WO2023112808A1

WO2023112808A1 - Compound, host material, electron barrier material, composition and organic light emitting element

Info

Publication number: WO2023112808A1
Application number: PCT/JP2022/045210
Authority: WO
Inventors: 寛晃小澤; 貴弘柏▲崎▼; 亜衣子後藤; 京森本; ソンヘファン; ユバラズ凱令; 幸誠金原
Original assignee: 株式会社Kyulux
Priority date: 2021-12-17
Filing date: 2022-12-08
Publication date: 2023-06-22

Abstract

The present invention is able to provide an organic light emitting element having excellent characteristics by using a compound of the general formula in the organic light emitting element. In the general formula, R1 to R4 and R8 to R19 each represent a hydrogen atom, a deuterium atom, an alkyl group or an aryl group; R5 to R7 each represent a hydrogen atom, a deuterium atom or an alkyl group; and at least one of R1 to R4 represents an alkyl group or an aryl group.

Description

Compounds, host materials, electron barrier materials, compositions and organic light-emitting devices

The present invention relates to compounds useful as host materials, electron barrier materials, etc., and compositions and organic light-emitting devices using the compounds.

Research and development of materials used for organic light-emitting devices such as organic electroluminescence devices (organic EL devices) have been actively carried out. In particular, various attempts have been made to improve the characteristics of the device by newly developing and combining electron-transporting materials, hole-transporting materials, light-emitting materials, host materials, and the like, which constitute organic electroluminescence devices. For example, as host materials, mCBP and mCP having the following structures have been widely recognized as useful host materials.

In addition to these compounds having a carbazole structure, compounds having both a carbazole structure and a dibenzofuran structure have also been proposed (see Patent Document 1).

WO2021/157593

However, even if a host material that has been used conventionally is used, it may not always be possible to provide a light-emitting device having excellent characteristics. For example, when combined with a delayed fluorescence material, it is often not possible to produce an organic light-emitting device with excellent properties even if a useful host material is used as it is. In particular, when used in organic electroluminescence devices, there is room for improvement in terms of drive voltage and device life. Therefore, the present inventors have made studies with the aim of improving the characteristics of the organic light-emitting device by providing an excellent host material.

As a result of intensive studies, the present inventors found that the characteristics can be improved by using a compound having a specific structure in an organic light-emitting device. The present invention has been proposed based on these findings, and specifically has the following configurations.

[1] A compound represented by the following general formula (1).

[In the general formula (1),
R ¹ to R ⁴ and R ⁸ to R ¹⁹ each independently represent a hydrogen atom, a deuterium atom, a substituted or unsubstituted aryl group, or a substituted or unsubstituted alkyl group;
R ⁵ to R ⁷ each independently represent a hydrogen atom, a deuterium atom, or a substituted or unsubstituted alkyl group;
at least one of R ¹ to R ⁴ is a substituted or unsubstituted aryl group or a substituted or unsubstituted alkyl group;
R ¹² and R ¹³ , R ¹³ and R ¹⁴ , R ¹⁴ and R ¹⁵ , R ¹⁶ and R ¹⁷ , R ¹⁷ and R ¹⁸ , R ¹⁸ and R ¹⁹ may combine with each other to form a cyclic structure. . ]
[2] R ¹ to R ⁴ and R ⁸ to R ¹⁹ each independently represent one or more atoms or groups selected from the group consisting of hydrogen atoms, deuterium atoms, alkyl groups and aryl groups; The compound according to [1], which is a group that can be combined.
[3] at least one of R ¹ to R ⁴ may be substituted with one atom or group selected from the group consisting of a deuterium atom, an alkyl group and an aryl group, or a group formed by combining two or more; The compound according to [1] or [2], which is a good aryl group.
[4] The compound according to any one of [1] to [3], wherein R ² is a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group.
[5] The compound according to any one of [1] to [4], wherein at least one of R ¹⁴ and R ¹⁷ is a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group.
[6] The compound according to any one of [1] to [5], wherein the total number of benzene rings contained in R ¹ to R ¹⁹ is 1 to 3.
[7] The compound according to any one of [1] to [6], wherein R ⁵ to R ⁷ are each independently a hydrogen atom or a deuterium atom.
[8] at least one pair of R ¹² and R ¹³ , R ¹³ and R ¹⁴ , R ¹⁴ and R ¹⁵ , R ¹⁶ and R ¹⁷ , R ¹⁷ and R ¹⁸ , R ¹⁸ and R ¹⁹ are bonded to each other; The compound according to any one of [1] to [7], which forms a cyclic structure.
[9] A host material containing the compound according to any one of [1] to [8].
[10] The host material of [9] for use with a delayed fluorescence material.
[11] An electron barrier material containing the compound according to any one of [1] to [8].
[12] A composition obtained by doping the compound according to any one of [1] to [8] with a delayed fluorescence material.
[13] The composition according to [12], which is in the form of a film.
[14] The composition according to [12] or [13], wherein the delayed fluorescence material is a compound having a cyanobenzene structure in which the benzene ring is substituted with one cyano group.
[15] The composition according to [14], wherein the delayed fluorescence material has two or more substituted or unsubstituted carbazolyl groups bonded to the benzene ring in addition to the cyano group.
[16] The composition according to [12] or [13], wherein the delayed fluorescence material is a compound having a dicyanobenzene structure in which the benzene ring is substituted with two cyano groups.
[17] Any one of [14] to [16], further comprising a fluorescent compound having a lower lowest excited singlet energy than the compound represented by the general formula (1) and the delayed fluorescent material. Composition.
[18] The composition according to any one of [12] to [17], further comprising a host material not represented by general formula (1).
[19] An organic light emitting device comprising the compound according to any one of [1] to [8].
[20] An organic light-emitting device having a layer made of the composition described in [12].
[21] The organic light emitting device according to [20], wherein the layer consists only of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms, oxygen atoms, boron atoms and halogen atoms.
[22] The organic light emitting device according to [21], wherein the layer consists only of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms and oxygen atoms.
[23] The organic light emitting device according to any one of [19] to [22], which is an organic electroluminescence device.

By using the compound of the present invention, an organic light-emitting device with excellent characteristics can be provided. For example, organic light-emitting devices using the compound of the present invention include organic light-emitting devices with low driving voltage and organic light-emitting devices with long device life.

The contents of the present invention will be described in detail below. The constituent elements described below may be explained based on representative embodiments and specific examples of the present invention, but the present invention is not limited to such embodiments and specific examples. In this specification, the numerical range represented by "-" means a range including the numerical values before and after "-" as lower and upper limits. Further, the isotopic species of the hydrogen atom present in the molecule of the compound used in the present invention is not particularly limited.

(Compound represented by general formula (1))
In the present invention, a compound represented by the following general formula (1) is used.

In general formula (1), R ¹ to R ⁴ and R ⁸ to R ¹⁹ each independently represent a hydrogen atom, a deuterium atom, a substituted or unsubstituted aryl group, or a substituted or unsubstituted alkyl group. Preferably, R ¹ -R ⁴ and R ⁸ -R ¹⁹ are each independently a hydrogen atom or one or two atoms or groups selected from the group consisting of a deuterium atom, an alkyl group and an aryl group. It is a group formed by combining two or more. In general formula (1), at least one of R ¹ to R ⁴ is a substituted or unsubstituted aryl group or a substituted or unsubstituted alkyl group. Preferably, at least one of R ¹ to R ⁴ is an aryl group, which has one or more atoms or groups selected from the group consisting of deuterium atoms, alkyl groups and aryl groups. It may be substituted with a group that can be combined. In general formula (1), R ⁵ to R ⁷ each independently represent a hydrogen atom, a deuterium atom, or a substituted or unsubstituted alkyl group.

In one aspect of the invention, at least one of R ¹ to R ⁴ is a substituted or unsubstituted aryl group, for example only one is a substituted or unsubstituted aryl group and only two are substituted or unsubstituted is an aryl group of In one aspect of the invention, R ¹ is a substituted or unsubstituted aryl group. In one preferred aspect of the invention, R ² is a substituted or unsubstituted aryl group. In one aspect of the invention, R ³ is a substituted or unsubstituted aryl group. In one aspect of the invention, ^R4 is a substituted or unsubstituted aryl group. In one aspect of the present invention, each of R ¹ -R ⁴ is independently a hydrogen atom, a deuterium atom, or a substituted or unsubstituted aryl group.
In one aspect of the invention, at least one of R ¹ to R ⁴ is a substituted or unsubstituted alkyl group, for example only one is a substituted or unsubstituted alkyl group and only two are substituted or unsubstituted is an alkyl group of In one aspect of the invention, R ¹ is a substituted or unsubstituted alkyl group. In one preferred aspect of the invention, R ² is a substituted or unsubstituted alkyl group. In one aspect of the invention, R ³ is a substituted or unsubstituted alkyl group. In one aspect of the invention, ^R4 is a substituted or unsubstituted alkyl group. In one aspect of the present invention, each of R ¹ to R ⁴ is independently a hydrogen atom, a deuterium atom, or a substituted or unsubstituted alkyl group.

In a preferred embodiment of the present invention, each of R ⁵ to R ⁷ is independently hydrogen or deuterium. In one aspect of the invention, at least one of R ⁵ to R ⁷ is a substituted or unsubstituted alkyl group. For example, all of R ⁵ to R ⁷ are each independently substituted or unsubstituted alkyl groups. In one aspect of the invention, ^R5 is a substituted or unsubstituted alkyl group. In one aspect of the invention, ^R6 is a substituted or unsubstituted alkyl group. In one aspect of the invention, ^R7 is a substituted or unsubstituted alkyl group.

In a preferred embodiment of the present invention, each of R ⁸ to R ¹¹ is independently a hydrogen atom or a deuterium atom. In one aspect of the invention, at least one of R ⁸ to R ¹¹ is a substituted or unsubstituted aryl group. In one aspect of the invention, R ⁸ is a substituted or unsubstituted aryl group. In one aspect of the invention, ^R9 is a substituted or unsubstituted aryl group. In one aspect of the invention, at least one of R ⁸ to R ¹¹ is a substituted or unsubstituted alkyl group. In one aspect of the invention, R ¹⁰ is a substituted or unsubstituted alkyl group. In one aspect of the invention, R ¹¹ is a substituted or unsubstituted alkyl group.

In one aspect of the invention, R ¹² -R ¹⁹ are each independently a hydrogen atom or a deuterium atom. In one aspect of the invention, at least one of R ¹² -R ¹⁹ is a deuterium atom, eg all are deuterium atoms. In one aspect of the invention, at least one of R ¹² to R ¹⁹ is a substituted or unsubstituted aryl group. In one aspect of the invention, only one of R ¹² to R ¹⁹ is a substituted or unsubstituted aryl group. In one aspect of the invention, only two of R ¹² to R ¹⁹ are substituted or unsubstituted aryl groups. In one aspect of the present invention, only one of R ¹² to R ¹⁵ and only one of R ¹⁶ to R ¹⁹ are each independently a substituted or unsubstituted aryl group. In one aspect of the invention, R ¹² is a substituted or unsubstituted aryl group. In one aspect of the invention, R ¹³ is a substituted or unsubstituted aryl group. In a preferred aspect of the invention, R ¹⁴ is a substituted or unsubstituted aryl group. In one aspect of the invention, R ¹⁵ is a substituted or unsubstituted aryl group.
In one aspect of the invention, at least one of R ¹² to R ¹⁹ is a substituted or unsubstituted alkyl group. In one aspect of the present invention, at least one of R ¹² to R ¹⁵ and at least one of R ¹⁶ to R ¹⁹ are each independently a substituted or unsubstituted alkyl group. In one aspect of the invention, R ¹⁶ is a substituted or unsubstituted alkyl group. In one aspect of the invention, R ¹⁷ is a substituted or unsubstituted alkyl group. In one preferred aspect of the invention, R ¹⁸ is a substituted or unsubstituted alkyl group. In one aspect of the invention, R ¹⁹ is a substituted or unsubstituted alkyl group.
In a preferred embodiment of the present invention, R ¹⁴ is a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group, more preferably a substituted or unsubstituted aryl group, and for example R ¹² , R ¹³ , R ¹⁵ to R ¹⁹ are each independently a hydrogen atom or a deuterium atom. In a preferred embodiment of the present invention, R ¹⁴ and R ¹⁷ are each independently a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group, more preferably each independently a substituted or unsubstituted aryl group. and, for example, R ¹² , R ¹³ , R ¹⁵ , R ¹⁶ , R ¹⁸ and R ¹⁹ are each independently a hydrogen atom or a deuterium atom. In one aspect of the invention, R ¹⁴ and R ¹⁷ are the same. In one aspect of the invention, R ¹⁴ and R ¹⁷ are different.

In the present invention, the total number of benzene rings contained in R ¹ to R ¹⁹ is preferably 1 to 10, more preferably 1 to 6, still more preferably 1 to 4, for example 1. , for example 2, for example 3. The total number of substituted or unsubstituted aryl groups in R ¹ to R ¹⁹ is preferably 1 to 8, more preferably 1 to 4, such as 1, such as 2, such as 3. .
In a preferred embodiment of the present invention, R ¹ -R ⁴ and R ⁸ -R ¹⁹ are each independently a hydrogen atom, a deuterium atom, or a substituted or unsubstituted aryl group. In a preferred embodiment of the present invention, R ² is a substituted or unsubstituted aryl group, R ¹⁴ is a substituted or unsubstituted aryl group or a substituted or unsubstituted alkyl group, R ¹⁷ is a hydrogen atom, a heavy a hydrogen atom, a substituted or unsubstituted aryl group, ^or a substituted or unsubstituted alkyl group; R ¹ , R ³ to R 13 , R ¹⁵ , R ¹⁶ , R ¹⁸ , and R ¹⁹ It is a hydrogen atom.

When the aryl group that can be taken by R ¹ to R ⁴ and R ⁸ to R ¹⁹ is substituted, it is an aryl group substituted with a deuterium atom, an aryl group substituted with an alkyl group, or an aryl group It is preferably an aryl group substituted with. The aryl group that can be taken by R ¹ to R ⁴ and R ⁸ to R ¹⁹ is substituted with one atom or group selected from the group consisting of a deuterium atom and an aryl group, or a group formed by combining two or more more preferably an aryl group with a For example, it is an aryl group optionally substituted with a deuterium atom.
When the alkyl group that R ¹ to R ¹⁹ can take is substituted, it is preferably an alkyl group substituted with a deuterium atom or an alkyl group substituted with an aryl group. The alkyl group that can be taken by R ¹ to R ¹⁹ is more preferably an alkyl group optionally substituted with a deuterium atom.
The "alkyl group" in the present application may be linear, branched or cyclic. Moreover, two or more of the linear portion, the cyclic portion and the branched portion may be mixed. The number of carbon atoms in the alkyl group can be, for example, 1 or more, 2 or more, or 4 or more. Also, the number of carbon atoms can be 30 or less, 20 or less, 10 or less, 6 or less, or 4 or less. Specific examples of alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, n-hexyl, cyclopentyl, A cyclohexyl group and a cycloheptyl group can be mentioned. In one aspect of the invention, the alkyl group has 1 to 4 carbon atoms. In one aspect of the invention, the alkyl group is a methyl group. In one aspect of the invention, the alkyl group is an isopropyl group. In one aspect of the invention, the alkyl group is a tert-butyl group. When multiple alkyl groups are present in the molecule represented by formula (1), the alkyl groups may be the same or different. In one aspect of the present invention, all alkyl groups in the molecule represented by general formula (1) are the same. The number of alkyl groups in the molecule represented by general formula (1) can be 0 or more, 1 or more, 2 or more, 4 or more, and 8 or more. The number of alkyl groups in the molecule represented by formula (1) may be 20 or less, 10 or less, 5 or less, or 3 or less. The number of alkyl groups in the molecule represented by general formula (1) may be zero.
The "alkyl group optionally substituted with a deuterium atom" in the present application means that at least one hydrogen atom of the alkyl group may be substituted with a deuterium atom. All hydrogen atoms in the alkyl group may be replaced with deuterium atoms. For example, optionally deuterated methyl groups include _CH3 , _CDH2 , _CD2H , _CD3 . The "optionally deuterated alkyl group" is preferably an alkyl group that is not deuterated at all or an alkyl group in which all hydrogen atoms are substituted with deuterium atoms. In one aspect of the present invention, an alkyl group that is not deuterated at all is selected as the "optionally deuterated alkyl group". In one aspect of the present invention, an alkyl group in which all hydrogen atoms are substituted with deuterium atoms is selected as the "optionally deuterated alkyl group". In one aspect of the present invention, the "optionally deuterated alkyl group" is a non-deuterated methyl group [--CH ₃ ], a non-deuterated ethyl group [--CH ₂ CH ₃ ] , non-deuterated isopropyl group [--CH(CH ₃ ) ₂ ], non-deuterated tert-butyl group [--C(CH ₃ ) ₃ ] or all hydrogen atoms deuterated methyl It is the group [-CD ₃ ]. In one aspect of the present invention, an “optionally deuterated alkyl group” is a methyl group that is not deuterated [—CH ₃ ] or a methyl group in which all hydrogen atoms are deuterated [—CD ₃ ]. In one aspect of the present invention, at least one alkyl group having at least one hydrogen atom substituted with a deuterium atom is present in the molecule represented by general formula (1).

An "aryl group" may be a monocyclic ring or a condensed ring in which two or more rings are condensed. When monocyclic, the aryl group is a phenyl group. When it is a condensed ring, the aryl group is a group in which one or more rings are further condensed to the phenyl group. The ring condensed to the phenyl group may be an aromatic hydrocarbon ring, an aromatic heterocyclic ring, an aliphatic hydrocarbon ring, or an aliphatic heterocyclic ring, or a ring in which these are condensed. Preferred are aromatic hydrocarbon rings and aromatic heterocycles. A benzene ring can be mentioned as an aromatic hydrocarbon ring. The benzene ring may be condensed with another benzene ring, or may be condensed with a heterocyclic ring such as a pyridine ring. The aromatic heterocyclic ring means an aromatic ring containing a heteroatom as a ring skeleton-constituting atom, and is preferably a 5- to 7-membered ring, such as a 5-membered ring or a 6-membered ring. can be adopted. In one aspect of the present invention, a furan ring, a thiophene ring, or a pyrrole ring can be employed as the aromatic heterocyclic ring.
Specific examples of rings that constitute the aryl group include a benzene ring and a naphthalene ring. Specific examples of aryl groups include phenyl, naphthalene-1-yl and naphthalene-2-yl groups. These groups given as specific examples may be substituted.
The "aryl group optionally substituted with a deuterium atom" in the present application means that at least one hydrogen atom of the aryl group may be substituted with a deuterium atom. All of the hydrogen atoms in the aryl group may be replaced with deuterium atoms. For example, _optionally deuterated _phenyl groups _include _C6H5 _, _C6H4D , _C6H3D2 _, _C6H2D3 _, _C6HD4 _, _C6D5 _. included. The "optionally deuterated aryl group" is preferably an aryl group that is not deuterated at all or an aryl group in which all hydrogen atoms are substituted with deuterium atoms. In one aspect of the present invention, an aryl group that is not deuterated at all is selected as the "optionally deuterated aryl group". In one aspect of the present invention, an aryl group in which all hydrogen atoms are substituted with deuterium atoms is selected as the “optionally deuterated aryl group”. In one aspect of the present invention, the “optionally deuterated aryl group” is a non-deuterated phenyl group [—C ₆ H ₅ ], a non-deuterated naphthyl group [—C ₁₀ H ₇ ], a phenyl group in which all hydrogen atoms are deuterated [--C ₆ D ₅ ], and a naphthyl group in which all hydrogen atoms are deuterated [--C ₁₀ D ₇ ].

Specific examples of aryl groups that R ¹ to R ⁴ and R ⁸ to R ¹⁹ can take are given below. However, the aryl group that can be employed in the present invention is not limited to the following specific examples. In the following specific examples, * indicates the binding position. Moreover, the display of the methyl group is omitted. Therefore, Ar2 to Ar7 represent structures substituted with methyl groups.

In addition to the above specific examples, a group in which all the hydrogen atoms present in the alkyl groups that are substituents of Ar2 to Ar11 are substituted with deuterium atoms, and a benzene ring that is directly bonded to the bonding position * of Ar12 to Ar16. Groups obtained by substituting deuterium atoms for all hydrogen atoms present in the aryl group are exemplified here as Ar2(d) to Ar16(d) in order. Groups in which all hydrogen atoms present in Ar1 to Ar16 are substituted with deuterium atoms are exemplified here as Ar1(D) to Ar16(D) in order.
In one aspect of the present invention, the aryl group that R ¹ to R ⁴ and R ⁸ to R ¹⁹ can take is Ar1 or Ar1(D). In one aspect of the present invention, the aryl group that can be taken by R ¹ to R ⁴ and R ⁸ to R ¹⁹ is the group consisting of Ar2 to Ar11, Ar2(d) to Ar11(d) and Ar2(D) to Ar11(D) more selected. In one aspect of the present invention, the aryl group that can be taken by R ¹ to R ⁴ and R ⁸ to R ¹⁹ is the group consisting of Ar12 to Ar16, Ar12(d) to Ar16(d) and Ar12(D) to Ar16(D) more selected. In one aspect of the present invention, the aryl groups that R ¹ to R ⁴ and R ⁸ to R ¹⁹ can take are Ar1, Ar1(D), Ar12 to Ar16, Ar12(d) to Ar16(d) and Ar12(D) to is selected from the group consisting of Ar16(D);

R ¹² and R ¹³ , R ¹³ and R ¹⁴ , R ¹⁴ and R ¹⁵ , R ¹⁶ and R ¹⁷ , R ¹⁷ and R ¹⁸ , R ¹⁸ and R ¹⁹ in the general formula (1) are bonded to form a cyclic structure may be formed. R ¹ to R ¹¹ in general formula (1) do not form a cyclic structure by combining with nearby groups.
The cyclic structure may be an aromatic ring, a heteroaromatic ring, an aliphatic hydrocarbon ring, or an aliphatic heterocyclic ring, or a condensed ring thereof. Aromatic rings and heteroaromatic rings are preferred. Examples of aromatic rings include substituted or unsubstituted benzene rings. The heteroaromatic ring means an aromatic ring containing a heteroatom as a ring skeleton-constituting atom, and is preferably a 5- to 7-membered ring, such as a 5-membered ring or a 6-membered ring. can be adopted. In one aspect of the present invention, a furan ring, a thiophene ring, and a pyrrole ring can be employed as the heteroaromatic ring. A cyclopentadiene ring can be mentioned as an aliphatic hydrocarbon ring. In a preferred embodiment of the present invention, the cyclic structure is a benzene ring, a furan ring of substituted or unsubstituted benzofuran, a thiophene ring of substituted or unsubstituted benzothiophene, or a pyrrole ring of substituted or unsubstituted indole. In a preferred embodiment of the present invention, benzofuran, benzothiophene, and indole here are one atom or group selected from the group consisting of a deuterium atom, an alkyl group, and an aryl group, or a group formed by combining two or more. may be substituted. In one aspect of the invention, the benzofurans, benzothiophenes, and indoles referred to herein are unsubstituted.

In one aspect of the present invention, R ¹² and R ¹³ , R ¹³ and R ¹⁴ , R ¹⁴ and R ¹⁵ , R ¹⁶ and R ¹⁷ , R ¹⁷ and R ¹⁸ , R ¹⁸ and R ¹⁹ are bonded to each other to form a cyclic structure. The group (group having a carbazole structure) that is not formed and is bonded to the nitrogen atom on the right side of general formula (1) is a substituted or unsubstituted non-fused carbazol-9-yl group.
In one aspect of the present invention, one or more pairs of R ¹² and R ¹³ , R ¹³ and R ¹⁴ , R ¹⁴ and R ¹⁵ , R ¹⁶ and R 17 , R ¹⁷ and R ¹⁸ , ^{R 18} ^and R ¹⁹ (preferably ) are bonded to each other, and the groups bonded at the nitrogen atom on the right side of general formula (1) are benzofuro[2,3-a]carbazol-1-yl group, benzofuro[3,2-a]carbazole- 1-yl group, benzofuro[2,3-b]carbazol-1-yl group, benzofuro[3,2-b]carbazol-1-yl group, benzofuro[2,3-c]carbazol-1-yl group, Or it forms a benzofuro[3,2-c]carbazol-1-yl group. These groups may be substituted, and in one aspect of the present invention, substituted with one atom or group selected from the group consisting of a deuterium atom, an alkyl group and an aryl group, or a group formed by combining two or more may have been
In one aspect of the present invention, one or more pairs of R ¹² and R ¹³ , R ¹³ and R ¹⁴ , R ¹⁴ and R ¹⁵ , R ¹⁶ and R 17 , R ¹⁷ and R ¹⁸ , ^{R 18} ^and R ¹⁹ (preferably ) are bonded to each other, and the groups bonded at the nitrogen atoms on the right side of general formula (1) are benzothieno[2,3-a]carbazol-1-yl groups, benzothieno[3,2-a]carbazole- 1-yl group, benzothieno[2,3-b]carbazol-1-yl group, benzothieno[3,2-b]carbazol-1-yl group, benzothieno[2,3-c]carbazol-1-yl group, Or it forms a benzothieno[3,2-c]carbazol-1-yl group. These groups may be substituted, and in one aspect of the present invention, substituted with one atom or group selected from the group consisting of a deuterium atom, an alkyl group and an aryl group, or a group formed by combining two or more may have been

Specific examples of the groups (groups having a carbazole structure) bonded at the nitrogen atom on the right side of general formula (1) are given below. However, what can be employed in the present invention is not limitedly interpreted by the following specific examples. In the following specific examples, * indicates the bonding position to the central benzene ring in general formula (1). Ph represents a phenyl group. Moreover, the display of the methyl group is omitted. Therefore, for example, D2 to D6 represent structures substituted with methyl groups.

In addition to the above specific examples, groups in which all hydrogen atoms present in alkyl groups and phenyl groups as substituents of D2 to D20 and D33 to D262 are substituted with deuterium atoms are exemplified here as D263 to D511. . Further, groups in which all hydrogen atoms existing in D1 to D262 are replaced with deuterium atoms are exemplified here as D512 to D773 in order.
In one aspect of the present invention, the group bonded to the nitrogen atom on the right side of general formula (1) (group having a carbazole structure) is selected from D1 to D773. In one aspect of the present invention, the group attached to the nitrogen atom on the right side of general formula (1) is D1 or D512. In one aspect of the present invention, the groups bonded at the nitrogen atom on the right side of general formula (1) are selected from D1, D21-D32, D512, D532-D543. In one aspect of the present invention, the groups bonded at the nitrogen atom on the right side of general formula (1) are selected from D1-D14, D263-D275 and D512-D525. In one aspect of the present invention, the groups bonded at the nitrogen atom on the right side of general formula (1) are selected from D2-D14, D263-D275 and D513-D525. In one aspect of the present invention, the groups bonded at the nitrogen atom on the right side of general formula (1) are selected from D1, D15-D20, D33-D237, D276-D486, D512, D526-D531, D544-D748. . In one aspect of the present invention, the groups bonded at the nitrogen atom on the right side of general formula (1) are selected from D15-D20, D33-D237, D276-D486, D526-D531, D544-D748. In one aspect of the present invention, the groups bonded at the nitrogen atom on the right side of general formula (1) are selected from D1-D20, D263-D281 and D512-D531. In one aspect of the present invention, the groups bonded at the nitrogen atom on the right side of general formula (1) are selected from D21-D237, D282-D486, and D532-D748.

Specific examples of the group having a tricyclic structure (substituted dibenzofuran-2-yl group) on the left side of general formula (1) are given below. However, what can be employed in the present invention is not limitedly interpreted by the following specific examples. In the following specific examples, * indicates the bonding position to the central benzene ring in general formula (1). Moreover, the display of the methyl group is omitted. Therefore, Z13 to Z24, for example, represent structures substituted with methyl groups.

In addition to the above specific examples, groups in which all hydrogen atoms of Z1 to Z40 are deuterated are exemplified here as Z41 to Z80, respectively. Groups in which all the hydrogen atoms of the phenyl groups (C ₆ H ₅ ) of Z1 to Z4 and Z13 to Z16 are substituted with deuterated C ₆ _D5 are exemplified here as Z81 to Z88, respectively. Furthermore, groups obtained by deuterating all the hydrogen atoms of the methyl group, isopropyl group and tert-butyl group of Z17 to Z40 are exemplified here as Z89 to Z112, respectively.

In one aspect of the present invention, the group having a tricyclic structure (substituted dibenzofuran-2-yl group) on the left side of general formula (1) is selected from Z1 to Z112. In one aspect of the present invention, the group having a tricyclic structure on the left side of general formula (1) is selected from Z1-Z28, Z41-Z68 and Z81-Z100.

The compound represented by general formula (1) does not contain a metal element. In one aspect of the present invention, the compound represented by general formula (1) consists only of atoms selected from the group consisting of carbon atoms, hydrogen atoms, deuterium atoms, nitrogen atoms, oxygen atoms and sulfur atoms. In one aspect of the present invention, the compound represented by general formula (1) consists only of atoms selected from the group consisting of carbon atoms, hydrogen atoms, deuterium atoms, oxygen atoms and nitrogen atoms.
The molecular weight of the compound represented by formula (1) is preferably 1500 or less, more preferably 1200 or less, and even more preferably 800 or less. For example, it may be selected within the range of 700 or less, may be selected within the range of 600 or less, or may be selected within the range of 550 or less. The lower limit of the molecular weight is the minimum molecular weight of the structure represented by general formula (1).

A preferred group of compounds represented by the general formula (1) includes compounds represented by the following general formula (2). For definitions, explanations and preferred ranges of R ¹ to R ⁴ and R ¹² to R ¹⁹ in general formula (2), the corresponding descriptions in general formula (1) can be referred to.

A preferred group of compounds represented by the general formula (1) includes compounds represented by the following general formula (3). For definitions, explanations and preferred ranges of R ¹ , R ³ to R ¹⁹ in general formula (3), the corresponding descriptions in general formula (1) can be referred to. R ²⁰ to R ²⁴ each independently represent a hydrogen atom, a deuterium atom, a substituted or unsubstituted aryl group, or a substituted or unsubstituted alkyl group. The preferred range of R ²⁰ to R ²⁴ can be referred to the description of R ⁸ to R ¹⁰ in formula (1).

Specific examples of the compound represented by formula (1) are given below. Specific examples are illustrated by identifying Z and D in the general formula below in the table. In addition, the compound represented by the general formula (1) that can be used in the present invention is not limitedly interpreted by these specific examples.
Table 1 individually identifies the structures of compounds 1-1546 where Z and D are the groups described in each row of the table.

Table 2 identifies each structure of compounds 1-86576 by defining Z and D in each structure. Each row of Table 2 identifies, in order, 773 compounds with Z fixed and D varied from D1 to D773. Compounds 1-1546 of Table 2 identify the same as compounds 1-1546 of Table 1.

Compounds in which all hydrogen atoms in compounds 1 to 86576 are replaced with deuterium atoms are exemplified as compounds 1(D) to 86576(D) in order.
In one aspect of the present invention, compounds are selected from Compounds 1-86576 and Compounds 1(D)-86576(D). In one aspect of the present invention, the Select a compound from among In one aspect of the present invention, a compound selected from compounds 30921-52564, 61841-77300, 1(D)-21644(D), 30921(D)-52564(D), 61841(D)-77300(D) select.

An example of a preferred group of compounds represented by general formula (1) is shown below.

An example of another preferred group of compounds represented by general formula (1) is given below.

A compound represented by the general formula (1) is useful as a host material for doping a light-emitting material. It is particularly useful as a host material for doping a delayed fluorescence material. The material to be doped may be not only one kind but also plural kinds. A material to be doped is selected from those having a lowest excited singlet energy lower than that of the compound represented by the general formula (1).
The compound represented by general formula (1) is also useful as a carrier-blocking material, such as an electron-blocking material. It can be effectively used as a barrier layer (for example, an electron barrier layer) in an organic light-emitting device such as an organic electroluminescence device.

(delayed fluorescence material)
A compound represented by the general formula (1) is useful as a host material for use with a delayed fluorescence material.
The term "delayed fluorescence material" as used herein means that in an excited state, reverse intersystem crossing occurs from an excited triplet state to an excited singlet state, and delayed fluorescence is emitted when returning from the excited singlet state to the ground state. It is an organic compound. In the present invention, a delayed fluorescence material is defined as a material that emits fluorescence with an emission lifetime of 100 ns (nanoseconds) or more when measured by a fluorescence lifetime measurement system (such as a streak camera system manufactured by Hamamatsu Photonics).
When the compound represented by the general formula (1) and the delayed fluorescence material are used in combination, the delayed fluorescence material receives energy from the compound represented by the general formula (1) in an excited singlet state to an excited singlet state transition to Further, the delayed fluorescence material may receive energy from the compound represented by general formula (1) in the excited triplet state and transition to the excited triplet state. Since the delayed fluorescent material has a small difference ( _ΔEST ) between the excited singlet energy and the excited triplet energy, the delayed fluorescent material in the excited triplet state easily undergoes reverse intersystem crossing to the delayed fluorescent material in the excited singlet state. The delayed fluorescent material in the excited singlet state generated by these pathways contributes to light emission.

In the delayed fluorescence material, the difference _ΔEST between the lowest excited singlet energy and the lowest excited triplet energy at 77K is preferably 0.3 eV or less, more preferably 0.25 eV or less, and 0.2 eV or less. is more preferably 0.15 eV or less, more preferably 0.1 eV or less, even more preferably 0.07 eV or less, and even more preferably 0.05 eV or less , is more preferably 0.03 eV or less, and particularly preferably 0.01 eV or less.
If _ΔEST is small, reverse intersystem crossing from the excited singlet state to the excited triplet state is likely to occur due to the absorption of thermal energy, and thus the material functions as a thermally activated delayed fluorescence material. A thermally activated delayed fluorescence material absorbs the heat emitted by the device and relatively easily undergoes reverse intersystem crossing from the excited triplet state to the excited singlet state, and efficiently contributes the excited triplet energy to light emission. can be done.

The lowest excited singlet energy (E _S1 ) and the lowest excited triplet energy (E _T1 ) of the compound in the present invention are values determined by the following procedure. ΔE _ST is a value obtained by calculating E _S1 -E _T1 .
(1) Lowest excited singlet energy (E _S1 )
A thin film or a toluene solution (concentration 10 ⁻⁵ mol/L) of the compound to be measured is prepared and used as a sample. The fluorescence spectrum of this sample is measured at room temperature (300K). In the fluorescence spectrum, the vertical axis is light emission and the horizontal axis is wavelength. A tangent line is drawn to the rise on the short wave side of the emission spectrum, and the wavelength value λedge [nm] at the intersection of the tangent line and the horizontal axis is obtained. A value obtained by converting this wavelength value into an energy value using the following conversion formula is assumed to be _ES1 .
Conversion formula: E _S1 [eV]=1239.85/λedge
The emission spectra in the examples described later were measured using an LED light source (Thorlabs, M300L4) as an excitation light source and a detector (Hamamatsu Photonics, PMA-12 multichannel spectrometer C10027-01).
(2) lowest excited triplet energy (E _T1 )
The same sample used in the measurement of the lowest excited singlet energy (E _S1 ) is cooled to 77 [K] with liquid nitrogen, the sample for phosphorescence measurement is irradiated with excitation light (300 nm), and a detector is used to Measure phosphorescence. Emission after 100 milliseconds from irradiation with excitation light is defined as a phosphorescence spectrum. A tangent line is drawn to the rising edge of the phosphorescence spectrum on the short wavelength side, and the wavelength value λedge [nm] at the intersection of the tangent line and the horizontal axis is obtained. A value obtained by converting this wavelength value into an energy value using the following conversion formula is defined as _ET1 .
Conversion formula: E _T1 [eV]=1239.85/λedge
A tangent line to the rise on the short wavelength side of the phosphorescence spectrum is drawn as follows. When moving on the spectrum curve from the short wavelength side of the phosphorescence spectrum to the maximum value on the shortest wavelength side among the maximum values of the spectrum, consider the tangent line at each point on the curve toward the long wavelength side. This tangent line increases in slope as the curve rises (ie as the vertical axis increases). The tangent line drawn at the point where the value of this slope takes the maximum value is taken as the tangent line to the rise on the short wavelength side of the phosphorescence spectrum.
In addition, the maximum point with a peak intensity of 10% or less of the maximum peak intensity of the spectrum is not included in the maximum value on the shortest wavelength side described above, and is closest to the maximum value on the short wavelength side. The tangent line drawn at the point where the value is taken is taken as the tangent line to the rise on the short wavelength side of the phosphorescence spectrum.

In a preferred embodiment of the present invention, a compound (cyanobenzene derivative) having a cyanobenzene structure in which the benzene ring is substituted with one cyano group is used as the delayed fluorescence material. In another preferred embodiment of the present invention, a compound (dicyanobenzene derivative) having a dicyanobenzene structure in which two cyano groups are substituted on the benzene ring is used as the delayed fluorescence material. In another preferred embodiment of the present invention, a compound (azabenzene derivative) having an azabenzene structure in which at least one carbon atom constituting the ring skeleton of a benzene ring is substituted with a nitrogen atom is used as the delayed fluorescence material.

In a preferred embodiment of the present invention, a compound represented by the following general formula (4) is used as the delayed fluorescence material.

In general formula (4), one of R ²¹ to R ²³ represents a cyano group or a group represented by general formula (5) below, and the remaining two of R ²¹ to R ²³ and R ²⁴ and R ²⁵ At least one of them represents a group represented by the following general formula (6), and the rest of R ²¹ to R ²⁵ are hydrogen atoms or substituents (wherein the substituent here is a cyano group, the following general formula (5) is not a group represented by the following general formula (6)).

In general formula (5), ^L1 represents a single bond or a divalent linking group, ^R31 and ^R32 each independently represent a hydrogen atom or a substituent, and * represents a bonding position.

In general formula (6), ^L2 represents a single bond or a divalent linking group, ^R33 and ^R34 each independently represent a hydrogen atom or a substituent, and * represents a bonding position.

In one preferred aspect of the invention, R ²² is a cyano group. In a preferred embodiment of the present invention, R ²² is a group represented by general formula (5). In one aspect of the present invention, R ²¹ is a cyano group or a group represented by general formula (5). In one aspect of the present invention, R ²³ is a cyano group or a group represented by general formula (5). In one aspect of the invention, one of R ²¹ to R ²³ is a cyano group. In one aspect of the present invention, one of R ²¹ to R ²³ is a group represented by general formula (5).

In a preferred embodiment of the present invention, L ¹ in general formula (5) is a single bond. In one aspect of the present invention, L ¹ is a divalent linking group, preferably a substituted or unsubstituted arylene group or a substituted or unsubstituted heteroarylene group, more preferably a substituted or unsubstituted arylene group and more preferably a substituted or unsubstituted 1,4-phenylene group (for example, an alkyl group having 1 to 3 carbon atoms as a substituent).
In one aspect of the present invention, R ³¹ and R ³² in general formula (5) are each independently an alkyl group (eg, 1 to 40 carbon atoms), an aryl group (eg, 6 to 30 carbon atoms), a heteroaryl group (eg, 5 to 30 ring skeleton atoms), an alkenyl group (eg, 1 to 40 carbon atoms) and an alkynyl group (eg, 1 to 40 carbon atoms), or a group formed by combining two or more (these groups are hereinafter referred to as "substituent group A groups"). In a preferred embodiment of the present invention, each of R ³¹ and R ³² is independently a substituted or unsubstituted aryl group (eg, having 6 to 30 carbon atoms), and the substituent of the aryl group is a group of substituent group A. can be mentioned. In one preferred aspect of the invention, R ³¹ and R ³² are the same.

In a preferred embodiment of the present invention, ^L2 in general formula (6) is a single bond. In one aspect of the present invention, ^L2 is a divalent linking group, preferably a substituted or unsubstituted arylene group or a substituted or unsubstituted heteroarylene group, more preferably a substituted or unsubstituted arylene group and more preferably a substituted or unsubstituted 1,4-phenylene group (for example, an alkyl group having 1 to 3 carbon atoms as a substituent).
In one aspect of the present invention, R ³³ and R ³⁴ in general formula (6) are each independently a substituted or unsubstituted alkyl group (eg, 1 to 40 carbon atoms), a substituted or unsubstituted alkenyl group (eg, 1 to 40), a substituted or unsubstituted aryl group (eg, 6 to 30 carbon atoms), or a substituted or unsubstituted heteroaryl group (eg, 5 to 30 carbon atoms). Examples of substituents of the alkyl group, alkenyl group, aryl group, and heteroaryl group referred to herein include hydroxyl group, halogen atom (eg, fluorine atom, chlorine atom, bromine atom, iodine atom), alkyl group (eg, C 1-40 ), an alkoxy group (eg, 1 to 40 carbon atoms), an alkylthio group (eg, 1 to 40 carbon atoms), an aryl group (eg, 6 to 30 carbon atoms), an aryloxy group (eg, 6 to 30 carbon atoms), an arylthio group ( (e.g., 6 to 30 carbon atoms), heteroaryl groups (e.g., 5 to 30 ring atoms), heteroaryloxy groups (e.g., 5 to 30 ring atoms), heteroarylthio groups (e.g., ring atoms) 5 to 30), acyl groups (eg, 1 to 40 carbon atoms), alkenyl groups (eg, 1 to 40 carbon atoms), alkynyl groups (eg, 1 to 40 carbon atoms), alkoxycarbonyl groups (eg, 1 to 40 carbon atoms), consisting of an aryloxycarbonyl group (eg, 1 to 40 carbon atoms), a heteroaryloxycarbonyl group (eg, 1 to 40 carbon atoms), a silyl group (eg, a trialkylsilyl group having 1 to 40 carbon atoms), a nitro group and a cyano group; One group selected from the group or a group formed by combining two or more groups can be mentioned (hereinafter, these groups are referred to as "substituent group B groups").
R ³³ and R ³⁴ may be bonded to each other via a single bond or a linking group to form a cyclic structure. In particular, when R ³³ and R ³⁴ are aryl groups, they are preferably bonded to each other via a single bond or a linking group to form a cyclic structure. Examples of the linking group here include -O-, -S-, -N(R ³⁵ )-, -C(R ³⁶ )(R ³⁷ )-, -C(=O)-, and -O -, -S-, -N(R ³⁵ )- and -C(R ³⁶ )(R ³⁷ )- are preferred, and -O-, -S- and -N(R ³⁵ )- are more preferred. R ³⁵ to R ³⁷ each independently represent a hydrogen atom or a substituent. As the substituent, a group of the substituent group A can be selected, or a group of the substituent group B below can be selected, preferably an alkyl group having 1 to 10 carbon atoms and a group having 6 to 14 carbon atoms. It is one group or a combination of two or more groups selected from the group consisting of aryl groups.

The group represented by general formula (6) is preferably a group represented by general formula (7) below.

^L11 in general formula (7) represents a single bond or a divalent linking group. The description and preferred range of L ¹¹ can be referred to the description and preferred range of L ² above.
Each of R ⁴¹ to R ⁴⁸ in general formula (7) independently represents a hydrogen atom or a substituent. R ⁴¹ and R ⁴² , R ⁴² and R ⁴³ , R ⁴³ and R ⁴⁴ , R ⁴⁴ and R ⁴⁵ , R ⁴⁵ and R ⁴⁶ , R ⁴⁶ and R ⁴⁷ , R ⁴⁷ and R ⁴⁸ are bonded together to form a cyclic structure. may be formed. The cyclic structure formed by bonding to each other may be an aromatic ring or an alicyclic ring, or may contain a heteroatom, and the cyclic structure may be a condensed ring of two or more rings. . The heteroatoms referred to here are preferably those selected from the group consisting of nitrogen atoms, oxygen atoms and sulfur atoms. Examples of cyclic structures formed include benzene ring, naphthalene ring, pyridine ring, pyridazine ring, pyrimidine ring, pyrazine ring, pyrrole ring, imidazole ring, pyrazole ring, imidazoline ring, oxazole ring, isoxazole ring, thiazole ring, iso thiazole ring, cyclohexadiene ring, cyclohexene ring, cyclopentaene ring, cycloheptatriene ring, cycloheptadiene ring, cycloheptaene ring, furan ring, thiophene ring, naphthyridine ring, quinoxaline ring, quinoline ring and the like. . For example, a ring formed by condensing a large number of rings such as a phenanthrene ring or a triphenylene ring may be formed. The number of rings contained in the group represented by general formula (7) may be selected from the range of 3-5, or may be selected from the range of 5-7.
Examples of substituents that R ⁴¹ to R ⁴⁸ can take include the groups of the above substituent group B, preferably unsubstituted alkyl groups having 1 to 10 carbon atoms or unsubstituted alkyl groups having 1 to 10 carbon atoms. It is an aryl group having 6 to 10 carbon atoms which may be substituted with an alkyl group. In a preferred embodiment of the present invention, R ⁴¹ to R ⁴⁸ are hydrogen atoms or unsubstituted alkyl groups having 1 to 10 carbon atoms. In a preferred embodiment of the present invention, R ⁴¹ to R ⁴⁸ are hydrogen atoms or unsubstituted aryl groups having 6 to 10 carbon atoms. In a preferred embodiment of the present invention, all of R ⁴¹ to R ⁴⁸ are hydrogen atoms.
In general formula (7), * represents a bonding position.

A preferred embodiment of the present invention uses an azabenzene derivative as the delayed fluorescence material. In a preferred embodiment of the present invention, the azabenzene derivative has an azabenzene structure in which three of the ring skeleton-constituting carbon atoms of the benzene ring are substituted with nitrogen atoms. For example, an azabenzene derivative having a 1,3,5-triazine structure can be preferably selected. In a preferred embodiment of the present invention, the azabenzene derivative has an azabenzene structure in which two of the ring skeleton-constituting carbon atoms of the benzene ring are substituted with nitrogen atoms. For example, azabenzene derivatives having a pyridazine structure, a pyrimidine structure, and a pyrazine structure can be mentioned, and azabenzene derivatives having a pyrimidine structure can be preferably selected. In one aspect of the present invention, the azabenzene derivative has a pyridine structure in which one of the ring skeleton-constituting carbon atoms of the benzene ring is substituted with a nitrogen atom.

In a preferred embodiment of the present invention, a compound represented by the following general formula (8) is used as the delayed fluorescence material.

In general formula (8), at least one of Y ¹ , Y ² and Y ³ represents a nitrogen atom and the rest represent methine groups. In one aspect of the invention, Y ¹ is a nitrogen atom and Y ² and Y ³ are methine groups. Y ¹ and Y ² are preferably nitrogen atoms and Y ³ is preferably a methine group. More preferably, all of Y ¹ to Y ³ are nitrogen atoms.
In general formula (8), Z ¹ to Z ³ each independently represent a hydrogen atom or a substituent, at least one of which is a donor substituent. A donor substituent means a group having a negative Hammett's σp value. Preferably, at least one of Z ¹ to Z ³ is a group containing a diarylamino structure (two aryl groups bonded to the nitrogen atom may be bonded to each other), more preferably the general formula (6 ), for example, a group represented by the general formula (7). In one aspect of the present invention, only one of Z ¹ to Z ³ is a group represented by general formula (6) or (7). In one aspect of the present invention, only two of Z ¹ to Z ³ are each independently a group represented by general formula (6) or (7). In one aspect of the present invention, all of Z ¹ to Z ³ are each independently a group represented by general formula (6) or (7). For details and preferred ranges of general formulas (6) and (7), reference can be made to the corresponding description above. The remaining Z ¹ to Z ³ that are not groups represented by general formulas (6) and (7) are substituted or unsubstituted aryl groups (eg, 6 to 40 carbon atoms, preferably 6 to 20 carbon atoms). The substituents of the aryl group referred to herein include an aryl group (eg, 6 to 20 carbon atoms, preferably 6 to 14 carbon atoms) and an alkyl group (eg, 1 to 20 carbon atoms, preferably 1 to 6). One group selected from the group or a group formed by combining two or more groups can be exemplified. In one aspect of the present invention, general formula (8) does not contain a cyano group.

In a preferred embodiment of the present invention, a compound represented by the following general formula (9) is used as the delayed fluorescence material.

In general formula (9), Ar ¹ forms a cyclic structure that may be substituted with A ¹ and D ¹ below, and represents a benzene ring, naphthalene ring, anthracene ring, or phenanthrene ring. Ar ² and Ar ³ each may form a cyclic structure, and when they form a cyclic structure, they represent a benzene ring, a naphthalene ring, a pyridine ring, or a cyano-substituted benzene ring. m1 represents an integer of 0 to 2; m2 represents an integer of 0 to 1; ^A1 represents a cyano group, a phenyl group, a pyrimidyl group, a triazyl group, or a benzonitrile group. D ¹ represents a substituted or unsubstituted 5H-indolo[3,2,1-de]phenazin-5-yl group or a substituted or unsubstituted heterocyclic condensed carbazolyl group containing no naphthalene structure; ), they may be the ^same or different. Also, the substituents of D ¹ may be bonded to each other to form a cyclic structure.
In one preferred embodiment of the present invention, Ar ¹ is an optionally substituted phenanthrene ring, more preferably a substituted phenanthrene ring. In a preferred embodiment of the present invention, the number of substituents on the phenanthrene ring is one. In a preferred embodiment of the present invention, the number of substituents on the phenanthrene ring is two. In one aspect of the present invention, only one of Ar ² and Ar ³ forms a cyclic structure. In a preferred embodiment of the present invention, both Ar ² and Ar ³ form a cyclic structure.

Preferred compounds that can be used as the delayed fluorescence material are listed below, but the delayed fluorescence material that can be used in the present invention is not limited to these specific examples.

In the present invention, known delayed fluorescence materials other than those described above can be used in appropriate combination with the compound represented by general formula (1). Moreover, even unknown delayed fluorescence materials can be used.
As the delayed fluorescence material, paragraphs 0008 to 0048 and 0095 to 0133 of WO2013/154064, paragraphs 0007 to 0047 and 0073 to 0085 of WO2013/011954, paragraphs 0007 to 0033 and 0059 to 0066 of WO2013/011955, Paragraphs 0008 to 0071 and 0118 to 0133 of WO2013/081088, paragraphs 0009 to 0046 and 0093 to 0134 of JP 2013-256490, paragraphs 0008 to 0020 and 0038 to 0040 of JP 2013-116975, WO2013 / Paragraphs 0007 to 0032 and 0079 to 0084 of 133359, paragraphs 0008 to 0054 and 0101 to 0121 of WO2013/161437, paragraphs 0007 to 0041 and 0060 to 0069 of JP 2014-9352, JP 2014- 9224, paragraphs 0008 to 0048 and 0067 to 0076, JP 2017-119663, paragraphs 0013 to 0025, JP 2017-119664, paragraphs 0013 to 0026, JP 2017-222623, paragraph 0012 to 0025, paragraphs 0010 to 0050 of JP-A-2017-226838, paragraphs 0012-0043 of JP-A-2018-100411, and compounds encompassed by the general formulas described in paragraphs 0016-0044 of WO2018/047853, In particular, exemplary compounds that emit delayed fluorescence can be mentioned. Further, JP 2013-253121, WO2013/133359, WO2014/034535, WO2014/115743, WO2014/122895, WO2014/126200, WO2014/136758, WO2014/13 3121 Publications, WO2014/136860, WO2014/196585, WO2014/189122, WO2014/168101, WO2015/008580, WO2014/203840, WO2015/002213, WO2015/ 016200 publication, WO2015/019725, WO2015/072470, WO2015/108049, WO2015/080182, WO2015/072537, WO2015/080183, JP 2015-129240, WO2015/129 714 publication, WO2015/129715, WO2015/133501, WO2015/136880, WO2015/137244, WO2015/137202, WO2015/137136, WO2015/146541, WO2015/15 9541, WO2019/ 191665, pp. 62-159, and WO2020/111205 [0028]-[0056], which emit delayed fluorescence and which emit delayed fluorescence. The above publications mentioned in this paragraph are hereby incorporated by reference as part of this specification.

The delayed fluorescence material used in the present invention preferably does not contain metal atoms. For example, as the delayed fluorescence material, a compound composed of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms, oxygen atoms and sulfur atoms can be selected. For example, as the delayed fluorescence material, a compound composed of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms and oxygen atoms can be selected. For example, a compound composed of carbon atoms, hydrogen atoms and nitrogen atoms can be selected as the delayed fluorescence material.

(Composition)
The composition of the present invention contains a compound represented by formula (1) and a delayed fluorescence material. In one aspect of the present invention, the composition is composed only of one or more compounds represented by general formula (1) and one or more delayed fluorescence materials. In one aspect of the present invention, the composition comprises only one type of compound represented by general formula (1) and one type of delayed fluorescence material. In one aspect of the present invention, the composition contains a third component in addition to the compound represented by formula (1) and the delayed fluorescence material. The third component here is neither the compound represented by the general formula (1) nor the delayed fluorescence material. Only one type of the third component may be contained, or two or more types may be contained. The content of the third component in the composition may be selected within the range of 30% by weight or less, may be selected within the range of 10% by weight or less, or may be selected within the range of 1% by weight or less. It may be selected, or may be selected within the range of 0.1% by weight or less. In one aspect of the invention, the third component does not emit light. In one aspect of the invention, the third component emits fluorescence. In one preferred aspect of the present invention, the largest component of luminescence from the composition of the present invention is fluorescence (including delayed fluorescence).
In the composition of the present invention, the content of the compound represented by general formula (1) is greater than that of the delayed fluorescence material on a weight basis. The content of the compound represented by the general formula (1) may be selected within a range of 3 times or more by weight the content of the delayed fluorescence material, or may be selected within a range of 10 times or more by weight. However, it may be selected within a range of 100 times by weight or more, may be selected within a range of 1000 times by weight or more, or may be selected within a range of, for example, 10000 times by weight or less.
In the composition of the present invention, it is preferable to select a delayed fluorescence material having an excited singlet energy smaller than the excited singlet energy of the compound represented by formula (1). The difference in excited singlet energy may be 0.1 eV or more, 0.3 eV or more, or 0.5 eV or more, and may be 2 eV or less, 1.5 eV or less, or 1.0 eV or less. You can
The composition of the present invention preferably does not contain metal elements. In one aspect of the invention, the composition of the invention consists exclusively of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms, oxygen atoms, sulfur atoms, boron atoms and halogen atoms. In one aspect of the invention, the composition of the invention consists exclusively of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms and oxygen atoms.

In addition, in one aspect of the present invention, the compound represented by general formula (1) is useful as a host material for use with a delayed fluorescence material and a fluorescent compound. Therefore, in one aspect of the present invention, the composition of the present invention contains a fluorescent compound in addition to the compound represented by formula (1) and the delayed fluorescent material.

The fluorescent compound preferably has a lower lowest excited singlet energy (E _S1 ) than the compound represented by formula (1) and the delayed fluorescent material. The fluorescent compound absorbs energy from the compound represented by general formula (1) in the excited singlet state, the delayed fluorescent material, and the delayed fluorescent material in the excited singlet state through inverse intersystem crossing from the excited triplet state. It receives and transitions to a singlet excited state, and then emits fluorescence when returning to the ground state. The fluorescent compound is not particularly limited as long as it can receive energy from the compound represented by the general formula (1) and the delayed fluorescence material and emit fluorescence. It may be delayed fluorescence. Among them, the luminescent material used as the fluorescent compound preferably emits fluorescence when returning from the lowest excited singlet energy level to the ground energy level. Two or more fluorescent compounds may be used. For example, by using two or more fluorescent compounds with different emission colors, it is possible to emit light of a desired color.
Fluorescent compounds include anthracene derivatives, tetracene derivatives, naphthacene derivatives, pyrene derivatives, perylene derivatives, chrysene derivatives, rubrene derivatives, coumarin derivatives, pyran derivatives, stilbene derivatives, fluorene derivatives, anthryl derivatives, pyrromethene derivatives, terphenyl derivatives, terphenyl derivatives, Phenylene derivatives, fluoranthene derivatives, amine derivatives, quinacridone derivatives, oxadiazole derivatives, malononitrile derivatives, pyran derivatives, carbazole derivatives, julolidine derivatives, thiazole derivatives, derivatives containing metals (Al, Zn), diazaboranaphthoanthracene, etc. A compound having a multiple resonance effect such as a compound having a boron polycyclic aromatic skeleton can be used. These exemplified skeletons may or may not have a substituent. Also, these exemplary skeletons may be combined.

Specific examples of the fluorescent compound include the compounds given as specific examples of the delayed fluorescence material. At this time, the composition of the present invention contains two or more delayed fluorescence materials, and the one with the higher lowest singlet excited energy functions as an assist dopant, and the one with the lower lowest singlet excited energy functions as a fluorescent compound that mainly emits light. The compound used as the fluorescent compound preferably exhibits a PL emission quantum yield of 60% or more, more preferably 80% or more. The compound used as the fluorescent compound preferably exhibits an instantaneous fluorescence lifetime of 50 ns or less, more preferably 20 ns or less. The instantaneous fluorescence lifetime at this time is the luminescence lifetime of the fastest decaying component among multiple exponentially decaying components observed when luminescence lifetime measurement is performed for a compound exhibiting thermally activated delayed fluorescence. The compound used as the third compound preferably has a fluorescence emission rate from the lowest excited singlet (S1) to the ground state higher than an intersystem crossing rate from S1 to the lowest excited triplet (T1). Regarding the calculation method of the rate constant of the compound, the known literature on thermally activated delayed fluorescence materials (H. Uoyama, et al., Nature 492, 234 (2012) and K. Masui, et al., Org. Electron. 14 , 2721, (2013), etc.).

Preferred compounds that can be used as fluorescent compounds that are used together with the delayed fluorescent material are listed below, but the fluorescent compounds that can be used in the present invention are not limited to these specific examples.

In addition, the compounds described in paragraphs 0220 to 0239 of WO2015/022974 can also be particularly preferably employed as the fluorescent compound of the present invention.

In the present invention, it is also preferable to use a compound exhibiting a multiple resonance effect as an assist dopant or a delayed fluorescence material used as a fluorescent compound having a lowest excited singlet energy lower than that of the assist dopant. Compounds exhibiting multiple resonance effects include 5,9-Diphenyl-5H,9H-[1,4]benzazaborino[2,3,4-kl] described in Adv. Mater. 2016, 28, 2777-2781 ]phenazaborine (DABNA-1) is known. In addition, by modifying DABNA-1, energy levels such as the highest transferred molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) can be adjusted to contribute to light emission. is also known (Angew. Chem. Int. Ed. 2018, 57, 11316-11320). Compounds exhibiting such multiple resonance effects can also be widely employed in the present invention.
For example, a compound represented by the following general formula can be used as the compound that exhibits the multiple resonance effect.

In general formula (10), X ¹ and X ² each independently represent O or S;
Y ¹ and Y ² each independently represent a single bond, O, S or C(R ^a )(R ^b ).
R ^1′ to R ^22′ , R ^a and R ^b each independently represent a hydrogen atom, a deuterium atom or a substituent, and at least one of R ^1′ to R ^22′ is a substituent.
R ^1′ and R ^2′ , R ^2′ and R ^3′ , R ^3′ and R ^4′ , R ^5′ and R ^6′ , R ^6′ and R ^7′ , R ^7′ and Y ¹ , Y ¹ and R ^8′ , R ^8′ and R ^9′ , R ^9′ and R ^10′ , R ^10′ and R ^11′ , R ^12′ and R 13′ , R ^13′ and R ¹⁴ ^′ , R ^14′ and R ^{15 '} , R ^16' and R ^17' , R ^17' and R ^18' , R ^18' and Y ² , Y ² and R ^19' , R ^19' and R ^20' , R ^20' and R ^21' , R ^{21 '} and R ^{22 '} may combine with each other to form a cyclic structure. R ^21′ and R ^1′ , R ^4′ and R ^5′ , R ^10′ and R ^12′ , R ^15′ and R ^16′ are not bonded to each other to form a cyclic structure.
CR ^1′ , CR ^2′ , CR ^3′ , CR ^{4′ , CR 5′} , CR ⁶ ^′ , CR ^7′ , C in general formula (10) —R ^8′ , CR ^9′ , CR ^10′ , CR 11′ , CR ^12′ , CR ^13′ ^, CR ^14′ , CR ^15′ , CR ^16′ , CR ^17′ , CR ^18′ , CR ^19′ , CR ^20′ , CR ²¹ ′ and CR ^22′ may be substituted with N;
Specific examples of the compound represented by the general formula (10) are given below, but the compound represented by the general formula (10) that can be used in the present invention should be construed to be limited by the following specific examples. no.

In one embodiment of the present invention, the compound represented by General Formula (1) can be used together with another host material for a light-emitting layer (composition) containing a plurality of host materials. That is, in one aspect of the present invention, the composition of the present invention contains a plurality of host materials containing the compound represented by general formula (1). In the composition of the present invention, a plurality of types of compounds represented by general formula (1) may be used, or a compound represented by general formula (1) and a host material not represented by general formula (1) may be used. They may be used in combination.
Preferred compounds that can be used as the second host material together with the compound represented by the general formula (1) are listed below. It should not be interpreted restrictively.

The form of the composition of the present invention is not particularly limited. In a particularly preferred embodiment of the invention, the composition of the invention is in the form of a film. A film comprising the composition of the present invention may be formed by a wet process or a dry process.
In the wet process, a solution in which the composition of the present invention is dissolved is applied to the surface, and the luminescent layer is formed after removing the solvent. Examples of wet processes include spin coating, slit coating, inkjet (spray), gravure printing, offset printing, and flexographic printing, but are not limited to these. In the wet process, a suitable organic solvent is selected and used that is capable of dissolving the composition of the present invention. In certain embodiments, compounds included in the compositions of the present invention can be introduced with substituents (eg, alkyl groups) that increase their solubility in organic solvents.
A vacuum vapor deposition method can be preferably employed as the dry process. When a vacuum deposition method is employed, each compound constituting the composition of the present invention may be co-deposited from individual deposition sources, or all the compounds may be co-deposited from a single deposition source mixed. . When a single vapor deposition source is used, a mixed powder obtained by mixing powders of all the compounds may be used, a compression molding obtained by compressing the mixed powder may be used, or each compound may be heated and melted and mixed. A mixture that has been cooled after heating may be used. In one embodiment, the composition ratio of the plurality of compounds contained in the vapor deposition source is reduced by co-deposition under conditions in which the vapor deposition rates (weight reduction rates) of the plurality of compounds contained in the single vapor deposition source match or substantially match. It is possible to form a film having a composition ratio corresponding to A film having a desired composition ratio can be easily formed by mixing a plurality of compounds at the same composition ratio as that of the film to be formed, and using this as an evaporation source. In one embodiment, the temperature at which each of the co-deposited compounds has the same weight loss rate can be identified and used as the temperature during co-deposition. When the film is formed by a vapor deposition method, the molecular weight of each compound constituting the composition is preferably 1500 or less, more preferably 1200 or less, further preferably 1000 or less, and 900 or less. It is even more preferred to have The lower limit of the molecular weight may be 450, 500, or 600, for example.

(Organic light-emitting element)
Excellent organic light-emitting devices such as organic photoluminescence devices (organic PL devices) and organic electroluminescence devices (organic EL devices) can be provided by forming a light-emitting layer comprising the composition of the present invention. The organic light-emitting device of the present invention is a fluorescent light-emitting device, and the largest component of light emitted from the device is fluorescence (the fluorescence referred to herein includes delayed fluorescence).
The thickness of the light-emitting layer can be, for example, 1-15 nm, 2-10 nm, or 3-7 nm.
An organic photoluminescence device has a structure in which at least a light-emitting layer is formed on a substrate. Also, the organic electroluminescence element has a structure in which at least an anode, a cathode, and an organic layer are formed between the anode and the cathode. The organic layer includes at least a light-emitting layer, and may consist of only the light-emitting layer, or may have one or more organic layers in addition to the light-emitting layer. Such other organic layers can include hole transport layers, hole injection layers, electron blocking layers, hole blocking layers, electron injection layers, electron transport layers, exciton blocking layers, and the like. The hole transport layer may be a hole injection transport layer having a hole injection function, and the electron transport layer may be an electron injection transport layer having an electron injection function.
When the organic light-emitting device of the present invention is a multi-wavelength light-emitting organic light-emitting device, the emission with the shortest wavelength may include delayed fluorescence. In addition, it is also possible that the emission with the shortest wavelength does not contain delayed fluorescence.
An organic light-emitting device using the composition of the present invention, when excited by thermal or electronic means, has a blue, green, yellow, orange, and red region (for example, 420-500 nm, 500 nm) in the ultraviolet region and the visible spectrum. ~600 nm or 600-700 nm) or in the near infrared region. For example, organic light emitting devices can emit light in the red or orange region (eg, 620-780 nm). For example, organic light emitting devices can emit light in the orange or yellow region (eg, 570-620 nm). For example, an organic light emitting device can emit light in the green region (eg, 490-575 nm). For example, an organic light emitting device can emit light in the blue region (eg, 400-490 nm). For example, organic light emitting devices can emit light in the ultraviolet spectral region (eg, 280-400 nm). For example, organic light emitting devices can emit light in the infrared spectral region (eg, 780 nm to 2 μm).
It is preferable that the largest component of light emitted from the organic light-emitting device using the composition of the present invention is light emitted from the delayed fluorescence material contained in the composition of the present invention. Emission from the compound represented by the general formula (1) is preferably less than 10% of the light emission from the organic light-emitting device, for example, less than 1%, less than 0.1%, less than 0.01%, detection limit It may be below. Emission from the delayed fluorescence material may be, for example, greater than 50%, greater than 90%, greater than 99% of the emission from the organic light emitting device. When the layer containing the composition of the present invention (light-emitting layer) contains a fluorescent material as the third component, the maximum component of light emitted from the organic light-emitting device may be light emitted from the fluorescent material. In that case, the emission from the luminescent material may be, for example, greater than 50%, greater than 90%, greater than 99% of the emission from the organic light emitting device.

Each member of the organic electroluminescence element and each layer other than the light-emitting layer will be described below.

Base material:
In some embodiments, the organic electroluminescent device of the present invention is held by a substrate, which is not particularly limited and commonly used in organic electroluminescent devices such as glass, transparent plastic, quartz and silicon. Any material formed by

anode:
In some embodiments, the anode of the organic electroluminescent device is made from metals, alloys, conductive compounds, or combinations thereof. In some embodiments, the metal, alloy or conductive compound has a high work function (4 eV or greater). In some embodiments, the metal is Au. In some embodiments, the conductive transparent material is selected from CuI, indium tin oxide (ITO), _SnO2 and ZnO. Some embodiments use amorphous materials that can form transparent conductive films, such as IDIXO (In ₂ O ₃ —ZnO). In some embodiments, the anode is a thin film. In some embodiments, the thin film is made by evaporation or sputtering. In some embodiments, the film is patterned by photolithographic methods. In some embodiments, if the pattern does not need to be highly precise (eg, about 100 μm or greater), the pattern may be formed using a mask with a shape suitable for vapor deposition or sputtering onto the electrode material. In some embodiments, wet film forming methods such as printing and coating methods are used when coating materials such as organic conductive compounds can be applied. In some embodiments, the anode has a transmittance of greater than 10% when emitted light passes through the anode, and the anode has a sheet resistance of several hundred ohms per unit area or less. In some embodiments, the thickness of the anode is 10-1,000 nm. In some embodiments, the thickness of the anode is 10-200 nm. In some embodiments, the thickness of the anode varies depending on the material used.

cathode:
In some embodiments, the cathode is made of electrode materials such as metals with a low work function (4 eV or less) (referred to as electron-injecting metals), alloys, conductive compounds, or combinations thereof. In some embodiments, the electrode material is sodium, sodium-potassium alloys, magnesium, lithium, magnesium-copper mixtures, magnesium-silver mixtures, magnesium-aluminum mixtures, magnesium-indium mixtures, aluminum-aluminum oxide ( _Al2 O ₃ ) mixtures, indium, lithium-aluminum mixtures and rare earth elements. In some embodiments, a mixture of an electron-injecting metal and a second metal that is a stable metal with a higher work function than the electron-injecting metal is used. In some embodiments, the mixture is selected from magnesium-silver mixtures, magnesium-aluminum mixtures, magnesium-indium mixtures, aluminum-aluminum oxide (Al ₂ O ₃ ) mixtures, lithium-aluminum mixtures and aluminum. In some embodiments, the mixture improves electron injection properties and resistance to oxidation. In some embodiments, the cathode is manufactured by depositing or sputtering the electrode material as a thin film. In some embodiments, the cathode has a sheet resistance of no more than several hundred ohms per unit area. In some embodiments, the thickness of said cathode is between 10 nm and 5 μm. In some embodiments, the thickness of the cathode is 50-200 nm. In some embodiments, either one of the anode and cathode of the organic electroluminescent device is transparent or translucent to allow transmission of emitted light. In some embodiments, transparent or translucent electroluminescent elements enhance light radiance.
In some embodiments, the cathode is formed of a conductive transparent material as described above for the anode, thereby forming a transparent or translucent cathode. In some embodiments, the device includes an anode and a cathode, both transparent or translucent.

Injection layer:
The injection layer is the layer between the electrode and the organic layer. In some embodiments, the injection layer reduces drive voltage and enhances light radiance. In some embodiments, the injection layer comprises a hole injection layer and an electron injection layer. The injection layer can be placed between the anode and the light-emitting layer or hole-transporting layer and between the cathode and the light-emitting layer or electron-transporting layer. In some embodiments, an injection layer is present. In some embodiments, there is no injection layer.
Preferred examples of compounds that can be used as the hole injection material are given below.

Next, preferred examples of compounds that can be used as the electron injection material are given.

Barrier layer:
A barrier layer is a layer that can prevent charges (electrons or holes) and/or excitons present in the light-emitting layer from diffusing out of the light-emitting layer. In some embodiments, an electron blocking layer is between the light-emitting layer and the hole-transporting layer to block electrons from passing through the light-emitting layer to the hole-transporting layer. In some embodiments, a hole blocking layer is between the emissive layer and the electron transport layer and blocks holes from passing through the emissive layer to the electron transport layer. In some embodiments, the barrier layer prevents excitons from diffusing out of the emissive layer. In some embodiments, the electron blocking layer and the hole blocking layer constitute an exciton blocking layer. As used herein, the terms "electron blocking layer" or "exciton blocking layer" include layers that have the functionality of both an electron blocking layer and an exciton blocking layer.

Hole blocking layer:
A hole blocking layer functions as an electron transport layer. In some embodiments, the hole blocking layer blocks holes from reaching the electron transport layer during electron transport. In some embodiments, the hole blocking layer increases the probability of recombination of electrons and holes in the emissive layer. The materials used for the hole blocking layer can be the same materials as described above for the electron transport layer.
Preferred examples of compounds that can be used in the hole blocking layer are given below.

Electron barrier layer:
The electron blocking layer transports holes. In some embodiments, the electron blocking layer prevents electrons from reaching the hole transport layer during hole transport. In some embodiments, the electron blocking layer increases the probability of recombination of electrons and holes in the emissive layer. The materials used for the electron blocking layer may be the same materials as described above for the hole transport layer.
Specific examples of preferred compounds that can be used as the electron barrier material are given below.

Exciton barrier layer:
The exciton blocking layer prevents excitons generated through recombination of holes and electrons in the light emitting layer from diffusing to the charge transport layer. In some embodiments, the exciton blocking layer allows effective confinement of excitons in the emissive layer. In some embodiments, the light emission efficiency of the device is improved. In some embodiments, an exciton blocking layer is adjacent to the emissive layer on either the anode side or the cathode side, and on both sides thereof. In some embodiments, when an exciton blocking layer is present on the anode side, it may be present between and adjacent to the hole-transporting layer and the light-emitting layer. In some embodiments, when an exciton blocking layer is present on the cathode side, it may be between and adjacent to the emissive layer and the cathode. In some embodiments, a hole-injection layer, electron-blocking layer, or similar layer is present between the anode and an exciton-blocking layer adjacent to the light-emitting layer on the anode side. In some embodiments, a hole injection layer, electron blocking layer, hole blocking layer, or similar layer is present between the cathode and an exciton blocking layer adjacent to the emissive layer on the cathode side. In some embodiments, the exciton blocking layer comprises an excited singlet energy and an excited triplet energy, at least one of which is higher than the excited singlet energy and triplet energy, respectively, of the emissive material.

Hole transport layer:
The hole-transporting layer comprises a hole-transporting material. In some embodiments, the hole transport layer is a single layer. In some embodiments, the hole transport layer has multiple layers.
In some embodiments, the hole transport material has one property of a hole injection or transport property and an electron barrier property. In some embodiments, the hole transport material is an organic material. In some embodiments, the hole transport material is an inorganic material. Examples of known hole transport materials that can be used in the present invention include, but are not limited to, triazole derivatives, oxadiazole derivatives, imidazole derivatives, carbazole derivatives, indolocarbazole derivatives, polyarylalkane derivatives, pyrazoline derivatives, pyrazolones. derivatives, phenylenediamine derivatives, allylamine derivatives, amino-substituted chalcone derivatives, oxazole derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives, aniline copolymers and conductive polymer oligomers (especially thiophene oligomers), or combinations thereof. are mentioned. In some embodiments, the hole transport material is selected from porphyrin compounds, aromatic tertiary amine compounds and styrylamine compounds. In some embodiments, the hole transport material is an aromatic tertiary amine compound. Specific examples of preferred compounds that can be used as the hole-transporting material are given below.

Electron transport layer:
The electron transport layer includes an electron transport material. In some embodiments, the electron transport layer is a single layer. In some embodiments, the electron transport layer has multiple layers.
In some embodiments, the electron-transporting material need only function to transport electrons injected from the cathode to the emissive layer. In some embodiments, the electron transport material also functions as a hole blocking material. Examples of electron-transporting layers that can be used in the present invention include, but are not limited to, nitro-substituted fluorene derivatives, diphenylquinone derivatives, thiopyran dioxide derivatives, carbodiimides, fluorenylidene methane derivatives, anthraquinodimethanes, anthrone derivatives, oxazide Azole derivatives, azole derivatives, azine derivatives or combinations thereof, or polymers thereof. In some embodiments, the electron transport material is a thiadiazole derivative or a quinoxaline derivative. In some embodiments, the electron transport material is a polymeric material. Specific examples of preferred compounds that can be used as the electron-transporting material are given below.

Furthermore, examples of preferred compounds as materials that can be added to each organic layer are given. For example, it may be added as a stabilizing material.

Preferred materials that can be used in organic electroluminescence elements are specifically exemplified, but materials that can be used in the present invention are not limitedly interpreted by the following exemplified compounds. Moreover, even compounds exemplified as materials having specific functions can be used as materials having other functions.

device:
In some embodiments, the emissive layer is incorporated into the device. For example, devices include, but are not limited to, OLED bulbs, OLED lamps, television displays, computer monitors, mobile phones and tablets.
In some embodiments, an electronic device includes an OLED having at least one organic layer including an anode, a cathode, and a light-emitting layer between the anode and the cathode.
In some embodiments, compositions described herein can be incorporated into various photosensitive or photoactivated devices, such as OLEDs or optoelectronic devices. In some embodiments, the composition may be useful in facilitating charge or energy transfer within a device and/or as a hole transport material. Examples of such devices include organic light emitting diodes (OLEDs), organic integrated circuits (OICs), organic field effect transistors (O-FETs), organic thin film transistors (O-TFTs), organic light emitting transistors (O-LETs), and organic solar cells. (O-SC), organic optical detectors, organic photoreceptors, organic field-quench devices (O-FQD), luminescent fuel cells (LEC) or organic laser diodes (O-lasers).

Bulb or Lamp:
In some embodiments, an electronic device includes an OLED including at least one organic layer including an anode, a cathode, and a light-emitting layer between the anode and the cathode.
In some embodiments, the device includes OLEDs of different colors. In some embodiments, the device includes an array including combinations of OLEDs. In some embodiments, said combination of OLEDs is a combination of three colors (eg RGB). In some embodiments, the combination of OLEDs is a combination of colors other than red, green, and blue (eg, orange and yellow-green). In some embodiments, said combination of OLEDs is a combination of two, four or more colors.
In some embodiments, the device
a circuit board having a first side with a mounting surface and a second opposite side and defining at least one opening;
at least one OLED on the mounting surface, wherein the at least one OLED comprises at least one organic layer comprising an anode, a cathode, and a light-emitting layer between the anode and the cathode to emit light; at least one OLED comprising
a housing for the circuit board;
at least one connector disposed at an end of said housing, said housing and said connector defining a package suitable for attachment to a lighting fixture.
In some embodiments, the OLED light comprises multiple OLEDs mounted on a circuit board such that light is emitted in multiple directions. In some embodiments, some light emitted in the first direction is polarized and emitted in the second direction. In some embodiments, a reflector is used to polarize light emitted in the first direction.

Display or screen:
In some embodiments, the emissive layers of the invention can be used in screens or displays. In some embodiments, the compounds of the present invention are deposited onto a substrate using processes such as, but not limited to, vacuum evaporation, deposition, evaporation or chemical vapor deposition (CVD). In some embodiments, the substrate is a photoplate structure useful in two-sided etching to provide unique aspect ratio pixels. Said screens (also called masks) are used in the manufacturing process of OLED displays. The corresponding artwork pattern design allows placement of very steep narrow tie-bars between pixels in the vertical direction as well as large and wide beveled openings in the horizontal direction. This allows for the fine patterning of pixels required for high resolution displays while optimizing chemical vapor deposition on the TFT backplane.
The internal patterning of the pixels makes it possible to construct three-dimensional pixel openings with various aspect ratios in the horizontal and vertical directions. Additionally, the use of imaged "stripes" or halftone circles in pixel areas protects etching in specific areas until these specific patterns are undercut and removed from the substrate. All pixel areas are then treated with a similar etch rate, but their depth varies with the halftone pattern. Varying the size and spacing of the halftone patterns allows etching with varying degrees of protection within the pixel, allowing for the localized deep etching necessary to form steep vertical bevels. .
A preferred material for the evaporation mask is Invar. Invar is a metal alloy that is cold rolled into long thin sheets in steel mills. Invar cannot be electrodeposited onto a spin mandrel as a nickel mask. A suitable and low-cost method for forming the open areas in the deposition mask is by wet chemical etching.
In some embodiments, the screen or display pattern is a matrix of pixels on a substrate. In some embodiments, screen or display patterns are fabricated using lithography (eg, photolithography and e-beam lithography). In some embodiments, the screen or display pattern is processed using wet chemical etching. In a further embodiment the screen or display pattern is fabricated using plasma etching.

Device manufacturing method:
An OLED display is generally manufactured by forming a large mother panel and then cutting the mother panel into cell panels. Generally, each cell panel on a mother panel is formed by forming a thin film transistor (TFT) having an active layer and source/drain electrodes on a base substrate, coating the TFT with a planarizing film, pixel electrodes, and a light emitting layer. , a counter electrode and an encapsulation layer, are sequentially formed and cut from the mother panel.
An OLED display is generally manufactured by forming a large mother panel and then cutting the mother panel into cell panels. Generally, each cell panel on a mother panel is formed by forming a thin film transistor (TFT) having an active layer and source/drain electrodes on a base substrate, coating the TFT with a planarizing film, pixel electrodes, and a light emitting layer. , a counter electrode and an encapsulation layer, are sequentially formed and cut from the mother panel.

In another aspect of the invention, there is provided a method of manufacturing an organic light emitting diode (OLED) display, the method comprising:
forming a barrier layer on the base substrate of the mother panel;
forming a plurality of display units on the barrier layer in cell panel units;
forming an encapsulation layer over each of the display units of the cell panel;
and applying an organic film to the interfaces between the cell panels.
In some embodiments, the barrier layer is an inorganic film, eg, made of SiNx, and the edges of the barrier layer are covered with an organic film, made of polyimide or acrylic. In some embodiments, the organic film helps the mother panel to be softly cut into cell panels.
In some embodiments, a thin film transistor (TFT) layer has an emissive layer, a gate electrode, and source/drain electrodes. Each of the plurality of display units may have a thin film transistor (TFT) layer, a planarization film formed on the TFT layer, and a light-emitting unit formed on the planarization film; The applied organic film is made of the same material as the material of the planarizing film and is formed at the same time as the planarizing film is formed. In some embodiments, the light-emitting unit is coupled to the TFT layer by a passivation layer, a planarizing film therebetween, and an encapsulation layer that covers and protects the light-emitting unit. In some embodiments of the manufacturing method, the organic film is not connected to the display unit or encapsulation layer.

Each of the organic film and the planarizing film may include one of polyimide and acrylic. In some embodiments, the barrier layer may be an inorganic film. In some embodiments, the base substrate may be formed of polyimide. The method further includes attaching a carrier substrate made of a glass material to one surface of a base substrate made of polyimide before forming a barrier layer on another surface of the base substrate; separating the carrier substrate from the base substrate prior to cutting along the interface. In some embodiments, the OLED display is a flexible display.
In some embodiments, the passivation layer is an organic film placed on the TFT layer to cover the TFT layer. In some embodiments, the planarizing film is an organic film formed over a passivation layer. In some embodiments, the planarizing film is formed of polyimide or acrylic, as is the organic film formed on the edge of the barrier layer. In some embodiments, the planarizing film and the organic film are formed simultaneously during the manufacture of an OLED display. In some embodiments, the organic film may be formed on the edge of the barrier layer such that a portion of the organic film is in direct contact with the base substrate and a remaining portion of the organic film is , in contact with the barrier layer while surrounding the edges of the barrier layer.

In some embodiments, the emissive layer comprises a pixel electrode, a counter electrode, and an organic emissive layer disposed between the pixel electrode and the counter electrode. In some embodiments, the pixel electrodes are connected to source/drain electrodes of the TFT layer.
In some embodiments, when a voltage is applied to the pixel electrode through the TFT layer, a suitable voltage is formed between the pixel electrode and the counter electrode, causing the organic light-emitting layer to emit light, thereby displaying an image. is formed. An image forming unit having a TFT layer and a light emitting unit is hereinafter referred to as a display unit.
In some embodiments, the encapsulation layer that covers the display unit and prevents the penetration of external moisture may be formed into a thin encapsulation structure in which organic films and inorganic films are alternately laminated. In some embodiments, the encapsulation layer has a thin film-like encapsulation structure in which multiple thin films are stacked. In some embodiments, the organic film applied to the interface portion is spaced apart from each of the plurality of display units. In some embodiments, the organic film is formed such that a portion of the organic film is in direct contact with the base substrate and a remaining portion of the organic film is in contact with the barrier layer while surrounding the edges of the barrier layer. be done.

In one embodiment, the OLED display is flexible and uses a flexible base substrate made of polyimide. In some embodiments, the base substrate is formed on a carrier substrate made of glass material, and then the carrier substrate is separated.
In some embodiments, a barrier layer is formed on the surface of the base substrate opposite the carrier substrate. In one embodiment, the barrier layer is patterned according to the size of each cell panel. For example, a base substrate is formed on all surfaces of a mother panel, while barrier layers are formed according to the size of each cell panel, thereby forming grooves at the interfaces between the barrier layers of the cell panels. Each cell panel can be cut along the groove.

In some embodiments, the manufacturing method further comprises cutting along the interface, wherein a groove is formed in the barrier layer, at least a portion of the organic film is formed with the groove, and the groove is Does not penetrate the base substrate. In some embodiments, a TFT layer of each cell panel is formed, and a passivation layer, which is an inorganic film, and a planarization film, which is an organic film, are placed on and cover the TFT layer. At the same time that the planarizing film, eg made of polyimide or acrylic, is formed, the interface grooves are covered with an organic film, eg made of polyimide or acrylic. This prevents cracking by having the organic film absorb the impact that occurs when each cell panel is cut along the groove at the interface. That is, if all the barrier layers are completely exposed without an organic film, when each cell panel is cut along the groove at the interface, the resulting impact will be transferred to the barrier layers, thereby creating a risk of cracking. increases. However, in one embodiment, the grooves at the interfaces between the barrier layers are coated with an organic film to absorb shocks that might otherwise be transmitted to the barrier layers, so that each cell panel is softly cut and the barrier layers It may prevent cracks from forming. In one embodiment, the organic film covering the groove of the interface and the planarizing film are spaced apart from each other. For example, when the organic film and the planarizing film are connected to each other as a single layer, external moisture may enter the display unit through the planarizing film and the portion where the organic film remains. The organic film and planarizing film are spaced from each other such that the organic film is spaced from the display unit.

In some embodiments, the display unit is formed by forming a light emitting unit and an encapsulating layer is placed over the display unit to cover the display unit. Thereby, after the mother panel is completely manufactured, the carrier substrate carrying the base substrate is separated from the base substrate. In some embodiments, when the laser beam is directed at the carrier substrate, the carrier substrate separates from the base substrate due to the difference in coefficient of thermal expansion between the carrier substrate and the base substrate.
In some embodiments, the mother panel is cut into cell panels. In some embodiments, the mother panel is cut along the interfaces between the cell panels using a cutter. In some embodiments, the interface groove along which the mother panel is cut is coated with an organic film so that the organic film absorbs impact during cutting. In some embodiments, the barrier layer can be prevented from cracking during cutting.
In some embodiments, the method reduces the reject rate of the product and stabilizes its quality.
Another embodiment includes a barrier layer formed on a base substrate, a display unit formed on the barrier layer, an encapsulation layer formed on the display unit, and an organic layer applied to the edges of the barrier layer. An OLED display comprising a film.

The features of the present invention will be more specifically described below with reference to Synthesis Examples and Examples. The materials, processing details, processing procedures, etc. described below can be changed as appropriate without departing from the gist of the present invention. Therefore, the scope of the present invention should not be construed to be limited by the specific examples shown below. In addition, the evaluation of the light emission characteristics was performed using a source meter (manufactured by Keithley: 2400 series), a semiconductor parameter analyzer (manufactured by Agilent Technologies: E5273A), an optical power meter measuring device (manufactured by Newport: 1930C), and an optical spectroscope. (Ocean Optics: USB2000), a spectroradiometer (Topcon: SR-3) and a streak camera (Hamamatsu Photonics, Model C4334).
In the following Synthesis Examples, compounds included in the general formula (1) were synthesized.

(Synthesis Example 1) Synthesis of Compound 1

2-bromo-8-phenyldibenzofuran (2.53 g, 7.83 mmol), 4-(9H-carbazol-9-yl)phenylboronic acid (2.7 g, 9.4 mmol), tetrakistriphenylphosphine palladium (0 ) (0.9 g, 0.78 mmol) and potassium carbonate (23.5 g, 3.25 mmol) were dissolved in a mixed solution of tetrahydrofuran and water (50/25 ml) and stirred at 75° C. for 18 hours. The reaction solution was cooled to room temperature, the solvent was removed, the obtained solid was washed with water, chloroform was added, the solid was dried over magnesium sulfate, and the solvent was removed. The resulting solid was purified by silica gel column chromatography (developing solvent: hexane:chloroform=7:3). Further recrystallization (toluene/methanol) gave Compound 1 as a white solid (3.13 g, 82%).
¹ H NMR (400MHz, CDCl ₃ , δ): 8.3 (s, 1H), 8.23 (s, 1H), 8.18 (s, 1H), 8.16 (s, 1H), 7.92 (d, J = 8 Hz, 2H ), 7.81 (d, J = 8 Hz, 1H), 7.75-7.66 (m, 7H), 7.53-7.36 (m, 7H), 7.31 (t, J = 7 Hz, 2H).
MS ₍ ASAP): 486.29 (M+H ⁺ ). Calcd. for _C36H23NO : 485.18.

(Synthesis Example 2) Synthesis of Compound 16

2-phenyl-8-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-dibenzofuran (2.69 g, 6.75 mmol), 9-(4-bromophenyl) -3-phenyl-9H-carbazole (2.74 g, 8.1 mmol), tetrakistriphenylphosphine palladium (0) (0.79 g, 0.68 mmol), potassium carbonate (2.8 g, 20.3 mmol) in tetrahydrofuran and water (50/25 ml), and stirred at 75° C. for 16 hours. The reaction solution was cooled to room temperature, the solvent was removed, the obtained solid was washed with water, chloroform was added, the solid was dried over magnesium sulfate, and the solvent was removed. The resulting solid was purified by silica gel column chromatography (developing solvent: hexane:chloroform=7:3). Further recrystallization (toluene/acetonitrile) gave compound 16 as a white solid (2 g, 53%).
¹ H NMR (400 MHz, CDCl ₃ , δ): 8.38 (s, 1H), 8.31 (s, 1H), 8.24 (s, 1H), 8.22 (d, J = 8 Hz, 1H), 7.94 (d, J = 8 Hz, 2H), 7.82 (d, J = 8 Hz, 1H), 7.76-7.67 (m, 10H), 7.58-7.45 (m, 7H), 7.43-7.32 (m, 3H).
MS ₍ ASAP): 562.32 (M+H ⁺ ). Calcd. for _C42H27 NO: 561.21.

(Synthesis Example 3) Synthesis of compound 512

A white solid compound a was obtained in the same manner as in Synthesis Example 2, except that 9-(4-bromophenyl)-3-phenyl-9H-carbazole was changed to 1-bromo-4-iodobenzene (2 .26 g, 77%).
¹ H NMR (400MHz, CDCl ₃ , δ): 8.19 (dd, J = 2.0 Hz, 0.8 Hz, 1H), 8.16 (dd, J = 1.6 Hz, 0.8 Hz, 1H), 7.72 (dd, J = 8.4 Hz , 2.0 Hz, 1H), 7.70-7.67 (m, 2H), 7.66-7.63 (m, 3H), 7.62-7.59 (m, 2H), 7.57-7.53 (m, 2H), 7.52-7.47 (m, 2H ), 7.41-7.36 (m, 1H).
MS (ASAP): 399.12 (M+H ⁺ ). _Calcd . for _C24H15BrO : 398.03.

Compound a (1.37 g, 3.44 mmol), carbazole-1,2,3,4,5,6,7,8-d8 (0.66 g, 3.78 mmol), tris(dibenzylideneacetone) dipalladium ( 0) (0.31 g, 0.344 mmol), tri-tert-butylphosphonium tetrafluoroborate (0.20 g, 0.688 mmol) and sodium tert-butoxide (0.66 g, 6.88 mmol) in toluene (35 mL) and refluxed for 15 hours. The reaction liquid was cooled to room temperature, the solvent was removed after filtering an insoluble matter. Chloroform was added to the residue and washed twice with water. The chloroform solution was dried with magnesium sulfate, filtered, and then the solvent was removed. The resulting solid was purified by silica gel column chromatography (developing solvent: hexane:chloroform=8:2). Further recrystallization (toluene/methanol) gave compound 512 as a white solid (1.25 g, 74%).
¹ H NMR (400MHz, CDCl ₃ , δ): 8.31 (d, J = 2.0 Hz, 1H), 8.24 (d, J = 1.6 Hz, 1H), 7.92 (d, J = 8.4 Hz, 2H), 7.82 ( dd, J = 8.8 Hz, 2.0 Hz, 1H), 7.76-7.67 (m, 7H), 7.53-7.48 (m, 2H), 7.42-7.37 (m, 1H).
MS ( _ASAP ): _494.37 (M+H ⁺ ). Calcd. for _C36H15D8 NO: 493.23.

(Example 1) Preparation of green organic electroluminescence device with a different host material On a glass substrate having an anode made of indium tin oxide (ITO) having a thickness of 50 nm, each thin film was formed by vacuum deposition. , and laminated at a degree of vacuum of 5×10 ⁻⁵ Pa. First, HAT-CN was formed to a thickness of 10 nm on ITO, and NPD was formed thereon to a thickness of 30 nm. Then, TrisPCz was formed thereon to a thickness of 10 nm. Compound 1 and TADF1 were then co-deposited from different deposition sources to form a 40 nm thick light-emitting layer. The contents of compound 1 and TADF1 were 55% by mass and 45% by mass. SF3TRZ was formed thereon to a thickness of 10 nm, and SF3TRZ and Liq were co-deposited thereon from different vapor deposition sources at 70% by mass and 30% by mass, respectively, to form a 30 nm thick film. Furthermore, Liq was formed to a thickness of 2 nm, and then aluminum (Al) was deposited to a thickness of 100 nm to form a cathode. The organic electroluminescence element 1 was produced by the above procedure.
A comparative element 1-1 was produced according to the same procedure except that the comparative compound 1 was used instead of the compound 1.
When electricity was applied to the electrodes of each of the fabricated devices, green delayed fluorescence was observed. Further, when the driving voltage was measured at 6.3 mA/cm ² , the device 1 of the present invention was 0.3 V lower than the comparative device 1-1. Further, when the time (LT95) required for the light emission intensity to reach 95% of that at the start of driving when driven at 25.2 mA/cm ² was measured, the element 1 of the present invention was higher than the comparative element 1-1. 1.35 times longer. From this, it was confirmed that when the compound of the present invention is used in combination with the delayed fluorescence material, the driving voltage becomes lower and the device life becomes longer.

(Example 2) Preparation of blue organic electroluminescent device with different host materials The light-emitting layer of Example 1 was co-deposited with 70% by mass and 30% by mass of compound 1 and TADF85 from different deposition sources to a thickness of 40 nm. A device 2-1 was fabricated according to the same procedure as in Example 1, except for the fact that it was formed in .
Elements 2-2 and 2-3 were prepared according to the same procedure except that Compound 16 or Compound 512 was used instead of Compound 1.
A comparative element 2-1 was produced according to the same procedure except that the comparative compound 2 was used instead of the compound 1.
When electricity was applied to the electrodes of each of the fabricated devices, blue delayed fluorescence was observed. For each element, the driving voltage was measured at a current density of 2.0 mA/cm ² , and the difference (relative value) from the driving voltage of the comparative element 2-1 was obtained. Table 3 shows the results. The results in Table 3 show that the driving voltage is also lowered when the compound of the present invention is used together with the blue delayed fluorescent material.

(Example 3) Preparation of red organic electroluminescence device with different host materials The light-emitting layer of Example 1 was prepared by using compound 1, TADF72, and F1 from different vapor deposition sources at 59.5% by mass, 40% by mass, and 0.5% by mass. %, and formed to a thickness of 40 nm.
A comparative element 3-1 was produced according to the same procedure except that the comparative compound 1 was used instead of the compound 1.
When electricity was applied to the electrodes of each of the fabricated devices, red delayed fluorescence was observed. Further, when the driving voltage was measured at 6.3 mA/cm ² , the element 3 of the present invention was 0.3 V lower than the comparative element 3-1. Further, when the external quantum yield (EQE) was measured at 6.3 mA/cm ² , the device 3 of the present invention was 10% higher than the comparative device 3-1. From this, it was confirmed that even when the compound of the present invention is used together with a delayed fluorescence material or a fluorescent material, the driving voltage is lowered and the luminous efficiency is improved.

(Example 4) Fabrication of another red organic electroluminescence device by changing the host material The light-emitting layer of Example 1 was prepared by adding 64.7% by mass, 35% by mass, 0.7% by mass of compound 1, TADF86 and E35 from different vapor deposition sources. A device 4-1 was fabricated according to the same procedure as in Example 1 except that it was co-deposited at 3% by mass to form a film having a thickness of 40 nm.
Device 4-2 was fabricated according to the same procedure except that compound 512 was used instead of compound 1.
A comparative element 4-1 was produced according to the same procedure except that the comparative compound 3 was used instead of the compound 1.
When electricity was applied to the electrodes of each of the fabricated devices, red delayed fluorescence was observed. When driving at 50.0 mA/cm ² , the time (LT95) required for the light emission intensity to reach 95% of that at the start of driving was measured, and the ratio (relative value) of the comparative element 4-1 to the time was obtained. Table 4 shows. The results in Table 4 show that the device life is prolonged even when the compound of the present invention is used together with the delayed fluorescent material and the fluorescent material.

(Example 5) Preparation of green organic electroluminescence device with different electron barrier materials Each thin film was formed by vacuum deposition on a glass substrate on which an anode made of indium tin oxide (ITO) with a thickness of 50 nm was formed. and laminated at a degree of vacuum of 5×10 ⁻⁵ Pa. First, HAT-CN was formed on ITO to a thickness of 10 nm, NPD was formed thereon to a thickness of 30 nm, and TrisPCz was formed to a thickness of 10 nm. Next, Compound 1 was formed thereon as an electron blocking layer to a thickness of 10 nm. Next, H1 and TADF1 were co-deposited from different deposition sources to form a 40 nm thick emitting layer. The contents of H1 and TADF1 were 55% by mass and 45% by mass. SF3TRZ was formed thereon to a thickness of 10 nm, and SF3TRZ and Liq were co-deposited thereon from different vapor deposition sources at 70% by mass and 30% by mass, respectively, to form a 30 nm thick film. Furthermore, Liq was formed to a thickness of 2 nm, and then aluminum (Al) was deposited to a thickness of 100 nm to form a cathode. The organic electroluminescence element 5 was produced by the above procedure.
A comparative element 5-1 was produced according to the same procedure except that the comparative compound 1 was used instead of the compound 1.
When electricity was applied to the electrodes of each of the fabricated devices, green delayed fluorescence was observed. Further, when the time (LT95) required for the light emission intensity to reach 95% of that at the start of driving when driven at 25.2 mA/cm ² was measured, the element 5 of the present invention was higher than the comparative element 5-1. 1.5 times longer. From this, it was confirmed that the use of the compound of the present invention as an electron barrier material prolongs the life of the device.

(Example 6) Production of a red organic electroluminescent device using two types of hosts, a host material and a second host material When forming a light-emitting layer, compound 1, H2, TADF15, and E35 were co-deposited from different deposition sources. An organic electroluminescence device 6-1 was produced in the same manner as in Example 1, except that the film was formed to a thickness of 40 nm. At this time, the amount ratio of compound 1:H2:TADF15:E35 was 44.7% by mass:20% by mass:35% by mass:0.3% by mass.
Organic electroluminescence devices 6-2 and 6-3 were produced according to the same procedure except that compound 16 or compound 512 was used instead of compound 1.
A comparative element 6-1 was produced according to the same procedure except that the comparative compound 1 was used instead of the compound 1.
When electricity was applied to the electrodes of each of the fabricated devices, red delayed fluorescence was observed. For each element, the driving voltage was measured at a current density of 15.4 mA/cm ² , and the difference (relative value) from the driving voltage of the comparative element 6-1 was obtained. Table 5 shows the results.

As shown in Table 3, the devices 6-1 to 6-3 of the present invention exhibited lower drive voltages than the comparative device 6-1. From this, it was confirmed that the driving voltage is lowered even when the compound of the present invention is used together with the second host material, the delayed fluorescent material and the fluorescent material.

As described above, the organic electroluminescence device using the compound of the present invention exhibited a lower driving voltage, a longer device life, and a higher luminous efficiency than the devices using the comparative compounds 1-3. This is because the structure in which the substituted dibenzofuran-2-yl group and the group having a carbazole structure are arranged at the para-position of the benzene ring favorably functions as a host material or an electron blocking material.

The compound represented by general formula (1) is useful, for example, as a host material or electron barrier material. An organic light-emitting device using the compound represented by general formula (1) has excellent properties. Therefore, the present invention has high industrial applicability.

Claims

A compound represented by the following general formula (1).

[In the general formula (1),
R 1 to R 4 and R 8 to R 19 each independently represent a hydrogen atom, a deuterium atom, a substituted or unsubstituted aryl group, or a substituted or unsubstituted alkyl group;
R 5 to R 7 each independently represent a hydrogen atom, a deuterium atom, or a substituted or unsubstituted alkyl group;
at least one of R 1 to R 4 is a substituted or unsubstituted aryl group or a substituted or unsubstituted alkyl group;
R 12 and R 13 , R 13 and R 14 , R 14 and R 15 , R 16 and R 17 , R 17 and R 18 , R 18 and R 19 may combine with each other to form a cyclic structure. . ]
R 1 to R 4 and R 8 to R 19 are each independently a hydrogen atom, or one atom or group selected from the group consisting of a deuterium atom, an alkyl group and an aryl group, or a combination of two or more 2. The compound of claim 1, which is a group.
At least one of R 1 to R 4 is an aryl group optionally substituted with one atom or group selected from the group consisting of a deuterium atom, an alkyl group and an aryl group, or a group formed by combining two or more 2. The compound of claim 1, which is
2. The compound of Claim 1, wherein R2 is a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group.
2. The compound of claim 1, wherein at least one of R14 and R17 is a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group.
The compound according to claim 1, wherein the total number of benzene rings contained in R 1 to R 19 is 1 to 3.
The compound according to claim 1, wherein R 5 -R 7 are each independently a hydrogen atom or a deuterium atom.
at least one pair of R 12 and R 13 , R 13 and R 14 , R 14 and R 15 , R 16 and R 17 , R 17 and R 18 , R 18 and R 19 are bonded together to form a cyclic structure; 2. The compound of claim 1, which is formed.
A host material containing the compound according to any one of claims 1 to 8.
The host material according to claim 9 for use with a delayed fluorescence material.
An electron barrier material containing the compound according to any one of claims 1 to 8.
A composition in which the compound according to any one of claims 1 to 8 is doped with a delayed fluorescence material.
The composition according to claim 12, which is in the form of a film.
The composition according to claim 12, wherein the delayed fluorescence material is a compound having a cyanobenzene structure in which the benzene ring is substituted with one cyano group.
The composition according to claim 14, wherein the delayed fluorescence material has two or more substituted or unsubstituted carbazolyl groups bonded to the benzene ring in addition to the cyano group.
The composition according to claim 12, wherein the delayed fluorescence material is a compound having a dicyanobenzene structure in which two cyano groups are substituted on the benzene ring.
The composition according to claim 14, further comprising a fluorescent compound having a lowest excited singlet energy lower than that of the compound represented by the general formula (1) and the delayed fluorescent material.
The composition according to claim 12, further comprising a host material not represented by the general formula (1).
An organic light emitting device containing the compound according to any one of claims 1 to 8.
The organic light-emitting device according to claim 19, which has a layer made of the composition according to claim 12.
21. The organic light emitting device according to claim 20, wherein said layer consists only of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms, oxygen atoms, sulfur atoms, boron atoms and halogen atoms.
The organic light-emitting device according to claim 21, wherein the layer consists only of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms and oxygen atoms.
The organic light-emitting device according to claim 19, which is an organic electroluminescence device.