented by -N(R''')-, an oxygen atom or a sulfur atom, and these groups are substituents may have When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. R''' represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. When multiple L ^B1 are present, they may be the same or different. X'' represents a bridging group, a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. Multiple X'' may be the same or different. However, at least one of the plurality of X'' is a cross-linking group. ]
[13] The light-emitting device according to any one of [1] to [12] above, wherein the cross-linking group is at least one cross-linking group selected from Group A of cross-linking groups.
(Crosslinking group A group)

[In the formula, R ^XL represents a methylene group, an oxygen atom or a sulfur atom, and n ^XL represents an integer of 0 to 5. When multiple R ^XL are present, they may be the same or different. When multiple ^nXL are present, they may be the same or different. *1 represents the binding position. These bridging groups may have substituents, and when there are multiple substituents, they may be the same or different, and are bonded to each other to form a ring together with the atoms to which they are bonded. may ]
[14] 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 the above [1] to [13], further containing at least one selected from the group consisting of polymer compounds containing at least one constitutional 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. ]
[15] The above [ 1] The light-emitting device according to any one of [14].
[16] The light emitting device according to any one of [1] to [15] above, wherein the first layer and the second layer are adjacent to each other.
[17] The light emitting device according to any one of [1] to [16] above, wherein the second layer is a layer provided between the anode and the first layer.

According to an embodiment of the present disclosure, it is possible to provide a light emitting device with excellent luminance lifetime.

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 generally 6-60, preferably 6-40, more preferably 6-20, not including the number of carbon atoms in the substituents.
The aryloxy group may have a substituent. Examples of the aryloxy group include phenoxy group, naphthyloxy group, anthracenyloxy group, pyrenyloxy group, and groups in which some or all of the hydrogen atoms in these groups have been substituted with substituents.

A “heterocyclic group” means a group obtained by removing one or more hydrogen atoms directly bonded to atoms (carbon atoms or heteroatoms) constituting a ring from a heterocyclic compound. Among the heterocyclic groups, an "aromatic heterocyclic group", which is a group obtained by removing one or more hydrogen atoms directly bonded to atoms constituting a ring from an aromatic heterocyclic compound, is 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 have been further substituted with substituents.
Substituted amino groups include, for example, dimethylamino group, diethylamino group, diphenylamino group, bis(methylphenyl)amino group, bis(3,5-di-tert-butylphenyl)amino group, and hydrogen in these groups. Groups in which some or all of the atoms are further substituted with substituents are included.

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

A “crosslinking group” is a group capable of forming a new bond by subjecting it to heating, ultraviolet irradiation, near-ultraviolet irradiation, visible light irradiation, infrared irradiation, radical reaction, or the like. The cross-linking group is preferably at least one cross-linking group selected from Group A of cross-linking groups (that is, at least one group selected from groups represented by formulas (XL-1) to (XL-19)). .

The "substituent" includes, for example, a halogen atom, a cyano group, an alkyl group, a cycloalkyl group, an aryl group, a monovalent heterocyclic group, an alkoxy group, a cycloalkoxy group, an aryloxy group, an amino group, a substituted amino group, Alkenyl groups, cycloalkenyl groups, alkynyl groups and cycloalkynyl groups are included. A substituent may be a bridging group. In addition, when multiple substituents are present, they may be the same or different. In addition, when there are multiple substituents, they may bond with each other to form a ring together with the atoms to which they are bonded, but preferably do not form a ring.

The "divalent group" includes, for example, an alkylene group, a cycloalkylene group, an arylene group, a divalent heterocyclic group, a group represented by -N(R ⁰ )-, represented by -B(R ⁰ )- group represented by -P(R ⁰ )-, group represented by -(O=)P(R ⁰ )-, group represented by -O-, -S
A group represented by -, a group represented by -Se-, a group represented by -S(=O)-, a group represented by -S(=O) ₂ - and -C(=O)- The group represented by is 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 structurally optimized structure, _ΔEST of the compound is calculated by B3LYP-level time-dependent density functional theory. However, when 6-31G* contains an atom that cannot be used, LANL2DZ is used for that atom. Gaussian09 is used as a quantum chemical calculation program.

<Light emitting element>
A light-emitting device of the present disclosure is a light-emitting device having an anode, a cathode, and first and second layers provided between the anode and the cathode.

<First Layer>
In the light-emitting device of the present disclosure, the first layer comprises at least one compound selected from the group consisting of the metal complex represented by Formula (1) and the polymer compound (A) (hereinafter referred to as "compound (A) ”) and at least one compound selected from the group consisting of low-molecular-weight compounds (B) and high-molecular-weight compounds (B) (hereinafter also referred to as “compound (B)”). layer. That is, the first layer is a layer containing compound (A) and compound (B).
The first layer may contain only one type of compound (A), or may contain two or more types. The first layer may contain only one type of compound (B), or may contain two or more types.

The total content of the compound (B) and the compound (A) in the first layer may be within a range in which the function as the first layer is exhibited. The total content of the compound (B) and the compound (A) 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 light-emitting device of the present disclosure 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 preferably 5 to 50% by mass. % by mass, particularly preferably 10 to 30% by mass.
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 is, for example, 0.01 to 99 parts by mass when the total content of the compound (B) and the compound (A) is 100 parts by mass. Since the disclosed light-emitting device has an excellent luminance lifetime, the amount 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. It is particularly preferably 1 to 30 parts by mass, particularly preferably 2 to 20 parts by mass.

In the first layer, 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 caused to emit light more efficiently, and the luminance lifetime of the light-emitting element of the present disclosure is more excellent.

From the above point of view, in the first layer, the light-emitting device of the present disclosure has a more excellent luminance lifetime, so the compound (A) has at least It preferably has one function.
From the above point of view, if the light-emitting material is used as an example in the first layer, the luminance life of the light-emitting element of the present disclosure is superior, so the compound (B) preferably has light-emitting properties.
From the above point of view, in the first layer, the lowest excited singlet state (S ₁ ) of the compound (A) has a superior luminance lifetime of the light emitting device of the present disclosure, so the lowest excited singlet state of the compound (B) A higher energy level than the state (S ₁ ) is preferred.
From the above point of view, in the first layer, the lowest excited triplet state (T ₁ ) of the compound (A) has a superior luminance lifetime of the light-emitting device of the present disclosure, so the lowest excited triplet state of the compound (B) A higher energy level than the 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 (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 light-emitting device of the present disclosure has a superior luminance lifetime. more preferably contain a boron atom and a nitrogen atom in the ring, and still more preferably 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, since the light-emitting device of the present disclosure has a superior luminance lifetime. 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 is preferably a group consisting of a boron atom, an oxygen atom, a sulfur atom and a nitrogen atom, since the light-emitting device of the present disclosure has superior luminance lifetime. A polycyclic heterocyclic compound containing in the ring at least one selected from and more preferably a polycyclic heterocyclic compound containing a boron atom and a nitrogen atom in the ring More preferred are polycyclic heterocyclic compounds containing a boron atom and a nitrogen atom that does not form 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 3- to 12-ring heterocyclic compound, since the light-emitting device of the present disclosure has superior luminance lifetime. It 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:

It means that the group represented by is included.

The low-molecular-weight compound (B) is preferably a thermally activated delayed fluorescence (TADF) compound because the light-emitting device of the present disclosure has a superior luminance lifetime.
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 even more preferably 0.50 eV or less, because the luminance lifetime of the light-emitting device of the present disclosure is superior. _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), since the light-emitting device of the present disclosure has a superior luminance lifetime. A compound represented by formula (1-2) or formula (1-3) is preferred, and a compound represented by formula (1-2) is even more preferred.

Ar ¹ , Ar ² and Ar ³ are preferably monocyclic or bicyclic to hexacyclic aromatic hydrocarbons, or monocyclic or bicyclic A group obtained by removing one or more hydrogen atoms directly bonded to the atoms constituting the ring from a cyclic to hexacyclic heterocyclic compound, more preferably a monocyclic, bicyclic or tricyclic A group obtained by removing one or more hydrogen atoms directly bonded to atoms constituting a ring from an aromatic hydrocarbon or a monocyclic, bicyclic or tricyclic heterocyclic compound, more preferably A group obtained by removing one or more hydrogen atoms directly bonded to atoms constituting a ring from a monocyclic aromatic hydrocarbon or a monocyclic heterocyclic compound, particularly preferably from benzene, pyridine or diazabenzene , a group obtained by removing one or more hydrogen atoms directly bonded to a ring-constituting atom, particularly preferably a group obtained by removing one or more hydrogen atoms directly bonded to a ring-constituting atom 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, It is 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)- or an alkylene group, more preferably an oxygen atom, a sulfur atom, a group represented by -N(Ry)- or an alkylene group, particularly preferably an oxygen atom, a sulfur atom or -N ( 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.

Y ¹ , Y ² and Y ³ are all preferably an oxygen atom, a sulfur atom or a group represented by —N(Ry)—, since the light-emitting device of the present disclosure has a superior luminance lifetime, and Y 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, ^Z1 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 the formula (BP-1) or the formula (BP-2) because the polymer compound (B) can be easily synthesized and the luminance life of the light-emitting device of the present disclosure is superior. ) 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, a divalent heterocyclic group, a group represented by -N(R ^BP1 )-, 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. ^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 luminance life of the light-emitting device of the present disclosure is superior. 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) has an excellent luminance lifetime of the light-emitting device of the present disclosure, it is It is preferable to further include at least one selected structural unit. 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.
Since the polymer compound (B) is superior in the luminance lifetime of the light-emitting device of the present disclosure, the formula (Y
) preferably further comprises a structural unit represented by
The polymer compound (B) has excellent hole-transporting property of the polymer compound (B) and the luminance life of the light-emitting device of the present disclosure is more excellent. It is preferable to further include.
The polymer compound (B) has excellent hole-transporting property of the polymer compound (B), and the luminance life of the light-emitting device of the present disclosure is further excellent. It preferably further contains a structural unit represented by formula (Y) described below.

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 luminance life of the light emitting device of the present disclosure is longer. Since it is excellent, 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 %.
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 luminance life of the light-emitting device of the present disclosure is superior, it is preferably 10 to 99.95 mol %, more preferably 30 to 99.9 mol %. It is 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 30 mol %, because the hole transport property of the polymer compound (B) is excellent and the luminance life of the light emitting device of the present disclosure is more excellent. 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.

[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 light-emitting device of the present disclosure has a superior luminance lifetime.
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 containing a 5-membered ring in ring L ¹ is preferably 1 to 30, more preferably 1 to 10, more preferably 1 to 10, not including the number of carbon atoms in the substituents. 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, among the aromatic heterocycles exemplified in the section of the heterocyclic group described above, an aromatic heterocycle containing a 5-membered ring containing one or more nitrogen atoms in the ring, The aromatic heterocycle may have a substituent. Among these, the ring L ¹ is preferably an aromatic heterocyclic ring containing a 5-membered ring containing 2 or more and 4 or less nitrogen atoms in the ring, because the luminance life of the light-emitting device of the present disclosure is superior, More preferably an aromatic heterocycle containing a 5-membered ring containing 2 or 3 nitrogen atoms in the ring, still more preferably an aromatic heterocycle containing a 5-membered ring containing 3 nitrogen atoms in the ring and these rings may have a substituent.
Ring L ¹ is preferably a pyrrole ring, a diazole ring, a triazole ring, or a tetrazole ring, more preferably a diazole ring, a triazole ring, or a tetrazole ring, since the light-emitting device of the present disclosure has a superior luminance lifetime, A diazole ring or a triazole ring is more preferred, and a triazole ring is particularly 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, since the light-emitting element of the present disclosure has a superior luminance lifetime. or a 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 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 the 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 a monocyclic, bicyclic or tricyclic (preferably an aromatic heterocycle containing a 5- or 6-membered ring) of the formula, 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, particularly A dibenzothiophene ring or a dibenzofuran ring is preferable, and these rings may have a substituent.
Ring L ² is preferably an aromatic hydrocarbon ring containing a 5- or 6-membered ring, or an aromatic heterocyclic It is preferably a ring, and these rings may have a substituent.
Ring L ² is preferably a monocyclic, bicyclic or tricyclic aromatic hydrocarbon ring (preferably a 5- or 6-membered ring), since the light-emitting device of the present disclosure has a more excellent luminance lifetime. aromatic hydrocarbon ring containing), or a monocyclic, bicyclic or tricyclic aromatic heterocycle (preferably an aromatic heterocycle containing a 5- or 6-membered ring), more preferably , 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 dibenzothiophene ring or a dibenzofuran ring, these rings having a substituent may be
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 luminance lifetime of the light-emitting device of the present disclosure is more excellent, the ring L ¹ is a pyrrole ring, diazole ring, triazole ring or tetrazole ring, and the ring L ² is a benzene ring, a fluorene ring, a pyridine ring, a diazabenzene ring, or a carbazole ring. ring, dibenzofuran ring or dibenzothiophene ring, ring L ¹ is diazole ring or triazole ring, and ring L ² is benzene ring, fluorene ring, pyridine ring, diazabenzene ring, carbazole ring, dibenzofuran ring or It is more preferably a dibenzothiophene ring, ring L ¹ is a triazole ring, and ring L ² is a benzene ring, fluorene ring, pyridine ring, diazabenzene ring, carbazole ring, dibenzofuran ring or dibenzothiophene ring. More preferably, ring L ¹ is a triazole ring, and ring L ² is particularly preferably a benzene ring, dibenzothiophene ring or dibenzofuran 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 because the luminance lifetime of the light-emitting device of the present disclosure is better.
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 the ring L ¹ and the ring L ² should have a primary substituent, but since the luminance life of the light-emitting device of the present disclosure is superior, the ring L ¹ and the ring L ² having a plurality of rings may be used. At least two of them 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 At least two of the plurality of rings L ¹ have a primary substituent, or at least two of the plurality of rings L ² have a primary substituent, so that the disclosed light-emitting device has a better luminance lifetime. Preferably, all of the multiple rings L ¹ have a primary substituent, or more preferably all of the multiple rings L ² have a primary substituent, and all of the multiple rings L ¹ have It is more preferred to have 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 luminance life of the light-emitting device of the present disclosure is superior. , 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 luminance lifetime of the light-emitting element of the present disclosure is The number is preferably 1 to 18, more preferably 2 to 12, even more preferably 3 to 6, because it is more excellent.
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 luminance lifetime of the light-emitting element of the present disclosure is The number is preferably 1 to 12, more preferably 1 to 8, even more preferably 2 to 4, because it is more excellent.

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, 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 (hereinafter also referred to as "structural unit (A)") having a group obtained by removing one or more hydrogen atoms from the metal complex represented by formula (1). 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 the formula (AP-1) or the 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 (AP -1) is a structural unit.

[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). , preferably 0.1 to 99 mol%, more preferably 0.5 to 90 mol%, still more preferably 1 to 70 mol%, because the luminance life of the light-emitting device of the present disclosure is better, Especially 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) has an excellent luminance lifetime of the light-emitting device of the present disclosure, it is It is preferable to further include at least one selected structural unit. That is, the polymer compound (A) contains 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.
The polymer compound (A) preferably further contains a structural unit represented by the below-described formula (Y), since the light-emitting device of the present disclosure has a more excellent luminance lifetime.
The polymer compound (A) has excellent hole-transporting property of the polymer compound (A), and the light-emitting device of the present disclosure has a more excellent luminance life. It is preferable to further include.
Since the polymer compound (A) has excellent hole-transporting property of the polymer compound (A) and the luminance lifetime of the light-emitting device of the present disclosure is superior, the structural unit represented by the formula (X) below and It is preferable to further include a structural unit represented by formula (Y) described below.

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 can be any range as long as 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 luminance life of the light emitting device of the present disclosure is longer. Since it is excellent, 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 %.
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 luminance life of the light emitting device of the present disclosure is more excellent, it is preferably 1 to 99.9 mol%, more preferably 10 to 10 mol%. It is 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 30 mol %, because the hole transport property of the polymer compound (A) is excellent and the luminance life of the light emitting device of the present disclosure is more excellent. 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 a structural unit other than the structural unit (A), the structural unit represented by formula (X), and the structural unit represented by formula (Y).

[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)>
The first layer is a compound represented by the formula (H-1), and at least one selected from the group consisting of structural units represented by the formula (X) and structural units represented by the formula (Y) It may further contain at least one selected from the group consisting of polymer compounds containing structural units of species.
Since the luminance lifetime of the light-emitting element of the present disclosure is superior, the first layer includes the compound (A), the compound (B), the compound represented by the formula (H-1), and the compound represented by the formula (X). Consists of a polymer compound (hereinafter also referred to as "first polymer compound") containing at least one structural unit selected from the group consisting of structural units represented by the formula (Y) and structural units represented by formula (Y) and at least one compound selected from the group (hereinafter also referred to as "first compound") and a layer (hereinafter also referred to as "layer (1)"). That is, the layer (1) is a layer containing the compound (A), the compound (B), and the first compound.
The layer (1) 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) may be within a range in which the layer (1) functions. The total content of the compound (A), the compound (B) and the first compound in the layer (1) may be, for example, 1 to 100% by mass based on the total amount of the layer (1), and the present disclosure is preferably 10 to 100% by mass, more preferably 30 to 100% by mass, even more preferably 50 to 100% by mass, and particularly preferably 70 to 100% by mass. %, particularly preferably 90 to 100% by mass.
The total content of the compound (A) and the compound (B) in the layer (1) may be within a range in which the layer (1) functions. The total content of the compound (A) and the compound (B) in the layer (1) is, when the total content of the compound (A), the compound (B) and the first compound is 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 light-emitting device of the present disclosure has a more excellent luminance life. , 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) may be within a range where the function of the layer (1) is exhibited. The content of the compound (B) in the layer (1) is, for example, 0.01 to 99 parts by mass when the total content of the compound (A) and the compound (B) is 100 parts by mass. Since the disclosed light-emitting device has an excellent luminance lifetime, the amount 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. Especially preferably 1 to 30 parts by mass, particularly preferably 2 to 20 parts by mass.

In layer (1), 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 layer (1), resulting in better luminance lifetime of the light emitting device of the present disclosure.

In the layer (1), taking the light-emitting material as an example, the first compound, the compound (A), and the compound (B) electrically interact to efficiently convert the first compound to the compound (A). By transferring electric energy to and further efficiently transferring electric energy from the compound (A) to the compound (B), the compound (B) can be made to emit light more efficiently, and the luminance of the light-emitting element of the present disclosure Better life.

From the above point of view, in the layer (1), the light-emitting device of the present disclosure has a superior luminance lifetime, so the first compound has at least It is more preferable to have one function.
From the above viewpoint, in the layer (1), the luminance life of the light-emitting device of the present disclosure is superior, so the compound (A) has at least It is more preferable to have one function.
From the above point of view, in the layer (1), the compound (B) more preferably has light-emitting properties, since the light-emitting device of the present disclosure has a superior luminance life.
From the above point of view, in the layer (1), the lowest excited singlet state (S ₁ ) of the first compound has a superior luminance lifetime of the light-emitting device of the present disclosure, so the lowest excited singlet state of the compound (A) A higher energy level than the state (S ₁ ) is preferred.
From the above point of view, in the layer (1), the lowest excited singlet state (S ₁ ) of the first compound has a superior luminance lifetime of the light emitting device of the present disclosure, so the lowest excited singlet state of the compound (B) A higher energy level than the state (S ₁ ) is preferred.
From the above point of view, in the layer (1), the lowest excited singlet state (S ₁ ) of the compound (A) has a superior luminance lifetime of the light emitting device of the present disclosure, so the lowest excited singlet state of the compound (B) A higher energy level than the state (S ₁ ) is preferred.
From the above point of view, in the layer (1), the lowest excited triplet state (T ₁ ) of the first compound has a superior luminance lifetime of the light emitting device of the present disclosure, so the lowest excited triplet state of the compound (A) A higher energy level than the state (T ₁ ) is preferred.
From the above point of view, in the layer (1), the lowest excited triplet state (T ₁ ) of the first compound has a superior luminance lifetime of the light emitting device of the present disclosure, so the lowest excited triplet state of the compound (B) A higher energy level than the state (T ₁ ) is preferred.
From the above point of view, in the layer (1), the lowest excited triplet state (T ₁ ) of the compound (A) has a superior luminance lifetime of the light emitting device of the present disclosure, so the lowest excited triplet state of the compound (B) A higher energy level than the 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 layer (1), the first compound is preferably a host material, an assisting dopant material, or a dopant material, and is preferably a host material or an assisting dopant material, because the light-emitting device of the present disclosure has a superior luminance lifetime. More preferably, it is a host material.
In the first layer (eg, layer (1)), the compound (A) is preferably a host material, an assist dopant material, or a dopant material, since the light-emitting device of the present disclosure has a superior luminance lifetime.
In the first layer (e.g., layer (1)), the metal complex represented by formula (1) is a host material, an assist dopant material, or a dopant material because the light-emitting device of the present disclosure has a superior luminance lifetime. is preferred, the assist dopant material or dopant material is more preferred, and the assist dopant material is even more preferred.
In the first layer (e.g., layer (1)), the polymer compound (A) is preferably a host material, an assist dopant material, or a dopant material because the light-emitting device of the present disclosure has a superior luminance lifetime, It is more preferably a host material or an assist dopant material, and even more preferably an assist dopant material.
In the first layer (e.g., layer (1)), the polymer compound (A) may have at least one function selected from a host material, an assist dopant material, and a dopant material. It may have at least two functions of the assist dopant material and the dopant material, or may have three functions of the host material, the assist dopant material and the dopant material.
In the first layer (eg, layer (1)), the compound (B) is preferably a host material, an assist dopant material, or a dopant material, since the light-emitting device of the present disclosure has a superior luminance lifetime.
In the first layer (e.g., layer (1)), the low-molecular-weight compound (B) is preferably a host material, an assist dopant material, or a dopant material, since the light-emitting device of the present disclosure has a superior luminance lifetime. It is more preferably an assist dopant material or a dopant material, and even more preferably a dopant material.
In the first layer (e.g., layer (1)), the polymer compound (B) is preferably a host material, an assist dopant material, or a dopant material, because the light-emitting device of the present disclosure has a superior luminance lifetime. It is more preferably a host material or a dopant material, and even more preferably a dopant material.
In the first layer (e.g., layer (1)), the polymer compound (B) may have at least one function selected from a host material, an assist dopant material, and a dopant material. It may have at least two functions of the assist dopant material and the dopant material, or may have three functions of the host material, the assist dopant material and the 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 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 adjust the emission properties, charge transport properties, or charge injection properties of the light emitting device of the present disclosure, resulting in better luminance lifetime of the light emitting device 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 assist dopant material to the dopant material, the dopant material can emit light more efficiently, and the luminance lifetime of the light emitting device of the present disclosure is better.

From the above point of view, in the light-emitting element of the present disclosure, the luminance lifetime of the light-emitting element of the present disclosure is superior, so the host material contains at least one selected from hole injection properties, hole transport properties, electron injection properties, and electron transport properties. It is more preferable to have two functions.
From the above viewpoint, in the light-emitting device of the present disclosure, since the luminance life of the light-emitting device of the present disclosure is superior, the assist dopant material is 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 element of the present disclosure, the dopant material preferably has light-emitting properties because the luminance life of the light-emitting element of the present disclosure is superior.
From the above point of view, in the light-emitting device of the present disclosure, the lowest excited singlet state (S ₁ ) of the host material has a superior luminance lifetime of the light-emitting device of the present disclosure, so the lowest excited singlet state of the assist dopant material ( S ₁ ) is preferably at a higher energy level.
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 superior luminance lifetime of the light-emitting device of the present disclosure, so the lowest excited singlet state of the dopant material (S ₁ ) Higher energy levels are preferred.
From the above viewpoint, in the light-emitting device of the present disclosure, the lowest excited singlet state (S ₁ ) of the assist dopant material has a superior luminance lifetime of the light-emitting device 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 viewpoint, in the light-emitting device of the present disclosure, the lowest excited triplet state (T ₁ ) of the host material has a superior luminance lifetime of the light-emitting device of the present disclosure, so the lowest excited triplet state of the assist dopant material ( T ₁ ) is preferably a higher energy level.
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 superior luminance lifetime of the light-emitting device of the present disclosure, so the lowest excited triplet state (T ₁ ) Higher energy levels are preferred.
From the above viewpoint, in the light-emitting device of the present disclosure, the lowest excited triplet state (T ₁ ) of the assist dopant material has a superior luminance lifetime of 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.

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 is preferably 0.1 to 99% by mass, more preferably 0.5 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. Since the luminance life of the present disclosure is more excellent, it is preferably 0.05 to 90 parts by mass, more preferably 0.1 to 90 parts by mass. 70 parts by mass, 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 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 may be, for example, 1 to 100% by mass based on the total amount of the first layer, and is preferably 10 to 100% by mass, more preferably 30 100% 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 luminance life of the light emitting device of the present disclosure is more excellent. 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 to 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 luminance life of the light emitting device of the present disclosure is more excellent, so it is preferably 0.05 to 90 parts by mass, and more It is preferably 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.

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

The aryl group in Ar ^H1 and Ar ^H2 is preferably directly bonded to an atom constituting a ring of monocyclic or 2- to 7-cyclic aromatic hydrocarbons, because the luminescence lifetime of the light-emitting device of the present disclosure is superior. a group from which one hydrogen atom has been removed, more preferably a monocyclic or bi- to five-ring aromatic hydrocarbon group from which one hydrogen atom directly bonded to an atom constituting a ring has been removed, More preferably, it is a group obtained by removing one hydrogen atom directly bonded to a ring-constituting atom from a monocyclic, bicyclic or tricyclic aromatic hydrocarbon, and these groups have a substituent. may be
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, dihydrophenanthrene, fluorene, benzanthracene, benzophenanthrene or benzofluorene, from which one hydrogen atom directly bonded to a ring-constituting atom is removed, more preferably benzene, naphthalene, anthracene, phenanthrene, dihydrophenanthrene or A group obtained by removing one hydrogen atom directly bonded to a ring-constituting atom from fluorene, particularly preferably benzene, naphthalene or anthracene, with one hydrogen atom directly bonded to a ring-constituting atom removed. 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 heterocyclic 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 ring skeleton (b), more preferably a single to an atom constituting a ring from a cyclic or bi- to pentacyclic heterocyclic compound (preferably a monocyclic or bi- to pentacyclic heterocyclic compound that does not contain a condensed heterocyclic skeleton (b)) a group excluding one directly bonded hydrogen atom, more preferably a monocyclic, bicyclic or tricyclic heterocyclic compound (preferably a single A cyclic, bicyclic or tricyclic heterocyclic compound) from which one hydrogen atom directly bonded to an atom constituting the ring is removed, particularly preferably a tricyclic heterocyclic compound ( Preferably, it is a group obtained by removing one hydrogen atom directly bonded to a ring-constituting atom from a tricyclic heterocyclic compound that does not contain a condensed heterocyclic skeleton (b)), and these groups are substituents may have
The monovalent heterocyclic groups in Ar ^H1 and Ar ^H2 are preferably furan, thiophene, oxadiazole, thiadiazole, pyrrole, diazole, triazole, pyridine, diazabenzene, triazine, azanaphthalene, diazanaphthalene, benzofuran, benzothiophene, indole, azaindole, diazaindole, benzodiazole, benzothiadiazole, benzotriazole, dibenzofuran, dibenzothiophene, carbazole, azacarbazole, diazacarbazole, phenoxazine, phenothiazine, 9,10-dihydroacridine, 5,10-dihydrophenazine, azaanthracene, diazaanthracene, azaphenanthrene, diazaphenanthrene, benzocarbazole, azabenzocarbazole, diazabenzocarbazole, benzonaphthofuran, benzonaphthothiophene, a group obtained by removing one hydrogen atom directly bonded to a ring-constituting atom from 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-dihydro Phenazine, benzocarbazole, azabenzocarbazole, diazabenzocarbazole, benzonaphthofuran, benzonaphthothiophene, dibenzocarbazole, indolocarbazole, indenocarbazole, azaindolocarbazole, diazaindolocarbazole, azaindenocarbazole or diaza a group obtained by removing one hydrogen atom directly bonded to an atom constituting a ring from indenocarbazole, more preferably pyridine, diazabenzene, triazine, azanaphthalene, diazanaphthalene, dibenzofuran, dibenzothiophene, carbazole, azacarbazole , diazacarbazole, phenoxazine, phenothiazine, 9,10-dihydroacridine or 5,10-dihydrophenazine with one hydrogen atom directly bonded to a ring-constituting atom removed, particularly preferably pyridine, diazabenzene, triazine, azanaphthalene, diazanaphthalene, dibenzofuran, dibenzothiophene, or carbazole without one hydrogen atom directly bonded to a ring-constituting atom; is a group excluding one hydrogen atom directly bonded to the atoms constituting the, 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 groups, because the luminance lifetime of the light-emitting device of the present disclosure is superior. or a monovalent heterocyclic group, and these groups may have a substituent.
The aryl group and monovalent heterocyclic group for Ar ^H1 and Ar ^H2 are monocyclic, bicyclic or tricyclic aromatic hydrocarbons, or from a monocyclic, bicyclic or tricyclic heterocyclic compound (preferably a monocyclic, bicyclic or tricyclic heterocyclic compound that does not contain a condensed heterocyclic skeleton (b)), A group having one hydrogen atom directly bonded to a ring-constituting atom is preferably removed, and the ring is composed of benzene, naphthalene, fluorene, pyridine, diazabenzene, triazine, azanaphthalene, diazanaphthalene, dibenzofuran, dibenzothiophene, or carbazole. is more preferably a group excluding one hydrogen atom directly bonded to the atom to which Particularly preferably, these groups may have a substituent.

Preferred substituents that Ar ^H1 and Ar ^H2 may have are 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 )- 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 a group represented by -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 , 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, more preferably a divalent heterocyclic group, since the light-emitting device of the present disclosure has a superior luminance lifetime. is an arylene group or a divalent heterocyclic group, and these groups may have a substituent.

Among the divalent groups in L ^H1 , the arylene group is preferably a monocyclic or bi- to seven-cyclic aromatic hydrocarbon ring-constituting atom, since the light-emitting device of the present disclosure has superior luminance lifetime. A group in which 2 hydrogen atoms directly bonded are removed, more preferably a group in which 2 hydrogen atoms directly bonded to atoms constituting a ring are removed from a monocyclic or bi- to pentacyclic aromatic hydrocarbon and more preferably a group obtained by removing two hydrogen atoms directly bonded to the atoms constituting the ring from a monocyclic, bicyclic or tricyclic aromatic hydrocarbon, and these groups are substituents may have
Among the divalent groups in L ^H1 , arylene groups are preferably benzene, naphthalene, anthracene, phenanthrene, dihydrophenanthrene, fluorene, benzanthracene, benzophenanthrene, benzofluorene, since the light-emitting device of the present disclosure has superior luminance lifetime. , dibenzoanthracene, dibenzophenanthrene, dibenzofluorene, indenofluorene or benzofluoranthene, from which two hydrogen atoms directly bonded to the atoms constituting the ring are removed, more preferably benzene, naphthalene, 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, dihydro A group obtained by removing two hydrogen atoms directly bonded to ring-constituting atoms from phenanthrene or fluorene, particularly preferably benzene, naphthalene or anthracene, and removing two hydrogen atoms directly bonded to ring-constituting atoms. These groups may have substituents.

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 , the divalent heterocyclic group is preferably a monocyclic or bi- to seven-ring heterocyclic compound (preferably , a monocyclic or 2- to 7-ring heterocyclic compound that does not contain a condensed heterocyclic skeleton (b)) from which two hydrogen atoms directly bonded to the atoms (preferably carbon atoms) constituting the ring are removed group, more preferably a monocyclic or bi- to pentacyclic heterocyclic compound (preferably a monocyclic or bi- to pentacyclic heterocyclic compound that does not contain a condensed heterocyclic skeleton (b) A group obtained by removing two hydrogen atoms directly bonded to atoms (preferably carbon atoms) constituting a ring from a compound), more preferably a monocyclic, bicyclic or tricyclic heterocyclic compound ( Preferably, a hydrogen atom 2 directly bonded to an atom (preferably a carbon atom) constituting a ring from a monocyclic, bicyclic or tricyclic heterocyclic compound that does not contain a condensed heterocyclic skeleton (b) is a group excluding one, particularly preferably a tricyclic heterocyclic compound (preferably a tricyclic heterocyclic compound that does not contain a condensed heterocyclic skeleton (b)), atoms constituting a ring (preferably a carbon atom) without two hydrogen atoms directly bonded thereto, and these groups may have a substituent.
Among the divalent groups in L ^H1 , a divalent heterocyclic group is preferably furan, thiophene, oxadiazole, thiadiazole, pyrrole, diazole, triazole, or pyridine because the light-emitting device of the present disclosure has superior luminance lifetime. , 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, benzo directly bonded to a ring-constituting atom (preferably a carbon atom) of naphthothiophene, dibenzocarbazole, indolocarbazole, indenocarbazole, azaindolocarbazole, diazaindolocarbazole, azaindenocarbazole or diazaindenocarbazole; a group with two hydrogen atoms removed, more preferably pyridine, diazabenzene, triazine, azanaphthalene, diazanaphthalene, dibenzofuran, dibenzothiophene, carbazole, azacarbazole, diazacarbazole, phenoxazine, phenothiazine, 9,10 - dihydroacridine, 5,10-dihydrophenazine, benzocarbazole, azabenzocarbazole, diazabenzocarbazole, benzonaphthofuran, benzonaphthothiophene, dibenzocarbazole, indolocarbazole, indenocarbazole, azaindolocarbazole, diazaindro carbazole, azaindenocarbazole or diazaindenocarbazole without two hydrogen atoms directly bonded to atoms (preferably carbon atoms) constituting the ring, more preferably pyridine, diazabenzene, triazine, aza Atoms (preferably carbon atoms) forming a ring from naphthalene, 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) A group in which two hydrogen atoms directly bonded to are removed, and particularly preferably a group in which two hydrogen atoms directly bonded to ring-constituting atoms (preferably carbon atoms) 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), the polymer compound (B), and the polymer compound containing a structural unit having a cross-linking group. , the structural unit (B) and a structural unit having a cross-linking group are more preferably polymer compounds.

The first polymer compound preferably contains a structural unit represented by formula (Y) because the light-emitting device of the present disclosure has a superior luminance lifetime.
When the first polymer compound contains the 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 the structural unit represented by formula (Y), the content of the structural unit represented by formula (Y) contained in the first polymer compound is It is, for example, 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 luminance life of the light-emitting device of the present disclosure is superior. It is preferably 30 to 100 mol %, 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 in one kind, or may be contained in two or more kinds.

The first polymer compound contains a structural unit represented by formula (X), since the first polymer compound has excellent hole-transport properties and the light-emitting device of the present disclosure has excellent luminance life. 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 it functions as a molecular compound. 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. It is preferably 0.05 to 90 mol %, more preferably 0.1 to 70 mol %, even more preferably 0.2 to 50 mol %, particularly preferably 0.05 to 90 mol %, more preferably 0.2 to 50 mol %, particularly preferably 0.05 to 90 mol %, more preferably 0.1 to 70 mol %, further preferably 0.2 to 50 mol %. 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 an excellent hole-transport property and the light-emitting device of the present disclosure has an excellent luminance lifetime, the structural unit represented by the 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 It is preferably 10 to 100 mol%, more preferably 30 to 100 mol%, even more preferably 50 to 100 mol%, and particularly preferably 70 to 100 mol%, because the luminance life of the device is better. and particularly preferably 90 to 100 mol %.

The arylene group represented by the structural unit Ar ^Y1 represented by the formula (Y) is preferably a monocyclic or bicyclic to hexacyclic aromatic group because the light-emitting element of the present disclosure has a superior luminance lifetime. a group obtained by removing two hydrogen atoms directly bonded to atoms 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 two hydrogen atoms directly bonded to atoms constituting the ring. and particularly preferably a group obtained by removing two hydrogen atoms directly bonded to ring-constituting atoms from benzene, phenanthrene, dihydrophenanthrene or fluorene, and these groups have a substituent and good too.
The divalent heterocyclic group represented by Ar ^Y1 preferably has a ring selected from monocyclic or bicyclic to hexacyclic heterocyclic compounds, since the light-emitting element of the present disclosure has superior luminance lifetime. A group excluding two hydrogen atoms directly bonded to constituent atoms, more preferably a hydrogen directly bonded to a ring-constituting atom from a monocyclic, bicyclic or tricyclic heterocyclic compound groups with two 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, or carbazole. , dibenzofuran, dibenzothiophene, phenoxazine or phenothiazine, excluding two hydrogen atoms directly bonded to ring-constituting atoms (preferably carbon atoms or nitrogen atoms, more preferably carbon atoms), and these groups may have a substituent.
In the divalent group in which at least one arylene group and at least one divalent heterocyclic group represented by Ar ^Y1 are directly bonded, the preferred ranges of the arylene group and the divalent heterocyclic group are, respectively, It is the same as the preferred range of the arylene group and divalent heterocyclic group represented by Ar ^Y1 .

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

Ar ^Y1 is preferably an optionally substituted arylene group because the light-emitting device of the present disclosure has a superior luminance lifetime.

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 light-emitting device of the present disclosure has superior luminance lifetime. A group obtained by removing one hydrogen atom directly bonded to a ring-constituting atom from a hydrocarbon, more preferably a monocyclic, bicyclic or tricyclic aromatic hydrocarbon A group from which one hydrogen atom directly bonded to an atom has been removed, more preferably from benzene, naphthalene, anthracene, phenanthrene, dihydrophenanthrene or fluorene, from which one hydrogen atom directly bonded to a ring-constituting atom has been removed group, particularly preferably benzene, phenanthrene, dihydrophenanthrene or fluorene, with one hydrogen atom directly bonded to a ring-constituting atom removed, these groups further having a substituent good too.
The monovalent heterocyclic group in the substituent that the group represented by Ar ^Y1 may have is preferably monocyclic or bicyclic to hexacyclic because the luminance lifetime of the light-emitting device of the present disclosure is superior. is a group obtained by removing one hydrogen atom directly bonded to a ring-constituting atom from a heterocyclic compound of the formula, 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 with one hydrogen atom directly bonded to a ring-constituting atom (preferably a carbon atom or a nitrogen atom) removed, particularly preferably pyridine or 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 further 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 light-emitting device of the present disclosure has a superior luminance lifetime.

[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 or a cycloalkyl group, since the light-emitting element of the present disclosure has superior luminance lifetime. , an alkoxy group, a cycloalkoxy group, an aryl group, an aryloxy group, a monovalent heterocyclic group, a substituted amino group or a fluorine atom, more preferably an alkyl group, a cycloalkyl group, an aryl group, a monovalent heterocyclic ring or a substituted amino group, more preferably an alkyl group, a cycloalkyl group or an aryl group, particularly preferably an alkyl group, and these groups may have a substituent.

R ^Y2 is preferably an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, a monovalent heterocyclic group, or a substituted amino group, since the light-emitting device of the present disclosure has a superior luminance lifetime; More preferably an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, still more preferably an alkyl group, a cycloalkyl group or an aryl group, these groups having a substituent good too.

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 light-emitting element of the present disclosure has a superior luminance lifetime. and more preferably a group represented by -C(R ^Y2 ) ₂ -.

Examples of structural units represented by formula (Y) include structural units comprising at least one arylene group represented by formulas (Y-101)-(Y-141), and formulas (Y-201)-( Y-209) consisting of at least one divalent heterocyclic group, at least one arylene group represented by formulas (Y-301) to (Y-306) and at least one Structural units composed of a divalent group directly bonded to a divalent heterocyclic group are 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 light emitting device of the present disclosure has a superior luminance life, It is more preferably an integer of 0 to 3, still more preferably an integer of 0 to 2, and particularly preferably 0 or 1.

R ^X1 , R ^X2 and R ^X3 are preferably an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, more preferably an aryl group or It is 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 light-emitting device of the present disclosure has superior luminance lifetime.
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 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 , Buchwald reaction, Stille reaction, Negishi reaction, Kumada reaction, and other coupling reactions using a transition metal catalyst.
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, and column chromatography.

[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 comprises 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 from. 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). In the first composition, the hole-transporting material, hole-injecting material, electron-transporting material, electron-injecting material and light-emitting material are different from compound (A).
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 its derivatives, N,N'-di-1-naphthyl-N,N'-diphenylbenzidine (α-NPD), and N,N'-diphenyl-N, Aromatic amine compounds such as N'-di(m-tolyl)benzidine (TPD) can be mentioned.
Polymer compounds include, for example, polyvinylcarbazole and derivatives thereof; polyarylenes and derivatives thereof having aromatic amine structures in side chains or main chains. The polymer compound may be a compound having electron-accepting moieties such as fullerene, tetrafluorotetracyanoquinodimethane, tetracyanoethylene and trinitrofluorenone bound thereto.
When the first composition contains a hole-transporting material, the content of the hole-transporting material is usually 1 when the total content of the compound (B) and the compound (A) is 100 parts by mass. ~10000 parts by mass.
The hole transport materials may be used singly or in combination of two or more.

(Electron transport material)
Electron transport materials are classified into low-molecular-weight compounds and high-molecular-weight compounds. The electron transport material may have a cross-linking group.
Examples of low-molecular-weight compounds include metal complexes having 8-hydroxyquinoline as a ligand, oxadiazole, anthraquinodimethane, benzoquinone, naphthoquinone, anthraquinone, tetracyanoanthraquinodimethane, fluorenone, diphenyldicyanoethylene and diphenoquinone. , as well as derivatives thereof.
Polymer compounds include, for example, polyphenylene, polyfluorene, and derivatives thereof. The polymeric compounds may be doped with metals.
When the first composition contains an electron-transporting material, the content of the electron-transporting material is usually 1 to 10,000 parts when the total content of the compound (B) and the compound (A) is 100 parts by mass. part by mass.
The electron transport materials may be used singly or in combination of two or more.

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

- Ion doping The hole-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 type of ions to be doped into the hole injection material or the electron injection material is, for example, an anion for the hole injection material, and a cation 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 10000 parts by mass when the total content of the compound (B) and the compound (A) is 100 parts by mass. is.
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 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 when the total content of the compound (B) and the compound (A) is 100 parts by mass. ~10 parts by mass.
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 compound (B), compound (A), and a solvent (hereinafter also referred to as “first ink”).
The first ink may contain one type of compound (B), compound (A) and solvent, respectively, or may contain two or more types.
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 may further contain at least one selected from the group consisting of 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. good.
The first ink may contain one type of hole transport material, hole injection material, electron transport material, electron injection material, light emitting material, and antioxidant, respectively, or contain two or more types. may have been
Examples and preferred ranges of the hole-transporting material, the electron-transporting material, the hole-injecting material, the electron-injecting material, the light-emitting material, and the antioxidant, which the first ink may further comprise, are described in the first composition, respectively. are the same as the examples and preferred ranges of the hole transport material, electron transport material, hole injection material, electron injection material, light emitting material and antioxidant contained in .
The contents of the hole-transporting material, the electron-transporting material, the hole-injecting material, the electron-injecting material, and the light-emitting material, which the first ink may further contain, are each the total of the compound (B) and the compound (A) When the content of is 100 parts by mass, it is usually 1 to 10000 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 total content of the compound (B) and the compound (A) is 100 parts by mass. is. The content of the first compound that the first ink may further contain is, for example, 0 when the total content of the compound (A), the compound (B) and the first compound is 100 parts by mass. .1 to 99.99 parts by mass, preferably 1 to 99.9 parts by mass, more preferably 10 to 99.5 parts by mass, since the light-emitting device of the present disclosure has a more excellent luminance life; It is preferably 30 to 99 parts by mass, particularly preferably 50 to 95 parts by mass, particularly preferably 70 to 90 parts by mass.

<Second layer>
In the light-emitting device of the present disclosure, the second layer is a layer containing a crosslinked compound having a crosslinkable group. The second layer may contain only one type of crosslinked compound of a compound having a crosslinkable group, or may contain two or more types.

The content of the crosslinked compound having a crosslinkable group in the second layer may be within a range in which the function as the second layer is exhibited. The total content of the crosslinked product of the compound having a crosslinkable group in the second layer may be, for example, 1 to 100% by mass based on the total amount of the second layer, and the luminance lifetime of the light emitting device of the present disclosure is more excellent, 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 is 90 to 100% by mass.

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

In the compound having a cross-linking group, the cross-linking group is preferably at least one selected from Group A of cross-linking groups, because the cross-linking property of the compound having a cross-linking group is superior and the luminance life of the light-emitting device of the present disclosure is superior. One cross-linking group (that is, at least one cross-linking group selected from cross-linking groups represented by formulas (XL-1) to (XL-19)), more preferably formula (XL-1) ~ Formula (XL-4), Formula (XL-7) ~ Formula (XL-10) or Formula (XL-14) ~ Formula (XL-19) is a cross-linking group, more preferably Formula ( XL-1), formula (XL-3), formula (XL-7), formula (XL-9), formula (XL-10), or represented by formulas (XL-16) to (XL-19) A cross-linking group, particularly preferably a cross-linking group represented by formula (XL-1), formula (XL-7), formula (XL-10) or formula (XL-16) or formula (XL-17) and particularly preferably a cross-linking group represented by formula (XL-1), formula (XL-16) or formula (XL-17).

In Group A of the cross-linking group, examples and preferred ranges of substituents that the cross-linking group may have are the same as examples and preferred ranges of substituents that the group represented by Ar ^Y1 may have.
The compound having a cross-linking group may contain only one cross-linking group, or may contain two or more cross-linking groups.

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

The structural unit having a cross-linking group is preferably a structural unit represented by formula (Z) or a structural unit represented by formula (Z'), since the light-emitting device of the present disclosure has a superior luminance lifetime.

Structural unit n represented by formula (Z) is usually an integer of 1 to 10, and is preferably an integer of 1 to 7, more preferably 1, because the light-emitting device of the present disclosure has a superior luminance life. It is an integer of to 4, more preferably 1 or 2, and particularly preferably 2.
nA is usually an integer of 0 to 10, and is preferably an integer of 0 to 7, more preferably an integer of 0 to 4, and still more preferably 0, because the light-emitting device of the present disclosure has a superior luminance lifetime. An integer from ~2.

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

Examples and preferred ranges of the arylene group represented by ^LA include examples and preferred ranges of the arylene group represented by Ar ^Y1 . The arylene group represented by ^LA is preferably a phenylene group or a fluorenediyl group because the light-emitting device of the present disclosure has a superior luminance lifetime, and these groups may have a substituent.
Examples and preferred ranges of the divalent heterocyclic group represented by ^LA are the same as examples and preferred ranges of the divalent heterocyclic group represented by Ar ^Y1 .
^LA is preferably an arylene group or an alkylene group, more preferably a phenylene group, because it facilitates the synthesis of a polymer compound having a crosslinkable group and the luminance life of the light-emitting device of the present disclosure is superior. , a fluorenediyl group or an alkylene group, and these groups may have a substituent.

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

Examples and preferred ranges of substituents that groups represented by Ar ^Z , ^LA and R′ may have are the same as examples and preferred ranges of substituents that groups represented by Ar ^Y1 may have. is.
Examples and preferred ranges of the cross-linking group for X are the same as the examples and preferred range of the cross-linking group in the compound having a cross-linking group.

- Structural unit represented by formula (Z')

mA is usually an integer of 0 to 10, and preferably an integer of 0 to 7, more preferably an integer of 0 to 4, and still more preferably 0, because the light-emitting device of the present disclosure has a superior luminance lifetime. It is an integer of ∼2, particularly preferably 0 or 1, particularly preferably 0.
m is usually an integer of 0 to 10, preferably an integer of 0 to 7, more preferably an integer of 0 to 4, and still more preferably 0, because the light-emitting device of the present disclosure has a superior luminance lifetime. It is an integer of up to 2, and particularly preferably 0.
c is usually an integer of 0 to 10, and is preferably an integer of 0 to 5 because it facilitates the synthesis of a polymer compound having a cross-linking group and the luminance life of the light emitting device of the present disclosure is superior. , more preferably an integer of 0 to 2, more preferably 0 or 1, and particularly preferably 0.

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

Ar ⁴ and Ar ⁶ are preferably an arylene group optionally having a substituent, since the light-emitting device of the present disclosure has a superior luminance lifetime.
Examples and preferred ranges of arylene groups for Ar ⁴ and Ar ⁶ are the same as examples and preferred ranges of arylene groups for Ar ^X1 , Ar ^X2 , Ar ^X3 and Ar ^X4 .
Examples and preferred ranges of the divalent heterocyclic group for Ar ⁴ and Ar ⁶ are the same as examples and preferred ranges for the divalent heterocyclic group for Ar ^X1 , Ar ^X2 , Ar ^X3 and Ar ^X4 .

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

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

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

Examples of structural units having a cross-linking group include structural units represented by the following formulas.

(Other structural units)
A polymer compound having a cross-linking group (preferably a polymer compound containing a structural unit having a cross-linking group) has a superior luminance lifetime of the light-emitting device of the present disclosure, so the structure represented by formula (X) It preferably contains at least one structural unit selected from the group consisting of units and structural units represented by formula (Y), and the structural unit represented by formula (X) and the structure represented by formula (Y) It preferably contains at least one structural unit selected from the group consisting of units and a structural unit having a cross-linking group.
A polymer compound having a cross-linking group comprises at least one structural unit selected from the group consisting of structural units represented by formula (X) and structural units represented by formula (Y), and a structural unit having a cross-linking group. and the structural unit having a cross-linking group is preferably different from the structural unit represented by the formula (X) and the structural unit represented by the formula (Y).
A polymer compound having a cross-linking group preferably contains a structural unit represented by the formula (Y) because the light-emitting device of the present disclosure has a superior luminance life. It is more preferable to contain a structural unit having a group.
The polymer compound having a cross-linking group has excellent hole-transporting property of the polymer compound having a cross-linking group, and the luminance life of the light-emitting device of the present disclosure is superior, so the structural unit represented by the formula (X) is It preferably contains a structural unit represented by formula (X) and a structural unit having a cross-linking group.
A polymer compound having a cross-linking group has an excellent hole-transport property of the polymer compound having a cross-linking group, and the luminance life of the light-emitting device of the present disclosure is further excellent, so the structural unit represented by formula (X) and It preferably contains a structural unit represented by formula (Y), and more preferably contains a structural unit represented by formula (X), a structural unit represented by formula (Y), and a structural unit having a cross-linking group. .

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

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

When the polymer compound having a cross-linking group contains a structural unit represented by formula (X) and/or a structural unit represented by formula (Y), and a structural unit having a cross-linking group, in formula (X) The total content of the structural unit represented by the formula (Y), the structural unit having a crosslinkable group, and the structural unit having a crosslinkable group may be within a range in which the function as a polymer compound having a crosslinkable group can be exhibited. When the polymer compound having a cross-linking group contains a structural unit represented by formula (X) and/or a structural unit represented by formula (Y), and a structural unit having a cross-linking group, in formula (X) The total content of the structural unit represented by the formula (Y) and the structural unit having a cross-linking group is based on the total content of the structural units contained in the polymer compound having a cross-linking group. , for example, 1 to 100 mol%, and the luminance life of the light emitting device of the present disclosure is more excellent, so it is preferably 10 to 100 mol%, more preferably 30 to 100 mol%, and still more preferably 50 to 100 mol%. 100 mol %, particularly preferably 70 to 100 mol %, particularly preferably 90 to 100 mol %.

Examples of polymer compounds having a cross-linking group include polymer compounds P-1 to P-12 shown in Table 4. Here, "other" means a structural unit represented by formula (Z), a structural unit represented by formula (Z'), a structural unit represented by formula (X), and a structural unit represented by formula (Y). means a structural unit other than the structural unit

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

The polymer compound having a cross-linking group may be a block copolymer, a random copolymer, an alternating copolymer, a graft copolymer, or may be in other forms. It is preferably a copolymer obtained by copolymerizing raw material monomers.
The example and preferred range of the polystyrene-equivalent number average molecular weight of the polymer compound having a cross-linking group are the same as the example and preferred range of the polystyrene-equivalent number average molecular weight of the first polymer compound. The example and preferred range of the polystyrene-equivalent weight average molecular weight of the polymer compound having a cross-linking group are the same as the example and preferred range of the polystyrene-equivalent weight average molecular weight of the first polymer compound.

(Method for Producing Polymer Compound Having Crosslinking Group)
A polymer compound having a cross-linking group can be produced by a method similar to the method for producing the first polymer compound.

[Low-molecular compound having a cross-linking group]
A low-molecular-weight compound having a cross-linking group is preferably a compound represented by the formula (Z'') because the light-emitting device of the present disclosure has a more excellent luminance lifetime. That is, the compound having a cross-linking group is preferably a compound represented by Formula (Z'').

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

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

[Second composition]
The second layer comprises a crosslinked compound having a crosslinkable group, and 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. It may be a layer containing a composition containing (hereinafter also referred to as "second composition"). In the second layer, the hole-transporting material, the hole-injecting material, the electron-transporting material, the electron-injecting material and the light-emitting material are different from crosslinked compounds having a crosslinking group.
The second composition contains each of a crosslinked compound having a crosslinkable group, a hole-transporting material, a hole-injecting material, an electron-transporting material, an electron-injecting material, a light-emitting material, and an antioxidant. 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 crosslinked compound having a crosslinkable group, the hole-transporting material, the hole-injecting material, the electron-transporting material, the electron-injecting material, the light-emitting material, and the antioxidant is The content may be within a range in which the function of the composition can be exhibited. In the second composition, the total content of the crosslinked compound having a crosslinkable group, 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, It may be 1 to 100% by mass, 10 to 100% by mass, or 30 to 100% by mass, more preferably 50 to 100% by mass, based on the total amount of the composition of 2. It may be present, may be 70 to 100% by mass, or may be 90 to 100% by mass.
In the second composition, the content of the hole-transporting material, the hole-injecting material, the electron-transporting material, the electron-injecting material, and the light-emitting material is 100 parts by mass of the crosslinked product of the compound having a crosslinkable group. When used, it is usually 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 crosslinked product of the compound having a crosslinkable group is 100 parts by mass.

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

The second ink may further contain at least one selected from the group consisting of hole-transporting materials, hole-injecting materials, electron-transporting materials, electron-injecting materials, light-emitting materials, and antioxidants.
The second ink may contain one of each of the hole transport material, the hole injection material, the electron transport material, the electron injection material, the luminescent material, and the antioxidant, or may contain two or more of them. may have been
Examples and preferred ranges of the hole-transporting material, the electron-transporting material, the hole-injecting material, the electron-injecting material, the light-emitting material, and the antioxidant, which the second ink may further include, are described in the second composition, respectively. are the same as the examples and preferred ranges of the hole transport material, electron transport material, hole injection material, electron injection material, light emitting material and antioxidant contained in .
The 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 contain, is the content of the compound having a cross-linking group, which is 100 mass When expressed as parts, 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 having a cross-linking group is 100 parts by mass.

<Light emitting element>
A light-emitting device of the present disclosure is a light-emitting device having an anode, a cathode, and first and second layers provided between the anode and the cathode.
The light-emitting device of 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 excellent luminance lifetime.
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 a crosslinked compound having a crosslinkable group, so that the light emitting properties, charge transport properties and/or charge injection properties of the second layer can be improved or adjusted. Furthermore, since the light-emitting element of the present disclosure has the second layer, the charge injection property from the anode or the cathode to the first layer is improved or adjusted, and the luminance life of the light-emitting element of the present disclosure is extended. It is presumed that it will be an excellent light-emitting device.

From the above point of view, the first layer and the second layer are preferably adjacent to each other because the luminance lifetime of the light emitting element is superior.

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

In the light-emitting device of the present disclosure, the second layer is preferably a layer provided between the anode and the first layer because the light-emitting device of the present disclosure has a superior luminance lifetime. It is more preferably a hole injection layer, a hole transport layer or a second light-emitting layer provided between the layers, and a hole injection layer or hole transport layer provided between the anode and the first layer. is more preferred, and a hole transport layer provided between the anode and the first layer is particularly preferred.

In the light-emitting device of the present disclosure, when the second layer is the second light-emitting layer provided between the anode and the first layer, the luminance lifetime of the light-emitting device of the present disclosure is superior. It is preferable to further have at least one layer of a hole injection layer and a hole transport layer between the layers of . In addition, when the second layer is a second light-emitting layer provided between the anode and the first layer, the luminance life of the light-emitting element of the present disclosure is better, so Furthermore, it is preferable to further have at least one layer of an electron injection layer and an electron transport layer.
In the light-emitting device of the present disclosure, when the second layer is a hole-transporting layer provided between the anode and the first layer, the luminance lifetime of the light-emitting device of the present disclosure is superior. It is preferable to further have a hole injection layer between the layers. Further, when the second layer is a hole-transporting layer provided between the anode and the first layer, the luminance life of the light-emitting device of the present disclosure is better, so , an electron injection layer and an electron transport layer.
In the light emitting device of the present disclosure, when the second layer is a hole injection layer provided between the anode and the first layer, the luminance lifetime of the light emitting device of the present disclosure is superior. It is preferable to further have a hole transport layer between the second layer. In addition, when the second layer is a hole injection layer provided between the anode and the first layer, the luminance lifetime of the light-emitting device of the present disclosure is better, so , an electron injection layer and an electron transport layer.
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 luminance lifetime of the light-emitting device of the present disclosure is better, so the anode and the first layer It is preferable to further have at least one layer of a hole injection layer and a hole transport layer between. In addition, when the second layer is an electron-transporting layer provided between the cathode and the first layer, the luminance lifetime of the light-emitting device of the present disclosure is better. Therefore, between the cathode and the second layer, It is preferable to further have an electron injection 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/hole-transport layer (second layer)/first light-emitting layer (first layer)/cathode (D2) anode/hole-injection layer/hole-transport layer (second layer)/ First light emitting layer (first layer)/cathode (D3) anode/hole injection layer/hole transport layer (second layer)/first light emitting layer (first layer)/electron transport layer/ Cathode (D4) anode/hole injection layer/hole transport layer (second layer)/first emitting layer (first layer)/electron injection layer/cathode (D5) anode/hole injection layer/positive hole-transporting layer (second layer)/first light-emitting layer (first layer)/electron-transporting layer/electron-injecting layer/cathode (D6) anode/hole-injecting layer/hole-transporting layer (second layer) )/first emitting layer (first layer)/second emitting layer/electron transport layer/electron injection layer/cathode (D7) anode/hole injection layer/hole transport layer (second layer)/ Second light-emitting layer/first light-emitting layer (first layer)/electron transport layer/electron injection layer/cathode (D8) anode/second light-emitting layer (second layer)/first light-emitting layer ( first layer)/cathode (D9) anode/hole injection layer/second light-emitting layer (second layer)/first light-emitting layer (first layer)/electron transport layer/cathode (D10) anode /hole injection layer/second light emitting layer (second layer)/first light emitting layer (first layer)/electron injection layer/cathode (D11) anode/hole injection layer/second light emitting layer (Second layer)/first light emitting layer (first layer)/electron transport layer/electron injection layer/cathode (D12) anode/hole injection layer/hole transport layer/second light emitting layer (second 2 layer)/first light emitting layer (first layer)/electron transport layer/electron injection layer/cathode (D13) anode/hole injection layer/hole transport layer/first light emitting layer (first layer)/second light emitting layer (second layer)/electron transport layer/electron injection layer/cathode (D14) anode/hole injection layer/hole transport layer/first light emitting layer (first layer) /electron transport layer (second layer)/electron injection layer/cathode (D15) anode/hole injection layer (second layer)/first light emitting layer (first layer)/cathode (D16) anode/ Hole injection layer (second layer)/first emitting layer (first layer)/electron transport layer/electron injection layer/cathode (D17) anode/hole injection layer (second layer)/holes Transport layer/first light emitting layer (first layer)/electron transport layer/electron injection layer/cathode

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

In the light emitting device of 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 the layers to be stacked may be adjusted in consideration of the luminance lifetime of the light-emitting element.

[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.
If the light-emitting device of the present disclosure has a second light-emitting layer, and the hole-injection layer described below, the hole-transport layer described later, and the electron-transport layer described later are not the second layer, then the second light-emitting layer is preferably the second layer.

[Hole transport layer]
The hole-transporting layer is the second layer or a layer containing a hole-transporting material, preferably the second layer. When the hole-transporting layer is a layer containing a hole-transporting material, the hole-transporting material includes, for example, the hole-transporting material that the 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.
When the light-emitting device of the present disclosure has a hole-transport layer, and the hole-injection layer described below, the second light-emitting layer described above, and the electron-transport layer described below are not the second layer, the hole-transport layer is It is preferably the second layer.

[Electron transport layer]
The electron-transporting layer is a second layer or a layer containing an electron-transporting material, preferably a layer containing an electron-transporting material. When the electron-transporting layer is a layer containing an electron-transporting material, the electron-transporting material contained in the electron-transporting layer includes, for example, the electron-transporting material that the 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 hole-injecting layer described below, the second light-emitting layer described above, and the hole-transporting layer described above are not the second layer, the electron-transporting layer is the second layer. Two layers are preferred.

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

[Electron injection layer]
An electron injection layer is a layer containing an electron injection material. The electron injection material contained in the electron injection layer includes, for example, the electron injection material that the 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.

[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 the present disclosure, at least one of the anode and 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 lamination 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 disclosure, 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 first layer. It may be formed by the wet method described in the section of the first ink using the ink containing the solvent described in the section of the ink, or may be formed by the dry method such as the 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 production of the light emitting device of the present disclosure. 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 the present disclosure. That is, the second layer is preferably formed by a wet method using the second ink.

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

From the above viewpoint, in the method for manufacturing a light-emitting device of the present disclosure, manufacturing of the light-emitting device of the present disclosure is facilitated. It is preferable to include a step of cross-linking the compound having a cross-linking group contained in the layer to form a second layer containing a cross-linked compound of the compound having a cross-linking group.
In the step of forming the second layer, the method of cross-linking the compound having a cross-linking group is preferably a method of cross-linking by heating or light irradiation because it facilitates the production of the light-emitting device of the present disclosure. method is more preferred.

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

As the step of forming the second layer, for example, after forming the layer by a wet method using the second ink, the compound having a cross-linking group contained in the layer is cross-linked to form the second layer. method of forming.

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

The light-emitting device of 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 is 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).

Calculation of the _ΔEST value of the compound was performed as follows.
First, 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 compound H1, metal complex MC1, metal complex MC2 and compound B1>
Compound H1 and compound B1 were manufactured by Luminescence Technology.
Metal complex MC1 and metal complex MC2 were synthesized according to the method described in JP-A-2013-147551.

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 M9>
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 JP-A-2010-189630.
Compound M5 was synthesized according to the method described in JP-A-2011-174062.
Compound M6 was synthesized according to the method described in WO2002/045184.
Compound M7 was synthesized according to the method described in JP-A-2010-215886.
Compound M8 was synthesized according to the method described in JP-A-2008-106241.
Compound M9 was synthesized according to the method described in WO2015/141603.

<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 HTL-2>
Polymer compound HTL-2 was synthesized using compound M5, compound M3, compound M6 and compound M7 according to the method described in JP-A-2012-144722. The polymer compound HTL-2 had an Mn of 5.0×10 ⁴ and an Mw of 2.5×10 ⁵ .
The theoretical values obtained from the amounts of the raw materials for the polymer compound HTL-2 are the structural units derived from the compound M5, the structural units derived from the compound M3, the structural units derived from the compound M6, and the structural units derived from the compound A copolymer composed of structural units derived from M7 in a molar ratio of 50:30:12.5:7.5.

<Synthesis of polymer compound HTL-3>
Polymer compound HTL-3 was synthesized using compound M5, compound M3, compound M6 and compound M8 according to the method described in JP-A-2012-144722. The Mn of the polymer compound HTL-3 was 7.8×10 ⁴ and the Mw was 2.6×10 ⁵ .
The theoretical values obtained from the amounts of the raw materials for the polymer compound HTL-3 are the structural units derived from the compound M5, the structural units derived from the compound M3, the structural units derived from the compound M6, and the structural units derived from the compound A copolymer composed of structural units derived from M8 in a molar ratio of 50:30:12.5:7.5.

<Acquisition of low-molecular-weight compound HTL-4>
Low-molecular-weight compound HTL-4 manufactured by Luminescence Technology was used.

<Synthesis of polymer compound HTL-5>
Polymer compound HTL-5 was synthesized using compound M4 and compound M3 according to the method described in WO2019/004247. The polymer compound HTL-5 had an Mn of 4.5×10 ⁴ and an Mw of 1.5×10 ⁵ .
In the polymer compound HTL-5, the theoretical value obtained from the amount of the raw material charged was such that the structural units derived from the compound M4 and the structural units derived from the compound M3 were formed at a molar ratio of 50:50. It is a copolymer. Note that the polymer compound HTL-5 is a polymer compound having no cross-linking group.

<Synthesis of polymer compound HTL-6>
Polymer compound HTL-6 was synthesized using compound M5, compound M9, compound M6 and compound M8 according to the method described in WO2015/141603. The Mn of the polymer compound HTL-6 was 6.6×10 ⁴ and the Mw was 2.3×10 ⁵ .
The theoretical values obtained from the amounts of the raw materials for the polymer compound HTL-6 are the structural units derived from the compound M5, the structural units derived from the compound M9, the structural units derived from the compound M6, and the structural units derived from the compound A copolymer composed of structural units derived from M8 in a molar ratio of 50:30:12.5:7.5.

<Synthesis of polymer compound HTL-7>
Polymer compound HTL-7 was synthesized using compound M4, compound M3 and compound M8 according to the method described in WO2019/004247. The Mn of the polymer compound HTL-7 was 2.6×10 ⁴ and the Mw was 1.4×10 ⁵ .
In the polymer compound HTL-7, the theoretical value obtained from the amount of the raw material charged is that the structural unit derived from the compound M4, the structural unit derived from the compound M3, and the structural unit derived from the compound M8 are It is a copolymer composed of a molar ratio of 50:42.5:7.5.

<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.

<Example D1> Production and Evaluation of Light-Emitting Element 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 second 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. 2 layers (hole transport layers) were formed. By this heating, the polymer compound HTL-1 was in a crosslinked state.

(Formation of first layer)
Compound H1, metal complex MC1 and compound B1 (compound H1/metal complex 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 second layer by spin coating, and the first layer ( light-emitting layer) was formed.

(Formation of electron transport 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 light-emitting layer by spin coating. An electron transport layer was formed by heating at 130° C. for 10 minutes in a gas atmosphere.

(Formation of cathode)
After reducing the pressure of the substrate on which the electron transport 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 electron transport layer as a cathode, and then the sodium fluoride layer was deposited. About 80 nm of aluminum was evaporated on top. After vapor deposition, the substrate on which the cathode was formed was sealed with a glass substrate to produce a light-emitting device D1.

(Evaluation of Light Emitting Element)
EL light emission was observed by applying a voltage to the light emitting element D1. The chromaticity coordinates (x, y) at 300 cd/m ² were (0.14, 0.13). After setting the current value so that the initial luminance was 300 cd/m ² , the device was driven at a constant current, and the time until the luminance reached 60% of the initial luminance (hereinafter also referred to as LT60) was measured.

<Example D2> Production and Evaluation of Light Emitting Device D2 Except for using "polymer compound HTL-2" instead of "polymer compound HTL-1" in Example D1 (formation of the second layer). A light-emitting device D2 was produced in the same manner as in Example D1. In addition, in Example D2 (formation of the second layer), the polymer compound HTL-2 was in a crosslinked state by heating.
EL light emission was observed by applying a voltage to the light emitting element D2. The chromaticity coordinates (x, y) at 300 cd/m ² were (0.14, 0.13). After setting the current value so that the initial luminance was 300 cd/m ² , the device was driven at a constant current, and LT60 was measured.

<Example D3> Production and Evaluation of Light Emitting Device D3 Except for using “polymer compound HTL-3” in place of “polymer compound HTL-1” in Example D1 (formation of the second layer). A light-emitting device D3 was produced in the same manner as in Example D1. In addition, in Example D3 (formation of the second layer), the polymer compound HTL-3 was in a crosslinked state by heating.
EL light emission was observed by applying a voltage to the light emitting element D3. The chromaticity coordinates (x, y) at 300 cd/m ² were (0.14, 0.14). After setting the current value so that the initial luminance was 300 cd/m ² , the device was driven at a constant current, and LT60 was measured.

<Example D4> Production and Evaluation of Light-Emitting Device D4 Except for using “low-molecular-weight compound HTL-4” in place of “polymeric compound HTL-1” in (formation of second layer) of Example D1. A light-emitting device D4 was produced in the same manner as in Example D1. In addition, in Example D4 (formation of the second layer), the low-molecular-weight compound HTL-4 was in a crosslinked state by heating.
EL light emission was observed by applying a voltage to the light emitting element D4. The chromaticity coordinates (x, y) at 300 cd/m ² were (0.15, 0.15). After setting the current value so that the initial luminance was 300 cd/m ² , the device was driven at a constant current, and LT60 was measured.

<Comparative Example CD1> Production and Evaluation of Light-Emitting Device CD1 Except for using “Polymer Compound HTL-5” instead of “Polymer Compound HTL-1” in Example D1 (Formation of Second Layer) A light-emitting device CD1 was fabricated in the same manner as in Example D1.
EL light emission was observed by applying a voltage to the light emitting element CD1. The chromaticity coordinates (x, y) at 300 cd/m ² were (0.15, 0.13). After setting the current value so that the initial luminance was 300 cd/m ² , the device was driven at a constant current, and LT60 was measured.

Table 5 shows the results of Examples D1 to D4 and Comparative Example CD1. "LT60 (relative value)" in Table 5 is LT6 of light-emitting elements D1 to D4 when LT60 of light-emitting element CD1 is 1.00.
A relative value of 0 (that is, a value obtained by dividing the LT60 of the light emitting elements D1 to D4 by the LT60 of the light emitting element CD1).

<Example D5> Production and Evaluation of Light-Emitting Element D5 (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 second 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. 2 layers (hole transport layers) were formed. By this heating, the polymer compound HTL-1 was in a crosslinked state.

(Formation of first layer)
Compound H1, metal complex MC2 and compound B1 (compound H1/metal complex MC2/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 second layer by spin coating, and the first layer ( light-emitting layer) was formed.

(Formation of electron transport 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. and an 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 electron transport 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 electron transport layer as a cathode, and then the sodium fluoride layer was deposited. About 80 nm of aluminum was evaporated on top. After vapor deposition, the substrate on which the cathode was formed was sealed with a glass substrate to produce a light-emitting device D5.

(Evaluation of Light Emitting Element)
EL light emission was observed by applying a voltage to the light emitting element D5. The chromaticity coordinates (x, y) at 300 cd/m ² were (0.15, 0.25). After setting the current value so that the initial luminance was 300 cd/m ² , the device was driven at a constant current, and the time until the luminance reached 60% of the initial luminance (hereinafter also referred to as LT60) was measured.

<Example D6> Production and Evaluation of Light Emitting Device D6 Except for using “polymer compound HTL-2” in place of “polymer compound HTL-1” in (formation of second layer) of Example D5. A light-emitting device D6 was produced in the same manner as in Example D5. In addition, in Example D6 (formation of the second layer), the polymer compound HTL-2 was in a crosslinked state by heating.
EL light emission was observed by applying a voltage to the light emitting element D6. The chromaticity coordinates (x, y) at 300 cd/m ² were (0.15, 0.23). After setting the current value so that the initial luminance was 300 cd/m ² , the device was driven at a constant current, and LT60 was measured.

<Example D7> Production and Evaluation of Light-Emitting Device D7 Except for using "polymer compound HTL-3" instead of "polymer compound HTL-1" in Example D5 (formation of the second layer). A light-emitting device D7 was produced in the same manner as in Example D5. In addition, in Example D7 (formation of the second layer), the polymer compound HTL-3 was in a crosslinked state by heating.
EL light emission was observed by applying a voltage to the light emitting element D7. The chromaticity coordinates (x, y) at 300 cd/m ² were (0.15, 0.23). After setting the current value so that the initial luminance was 300 cd/m ² , the device was driven at a constant current, and LT60 was measured.

<Example D8> Production and Evaluation of Light Emitting Device D8 Performed except that "Compound HTL-4" was used instead of "Polymer Compound HTL-1" in Example D5 (formation of second layer). A light-emitting device D8 was produced in the same manner as in Example D5. In addition, in Example D8 (formation of the second layer), the compound HTL-4 was in a crosslinked state by heating.
EL light emission was observed by applying a voltage to the light emitting element D8. The chromaticity coordinates (x, y) at 300 cd/m ² were (0.16, 0.26). After setting the current value so that the initial luminance was 300 cd/m ² , the device was driven at a constant current, and LT60 was measured.

<Example D9> Production and evaluation of light-emitting device D9 Except for using "polymer compound HTL-6" in place of "polymer compound HTL-1" in Example D5 (formation of second layer) A light-emitting device D9 was produced in the same manner as in Example D5. In addition, in Example D9 (formation of the second layer), the polymer compound HTL-6 was in a crosslinked state by heating.
EL light emission was observed by applying a voltage to the light emitting element D9. The chromaticity coordinates (x, y) at 300 cd/m ² were (0.16, 0.25). After setting the current value so that the initial luminance was 300 cd/m ² , the device was driven at a constant current, and LT60 was measured.

<Example D10> Production and evaluation of light-emitting device D10 Except for using "polymer compound HTL-7" instead of "polymer compound HTL-1" in Example D5 (formation of second layer) A light-emitting device D10 was produced in the same manner as in Example D5. In addition, in (formation of the second layer) of Example D10, the polymer compound HTL-7 was in a crosslinked state by heating.
EL emission was observed by applying a voltage to the light emitting element D10. The chromaticity coordinates (x, y) at 300 cd/m ² were (0.15, 0.22). After setting the current value so that the initial luminance was 300 cd/m ² , the device was driven at a constant current, and LT60 was measured.

<Comparative Example CD2> Production and Evaluation of Light-Emitting Device CD2 Except for using “Polymer Compound HTL-5” instead of “Polymer Compound HTL-1” in Example D5 (Formation of Second Layer) A light-emitting element CD2 was fabricated in the same manner as in Example D5.
EL light emission was observed by applying a voltage to the light emitting element CD2. The chromaticity coordinates (x, y) at 300 cd/m ² were (0.15, 0.23). After setting the current value so that the initial luminance was 300 cd/m ² , the device was driven at a constant current, and LT60 was measured.

Table 6 shows the results of Examples D5 to D10 and Comparative Example CD2. "LT60 (relative value)" in Table 6 is the relative value of the LT60 of the light emitting elements D5 to D10 when the LT60 of the light emitting element CD2 is 1.00 (that is, the LT60 of the light emitting elements D5 to D10 is CD2 divided by LT60).

Light-emitting elements D1 to D4 and light-emitting elements D5 to D10, in which the second layer is a layer containing a crosslinked compound of a compound having a crosslinkable group, are layers in which the second layer does not contain a crosslinked compound of a compound having a crosslinkable group. It can be seen that the light-emitting element is superior in luminance lifetime as compared with the light-emitting element CD1 and the light-emitting element CD2.

Claims (17)

A light-emitting device having an anode, a cathode, and first and second layers provided between the anode and the cathode,
The first layer is
selected from the group consisting of a metal complex represented by formula (1) and a polymer compound (A) containing a structural unit having a group obtained by removing one or more hydrogen atoms from the metal complex represented by formula (1) and at least one
A low-molecular-weight compound (B) having 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 polymer 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 containing
The light-emitting device, wherein the second layer is a layer containing a crosslinked compound having a crosslinkable group.

[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 heterocyclic ring containing a 5-membered ring, 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 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, and these rings have a substituent The light-emitting device according to claim 1, wherein the light-emitting device may be The ring L ¹ is a diazole ring or 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 3. The light-emitting device according to claim 1, wherein may have a substituent. 2. The light-emitting device according to claim 1, wherein said 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. 5. The light-emitting device according to claim 4, 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). The light-emitting device according to .

[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. ] 7. The light-emitting device according to claim 6, 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)-. 8. The light-emitting device according to claim 7, wherein said Y ¹ , said Y ² and said Y ³ are groups represented by -N(Ry)-. 2. The light-emitting device according to claim 1, wherein said compound having a cross-linking group is a polymer compound containing a structural unit having said cross-linking group. 10. The light-emitting device according to claim 9, wherein the structural unit having the cross-linking group is a structural unit represented by formula (Z) or a structural unit represented by formula (Z').

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

[In the formula,
mA, m and c each independently represent an integer of 0 or more. When multiple mA are present, they may be the same or different. When there are multiple m's, they may be the same or different.
Ar ⁵ represents a hydrocarbon group, a heterocyclic group, or a group in which at least one hydrocarbon group and at least one heterocyclic group are directly bonded, and these groups may have a substituent good. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. When multiple Ar ⁵ are present, they may be the same or different.
Ar ⁴ and Ar ⁶ each independently represent an arylene group or a divalent heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded.
K ^A represents an alkylene group, a cycloalkylene group, an arylene group, a divalent heterocyclic group, a group represented by -N(R'')-, an oxygen atom or a sulfur atom, and these groups are substituents. may have. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. R'' represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. When multiple K ^A are present, they may be the same or different.
X' represents a hydrogen atom, a bridging group, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. When multiple X' are present, they may be the same or different. However, at least one X' is a bridging group. ] The polymer compound containing a structural unit having a cross-linking group further contains at least one structural unit selected from the group consisting of structural units represented by formula (X) and structural units represented by formula (Y). 11. The light-emitting device according to claim 9 or 10.

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

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

[In the formula,
m ^B1 , m ^B2 and m ^B3 each independently represent an integer of 0 or more. A plurality of m ^B1 may be the same or different. When multiple ^mB3 are present, they may be the same or different.
Ar ⁷ represents a hydrocarbon group, a heterocyclic group, or a group in which at least one hydrocarbon group and at least one heterocyclic group are directly bonded, and these groups may have a substituent good. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. When multiple Ar ⁷ are present, they may be the same or different.
L ^B1 represents an alkylene group, a cycloalkylene group, an arylene group, a divalent heterocyclic group, a group represented by -N(R''')-, an oxygen atom or a sulfur atom, and these groups are substituents may have When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. R''' represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. When multiple L ^B1 are present, they may be the same or different. X'' is
It represents a bridging group, a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, and these groups may have a substituent. When there are multiple such substituents, they may be the same or different, and may be bonded to each other to form a ring together with the atoms to which they are bonded. Multiple X'' may be the same or different. However, at least one of the plurality of X'' is a cross-linking group. ] 13. The light-emitting device according to claim 1, 2, 4, 6, 9, or 12, wherein the cross-linking group is at least one cross-linking group selected from Group A of cross-linking groups.
(Crosslinking group A group)

[In the formula, R ^XL represents a methylene group, an oxygen atom or a sulfur atom, and n ^XL represents an integer of 0 to 5. When multiple R ^XL are present, they may be the same or different. When multiple ^nXL are present, they may be the same or different. *1 represents the binding position. These bridging groups may have substituents, and when there are multiple substituents, they may be the same or different, and are bonded to each other to form a ring together with the atoms to which they are bonded. may ] 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) Claim 1, Claim 2, Claim 4, Claim 6, Claim 9, or Claim 12, further comprising at least one selected from the group consisting of polymer compounds containing one kind of constitutional unit. light-emitting element.

[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. ] Claim 1, wherein the first layer further contains at least one selected from the group consisting of a hole-transporting material, a hole-injecting material, an electron-transporting material, an electron-injecting material, a light-emitting material, and an antioxidant. 13. The light-emitting device according to claim 2, 4, 6, 9 or 12. 2. The light-emitting device according to claim 1, wherein said first layer and said second layer are adjacent. 17. The light-emitting device according to claim 1, wherein said second layer is a layer provided between said anode and said first layer.