阅读说明：本技术 发光元件和发光元件用组合物 (Light-emitting element and composition for light-emitting element ) 是由 佐佐田敏明 松本龙二 于 2020-03-16 设计创作，主要内容包括：提供在外部量子效率优异的发光元件的制造中有用的组合物以及提供含有该组合物的发光元件。一种发光元件,其具备阳极、阴极和设置于阳极和阴极之间的包含发光元件用组合物的有机层,发光元件用组合物含有：选自式(FH)所示的化合物和包含具有从式(FH)所示的化合物去除1个以上氢原子而成的基团的结构单元的高分子化合物中的至少2种化合物(A)、和具有在环内包含硼原子和氮原子的稠合杂环骨架(b)的化合物(B)。(Provided are a composition useful for producing a light-emitting element having excellent external quantum efficiency, and a light-emitting element containing the composition. A light-emitting element comprising an anode, a cathode, and an organic layer containing a composition for light-emitting elements, the composition for light-emitting elements comprising: at least 2 compounds (A) selected from the group consisting of compounds represented by Formula (FH) and polymer compounds containing a structural unit having a group obtained by removing 1 or more hydrogen atoms from the compounds represented by Formula (FH), and a condensed heterocyclic skeleton (b) having a boron atom and a nitrogen atom in the ringA compound (B).)

1. A light-emitting element is provided with:

an anode,

A cathode, and

an organic layer containing a composition for a light-emitting element disposed between the anode and the cathode,

the composition for a light-emitting element contains

At least 2 compounds A selected from the group consisting of compounds represented by Formula (FH) and polymer compounds containing a structural unit having a group obtained by removing 1 or more hydrogen atoms from the compounds represented by Formula (FH), and

a compound B having a condensed heterocyclic skeleton B containing a boron atom and a nitrogen atom in the ring,

in the formula (I), the compound is shown in the specification,

n^1Hrepresents an integer of 0 or more and is,

Ar^1Hdenotes the removal of a hydrogen atom n directly bonded to a ring-constituting atom from a heterocyclic compound containing a nitrogen atom in the ring^1HA plurality of groups each of which optionally has a substituent, and when a plurality of the substituents are present, they are optionally the same or different and are optionally bonded to each other to form a ring together with the atom to which each of the substituents is bonded, wherein the heterocyclic compound is a heterocyclic compound not containing the fused heterocyclic skeleton b,

R^1Hrepresents an aryl group, a monovalent heterocyclic group or a substituted amino group, which groups optionally have a substituent which is optionally the same or different in the case where plural, and which is optionally bonded to each other to form a ring together with the atom to which each is bonded, R^1HIn the case where a plurality of them are present, they may be the same or different, and may be bonded to each other to form a ring together with the atom to which each is bonded, wherein the monovalent heterocyclic group is a group obtained by removing 1 hydrogen atom directly bonded to a ring-constituting atom from a heterocyclic compound not containing the fused heterocyclic skeleton b, the group optionally having a substituent,

Ar^1Hoptionally having substituents and R^1HOptionally bonded to each other to eachThe bonded atoms together form a ring.

2. The light-emitting element according to claim 1,

at least 1 of the polymer compounds is contained as the compound A.

3. The light-emitting element according to claim 1 or 2,

ar is^1HThe heterocyclic compound in (b) is a monocyclic heterocyclic compound containing a nitrogen atom in the ring, a bicyclic heterocyclic compound containing a nitrogen atom in the ring, or a tricyclic heterocyclic compound containing a nitrogen atom in the ring.

4. The light-emitting element according to claim 3,

ar is^1HThe heterocyclic compound of (a) is oxadiazole, thiadiazole, pyrrole, oxadiazole, triazole, pyridine, diazabenzene, triazine, azanaphthalene, naphthyridine, indole, benzodiazole, carbazole, azacarbazole, diazacarbazole, phenoxazine, phenothiazine, 9, 10-dihydroacridine, 5, 10-dihydrophenazine, azaanthracene, diazaanthracene, azaphenanthrene or phenanthroline.

5. The light-emitting element according to any one of claims 1 to 4,

the compound B is a compound shown as a formula (1-1), a compound shown as a formula (1-2) or a compound shown as a formula (1-3),

in the formula (I), the compound is shown in the specification,

Ar¹、Ar²and Ar³Each independently represents an aromatic hydrocarbon group or a heterocyclic group, which may have a substituent, and when a plurality of such substituents are present, they may be the same or different, and may be bonded to each other to form a single bond with the atom to which each is bondedThe shape of the ring is such that,

Y¹represents a group represented by-N (Ry) -or a salt thereof,

Y²and Y³Each independently represents a single bond, an oxygen atom, a sulfur atom, a selenium atom, -N (Ry) -representing a group, an alkylene group or a cycloalkylene group, which groups optionally have a substituent, which is optionally the same or different in the presence of plural, optionally bonded to each other to form a ring together with each bonded atom, Ry represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, which groups optionally have a substituent, which is optionally the same or different in the presence of plural, optionally bonded to each other to form a ring together with each bonded atom, Ry is optionally the same or different in the presence of plural, Ry optionally directly or via a linking group and Ar¹、Ar²Or Ar³And (4) bonding.

6. The light-emitting element according to claim 5,

said Y is²And said Y³Is a group represented by-N (Ry) -or a pharmaceutically acceptable salt thereof.

7. The light-emitting element according to any one of claims 1 to 6,

the composition for a light-emitting element further contains at least 1 selected from a hole-transporting material, a hole-injecting material, an electron-transporting material, an electron-injecting material, a light-emitting material, an antioxidant, and a solvent.

8. A composition for a light-emitting element, comprising:

at least 2 compounds A selected from the group consisting of compounds represented by Formula (FH) and polymer compounds containing a structural unit having a group obtained by removing 1 or more hydrogen atoms from the compounds represented by Formula (FH), and

a compound B having a condensed heterocyclic skeleton B containing a boron atom and a nitrogen atom in the ring,

in the formula (I), the compound is shown in the specification,

n^1Hrepresents an integer of 0 or more and is,

Ar^1Hdenotes the removal of a hydrogen atom n directly bonded to a ring-constituting atom from a heterocyclic compound containing a nitrogen atom in the ring^1HA plurality of groups each of which optionally has a substituent, and when a plurality of the substituents are present, they are optionally the same or different and are optionally bonded to each other to form a ring together with the atom to which each of the substituents is bonded, wherein the heterocyclic compound is a heterocyclic compound not containing the fused heterocyclic skeleton b,

R^1Hrepresents an aryl group, a monovalent heterocyclic group or a substituted amino group, which groups optionally have a substituent which is optionally the same or different in the case where plural, and which is optionally bonded to each other to form a ring together with the atom to which each is bonded, R^1HIn the case where a plurality of them are present, they may be the same or different, and may be bonded to each other to form a ring together with the atom to which each is bonded, wherein the monovalent heterocyclic group is a group obtained by removing 1 hydrogen atom directly bonded to a ring-constituting atom from a heterocyclic compound not containing the fused heterocyclic skeleton b, the group optionally having a substituent,

Ar^1Hoptionally having substituents and R^1HOptionally bonded to each other to form a ring together with the respective bonded atoms.

9. The composition for a light-emitting element according to claim 8,

at least 1 of the polymer compounds is contained as the compound A.

10. The composition for a light-emitting element according to claim 8 or 9,

ar is^1HThe heterocyclic compound in (1) is a monocyclic heterocyclic compound containing a nitrogen atom in the ring, or a bicyclic heterocyclic compound containing a nitrogen atom in the ringOr tricyclic heterocyclic compounds containing a nitrogen atom within the ring.

11. The composition for a light-emitting element according to any one of claims 8 to 10,

the compound B is a compound shown as a formula (1-1), a compound shown as a formula (1-2) or a compound shown as a formula (1-3),

in the formula (I), the compound is shown in the specification,

Ar¹、Ar²and Ar³Each independently represents an aromatic hydrocarbon group or a heterocyclic group, which optionally has a substituent, and when a plurality of such substituents are present, they are optionally the same or different, and are optionally bonded to each other to form a ring together with the atom to which each is bonded,

Y¹represents a group represented by-N (Ry) -or a salt thereof,

Y²and Y³Each independently represents a single bond, an oxygen atom, a sulfur atom, a selenium atom, -N (Ry) -representing a group, an alkylene group or a cycloalkylene group, which groups optionally have a substituent, which is optionally the same or different in the presence of plural, optionally bonded to each other to form a ring together with each bonded atom, Ry represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, which groups optionally have a substituent, which is optionally the same or different in the presence of plural, optionally bonded to each other to form a ring together with each bonded atom, Ry is optionally the same or different in the presence of plural, Ry optionally directly or via a linking group and Ar¹、Ar²Or Ar³And (4) bonding.

12. The composition for a light-emitting element according to claim 11,

said Y is²And said Y³Is a group represented by-N (Ry) -or a pharmaceutically acceptable salt thereof.

13. The composition for a light-emitting element according to any one of claims 8 to 12, wherein,

further contains at least 1 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, an antioxidant and a solvent.

Technical Field

The present invention relates to a light-emitting element and a composition for a light-emitting element.

Background

Light-emitting elements such as organic electroluminescent elements can be suitably used for displays and lighting, for example. As a light-emitting material used for a light-emitting layer of a light-emitting element, for example, patent document 1 proposes a composition containing a compound G1.

[ chemical formula 1]

Documents of the prior art

Patent document

Patent document 1: international publication No. 2018/062278

Disclosure of Invention

Problems to be solved by the invention

However, the light-emitting element manufactured using the above composition is not necessarily sufficient in external quantum efficiency.

Accordingly, an object of the present invention is to provide a composition useful for producing a light-emitting element having excellent external quantum efficiency, and to provide a light-emitting element containing the composition.

Means for solving the problems

The present inventors have conducted extensive studies to solve the above problems, and as a result, have found that a light-emitting element having excellent external quantum efficiency is formed by using a composition for a light-emitting element containing 2 or more specific compounds (a) and (B), and have completed the present invention.

Namely, the present invention provides the following [1] to [13 ].

[1] A light-emitting element is provided with:

an anode,

A cathode, and

an organic layer disposed between the anode and the cathode and containing a composition for a light-emitting element, the composition for a light-emitting element containing

At least 2 compounds (A) selected from the group consisting of compounds represented by Formula (FH) and polymer compounds containing a structural unit having a group obtained by removing 1 or more hydrogen atoms from the compounds represented by Formula (FH), and

a compound (B) having a condensed heterocyclic skeleton (B) containing a boron atom and a nitrogen atom in the ring.

[ chemical formula 2]

[ in the formula,

n^1Hrepresents an integer of 0 or more.

Ar^1HDenotes the removal of a hydrogen atom n directly bonded to a ring-constituting atom from a heterocyclic compound containing a nitrogen atom in the ring^1HAnd (b) at least one group which may have a substituent. When a plurality of such substituents are present, they may be the same or different, and may be bonded to each other to form a ring together with the atom to which they are bonded. Wherein the heterocyclic compound is a heterocyclic compound not containing the fused heterocyclic skeleton (b).

R^1HRepresents an aryl group, a monovalent heterocyclic group or a substituted amino group, and these groups may have a substituent. When a plurality of such substituents are present, they may be the same or different, and may be bonded to each other to form a ring together with the atom to which they are bonded. R^1HWhen a plurality of atoms are present, 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 monovalent heterocyclic group is a group obtained by removing 1 hydrogen atom directly bonded to an atom constituting a ring from a heterocyclic compound not containing the fused heterocyclic skeleton (b), and the group may have a substituent.

Ar^1HSubstituent which may be present with R^1HMay be bonded to each other to form a ring together with the respective bonded atoms.]

[2] The light-emitting element according to [1], wherein,

contains at least 1 of the above-mentioned polymer compounds as the above-mentioned compound (A).

[3] The light-emitting element according to [1] or [2], wherein,

ar above^1HThe heterocyclic compound in (b) is a monocyclic heterocyclic compound containing a nitrogen atom in the ring, a bicyclic heterocyclic compound containing a nitrogen atom in the ring, or a tricyclic heterocyclic compound containing a nitrogen atom in the ring.

[4] The light-emitting element according to [3], wherein,

ar above^1HThe heterocyclic compound in (b) is oxadiazole, thiadiazole, pyrrole, oxadiazole, triazole, pyridine, diazabenzene, triazine, azanaphthalene, naphthyridine, indole, benzodiazole, carbazole, azacarbazole, diazacarbazole, phenoxazine, phenothiazine, 9, 10-dihydroacridine, 5, 10-dihydrophenazine, azaanthracene, diazaanthracene, azaphenanthrene or phenanthroline.

[5] The light-emitting element according to any one of [1] to [4], wherein,

the compound (B) is a compound represented by the formula (1-1), a compound represented by the formula (1-2) or a compound represented by the formula (1-3).

[ chemical formula 3]

[ in the formula,

Ar¹、Ar²and Ar³Each independently represents an aromatic hydrocarbon group or a heterocyclic group, and these groups may have a substituent. When a plurality of such substituents are present, they may be the same or different, and may be bonded to each other to form a ring together with the atom to which they are bonded.

Y¹Represents a group represented by-N (Ry) -.

Y²And Y³Each independently represents a single bond, 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 a plurality of such substituents are present, they may be the same or different, and may be bonded to each otherThe bonded atoms together form a ring. 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 a plurality of such substituents are present, they may be the same or different, and may be bonded to each other to form a ring together with the atom to which they are bonded. When there are a plurality of Ry, they may be the same or different. Ry may be bonded to Ar directly or via a linking group¹、Ar²Or Ar³And (4) bonding.]

[6] The light-emitting element according to [5], wherein,

y is above²And the above Y³Is a group represented by-N (Ry) -or a pharmaceutically acceptable salt thereof.

[7] The light-emitting element according to any one of [1] to [6],

the composition for a light-emitting element further contains at least 1 selected from a hole-transporting material, a hole-injecting material, an electron-transporting material, an electron-injecting material, a light-emitting material, an antioxidant and a solvent.

[8] A composition for a light-emitting element comprising

At least 2 compounds (A) selected from the group consisting of compounds represented by Formula (FH) and polymer compounds containing a structural unit having a group obtained by removing 1 or more hydrogen atoms from the compounds represented by Formula (FH), and

a compound (B) having a condensed heterocyclic skeleton (B) containing a boron atom and a nitrogen atom in the ring.

[ chemical formula 4]

[ in the formula,

n^1Hrepresents an integer of 0 or more.

Ar^1HDenotes the removal of a hydrogen atom n directly bonded to a ring-constituting atom from a heterocyclic compound containing a nitrogen atom in the ring^1HAnd (b) at least one group which may have a substituent. When a plurality of such substituents are present, they may be the same or different and may beTo form a ring together with the atoms to which they are bonded. Wherein the heterocyclic compound is a heterocyclic compound not containing the fused heterocyclic skeleton (b).

R^1HRepresents an aryl group, a monovalent heterocyclic group or a substituted amino group, and these groups may have a substituent. When a plurality of such substituents are present, they may be the same or different, and may be bonded to each other to form a ring together with the atom to which they are bonded. R^1HWhen a plurality of atoms are present, 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 monovalent heterocyclic group is a group obtained by removing 1 hydrogen atom directly bonded to an atom constituting a ring from a heterocyclic compound not containing the fused heterocyclic skeleton (b), and the group may have a substituent.

Ar^1HSubstituent which may be present with R^1HMay be bonded to each other to form a ring together with the respective bonded atoms.]

[9] The composition for a light-emitting element according to [8], wherein,

contains at least 1 of the above-mentioned polymer compounds as the above-mentioned compound (A).

[10] The composition for a light-emitting element according to [8] or [9], wherein,

ar above^1HThe heterocyclic compound in (b) is a monocyclic heterocyclic compound containing a nitrogen atom in the ring, a bicyclic heterocyclic compound containing a nitrogen atom in the ring, or a tricyclic heterocyclic compound containing a nitrogen atom in the ring.

[11] The composition for a light-emitting element according to any one of [8] to [10], wherein,

the compound (B) is a compound represented by the formula (1-1), a compound represented by the formula (1-2) or a compound represented by the formula (1-3).

[ chemical formula 5]

[ in the formula,

Ar¹、Ar²and Ar³Each independently represents an aromatic hydrocarbon group or a heterocyclic group, and these groups may have a substituent. When a plurality of such substituents are present, they may be the same or different, and may be bonded to each other to form a ring together with the atom to which they are bonded.

Y¹Represents a group represented by-N (Ry) -.

Y²And Y³Each independently represents a single bond, 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 a plurality of such substituents are present, they may be the same or different, and may be bonded to each other to form a ring together with the atom 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 a plurality of such substituents are present, they may be the same or different, and may bond to each other to form a ring together with the atom to which they are bonded, and when a plurality of Ry are present, they may be the same or different. Ry may be bonded to Ar directly or via a linking group¹、Ar²Or Ar³And (4) bonding.]

[12] The composition for a light-emitting element according to [11], wherein,

y is above²And the above Y³Is a group represented by-N (Ry) -or a pharmaceutically acceptable salt thereof.

[13] The composition for a light-emitting element according to any one of [8] to [12], wherein,

further contains at least 1 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, an antioxidant and a solvent.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, a composition useful for manufacturing a light-emitting element having excellent external quantum efficiency can be provided. Further, according to the present invention, a light-emitting element containing the composition can be provided.

Detailed Description

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

Description of common terms

Terms commonly used in the present specification have the following meanings unless otherwise specified.

"Room temperature" means 25 ℃.

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

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

"Low molecular weight compound" means a compound having no molecular weight distribution and a molecular weight of 1X 10⁴The following compounds.

The term "polymer compound" means a compound having a molecular weight distribution and a number average molecular weight of 1X 10 in terms of polystyrene³Above (e.g., 1 × 10)³～1×10⁸) The polymer of (1).

The term "structural unit" means that 1 or more units are present in the polymer compound.

The polymer compound may be any of a block copolymer, a random copolymer, an alternating copolymer, and a graft copolymer, or may be in other forms.

The end groups of the polymer compound are preferably stable groups since the polymerizable groups remain as they are, and when the polymer compound is used for manufacturing a light-emitting element, the light-emitting characteristics or the luminance lifetime may be reduced. The terminal group of the polymer compound is preferably a group conjugated to the main chain, and examples thereof include a group bonded to an aryl group or a monovalent heterocyclic group bonded to the main chain of the polymer compound via a carbon-carbon bond.

The "alkyl group" may be any of a straight chain and a branched chain. The number of carbon atoms of the linear alkyl group excluding the number of carbon atoms of the substituent is usually 1 to 50, preferably 1 to 20, and more preferably 1 to 10. The number of carbon atoms of the branched alkyl group excluding the number of carbon atoms of the substituent is usually 3 to 50, preferably 3 to 20, and more preferably 4 to 10.

The alkyl group may have a substituent. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a 2-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, a 2-ethylbutyl group, a hexyl group, a heptyl group, an octyl group, a 2-ethylhexyl group, a 3-propylheptyl group, a decyl group, a 3, 7-dimethyloctyl group, a 2-ethyloctyl group, a 2-hexyldecyl group and a dodecyl group. The alkyl group may be a group in which some or all of the hydrogen atoms in these groups are substituted with a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, a fluorine atom, or the like. Examples of such an alkyl group include a trifluoromethyl group, a pentafluoroethyl group, a perfluorobutyl group, a perfluorohexyl group, a perfluorooctyl group, a 3-phenylpropyl group, a 3- (4-methylphenyl) propyl group, a 3- (3, 5-dihexylphenyl) propyl group and a 6-ethoxyhexyl group.

The number of carbon atoms of the "cycloalkyl group" is usually 3 to 50, preferably 4 to 10, excluding the number of carbon atoms of the substituent. The cycloalkyl group may have a substituent. Examples of the cycloalkyl group include cyclohexyl and methylcyclohexyl.

The number of carbon atoms of the "alkylene group" is usually 1 to 20, preferably 1 to 15, and more preferably 1 to 10, excluding the number of carbon atoms of the substituent. The alkylene group may have a substituent. Examples of the alkylene group include a methylene group, an ethylene group, a propylene group, a butylene group, a hexylene group and an octylene group.

The number of carbon atoms of the "cycloalkylene group" is usually 3 to 20, preferably 4 to 10, excluding the number of carbon atoms of the substituent. The cycloalkylene group may have a substituent. Examples of the cycloalkylene group include cyclohexylene group.

The "aromatic hydrocarbon group" refers to a group obtained by removing 1 or more hydrogen atoms directly bonded to atoms constituting a ring from an aromatic hydrocarbon. A group obtained by removing 1 hydrogen atom directly bonded to an atom constituting a ring from an aromatic hydrocarbon is also referred to as an "aryl group". A group obtained by removing 2 hydrogen atoms directly bonded to atoms constituting a ring from an aromatic hydrocarbon is also referred to as "arylene".

The number of carbon atoms of the aromatic hydrocarbon group excluding the number of carbon atoms of the substituent is usually 6 to 60, preferably 6 to 40, and more preferably 6 to 20.

Examples of the "aromatic hydrocarbon group" include: the aromatic hydrocarbon group may be a group obtained by removing 1 or more hydrogen atoms directly bonded to atoms constituting a ring from a monocyclic aromatic hydrocarbon (for example, benzene) or polycyclic aromatic hydrocarbon (for example, a bicyclic aromatic hydrocarbon such as naphthalene or indene, a tricyclic aromatic hydrocarbon such as anthracene, phenanthrene, dihydrophenanthrene, or fluorene, a tetracyclic aromatic hydrocarbon such as benzanthracene, triphenylene, benzofluorene, pyrene, or fluoranthene, a pentacyclic aromatic hydrocarbon such as dibenzanthracene, dibenzphenanthrene, dibenzofluorene, perylene, or benzofluoranthene, a hexacyclic aromatic hydrocarbon such as spirobifluorene, or a heptacyclic aromatic hydrocarbon such as benzospirobifluorene or acenaphthofluorene). The aromatic hydrocarbon group includes a group in which a plurality of these groups are bonded. The aromatic hydrocarbon group may have a substituent.

The "alkoxy group" may be any of a straight chain and a branched chain. The number of carbon atoms of the linear alkoxy group is usually 1 to 40, preferably 1 to 10, excluding the number of carbon atoms of the substituent. The number of carbon atoms of the branched alkoxy group excluding the number of carbon atoms of the substituent is usually 3 to 40, preferably 4 to 10.

The alkoxy group may have a substituent. Examples of the alkoxy group include a methoxy group, an ethoxy group, an isopropoxy group, a butoxy group, a hexyloxy group, a 2-ethylhexyloxy group, a 3, 7-dimethyloctyloxy group and a lauryloxy group.

The number of carbon atoms of the "cycloalkoxy group" is usually 3 to 40, preferably 4 to 10, excluding the number of carbon atoms of the substituent. The cycloalkoxy group may have a substituent. Examples of the cycloalkoxy group include a cyclohexyloxy group.

The number of carbon atoms of the "aryloxy group" is usually 6 to 60, preferably 6 to 40, and more preferably 6 to 20, excluding the number of carbon atoms of the substituent. The aryloxy group may have a substituent. Examples of the aryloxy group include a phenoxy group, a naphthoxy group, an anthracenoxy group, and a pyreneoxy group.

The "heterocyclic group" refers to a group obtained by removing 1 or more hydrogen atoms directly bonded to atoms constituting a ring from a heterocyclic compound. Among heterocyclic groups, a "aromatic heterocyclic group" is preferred, which is a group obtained by removing 1 or more hydrogen atoms directly bonded to atoms constituting a ring from an aromatic heterocyclic compound. A group obtained by removing p (p represents an integer of 1 or more) hydrogen atoms 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 the ring-constituting atoms 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 a heterocyclic ring itself such as oxazole, thiophene, furan, pyridine, diazabenzene, triazine, azanaphthalene, naphthyridine and carbazole exhibits aromaticity, and compounds in which an aromatic ring is fused to a heterocyclic ring itself such as phenoxazine, phenothiazine and benzopyran even if the heterocyclic ring itself does not exhibit aromaticity.

The number of carbon atoms of the heterocyclic group excluding the number of carbon atoms of the substituent is usually 1 to 60, preferably 2 to 40, and more preferably 3 to 20. The number of hetero atoms of the aromatic heterocyclic group is usually 1 to 30, preferably 1 to 10, more preferably 1 to 5, and further preferably 1 to 3, excluding the number of hetero atoms of the substituent.

Examples of the heterocyclic group include: from monocyclic heterocyclic compounds (for example, furan, thiophene, oxadiazole, thiadiazole, pyrrole, oxadiazole, triazole, tetrazole, pyridine, diazabenzene and triazine) or polycyclic heterocyclic compounds (for example, bicyclic heterocyclic compounds such as azanaphthalene, naphthyridine, benzofuran, benzothiophene, indole, benzodiazole and benzothiadiazole), dibenzofuran, dibenzothiophene, dibenzoborole, dibenzosilole, dibenzophosphole, dibenzoselenophene, carbazole, azacarbazole, diazacarbazole, phenoxazine, phenothiazine, 9, 10-dihydroacridine, 5, 10-dihydrophenazine, 9-aza-10-boranthracene (Japanese: フェナザボリン), 9-aza-10-phosphahanthrene (phenophosphosphazine), selenphenazine (Phenoselenazine), Tricyclic heterocyclic compounds such as 9-aza-10-silaanthracene (phenoazasine), azaanthracene, diazaanthracene, azaphenanthrene and phenanthroline; tetracyclic heterocyclic compounds such as hexaazatriphenylene, benzocarbazole, benzonaphthofuran, benzonaphthothiophene and the like; pentacyclic heterocyclic compounds such as dibenzocarbazole, indolocarbazole, and indenocarbazole; hexacyclic heterocyclic compounds such as carbazolocarbazole, benzindolocarbazole and benzindenocarbazole; and a heptacyclic heterocyclic compound such as dibenzoindolocarbazole) from which 1 or more hydrogen atoms directly bonded to atoms constituting the ring have been removed. The heterocyclic group includes a group in which a plurality of these groups are bonded. The heterocyclic group may have a substituent.

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

The "amino group" may have a substituent, preferably a substituted amino group (i.e., a secondary or tertiary amino group, more preferably a tertiary amino group). The substituent of the amino group is preferably an alkyl group, a cycloalkyl group, an aryl group, or a monovalent heterocyclic group. When a plurality of substituents are present, the substituents 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 substituent is bonded.

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

Examples of the amino group include a dimethylamino group, a diethylamino group, a diphenylamino group, a bis (methylphenyl) amino group, and a bis (3, 5-di-t-butylphenyl) amino group.

The "alkenyl group" may be any of a straight chain and a branched chain. The number of carbon atoms of the linear alkenyl group excluding the number of carbon atoms of the substituent is usually 2 to 30, preferably 3 to 20. The number of carbon atoms of the branched alkenyl group excluding the number of carbon atoms of the substituent is usually 3 to 30, preferably 4 to 20.

The number of carbon atoms of the "cycloalkenyl group" is usually 3 to 30, preferably 4 to 20, excluding the number of carbon atoms of the substituent.

The alkenyl group and the cycloalkenyl group may have a substituent. Examples of the alkenyl group include a vinyl group, a 1-propenyl group, a 2-butenyl group, a 3-pentenyl group, a 4-pentenyl group, a 1-hexenyl group, a 5-hexenyl group, a 7-octenyl group, and groups in which some or all of the hydrogen atoms in these groups are substituted with a substituent. Examples of the cycloalkenyl group include a cyclohexenyl group, a cyclohexadienyl group, a cyclooctatrienyl group, a norbornenyl group, and groups in which some or all of hydrogen atoms in these groups are substituted with a substituent.

The "alkynyl group" may be any of a straight chain and a branched chain. The number of carbon atoms of the alkynyl group excluding the carbon atoms of the substituent is usually 2 to 20, preferably 3 to 20. The number of carbon atoms of the branched alkynyl group excluding the carbon atoms of the substituent is usually 4 to 30, preferably 4 to 20.

The number of carbon atoms of the "cycloalkynyl group" is usually 4 to 30, preferably 4 to 20, excluding the carbon atoms of the substituent.

The alkynyl group and the cycloalkynyl group may have a substituent. Examples of the alkynyl group include an ethynyl group, a 1-propynyl group, a 2-butynyl group, a 3-pentynyl group, a 4-pentynyl group, a 1-hexynyl group, a 5-hexynyl group, and groups in which some or all of the hydrogen atoms in these groups are substituted with a substituent. Examples of the cycloalkynyl group include cyclooctynyl.

The "crosslinking group" is a group capable of generating a new bond by being subjected to heat, ultraviolet irradiation, near ultraviolet irradiation, visible light irradiation, infrared irradiation, radical reaction, or the like. The crosslinking group is preferably a crosslinking group selected from the group A of crosslinking groups (i.e., a group represented by any one of the formulae (XL-1) to (XL-19)).

(Cross-linking group A group)

[ chemical formula 6]

[ in the formula, R^XLRepresents a methylene group, an oxygen atom or a sulfur atom, n^XLRepresents an integer of 0 to 5. R^XLWhen a plurality of the compounds exist, they may be the same or different. A plurality of n present^XLMay be the same or different. And x 1 represents a bonding site. These crosslinking groups may have a substituent. When a plurality of such substituents are present, they may be the same or different, and may be bonded to each other to form a ring together with the carbon atom to which each substituent is bonded.]

Examples of the "substituent" include a halogen atom, a cyano group, an alkyl group, a cycloalkyl group, an aryl group, a monovalent heterocyclic group, an alkoxy group, a cycloalkoxy group, an aryloxy group, an amino group, a substituted amino group, an alkenyl group, a cycloalkenyl group, an alkynyl group, and a cycloalkynyl group. The substituent may be a crosslinking group. When a plurality of substituents are present, they may be bonded to each other to form a ring together with the atoms to which they are bonded, but preferably do not form a ring.

In the present 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 "Δ E") (the absolute value is referred to as "Δ E")_ST") was calculated by the following method. First, the ground state of the compound was structurally optimized using the density functional method at the B3LYP level. In this case, 6-31 G.ANG.is used as the basis function. Then, using the structure optimized by the obtained structure, the time-dependent density functional method of B3LYP level was used to calculate the Δ E of the compound_ST. When an atom which cannot be used is included in the range of 6 to 31G, LANL2DZ is used for the atom. Note that, as a quantum chemical calculation program, calculation was performed using Gaussian 09.

< composition for light-emitting element >

The composition for a light-emitting element of the present embodiment contains 2 or more compounds (a) and (B).

The composition for a light-emitting element of the present embodiment may contain only 2 kinds of compounds (a), or may contain 3 or more kinds. The composition for a light-emitting element of the present embodiment may contain only 1 kind of compound (B), or may contain 2 or more kinds.

In the composition for a light-emitting element of the present embodiment, the compound (a) is preferably a host material, and the compound (B) is preferably a guest material. In this embodiment, the host material is a material that interacts with the guest material physically, chemically, or electrically. By this interaction, for example, the light-emitting characteristics, the charge transport characteristics, or the charge injection characteristics of the light-emitting element composition of the present embodiment can be improved or adjusted.

In the composition for a light-emitting element of the present embodiment, a light-emitting material is described as an example, and in this case, the host material and the guest material electrically interact with each other to efficiently transmit electric energy from the host material to the guest material, whereby the guest material can be made to emit light more efficiently, and the light-emitting element of the present embodiment is excellent in external quantum efficiency.

When the compound (B) is used as a light-emitting material, the maximum peak wavelength of the emission spectrum of the compound (B) at 25 ℃ is preferably in the visible light region. In this case, the maximum peak wavelength of the emission spectrum of the compound (B) at 25 ℃ is preferably 380nm or more, more preferably 400nm or more, still more preferably 420nm or more, and particularly preferably 440nm or more. The maximum peak wavelength of the emission spectrum of the compound (B) at 25 ℃ is preferably 750nm or less, more preferably 620nm or less, still more preferably 570nm or less, particularly preferably 495nm or less, and particularly preferably 480nm or less.

When the compound (B) is used as a light-emitting material, the half-width of the maximum peak of the emission spectrum at 25 ℃ of the compound (B) is preferably 50nm or less, more preferably 40nm or less, further preferably 30nm or less, and particularly preferably 25nm or less.

The maximum peak wavelength of the emission spectrum at room temperature of the compound can be evaluated as follows: dissolving the compound in organic solvent such as xylene, toluene, chloroform, tetrahydrofuran, etc. to prepare dilute solution (1 × 10)^-6Mass% to 1X 10^-3Mass%), the PL spectrum of the diluted solution was measured at room temperature to evaluate. As the organic solvent for dissolving the compound, xylene is preferable.

In the composition for a light-emitting element of the present embodiment, the content of the compound (B) is usually 0.001 to 99 parts by mass when the total amount of the compound (a) and the compound (B) is 100 parts by mass, but is preferably 0.005 to 70 parts by mass, more preferably 0.01 to 50 parts by mass, further preferably 0.05 to 30 parts by mass, particularly preferably 0.1 to 10 parts by mass, and particularly preferably 0.5 to 5 parts by mass for the reason that the external quantum efficiency of the light-emitting element of the present embodiment is more excellent.

In the composition for a light-emitting element of the present embodiment, the content of at least 1 of the compounds (a) is usually 0.01 to 99 parts by mass when the total amount of the compounds (a) is 100 parts by mass, but is preferably 0.05 to 90 parts by mass, more preferably 0.1 to 70 parts by mass, further preferably 0.5 to 50 parts by mass, particularly preferably 1 to 30 parts by mass, and particularly preferably 3 to 10 parts by mass, because the external quantum efficiency of the light-emitting element of the present embodiment is more excellent.

(Compound (A))

The compound (a) is a compound represented by Formula (FH) or a polymer compound (hereinafter also referred to as "polymer compound (a)") comprising a structural unit (hereinafter also referred to as "structural unit (a)") having a group obtained by removing 1 or more hydrogen atoms from the compound represented by Formula (FH). The compound (a) is different from the compound (B), and may be, for example, a compound having no condensed heterocyclic skeleton (B).

The composition for a light-emitting element of the present embodiment contains at least 2 compounds (a). The composition for a light-emitting element of the present embodiment may contain 2 or more compounds represented by Formula (FH), may contain 1 or more compounds represented by Formula (FH) and 1 or more polymer compounds (a), and may contain 2 or more polymer compounds (a). In the composition for a light-emitting element of the present embodiment, it is preferable that at least 1 kind of the polymer compound (a) is contained as the compound (a) for the reason that the external quantum efficiency of the light-emitting element is more excellent. That is, the composition for a light-emitting element of the present embodiment preferably contains 1 or more compounds represented by Formula (FH) and 1 or more polymer compounds (a), or contains 2 or more polymer compounds (a).

[ Compound represented by Formula (FH) ]

n^1HUsually, the integer is 10 or less, and is preferably 7 or less, more preferably 5 or less, and still more preferably 3 or less, for the reason of facilitating the synthesis of the compound represented by Formula (FH). In addition, n is a factor that the external quantum efficiency of the light-emitting element of this embodiment is more excellent^1HPreferably an integer of 1 or more.

Ar^1HFor removing and structuring from heterocyclic compounds containing nitrogen atoms in the ringHydrogen atoms n to which the ring-forming atoms are directly bonded^1HAt least one group (hereinafter also referred to as "nitrogen-containing heterocyclic group") may have a substituent.

Ar^1HThe heterocyclic compound in (b) is a heterocyclic compound not containing a fused heterocyclic skeleton (b). Namely, Ar^1HThe heterocyclic compound in (b) is a heterocyclic compound containing a nitrogen atom in the ring and containing no boron atom in the ring. As Ar^1HThe heterocyclic compound in (1) includes, for example: the heterocyclic compound described in the above item of the heterocyclic group includes a heterocyclic compound containing a nitrogen atom in the ring and not containing a boron atom in the ring.

At Ar^1HIn the nitrogen-containing heterocyclic group, the number of carbon atoms is preferably 1 to 60, more preferably 1 to 40, and further preferably 2 to 20, excluding the number of carbon atoms of the substituent.

At Ar^1HIn the above-mentioned nitrogen-containing heterocyclic group, the number of nitrogen atoms is preferably 1 to 10, more preferably 1 to 5, and further preferably 1 to 3, excluding the number of nitrogen atoms of the substituent. At Ar^1HIn the above-mentioned nitrogen-containing heterocyclic group, the number of hetero atoms of the nitrogen-containing heterocyclic group is preferably 1 to 10, more preferably 1 to 5, and further preferably 1 to 3, excluding the number of hetero atoms of the substituent.

Ar^1HThe heterocyclic compound of (1) is preferably a monocyclic or two-to seven-membered heterocyclic compound containing a nitrogen atom in the ring and containing no boron atom in the ring, more preferably a monocyclic or two-to five-membered heterocyclic compound containing a nitrogen atom in the ring and containing no boron atom in the ring, even more preferably a monocyclic, bicyclic or tricyclic heterocyclic compound containing a nitrogen atom in the ring and containing no boron atom in the ring, and particularly preferably oxadiazole, thiadiazole, pyrrole, oxadiazole, triazole, pyridine, diazabenzene, triazine, azanaphthalene, naphthyridine, indole, benzodiazole, carbazole, azacarbazole, diazacazole, phenoxazine, phenothiazine, 9, 10-dihydroacridine, 5, 10-dihydrophenazine, azaanthracene, diazaanthracene, diazananthracene, or the like, because the external quantum efficiency of the light-emitting element of this embodiment is more excellent, Azaphenanthrene or phenanthroline, particularly preferably pyrrole, diazole, triazole, phenanthroline,Pyridine, diazabenzene, triazine, carbazole, azacarbazole, diazacarbazole, phenoxazine, phenothiazine, 9, 10-dihydroacridine or 5, 10-dihydrophenazine, and especially more preferably pyridine, diazabenzene, triazine, carbazole, phenoxazine or phenothiazine.

As Ar^1HExamples of the substituent which may be contained include a substituent other than an aryl group, a monovalent heterocyclic group and a substituted amino group, and preferably include a halogen atom, a cyano group, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an alkenyl group or a cycloalkenyl group, more preferably a cyano group, an alkyl group, a cycloalkyl group, an alkoxy group or a cycloalkoxy group, still more preferably an alkyl group, a cycloalkyl group, an alkoxy group or a cycloalkoxy group, and particularly preferably an alkyl group or a cycloalkyl group, and these groups may further have a substituent.

Ar^1HExamples and preferred ranges of substituents which may be further provided for the substituents which may be provided for the above-mentioned groups and R described later^1AExamples of the substituents which may be present and which may further be present are the same as the preferred ranges.

R^1HFor the reason that the external quantum efficiency of the light-emitting element of this embodiment mode is more excellent, an aryl group or a monovalent heterocyclic group is preferable, and an aryl group is more preferable, and these groups may have a substituent.

R^1HThe aryl group in (1) is preferably a group obtained by removing 1 hydrogen atom directly bonded to a ring-constituting atom from a monocyclic or bicyclic to pentacyclic aromatic hydrocarbon, more preferably a group obtained by removing 1 hydrogen atom directly bonded to a ring-constituting atom from a monocyclic, bicyclic or tricyclic aromatic hydrocarbon, still more preferably a group obtained by removing 1 hydrogen atom directly bonded to a ring-constituting atom from benzene, naphthalene, dihydrophenanthrene or fluorene, and particularly preferably a phenyl group, and these groups may have a substituent.

R^1HThe monovalent heterocyclic group in (b) is a group obtained by removing 1 hydrogen atom directly bonded to an atom constituting a ring from a heterocyclic compound not containing a fused heterocyclic skeleton (b), and the group may have a substituent. R^1HAmong the monovalent heterocyclic groups in (b), examples of the heterocyclic compound not containing the fused heterocyclic skeleton (b) include the above-mentioned heterocyclic compoundsHeterocyclic compounds described in the section of the cyclic group include heterocyclic compounds containing no boron atom and no nitrogen atom in the ring. R^1HThe monovalent heterocyclic group in (b) is preferably a group obtained by removing 1 hydrogen atom directly bonded to a ring-constituting atom from a monocyclic or bicyclic to pentacyclic heterocyclic compound not containing a fused heterocyclic skeleton (b), more preferably a group obtained by removing 1 hydrogen atom directly bonded to a ring-constituting atom from a monocyclic, bicyclic or tricyclic heterocyclic compound not containing a fused heterocyclic skeleton (b), and still more preferably a group obtained by removing 1 hydrogen atom directly bonded to a ring-constituting atom from pyrrole, oxadiazole, triazole, pyridine, diazepine, triazine, azanaphthalene, naphthyridine, dibenzofuran, dibenzothiophene, carbazole, azacarbazole, diazacarbazole, phenoxazine, phenothiazine, 9, 10-dihydroacridine, 5, 10-dihydrophenazine, azaanthracene, diazaanthracene, azaphenanthrene or phenanthroline, particularly preferred is a group obtained by removing 1 hydrogen atom directly bonded to an atom constituting a ring from pyridine, diazabenzene, triazine, dibenzofuran, dibenzothiophene or carbazole, and these groups may have a substituent.

R^1HAmong the substituted amino groups in (1), the substituent of 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 aryl groups as substituents of amino groups with R^1HExamples and preferred ranges of aryl in (1) are the same. Examples and preferred ranges of the monovalent heterocyclic group as a substituent having an amino group are as follows^1HExamples and preferred ranges of the monovalent heterocyclic group in (1) are the same.

As R^1HThe substituent which may be present is preferably a halogen atom, a cyano group, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy 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, and further preferably an alkyl group, a cycloalkyl group, or an aryl group, and these groups may further have a substituent.

R^1HExamples of the aryl group, monovalent heterocyclic group and substituted amino group among the substituents which may be containedSub and preferred ranges with R^1HExamples and preferred ranges of the aryl group, the monovalent heterocyclic group and the substituted amino group in (1) are the same.

As R^1HThe substituent which may be present is preferably a halogen atom, a cyano group, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy 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, and further preferably an alkyl group or a cycloalkyl group, and these groups may further have a substituent, but preferably do not further have a substituent.

R^1HExamples and preferred ranges of aryl, monovalent heterocyclic group and substituted amino group among the substituents which may be present and which may further have substituents are as defined above for R^1HExamples and preferred ranges of the aryl group, the monovalent heterocyclic group and the substituted amino group in (1) are the same.

Examples of the compound (a) include compounds represented by the following formulae and compounds H2 to H8 described later. In the formula, Z¹Represents an oxygen atom or a sulfur atom. In the formula, Z²Represents a group represented by-CH ═ or a group represented by-N ═ or a salt thereof.

[ chemical formula 7]

[ chemical formula 8]

[ chemical formula 9]

[ Polymer Compound (A) ]

The weight average molecular weight of the polymer compound (A) in terms of polystyrene is preferably 1X 10⁴～1×10⁷More preferably 2X 10⁴～5×10⁶More preferably 1X 10⁵～2×10⁵。

The polymer compound (a) may be any of a block copolymer, a random copolymer, an alternating copolymer, and a graft copolymer, or may be in other forms, and is preferably a copolymer obtained by copolymerizing two or more kinds of raw material monomers.

The 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 compound represented by Formula (FH), more preferably a structural unit having a group obtained by removing 1 or more and 3 or less hydrogen atoms from the compound represented by Formula (FH), and still more preferably a structural unit having a group obtained by removing 1 or 2 hydrogen atoms from the compound represented by Formula (FH), for the reason that the polymer compound (a) can be easily synthesized.

The structural unit (A) is preferably a structural unit represented by formula (FH-1), formula (FH-2), or formula (FH-3), and more preferably a structural unit represented by formula (FH-1) or formula (FH-2), because the synthesis of the polymer compound (A) is easy and the external quantum efficiency of the light-emitting element of the present embodiment is more excellent.

[ chemical formula 10]

In the formula (I), the compound is shown in the specification,

M^FH1represents a group obtained by removing 1 hydrogen atom from the compound represented by Formula (FH).

M^FH2Represents a group obtained by removing 2 hydrogen atoms from a compound represented by Formula (FH).

M^FH3Represents a group obtained by removing 3 hydrogen atoms from a compound represented by Formula (FH).

L^FH1Each independently represents alkylene, cycloalkylene, arylene, a divalent heterocyclic group, -N (R)^FH1) -a group represented by, an oxygen atom or a sulfur atom, and these groups may have a substituent. When a plurality of such substituents are present, they may be the same or different, and may be bonded to each otherThe bonded atoms together form a ring. R^FH1Represents 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 a plurality of such substituents are present, they may be the same or different, and may be bonded to each other to form a ring together with the atom to which they are bonded. L is^FH1When there are a plurality of them, they may be the same or different.

n^FH1Represents an integer of 0 to 10 inclusive.

Ar^FH1Represents a hydrocarbon group or a heterocyclic group, and these groups may have a substituent. When a plurality of such substituents are present, they may be the same or different, and may be bonded to each other to form a ring together with the atom to which they are bonded.

L^FH1Preferably an alkylene group, a cycloalkylene group, an arylene group or a divalent heterocyclic group, more preferably an alkylene group or an arylene group, and these groups may have a substituent.

L^FH1Examples and preferred ranges of arylene and divalent heterocyclic groups in (1) are each with Ar^Y1Examples and preferred ranges of the arylene group and the divalent heterocyclic group in (1) are the same.

R^FH1Examples and preferred ranges of (A) and (B) and R described later^X1The examples and preferred ranges of (a) are the same.

n^FH1Preferably an integer of 0 to 5, preferably an integer of 0 to 3, more preferably 0 or 1, and further preferably 0.

Ar^FH1In (3), the hydrocarbon group is a group obtained by removing 3 hydrogen atoms from an aliphatic hydrocarbon or an aromatic hydrocarbon, and the group may have a substituent.

Ar^FH1In the case where the hydrocarbon group is a group obtained by removing 3 hydrogen atoms from an aliphatic hydrocarbon, examples of the hydrocarbon group include a group obtained by removing 1 hydrogen atom from an alkylene group described in the above item of alkylene group, and a group obtained by removing 1 hydrogen atom from a cycloalkylene group described in the above item of cycloalkylene group.

Ar^FH1In the case where the hydrocarbon group is a group obtained by removing 3 hydrogen atoms from an aromatic hydrocarbon, the hydrocarbon group is defined asAr described later is exemplified by^Y1The arylene group in (1) is a group obtained by removing 1 hydrogen atom from the group described above.

As Ar^FH1The heterocyclic group in (1) includes Ar described later^Y1The divalent heterocyclic group in (1) is a group obtained by removing 1 hydrogen atom from the group described above.

L^FH1And Ar^FH1Examples and preferred examples of the substituent which may be contained and Ar described later^Y1Examples and preferred ranges of substituents that the groups shown may have are the same.

Examples of the structural unit (a) include structural units represented by the following formulae, and structural units derived from compounds H1 to H8 and compound M6 described later. In the formula, Z¹Represents an oxygen atom or a sulfur atom. In the formula, Z²Represents a group represented by-CH ═ or a group represented by-N ═ or a salt thereof.

[ chemical formula 11]

The content of the structural unit (a) is preferably 0.1 to 100 mol%, more preferably 1 to 100 mol%, further preferably 10 to 100 mol%, and particularly preferably 20 to 100 mol% based on the total amount of the structural units contained in the polymer compound (a), for the reason that the external quantum efficiency of the light-emitting element of the present embodiment is more excellent. The structural unit (a) may include only 1 type or 2 or more types of the polymer compound (a).

The polymer compound (a) preferably further contains a structural unit represented by formula (Y) described later, because the external quantum efficiency of the light-emitting element of the present embodiment is further excellent.

The polymer compound (a) may further contain a structural unit represented by the formula (X) described later.

The polymer compound (a) may further contain a structural unit represented by formula (X) and a structural unit represented by formula (Y).

When the polymer compound (a) contains the structural unit represented by the formula (X), the content of the structural unit represented by the formula (X) is preferably 0.1 to 99 mol%, more preferably 1 to 50 mol%, and further preferably 3 to 30 mol% based on the total amount of the structural units contained in the polymer compound (a) for the reason of excellent hole transporting property.

The structural unit represented by the formula (X) may include only 1 species or 2 or more species in the polymer compound (a).

The polymer compound (A) contains a structural unit represented by the formula (Y) and Ar^Y1In the case of an arylene group, the content of the structural unit represented by the formula (Y) is preferably 1 to 99 mol%, more preferably 10 to 95 mol%, further preferably 30 to 90 mol%, and particularly preferably 50 to 80 mol% based on the total amount of the polymer compound (a), for the reason that the external quantum efficiency of the light-emitting element of the present embodiment is more excellent.

The polymer compound (A) contains a structural unit represented by the formula (Y) and Ar^Y1In the case of a divalent heterocyclic group or a divalent group in which at least 1 arylene group and at least 1 divalent heterocyclic group are directly bonded to each other, the content of the structural unit represented by the formula (Y) is preferably 0.1 to 99 mol%, more preferably 1 to 50 mol%, and further preferably 3 to 30 mol% based on the total amount of the structural units contained in the polymer compound (a), for the reason that the polymer compound (a) has excellent charge transport properties.

The structural unit represented by the formula (Y) may include only 1 type or 2 or more types in the polymer compound (a).

Structural unit of the formula (Y)

[ chemical formula 12]

In the formula, Ar^Y1Represents an arylene group, a divalent heterocyclic group, or a divalent group in which at least 1 arylene group and at least 1 divalent heterocyclic group are directly bonded, and these groups may have a substituent. When a plurality of such substituents are present, they may be in phaseAnd may be different from each other, and may bond to each other to form a ring together with the atoms to which each is bonded.

Ar^Y1The arylene group in (b) is preferably a group obtained by removing 2 hydrogen atoms directly bonded to ring-constituting atoms from a monocyclic or bicyclic to hexacyclic aromatic hydrocarbon, more preferably a group obtained by removing 2 hydrogen atoms directly bonded to ring-constituting atoms from a monocyclic, bicyclic or tricyclic aromatic hydrocarbon, further preferably a group obtained by removing 2 hydrogen atoms directly bonded to ring-constituting atoms from benzene, naphthalene, anthracene, phenanthrene, dihydrophenanthrene or fluorene, particularly preferably a group obtained by removing 2 hydrogen atoms directly bonded to ring-constituting atoms from benzene, phenanthrene, dihydrophenanthrene or fluorene, and these may have a substituent(s).

Ar^Y1The divalent heterocyclic group in (2) is preferably a group obtained by removing 2 hydrogen atoms directly bonded to a ring-constituting atom (preferably a carbon atom) from a heterocyclic compound containing no nitrogen atom in the ring, and the group may have a substituent.

Examples of the heterocyclic compound not containing a nitrogen atom in the ring include: heterocyclic compounds not containing a nitrogen atom in the ring among the heterocyclic compounds described in the above items of heterocyclic groups. As a heterocyclic compound not containing a nitrogen atom in a ring, a monocyclic, bicyclic, or tricyclic heterocyclic compound not containing a nitrogen atom in a ring is preferable, a monocyclic, bicyclic, or tricyclic heterocyclic compound not containing a nitrogen atom in a ring is more preferable, and furan, thiophene, benzofuran, benzothiophene, dibenzofuran, or dibenzothiophene is further preferable, because the external quantum efficiency of the light-emitting element of the present embodiment is more excellent.

Ar^Y1In the divalent group in which at least 1 arylene group and at least 1 divalent heterocyclic group are directly bonded, preferable ranges of the arylene group and the divalent heterocyclic group are each with Ar^Y1The preferable ranges of the arylene group and the divalent heterocyclic group in (1) are the same.

Ar^Y1The hair of the present embodimentThe arylene group which may have a substituent is preferable because the external quantum efficiency of the optical element is more excellent.

Ar^Y1The substituent which the group shown 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 group, 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, further 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, and these groups may further have a substituent.

Ar^Y1Among the substituents that the group may have, the aryl group is preferably a group obtained by removing 1 hydrogen atom directly bonded to a ring-constituting atom from a monocyclic or bicyclic to hexacyclic aromatic hydrocarbon, more preferably a group obtained by removing 1 hydrogen atom directly bonded to a ring-constituting atom from a monocyclic, bicyclic or tricyclic aromatic hydrocarbon, further preferably a group obtained by removing 1 hydrogen atom directly bonded to a ring-constituting atom from benzene, naphthalene, anthracene, phenanthrene, dihydrophenanthrene or fluorene, particularly preferably a group obtained by removing 1 hydrogen atom directly bonded to a ring-constituting atom from benzene, phenanthrene, dihydrophenanthrene or fluorene, and may further have a substituent, because the external quantum efficiency of the light-emitting element of this embodiment is more excellent.

Ar^Y1Among the substituents which the group shown may have, a monovalent heterocyclic group is preferably a group obtained by removing 1 hydrogen atom directly bonded to an atom (preferably a carbon atom) constituting a ring from a heterocyclic compound containing no nitrogen atom in the ring, and the group may have a substituent.

Ar^Y1Examples and preferred ranges of heterocyclic compounds containing no nitrogen atom in the ring among monovalent heterocyclic groups among substituents which the groups shown may have are as follows^Y1Examples of the heterocyclic compound not containing a nitrogen atom in the ring described in the item of the divalent heterocyclic group in (1) are the same as the preferable ranges.

Ar^Y1Among the substituents which the indicated groups may haveAmong the substituted amino groups, the substituent of 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 preferable ranges of the aryl group and the monovalent heterocyclic group in the substituent having the amino group are each with Ar^Y1Examples and preferable ranges of the aryl group and the monovalent heterocyclic group in the substituents which the illustrated groups may have are the same.

As Ar^Y1The substituent which the group shown may have is preferably a substituent which may further have 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, more preferably an alkyl group, a cycloalkyl group, an aryl group, a monovalent heterocyclic group or a substituted amino group, further preferably an alkyl group or a cycloalkyl group, and these groups may further have a substituent, but preferably do not further have a substituent.

Ar^Y1Examples and preferable ranges of the aryl group, the monovalent heterocyclic group and the substituted amino group in the substituents which the illustrated groups may have may further have are each with Ar^Y1Examples and preferable ranges of the aryl group, the monovalent heterocyclic group and the substituted amino group in the substituents which the illustrated groups may have are the same.

The structural unit represented by the formula (Y) is preferably a structural unit represented by the formula (Y-1) or the formula (Y-2) because the external quantum efficiency of the light-emitting element of the present embodiment is further excellent.

[ chemical formula 13]

In the formula (I), the compound is shown in the specification,

R^Y1represents 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 may have a substituent. When a plurality of such substituents are present, they may be the same or different, and may be bonded to each other to form a ring together with the atom to which they are bonded. Plural R's present^Y1May be the same or different and may beTo form a ring together with the carbon atoms to which they are bonded.

X^Y1represents-C (R)^Y2)₂－、－C(R^Y2)＝C(R^Y2) -or-C (R)^Y2)₂－C(R^Y2)₂-a group as shown. R^Y2Represents 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 may have a substituent. When a plurality of such substituents are present, they may be the same or different, and may be bonded to each other to form a ring together with the atom to which they are bonded. Plural R's present^Y2May 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^Y1It 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, further preferably a hydrogen atom or an alkyl group, and these groups may have a substituent.

R^Y2Preferably, the alkyl group, the cycloalkyl group, the alkoxy group, the cycloalkoxy group, the aryl group, a monovalent heterocyclic group or a substituted amino group, more preferably, the alkyl group, the cycloalkyl group, the aryl group or a monovalent heterocyclic group, and further preferably, the alkyl group, the cycloalkyl group or the aryl group may have a substituent.

R^Y1And R^Y2Examples and preferred ranges of aryl, monovalent heterocyclic group and substituted amino in (1) are each with Ar^Y1Examples and preferable ranges of the aryl group, the monovalent heterocyclic group and the substituted amino group in the substituents which the illustrated groups may have are the same.

R^Y1And R^Y2Examples and preferred ranges of substituents that may be present with Ar^Y1Examples and preferred ranges of substituents that the groups shown may have are the same.

X^Y1The light-emitting element of the present embodiment is preferably — C (R) because of its superior external quantum efficiency^Y2)₂-or-C (R)^Y2)₂－C(R^Y2)₂A group represented bypreferably-C (R)^Y2)₂-a group as shown.

Examples of the structural unit represented by the formula (Y) include structural units represented by the following formulae, and structural units derived from compounds M1, M2, M4, and M5 described later. In the following formula, Z¹Represents an oxygen atom or a sulfur atom. Z²Represents a group represented by-CH ═ or a group represented by-N ═ or a salt thereof.

[ chemical formula 14]

[ chemical formula 15]

Structural unit of the formula (X)

[ chemical formula 16]

In the formula (I), the compound is shown in the specification,

a^X1and a^X2Each independently represents an integer of 0 or more.

Ar^X1And Ar^X3Each independently represents an arylene group or a divalent heterocyclic group, and these groups may have a substituent. When a plurality of such substituents are present, they may be the same or different, and may be bonded to each other to form a ring together with the atom to which they are bonded.

Ar^X2And Ar^X4Each independently represents an arylene group, a divalent heterocyclic group, or a divalent group in which at least 1 arylene group and at least 1 divalent heterocyclic group are directly bonded, and these groups may have a substituent. When a plurality of such substituents are present, they may be the same or different, and may be bonded to each other to form a ring together with the atom to which they are bonded. Ar (Ar)^X2And Ar^X4When a plurality of the compounds exist, they may be the same or different.

R^X1、R^X2And R^X3Each independently 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 a plurality of such substituents are present, they may be the same or different, and may be bonded to each other to form a ring together with the atom to which they are bonded. R^X2And R^X3When a plurality of the compounds exist, they may be the same or different.

a^X1And a^X2The number is usually an integer of 0 to 5, and is preferably an integer of 0 to 3, more preferably an integer of 0 to 2, and still more preferably 0 or 1, for the reason that the external quantum efficiency of the light-emitting element of the present embodiment is more excellent.

R^X1、R^X2And R^X3Preferably, the alkyl group, the cycloalkyl group, the aryl group or the monovalent heterocyclic group is more preferably an aryl group or a monovalent heterocyclic group, and still more preferably an aryl group, and these groups may have a substituent.

R^X1、R^X2And R^X3Examples and preferred ranges of aryl and monovalent heterocyclic groups in (1) are each with Ar^Y1Examples and preferable ranges of the aryl group and the monovalent heterocyclic group in the substituents which the illustrated groups may have are the same.

Ar^X1、Ar^X2、Ar^X3And Ar^X4Examples and preferred ranges of arylene and divalent heterocyclic groups in (1) are each with Ar^Y1Examples and preferred ranges of the arylene group and the divalent heterocyclic group in (1) are the same.

Ar^X2And Ar^X4Examples and preferred ranges of the arylene group and the divalent heterocyclic group in the divalent group in which at least 1 arylene group and at least 1 divalent heterocyclic group are directly bonded are each with Ar^Y1Examples and preferred ranges of the arylene group and the divalent heterocyclic group in (1) are the same.

As Ar^X2And Ar^X4In the above (1), a divalent group in which at least 1 arylene group and at least 1 divalent heterocyclic group are directly bonded to each other is exemplified by a divalent group bonded to Ar^Y1The same as the divalent group in which at least 1 arylene group and at least 1 divalent heterocyclic group are directly bonded in (a) is used.

Ar^X1、Ar^X2、Ar^X3And Ar^X4Preferred is an arylene group which may have a substituent.

Ar^X1～Ar^X4And R^X1～R^X3Examples and preferred ranges of substituents that the groups shown may have with Ar^Y1Examples and preferred ranges of substituents that the groups shown may have are the same.

Examples of the structural unit represented by the formula (X) include a structural unit represented by the following formula and a structural unit derived from compound M3 described later.

[ chemical formula 17]

[ chemical formula 18]

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

[ Table 1]

In table 1, p ', q', r ', and s' represent the molar ratio (mol%) of each structural unit. p ' + q ' + r ' + s ' + 100 and 70 ≦ p ' + q ' + r ' ≦ 100.

The polymer compound (a) may be any of a block copolymer, a random copolymer, an alternating copolymer, and a graft copolymer, or may be in other forms, and is preferably a copolymer obtained by copolymerizing two or more kinds of raw material monomers.

The weight average molecular weight of the polymer compound (A) in terms of polystyrene is preferably 1X 10⁴～1×10⁷More preferably 2X 10⁴～5×10⁶More preferably 1X 10⁵～2×10⁵。

[ Process for producing Polymer Compound (A) ]

The polymer compound (a) can be produced by a known polymerization method described in chemical review (chem. rev.), volume 109, page 897-1091 (2009), and the like, and examples thereof include a method of polymerizing by a coupling reaction using a transition metal catalyst, such as Suzuki reaction, Yamamoto reaction, Buchwald reaction, Stille reaction, Negishi reaction, and Kumada reaction.

In the above polymerization method, examples of the method of charging the monomer include: a method of putting the total amount of the monomers into the reaction system at one time; a method in which a part of the monomers is charged and reacted, and then the remaining monomers are charged at once, continuously or in portions; a method of charging the monomer continuously or in portions, and the like.

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

The post-treatment of the polymerization reaction is carried out by using, alone or in combination, known methods such as: a method of removing water-soluble impurities by liquid separation; a method in which the reaction solution after the polymerization reaction is added to a lower alcohol such as methanol, and the precipitated precipitate is filtered and then dried. When the purity of the polymer compound (a) is low, it can be purified by a usual method such as recrystallization, reprecipitation, continuous extraction with a soxhlet extractor, column chromatography, or the like.

[ Compound (B) ]

The compound (B) is a compound having a condensed heterocyclic skeleton (B) containing a boron atom and a nitrogen atom in the ring.

In the compound (B), at least 1 of the nitrogen atoms contained in the fused heterocyclic skeleton (B) is preferably a nitrogen atom which does not form a double bond, and more preferably all of the nitrogen atoms contained in the fused heterocyclic skeleton (B) are nitrogen atoms which do not form a double bond.

The number of carbon atoms of the condensed heterocyclic skeleton (b) is usually 1 to 60, preferably 5 to 40, and more preferably 10 to 25, excluding the number of carbon atoms of the substituent.

The number of hetero atoms of the condensed heterocyclic skeleton (b) is usually 2 to 30, preferably 2 to 15, more preferably 2 to 10, further preferably 2 to 5, particularly preferably 2 or 3, excluding the number of hetero atoms of the substituent.

The number of boron atoms of the condensed heterocyclic skeleton (b) is usually 1 to 10, preferably 1 to 5, more preferably 1 to 3, and still more preferably 1, excluding the number of boron atoms of the substituent.

The number of nitrogen atoms of the condensed heterocyclic skeleton (b) is usually 1 to 20, preferably 1 to 10, more preferably 1 to 5, further preferably 1 to 3, and particularly preferably 2, excluding the number of nitrogen atoms of the substituent.

The condensed heterocyclic skeleton (b) is preferably a three-to twelve-ring condensed heterocyclic skeleton, more preferably a three-to six-ring condensed heterocyclic skeleton, and still more preferably a five-ring condensed heterocyclic skeleton, because the light-emitting element of the present embodiment has a better external quantum efficiency.

The compound (B) may also be referred to as a compound having a heterocyclic group (B') containing a fused heterocyclic skeleton (B).

The heterocyclic group (b') may be a group obtained by removing 1 or more hydrogen atoms directly bonded to the atoms constituting the ring from a polycyclic heterocyclic compound containing a boron atom and a nitrogen atom in the ring, and the group may have a substituent.

The substituent which the heterocyclic group (b') may have is preferably a halogen atom, a cyano group, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, a monovalent 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, and further preferably an alkyl group, an aryl group or a substituted amino group, and these groups may further have a substituent.

Among the substituents which the heterocyclic group (b') may have, the aryl group is preferably a group obtained by removing 1 hydrogen atom directly bonded to a ring-constituting atom from a monocyclic or bicyclic to hexacyclic aromatic hydrocarbon, more preferably a group obtained by removing 1 hydrogen atom directly bonded to a ring-constituting atom from a monocyclic, bicyclic or tricyclic aromatic hydrocarbon, still more preferably a group obtained by removing 1 hydrogen atom directly bonded to a ring-constituting atom from benzene, naphthalene, anthracene, phenanthrene or fluorene, particularly preferably a phenyl group, and these groups may have a substituent.

Among the substituents that the heterocyclic group (b') may have, a monovalent heterocyclic group is preferably a group obtained by removing 1 hydrogen atom directly bonded to a ring-constituting atom from a monocyclic or bicyclic to hexacyclic heterocyclic compound, more preferably a group obtained by removing 1 hydrogen atom directly bonded to a ring-constituting atom from a monocyclic, bicyclic or tricyclic heterocyclic compound, still more preferably a group obtained by removing 1 hydrogen atom directly bonded to a ring-constituting atom from pyridine, diazabenzene, triazine, azanaphthalene, naphthyridine, carbazole, dibenzofuran, dibenzothiophene, phenoxazine or phenothiazine, particularly preferably a group obtained by removing 1 hydrogen atom directly bonded to a ring-constituting atom from pyridine, diazabenzene or triazine, and these groups may have a substituent.

Among the substituted amino groups that the heterocyclic group (b') may have, as the substituent group that the amino group has, preferably an aryl group or a monovalent heterocyclic group, more preferably an aryl group, and these groups may further have a substituent group. Examples and preferable ranges of the aryl group and the monovalent heterocyclic group in the substituent which the amino group has are the same as those of the aryl group and the monovalent heterocyclic group in the substituent which the heterocyclic group (b') may have, respectively.

The substituent which the heterocyclic group (b') may have is preferably a halogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy 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, and further preferably an alkyl group or a cycloalkyl group, and these groups may further have a substituent, but preferably do not further have a substituent.

Examples and preferable ranges of the aryl group, the monovalent heterocyclic group and the substituted amino group in the substituents which the heterocyclic group (b ') may have may further be the same as examples and preferable ranges of the aryl group, the monovalent heterocyclic group and the substituted amino group in the substituents which the heterocyclic group (b') may have, respectively.

The "nitrogen atom not forming a double bond" means a nitrogen atom bonded to the other 3 atoms by single bonds, respectively.

"containing a nitrogen atom having no double bond formed in a ring" means that-N (-R) is contained in the ring^N) - (in the formula, R^NRepresenting a hydrogen atom or a substituent) or a group represented by the following formula.

[ chemical formula 19]

The compound (B) is preferably a Thermally Active Delayed Fluorescence (TADF) compound because the external quantum efficiency of the light-emitting element of the present embodiment is more excellent.

Delta E of Compound (B)_STThe thickness may be 2.0eV or less, may be 1.5eV or less, may be 1.0eV or less, may be 0.80eV or less, and may be 0.60eV or less, and is preferably 0.50eV or less for the reason that the external quantum efficiency of the light-emitting element of the present embodiment is more excellent. In addition,. DELTA.E of Compound (B)_STThe dielectric constant may be 0.001eV or more, may be 0.01eV or more, may be 0.10eV or more, may be 0.20eV or more, may be 0.30eV or more, or may be 0.40eV or more.

The compound (B) is preferably a low-molecular compound.

The molecular weight of the compound (B) is preferably 1X 10²～5×10³More preferably 2X 10²～3×10³More preferably 3X 10²～1.5×10³Particularly preferably 4X 10²～1×10³。

The compound (B) is preferably a compound represented by formula (1-1), formula (1-2), or formula (1-3), more preferably a compound represented by formula (1-2) or formula (1-3), and still more preferably a compound represented by formula (1-2), because the external quantum efficiency of the light-emitting element of the present embodiment is more excellent.

Ar¹、Ar²And Ar³For the reason that the external quantum efficiency of the light-emitting element of the present embodiment is more excellent, a group obtained by removing 1 or more hydrogen atoms directly bonded to atoms constituting a ring from a monocyclic, bicyclic, or tricyclic aromatic hydrocarbon or a monocyclic, bicyclic, or tricyclic heterocyclic compound is preferable, a group obtained by removing 1 or more hydrogen atoms directly bonded to atoms constituting a ring from a monocyclic aromatic hydrocarbon or monocyclic heterocyclic compound is more preferable, a group obtained by removing 1 or more hydrogen atoms directly bonded to atoms constituting a ring from benzene, pyridine, or diazepine is even more preferable, a group obtained by removing 1 or more hydrogen atoms directly bonded to atoms constituting a ring from benzene is particularly preferable, and these groups may have a substituent.

Ar¹、Ar²And Ar³Examples and preferred ranges of substituents which may be present are the same as those of substituents which may be present in the heterocyclic group (b').

Y²And Y³Preferably a single bond, an oxygen atom, a sulfur atom, a group represented by-N (Ry) -or a methylene group, more preferably a single bond, an oxygen atom, a sulfur atom or a group represented by-N (Ry) -and still more preferably an oxygen atom, a sulfur atom or a group represented by-N (Ry) -and particularly preferably a group represented by-N (Ry) -which may have a substituent.

Y¹、Y²And Y³Examples and preferred ranges of substituents which may be present are the same as those of substituents which may be present in the heterocyclic group (b').

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, and further preferably an aryl group, and these groups may have a substituent.

Examples and preferable ranges of the aryl group and the monovalent heterocyclic group in Ry are the same as those of the aryl group and the monovalent heterocyclic group, respectively, among the substituents which the heterocyclic group (b') may have.

Examples and preferred ranges of substituents that Ry may have are the same as those of substituents that heterocyclic group (b') may have.

Ry may be bonded to Ar directly or via a linking group¹、Ar²Or Ar³Bonded, but preferably not bonded. Examples of the linking group include a group represented by-O-, a group represented by-S-, a group represented by-N (Ry) -, an alkylene group, a cycloalkylene group, an arylene group, and a divalent heterocyclic group, and preferably a group represented by-O-, a group represented by-S-, a group represented by-N (Ry) -, or a methylene group, and these groups may have a substituent.

Examples of the compound B include compounds represented by the following formulae and compounds B1 and B2 described later.

[ chemical formula 20]

[ chemical formula 21]

In the formula, Z¹Represents an oxygen atom or a sulfur atom.

[ other ingredients ]

The composition for a light-emitting element of the present embodiment may contain 2 or more compounds (a) and (B) and at least 1 selected from a hole-transporting material, a hole-injecting material, an electron-transporting material, an electron-injecting material, a light-emitting material, an antioxidant, and a solvent. Wherein 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 (a) and the compound (B).

[ ink ]

A composition containing 2 or more compounds (a), compounds (B) and a solvent (hereinafter referred to as "ink") is suitable for the production of a light-emitting element by using a wet method such as a spin coating method, a flow coating method, a microgravure 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 printing method, an offset printing method, an ink jet printing method, a capillary coating method, a nozzle coating method, or the like. The viscosity of the ink may be adjusted depending on the type of printing method, and is preferably 1 to 20mPa · s at 25 ℃.

The solvent contained in the ink is preferably a solvent capable of dissolving or uniformly dispersing solid components in the ink. Examples of the solvent include a chlorine-based solvent, an ether-based solvent, an aromatic hydrocarbon-based solvent, an aliphatic hydrocarbon-based solvent, a ketone-based solvent, an ester-based solvent, a polyol-based solvent, an alcohol-based solvent, a sulfoxide-based solvent, and an amide-based solvent.

The amount of the solvent to be mixed in the ink is usually 1000 to 100000 parts by mass when the total amount of the compound (a) and the compound (B) is 100 parts by mass.

One solvent may be used alone, or two or more solvents may be used in combination.

Hole transport Material

The hole transport material is classified into a low molecular compound and a high molecular compound, and is preferably a high molecular compound having a crosslinking group.

Examples of the polymer compound include polyvinylcarbazole and derivatives thereof; polyarylene having an aromatic amine structure in a side chain or a main chain, and a derivative thereof. The polymer compound may be a compound to which an electron-accepting moiety such as fullerene, tetrafluorotetracyanoquinodimethane, tetracyanoethylene, trinitrofluorenone, or the like is bonded.

In the case where the composition for a light-emitting element of the present embodiment contains a hole-transporting material, the amount of the hole-transporting material to be blended is usually 1 to 1000 parts by mass, assuming that the total amount of the compound (a) and the compound (B) is 100 parts by mass.

One kind of the hole transport material may be used alone, or two or more kinds may be used in combination.

Electron transport Material

The electron transport materials are classified into low molecular compounds and high molecular compounds. The electron transport material may have a crosslinking group.

Examples of the low-molecular compound include metal complexes having 8-hydroxyquinoline as a ligand, oxadiazoles, anthraquinone dimethanes, benzoquinones, naphthoquinones, anthraquinones, tetracyanoanthraquinone dimethanes, fluorenones, dicyanstilbene and diphenoquinones, and derivatives thereof.

Examples of the polymer compound include polyphenylene, polyfluorene, and derivatives thereof. The polymer compound may be doped with a metal.

In the case where the composition for a light-emitting element of the present embodiment contains an electron-transporting material, the amount of the electron-transporting material to be added is usually 1 to 1000 parts by mass, assuming that the total amount of the compound (a) and the compound (B) is 100 parts by mass.

One kind of the electron transporting material may be used alone, or two or more kinds may be used in combination.

Hole injection material and electron injection material

The hole injection material and the electron injection material are each classified into a low molecular compound and a high molecular compound. The hole injection material and the electron injection material may have a crosslinking group.

Examples of the low-molecular-weight compound include metal phthalocyanines such as copper phthalocyanine; carbon; metal oxides of molybdenum, tungsten, and the like; metal fluorides such as lithium fluoride, sodium fluoride, cesium fluoride and potassium fluoride.

Examples of the polymer compound include polyaniline, polythiophene, polypyrrole, polyphenylene vinylene, polythiophene vinylene, polyquinoline, polyquinoxaline, and derivatives thereof; and a conductive polymer such as a polymer having an aromatic amine structure in a main chain or a side chain.

In the composition for a light-emitting element of the present embodiment, when the hole-injecting material and/or the electron-injecting material is contained, the amount of the hole-injecting material and the electron-injecting material to be mixed is usually 1 part by mass to 1000 parts by mass, respectively, when the total amount of the compound (a) and the compound (B) is 100 parts by mass.

The hole injection material and the electron injection material may be used singly or in combination of two or more.

Doping of ions

When the hole injection material or the electron injection material contains a conductive polymer, the conductivity of the conductive polymer is preferably 1 × 10^-5S/cm～1×10³S/cm. In order to set the conductivity of the conductive polymer within this range, an appropriate amount of ions may be doped into the conductive polymer. The kind of the doped ion is an anion in the case of a hole injection material, and a cation in the case of an electron injection material. Examples of the anion include a polystyrene sulfonate ion, an alkylbenzene sulfonate ion, and a camphor sulfonate ion. Examples of the cation include lithium ion, sodium ion, potassium ion, and tetrabutylammonium ion.

One kind of the doping ions may be used alone, or two or more kinds may be used in combination.

Luminescent materials

Light emitting materials are classified into low molecular compounds and high molecular compounds. The light-emitting material may have a crosslinking group.

Examples of the low-molecular compound include naphthalene and its derivatives, anthracene and its derivatives, perylene and its derivatives, and a triplet light-emitting complex having iridium, platinum, or europium as a central metal.

Examples of the polymer compound include arylene groups including phenylene, naphthalenediyl, fluorenediyl, phenanthrenediyl, dihydrophenanthrenediyl, anthracenediyl, and pyrenediyl; aromatic amine residues such as groups obtained by removing 2 hydrogen atoms from aromatic amines; and divalent heterocyclic groups such as carbazole diyl, phenoxazinediyl, and phenothiazindiyl.

When the composition for a light-emitting element of the present embodiment contains a light-emitting material, the content of the light-emitting material is usually 1 to 1000 parts by mass when the total amount of the compound (a) and the compound (B) is 100 parts by mass.

One kind of the luminescent material may be used alone, or two or more kinds may be used in combination.

An antioxidant

The antioxidant may be any compound that is soluble in the same solvent as the compound (a) and the compound (B) and does not inhibit light emission or charge transfer, and examples thereof include a phenol-based antioxidant and a phosphorus-based antioxidant.

In the light-emitting element composition of the present embodiment, when an antioxidant is contained, the amount of the antioxidant to be blended is usually 0.001 to 10 parts by mass, assuming that the total amount of the compound (a) and the compound (B) is 100 parts by mass.

The antioxidant may be used alone or in combination of two or more.

< membrane >

The film of the present embodiment contains the composition for a light-emitting element. The film of the present embodiment is suitable as a light-emitting layer in a light-emitting element. The film of the present embodiment can be produced by a wet method using ink, for example. The film of the present embodiment can be produced by a dry method such as a vacuum deposition method. Examples of the method for producing the film of the present embodiment by a dry method include a method for depositing the above-described composition for a light-emitting element and a method for co-depositing the compound (a) and the compound (B).

The thickness of the film is usually 1nm to 10 μm.

< light emitting element >

The light-emitting element of the present embodiment contains the composition for a light-emitting element.

The light-emitting element of the present embodiment may include, for example, an anode, a cathode, and an organic layer containing the light-emitting element composition provided between the anode and the cathode.

[ layer constitution ]

The layer containing the composition for a light-emitting element of the present embodiment is usually 1 or more layers selected from a light-emitting layer, a hole-transporting layer, a hole-injecting layer, an electron-transporting layer, and an electron-injecting layer, and is preferably a light-emitting layer. Each of these layers contains a light emitting material, a hole transporting material, a hole injecting material, an electron transporting material, and an electron injecting material. Each of these layers can be formed by the same method as in the above-described film formation using a light-emitting material, a hole-transporting material, a hole-injecting material, an electron-transporting material, and an electron-injecting material.

The light-emitting element has a light-emitting layer between an anode and a cathode. The light-emitting element of this embodiment preferably has at least 1 of the hole injection layer and the hole transport layer between the anode and the light-emitting layer from the viewpoint of hole injection property and hole transport property, and preferably has at least 1 of the electron injection layer and the electron transport layer between the cathode and the light-emitting layer from the viewpoint of electron injection property and electron transport property.

The materials of the hole transport layer, the electron transport layer, the light-emitting layer, the hole injection layer, and the electron injection layer include the composition for a light-emitting element of the present embodiment, and the hole transport material, the electron transport material, the light-emitting material, the hole injection material, the electron injection material, and the like described above.

In the case where the material for the hole transport layer, the material for the electron transport layer, and the material for the light-emitting layer are soluble in the solvents used for forming the layers adjacent to the hole transport layer, the electron transport layer, and the light-emitting layer, respectively, in the production of the light-emitting element, it is preferable that the materials have a crosslinking group in order to avoid the dissolution of the materials in the solvents. After each layer is formed using a material having a crosslinking group, the crosslinking group is crosslinked, whereby the layer can be insolubilized.

In the light-emitting element of the present embodiment, when a low molecular weight compound is used, examples of a method for forming each layer such as the light-emitting layer, the hole transport layer, the electron transport layer, the hole injection layer, and the electron injection layer include a dry method such as a vacuum deposition method using powder, a wet method such as a method of forming a film using a solution or a molten state, and when a high molecular weight compound is used, examples of a wet method such as a method of forming a film using a solution or a molten state. The order, number, and thickness of the stacked layers are adjusted in consideration of, for example, light emission efficiency, driving voltage, and luminance lifetime.

[ substrate/electrode ]

The substrate in the light-emitting element may be any substrate that can be provided with an electrode and that does not chemically change when the organic layer is formed, and examples of the substrate include substrates made of materials such as glass, plastic, and silicon. In the case of an opaque substrate, the electrode furthest from the substrate is preferably transparent or translucent.

Examples of the material of the anode include conductive metal oxides and translucent metals, and indium oxide, zinc oxide, and tin oxide are preferable; conductive compounds such as Indium Tin Oxide (ITO) and indium zinc oxide; silver and palladium and copper complexes (APC); NESA, gold, platinum, silver, copper.

Examples of the material of the cathode include metals such as lithium, sodium, potassium, rubidium, cesium, beryllium, magnesium, calcium, strontium, barium, aluminum, zinc, and indium; alloys of 2 or more of them; alloys of 1 or more of them with 1 or more of silver, copper, manganese, titanium, cobalt, nickel, tungsten, and tin; and graphite intercalation compounds. Examples of the alloy include a magnesium-silver alloy, a magnesium-indium alloy, a magnesium-aluminum alloy, an indium-silver alloy, a lithium-aluminum alloy, a lithium-magnesium alloy, a lithium-indium alloy, and a calcium-aluminum alloy.

The anode and the cathode may have a laminated structure of 2 or more layers.

[ use ]

The light-emitting element of the present embodiment can be suitably used as a light source for a backlight of a liquid crystal display device, a light source for illumination, an organic EL illumination, a display device (for example, an organic EL display or an organic EL television) such as a computer, a television, or a mobile terminal.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above embodiments.

Examples

The present invention will be described in further detail below with reference to examples, but the present invention is not limited to these examples.

In the examples, the number average molecular weight (Mn) of the polymer compound in terms of polystyrene and the weight average molecular weight (Mw) of the polymer compound in terms of polystyrene were determined by Size Exclusion Chromatography (SEC) described below using tetrahydrofuran as a mobile phase.

The high molecular compound to be measured was dissolved in tetrahydrofuran at a concentration of about 0.05 mass%, and 10. mu.L was injected into SEC. The mobile phase was circulated at a flow rate of 1.0 mL/min. As the column, PLGel MIXED-B (manufactured by Polymer Laboratories) was used. As the detector, a UV-VIS detector (trade name: UV-8320GPC, manufactured by Tosoh corporation) was used.

Delta E for Compounds_STFor the calculation of the value (c), the ground state of the compound is structurally optimized by the density functional method at the B3LYP level, in which case 6-31G is used as the basis function. Then, using Gaussian09 as a quantum chemical computation program, Δ E of the compound was calculated by a time-dependent density functional method of B3LYP level_ST。

In the examples, the maximum peak wavelength of the emission spectrum of the compound at room temperature was measured by a spectrophotometer (FP-6500, manufactured by Nippon Kagaku Co., Ltd.) at room temperature. The compound is dissolved in xylene at about 8X 10^-4A xylene solution dissolved at a concentration of mass% was used as a sample. As the excitation light, Ultraviolet (UV) light having a wavelength of 325nm was used.

< Synthesis example M1 > Synthesis of Compounds M1 to M6

Compound M1 was synthesized according to the method described in International publication No. 2015/145871.

Compound M2 was synthesized according to the method described in International publication No. 2013/146806.

Compound M3 was synthesized according to the method described in International publication No. 2005/049546.

Compound M4 was synthesized according to the method described in Japanese patent application laid-open No. 2010-189630.

Compound M5 and compound M6 were synthesized according to the method described in International publication No. 2013/191088.

[ chemical formula 22]

< Synthesis example HTL-1 > Synthesis of high molecular Compound HTL-1

The high molecular weight compound HTL-1 was synthesized using compound M1, compound M2, and compound M3 according to the method described in International publication No. 2015/145871And (4) obtaining. Mn of Polymer HTL-1 was 2.3X 10⁴Mw of 1.2X 10⁵。

The molecular compound HTL-1 was a polymer obtained from the charged raw materials in a theoretical amount of 45: 5: a copolymer having a structural unit derived from the compound M1, a structural unit derived from the compound M2, and a structural unit derived from the compound M3 at a molar ratio of 50.

< Synthesis example HP1 > Synthesis of Polymer HP-1

The polymer compound HP-1 was synthesized by the method described in International publication No. 2015/008851 using Compound M4, Compound M5 and Compound M6. Mn of the high molecular compound HP-2 was 8.5X 10⁴Mw of 2.2X 10⁵。

The molecular compound HP-1 was a molecular weight ratio of 50: 26: 24 has a structural unit derived from compound M4, a structural unit derived from compound M5 and a structural unit derived from compound M6.

< obtaining and Synthesis of Compounds H1-H8, B1-B2 and Polymer PVK >

Compounds H1 to H7 were prepared from Luminescense Technology, Inc.

The compound H8 was synthesized according to the method described in Japanese patent application laid-open No. 2010-031259.

Poly (9-vinylcarbazole) (polymeric compound PVK) was prepared using Sigma-Aldrich (weight average molecular weight: 1.1X 10)⁶Powder, etc.).

Compound B1 and compound B2 were synthesized according to the method described in international publication No. 2015/102118.

[ chemical formula 23]

[ chemical formula 24]

[ chemical formula 25]

The maximum peak wavelength of the room-temperature emission spectrum of compound B1 was 453 nm. The half-value width of the maximum peak of the room-temperature emission spectrum of Compound B1 was 22 nm. Delta E of Compound B1_STIs 0.457 eV.

The maximum peak wavelength of the room-temperature emission spectrum of compound B2 was 467 nm. The half-value width of the maximum peak of the room-temperature emission spectrum of compound B2 was 20 nm. Delta E of Compound B2_STIs 0.457 eV.

< example D1 > production and evaluation of light-emitting element D1

(formation of Anode and hole-injecting layer)

An anode was formed by applying an ITO film to a glass substrate by a sputtering method to a thickness of 45 nm. On the anode, ND-3202 (manufactured by Nissan chemical industry) as a hole injection material was formed in a thickness of 35nm by spin coating. The substrate on which the hole injection layer was laminated was heated on a hot plate at 50 ℃ for 3 minutes and further at 230 ℃ for 15 minutes in an atmospheric atmosphere, thereby forming a hole injection layer.

(formation of hole transport layer)

The high molecular compound HTL-1 was dissolved in xylene at a concentration of 0.7 mass%. Using the obtained xylene solution, a film was formed on the hole injection layer by spin coating at a thickness of 20nm, and heated on a hot plate at 180 ℃ for 60 minutes under a nitrogen atmosphere, thereby forming a hole transport layer.

(formation of luminescent layer)

The polymer compound HP-1, the compound H2, and the compound B1 (polymer compound HP-1/compound H2/compound B1 ═ 94 mass%/5 mass%/1 mass%) were dissolved in toluene at a concentration of 2 mass%. The obtained toluene solution was used to form a film on the hole transport layer by spin coating at a thickness of 60nm, and the film was heated at 130 ℃ for 10 minutes in a nitrogen atmosphere, thereby forming a light-emitting layer.

(formation of cathode)

The substrate with the light emitting layer was reduced in pressure to 1.0X 10 in a deposition machine^-4After Pa or less, sodium fluoride was deposited on the light-emitting layer by about 4nm as a cathode, and then aluminum was deposited on the sodium fluoride layer by about 80 nm. After the vapor deposition, the substrate on which the cathode was formed was sealed with a glass substrate, thereby producing a light-emitting element D1.

(evaluation of light-emitting element)

EL emission was observed by applying a voltage to the light-emitting element D1. Measurement of 0.2mA/cm²External quantum efficiency [% ]]。

< examples D2 to D16 and comparative example CD1 > production and evaluation of light-emitting elements D2 to D16 and CD1

Light-emitting elements D2 to D16 and CD1 were produced in the same manner as in example D1, except that the materials described in table 2 were used instead of "polymer compound HP-1, compound H2 and compound B1" (polymer compound HP-1/compound H2/compound B1 is 94% by mass/5% by mass/1% by mass) "in example D1 (formation of a light-emitting layer).

EL emission was observed by applying a voltage to the light-emitting elements D2 to D16 and CD 1. Measurement of 0.2mA/cm²External quantum efficiency [% ]]。

The results of examples D1-D16 and comparative example CD1 are shown in Table 2. The relative values of the external quantum efficiencies of the light-emitting elements D1 to D16 are shown when the external quantum efficiency of the light-emitting element CD1 is 1.0.

[ Table 2]

Industrial applicability

The composition of the present invention is useful for producing a light-emitting element having excellent external quantum efficiency.