WO2022254965A1

WO2022254965A1 - Compound, light-emitting material, and light-emitting element

Info

Publication number: WO2022254965A1
Application number: PCT/JP2022/017166
Authority: WO
Inventors: 善丈鈴木; 正貴山下; 琢哉比嘉; 侑山根; 昇真田; 幸誠金原
Original assignee: 株式会社Kyulux
Priority date: 2021-06-03
Filing date: 2022-04-06
Publication date: 2022-12-08
Also published as: CN117396486A; JPWO2022254965A1; KR20240017808A

Abstract

This compound represented by the general formula is a light-emitting material having a short lifetime of delayed fluorescence. Two or three among R¹-R⁴ are donor groups, at least one of which is a ring-fused indol-1-yl group, one or two among R¹-R⁴ is/are an aryl group or a heteroaryl group, and the remaining R¹-R⁴ is a hydrogen atom or a deuterium atom.

Description

Compounds, luminescent materials and light-emitting devices

The present invention relates to a compound useful as a light-emitting material and a light-emitting device using the same.

Research to increase the luminous efficiency of light-emitting elements such as organic electroluminescence elements (organic EL elements) is being actively carried out. In particular, various attempts have been made to improve the luminous efficiency by newly developing and combining electron transporting materials, hole transporting materials, light emitting materials, and the like, which constitute organic electroluminescence elements. Among them, research on organic electroluminescence elements using delayed fluorescence materials can also be seen.

A delayed fluorescence material is a material that emits fluorescence when returning from the excited singlet state to the ground state after reverse intersystem crossing from the excited triplet state to the excited singlet state occurs in the excited state. Fluorescence by such a pathway is called delayed fluorescence because it is observed later than the fluorescence from the excited singlet state directly generated from the ground state (ordinary fluorescence). Here, for example, when a light-emitting compound is excited by carrier injection, the probability of occurrence of an excited singlet state and an excited triplet state is statistically 25%:75%. There is a limit to the improvement in luminous efficiency with only the fluorescence of . On the other hand, in the delayed fluorescence material, not only the excited singlet state but also the excited triplet state can be used for fluorescence emission through the reverse intersystem crossing described above, so the emission is higher than that of ordinary fluorescent materials. Efficiency will be obtained.

Since this principle was clarified, various delayed fluorescence materials have been discovered through various studies. However, a material that emits delayed fluorescence is not immediately useful as a light-emitting material. Among delayed fluorescence materials, there are those in which reverse intersystem crossing is relatively difficult to occur, and in which the lifetime of delayed fluorescence is long. In addition, there are some devices that accumulate excitons in a high current density region, resulting in a decrease in luminous efficiency, or rapidly degrade when driven for a long period of time. Therefore, the actual situation is that there are extremely many delayed fluorescence materials that have room for improvement in terms of practicality. Moreover, in recent years, the properties required for fluorescent materials have been increasing. Therefore, even excellent delayed fluorescence materials such as compounds having the following structures are required to further improve their properties (see Patent Document 1).

WO2019/004254

Until now, it is difficult to say that the relationship between the chemical structure and properties of delayed fluorescence materials has been sufficiently elucidated. Therefore, it is currently difficult to generalize the chemical structure of compounds useful as light-emitting materials, and there are many unclear points.

Under these circumstances, the present inventors conducted extensive research with the aim of providing compounds that are more useful as light-emitting materials for light-emitting devices. Then, intensive studies were carried out with the aim of deriving and generalizing the general formulas of compounds that are more useful as light-emitting materials.

As a result of intensive studies to achieve the above objectives, the present inventors found that among terephthalonitrile derivatives, compounds having a structure that satisfies specific conditions are useful as light-emitting materials. 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),
Two to three of R ¹ to R ⁴ each independently represent a donor group, at least one of which is an indol-1-yl group with condensed rings. The ring-fused indol-1-yl group forms a condensed ring having 4 or more rings by ring condensation with indole, and the condensed ring may be substituted.
1 to 2 of R ¹ to R ⁴ each independently represent a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group bonded via a carbon atom.
The remaining R ¹ to R ⁴ represent hydrogen atoms or deuterium atoms. ]
[2] two of R ¹ to R ⁴ are each independently a donor group, at least one of which is an indol-1-yl group to which the ring is condensed;
one of R ¹ to R ⁴ is a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group bonded at a carbon atom;
The compound according to [1], wherein the remaining R ¹ to R ⁴ are hydrogen atoms or deuterium atoms.
[3] two of R ¹ to R ⁴ are each independently a donor group, at least one of which is an indol-1-yl group to which the ring is condensed;
The compound according to [1], wherein two of R ¹ to R ⁴ are substituted or unsubstituted aryl groups or substituted or unsubstituted heteroaryl groups bonded at a carbon atom.
[4] three of R ¹ to R ⁴ are each independently a donor group, at least one of which is an indol-1-yl group to which the ring is condensed;
The compound according to [1], wherein one of R ¹ to R ⁴ is a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group bonded at a carbon atom.
[5] R ¹ and R ⁴ are each independently a donor group;
The compound according to any one of [1] to [4], wherein R ³ is a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group attached at a carbon atom.
[6] R ² and R ⁴ are each independently a donor group;
The compound according to any one of [1] to [4], wherein R ³ is a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group attached at a carbon atom.
[7] The compound according to any one of [1] to [6], wherein the condensed ring has 5 or more rings.
[8] The compound according to [7], wherein a carbon atom constituting the condensed ring skeleton having 4 or more rings is substituted with a substituted or unsubstituted aryl group.
[9] The compound according to [7], wherein the condensed ring skeleton having 4 or more rings contains a nitrogen atom, and the nitrogen atom is substituted with a substituted or unsubstituted aryl group.
[10] the ring condensed to the benzene ring constituting the indol-1-yl group is a substituted or unsubstituted furan ring, a substituted or unsubstituted thiophene ring, or a substituted or unsubstituted pyrrole ring; , The compound according to any one of [1] to [9], wherein the furan ring, the thiophene ring and the pyrrole ring may be further condensed with another ring.
[11] The compound according to any one of [1] to [10], wherein the indol-1-yl group to which the rings are condensed has any one of the following condensed rings.

[In each structure above, hydrogen atoms may be substituted, and rings may be condensed. ]
[12] The compound according to any one of [1] to [10], wherein the indol-1-yl group to which the rings are condensed has any one of the following condensed ring skeletons.

[In each structure above, hydrogen atoms may be substituted, and rings may be condensed. ]
[13] The indol-1-yl group to which the rings are condensed has a structure in which heterocycles are condensed at positions 4 and 5 of the indole ring, according to any one of [1] to [12]. Compound.
[14] The compound according to any one of [1] to [13], wherein Ar is a substituted or unsubstituted phenyl group or a substituted or unsubstituted pyridyl group.
[15] The compound according to any one of [1] to [14], consisting of atoms selected from the group consisting of carbon atoms, hydrogen atoms, deuterium atoms, nitrogen atoms, oxygen atoms and sulfur atoms.
[16] A luminescent material comprising the compound according to any one of [1] to [15].
[17] A light-emitting device comprising the compound according to any one of [1] to [15].
[18] The light-emitting device according to [17], wherein the light-emitting device has a light-emitting layer, and the light-emitting layer contains the compound and a host material.
[19] The light-emitting device according to [18], wherein the light-emitting device has a light-emitting layer, the light-emitting layer contains the compound and a light-emitting material, and emits light mainly from the light-emitting material.

The compound of the present invention is useful as a luminescent material. Further, the compounds of the present invention include compounds having a short delayed fluorescence lifetime. Furthermore, an organic light-emitting device using the compound of the present invention is useful because of its high device durability.

It is a schematic sectional drawing which shows the example of layer structure of an organic electroluminescent element.

The contents of the present invention will be described in detail below. Although the constituent elements described below may be described based on representative embodiments and specific examples of the present invention, 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 described before and after "-" as lower and upper limits. Also, some or all of the hydrogen atoms present in the molecule of the compound used in the present invention can be replaced with deuterium atoms ( ² H, deuterium D). In the chemical structural formulas of this specification, hydrogen atoms are indicated as H or omitted. For example, when the atoms bonded to the ring-skeleton-constituting carbon atoms of the benzene ring are omitted, it is assumed that H is bonded to the ring-skeleton-constituting carbon atoms where the display is omitted. Deuterium atoms are denoted as D in chemical structural formulas herein.

[Compound represented by general formula (1)]

Two to three of R ¹ to R ⁴ in general formula (1) each independently represent a donor group. At least one of the donor groups is a substituted or unsubstituted indol-1-yl group, and an indole ring constituting the indol-1-yl group is fused with a ring, thereby It forms a condensed ring with 4 or more rings. Hereinafter, a group satisfying this condition is referred to as a "ring-fused indol-1-yl group".

The ring-fused indol-1-yl group may be a polycyclic ring having one ring condensed to the benzene ring or pyrrole ring that constitutes the indol-1-yl group, or may have two or more polycyclic or monocyclic rings. may be For example, when two are condensed, it is preferable that one is condensed to a benzene ring and one is condensed to a pyrrole ring. Two condensed rings may be the same or different. By condensing a ring with an indole ring, a condensed ring having 4 or more, 5 or more, or 6 or more rings may be formed, and a condensed ring having 5 or more rings is preferably formed. For example, a compound having a condensed ring having 4 rings, a compound having a condensed ring having 5 rings, a compound having a condensed ring having 6 rings, and a condensed ring having 8 rings A compound forming a ring may be employed.
The ring may be fused only at the 2,3-position (b), only the 4,5-position (e) or only the 5,6-position (f) of the indole ring. may be condensed, may be condensed only at the 6,7-position (g), or may be condensed at both the 4,5-position (e) and the 6,7-position (g). In addition, any one of 4,5-position (e), 5,6-position (f) and 6,7-position (g) may be condensed at 2,3-position (b) (the following formula see, * indicates binding position).

A ring that is directly condensed to a benzene ring or pyrrole ring that constitutes an indol-1-yl group (when the condensed ring is polycyclic, only the ring that is directly condensed among the rings that constitute the polycyclic ring) is Any of an aromatic hydrocarbon ring, an aromatic heterocyclic ring, an aliphatic hydrocarbon ring, and an aliphatic heterocyclic ring may be used. Preferably, one or more rings selected from the group consisting of benzene rings and aromatic heterocycles are directly condensed.
A heterocycle as used herein is a ring containing a heteroatom. The heteroatoms are preferably selected from oxygen, sulfur, nitrogen and silicon atoms, more preferably from oxygen, sulfur and nitrogen atoms. In one preferred aspect, the heteroatom is an oxygen atom. In another preferred aspect, the heteroatom is a sulfur atom. In yet another preferred aspect, the heteroatom is a nitrogen atom. The number of hetero atoms contained as ring skeleton-constituting atoms of the hetero ring is 1 or more, preferably 1 to 3, more preferably 1 or 2. In one preferred embodiment, the number of heteroatoms is one. When the number of heteroatoms is two or more, they are preferably heteroatoms of the same type, but may be composed of heteroatoms of different types. For example, two or more heteroatoms may all be nitrogen atoms. Ring skeleton atoms other than heteroatoms are carbon atoms. The number of atoms constituting the ring skeleton constituting the hetero ring directly condensed to the benzene ring constituting the indol-1-yl group is preferably 4 to 8, more preferably 5 to 7, 5 or 6 is more preferred. In a preferred embodiment, the heterocyclic ring has 5 ring skeleton-constituting atoms. The hetero ring preferably has two or more conjugated double bonds, and the condensed hetero ring preferably expands the conjugated system of the indole ring (i.e., has aromaticity). is preferred). Preferred examples of heterocycles include furan rings, thiophene rings and pyrrole rings.
The ring directly condensed to the benzene ring or pyrrole ring constituting the indol-1-yl group may be further condensed with another ring. Moreover, the condensed ring may be a monocyclic ring or a condensed ring. Examples of condensed rings include aromatic hydrocarbon rings, aromatic heterocycles, aliphatic hydrocarbon rings, and aliphatic heterocycles.
In a preferred embodiment of the present invention, at least one hetero ring is directly condensed with the benzene ring or pyrrole ring that constitutes the indol-1-yl group. In a preferred embodiment of the present invention, the condensed rings that make up the condensed indol-1-yl group contain two or more heterocycles. For example, a case containing two heterocycles and a case containing three heterocycles can be exemplified.

A benzene ring can be mentioned as an aromatic hydrocarbon ring in the present specification. Aromatic heterocycles include furan ring, thiophene ring, pyrrole ring, pyridine ring, pyridazine ring, pyrimidine ring, pyrazine ring, triazine ring, pyrrole ring, pyrazole ring and imidazole ring. A cyclopentane ring, a cyclohexane ring, and a cycloheptane ring can be mentioned as the aliphatic hydrocarbon ring. Examples of aliphatic heterocycles include piperidine ring, pyrrolidine ring and imidazoline ring. Specific examples of condensed rings include naphthalene ring, anthracene ring, phenanthrene ring, pyran ring, tetracene ring, indole ring, isoindole ring, benzimidazole ring, benzotriazole ring, quinoline ring, isoquinoline ring, quinazoline ring, quinoxaline ring, and cinnoline. rings can be mentioned.

In a preferred embodiment of the invention, the ring-fused indol-1-yl group is a benzofuran-fused indol-1-yl group, a benzothiophene-fused indol-1-yl group, an indole-fused indol-1-yl group, or a sylindene-fused indol-1-yl group. -1-yl group. In a more preferred aspect of the invention, the indol-1-yl group is a benzofuran-fused indol-1-yl group, a benzothiophene-fused indol-1-yl group, or an indole-fused indol-1-yl group.

In the present invention, a substituted or unsubstituted benzofuro[2,3-e]indol-1-yl group can be employed as the benzofuran-fused indol-1-yl group. A substituted or unsubstituted benzofuro[3,2-e]indol-1-yl group can also be employed. A substituted or unsubstituted benzofuro[2,3-f]indol-1-yl group can also be employed. A substituted or unsubstituted benzofuro[3,2-f]indol-1-yl group can also be employed. A substituted or unsubstituted benzofuro[2,3-g]indol-1-yl group can also be employed. A substituted or unsubstituted benzofuro[3,2-g]indol-1-yl group can also be employed. The condensed rings constituting these groups may or may not be further condensed.
In the present invention, a substituted or unsubstituted benzofuro[2,3-a]carbazol-9-yl group can be employed as the benzofuran-fused indol-1-yl group. A substituted or unsubstituted benzofuro[3,2-a]carbazol-9-yl group can also be employed. A substituted or unsubstituted benzofuro[2,3-b]carbazol-9-yl group can also be employed. A substituted or unsubstituted benzofuro[3,2-b]carbazol-9-yl group can also be employed. A substituted or unsubstituted benzofuro[2,3-c]carbazol-9-yl group can also be employed. A substituted or unsubstituted benzofuro[3,2-c]carbazol-9-yl group can also be employed. The condensed rings constituting these groups may or may not be further condensed.
Preferred benzofuran-fused indol-1-yl groups include groups having any of the structures below, and hydrogen atoms in the structures below may or may not be substituted. For example, those substituted with an aryl group such as a phenyl group, or those substituted at the 3-position of the carbazole ring can be preferably exemplified. Further, the benzene ring in the structure below may or may not be condensed with another ring.

A carbazol-9-yl group in which two benzofuran rings are condensed at the 2 and 3 positions can also be employed. Specifically, it is a group having any of the structures below, and hydrogen atoms in the structures below may or may not be substituted. Further, the benzene ring in the structure below may or may not be condensed with another ring.

In the present invention, a substituted or unsubstituted benzothieno[2,3-e]indol-1-yl group can be employed as the benzothiophene-fused indol-1-yl group. A substituted or unsubstituted benzothieno[3,2-e]indol-1-yl group can also be employed. A substituted or unsubstituted benzothieno[2,3-f]indol-1-yl group can also be employed. A substituted or unsubstituted benzothieno[3,2-f]indol-1-yl group can also be employed. A substituted or unsubstituted benzothieno[2,3-g]indol-1-yl group can also be employed. A substituted or unsubstituted benzothieno[3,2-g]indol-1-yl group can also be employed. The condensed rings constituting these groups may or may not be further condensed.
In the present invention, a substituted or unsubstituted benzothieno[2,3-a]carbazol-9-yl group can be employed as the benzothiophene-fused indol-1-yl group. A substituted or unsubstituted benzothieno[3,2-a]carbazol-9-yl group can also be employed. A substituted or unsubstituted benzothieno[2,3-b]carbazol-9-yl group can also be employed. A substituted or unsubstituted benzothieno[3,2-b]carbazol-9-yl group can also be employed. A substituted or unsubstituted benzothieno[2,3-c]carbazol-9-yl group can also be employed. A substituted or unsubstituted benzothieno[3,2-c]carbazol-9-yl group can also be employed. The condensed rings constituting these groups may or may not be further condensed.
Preferred benzothiophene-fused indol-1-yl groups include groups having any of the structures below, and hydrogen atoms in the structures below may or may not be substituted. For example, those substituted with an aryl group such as a phenyl group, or those substituted at the 3-position of the carbazole ring can be preferably exemplified. Further, the benzene ring in the structure below may or may not be condensed with another ring.

A carbazol-9-yl group in which two benzothiophene rings are fused at the 2 and 3 positions can also be employed. Specifically, it is a group having any of the structures below, and hydrogen atoms in the structures below may or may not be substituted. Further, the benzene ring in the structure below may or may not be condensed with another ring.

In the present invention, a substituted or unsubstituted indolo[2,3-e]indol-1-yl group can be employed as the indole-fused indol-1-yl group. A substituted or unsubstituted indolo[3,2-e]indol-1-yl group can also be employed. A substituted or unsubstituted indolo[2,3-f]indol-1-yl group can also be employed. A substituted or unsubstituted indolo[3,2-f]indol-1-yl group can also be employed. A substituted or unsubstituted indolo[2,3-g]indol-1-yl group can also be employed. A substituted or unsubstituted indolo[3,2-g]indol-1-yl group can also be employed. The condensed rings constituting these groups may or may not be further condensed.
In the present invention, a substituted or unsubstituted indolo[2,3-a]carbazol-9-yl group can be employed as the indole-fused indol-1-yl group. A substituted or unsubstituted indolo[3,2-a]carbazol-9-yl group can also be employed. A substituted or unsubstituted indolo[2,3-b]carbazol-9-yl group can also be employed. A substituted or unsubstituted indolo[3,2-b]carbazol-9-yl group can also be employed. A substituted or unsubstituted indolo[2,3-c]carbazol-9-yl group can also be employed. A substituted or unsubstituted indolo[3,2-c]carbazol-9-yl group can also be employed. The condensed rings constituting these groups may or may not be further condensed.
Preferred indole-fused indol-1-yl groups include groups having any of the structures below, and hydrogen atoms in the structures below may or may not be substituted. For example, those substituted with an aryl group such as a phenyl group, or those substituted at the 3-position of the carbazole ring can be preferably exemplified. Further, the benzene ring in the structure below may or may not be condensed with another ring.

The "alkyl group" as used herein 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 group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, n-pentyl group, isopentyl group, n-hexyl group, isohexyl group, 2-ethylhexyl group, n-heptyl group, isoheptyl group, n-octyl group, isooctyl group, n-nonyl group, isononyl group, n-decanyl group, isodecanyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group. can. The alkyl group as a substituent may be further substituted with a deuterium atom, an aryl group, an alkoxy group, an aryloxy group, or a halogen atom.
An "alkenyl group" 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 alkenyl group can be, for example, 2 or more and 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 alkenyl groups include ethenyl, n-propenyl, isopropenyl, n-butenyl, isobutenyl, n-pentenyl, isopentenyl, n-hexenyl, isohexenyl, and 2-ethylhexenyl groups. can be mentioned. The alkenyl group as a substituent may be further substituted.
The “aryl group” and “heteroaryl group” may be monocyclic or condensed rings in which two or more rings are condensed. In the case of condensed rings, the number of condensed rings is preferably 2 to 6, and can be selected from 2 to 4, for example. Specific examples of rings include benzene ring, pyridine ring, pyrimidine ring, triazine ring, naphthalene ring, anthracene ring, phenanthrene ring, triphenylene ring, quinoline ring, pyrazine ring, quinoxaline ring, and naphthyridine ring. Specific examples of arylene group or heteroarylene group include phenyl group, 1-naphthyl group, 2-naphthyl group, 1-anthracenyl group, 2-anthracenyl group, 9-anthracenyl group, 2-pyridyl group, 3-pyridyl group, 4 - pyridyl group.
For the alkyl portion of the "alkoxy group" and "alkylthio group", the above description and specific examples of the alkyl group can be referred to. For the aryl moiety of the "aryloxy group" and "arylthio group", the above description and specific examples of the aryl group can be referred to. For the heteroaryl portion of the "heteroaryloxy group" and "heteroarylthio group", the above description and specific examples of the heteroaryl group can be referred to.
The ring-fused indol-1-yl group preferably has 16 or more atoms other than hydrogen atoms and deuterium atoms, more preferably 20 or more atoms, and can have, for example, 26 or more atoms. Also, it is preferably 80 or less, more preferably 50 or less, and even more preferably 30 or less.

In general formula (1), the number of ring-fused indol-1-yl groups selected from R ¹ to R ⁴ may be one, two, or three. . When there is only one ring-fused indol-1-yl group, there may be one donor group other than the ring-fused indol-1-yl group (hereinafter referred to as "another donor group"). and may be two. When there are two, they may be the same or different. When there are two ring-fused indol-1-yl groups, one or no other donor group may be present. When there are three ring-fused indol-1-yl groups, there are no other donor groups.
Other donor groups are groups with negative Hammett σp values. Here, "Hammet's σp value" is defined by L.P. P. Proposed by Hammett, it quantifies the effect of substituents on the reaction rate or equilibrium of para-substituted benzene derivatives. Specifically, the following formula holds between the substituents in the para-substituted benzene derivative and the reaction rate constant or equilibrium constant:
log(k/ _k0 ) = ρσp
or log(K/ _K0 ) = ρσp
is a constant (σp) specific to the substituents in . In the above formula, k is the rate constant of a benzene derivative without a substituent, _k0 is the rate constant of a benzene derivative substituted with a substituent, K is the equilibrium constant of a benzene derivative without a substituent, and _K0 is a substituent. The equilibrium constant of the benzene derivative substituted with ρ represents the reaction constant determined by the type and conditions of the reaction. For the description of the "Hammett's σp value" and the numerical value of each substituent in the present invention, refer to the description of the σp value in Hansch, C. et al., Chem. Rev., 91, 165-195 (1991). can. A group having a negative Hammett's σp value tends to exhibit electron-donating properties (donor properties), and a group having a positive Hammett's σp value tends to exhibit electron-withdrawing properties (acceptor properties).

Another donor group in the present invention is preferably a group containing a substituted amino group. The substituent bonded to the nitrogen atom of the amino group is preferably a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group. , a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group. The substituted amino group is particularly preferably a substituted or unsubstituted diarylamino group or a substituted or unsubstituted diheteroarylamino group. Two aryl groups constituting the diarylamino group herein may be bonded to each other, and two heteroaryl groups constituting the diheteroarylamino group may be bonded to each other. The other donor group in the present invention may be a group that binds through the nitrogen atom of the substituted amino group, or a group that binds through the group to which the substituted amino group is bound. The group to which the substituted amino group is bonded is preferably a π-conjugated group. More preferred are groups attached at the nitrogen atom of a substituted amino group.
A substituted or unsubstituted carbazol-9-yl group is particularly preferred as another donor group in the present invention. The two benzene rings that make up the carbazol-9-yl group are not condensed. Substituents for the carbazol-9-yl group include alkyl groups, alkenyl groups, aryl groups, heteroaryl groups, alkoxy groups, alkylthio groups, aryloxy groups, arylthio groups, heteroaryloxy groups, heteroarylthio groups, and substituted amino groups. groups, and preferred substituents include alkyl groups, aryl groups, and substituted amino groups. For a description of substituted amino groups, reference can be made to the description in the previous paragraph. The substituted amino group here includes a substituted or unsubstituted carbazolyl group, such as a substituted or unsubstituted carbazol-3-yl group and a substituted or unsubstituted carbazol-9-yl group.
Other donor groups in the present invention preferably have 8 or more atoms other than hydrogen atoms and deuterium atoms, more preferably 12 or more atoms, and can also have, for example, 16 or more atoms. Also, it is preferably 80 or less, more preferably 60 or less, and even more preferably 40 or less.

In a preferred embodiment of the present invention, the ring-fused indol-1-yl group is limited to those containing two or more heterocycles in the condensed rings constituting the group, and other donor groups are defined as “other "donor group". Examples of condensed rings containing two or more heterocycles include D13 to D152 described later.
In another preferred embodiment of the present invention, the ring-fused indol-1-yl group is limited to those in which at least one heterocyclic ring is directly fused to the benzene ring or pyrrole ring of the indole, and other donor properties The group is referred to as "another donor group".

Specific examples of donor groups that ^D1 and ^D2 in formula (1) can take are shown below. D7 to D152 are specific examples of ring-fused indol-1-yl groups, and D1 to D6 are specific examples of other donor groups. In the following structural formulas, Ph represents a phenyl group and * represents a bonding position. In addition, CH ₃ is omitted from the methyl group, and for example, D2 represents a 3-methylcarbazol-9-yl group.

Those in which all hydrogen atoms in D1 to D152 are replaced with deuterium atoms are disclosed here as D1d to D152d.
Further, D31d1 to D42d1 obtained by substituting the phenyl group represented by "Ph" in D31 to D42 and D61 to D79 with a pentadeuteriophenyl group (a group in which all the hydrogen atoms of the phenyl group are substituted with deuterium atoms) and D61d1-D79d1.

1 to 2 of R ¹ to R ⁴ in general formula (1) each independently represent a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group bonded via a carbon atom. Among R ¹ to R ⁴ , those which are not a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group bonded via a carbon atom, or a ring-fused indol-1-yl group are hydrogen atoms or deuterium atoms. represents an atom, which can be, for example, a hydrogen atom.
Only one of R ¹ to R ⁴ may be a substituted or unsubstituted aryl group, and only one of R ¹ to R ⁴ is a substituted or unsubstituted hetero group attached at a carbon atom. It may be an aryl group. Two of R ¹ to R ⁴ may be the same substituted or unsubstituted aryl group or different substituted or unsubstituted aryl groups. Two of R ¹ to R ⁴ may be the same substituted or unsubstituted heteroaryl group, or may be different substituted or unsubstituted heteroaryl groups. One of R ¹ to R ⁴ may be a substituted or unsubstituted aryl group and the other one may be a substituted or unsubstituted heteroaryl group bonded via a carbon atom. In a preferred embodiment of the present invention, only one of R ¹ to R ⁴ is a substituted or unsubstituted aryl group, or two of R ¹ to R ⁴ are each independently substituted or unsubstituted aryl is the base. According to the present invention, by adopting Ar as a substituent, the _ΔEST (difference between the lowest excited singlet energy and the lowest excited triplet energy) of the donor-substituted terephthalonitrile is reduced, and the usefulness as a delayed phosphor (luminous efficiency, etc.) can be improved.

For the description and preferred range of the aryl group and heteroaryl group that R and Ar can take, the description of the aryl group and heteroaryl group in the substituents of the ring-fused indol-1-yl group can be referred to. However, a heteroaryl group is a heteroaryl group attached at a carbon atom. The aryl group substituents and the heteroaryl group substituents include alkyl groups, alkenyl groups, aryl groups, heteroaryl groups, alkoxy groups, alkylthio groups, aryloxy groups, arylthio groups, heteroaryloxy groups, and heteroarylthio groups. , cyano groups, and combinations of these groups. Preferred groups of substituents include alkyl groups, aryl groups, alkoxy groups, alkylthio groups, and cyano groups. In one preferred aspect of the invention, the aryl and heteroaryl groups are substituted with alkyl groups or unsubstituted. Examples include an unsubstituted phenyl group and a phenyl group substituted with an alkyl group.

Specific examples of the substituted or unsubstituted aryl group and the substituted or unsubstituted heteroaryl group bonded to the carbon atom that Ar in the general formula (1) can take are shown below. In the structural formulas below, t-Bu represents a tertiary butyl group and * represents a bonding position.

Ar1d to Ar81d in which all the hydrogen atoms of Ar1 to Ar81 are replaced with deuterium atoms are disclosed here.

The compound represented by the general formula (1) preferably does not contain a metal atom, and consists only of atoms selected from the group consisting of a carbon atom, a hydrogen atom, a deuterium atom, a nitrogen atom, an oxygen atom and a sulfur atom. It may be a compound that is In a preferred embodiment of the present invention, the compound represented by general formula (1) is composed only of atoms selected from the group consisting of carbon atoms, hydrogen atoms, deuterium atoms, nitrogen atoms and oxygen atoms. Further, the compound represented by general formula (1) may be a compound composed only of atoms selected from the group consisting of carbon atoms, hydrogen atoms, deuterium atoms, nitrogen atoms and sulfur atoms. The compound represented by general formula (1) may be a compound composed only of atoms selected from the group consisting of carbon atoms, hydrogen atoms, deuterium atoms and nitrogen atoms. The compound represented by general formula (1) may be a compound composed only of atoms selected from the group consisting of carbon atoms, hydrogen atoms and nitrogen atoms. Furthermore, the compound represented by general formula (1) may be a compound containing no hydrogen atom and containing a deuterium atom. For example, the compound represented by general formula (1) may be a compound composed only of atoms selected from the group consisting of carbon atoms, deuterium atoms, nitrogen atoms, oxygen atoms and sulfur atoms.
In one aspect of the present invention, the compound represented by general formula (1) has a symmetrical structure. For example, it may have a line-symmetrical structure or a rotationally-symmetrical structure.

Specific examples of the compounds represented by the general formula (1) are shown in Tables 1 to 6 below. Tables 1 to 6 show the structures of compounds by specifying D ¹ , D ² , D ³ , Ar, Ar ¹ and Ar ² for each compound. For example, in compounds 1-125 of Table 1, Ar is fixed to Ar1 and D ¹ has the same structure as D ² . Compounds 1 to 125 are those in which D ¹ and D ² are D7 to D20, D22 to D30, D36 to D48, D50 to D60, D67 to D73, and D79 to D149 in this order. Compounds 856 to 2451 where D ¹ is D ² is D21, and Ar is Ar2 to Ar21, Ar25 to Ar52, and Ar54 to Ar81 in that order are compounds 856 to 931, and D ¹ is D ² is D31 wherein Ar is Ar2 to Ar21, Ar25 to Ar52, and Ar54 to Ar81 are numbered in order as compounds 931 to 1006, and finally ^D1 is ^D2 is D152, Compounds 2376 to 2451 are those in which Ar is Ar2 to Ar21, Ar25 to Ar52, and Ar54 to Ar81 in order. In Tables 1-6, compounds 1-25053 are individually identified in structure and specifically disclosed herein. Compounds 1d to 25053d in which all hydrogen atoms present in the molecules of compounds 1 to 25053 are replaced with deuterium atoms are also disclosed. It should be noted that when rotamers of the following compounds exist, the mixture of rotamers as well as each separate rotamer are also disclosed herein. In Tables 1 to 6 below, Ar82 represents the same structure as Ar1d (a structure in which all hydrogen atoms of Ar1 are replaced with deuterium atoms).

The molecular weight of the compound represented by the general formula (1) is, for example, 1500 or less when the organic layer containing the compound represented by the general formula (1) is intended to be formed by a vapor deposition method and used. It is preferably 1200 or less, more preferably 1000 or less, and even more preferably 900 or less. The lower limit of the molecular weight is the molecular weight of the smallest compound represented by general formula (1).
The compound represented by general formula (1) may be formed into a film by a coating method regardless of its molecular weight. If a coating method is used, it is possible to form a film even with a compound having a relatively large molecular weight. Among cyanobenzene compounds, the compound represented by the general formula (1) has the advantage of being easily dissolved in an organic solvent. Therefore, the compound represented by the general formula (1) can be easily applied to the coating method, and can be easily purified to increase its purity.
Since the compound represented by the general formula (1) has a short delayed fluorescence lifetime (τ2), it can improve the luminous efficiency of the organic light-emitting device and suppress roll-off. Therefore, it is possible to provide an organic light-emitting device that is efficient and excellent in stability (durability).

By applying the present invention, it is also conceivable to use a compound containing a plurality of structures represented by general formula (1) in its molecule as a light-emitting material.
For example, it is conceivable that a polymerizable group is preliminarily present in the structure represented by the general formula (1), and a polymer obtained by polymerizing the polymerizable group is used as the light-emitting material. Specifically, by preparing a monomer containing a polymerizable functional group in any one of R ¹ to R ⁴ of general formula (1) and polymerizing it alone or copolymerizing it with other monomers, It is conceivable to obtain a polymer having repeating units and use the polymer as a light-emitting material. Alternatively, it is conceivable to obtain a dimer or trimer by coupling compounds having a structure represented by general formula (1) and use them as a light-emitting material.

Examples of polymers having repeating units containing the structure represented by general formula (1) include polymers containing structures represented by the following general formula (2) or (3).

In general formula (2) or (3), Q represents a group containing the structure represented by general formula (1), and L ¹ and L ² represent linking groups. The number of carbon atoms in the linking group is preferably 0-20, more preferably 1-15, still more preferably 2-10. The linking group preferably has a structure represented by -X ¹¹ -L ¹¹ -. Here, X ¹¹ represents an oxygen atom or a sulfur atom, preferably an oxygen atom. L ¹¹ represents a linking group, preferably a substituted or unsubstituted alkylene group or a substituted or unsubstituted arylene group, a substituted or unsubstituted alkylene group having 1 to 10 carbon atoms, or a substituted or unsubstituted A phenylene group is more preferred.
In general formula (2) or (3), R ¹⁰¹ , R ¹⁰² , R ¹⁰³ and R ¹⁰⁴ each independently represent a substituent. Preferred are substituted or unsubstituted alkyl groups having 1 to 6 carbon atoms, substituted or unsubstituted alkoxy groups having 1 to 6 carbon atoms, and halogen atoms, more preferably unsubstituted alkyl groups having 1 to 3 carbon atoms. , an unsubstituted alkoxy group having 1 to 3 carbon atoms, a fluorine atom or a chlorine atom, more preferably an unsubstituted alkyl group having 1 to 3 carbon atoms or an unsubstituted alkoxy group having 1 to 3 carbon atoms.
The linking groups represented by L ¹ and L ² can be bonded to any of R ¹ to R ⁴ constituting Q in general formula (1). Two or more linking groups may be linked to one Q to form a crosslinked structure or network structure.

Specific structural examples of the repeating unit include structures represented by the following formulas (4) to (7).

Polymers having repeating units containing these formulas (4) to (7) are obtained by introducing a hydroxy group into any of R ¹ to R ⁴ in general formula (1), and using it as a linker, the following compounds are prepared. It can be synthesized by reacting to introduce a polymerizable group and polymerizing the polymerizable group.

The polymer containing the structure represented by general formula (1) in the molecule may be a polymer consisting only of repeating units having the structure represented by general formula (1), or may have other structures. It may be a polymer containing a repeating unit having Moreover, the repeating unit having the structure represented by the general formula (1) contained in the polymer may be of a single type, or may be of two or more types. Examples of repeating units having no structure represented by general formula (1) include those derived from monomers used in ordinary copolymerization. Examples thereof include repeating units derived from monomers having ethylenically unsaturated bonds such as ethylene and styrene.

In one embodiment, the compound represented by general formula (1) is a luminescent material.
In one embodiment, the compound represented by general formula (1) is a compound capable of emitting delayed fluorescence.
In certain embodiments of the present disclosure, the compound represented by general formula (1), when excited by thermal or electronic means, is in the UV region, blue, green, yellow, orange, red region of the visible spectrum (eg, about 420 nm to about 500 nm, about 500 nm to about 600 nm, or about 600 nm to about 700 nm) or can emit light in the near-infrared region.
In certain embodiments of the present disclosure, compounds represented by general formula (1), when excited by thermal or electronic means, exhibit a red or orange region of the visible spectrum (e.g., about 620 nm to about 780 nm, about 650 nm).
In certain embodiments of the present disclosure, compounds represented by general formula (1), when excited by thermal or electronic means, exhibit an orange or yellow region of the visible spectrum (e.g., about 570 nm to about 620 nm, about 590 nm, about 570 nm).
In certain embodiments of the present disclosure, the compound represented by general formula (1) is in the green region of the visible spectrum (eg, about 490 nm to about 575 nm, about 510 nm) when excited by thermal or electronic means. Can emit light.
In certain embodiments of the present disclosure, the compound represented by general formula (1) is in the blue region of the visible spectrum (eg, about 400 nm to about 490 nm, about 475 nm) when excited by thermal or electronic means. Can emit light.
In certain embodiments of the present disclosure, compounds of general formula (1) are capable of emitting light in the ultraviolet spectral region (eg, 280-400 nm) when excited by thermal or electronic means.
In certain embodiments of the present disclosure, compounds of general formula (1) are capable of emitting light in the infrared spectral region (eg, 780 nm-2 μm) when excited by thermal or electronic means.

Electronic properties of small molecule chemical substance libraries can be calculated using known ab initio quantum chemical calculations. For example, the Hartree-Fock equations using time-dependent density functional theory with 6-31G* as the basis and a family of functions known as Becke's three-parameter, Lee-Yang-Parr hybrid functionals (TD-DFT/B3LYP/6-31G*) can be analyzed to screen for molecular fragments (parts) with HOMO above a certain threshold and LUMO below a certain threshold.
Thereby, for example, the donor moiety (“D”) can be selected when there is a HOMO energy (eg, ionization potential) of −6.5 eV or higher. Also for example, acceptor moieties (“A”) can be selected when there is a LUMO energy (eg, electron affinity) of −0.5 eV or less. The bridging moiety (“B”) is, for example, a strongly conjugated system that can tightly constrain the acceptor and donor moieties to specific conformations, thereby allowing overlap between the π-conjugated systems of the donor and acceptor moieties. to prevent
In some embodiments, compound libraries are screened using one or more of the following properties.
1. Emission around a specific wavelength2. Calculated triplet states above a particular energy level;3. _ΔEST values below a specified value;4. quantum yield above a specified value;5. HOMO level6. LUMO Level In some embodiments, the difference between the lowest singlet excited state and the lowest triplet excited state at 77 K (ΔE _ST ) is less than about 0.5 eV, less than about 0.4 eV, less than about 0.3 eV, less than about 0.2 eV or less than about 0.1 eV. In some embodiments, the _ΔEST value is less than about 0.09 eV, less than about 0.08 eV, less than about 0.07 eV, less than about 0.06 eV, less than about 0.05 eV, less than about 0.04 eV, less than about 0.03 eV. , less than about 0.02 eV or less than about 0.01 eV.
In certain embodiments, the compound represented by general formula (1) comprises more than 25% of , about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, about 95% or more.

[Method for Synthesizing Compound Represented by Formula (1)]
The compound represented by general formula (1) is a novel compound.
The compound represented by general formula (1) can be synthesized by combining known reactions. For example, a (hetero)aryldifluoroterephthalonitrile substituted with a fluorine atom at the position where the donor group D ¹ or D ² is to be introduced is treated with D ¹ -H or D ² -H in tetrahydrofuran in the presence of sodium hydride. It is possible to synthesize by reacting. When D ¹ and D ² are different from each other, the reaction with D ¹ —H and D ² —H may be carried out in two steps. Specific reaction conditions and reaction procedures can be referred to Examples described later.

[Construction using compound represented by general formula (1)]
In one embodiment, a compound represented by general formula (1) is combined with, dispersed with, covalently bonded with, coated with, supported with, or associated with the compound 1 Used with one or more materials (eg, small molecules, polymers, metals, metal complexes, etc.) to form a solid film or layer. For example, a compound represented by general formula (1) can be combined with an electroactive material to form a film. In some cases, compounds of general formula (1) may be combined with hole-transporting polymers. In some cases, a compound of general formula (1) may be combined with an electron transport polymer. In some cases, compounds of general formula (1) may be combined with hole-transporting and electron-transporting polymers. In some cases, compounds of general formula (1) may be combined with copolymers having both hole-transporting and electron-transporting moieties. According to the above embodiments, electrons and/or holes formed in the solid film or layer can interact with the compound represented by general formula (1).

[Film formation]
In some embodiments, films comprising compounds of the present invention represented by general formula (1) can be formed in a wet process. In the wet process, a solution of a composition containing a compound of the invention is applied to the surface and a film is formed after removal of 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 wet processes, suitable organic solvents are selected and used that are capable of dissolving compositions containing the compounds of the present invention. In certain embodiments, compounds included in the composition can be introduced with substituents (eg, alkyl groups) that increase their solubility in organic solvents.
In some embodiments, films comprising compounds of the invention can be formed in a dry process. In some embodiments, the dry process can be vacuum deposition, but is not limited to this. When a vacuum deposition method is employed, the compounds forming the film may be co-deposited from separate deposition sources, or may be co-deposited from a single deposition source in which the compounds are mixed. When a single vapor deposition source is used, a mixed powder obtained by mixing powders of compounds may be used, a compression molding obtained by compressing the mixed powder may be used, or each compound may be heated, melted, and cooled. Mixtures may also be used. In one embodiment, the composition ratio of the plurality of compounds contained in the vapor deposition source is reduced by performing 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. can form a film with 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 a vapor deposition 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.

[Example of use of compound represented by general formula (1)]
Organic Light Emitting Diode:
One aspect of the present invention relates to use of the compound represented by general formula (1) of the present invention as a light-emitting material for an organic light-emitting device. In one embodiment, the compound represented by general formula (1) of the present invention can be effectively used as a light-emitting material in the light-emitting layer of an organic light-emitting device. In one embodiment, the compound represented by general formula (1) contains delayed fluorescence that emits delayed fluorescence (delayed phosphor). In one embodiment, the present invention provides a delayed phosphor having a structure represented by general formula (1). In one embodiment, the present invention relates to the use of compounds represented by general formula (1) as delayed phosphors. In one embodiment, the present invention provides that the compound represented by general formula (1) can be used as a host material and can be used with one or more luminescent materials, wherein the luminescent material is a fluorescent material, It can be a phosphorescent material or TADF. In one embodiment, the compound represented by general formula (1) can also be used as a hole transport material. In one embodiment, the compound represented by general formula (1) can be used as an electron transport material. In one embodiment, the present invention relates to a method for producing delayed fluorescence from a compound represented by general formula (1). In one embodiment, an organic light-emitting device containing a compound as a light-emitting material emits delayed fluorescence and exhibits high light emission efficiency.
In one embodiment, the emissive layer comprises a compound represented by general formula (1), and the compound represented by general formula (1) is oriented parallel to the substrate. In some embodiments, the substrate is a film-forming surface. In some embodiments, the orientation of the compounds of general formula (1) with respect to the film-forming surface affects or dictates the direction of propagation of light emitted by the aligning compounds. In some embodiments, aligning the propagation direction of light emitted by compounds represented by general formula (1) improves light extraction efficiency from the emissive layer.
One aspect of the present invention relates to an organic light emitting device. In some embodiments, the organic light emitting device includes an emissive layer. In one embodiment, the light-emitting layer contains a compound represented by general formula (1) as a light-emitting material. In one embodiment, the organic light emitting device is an organic photoluminescent device (organic PL device). In one embodiment, the organic light-emitting device is an organic electroluminescent device (organic EL device). In one embodiment, the compound represented by general formula (1) assists (as a so-called assist dopant) the light emission of other light-emitting materials contained in the light-emitting layer. In one embodiment, the compound represented by general formula (1) contained in the light-emitting layer is at its lowest excited singlet energy level and is at the lowest excited singlet energy level of the host material contained in the light-emitting layer. It is contained between the lowest excited singlet energy levels of other light-emitting materials contained in the light-emitting layer.
In some embodiments, the organic photoluminescent device includes at least one emissive layer. In one embodiment, an organic electroluminescent device includes at least an anode, a cathode, and an organic layer between said anode and said cathode. In some embodiments, the organic layers include at least the emissive layer. In some embodiments, the organic layers include only the emissive layer. In some embodiments, the organic layers include one or more organic layers in addition to the emissive layer. Examples of organic layers include hole transport layers, hole injection layers, electron blocking layers, hole blocking layers, electron injection layers, electron transport layers and exciton blocking layers. In some embodiments, the hole transport layer may be a hole injection transport layer with hole injection functionality, and the electron transport layer may be an electron injection transport layer with electron injection functionality. An example of an organic electroluminescence device is shown in FIG.

Luminous layer:
In some embodiments, the emissive layer is the layer in which holes and electrons injected from the anode and cathode, respectively, recombine to form excitons. In some embodiments, the layer emits light.
In some embodiments, only emissive materials are used as emissive layers. In some embodiments, the emissive layer includes an emissive material and a host material. In some embodiments, the emissive material is one or more compounds of general formula (1). In one embodiment, singlet and triplet excitons generated in the luminescent material are confined within the luminescent material to improve the light emission efficiency of the organic electroluminescent and organic photoluminescent devices. In some embodiments, a host material is used in addition to the emissive material in the emissive layer. In some embodiments, the host material is an organic compound. In certain embodiments, the organic compound has excited singlet energies and excited triplet energies, at least one of which is higher than those of the light-emitting materials of the present invention. In certain embodiments, the singlet and triplet excitons generated in the luminescent material of the invention are confined within the molecules of the luminescent material of the invention. In certain embodiments, singlet and triplet excitons are sufficiently confined to improve light emission efficiency. In certain embodiments, singlet and triplet excitons are not sufficiently confined, although high light emission efficiency can still be obtained, i.e., host materials that can achieve high light emission efficiency are particularly limited. can be used in the present invention without In some embodiments, light emission occurs in the emissive material in the emissive layer of the device of the invention. In some embodiments, emitted light includes both fluorescence and delayed fluorescence. In some embodiments, the emitted light includes emitted light from the host material. In some embodiments, the emitted light consists of emitted light from the host material. In one embodiment, the emitted light includes emitted light from the compound represented by general formula (1) and emitted light from the host material. In some embodiments, a TADF molecule and a host material are used. In some embodiments, TADF is an assisting dopant.

When the compound represented by formula (1) is used as the assist dopant, various compounds can be employed as the luminescent material (preferably fluorescent material). Examples of such luminescent materials 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. , terphenylene derivatives, fluoranthene derivatives, amine derivatives, quinacridone derivatives, oxadiazole derivatives, malononitrile derivatives, pyran derivatives, carbazole derivatives, julolidine derivatives, thiazole derivatives, derivatives containing metals (Al, Zn), and the like. be. These exemplified skeletons may or may not have a substituent. Also, these exemplary skeletons may be combined.
Examples of light-emitting materials that can be used in combination with the assist dopant represented by the general formula (1) are given below.

In addition, the compounds described in paragraphs 0220 to 0239 of WO2015/022974 can also be particularly preferably employed as the luminescent material used together with the assist dopant represented by general formula (1).

In one embodiment, when a host material is used, the amount of the compound of the present invention as the light-emitting material contained in the light-emitting layer is 0.1% by weight or more. In one embodiment, when a host material is used, the amount of the compound of the present invention as the light-emitting material contained in the light-emitting layer is 1% or more by weight. In one embodiment, when a host material is used, the amount of the compound of the present invention as the light-emitting material contained in the light-emitting layer is 50% by weight or less. In one embodiment, when a host material is used, the amount of the compound of the present invention as the light-emitting material contained in the light-emitting layer is 20% by weight or less. In one embodiment, when a host material is used, the amount of the compound of the invention as the light-emitting material contained in the light-emitting layer is 10% by weight or less.
In some embodiments, the host material of the emissive layer is an organic compound with hole-transporting and electron-transporting functionality. In some embodiments, the host material of the emissive layer is an organic compound that prevents the wavelength of emitted light from increasing. In some embodiments, the host material of the emissive layer is an organic compound with a high glass transition temperature.

In some embodiments, the host material is selected from the group consisting of:

In some embodiments, the emissive layer comprises two or more structurally different TADF molecules. For example, the light-emitting layer can be made to contain three kinds of materials in which the excited singlet energy level is higher in the order of the host material, the first TADF molecule, and the second TADF molecule. At this time, for both the first TADF molecule and the second TADF molecule, the difference _ΔEST between the lowest excited singlet energy level and the lowest excited triplet energy level at 77K is preferably 0.3 eV or less, and 0.25 eV or less. more preferably 0.2 eV or less, more preferably 0.15 eV or less, even more preferably 0.1 eV or less, and even more preferably 0.07 eV or less , is more preferably 0.05 eV or less, even more preferably 0.03 eV or less, and particularly preferably 0.01 eV or less. The content of the first TADF molecules in the light-emitting layer is preferably higher than the content of the second TADF molecules. Also, the content of the host material in the light-emitting layer is preferably higher than the content of the second TADF molecules. The content of the first TADF molecules in the light-emitting layer may be greater than, less than, or the same as the content of the host material. In some embodiments, the composition within the emissive layer may be 10-70% by weight of the host material, 10-80% by weight of the first TADF molecule, and 0.1-30% by weight of the second TADF molecule. In some embodiments, the composition within the emissive layer may be 20-45% by weight of the host material, 50-75% by weight of the first TADF molecule, and 5-20% by weight of the second TADF molecule. In one embodiment, the light emission quantum yield φPL1 (A) by photoexcitation of the co-deposited film of the first TADF molecule and the host material (the content of the first TADF molecule in this co-deposited film = A wt%), the second TADF molecule and the host The emission quantum yield φPL2(A) by photoexcitation of the co-evaporated film of the material (the content of the second TADF molecules in this co-evaporated film=A weight %) satisfies the relational expression φPL1(A)>φPL2(A). In one embodiment, the emission quantum yield φPL2(B) by photoexcitation of the co-deposited film of the second TADF molecule and the host material (the content of the second TADF molecule in this co-deposited film=B wt %) and the second TADF molecule alone The luminescence quantum yield φPL2(100) due to optical excitation of the film satisfies the relational expression φPL2(B)>φPL2(100). In some embodiments, the emissive layer can include three structurally different TADF molecules. The compound of the present invention can be any of a plurality of TADF compounds contained in the emissive layer.
In some embodiments, the emissive layer can be composed of materials selected from the group consisting of host materials, assisting dopants, and emissive materials. In some embodiments, the emissive layer does not contain metallic elements. In some embodiments, the emissive layer can be composed of a material consisting only of atoms selected from the group consisting of carbon atoms, hydrogen atoms, deuterium atoms, nitrogen atoms, oxygen atoms and sulfur atoms. Alternatively, the light-emitting layer can be composed of a material composed only of atoms selected from the group consisting of carbon atoms, hydrogen atoms, deuterium atoms, nitrogen atoms and oxygen atoms. Alternatively, the light-emitting layer can be composed of a material composed only of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms and oxygen atoms.
When the light-emitting layer contains a TADF material other than the compounds of the present invention, the TADF material may be a known delayed fluorescence material. Preferred delayed fluorescence materials include paragraphs 0008 to 0048 and 0095 to 0133 of WO2013/154064, paragraphs 0007 to 0047 and 0073 to 0085 of WO2013/011954, and 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, Paragraphs 0007 to 0032 and 0079 to 0084 of WO2013/133359, 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, paragraphs 0013 to 0025 of JP-A-2017-119663, paragraphs 0013-0026 of JP-A-2017-119664, paragraph 0012 of JP-A-2017-222623 ~ 0025, paragraphs 0010 to 0050 of JP 2017-226838, paragraphs 0012 to 0043 of JP 2018-100411, compounds included in the general formula described in paragraphs 0016 to 0044 of WO2018/047853 , particularly exemplified compounds, which are capable of emitting delayed fluorescence. Further, here, JP 2013-253121, WO2013/133359, WO2014/034535, WO2014/115743, WO2014/122895, WO2014/126200, WO2014/136758, WO2014 /133121, WO2014/136860, WO2014/196585, WO2014/189122, WO2014/168101, WO2015/008580, WO2014/203840, WO2015/002213, WO020213 Publications, WO2015/019725, WO2015/072470, WO2015/108049, WO2015/080182, WO2015/072537, WO2015/080183, JP 2015-129240, WO2014/12971 Publications, WO2015/129715, WO2015/133501, WO2015/136880, WO2015/137244, WO2015/137202, WO2015/137136, WO2015/146541, WO2015/159 A light-emitting material that can emit delayed fluorescence can be preferably employed. The above publications mentioned in this paragraph are hereby incorporated by reference as part of this specification.

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.

Preferred examples of compounds that can be used as the electron injection material are given below.

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 diffusion of excitons generated through recombination of holes and electrons in the light emitting layer 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 transport layer comprises a hole transport 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. is 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 is configured to emit light, wherein the at least one OLED includes at least one organic layer including an anode, a cathode, and a light-emitting layer between the anode and the cathode; at least one OLED comprising
a housing for the circuit board;
at least one connector located 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. Further, 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, and The applied organic film is made of the same material as that 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 with 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 another surface of a base substrate made of polyimide before forming a barrier layer on the other 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 described more specifically with reference to 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 spectrometer. (Ocean Optics: USB2000), a spectroradiometer (Topcon: SR-3) and a streak camera (Hamamatsu Photonics, Model C4334).
In the following examples, compounds included in general formula (1) were synthesized.

(Example 1)

Under nitrogen atmosphere, 2,6-difluoro-3-phenyl-1,4-benzenedicarbonitrile (0.32 g, 2.0 mmol), 5,8-dihydro-5-phenylindolo[3,2-c] A solution of carbazole (0.91 g, 4.3 mmol) and Cs ₂ CO ₃ (1.75 g, 8.33 mmol) in dimethylformamide (15 mL) was stirred at 150° C. for 14 hours. Then, the temperature was returned to room temperature, and the reaction was stopped with water and methanol. The resulting precipitate was filtered and purified by column chromatography (toluene/hexane/CHCl ₃ =8/1/1) and reprecipitation (CHCl ₃ /MeOH) to yield an orange solid (0.86 g, 0.99 mmol, 49%).
¹ H NMR (400MHz, CDCl ₃ , d): 8.36-8.29 (m, 2H), 8.24-8.13 (m, 3H), 7.72-7.56 (m, 10H), 7.42-7.38 (m, 10H), 7.46- 7.02 (m, 7H), 6.94-6.86 (m, 1H) 6.79-6.73 (m, 1H), 5.94 (d, J=8.0Hz, 1H), 5.79 (d,J=8.0Hz, 1H).
MS (ASAP): 865.47 [M+H] ⁺ calculated value C62H36N6: 864.30

(Example 2)

Synthesized in the same manner as in Example 1, the yield was 25%.
¹ H NMR (400MHz, CDCl ₃ , d): 8.98 (d, J = 8.0 Hz, 1H), 8.92 (d, J = 7.6 Hz, 1H), 8.82 (t, J = 7.6 Hz, 2H), 8.23 ( s, 1H), 7.68-7.40 (m, 25H), 7.21-7.14 (m, 4H), 7.10-7.01 (m, 3H).
MS (ASAP): 865.37 [M+H] ⁺ calculated value C62H36N6: 864.30

(Example 3)

Synthesized in the same manner as in Example 1, the yield was 50%.
¹ H NMR (400MHz, _CDCl3 , d): 8.87-8.83 (m, 4H), 7.66-7.59 (m, 8H), 7.55-7.42 (m, 14H), 7.33-7.28 (m, 2H), 7.17- 7.15 (m, 4H), 7.06-6.96 (m, 6H).
MS (ASAP): 941.46 [M+H] ⁺ calculated value C68H40N6: 940.33

(Example 4)

Synthesized in the same manner as in Example 1, the yield was 34%.
¹ H NMR (400MHz, CDCl ₃ , d): 8.26-8.21 (m, 2H), 8.18-8.14 (m, 2H), 7.65-7.56 (m, 10H), 7.34-7.22 (m, 8H), 7.19- 7.10 (m, 4H), 6.80-6.74 (m, 2H), 5.81 (d, J = 8.0 Hz, 2H).
MS (ASAP): 951.36 [M+H] ⁺ calculated value C68H30D10N6: 950.39

(Example 5)

Under a nitrogen atmosphere, 2,5-difluoro-3,6-diphenyl-1,4-benzenedicarbonitrile (0.60 g, 1.9 mmol), 2-phenyl-5H-benzofuro[3,2-c]carbazole ( 1.58 g, 4.7 mmol) and K ₂ CO ₃ (0.79 g, 5.7 mmol) in dimethylformamide (30 mL) was stirred at 130° C. for 22 hours. Then, the temperature was returned to room temperature, and the reaction was terminated with water and methanol. The obtained precipitate was filtered, and the filtrate was purified by column chromatography (toluene/hexane = 2/1) and reprecipitation (toluene/hexane) to give an orange solid (1.07 g, 1.13 mmol, 60% ).
¹ H NMR (400MHz, CDCl ₃ , d): 8.69 (s, 2H), 8.03-8.00 (m, 4H), 7.82-7.75 (m, 8H), 7.57-7.35 (m, 12H), 7.59-7.21 ( m, 6H), 7.11-7.04 (m, 6H).
MS (ASAP): 943.58 [M+H] ⁺ Calcd for. C68H38N4O2: 942.30

(Example 6)

Synthesized in the same manner as in Example 5, the yield was 80%.
¹ H NMR (400MHz, CDCl ₃ , d): 8.67 (s, 2H), 8.02-7.99 (m, 4H), 7.81-7.74 (m, 8H), 7.55-7.34 (m, 12H), 7.26-7.20 ( m, 2H).
MS (ASAP): 953.58 [M+H] ⁺ calculated value C68H28D10N4O2: 952.36

(Example 7)

Synthesized in the same manner as in Example 5, the yield was 82%.
¹ H NMR (400MHz, CDCl ₃ , d): 8.67 (s, 2H), 8.02-7.99 (m, 4H), 7.77-7.74 (m, 4H), 7.51-7.33 (m, 6H), 7.26-7.21 ( m, 2H).
MS (ASAP): 963.63 [M+H] ⁺ .calculated C68H18D20N4O2: 962.43

(Example 8)

Synthesized in the same manner as in Example 5, the yield was 48%.
¹ H NMR (400MHz, CDCl ₃ , d): 8.44 (d, J = 8.0 Hz, 2H), 8.32 (d, J = 8.4 Hz, 2H), 8.26-8.21 (m, 4H), 8.09-7.95 (m , 6H), 7.90-7.86 (m, 4H), 7.77-7.75 (m, 2H), 7.55-7.45 (m, 4H), 7.21-7.12 (m, 4H), 7.02-6.94 (m, 6H).
MS (ASAP): 891.41 [M+H] ⁺ .calculated C64H34N4O2: 890.27

(Example 9)

Synthesized in the same manner as in Example 5, the yield was 71%.
MS (ASAP): 890.2 [M] ⁺ calculated value C64H34N4O2: 890.2

(Example 10)

Synthesized in the same manner as in Example 5, the yield was 45%.
¹ H NMR (400MHz, CDCl ₃ , d): 9.85 (d, J = 8,8 Hz, 2H), 8.36 (dd, J = 8.4, 2.4 Hz, 2H), 8.29 (d, J = 7,2 Hz , 2H), 8.26-8.16 (m, 6H), 8.09-8.02 (m, 4H), 7.93 (t, J = 6,8 Hz, 2H), 7.65 (t, J = 7,2 Hz, 2H), 7.59 (t, J = 6,8 Hz, 2H), 7.52 (t, J = 7,2 Hz, 2H), 7.38 (d, J = 8,4 Hz, 4H), 7.11-7.03 (m, 6H) ,
MS (ASAP): 891.33 [M+H] ⁺ calculated C64H35N4O2: 891.28

The compounds of Examples 1 to 10 were purified by sublimation and then used for thin film formation and device fabrication.

(Preparation and evaluation of thin film)
The compound of Example 1 and mCBP were vapor-deposited from different vapor deposition sources on a quartz substrate by a vacuum vapor deposition method at a degree of vacuum of less than 1×10 ⁻³ Pa, and the concentration of the compound of Example 1 was 20% by weight. A thin film having a thickness of 100 nm was formed as a doped thin film. Further, doped thin films were formed in the same manner using the compounds of Examples 2 to 10 instead of Example 1. Furthermore, instead of Example 1, a compound of Comparative Example 1 having the following structure was used to form a doped thin film in the same manner.
When the obtained thin films were irradiated with excitation light of 300 nm, photoluminescence was observed in all the thin films, so the maximum emission wavelength was measured. Also, the lifetime (τ ₂ ) of delayed fluorescence was obtained from the transient decay curve of luminescence. The results were as shown in Table 8. Table 8 also shows the results of measuring the HOMO energy and LUMO energy of each compound.
From the results in Table 8, it was confirmed that the delayed fluorescence lifetime (τ ₂ ) of each of the compounds of Examples 1 to 10 was significantly shorter than that of the compound of Comparative Example 1.

(Preparation of organic electroluminescence element)
Each thin film is laminated at a degree of vacuum of 1×10 ⁻⁶ Pa by a vacuum evaporation method on a glass substrate on which an anode made of indium tin oxide (ITO) with a thickness of 100 nm is formed. First, HATCN is formed on ITO to a thickness of 10 nm, and NPD is formed thereon to a thickness of 30 nm. Next, TrisPCz is formed thereon to a thickness of 10 nm, and H1 is further formed thereon to a thickness of 5 nm. Next, the compound of Example 1 and H1 are co-deposited from different deposition sources to form a 30 nm thick emitting layer. At this time, the concentration of the compound of Example 1 is 35% by weight. SF3TRZ is formed thereon to a thickness of 10 nm, and SF3TRZ and Liq are co-deposited thereon from different vapor deposition sources to form a thickness of 30 nm. At this time, SF3TRZ:Liq (weight ratio) is 7:3. Further, a cathode is formed by forming Liq to a thickness of 2 nm and then depositing aluminum (Al) to a thickness of 100 nm.
Using the compounds of Examples 2 to 10 in place of the compound of Example 1, organic electroluminescence devices are produced in the same manner.
All of the produced organic electroluminescence devices have a short lifetime (τ2) of delayed fluorescence.

REFERENCE SIGNS LIST 1 substrate 2 anode 3 hole injection layer 4 hole transport layer 5 light emitting layer 6 electron transport layer 7 cathode

Claims

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

[In the general formula (1),
Two to three of R 1 to R 4 each independently represent a donor group, at least one of which is an indol-1-yl group with condensed rings. The ring-fused indol-1-yl group forms a condensed ring having 4 or more rings by ring condensation with indole, and the condensed ring may be substituted.
1 to 2 of R 1 to R 4 each independently represent a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group bonded via a carbon atom.
The remaining R 1 to R 4 represent hydrogen atoms or deuterium atoms. ]
two of R 1 to R 4 are each independently a donor group, at least one of which is an indol-1-yl group to which the ring is condensed;
one of R 1 to R 4 is a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group bonded at a carbon atom;
The compound according to claim 1, wherein the remaining R 1 -R 4 are hydrogen atoms or deuterium atoms.
two of R 1 to R 4 are each independently a donor group, at least one of which is an indol-1-yl group to which the ring is condensed;
2. The compound of claim 1, wherein two of R 1 -R 4 are substituted or unsubstituted aryl groups or substituted or unsubstituted heteroaryl groups attached at a carbon atom.
three of R 1 to R 4 are each independently a donor group, at least one of which is an indol-1-yl group to which the ring is condensed;
2. The compound of claim 1, wherein one of R 1 -R 4 is a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group attached at a carbon atom.
each of R 1 and R 4 is independently a donor group;
A compound according to any one of claims 1 to 4, wherein R 3 is a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group attached at a carbon atom.
R 2 and R 4 are each independently a donor group;
A compound according to any one of claims 1 to 4, wherein R 3 is a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group attached at a carbon atom.
The compound according to any one of claims 1 to 6, wherein the condensed ring has 5 or more rings.
The compound according to claim 7, wherein a carbon atom constituting the skeleton of the condensed ring having 4 or more rings is substituted with a substituted or unsubstituted aryl group.
The compound according to claim 7, wherein the condensed ring skeleton having 4 or more rings contains a nitrogen atom, and the nitrogen atom is substituted with a substituted or unsubstituted aryl group.
The ring condensed to the benzene ring constituting the indol-1-yl group is a substituted or unsubstituted furan ring, a substituted or unsubstituted thiophene ring, or a substituted or unsubstituted pyrrole ring, wherein the furan The compound according to any one of claims 1 to 9, wherein the ring, said thiophene ring and said pyrrole ring may be further condensed with another ring.
The compound according to any one of claims 1 to 10, wherein the indol-1-yl group to which said ring is fused has any of the following fused rings.

[In each structure above, hydrogen atoms may be substituted, and rings may be condensed. ]
The compound according to any one of claims 1 to 10, wherein the ring-fused indol-1-yl group has any of the following condensed ring skeletons.

[In each structure above, hydrogen atoms may be substituted, and rings may be condensed. ]
The compound according to any one of claims 1 to 12, wherein the indol-1-yl group to which the ring is condensed has a structure in which heterocycles are condensed at positions 4 and 5 of the indole ring.
The compound according to any one of claims 1 to 13, wherein Ar is a substituted or unsubstituted phenyl group or a substituted or unsubstituted pyridyl group.
The compound according to any one of claims 1 to 14, consisting of atoms selected from the group consisting of carbon atoms, hydrogen atoms, deuterium atoms, nitrogen atoms, oxygen atoms and sulfur atoms.
A luminescent material comprising the compound according to any one of claims 1 to 15.
A light emitting device comprising the compound according to any one of claims 1 to 15.
The light-emitting device according to claim 17, wherein the light-emitting device has a light-emitting layer, and the light-emitting layer contains the compound and a host material.
The light-emitting device according to claim 18, wherein the light-emitting device has a light-emitting layer, the light-emitting layer contains the compound and a light-emitting material, and emits light mainly from the light-emitting material.