Compound, composition, host material, electron blocking material and organic light-emitting device

Abstract

An organic light emitting element which uses a compound represented by the general formula has high thermal stability and excellent light emission characteristics. Each of R1 to R7 represents a hydrogen atom, a deuterium atom, an alkyl group or an aryl group; and at least one of R1 to R4 represents an aryl group. Each of R8 to R19 represents a hydrogen atom, a deuterium atom or an alkyl group.

Description

[Technical Field]

[0001] The present invention relates to a compound useful as a host material or the like, a composition using the compound, and an organic light-emitting device. [Background technology]

[0002] Active research has been conducted into improving the luminous efficiency of light-emitting elements such as organic electroluminescent elements (organic EL elements). In particular, various efforts have been made to improve the luminous efficiency by newly developing and combining electron transport materials, hole transport materials, luminescent materials, host materials, etc. that constitute organic electroluminescent elements. Among these, organic electroluminescent elements that utilize delayed fluorescent materials have been developed and are attracting attention (see Non-Patent Document 1).

[0003] Delayed fluorescent materials are materials that, in an excited state, undergo reverse intersystem crossing from an excited triplet state to an excited singlet state, and then emit fluorescence upon returning from that excited singlet state to the ground state. Fluorescence via this pathway is observed later than fluorescence from the excited singlet state (normal fluorescence) that arises directly from the ground state, hence the term delayed fluorescence. For example, when a light-emitting compound is excited by carrier injection, the probability of occurrence of the excited singlet state and the excited triplet state is statistically 25%:75%, so there is a limit to the improvement in luminous efficiency when relying solely on fluorescence from the directly arisen excited singlet state. On the other hand, delayed fluorescent materials can utilize not only the excited singlet state but also the excited triplet state for fluorescence emission via the above-mentioned reverse intersystem crossing pathway, thereby achieving higher luminous efficiency than conventional fluorescent materials. Delayed fluorescent materials with these characteristics are generally used together with host materials in the emissive layer of organic electroluminescent devices, where they actually contribute to improving luminous efficiency. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] Uoyama et al, Nature, 492, 234-238 (2012) Summary of the Invention [Problem to be solved by the invention]

[0005] For the host material to be combined with the delayed fluorescent material, a compound having a minimum excited singlet energy greater than that of the delayed fluorescent material is selected. However, even if a host material that has been used in combination with a conventional fluorescent material that does not emit delayed fluorescence is directly combined with a delayed fluorescent material, it is not possible to achieve sufficiently practical light-emitting performance. In particular, organic electroluminescent elements using delayed fluorescent materials have room for improvement in light-emitting performance when driven at high temperatures. For this reason, the present inventors have conducted research to improve the light-emitting performance and thermal stability of organic light-emitting elements using delayed fluorescent materials when driven at high temperatures. [Means for solving the problem]

[0006] As a result of intensive research, the present inventors have found that when a compound having a specific structure is used in combination with a delayed fluorescent material in an organic light-emitting device, high luminous efficiency and low driving voltage can be maintained even under high temperature driving. The present invention has been proposed based on this finding, and specifically has the following configuration.

[0007] [1] A compound represented by the following general formula (1): [ka] [In general formula (1), R 1 ~R 7 each independently represents a hydrogen atom, a deuterium atom, an optionally deuterated alkyl group, or a substituted or unsubstituted aryl group; R 1 ~R 4 At least one of R is a substituted or unsubstituted aryl group. 8 ~R 19 each independently represents a hydrogen atom, a deuterium atom, or an optionally deuterated alkyl group. [2] R 1 ~R 4 The compound according to [1], wherein only one of the groups is a substituted or unsubstituted aryl group. [3] R 2 is a substituted or unsubstituted aryl group. [4] R 4 The compound according to any one of [1] to [3], wherein is a substituted or unsubstituted aryl group. [5] The compound according to any one of [1] to [4], wherein the substituted or unsubstituted aryl group is a substituted or unsubstituted phenyl group. [6] The compound according to any one of [1] to [5], wherein the substituted or unsubstituted aryl group is a substituted or unsubstituted dibenzofuryl group or a substituted or unsubstituted dibenzothienyl group. [7] R 5 ~R 11 The compound according to any one of [1] to [6], wherein each of the is independently a hydrogen atom or a deuterium atom. [8] R 12 ~R 19 The compound according to any one of [1] to [7], wherein each of the is independently a hydrogen atom or a deuterium atom. [9] R 1 ~R 4 The compound according to any one of [1] to [8], wherein at least one of the groups contains a deuterium atom.

[10] R 12 ~R 19 The compound according to any one of [1] to [9], wherein at least one of the groups contains a deuterium atom.

[11] A host material comprising the compound according to any one of [1] to

[10] .

[12] The host material according to

[10] , for use together with a delayed fluorescent material.

[13] The host material according to

[11] , for use together with a compound represented by the following general formula (G): General formula (G) [ka] [In the general formula (G), X 1 and X 2 is a nitrogen atom on one side and a boron atom on the other side. 1 ~R 26 , A 1 , A 2 R each independently represents a hydrogen atom, a deuterium atom, or a substituent. 1 and R 2 , R 2 and R 3 , R 3 and R 4 , R 4 and R 5 , R 5 and R 6 , R 6 and R 7 , R 7 and R 8 , R 8 and R 9 , R 9 and R 10 , R 10 and R 11 , R 11 and R 12 , R 13 and R 14 , R 14 and R 15 , R 15 and R 16 , R 16 and R 17 , R 17 and R 18 , R 18 and R 19 , R 19 and R 20 , R 20 and R 21 , R 21 and R 22 , R 22 and R 23 , R 23 and R 24 , R 24 and R 25 , R 25 and R 26 may be bonded to each other to form a cyclic structure. 1 is a nitrogen atom, R 17 and R 18 are bonded to each other as a single bond to form a pyrrole ring, and X2 is a nitrogen atom, R 21 and R 22 are bonded to each other as a single bond to form a pyrrole ring. In one aspect of the present invention, X 1 is a nitrogen atom, and R 7 and R 8 and R 21 and R 22 are bonded via a nitrogen atom to form a six-membered ring, and R 17 and R 18 When they are bonded to each other to form a single bond, R 1 ~R 6 At least one of R is a substituted or unsubstituted aryl group, or R 1 and R 2 , R 2 and R 3 , R 3 and R 4 , R 4 and R 5 , R 5 and R 6 In one embodiment of the present invention, any of X 1 is a boron atom, and X 2 is a nitrogen atom, and R 7 and R 8 , R 17 and R 18 When they are bonded to each other to form a ring structure containing a boron atom, the ring structure is a 5- to 7-membered ring, and when it is a 6-membered ring, R 7 and R 8 , R 17 and R 18 are bonded to each other to form -B(R 32 )-, -CO-, -CS- or -N(R 27 )- is formed. R 27 represents a hydrogen atom, a deuterium atom or a substituent.

[14] An electron-blocking material comprising the compound according to any one of [1] to

[10] .

[15] The electron-blocking material according to

[14] , for use in combination with a delayed fluorescent material.

[16] The electron-blocking material according to

[14] , for use in combination with the compound represented by the general formula (G).

[17] A composition obtained by doping the compound according to any one of [1] to

[10] with a delayed fluorescent material.

[18] The composition according to

[17] , which is in the form of a film.

[19] The composition according to

[17] or

[18] , wherein the delayed fluorescent material is a compound having a cyanobenzene structure in which one cyano group is substituted on a benzene ring.

[20] The composition according to

[17] or

[18] , wherein the delayed fluorescent material is a compound having a dicyanobenzene structure in which two cyano groups are substituted on a benzene ring.

[21] The composition according to

[17] or

[18] , wherein the delayed fluorescent material is a compound represented by the following general formula (E): General formula (E) [ka] [In general formula (E), R 1 ~R 4 each independently represents a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a donor group. 1 ~R 4 Two or more of X are donor groups, and at least one of the two or more donor groups is a substituted ring-fused carbazol-9-yl group. 1 ~X 3 Each independently represents N or C(R), but X 1 ~X 3 At least one of the groups is N. R represents a hydrogen atom, a deuterium atom, or a substituent. Ar 1 and Ar 2 Each of L independently represents a substituted or unsubstituted aryl group. 1 represents a single bond or a divalent linking group.

[22] The composition according to any one of

[17] to

[21] , further comprising a fluorescent compound having a minimum excited singlet energy lower than those of the host material and the delayed fluorescent material.

[23] The composition according to any one of

[17] to

[22] , wherein the delayed fluorescent material or the fluorescent compound is a compound represented by the general formula (G).

[24] An organic light-emitting device having a layer made of the composition according to any one of

[17] to

[23] .

[25] The organic light-emitting device according to

[24] , wherein the layer is composed only of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms, oxygen atoms, sulfur atoms, boron atoms, and halogen atoms.

[26] The organic light-emitting device according to

[24] , wherein the layer is composed only of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms, oxygen atoms, and sulfur atoms.

[27] The organic light-emitting device according to any one of

[24] to

[26] , which is an organic electroluminescence device.

[28] The organic light-emitting device according to any one of

[24] to

[27] , wherein the composition does not contain the fluorescent compound, and the largest component of the light emitted from the device is light emitted from the delayed fluorescent material.

[29] The organic light-emitting device according to any one of

[24] to

[27] , wherein the composition contains the fluorescent compound, and the largest component of the light emitted from the device is light emitted from the fluorescent compound. [Effects of the Invention]

[0008] By using the compound of the present invention, it is possible to provide an organic light-emitting device that can maintain high luminous efficiency and low driving voltage even under high temperature driving conditions. Furthermore, the organic light-emitting device using the compound of the present invention exhibits excellent luminous properties. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 2 is a schematic cross-sectional view showing an example of a layer structure of an organic electroluminescence element. DETAILED DESCRIPTION OF THE INVENTION

[0010] The present invention will be described in detail below. The following description of the constituent elements may be based on representative embodiments or specific examples of the present invention, but the present invention is not limited to such embodiments or specific examples. In this specification, a numerical range expressed using "to" means a range that includes the numerical values ​​before and after "to" as the lower and upper limits. Furthermore, there are no particular restrictions on the isotope species of hydrogen atoms present in the molecules of the compounds used in the present invention.

[0011] (Compound represented by general formula (1)) In the present invention, a compound represented by the following general formula (1) is used. [ka]

[0012] In general formula (1), R 1 ~R 7 each independently represents a hydrogen atom, a deuterium atom, an optionally deuterated alkyl group, or a substituted or unsubstituted aryl group; R 1 ~R 4 At least one of R is a substituted or unsubstituted aryl group. 8 ~R 19 each independently represents a hydrogen atom, a deuterium atom, or an optionally deuterated alkyl group.

[0013] The "alkyl group" in this application may be linear, branched, or cyclic. It may also be a mixture of two or more of the linear, cyclic, and branched moieties. The number of carbon atoms in the alkyl group may be, for example, 1 or more, 2 or more, or 4 or more. The number of carbon atoms may be 30 or less, 20 or less, 10 or less, 6 or less, or 4 or less. Specific examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, an n-pentyl group, an isopentyl group, an n-hexyl group, a cyclopentyl group, a cyclohexyl group, and a cycloheptyl group. In one embodiment of the present invention, the alkyl group has 1 to 4 carbon atoms. In one embodiment of the present invention, the alkyl group is a methyl group. In one embodiment of the present invention, the alkyl group is an isopropyl group. In one embodiment of the present invention, the alkyl group is a tert-butyl group. When multiple alkyl groups are present in the molecule represented by general formula (1), these alkyl groups may be the same or different. In one embodiment of the present invention, all alkyl groups in the molecule represented by general formula (1) are the same. The number of alkyl groups in the molecule represented by general formula (1) can be 0 or more, 1 or more, 2 or more, 4 or more, or 8 or more. The number of alkyl groups in the molecule represented by general formula (1) may be 20 or less, 10 or less, 5 or less, or 3 or less. The number of alkyl groups in the molecule represented by general formula (1) may be 0. Note that the number of alkyl groups here includes the number of alkyl groups substituted with aryl groups. In this application, an "optionally deuterated alkyl group" means that at least one hydrogen atom of the alkyl group may be substituted with a deuterium atom. All hydrogen atoms of the alkyl group may be substituted with deuterium atoms. For example, optionally deuterated methyl groups include CH, CDH, CDH, and CD. The "optionally deuterated alkyl group" is preferably an alkyl group that is not at all deuterated or an alkyl group in which all hydrogen atoms are substituted with deuterium atoms. In one embodiment of the present invention, the "optionally deuterated alkyl group" is an alkyl group that is not at all deuterated. In one embodiment of the present invention, the "optionally deuterated alkyl group" is an alkyl group in which all hydrogen atoms are substituted with deuterium atoms. In one embodiment of the present invention, the "optionally deuterated alkyl group" is an undeuterated methyl group [-CH], an undeuterated ethyl group [-CHCH], an undeuterated isopropyl group [-CH(CH)], an undeuterated tert-butyl group [-C(CH)], or a methyl group [-CD] in which all hydrogen atoms are deuterated. In one embodiment of the present invention, the "optionally deuterated alkyl group" is a non-deuterated methyl group [-CH3] or a methyl group [-CD3] in which all hydrogen atoms are deuterated. In one embodiment of the present invention, the molecule represented by general formula (1) contains at least one alkyl group in which at least one hydrogen atom is substituted with a deuterium atom.

[0014] R 1 ~R 7The "aryl group" that can be used in the formula (I) may be a monocyclic ring or a fused ring in which two or more rings are fused. When the aryl group is a monocyclic ring, it is a phenyl group. When the fused ring is a fused ring, it is a group in which one or more rings are further fused to a phenyl group. The ring fused to the phenyl group may be any of an aromatic hydrocarbon ring, an aromatic heterocyclic ring, an aliphatic hydrocarbon ring, and an aliphatic heterocyclic ring, or a ring in which these are fused. Preferably, it is an aromatic hydrocarbon ring or an aromatic heterocyclic ring. An example of an aromatic hydrocarbon ring is a benzene ring. The benzene ring may be fused with another benzene ring or may be fused with a heterocyclic ring such as a pyridine ring. The aromatic heterocyclic ring refers to a ring exhibiting aromaticity that contains a heteroatom as a ring skeleton-constituting atom, and is preferably a 5- to 7-membered ring. For example, a 5-membered ring or a 6-membered ring can be used. In one embodiment of the present invention, a furan ring, a thiophene ring, or a pyrrole ring can be used as the aromatic heterocyclic ring, and a furan ring or a thiophene ring can be used preferably. In a preferred embodiment of the present invention, the fused ring is a furan ring of benzofuran, a thiophene ring of benzothiophene, or a pyrrole ring of indole, more preferably a furan ring of benzofuran or a thiophene ring of benzothiophene. When the furan ring of benzofuran is fused, the aryl group becomes a dibenzofuryl group. When the thiophene ring of benzothiophene is fused, the aryl group becomes a dibenzothienyl group. The ring fused to the phenyl group may be a cyclopentadiene ring, a cyclopentene ring, a cyclohexadiene ring, a cyclohexene ring, or the like. When the aryl group is a fused ring, the number of rings constituting the fused ring is preferably 2 to 6, and can be selected from, for example, 2 to 4. Specific examples of rings constituting the aryl group include a benzene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, a triphenylene ring, a dibenzofuran ring, and a dibenzothiophene ring. Specific examples of the aryl group include a phenyl group, a naphthalene-1-yl group, a naphthalene-2-yl group, an anthracen-1-yl group, an anthracen-2-yl group, and an anthracen-9-yl group. Further specific examples of the aryl group include a dibenzofuran-1-yl group, a dibenzofuran-2-yl group, a dibenzofuran-3-yl group, and a dibenzofuran-4-yl group. Furthermore, further specific examples of the aryl group include a dibenzothiophen-1-yl group, a dibenzothiophen-2-yl group, a dibenzothiophen-3-yl group, and a dibenzothiophen-4-yl group. In one embodiment of the present invention, the aryl group is a dibenzofuran-1-yl group or a dibenzothiophen-1-yl group. In one embodiment of the present invention, the aryl group is a dibenzofuran-2-yl group or a dibenzothiophen-2-yl group. In one embodiment of the present invention, the aryl group is a dibenzofuran-3-yl group or a dibenzothiophen-3-yl group. In one embodiment of the present invention, the aryl group is a dibenzofuran-4-yl group or a dibenzothiophen-4-yl group. These specific groups may be substituted.

[0015] The substituent of the aryl group may be selected from the following substituent group A, may be selected from the following substituent group B, may be selected from the following substituent group C, may be selected from the following substituent group D, or may be selected from the following substituent group E. In the present specification, the term "substituent group A" refers to a deuterium atom, a hydroxyl group, a halogen atom (for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom), an alkyl group (for example, having 1 to 40 carbon atoms), an alkoxy group (for example, having 1 to 40 carbon atoms), an alkylthio group (for example, having 1 to 40 carbon atoms), an aryl group (for example, having 6 to 30 carbon atoms), an aryloxy group (for example, having 6 to 30 carbon atoms), an arylthio group (for example, having 6 to 30 carbon atoms), a heteroaryl group (for example, having 5 to 30 ring skeleton atoms), a heteroaryloxy group (for example, having 5 to 30 ring skeleton atoms), a ), heteroarylthio groups (for example, having 5 to 30 atoms constituting the ring skeleton), acyl groups (for example, having 1 to 40 carbon atoms), alkenyl groups (for example, having 1 to 40 carbon atoms), alkynyl groups (for example, having 1 to 40 carbon atoms), alkoxycarbonyl groups (for example, having 1 to 40 carbon atoms), aryloxycarbonyl groups (for example, having 1 to 40 carbon atoms), heteroaryloxycarbonyl groups (for example, having 1 to 40 carbon atoms), silyl groups (for example, trialkylsilyl groups having 1 to 40 carbon atoms), and nitro groups. In this specification, the term "substituent group B" refers to one group or a combination of two or more groups selected from the group consisting of a deuterium atom, an alkyl group (e.g., having 1 to 40 carbon atoms), an alkoxy group (e.g., having 1 to 40 carbon atoms), an aryl group (e.g., having 6 to 30 carbon atoms), an aryloxy group (e.g., having 6 to 30 carbon atoms), a heteroaryl group (e.g., having 5 to 30 ring skeleton atoms), a heteroaryloxy group (e.g., having 5 to 30 ring skeleton atoms), and a diarylaminoamino group (e.g., having 0 to 20 carbon atoms). In this specification, the term "substituent group C" refers to one group or a combination of two or more groups selected from the group consisting of deuterium atoms, alkyl groups (e.g., having 1 to 20 carbon atoms), aryl groups (e.g., having 6 to 22 carbon atoms), heteroaryl groups (e.g., having 5 to 20 ring skeleton atoms), and diarylamino groups (e.g., having 12 to 20 carbon atoms). In this specification, the term "substituent group D" refers to one group or a combination of two or more groups selected from the group consisting of deuterium atoms, alkyl groups (e.g., having 1 to 20 carbon atoms), aryl groups (e.g., having 6 to 22 carbon atoms), and heteroaryl groups (e.g., having 5 to 20 ring skeleton atoms). As used herein, the term "substituent group E" refers to one group or a combination of two or more groups selected from the group consisting of deuterium atoms, alkyl groups (e.g., having 1 to 20 carbon atoms) and aryl groups (e.g., having 6 to 22 carbon atoms).

[0016] In one aspect of the present invention, R 1 ~R 7 The aryl group that R may take is a substituted or unsubstituted phenyl group, a substituted or unsubstituted dibenzofuryl group, or a substituted or unsubstituted dibenzothienyl group. 1 ~R 7 The aryl group that R may take is a phenyl group that may be substituted with one or more groups selected from the group consisting of a deuterium atom, an alkyl group, and an aryl group, for example, a phenyl group that may be substituted with one or more groups selected from the group consisting of a deuterium atom and a phenyl group. 1 ~R 7 The aryl group that R may take is a dibenzofuryl group that may be substituted with one or more groups selected from the group consisting of a deuterium atom, an alkyl group, and an aryl group, for example, a dibenzofuryl group that may be substituted with a deuterium atom. 1 ~R 7 The aryl group that R may take is a dibenzothienyl group that may be substituted with one or more groups selected from the group consisting of a deuterium atom, an alkyl group, and an aryl group, for example, a dibenzothienyl group that may be substituted with a deuterium atom. 1 ~R 4 At least one of the groups contains a deuterium atom. R in general formula (1) 1 ~R 7 The number of substituted or unsubstituted aryl groups among R is 1 to 4, preferably 1 or 2, for example 1. In one embodiment of the present invention, R 1 ~R 4 The number of substituted or unsubstituted aryl groups among R is 1 or 2, for example 1, for example 2. In one embodiment of the present invention, R 5 ~R 7The number of substituted or unsubstituted aryl groups among R is 0 or 1, for example, 0, for example, 1. In one embodiment of the present invention, at least R 1 is a substituted or unsubstituted aryl group. In one embodiment of the present invention, at least R 2 is a substituted or unsubstituted aryl group. In one embodiment of the present invention, at least R 3 is a substituted or unsubstituted aryl group. In one embodiment of the present invention, at least R 4 is a substituted or unsubstituted aryl group. In one embodiment of the present invention, at least R 5 is a substituted or unsubstituted aryl group. In one embodiment of the present invention, at least R 6 is a substituted or unsubstituted aryl group. In one embodiment of the present invention, at least R 7 is a substituted or unsubstituted aryl group. 1 In one aspect of the invention, only R 2 In one aspect of the invention, only R 3 In one aspect of the invention, only R 4 In one aspect of the invention, only R 1 ~R 7 Among these, all are hydrogen atoms or deuterium atoms except for the substituted or unsubstituted aryl group, for example, all are hydrogen atoms.

[0017] In general formula (1), R 1 ~R 7 Specific examples of substituted or unsubstituted aryl groups that can be used by the general formula (1) are listed below. However, the structures that can be used in the present invention should not be construed as being limited by these specific examples. In the following specific examples, * indicates the R 1 ~R 7represents the bonding position to the benzene ring to which the methyl group is bonded. In this application, the methyl group is not represented as CH3 but is omitted. For example, Ar2 to Ar7 are each substituted with a methyl group, Ar8 and Ar9 are substituted with an isopropyl group, and Ar10 and Ar11 are substituted with a tert-butyl group. [ka]

[0018] Ar2(d) to Ar11(d) are examples of alkyl groups of Ar2 to Ar11 in which all hydrogen atoms have been replaced with deuterium atoms. Ar1(D) to Ar21(D) are examples of alkyl groups of Ar1 to Ar21 in which all hydrogen atoms have been replaced with deuterium atoms.

[0019] R in general formula (1) 8 ~R 11 Each independently represents a hydrogen atom, a deuterium atom, or an alkyl group which may be deuterated. For details and specific examples of alkyl groups, see R 1 ~R 7 In one aspect of the present invention, R 8 ~R 11 are each independently a hydrogen atom or a deuterium atom. 8 ~R 11 is a hydrogen atom. In general formula (1), R 8 ~R 11 Specific examples of metaphenylene groups to which are bonded are listed below. However, the structures that can be employed in the present invention are not limited to these specific examples. In the specific examples below, one of the *s represents the position where the group is bonded to the nitrogen atom of carbazole in general formula (1), and the other represents the position where the group is bonded to dibenzofuran. In this application, methyl groups are not represented as CH3 and are omitted. For example, L2 to L6 are each substituted with a methyl group, L7 is substituted with an ethyl group, and L8 is substituted with an isopropyl group. t-Bu represents a tert-butyl group, and D represents a deuterium atom. [ka]

[0020] The alkyl groups L2 to L8 above, in which all hydrogen atoms have been replaced with deuterium atoms, are exemplified here as L2(d) to L8(d), respectively. The alkyl groups L1 to L14 above, in which all hydrogen atoms have been replaced with deuterium atoms, are exemplified here as L1(D) to L14(D), respectively.

[0021] R in general formula (1) 12 ~R 19 Each independently represents a hydrogen atom, a deuterium atom, or an alkyl group which may be deuterated. For details and specific examples of alkyl groups, see R 1 ~R 7 In one aspect of the present invention, R 12 ~R 19 are each independently a hydrogen atom or a deuterium atom. 12 ~R 19 is a hydrogen atom. In general formula (1), R 12 ~R 19 Specific examples of carbazol-9-yl groups to which are bonded are listed below. However, the structures that can be employed in the present invention should not be construed as being limited by these specific examples. In the specific examples below, * indicates the position of bonding to the metaphenylene group in general formula (1). In the present application, methyl groups are omitted and not represented as CH3. For example, Cz2 to Cz5 are each substituted with a methyl group, Cz6 is substituted with an ethyl group, Cz7 is substituted with an isopropyl group, and Cz8 is substituted with a tert-butyl group. [ka]

[0022] The alkyl groups Cz2 to Cz8 above, each having all hydrogen atoms substituted with deuterium atoms, are exemplified here as Cz2(d) to Cz8(d), respectively. The alkyl groups Cz1 to Cz8 above, each having all hydrogen atoms substituted with deuterium atoms, are exemplified here as Cz1(D) to Cz8(D), respectively.

[0023] In one aspect of the present invention, R in general formula (1) 5 ~R 19 are each independently a hydrogen atom or a deuterium atom, for example, all are hydrogen atoms. In one embodiment of the present invention, R other than a substituted or unsubstituted aryl group 1 ~R 4 and R 5 ~R 19 are each independently a hydrogen atom or a deuterium atom, for example, all are hydrogen atoms. 2 is a substituted or unsubstituted aryl group, and R 1 and R 3 ~R 19 are each independently a hydrogen atom or a deuterium atom, for example, all are hydrogen atoms. 4 is a substituted or unsubstituted aryl group, and R 1 ~R 3 and R 5 ~R 19 are each independently a hydrogen atom or a deuterium atom, for example, all are hydrogen atoms. 1 ~R 4 At least one (e.g., one, e.g., R 2 For example, R 4 (only one) is a phenyl group optionally substituted with a deuterium atom, a dibenzofuryl group optionally substituted with a deuterium atom, or a dibenzothienyl group optionally substituted with a deuterium atom, and any other R 1 ~R 4 and R 5 ~R 19 are each independently a hydrogen atom or a deuterium atom, for example, all are hydrogen atoms.

[0024] In one embodiment of the present invention, the compound of general formula (1) is represented by the following general formula (2): 1 , R 3 ~R 19 For the explanation and preferred range of , please refer to the corresponding description of general formula (1). Ar is a substituted or unsubstituted aryl group, please refer to the corresponding description of general formula (1). [ka]

[0025] In one embodiment of the present invention, the compound of general formula (1) is represented by the following general formula (3): 1 ~R 3 , R 5 ~R 19 For the explanation and preferred range of , please refer to the corresponding description of general formula (1). Ar is a substituted or unsubstituted aryl group, please refer to the corresponding description of general formula (1). [ka]

[0026] Specific examples of the compound represented by general formula (1) are listed below, but the compounds that can be used in the present invention are not limited to these specific examples. Below, each compound is specified by specifying Ar in each structure. [ka] JPEG0007788702000011.jpg185170JPEG0007788702000012.jpg176170

[0027] A preferred group of compounds represented by general formula (1) includes the group consisting of the following compounds: [ka] JPEG0007788702000014.jpg61170

[0028] The compound represented by general formula (1) is useful as a host material for doping with a light-emitting material. In particular, it is useful as a host material for doping with a delayed fluorescent material. The doping material may be one or more types. The doping material is selected from those having a lower minimum excited singlet energy than the compound represented by general formula (1). Such a doping material is preferably a delayed fluorescent material described below. The compound represented by general formula (1) is also useful as a carrier blocking material, for example, as an electron blocking material. It can be effectively used in a blocking layer (for example, an electron blocking layer) in an organic light-emitting device such as an organic electroluminescence device. In this case, the compound represented by general formula (1), which is an electron blocking material, is preferably used in combination with a delayed fluorescent material. In particular, it is preferably used in combination with a compound represented by general formula (E) shown below or a compound represented by general formula (G) shown below. Here, "used in combination" means used together in one device, and includes, for example, a case in which a delayed fluorescent material is contained in the light-emitting layer and a compound represented by general formula (1) is contained in the electron blocking layer.

[0029] (Delayed fluorescent material) The compound represented by the general formula (1) is useful as a host material to be used together with a delayed fluorescent material. The term "delayed fluorescent material" as used herein refers to an organic compound that undergoes reverse intersystem crossing from an excited triplet state to an excited singlet state in an excited state, and emits delayed fluorescence when returning from the excited singlet state to the ground state. In the present invention, a delayed fluorescent material is one that emits fluorescence with an emission lifetime of 100 ns (nanoseconds) or longer when its emission lifetime is measured using a fluorescence lifetime measurement system (such as a streak camera system manufactured by Hamamatsu Photonics KK). When a compound represented by general formula (1) is used in combination with a delayed fluorescent material, the delayed fluorescent material receives energy from the compound represented by general formula (1) in an excited singlet state and transitions to an excited singlet state. The delayed fluorescent material may also receive energy from the compound represented by general formula (1) in an excited triplet state and transition to an excited triplet state. The delayed fluorescent material has a difference between the excited singlet energy and the excited triplet energy (ΔE ST ) is small, the delayed fluorescent material in the excited triplet state is likely to undergo reverse intersystem crossing to the delayed fluorescent material in the excited singlet state. The delayed fluorescent material in the excited singlet state generated by these pathways contributes to light emission.

[0030] The delayed fluorescent material has a difference ΔE between the lowest excited singlet energy and the lowest excited triplet energy at 77K. ST is preferably 0.3 eV or less, more preferably 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, even more preferably 0.07 eV or less, even more preferably 0.05 eV or less, even more preferably 0.03 eV or less, and particularly preferably 0.01 eV or less. ΔE ST If the δ is small, reverse intersystem crossing from the excited singlet state to the excited triplet state is easily achieved by absorbing thermal energy, and the material functions as a thermally activated delayed fluorescent material. Thermally activated delayed fluorescent materials absorb heat emitted by a device and relatively easily undergo reverse intersystem crossing from the excited triplet state to the excited singlet state, allowing the excited triplet energy to efficiently contribute to light emission.

[0031] In the present invention, the lowest excited singlet energy (E S1 ) and the lowest excited triplet energy (E T1 ) is a value calculated by the following procedure. ST is E S1 -E T1 This is the value obtained by calculating (1) The lowest excited singlet energy (E S1 ) Thin film or toluene solution (concentration 10 -5 A sample is prepared at a concentration of 1000 mol / L. The fluorescence spectrum of this sample is measured at room temperature (300K). The fluorescence spectrum has the emission on the vertical axis and the wavelength on the horizontal axis. A tangent line is drawn to the rising edge of the short wavelength side of this emission spectrum, and the wavelength value λedge [nm] at the intersection of this tangent line and the horizontal axis is found. This wavelength value is converted to an energy value using the following conversion formula and is called E. S1 Let's say. Conversion formula: E S1 [eV]=1239.85 / λedge In the examples described below, emission spectra were measured using an LED light source (M300L4, manufactured by Thorlabs) as the excitation light source and a detector (PMA-12 multichannel spectrometer C10027-01, manufactured by Hamamatsu Photonics KK). (2) The lowest excited triplet energy (E T1 ) The lowest excited singlet energy (E S1 The same sample used in the measurement of ) is cooled to 77[K] with liquid nitrogen, and the sample for phosphorescence measurement is irradiated with excitation light (300 nm), and the phosphorescence is measured using a detector. The emission from 100 milliseconds after irradiation with excitation light is taken as the phosphorescence spectrum. A tangent line is drawn to the rising edge of the short wavelength side of this phosphorescence spectrum, and the wavelength value λedge[nm] at the intersection of this tangent line and the horizontal axis is found. This wavelength value is converted to an energy value using the following conversion formula, and the value is called E T1 Let's say. Conversion formula: E T1 [eV]=1239.85 / λedge The tangent to the rising edge of the phosphorescence spectrum on the short wavelength side is drawn as follows: When moving along the spectral curve from the short wavelength side of the phosphorescence spectrum to the shortest maximum of the spectral maxima, consider the tangent at each point on the curve toward the long wavelength side. The slope of this tangent increases as the curve rises (i.e., as the vertical axis increases). The tangent drawn at the point where this slope is at its maximum is considered to be the tangent to the rising edge of the phosphorescence spectrum on the short wavelength side. Note that a maximum point having a peak intensity that is 10% or less of the maximum peak intensity of the spectrum is not included in the above-mentioned maximum value on the shortest wavelength side, and the tangent drawn at the point where the slope value is the maximum value that is closest to the maximum value on the shortest wavelength side is defined as the tangent to the rising edge on the short wavelength side of the phosphorescence spectrum.

[0032] In a preferred embodiment of the present invention, a compound (cyanobenzene derivative) having a cyanobenzene structure in which one cyano group is substituted on a benzene ring is used as the delayed fluorescent material. In another preferred embodiment of the present invention, a compound (dicyanobenzene derivative) having a dicyanobenzene structure in which two cyano groups are substituted on a benzene ring is used as the delayed fluorescent material. In another preferred embodiment of the present invention, a compound (azabenzene derivative) having an azabenzene structure in which at least one of the carbon atoms constituting the ring skeleton of the benzene ring is substituted with a nitrogen atom is used as the delayed fluorescent material.

[0033] In a preferred embodiment of the present invention, a compound represented by the following general formula (4) is used as the delayed fluorescent material. [ka] In general formula (4), R 21 ~R 23 one of the groups represents a cyano group or a group represented by the following general formula (5), and R 21 ~R 23 The remaining two and R 24 and R 25 At least one of R represents a group represented by the following general formula (6): 21 ~R 25 The remainder represents a hydrogen atom or a substituent (however, the substituent here does not represent a cyano group, a group represented by the following general formula (5), or a group represented by the following general formula (6)). [ka] In general formula (5), L 1 represents a single bond or a divalent linking group, and R 31 and R 32each independently represents a hydrogen atom or a substituent, and * represents the bonding position. [ka] In general formula (6), L 2 represents a single bond or a divalent linking group, and R 33 and R 34 each independently represents a hydrogen atom or a substituent, and * represents the bonding position.

[0034] In a preferred embodiment of the present invention, R 22 is a cyano group. In a preferred embodiment of the present invention, R 22 is a group represented by general formula (5). In one embodiment of the present invention, R 21 is a cyano group or a group represented by general formula (5). 23 is a cyano group or a group represented by general formula (5). 21 ~R 23 In one embodiment of the present invention, one of R 21 ~R 23 One of these is a group represented by general formula (5).

[0035] In a preferred embodiment of the present invention, L in general formula (5) 1 is a single bond. In one aspect of the present invention, L 1 is a divalent linking group, preferably a substituted or unsubstituted arylene group or a substituted or unsubstituted heteroarylene group, more preferably a substituted or unsubstituted arylene group, and even more preferably a substituted or unsubstituted 1,4-phenylene group (with, for example, an alkyl group having 1 to 3 carbon atoms as the substituent). In one embodiment of the present invention, R in general formula (5) 31 and R 32are each independently one group or a combination of two or more groups selected from the group consisting of alkyl groups (e.g., having 1 to 40 carbon atoms), aryl groups (e.g., having 6 to 30 carbon atoms), heteroaryl groups (e.g., having 5 to 30 ring skeleton atoms), alkenyl groups (e.g., having 1 to 40 carbon atoms), and alkynyl groups (e.g., having 1 to 40 carbon atoms) (hereinafter, these groups are referred to as "groups of substituent group A"). In a preferred embodiment of the present invention, R 31 and R 32 are each independently a substituted or unsubstituted aryl group (e.g., having 6 to 30 carbon atoms), and examples of the substituent of the aryl group include the groups in Substituent Group A. In a preferred embodiment of the present invention, R 31 and R 32 are identical.

[0036] In a preferred embodiment of the present invention, L in general formula (6) 2 is a single bond. In one aspect of the present invention, L 2 is a divalent linking group, preferably a substituted or unsubstituted arylene group or a substituted or unsubstituted heteroarylene group, more preferably a substituted or unsubstituted arylene group, and even more preferably a substituted or unsubstituted 1,4-phenylene group (with, for example, an alkyl group having 1 to 3 carbon atoms as the substituent). In one embodiment of the present invention, R in general formula (6) 33 and R 34each independently represents a substituted or unsubstituted alkyl group (e.g., having 1 to 40 carbon atoms), a substituted or unsubstituted alkenyl group (e.g., having 1 to 40 carbon atoms), a substituted or unsubstituted aryl group (e.g., having 6 to 30 carbon atoms), or a substituted or unsubstituted heteroaryl group (e.g., having 5 to 30 carbon atoms). Examples of the substituents on the alkyl group, alkenyl group, aryl group, and heteroaryl group include a hydroxyl group, a halogen atom (e.g., a fluorine atom, a chlorine atom, a bromine atom, an iodine atom), an alkyl group (e.g., having 1 to 40 carbon atoms), an alkoxy group (e.g., having 1 to 40 carbon atoms), an alkylthio group (e.g., having 1 to 40 carbon atoms), an aryl group (e.g., having 6 to 30 carbon atoms), an aryloxy group (e.g., having 6 to 30 carbon atoms), an arylthio group (e.g., having 6 to 30 carbon atoms), a heteroaryl group (e.g., having 5 to 30 ring skeleton atoms), a heteroaryloxy group (e.g., having 5 to 30 ring skeleton atoms), and a heteroarylthi group. Examples thereof include one group or a combination of two or more groups selected from the group consisting of an aryl group (e.g., having 5 to 30 ring skeleton atoms), an acyl group (e.g., having 1 to 40 carbon atoms), an alkenyl group (e.g., having 1 to 40 carbon atoms), an alkynyl group (e.g., having 1 to 40 carbon atoms), an alkoxycarbonyl group (e.g., having 1 to 40 carbon atoms), an aryloxycarbonyl group (e.g., having 1 to 40 carbon atoms), a heteroaryloxycarbonyl group (e.g., having 1 to 40 carbon atoms), a silyl group (e.g., a trialkylsilyl group having 1 to 40 carbon atoms), a nitro group, and a cyano group (hereinafter, these groups are referred to as "groups of substituent group B"). R 33 and R 34 may be bonded to each other via a single bond or a linking group to form a cyclic structure. 33 and R 34 When R is an aryl group, they are preferably bonded to each other via a single bond or a linking group to form a cyclic structure. The linking group here includes -O-, -S-, -N(R 35 )-, -C(R 36 )(R 37 )-, -C(=O)-, -O-, -S-, -N(R 35 )-, -C(R 36 )(R 37 )- is preferred, and -O-, -S-, -N(R 35)- is more preferred. R 35 ~R 37 each independently represents a hydrogen atom or a substituent. The substituent may be selected from the groups in the above-mentioned Substituent Group A or the groups in the below-mentioned Substituent Group B, and is preferably one group or a combination of two or more groups selected from the group consisting of alkyl groups having 1 to 10 carbon atoms and aryl groups having 6 to 14 carbon atoms.

[0037] The group represented by general formula (6) is preferably a group represented by the following general formula (7). [ka]

[0038] L in general formula (7) 11 represents a single bond or a divalent linking group. 11 For a description and preferred range of 2 Reference can be made to the description and preferred ranges of R in general formula (7) 41 ~R 48 R each independently represents a hydrogen atom or a substituent. 41 and R 42 , R 42 and R 43 , R 43 and R 44 , R 44 and R 45 , R 45 and R 46 , R 46 and R 47 , R 47 and R 48may be bonded to each other to form a cyclic structure. The cyclic structure formed by bonding to each other may be an aromatic ring or an aliphatic ring, may contain a heteroatom, and may further be a fused ring of two or more rings. The heteroatom referred to here is preferably selected from the group consisting of a nitrogen atom, an oxygen atom, and a sulfur atom. Examples of the cyclic structure formed include a benzene ring, a naphthalene ring, a pyridine ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring, a pyrrole ring, an imidazole ring, a pyrazole ring, an imidazoline ring, an oxazole ring, an isoxazole ring, a thiazole ring, an isothiazole ring, a cyclohexadiene ring, a cyclohexene ring, a cyclopentaene ring, a cycloheptatriene ring, a cycloheptadiene ring, a cycloheptaene ring, a furan ring, a thiophene ring, a naphthyridine ring, a quinoxaline ring, and a quinoline ring. For example, a ring formed by condensing multiple rings, such as a phenanthrene ring or a triphenylene ring, may also be formed. The number of rings contained in the group represented by general formula (7) may be selected from the range of 3 to 5, or may be selected from the range of 5 to 7. R 41 ~R 48 Examples of the substituent that R may have include the groups in the above-mentioned substituent group B, and preferably an unsubstituted alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 10 carbon atoms which may be substituted with an unsubstituted alkyl group having 1 to 10 carbon atoms. In a preferred embodiment of the present invention, R 41 ~R 48 is a hydrogen atom or an unsubstituted alkyl group having 1 to 10 carbon atoms. In a preferred embodiment of the present invention, R 41 ~R 48 is a hydrogen atom or an unsubstituted aryl group having 6 to 10 carbon atoms. In a preferred embodiment of the present invention, R 41 ~R 48 are all hydrogen atoms. In the general formula (7), * represents a bonding position.

[0039] In a preferred embodiment of the present invention, an azabenzene derivative is used as the delayed fluorescent material. In a preferred embodiment of the present invention, the azabenzene derivative has an azabenzene structure in which three of the carbon atoms constituting the ring skeleton of the benzene ring are substituted with nitrogen atoms. For example, an azabenzene derivative having a 1,3,5-triazine structure can be preferably selected. In a preferred embodiment of the present invention, the azabenzene derivative has an azabenzene structure in which two of the carbon atoms constituting the ring skeleton of the benzene ring are substituted with nitrogen atoms. For example, azabenzene derivatives having a pyridazine structure, pyrimidine structure, or pyrazine structure can be mentioned, and an azabenzene derivative having a pyrimidine structure can be preferably selected. In one embodiment of the present invention, the azabenzene derivative has a pyridine structure in which one of the carbon atoms constituting the ring skeleton of the benzene ring is substituted with a nitrogen atom.

[0040] In a preferred embodiment of the present invention, a compound represented by the following general formula (8) is used as the delayed fluorescent material. [ka] In the general formula (8), Y 1 , Y 2 and Y 3 At least one of Y represents a nitrogen atom and the rest represent methine groups. 1 is a nitrogen atom, and Y 2 and Y 3 is a methine group. Preferably, Y 1 and Y 2 is a nitrogen atom, and Y 3 is a methine group. More preferably, Y 1 ~Y 3 All of the atoms are nitrogen atoms. In general formula (8), Z 1 ~Z 3 Each of Z independently represents a hydrogen atom or a substituent, and at least one of them is a donor substituent. A donor substituent refers to a group having a negative Hammett σp value. Preferably, Z 1 ~Z 3At least one of Z is a group containing a diarylamino structure (two aryl groups bonded to a nitrogen atom may be bonded to each other), more preferably a group represented by the above general formula (6), for example a group represented by the above general formula (7). 1 ~Z 3 In one embodiment of the present invention, only one of Z is a group represented by general formula (6) or (7). 1 ~Z 3 In one embodiment of the present invention, only two of Z are independently a group represented by general formula (6) or (7). 1 ~Z 3 All of the groups are independently represented by general formula (6) or (7). For details and preferred ranges of general formula (6) and general formula (7), please refer to the corresponding descriptions above. The remaining Z that are not groups represented by general formula (6) or general formula (7) 1 ~Z 3 is preferably a substituted or unsubstituted aryl group (e.g., having 6 to 40 carbon atoms, preferably 6 to 20 carbon atoms), and examples of the substituent of the aryl group herein include one group selected from the group consisting of aryl groups (e.g., having 6 to 20 carbon atoms, preferably 6 to 14 carbon atoms) and alkyl groups (e.g., having 1 to 20 carbon atoms, preferably 1 to 6 carbon atoms), or a group consisting of a combination of two or more groups. In one embodiment of the present invention, general formula (8) does not contain a cyano group.

[0041] In a preferred embodiment of the present invention, a compound represented by the following general formula (9) is used as the delayed fluorescent material. [ka] In the general formula (9), Ar 1 is the following A 1 and D 1 and represents a benzene ring, a naphthalene ring, an anthracene ring, or a phenanthrene ring. 2 , Ar 3may each form a cyclic structure, and when a cyclic structure is formed, it represents a benzene ring, a naphthalene ring, a pyridine ring, or a benzene ring substituted with a cyano group. m1 represents an integer of 0 to 2, and m2 represents an integer of 0 to 1. A 1 represents a cyano group, a phenyl group, a pyrimidyl group, a triazyl group, or a benzonitrile group. D 1 represents a substituted or unsubstituted 5H-indolo[3,2,1-de]phenazin-5-yl group or a substituted or unsubstituted heterocyclic fused carbazolyl group not containing a naphthalene structure, and there are multiple D 1 When present, they may be the same or different. 1 The substituents may be bonded to each other to form a ring structure.

[0042] Preferred compounds that can be used as delayed fluorescent materials are listed below, but the delayed fluorescent materials that can be used in the present invention are not limited to these specific examples. [ka] JPEG0007788702000022.jpg212170JPEG0007788702000023.jpg232170JPEG0007788702000024.jpg212170 JPEG0007788702000025.jpg221170JPEG0007788702000026.jpg216170JPEG0007788702000027.jpg139170

[0043] In a preferred embodiment of the present invention, a compound represented by the following general formula (E) is used as the delayed fluorescent material: General formula (E) includes the above-mentioned TADF3 and TADF72. General formula (E) [ka]

[0044] In general formula (E), R 1 ~R4 each independently represents a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a donor group. 1 ~R 4 Two or more of X are donor groups, and at least one of the two or more donor groups is a substituted ring-fused carbazol-9-yl group. 1 ~X 3 Each independently represents N or C(R), but X 1 ~X 3 At least one of the groups is N. R represents a hydrogen atom, a deuterium atom, or a substituent. Ar 1 and Ar 2 Each of L independently represents a substituted or unsubstituted aryl group. 1 represents a single bond or a divalent linking group.

[0045] In one aspect of the present invention, R 1 ~R 4 In a preferred embodiment of the present invention, at least one of R 1 ~R 4 In a preferred embodiment of the present invention, only one of R 1 is a hydrogen atom or a deuterium atom. 2 is a hydrogen atom or a deuterium atom. 3 is a hydrogen atom or a deuterium atom. 4 is a hydrogen atom or a deuterium atom. In a preferred embodiment of the present invention, R 1 In one embodiment of the present invention, only R 2 In one embodiment of the present invention, only R 3 In one embodiment of the present invention, only R 4 are hydrogen or deuterium atoms. In one aspect of the present invention, R 1 is a substituted or unsubstituted alkyl group. 2 is a substituted or unsubstituted alkyl group.3 is a substituted or unsubstituted alkyl group. 4 is a substituted or unsubstituted alkyl group. In one aspect of the present invention, R 1 is a substituted or unsubstituted aryl group. 2 is a substituted or unsubstituted aryl group. In a preferred embodiment of the present invention, R 3 is a substituted or unsubstituted aryl group. 4 is a substituted or unsubstituted aryl group.

[0046] In a preferred embodiment of the present invention, R 1 ~R 4 Two of R are donor groups, one is a hydrogen atom or a deuterium atom, and one is a substituted or unsubstituted aryl group. 1 ~R 4 Two of R are substituted ring-fused carbazol-9-yl groups, one is a hydrogen atom or a deuterium atom, and one is an unsubstituted aryl group. 1 ~R 4 Two of the groups are ring-fused carbazol-9-yl groups substituted with alkyl or aryl groups, one is a hydrogen atom or a deuterium atom, and the other is an unsubstituted phenyl group. In one aspect of the present invention, R 1 ~R 4 In one embodiment of the present invention, three of R are donor groups and one is a hydrogen atom or a deuterium atom. 1 ~R 4 Three of the R are donor groups, and one is a substituted or unsubstituted aryl group (preferably an unsubstituted aryl group). 1 ~R 4 In one embodiment of the present invention, R is a ring-fused carbazol-9-yl group substituted with an alkyl or aryl group, and one is a hydrogen atom or a deuterium atom. 1 ~R 4Three of the groups are ring-fused carbazol-9-yl groups substituted with an alkyl group or an aryl group, and one is a substituted or unsubstituted aryl group (preferably an unsubstituted aryl group). In one aspect of the present invention, R 1 ~R 4 In one embodiment of the present invention, all of R 1 ~R 4 All of the above are ring-fused carbazol-9-yl groups substituted with alkyl or aryl groups.

[0047] In one aspect of the present invention, R 1 and R 2 is a donor group. In one embodiment of the present invention, R 1 and R 3 is a donor group. In one embodiment of the present invention, R 1 and R 4 is a donor group. In one embodiment of the present invention, R 2 and R 3 is a donor group. In one embodiment of the present invention, R 3 and R 4 is a donor group. In one embodiment of the present invention, R 1 and R 2 and R 3 is a donor group. In one embodiment of the present invention, R 1 and R 2 and R 4 is a donor group. In one embodiment of the present invention, R 1 and R 3 and R 4 is a donor group. In one embodiment of the present invention, R 2 and R 3 and R 4 is a donor group. In a preferred embodiment of the present invention, R 1 is a hydrogen atom or a deuterium atom, and R 2 and R 4 is a donor group (preferably a ring-fused carbazol-9-yl group substituted with an alkyl or aryl group), and R 3 is a substituted or unsubstituted aryl group (preferably an unsubstituted aryl group). In one embodiment of the present invention, R 1is a hydrogen atom or a deuterium atom, and R 2 and R 4 is a donor group (preferably a ring-fused carbazol-9-yl group substituted with an alkyl or aryl group), and R 3 is a substituted or unsubstituted alkyl group (preferably an unsubstituted alkyl group). In one embodiment of the present invention, R 1 is a hydrogen atom or a deuterium atom, and R 2 and R 4 is a donor group (preferably a ring-fused carbazol-9-yl group substituted with an alkyl or aryl group), and R 3 is a hydrogen atom or a deuterium atom. 1 is a substituted or unsubstituted aryl group (preferably an unsubstituted aryl group), and R 2 and R 4 is a donor group (preferably a ring-fused carbazol-9-yl group substituted with an alkyl or aryl group), and R 3 is a hydrogen atom or a deuterium atom. In one aspect of the present invention, R 1 is a hydrogen atom or a deuterium atom, and R 2 ~R 4 is a donor group. In one embodiment of the present invention, R 1 is a hydrogen atom or a deuterium atom, and R 2 ~R 4 is a ring-fused carbazol-9-yl group substituted with an alkyl or aryl group. 1 is a hydrogen atom or a deuterium atom, and R 2 and R 4 is a ring-fused carbazol-9-yl group substituted with an alkyl or aryl group, and R 3 are other donor groups. In a preferred embodiment of the present invention, R 1 and R 2 , R 2 and R 3 , R 3 and R 4 are not bonded to each other to form a ring structure.

[0048] In a preferred embodiment of the present invention, the compound represented by general formula (E) is selected from the following group of compounds: The compound may be selected from Group 1, Group 2, Group 3, Group 4, Group 5, Group 6, Group 7, Group 8, Group 9, Group 10, Group 11, Group 12, or Group 13. [ka] JPEG0007788702000030.jpg252170JPEG0007788702000031.jpg255153JPEG0007788702000032.jpg252170JPEG0007788702000033.jpg255169JPEG0007788702000034.jpg255151JPEG0007788702000035.jpg240170JPEG0007788702000036.jpg139170JPEG0007788702000037.jpg188170JPEG0007788702000038.jpg218170JPEG0007788702000039.jpg255162JPEG0007788702000040.jpg255161JPEG0007788702000041.jpg253170JPEG0007788702000042.jpg255162JPEG0007788702000043.jpg135170JPEG0007788702000044.jpg118170JPEG0007788702000045.jpg255162JPEG0007788702000046.jpg255168JPEG0007788702000047.jpg255155JPEG0007788702000048.jpg123170JPEG0007788702000049.jpg125170JPEG0007788702000050.jpg250170JPEG0007788702000051.jpg244170JPEG0007788702000052.jpg254170JPEG0007788702000053.jpg230170JPEG0007788702000054.jpg255166JPEG0007788702000055.jpg251170JPEG0007788702000056.jpg239170JPEG0007788702000057.jpg241170JPEG0007788702000058.jpg255164JPEG0007788702000059.jpg255168JPEG0007788702000060.jpg248170JPEG0007788702000061.jpg109170

[0049] In the present invention, other known delayed fluorescent materials can be used in appropriate combination with the compound represented by general formula (1), and unknown delayed fluorescent materials can also be used. As delayed fluorescent materials, paragraphs 0008 to 0048 and 0095 to 0133 of WO2013 / 154064, paragraphs 0007 to 0047 and 0073 to 0085 of WO2013 / 011954, paragraphs 0007 to 0033 and 0059 to 0066 of WO2013 / 011955, paragraphs 0008 to 007 of WO2013 / 081088 1 and 0118 to 0133, paragraphs 0009 to 0046 and 0093 to 0134 of JP 2013-256490 A, paragraphs 0008 to 0020 and 0038 to 0040 of JP 2013-116975 A, paragraphs 0007 to 0032 and 0079 to 0084 of WO2013 / 133359 A, paragraphs 0008 to 0032 of WO2013 / 161437 A 0054 and 0101 to 0121, paragraphs 0007 to 0041 and 0060 to 0069 of JP 2014-9352 A, paragraphs 0008 to 0048 and 0067 to 0076 of JP 2014-9224 A, paragraphs 0013 to 0025 of JP 2017-119663 A, paragraphs 0013 to 0026 of JP 2017-119664 A, Examples include compounds encompassed by the general formulas described in paragraphs 0012 to 0025 of JP 222623 A, paragraphs 0010 to 0050 of JP 2017-226838 A, paragraphs 0012 to 0043 of JP 2018-100411 A, and paragraphs 0016 to 0044 of WO 2018 / 047853 A, particularly exemplary compounds that emit delayed fluorescence.Also, Japanese Patent Application Laid-Open No. 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 / 00858 0 publication, WO2014 / 203840 publication, WO2015 / 002213 publication, WO2015 / 016200 publication, WO2015 / 019725 publication, WO2015 / 072470, WO2015 / 108049, WO2015 / 080182, WO2015 / 072537, WO2015 / 080183, JP2015-129240A, WO2015 / 129714, WO2015 / 129715, WO2015 / 133 It is also possible to employ luminescent materials that emit delayed fluorescence, such as those described in WO2015 / 136880, WO2015 / 137244, WO2015 / 137202, WO2015 / 137136, WO2015 / 146541, and WO2015 / 159541. The above publications described in this paragraph are incorporated herein by reference.

[0050] The delayed fluorescent material used in the present invention preferably does not contain metal atoms.For example, as the delayed fluorescent material, a compound consisting of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms, oxygen atoms and sulfur atoms can be selected.For example, as the delayed fluorescent material, a compound consisting of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms and oxygen atoms can be selected.For example, as the delayed fluorescent material, a compound consisting of carbon atoms, hydrogen atoms and nitrogen atoms can be selected.

[0051] In this specification, alkyl groups, alkenyl groups, aryl groups, heteroaryl groups, etc. represent the following groups unless otherwise specified. The "alkyl group" may be linear, branched, or cyclic. It may also contain two or more of the linear, cyclic, and branched groups. The number of carbon atoms in the alkyl group may be, for example, 1 or more, 2 or more, or 4 or more. The number of carbon atoms may be 30 or less, 20 or less, 10 or less, 6 or less, or 4 or less. Specific examples of the alkyl group include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, n-hexyl, isohexyl, 2-ethylhexyl, n-heptyl, isoheptyl, n-octyl, isooctyl, n-nonyl, isononyl, n-decanyl, isodecanyl, cyclopentyl, cyclohexyl, and cycloheptyl. The alkyl group may be further substituted with an aryl group. For the alkyl moieties of "alkoxy groups," "alkylthio groups," "acyl groups," and "alkoxycarbonyl groups," the explanation of "alkyl groups" herein can be referred to. The "alkenyl group" may be linear, branched, or cyclic. It may also contain two or more of the linear, cyclic, and branched moieties. The alkenyl group may have, for example, two or more carbon atoms, or four or more carbon atoms. It may also have 30 or less, 20 or less, 10 or less, 6 or less, or 4 or less carbon atoms. Specific examples of the alkenyl group include ethenyl, n-propenyl, isopropenyl, n-butenyl, isobutenyl, n-pentenyl, isopentenyl, n-hexenyl, isohexenyl, and 2-ethylhexenyl. The substituted alkenyl group may be further substituted with a substituent. The "aryl group" and "heteroaryl group" may be a single ring or a fused ring in which two or more rings are fused. In the case of a fused ring, the number of fused rings is preferably 2 to 6, and can be selected from, for example, 2 to 4. Specific examples of the ring include a benzene ring, a pyridine ring, a pyrimidine ring, a triazine ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, a triphenylene ring, a quinoline ring, a pyrazine ring, a quinoxaline ring, and a naphthyridine ring. Specific examples of the aryl group or heteroaryl group include a phenyl group, a 1-naphthyl group, a 2-naphthyl group, a 1-anthracenyl group, a 2-anthracenyl group, a 9-anthracenyl group, a 2-pyridyl group, a 3-pyridyl group, and a 4-pyridyl group. The terms "arylene group" and "heteroaryl group" can be used in the same manner as in the description of the aryl group and heteroaryl group, except that the valence is changed from 1 to 2. The aryl moiety of an "aryloxy group," an "arylthio group," and an "aryloxycarbonyl group" can also be referred to the explanation of the "aryl group" herein. The heteroaryl moiety of a "heteroaryloxy group," an "heteroarylthio group," and an "heteroaryloxycarbonyl group" can also be referred to the explanation of the "heteroaryl group" herein.

[0052] (composition) The composition of the present invention contains a compound represented by general formula (1) and a delayed fluorescent material. In one embodiment of the present invention, the composition is composed solely of one or more compounds represented by general formula (1) and one or more delayed fluorescent materials. In one embodiment of the present invention, the composition is composed solely of one compound represented by general formula (1) and one delayed fluorescent material. In one embodiment of the present invention, the composition contains a third component in addition to the compound represented by general formula (1) and the delayed fluorescent material. The third component here is neither a compound represented by general formula (1) nor a delayed fluorescent material. The third component may contain only one type, or may contain two or more types. The content of the third component in the composition may be selected from a range of 30% by weight or less, 10% by weight or less, 1% by weight or less, or 0.1% by weight or less. In one embodiment of the present invention, the third component does not emit light. In one embodiment of the present invention, the third component emits fluorescence. In a preferred embodiment of the present invention, the maximum component of light emitted from the composition of the present invention is fluorescence (including delayed fluorescence). In the composition of the present invention, the compound represented by general formula (1) is contained in a larger amount by weight than the delayed fluorescent material. The content of the compound represented by general formula (1) may be selected within a range of 3 times or more by weight, 10 times or more by weight, 100 times or more by weight, 1000 times or more by weight, or, for example, 10,000 times or less by weight of the delayed fluorescent material. In the composition of the present invention, it is preferable to select a delayed fluorescent material having a lower excited singlet energy than the excited singlet energy of the compound represented by general formula (1). The difference in excited singlet energy may be 0.1 eV or more, 0.3 eV or more, or 0.5 eV or more, or 2 eV or less, 1.5 eV or less, or 1.0 eV or less. The composition of the present invention preferably does not contain metal elements. In one embodiment of the present invention, the composition of the present invention consists only of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms, oxygen atoms, sulfur atoms, boron atoms, and halogen atoms. In one embodiment of the present invention, the composition of the present invention consists only of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms, oxygen atoms, and sulfur atoms.

[0053] In one embodiment of the present invention, the compound represented by formula (1) is useful as a host material for use together with a delayed fluorescent material and a fluorescent compound. Therefore, in one embodiment of the present invention, the composition of the present invention includes a fluorescent compound in addition to the compound represented by formula (1) and the delayed fluorescent material.

[0054] The fluorescent compound has a lowest excited singlet energy (E S1 ) is preferably small. The fluorescent compound receives energy from the compound represented by general formula (1) and the delayed fluorescent material in the excited singlet state, and from the delayed fluorescent material that has undergone reverse intersystem crossing from the excited triplet state to the excited singlet state, transitions to the singlet excited state, and then emits fluorescence when returning to the ground state. The fluorescent compound is not particularly limited as long as it can receive energy from the compound represented by general formula (1) and the delayed fluorescent material and emit fluorescence, and the emission may be either fluorescence or delayed fluorescence. In particular, it is preferable that the light emitter used as the fluorescent compound emits fluorescence when returning from the lowest excited singlet energy level to the ground energy level. Two or more fluorescent compounds may be used. For example, by using two or more fluorescent compounds with different emission colors in combination, it is possible to emit light of a desired color. Examples of fluorescent compounds that can be used 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 compounds having a boron-containing polycyclic aromatic skeleton such as diazaboranaphthoanthracene, and other compounds that exhibit a multiple resonance effect. These exemplary skeletons may or may not have a substituent. These exemplary skeletons may also be combined with each other.

[0055] Specific examples of fluorescent compounds include the compounds listed as specific examples of delayed fluorescent materials. In this case, the composition of the present invention contains two or more delayed fluorescent materials, with the one with a higher lowest excited singlet energy functioning as an assist dopant and the one with a lower lowest excited singlet energy functioning as the primary emitting fluorescent compound. The compound used as the fluorescent compound preferably exhibits a PL emission quantum yield of 60% or more, more preferably 80% or more. Furthermore, the compound used as the fluorescent compound preferably exhibits an instantaneous fluorescence lifetime of 50 ns or less, more preferably 20 ns or less. The instantaneous fluorescence lifetime here refers to the emission lifetime of the component that decays most rapidly among multiple exponential decay components observed when measuring the emission lifetime of a compound exhibiting thermally activated delayed fluorescence. Furthermore, the compound used as the third compound preferably has a fluorescence emission rate from the lowest excited singlet (S1) to the ground state that is faster than the intersystem crossing rate from S1 to the lowest excited triplet (T1). For a method for calculating the rate constant of a compound, reference can be made to known literature on thermally activated delayed fluorescent materials (H. Uoyama, et al., Nature 492, 234 (2012), K. Masui, et al., Org. Electron. 14, 2721, (2013), etc.).

[0056] Preferred compounds that can be used as the fluorescent compound together with the delayed fluorescent material are listed below, but the fluorescent compounds that can be used in the present invention should not be construed as being limited to these specific examples.

[0057] [ka] JPEG0007788702000063.jpg215170JPEG0007788702000064.jpg149170

[0058] Furthermore, the compounds described in paragraphs 0220 to 0239 of WO2015 / 022974 can also be particularly preferably used as the fluorescent compound of the present invention.

[0059] In a preferred embodiment of the present invention, a compound represented by the following general formula (G) is used in the light-emitting layer. The compound represented by general formula (G) is preferably employed as a fluorescent compound used in combination with a delayed fluorescent material (assist dopant). The fluorescent compound referred to here is a concept that includes both fluorescent-emitting compounds that emit delayed fluorescence and fluorescent-emitting compounds that do not emit delayed fluorescence, but is preferably a fluorescent-emitting compound that emits delayed fluorescence. The compound represented by general formula (G) may be employed as an assist dopant. General formula (G) [ka]

[0060] In general formula (G), X 1 and X 2 In one embodiment of the present invention, X is a nitrogen atom and the other is a boron atom. 1 is a nitrogen atom, and X 2 is a boron atom. In this case, R 17 and R 18 are bonded to each other as a single bond to form a pyrrole ring. 1 is a boron atom, and X 2 is a nitrogen atom. In this case, R 21 and R 22 are bonded to each other to form a single bond to form a pyrrole ring.

[0061] In general formula (G), R 1 ~R 26 , A 1 , A 2 each independently represents a hydrogen atom, a deuterium atom, or a substituent. R 1 and R 2 , R 2 and R 3 , R 3 and R 4 , R 4 and R 5 , R 5 and R 6 , R 6and R 7 , R 7 and R 8 , R 8 and R 9 , R 9 and R 10 , R 10 and R 11 , R 11 and R 12 , R 13 and R 14 , R 14 and R 15 , R 15 and R 16 , R 16 and R 17 , R 17 and R 18 , R 18 and R 19 , R 19 and R 20 , R 20 and R 21 , R 21 and R 22 , R 22 and R 23 , R 23 and R 24 , R 24 and R 25 , R 25 and R 26 may be bonded to each other to form a cyclic structure. R 7 and R 8 The ring structure formed by the bonding of R contains a boron atom and four carbon atoms as ring skeletal constituent atoms. 17 and R 18 The ring structure formed by bonding is X 1 When X is a boron atom, the ring structure contains a boron atom and four carbon atoms. 1 When R is a nitrogen atom, the cyclic structure is limited to a pyrrole ring. 21 and R 22 The ring structure formed by bonding is X 2 When X is a boron atom, the ring structure contains a boron atom and four carbon atoms. 2 When R is a nitrogen atom, the cyclic structure is limited to a pyrrole ring. 7 and R 8 , R 17 and R 18, R 21 and R 22 When R are bonded to each other to form a cyclic structure containing a boron atom, the cyclic structure is preferably a 5- to 7-membered ring, more preferably a 5- or 6-membered ring, and even more preferably a 6-membered ring. 7 and R 8 , R 17 and R 18 , R 21 and R 22 When they bond to each other, they bond to each other to form a single bond, -O-, -S-, -N(R 27 )-, -C(R 28 )(R 29 )-, -Si(R 30 )(R 31 )-, -B(R 32 )-, -CO-, -CS-, and preferably forms -O-, -S- or -N(R 27 )-, and more preferably -N(R 27 It is more preferred to form a )-, where R 27 ~R 32 Each of R independently represents a hydrogen atom, a deuterium atom, or a substituent. The substituent may be a group selected from any of the substituent groups A to E described below, but is preferably a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group, and particularly preferably R 27 is preferably a substituted or unsubstituted aryl group. 27 ~R 32 When is a substituent, R 7 and R 8 R in the ring formed by bonding together 27 ~R 32 is R 6 and R 9 may further bond to at least one of R to form a cyclic structure, 17 and R 18 R in the ring formed by bonding together 27 ~R 32 is R 16 and R 19 may further bond to at least one of R to form a cyclic structure, 21 and R 22R in the ring formed by bonding together 27 ~R 32 is R 20 and R 23 In one embodiment of the present invention, R 7 and R 8 , R 17 and R 18 , R 21 and R 22 In one embodiment of the present invention, only one pair of R 7 and R 8 , R 17 and R 18 , R 21 and R 22 In one embodiment of the present invention, only two pairs of R 7 and R 8 , R 17 and R 18 , R 21 and R 22 All of these are connected to each other.

[0062] R 1 and R 2 , R 2 and R 3 , R 3 and R 4 , R 4 and R 5 , R 5 and R 6 , R 6 and R 7 , R 8 and R 9 , R 9 and R 10 , R 10 and R 11 , R 11 and R 12 , R 13 and R 14 , R 14 and R 15 , R 15 and R 16 , R 16 and R 17 , R 18 and R 19 , R 19 and R 20 , R 20 and R21 , R 22 and R 23 , R 23 and R 24 , R 24 and R 25 , R 25 and R 26 The cyclic structure formed by bonding together may be an aromatic ring or an aliphatic ring, may contain a heteroatom, and may further be fused with one or more other rings. The heteroatom here is preferably selected from the group consisting of a nitrogen atom, an oxygen atom, and a sulfur atom. Examples of the cyclic structure formed include a benzene ring, a pyridine ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring, a pyrrole ring, an imidazole ring, a pyrazole ring, a triazole ring, an imidazoline ring, a furan ring, a thiophene ring, an oxazole ring, an isoxazole ring, a thiazole ring, an isothiazole ring, a cyclohexadiene ring, a cyclohexene ring, a cyclopentene ring, a cycloheptatriene ring, a cycloheptadiene ring, a cycloheptene ring, and a ring further fused with one or more rings selected from the group consisting of these rings. In a preferred embodiment of the present invention, the cyclic structure is a substituted or unsubstituted benzene ring (which may be further fused with a ring), for example, a benzene ring optionally substituted with an alkyl group or an aryl group. In a preferred embodiment of the present invention, the cyclic structure is a substituted or unsubstituted heteroaromatic ring, preferably a furan ring of benzofuran or a thiophene ring of benzothiophene. 1 and R 2 , R 2 and R 3 , R 3 and R 4 , R 4 and R 5 , R 5 and R 6 , R 6 and R 7 , R 8 and R 9 , R 9 and R 10 , R 10 and R 11 , R 11 and R 12 , R 13 and R 14 , R14 and R 15 , R 15 and R 16 , R 16 and R 17 , R 18 and R 19 , R 19 and R 20 , R 20 and R 21 , R 22 and R 23 , R 23 and R 24 , R 24 and R 25 , R 25 and R 26 Among these, the number of combinations that are bonded to each other to form a cyclic structure may be 0, or may be, for example, any of 1 to 6. For example, it may be any of 1 to 4, and 1, 2, 3, or 4 may be selected. In one embodiment of the present invention, R 1 and R 2 , R 2 and R 3 , R 3 and R 4 In one embodiment of the present invention, a pair of R 5 and R 6 are bonded to each other to form a ring structure. 9 and R 10 , R 10 and R 11 , R 11 and R 12 In one embodiment of the present invention, a pair of R 1 and R 2 , R 13 and R 14 are bonded to each other to form a cyclic structure. 1 and R 2 , R 2 and R 3 , R 3 and R 4 are bonded to each other to form a cyclic structure, and R 5 and R 6are bonded to each other to form a ring structure. 5 and R 6 , R 19 and R 20 are all bonded to each other to form a ring structure.

[0063] Adjacent R n (n=1-26) and R that are not bonded to each other 1 ~R 26 is a hydrogen atom, a deuterium atom, or a substituent. As the substituent, a group selected from any one of the groups A to E of substituents described below can be used. R 1 ~R 26 Preferred substituents that R may have are substituted or unsubstituted alkyl groups, substituted or unsubstituted aryl groups, and substituted or unsubstituted heteroaryl groups. For example, the substituent may be a substituted or unsubstituted aryl group, or for example, the substituent may be a substituted or unsubstituted alkyl group. The substituents of the alkyl group, aryl group, and heteroaryl group mentioned here can also be groups selected from any of the substituent groups A to E, but are preferably one or more groups selected from the group consisting of alkyl groups, aryl groups, and heteroaryl groups, and more preferably groups from the substituent group E, which may be unsubstituted. In one preferred embodiment of the present invention, R 1 ~R 6 At least one of R is a substituent, preferably a group of the substituent group E. For example, R 2 ~R 6 At least one of R is a substituent, preferably a group of the substituent group E. For example, R 5 and R 6 At least one of R is a substituent, preferably a group of the substituent group E. In a preferred embodiment of the present invention, 3 and R 6 At least one of X is a substituent, more preferably both are substituents, and are preferably groups in the substituent group E. In a preferred embodiment of the present invention, 1 is a nitrogen atom, R 15 and R 20At least one of R is a substituent, more preferably both are substituents, and are preferably groups in the substituent group E. 17 and R 18 In a preferred embodiment of the present invention, X 2 is a nitrogen atom, R 19 and R 24 At least one of R is a substituent, more preferably both are substituents, and are preferably groups in the substituent group E. 21 and R 22 are bonded to each other to form a single bond. 8 and R 12 In one aspect of the present invention, at least one of R 8 , R 10 and R 12 is a substituent. 8 ~R 12 The substituent of R is preferably an unsubstituted alkyl group. 8 and R 12 When R is an alkyl group having 2 or more carbon atoms (preferably an alkyl group having 3 or more carbon atoms, more preferably an alkyl group having 3 to 8 carbon atoms, and even more preferably an alkyl group having 3 or 4 carbon atoms), the orientation becomes high when the film is formed, which is preferable. 8 and R 12 is a substituent (preferably an alkyl group, more preferably an alkyl group having 2 or more carbon atoms, even more preferably an alkyl group having 3 or more carbon atoms, still more preferably an alkyl group having 3 to 8 carbon atoms, particularly preferably an alkyl group having 3 or 4 carbon atoms), and R 1 ~R 6 It is particularly preferred that at least one of X is a substituent (preferably a group in the substituent group E). 1 is a boron atom, R 13 and R 17 In one aspect of the present invention, at least one of X is a substituent, and preferably both are substituents. 1 is a boron atom, R 13 , R 15 and R 17 is a substituent. X 1is a boron atom, R 13 ~R 17 The substituent of X is preferably an unsubstituted alkyl group. 2 is a boron atom, R 22 and R 26 In one aspect of the present invention, at least one of X is a substituent, and preferably both are substituents. 2 is a boron atom, R 22 , R 24 and R 26 is a substituent. X 2 is a boron atom, R 22 ~R 26 The substituent of is preferably an unsubstituted alkyl group. 1 or X 2 Specific examples of groups bonded to boron atoms represented by are listed below. However, the groups bonded to boron atoms that can be used in the present invention should not be construed as being limited to the following specific examples. Note that in this specification, the notation CH3 for methyl groups is omitted. * indicates the bonding position. [ka]

[0064] In the following, R in general formula (G) 1 ~R 26 Here are some specific examples: R 1 ~R 7 , X 1 R when is a nitrogen atom 13 ~R 21 , X 2 R when is a nitrogen atom 18 ~R 26 is preferably Z1 to Z9, and R 8 ~R 12 , X 1 R when is a nitrogen atom 22 ~R 26 , X 2 R when is a nitrogen atom 13 ~R 17are preferably Z1 to Z7. However, the groups bonded to boron atoms that can be used in the present invention should not be construed as being limited by the following specific examples. D represents a deuterium atom. * represents the bonding position. [ka]

[0065] A 1 and A 2 is a hydrogen atom, a deuterium atom, or a substituent. As the substituent, a group selected from any one of the groups A to E of substituents described below can be used. In a preferred embodiment of the present invention, A 1 and A 2 are each independently a hydrogen atom or a deuterium atom. For example, A 1 and A 2 is a hydrogen atom. For example, A 1 and A 2 is a deuterium atom. A 1 and A 2 One of A may be a substituent. 1 and A 2 Each of A may independently be a substituent. 1 and A 2 A preferred substituent that can be taken by the group is an acceptor group. The acceptor group is a group having a positive Hammett σp value. A 1 and A 2The acceptor group that can be adopted is more preferably a group having a Hammett σp value of greater than 0.2. Examples of groups having a Hammett σp value of greater than 0.2 include a cyano group, an aryl group substituted with at least a cyano group, a group containing a fluorine atom, and a substituted or unsubstituted heteroaryl group containing a nitrogen atom as a ring skeleton-constituting atom. The aryl group substituted with at least a cyano group may be substituted with a substituent other than a cyano group (e.g., an alkyl group or an aryl group), or may be an aryl group substituted only with a cyano group. The aryl group substituted with at least a cyano group is preferably a phenyl group substituted with at least a cyano group. The number of cyano groups substituted is preferably 1 or 2, for example, it may be 1 or 2. Examples of groups containing a fluorine atom include a fluorine atom, a fluorinated alkyl group, and an aryl group substituted with at least a fluorine atom or a fluorinated alkyl group. The fluorinated alkyl group is preferably a perfluoroalkyl group, preferably having 1 to 6 carbon atoms, more preferably 1 to 3 carbon atoms. Furthermore, a heteroaryl group containing a nitrogen atom as a ring skeleton-constituting atom may be a single ring or a fused ring in which two or more rings are fused. In the case of a fused ring, the number of rings after fusion is preferably 2 to 6, and can be selected from 2 to 4, or can be 2. Specific examples of rings constituting a heteroaryl group include a pyridine ring, a pyrimidine ring, a pyrazine ring, a triazine ring, a quinoline ring, an isoquinoline ring, a quinazoline ring, a quinoxaline ring, and a naphthyridine ring other than a quinazoline ring or a quinoxaline ring. The ring constituting the heteroaryl group may be substituted with a deuterium atom or a substituent, and examples of the substituent include one group selected from the group consisting of an alkyl group, an aryl group, and a heteroaryl group, or a group formed by combining two or more of these groups. A 1 and A 2 Among the possible acceptor groups, a cyano group is particularly preferred. In one aspect of the present invention, A 1 and A 2 In one embodiment of the present invention, at least one of A is an acceptor group.1 and A 2 In one embodiment of the present invention, only one of A is an acceptor group. 1 and A 2 In one embodiment of the present invention, both A and A are the same acceptor group. 1 and A 2 are different acceptor groups. 1 and A 2 is a cyano group. 1 and A 2 is a halogen atom, for example a bromine atom.

[0066] Specific examples of acceptor groups that can be used in the present invention are shown below. However, the acceptor groups that can be used in the present invention should not be construed as being limited by the following specific examples. In this specification, the notation CH3 for methyl groups is omitted. Therefore, for example, A15 indicates a group containing two 4-methylphenyl groups. Furthermore, "D" represents a deuterium atom. * indicates a bonding position. [ka] JPEG0007788702000069.jpg197170

[0067] In addition, X 1 is a nitrogen atom, and R 7 and R 8 are bonded via a nitrogen atom to form a six-membered ring, and R 21 and R 22 are bonded via a nitrogen atom to form a six-membered ring, and R 17 and R 18 When they are bonded to each other to form a single bond, R 1 ~R 6 At least one of R is a substituted or unsubstituted aryl group, or R 1 and R 2 , R 2 and R 3 , R 3 and R 4 , R 4 and R 5 , R5 and R 6 are bonded to each other to form an aromatic ring (a substituted or unsubstituted benzene ring which may be fused) or a heteroaromatic ring (preferably a furan ring of a substituted or unsubstituted benzofuran which may be fused, or a thiophene ring of a substituted or unsubstituted benzothiophene which may be fused). Also, X 1 is a boron atom, and X 2 is a nitrogen atom, and R 7 and R 8 , R 17 and R 18 When they are bonded to each other to form a ring structure containing a boron atom, the ring structure is a 5- to 7-membered ring, and when it is a 6-membered ring, R 7 and R 8 , R 17 and R 18 are bonded to each other to form -B(R 32 )-, -CO-, -CS- or -N(R 27 )- is formed. R 27 preferably represents a hydrogen atom, a deuterium atom or a substituent.

[0068] X in general formula (G) 1 When X in general formula (G) is a nitrogen atom, the compound of the present invention has the following skeleton (1a): 2 When is a nitrogen atom, the compounds of the present invention have the following skeleton (1b): [ka]

[0069] Each hydrogen atom in the skeletons (1a) and (1b) may be substituted with a deuterium atom or a substituent. Alternatively, the hydrogen atoms may be substituted with a linking group together with the adjacent hydrogen atom to form a cyclic structure. For details, see the corresponding R in general formula (G). 1 ~R 26 , A 1 , A 2can be referred to. Examples include compounds in which the phenyl groups bonded to the boron atoms in the skeletons (1a) and (1b) are all substituted with mesityl groups, 2,6-diisopropylphenyl groups, or 2,4,6-triisopropylphenyl groups. In one embodiment of the present invention, each hydrogen atom in the skeletons (1a) and (1b) is substituted with a linking group together with the adjacent hydrogen atom, so that a cyclic structure is not formed.

[0070] A preferred group of compounds having the skeleton (1a) includes compounds represented by the following general formula (1a): General formula (1a) [ka]

[0071] In the general formula (1a), Ar 1 ~Ar 4 R each independently represents a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, or a substituted or unsubstituted alkyl group, and for example, a substituted or unsubstituted aryl group can be preferably selected. 41 and R 42 Each of m1 and m2 independently represents an integer of 0 to 5, each of n1 and n3 independently represents an integer of 0 to 4, and each of n2 and n4 independently represents an integer of 0 to 3. A 1 , A 2 each independently represents a hydrogen atom, a deuterium atom, or a substituent. It is preferred that at least one of n1 to n4 is 1 or greater, and m1 and m2 each independently represent an integer of 1 to 5. In one embodiment of the present invention, n1 to n4 each independently represent an integer of 0 to 2. In a preferred embodiment of the present invention, at least one of n1 to n4 is 1 or greater, preferably at least one of n1 and n2 is 1 or greater, and at least one of n3 and n4 is 1 or greater. In one embodiment of the present invention, n1 and n3 each independently represent 1 or 2, and n2 and n4 are 0. In one embodiment of the present invention, n2 and n4 each independently represent 1 or 2, and n1 and n3 are 0. In one embodiment of the present invention, n1 to n4 each independently represent 1 or 2. In one embodiment of the present invention, n1 and n3 are equal, and n2 and n4 are equal. In one embodiment of the present invention, n1 and n3 are 1, and n2 and n4 are 0. In one embodiment of the present invention, n1 and n3 are 0, and n2 and n4 are 1. In one embodiment of the present invention, n1 to n4 are all 1. Ar 1 ~Ar 4 The bonding position of Ar may be at least one of the 3- and 6-positions, at least one of the 2- and 7-positions, at least one of the 1- and 8-positions, or at least one of the 4- and 5-positions of the carbazole ring. 1 ~Ar 4 The bonding positions of may be both the 3- and 6-positions, both the 2- and 7-positions, both the 1- and 8-positions, or both the 4- and 5-positions of the carbazole ring. For example, at least one of the 3- and 6-positions can be preferably selected, or both the 3- and 6-positions can be more preferably selected. In a preferred embodiment of the present invention, Ar 1 ~Ar 4 In a preferred embodiment of the present invention, all of Ar 1 ~Ar 4 are each independently a substituted or unsubstituted aryl group, more preferably a substituted or unsubstituted phenyl group or naphthyl group, and even more preferably a substituted or unsubstituted phenyl group. Examples of the substituent include a group selected from any of the substituent groups A to E described below, but an unsubstituted phenyl group is also preferred. Ar 1 ~Ar 4 Preferred specific examples of the group include a phenyl group, an o-biphenyl group, an m-biphenyl group, a p-biphenyl group, and a terphenyl group. In one embodiment of the present invention, m1 and m2 are each independently 0. In one embodiment of the present invention, m1 and m2 are each independently an integer of 1 to 5. In one embodiment of the present invention, m1 and m2 are equal. In one embodiment of the present invention, R 41 and R 42 is an alkyl group having 1 to 6 carbon atoms, and can be selected from alkyl groups having 1 to 3 carbon atoms, for example, or a methyl group. The substitution positions of the alkyl group, with the carbon atom bonded to the boron atom being the 1st position, can be exemplified by the 2nd position only, the 3rd position only, the 4th position only, the 3rd and 5th positions, the 2nd and 4th positions, the 2nd and 6th positions, and the 2nd, 4th and 6th positions, preferably at least the 2nd position, and more preferably at least the 2nd and 6th positions. A 1 and A 2 For the explanation and preferred range of , the corresponding description of general formula (G) can be referred to.

[0072] Specific examples of the compound represented by general formula (1a) are listed below. The compounds of general formula (1a) that can be used in the present invention are not limited to the specific examples listed below. For example, a preferred group can be the group consisting of the remaining compounds excluding the compound in the center of the fourth row and the compound in the center of the eighth row listed below. [ka] JPEG0007788702000073.jpg230162JPEG0007788702000074.jpg230160JPEG0007788702000075.jpg219170 JPEG0007788702000076.jpg230164JPEG0007788702000077.jpg230159JPEG0007788702000078.jpg122170

[0073] Another group of specific examples of the compound represented by general formula (1a) is shown below. The compounds of general formula (1a) that can be used in the present invention are not to be construed as being limited by the following group of specific examples. [ka] JPEG0007788702000080.jpg230160JPEG0007788702000081.jpg221170JPEG0007788702 000082.jpg230155JPEG0007788702000083.jpg186170JPEG0007788702000084.jpg66170

[0074] A preferred group of compounds having the skeleton (1b) includes compounds represented by the following general formula (1b). General formula (1b) [ka]

[0075] In the general formula (1b), Ar 5 ~Ar 8 R each independently represents a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, or a substituted or unsubstituted alkyl group, and for example, a substituted or unsubstituted aryl group can be preferably selected. 43 and R 44 each independently represents a substituted or unsubstituted alkyl group. m3 and m4 each independently represents an integer of 0 to 5, n6 and n8 each independently represents an integer of 0 to 3, and n5 and n7 each independently represents an integer of 0 to 4. A 1 , A 2 each independently represents a hydrogen atom, a deuterium atom, or a substituent. 5 ~Ar 8 , R 43 and R 44 , m3 and m4, n5~n8, A 1 , A 2 For details, see Ar in general formula (1a). 1 ~Ar 4 , R 41 and R 42 , m1 and m2, n1 to n4, A 1 , A 2It is preferable that at least one of n5 to n8 is 1 or more, and m3 and m4 each independently represent an integer of 1 to 5.

[0076] Specific examples of the compound represented by general formula (1b) are listed below. The compounds of general formula (1b) that can be used in the present invention are not to be construed as being limited by the following specific examples. [ka]

[0077] R in general formula (G) 7 and R 8 When these are bonded together to form N-Ph, the compounds of the present invention are 1 When is a nitrogen atom, for example, the following skeleton (2a) is obtained, and X 2 When is a nitrogen atom, for example, it has the following skeleton (2b): Ph is a phenyl group. Skeleton (2a) [ka]

[0078] Each hydrogen atom in the skeletons (2a) and (2b) may be substituted with a deuterium atom or a substituent. Alternatively, the hydrogen atoms may be substituted with a linking group together with the adjacent hydrogen atoms to form a cyclic structure. For details, see the corresponding R in general formula (G). 1 ~R 26 , A 1 , A 2 can be referred to. At least one hydrogen atom of the benzene ring constituting the carbazole partial structure contained in the skeleton (2a) is substituted with a substituted or unsubstituted aryl group. In one embodiment of the present invention, each hydrogen atom in the skeletons (2a) and (2b) is substituted with a linking group together with the adjacent hydrogen atom, so that a cyclic structure is not formed.

[0079] A preferred group of compounds having the skeleton (2a) includes compounds represented by the following general formula (2a): General formula (2a) [ka]

[0080] In the general formula (2a), Ar 9 ~Ar 14 Each independently represents a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, or a substituted or unsubstituted alkyl group, and for example, a substituted or unsubstituted aryl group can be preferably selected. n9, n11, n12, and n14 each independently represent an integer of 0 to 4, and n10 and n13 each independently represent an integer of 0 to 2. However, at least one of n9, n10, n12, and n13 is 1 or greater. A 1 , A 2 each independently represents a hydrogen atom, a deuterium atom, or a substituent. In one embodiment of the present invention, n9 to n14 each independently represent an integer of 0 to 2. In one embodiment of the present invention, at least one of n9 to n14 is 1 or greater; for example, n9 and n12 can be 1 or greater, or n10 and n13 can be 1 or greater. In a preferred embodiment of the present invention, at least one of n9, n10, n12, and n13 is 1 or greater. In one embodiment of the present invention, n9 and n12 each independently represent 1 or 2, and n10, n11, n13, and n14 each represent 0. In one embodiment of the present invention, n10 and n13 each independently represent 1 or 2, and n9, n11, n12, and n14 each represent 0. In one embodiment of the present invention, n9 and n12 each independently represent 1 or 2, and n10 and n13 each independently represent 1 or 2, and n11 and n14 each represent 0. In one embodiment of the present invention, n9 to n14 are all 1. Ar 9 ~Ar 14 The bonding positions of Ar may be the 3- and 6-positions of the carbazole ring or other positions. 9 ~Ar 14 are all the same group. 9 ~Ar 14 For preferred groups, Ar 1 ~Ar 4Reference can be made to the corresponding description in A. 1 and A 2 For the explanation and preferred range of , the corresponding description of general formula (G) can be referred to.

[0081] Specific examples of the compound represented by general formula (2a) are listed below. The compounds of general formula (2a) that can be used in the present invention are not to be construed as being limited by the following specific examples. [ka]

[0082] A preferred group of compounds having the skeleton (2b) includes compounds represented by the following general formula (2b). General formula (2b) [ka]

[0083] In the general formula (2b), Ar 15 ~Ar 20 Each independently represents a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, or a substituted or unsubstituted alkyl group, and for example, a substituted or unsubstituted aryl group can be preferably selected. n15, n17, n18, and n20 each independently represent an integer of 0 to 4, and n16 and n19 each independently represent an integer of 0 to 2. A 1 , A 2 each independently represents a hydrogen atom, a deuterium atom, or a substituent. 15 ~Ar 20 , n15~n20, A 1 , A 2 For details, see Ar in general formula (2a). 9 ~Ar 14 , n9~n14, A 1 , A 2 The following descriptions can be referred to in order.

[0084] Specific examples of the compound represented by general formula (2b) are listed below. The compounds of general formula (2b) that can be used in the present invention are not to be construed as being limited by the following specific examples. [ka]

[0085] R in general formula (G) 7 and R 8 are bonded to each other to form a single bond, the compounds of the present invention are 1 When is a nitrogen atom, for example, the following skeleton (3a) is obtained, and X 2 When is a nitrogen atom, for example, it has the following skeleton (3b). [ka]

[0086] Each hydrogen atom in the skeletons (3a) and (3b) may be substituted with a deuterium atom or a substituent. Alternatively, the hydrogen atoms may be substituted with a linking group together with the adjacent hydrogen atom to form a cyclic structure. For details, see the corresponding R in general formula (G). 1 ~R 26 , A 1 , A 2 In one embodiment of the present invention, each hydrogen atom in the skeletons (3a) and (3b) is substituted with a linking group together with the adjacent hydrogen atom to form no cyclic structure.

[0087] A preferred group of compounds having the skeleton (3a) includes compounds represented by the following general formula (3a): General formula (3a) [ka]

[0088] In the general formula (3a), Ar 21 ~Ar 26Each of n21, n23, n24, and n26 independently represents an integer of 0 to 4, and each of n22 and n25 independently represents an integer of 0 to 2. A 1 , A 2 each independently represents a hydrogen atom, a deuterium atom, or a substituent. 21 ~Ar 25 For details of n21 to n25, see Ar 9 ~Ar 14 , n9~n14, A 1 , A 2 The following description can be referred to.

[0089] Specific examples of the compound represented by general formula (3a) are given below. The compounds of general formula (3a) that can be used in the present invention are not to be construed as being limited by the following specific examples. [ka]

[0090] A preferred group of compounds having the skeleton (3b) includes compounds represented by the following general formula (3b). General formula (3b) [ka]

[0091] In the general formula (3b), Ar 27 ~Ar 32 Each of n27, n29, n30, and n32 independently represents an integer of 0 to 4, and each of n28 and n31 independently represents an integer of 0 to 2. A 1 , A 2each independently represents a hydrogen atom, a deuterium atom, or a substituent. 27 ~Ar 32 , n27~n32, A 1 , A 2 For details, see Ar in general formula (2b). 15 ~Ar 20 , n15~n20, A 1 , A 2 The following descriptions can be referred to in order.

[0092] Specific examples of the compound represented by general formula (3b) are listed below. The compounds of general formula (3b) that can be used in the present invention are not to be construed as being limited by the following specific examples. [ka]

[0093] In a preferred embodiment of the present invention, a compound in which another ring is fused to the two benzene rings constituting the carbazole moiety present in general formula (G) is selected. Among them, a compound in which a benzofuran ring is fused, a compound in which a benzothiophene ring is fused, or a compound in which a benzene ring is fused can be particularly preferably selected. Below, these ring-fused compounds will be described with specific examples.

[0094] Preferred examples of such compounds include compounds in which a benzofuran ring or a benzothiophene ring is fused to the benzene ring that is not directly bonded to a boron atom, out of the two benzene rings constituting the carbazole moiety in general formula (G). Examples of such compounds include compounds having the following skeleton (4a) and compounds having the following skeleton (4b). [ka]

[0095] In skeletons (4a) and (4b), Y 1 ~Y 4 are each independently two hydrogen atoms, a single bond, or N(R 27) The two hydrogen atoms here indicate that the two benzene rings bonded to the boron atom are not linked to each other. Y 1 and Y 2 is the same as Y 3 and Y 4 are preferably the same, but may be different. 1 ~Y 4 is a single bond. In one aspect of the present invention, Y 1 ~Y 4 is N(R 27 ) R 27 represents a hydrogen atom, a deuterium atom or a substituent. Z 1 ~Z 4 each independently represents an oxygen atom or a sulfur atom. 1 and Z 2 are the same, and Z 3 and Z 4 are preferably the same, but may be different. 1 ~Z 4 is an oxygen atom. In this case, the furan ring of benzofuran is fused to the benzene ring constituting the carbazole moiety in (4a) and (4b). The orientation of the fused furan ring is not limited. In one embodiment of the present invention, Z 1 ~Z 4 is a sulfur atom. In this case, the thiophene ring of the benzothiophene is fused to the benzene ring that constitutes the carbazole moiety in (4a) and (4b). The orientation of the fused thiophene ring is not restricted. Each hydrogen atom in the skeletons (4a) and (4b) may be substituted with a deuterium atom or a substituent. Alternatively, the hydrogen atoms may be substituted with a linking group together with the adjacent hydrogen atom to form a cyclic structure. For details, see the corresponding R in general formula (G). 1 ~R 26 , A 1 , A 2 In one embodiment of the present invention, each hydrogen atom in the skeletons (4a) and (4b) is substituted with a linking group together with the adjacent hydrogen atom to form a ring structure.

[0096] A preferred group of compounds having the skeleton (4a) includes compounds represented by the following general formula (4a). X in the specific examples is an oxygen atom or a sulfur atom, and compounds in which X is an oxygen atom and compounds in which X is a sulfur atom are both considered to be disclosed. X in the specific examples of compounds represented by other general formulas below also has the same meaning. General formula (4a) [ka]

[0097] In the general formula (4a), Ar 51 and Ar 52 R each independently represents a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, or a substituted or unsubstituted alkyl group, and for example, a substituted or unsubstituted aryl group can be preferably selected. 51 and R 52 Each of m51 and m52 independently represents an integer of 0 to 4. Each of n51 and n52 independently represents an integer of 0 to 2. Y 1 ~Y 4 are each independently two hydrogen atoms, a single bond, or N(R 27 ) represents R 27 represents a hydrogen atom, a deuterium atom or a substituent. 1 ~Z 4 A each independently represents an oxygen atom or a sulfur atom. 1 , A 2 each independently represents a hydrogen atom, a deuterium atom, or a substituent. In one embodiment of the present invention, n51 and n52 are the same number. For example, n51 and n52 may be 0, or n51 and n52 may be 1. In one embodiment of the present invention, m51 and m52 are the same number. In one embodiment of the present invention, m51 and m52 are integers of 0 to 3. For example, m51 and m52 may be 0, m51 and m52 may be 1, m51 and m52 may be 2, or m51 and m52 may be 3. Ar 51 , Ar 52 , R51 , R 52 , A 1 , A 2 The preferred groups are Ar 1 ~Ar 4 , R 41 ~R 42 , A 1 , A 2 Reference can be made to the corresponding description in

[0098] Specific examples of the compound represented by general formula (4a) are listed below. The compounds of general formula (4a) that can be used in the present invention are not limited to the following group of specific examples. Regarding specific examples containing X, compounds in which all Xs in the molecule are oxygen atoms and compounds in which all Xs in the molecule are sulfur atoms are considered to be disclosed. Compounds in which some of the Xs in the molecule are oxygen atoms and the rest are sulfur atoms can also be used. [ka] JPEG0007788702000100.jpg204170JPEG0007788702000101.jpg191170JPEG00077887020 00102.jpg230154JPEG0007788702000103.jpg202170JPEG0007788702000104.jpg196170

[0099] Another group of specific examples of the compound represented by general formula (4a) is shown below. The compounds of general formula (4a) that can be used in the present invention are not to be construed as being limited by the following group of specific examples. [ka] JPEG0007788702000106.jpg185170

[0100] A preferred group of compounds having the skeleton (4b) includes compounds represented by the following general formula (4b). General formula (4b) [ka]

[0101] In the general formula (4b), Ar 53 and Ar 54 R each independently represents a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, or a substituted or unsubstituted alkyl group, and for example, a substituted or unsubstituted aryl group can be preferably selected. 53 and R 54 Each of m53 and m54 independently represents an integer of 0 to 4. Each of n53 and n54 independently represents an integer of 0 to 2. Y 3 and Y 4 are each independently two hydrogen atoms, a single bond, or N(R 27 ) represents R 27 represents a hydrogen atom, a deuterium atom or a substituent. 3 and Z 4 A each independently represents an oxygen atom or a sulfur atom. 1 , A 2 each independently represents a hydrogen atom, a deuterium atom, or a substituent. 53 , Ar 54 , R 53 , R 54 , m53, m54, n53, n54, A 1 , A 2 For details, see Ar in general formula (4a). 51 , Ar 52 , R 51 , R 52 , m51, m52, n51, n52, A 1 , A 2 The following description can be referred to.

[0102] Specific examples of the compound represented by general formula (4b) are listed below. The compounds of general formula (4b) that can be used in the present invention are not limited to the specific examples below. Regarding specific examples containing X, compounds in which all Xs in the molecule are oxygen atoms and compounds in which all Xs in the molecule are sulfur atoms are considered to be disclosed. Compounds in which some of the Xs in the molecule are oxygen atoms and the rest are sulfur atoms can also be used. [ka]

[0103] Preferred examples of such compounds include compounds in which a benzofuran ring or a benzothiophene ring is fused to the benzene ring directly bonded to a boron atom among the two benzene rings constituting the carbazole moiety present in general formula (G). Examples of such compounds include a compound having the following skeleton (5a) and a compound having the following skeleton (5b). [ka]

[0104] In skeletons (5a) and (5b), Y 5 ~Y 8 are each independently two hydrogen atoms, a single bond, or N(R 27 ) represents Z. 5 ~Z 8 Each of Y independently represents an oxygen atom or a sulfur atom. 5 ~Y 8 , Z 5 ~Z 8 For details of the skeletons (4a) and (4b), please refer to the corresponding descriptions of the skeletons (4a) and (4b). In one embodiment of the present invention, each hydrogen atom in the skeletons (5a) and (5b) is substituted with a linking group together with the adjacent hydrogen atom to form no cyclic structure.

[0105] A preferred group of compounds having the skeleton (5a) includes compounds represented by the following general formula (5a): General formula (5a) [ka]

[0106] In the general formula (5a), Ar 55 and Ar 56 R each independently represents a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, or a substituted or unsubstituted alkyl group, and for example, a substituted or unsubstituted aryl group can be preferably selected. 55 and R 56 Each of m55 and m56 independently represents an integer of 0 to 4. Each of n55 and n56 independently represents an integer of 0 to 4. Y 5 and Y 6 are each independently two hydrogen atoms, a single bond, or N(R 27 ) represents R 27 represents a hydrogen atom, a deuterium atom or a substituent. 5 and Z 6 A each independently represents an oxygen atom or a sulfur atom. 1 , A 2 each independently represents a hydrogen atom, a deuterium atom, or a substituent. In one embodiment of the present invention, n55 and n56 are integers of 0 to 2. For example, n55 and n56 may be 0, or n55 and n56 may be 1. In one embodiment of the present invention, m51 and m52 are the same number. For details of m55 and m56, the description of m51 and m52 in general formula (4a) can be referred to. Ar 55 , Ar 56 , R 55 , R 56 , A 1 , A 2 The preferred groups are Ar 1 , Ar 3 , R 41 , R 42 , A 1 , A 2 Reference can be made to the corresponding description in

[0107] Specific examples of the compound represented by general formula (5a) are listed below. The compounds of general formula (5a) that can be used in the present invention are not limited to the following group of specific examples. Regarding specific examples containing X, compounds in which all Xs in the molecule are oxygen atoms and compounds in which all Xs in the molecule are sulfur atoms are considered to be disclosed. Compounds in which some of the Xs in the molecule are oxygen atoms and the rest are sulfur atoms can also be used. [ka] JPEG0007788702000112.jpg200170JPEG0007788702000113.jpg194170JPEG0007788702000114.jpg197170JPEG0007788702000115.jpg223170

[0108] Another group of specific examples of the compound represented by general formula (5a) is shown below. The compounds of general formula (5a) that can be used in the present invention are not to be construed as being limited by the following group of specific examples. [ka]

[0109] A preferred group of compounds having the skeleton (5b) includes compounds represented by the following general formula (5b). General formula (5b) [ka]

[0110] In the general formula (5b), Ar 57 and Ar 58 R each independently represents a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, or a substituted or unsubstituted alkyl group, and for example, a substituted or unsubstituted aryl group can be preferably selected. 57 and R 58Each of m57 and m58 independently represents an integer of 0 to 4. Each of n57 and n58 independently represents an integer of 0 to 4. Y 7 and Y 8 are each independently two hydrogen atoms, a single bond, or N(R 27 ) represents R 27 represents a hydrogen atom, a deuterium atom or a substituent. 7 and Z 8 A each independently represents an oxygen atom or a sulfur atom. 1 , A 2 each independently represents a hydrogen atom, a deuterium atom, or a substituent. 57 , Ar 58 , R 57 , R 58 , m57, m58, n57, n58, A 1 , A 2 For details, see Ar in general formula (5a). 55 , Ar 56 , R 55 , R 56 , m55, m56, n55, n56, A 1 , A 2 The following description can be referred to.

[0111] Specific examples of the compound represented by general formula (5b) are listed below. The compounds of general formula (5b) that can be used in the present invention are not limited to the following group of specific examples. Regarding specific examples containing X, compounds in which all Xs in the molecule are oxygen atoms and compounds in which all Xs in the molecule are sulfur atoms are considered to be disclosed. Compounds in which some of the Xs in the molecule are oxygen atoms and the rest are sulfur atoms can also be used. [ka]

[0112] Another group of specific examples of the compound represented by general formula (5b) is shown below. The compounds of general formula (5b) that can be used in the present invention are not to be construed as being limited by the following group of specific examples. [ka]

[0113] Preferred examples of such compounds include compounds in which a benzofuran ring or a benzothiophene ring is fused to both of the two benzene rings constituting the carbazole moiety present in general formula (G). Examples of such compounds include a compound having the following skeleton (6a) and a compound having the following skeleton (6b). [ka]

[0114] In skeletons (6a) and (6b), Y 9 ~Y 12 are each independently two hydrogen atoms, a single bond, or N(R 27 ) represents Z. 9 ~Z 16 each independently represents an oxygen atom or a sulfur atom. 9 ~Z 16 are preferably the same, but may be different. 9 ~Z 16 is an oxygen atom. In one embodiment of the present invention, Z 9 ~Z 16 is a sulfur atom. Y 9 ~Y 12 For details of the skeletons (4a) and (4b), please refer to the corresponding descriptions of the skeletons (4a) and (4b). In one embodiment of the present invention, each hydrogen atom in the skeletons (6a) and (6b) is substituted with a linking group together with the adjacent hydrogen atom to form no cyclic structure.

[0115] A preferred group of compounds having the skeleton (6a) includes compounds represented by the following general formula (6a): General formula (6a) [ka]

[0116] In general formula (6a), R 59and R 60 Each of m59 and m60 independently represents an integer of 0 to 4. Y 9 and Y 10 are each independently two hydrogen atoms, a single bond, or N(R 27 ) represents R 27 represents a hydrogen atom, a deuterium atom or a substituent. 9 ~Z 12 A each independently represents an oxygen atom or a sulfur atom. 1 , A 2 R each independently represents a hydrogen atom, a deuterium atom, or a substituent. 59 , R 60 , m59, m60, Z 9 ~Z 12 , A 1 , A 2 For details, see R in general formula (5a). 55 , R 56 , m55, m56, A 1 , A 2 and Z in skeleton (6a) 9 ~Z 12 The following description can be referred to.

[0117] Specific examples of the compound represented by general formula (6a) are listed below. The compounds of general formula (6a) that can be used in the present invention are not limited to the specific examples below. Regarding specific examples containing X, compounds in which all Xs in the molecule are oxygen atoms and compounds in which all Xs in the molecule are sulfur atoms are considered to be disclosed. Compounds in which some of the Xs in the molecule are oxygen atoms and the rest are sulfur atoms can also be used. [ka] JPEG0007788702000123.jpg208170JPEG0007788702000124.jpg215170JPEG0007788702000125.jpg215170JPEG0007788702000126.jpg210170

[0118] A preferred group of compounds having the skeleton (6b) includes compounds represented by the following general formula (6b). General formula (6b) [ka]

[0119] In general formula (6b), R 61 and R 62 Each of m61 and m60 independently represents an integer of 0 to 4. Y 11 and Y 12 are each independently two hydrogen atoms, a single bond, or N(R 27 ) represents R 27 represents a hydrogen atom, a deuterium atom or a substituent. 13 ~Z 16 A each independently represents an oxygen atom or a sulfur atom. 1 , A 2 R each independently represents a hydrogen atom, a deuterium atom, or a substituent. 61 , R 62 , m61, m62, Z 13 ~Z 16 , A 1 , A 2 For details, see R in general formula (6a). 59 , R 60 , m59, m60, A 1 , A 2 and Z in skeleton (6b) 13 ~Z 16 The following description can be referred to.

[0120] Specific examples of the compound represented by general formula (6b) are listed below. The compounds of general formula (6b) that can be used in the present invention are not limited to the specific examples below. Regarding specific examples containing X, compounds in which all Xs in the molecule are oxygen atoms and compounds in which all Xs in the molecule are sulfur atoms are considered to be disclosed. Compounds in which some of the Xs in the molecule are oxygen atoms and the rest are sulfur atoms can also be used. [ka] JPEG0007788702000129.jpg252170JPEG0007788702000130.jpg241170

[0121] Preferred examples of such compounds include compounds in which a benzene ring is fused to the benzene ring to which the boron atom is not directly bonded, out of the two benzene rings constituting the carbazole moiety present in general formula (G). Examples of such compounds include a compound having the following skeleton (7a) and a compound having the following skeleton (7b). [ka]

[0122] In skeletons (7a) and (7b), Y 21 ~Y 24 are each independently two hydrogen atoms, a single bond, or N(R 27 ) Y 21 ~Y 24 For details, see Y in skeletons (4a) and (4b). 1 ~Y 4 In one embodiment of the present invention, each hydrogen atom in the skeletons (7a) and (7b) is substituted with a linking group together with the adjacent hydrogen atom to form a ring structure.

[0123] A preferred group of compounds having the skeleton (7a) includes compounds represented by the following general formula (7a): General formula (7a) [ka]

[0124] In the general formula (7a), Ar 71 ~Ar 74Each of n71 and n73 independently represents an integer of 0 to 2. Each of n72 and n74 independently represents an integer of 0 to 4. Y 21 and Y 22 are each independently two hydrogen atoms, a single bond, or N(R 27 ) represents R 27 represents a hydrogen atom, a deuterium atom or a substituent. 1 , A 2 each independently represents a hydrogen atom, a deuterium atom, or a substituent. In one embodiment of the present invention, n71 to n74 are integers of 0 to 2. In one embodiment of the present invention, n71 and n73 are the same number, and n72 and n74 are the same number. n71 to n74 may be the same number. For example, n71 to n74 may be 0. All of n71 to n74 may be 1. Also, for example, , n71 and n73 may be 0, and n72 and n74 may be 1. Ar 71 ~Ar 74 , A 1 , A 2 The preferred groups are Ar 1 ~Ar 4 , A 1 , A 2 Reference can be made to the corresponding description in

[0125] Specific examples of the compound represented by general formula (7a) are given below. The compounds of general formula (7a) that can be used in the present invention are not to be construed as being limited by the following specific examples. [ka]

[0126] A preferred group of compounds having the skeleton (7b) includes compounds represented by the following general formula (7b). General formula (7b) [ka]

[0127] In the general formula (7b), Ar 75 ~Ar 78 Each of n75 and n77 independently represents an integer of 0 to 2. Each of n76 and n78 independently represents an integer of 0 to 4. Y 23 and Y 24 are each independently two hydrogen atoms, a single bond, or N(R 27 ) represents R 27 represents a hydrogen atom, a deuterium atom, or a substituent. For a detailed explanation of n75 to n78, the descriptions of n71 to n74 in general formula (7a) can be referred to in order. Ar 75 ~Ar 78 The preferred groups are Ar 1 ~Ar 4 Reference can be made to the corresponding description in

[0128] Specific examples of the compound represented by general formula (7b) are given below. The compounds of general formula (7b) that can be used in the present invention are not to be construed as being limited by the following specific examples. [ka]

[0129] Preferred examples of such compounds include compounds in which a benzene ring is fused to the benzene ring directly bonded to a boron atom among the two benzene rings constituting the carbazole moiety present in general formula (G). Examples of such compounds include a compound having the following skeleton (8a) and a compound having the following skeleton (8b). [ka]

[0130] In skeletons (8a) and (8b), Y 25 ~Y 28 are each independently two hydrogen atoms, a single bond, or N(R 27 ) Y 25 ~Y 28 For details of the skeletons (4a) and (4b), please refer to the corresponding descriptions of the skeletons (4a) and (4b). In one embodiment of the present invention, each hydrogen atom in the skeletons (8a) and (8b) is substituted with a linking group together with the adjacent hydrogen atom to form no cyclic structure.

[0131] A preferred group of compounds having the skeleton (8a) includes compounds represented by the following general formula (8a): General formula (8a) [ka]

[0132] In the general formula (8a), Ar 79 and Ar 80 R each independently represents a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, or a substituted or unsubstituted alkyl group, and for example, a substituted or unsubstituted aryl group can be preferably selected. 71 and R 72 Each of m71 and m72 independently represents an integer of 0 to 4. Each of n79 and n80 independently represents an integer of 0 to 4. Y 25 and Y 26 are each independently two hydrogen atoms, a single bond, or N(R 27 ) represents R 27 represents a hydrogen atom, a deuterium atom or a substituent. 1 , A 2 each independently represents a hydrogen atom, a deuterium atom, or a substituent. In one embodiment of the present invention, n79 and n80 are integers of 0 to 2. In one embodiment of the present invention, n79 and n80 are the same number, and for example, both may be 0 or both may be 1. In one embodiment of the present invention, m71 and m72 are integers of 0 to 2. In one embodiment of the present invention, m71 and m72 are the same number, and for example, both may be 0 or both may be 1. Ar 79 , Ar 80 , R 71 , R 72 , A 1 , A 2 The preferred groups are Ar 1 , Ar 3 , R 41 , R 42 , A 1 , A 2 Reference can be made to the corresponding description in

[0133] Specific examples of the compound represented by general formula (8a) are given below. The compounds of general formula (8a) that can be used in the present invention are not to be construed as being limited by the following specific examples. [ka]

[0134] A preferred group of compounds having the skeleton (8b) includes compounds represented by the following general formula (8b). General formula (8b) [ka]

[0135] In the general formula (8b), Ar 81 and Ar 82 R each independently represents a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, or a substituted or unsubstituted alkyl group, and for example, a substituted or unsubstituted aryl group can be preferably selected. 73 and R 74Each of m73 and m74 independently represents an integer of 0 to 4. Each of n81 and n82 independently represents an integer of 0 to 4. Y 27 and Y 28 are each independently two hydrogen atoms, a single bond, or N(R 27 ) represents R 27 represents a hydrogen atom, a deuterium atom or a substituent. 1 , A 2 each independently represents a hydrogen atom, a deuterium atom, or a substituent. For a detailed explanation of m73, m74, n81, and n82, please refer to the descriptions of m71, m72, n79, and n80 in general formula (8a). 81 , Ar 82 , R 73 , R 74 , A 1 , A 2 The preferred groups are Ar 1 , Ar 3 , R 41 , R 42 , A 1 , A 2 Reference can be made to the corresponding description in

[0136] Specific examples of the compound represented by general formula (8b) are listed below. The compounds of general formula (8b) that can be used in the present invention are not to be construed as being limited by the following specific examples. [ka]

[0137] Preferred examples of such compounds include compounds in which a benzene ring is fused to both of the two benzene rings constituting the carbazole moiety present in general formula (G). Examples of such compounds include a compound having the following skeleton (9a) and a compound having the following skeleton (9b). [ka]

[0138] In skeletons (9a) and (9b), Y 29 ~Y 32 are each independently two hydrogen atoms, a single bond, or N(R 27 ) Y 29 ~Y 32 For details of the skeletons (4a) and (4b), please refer to the corresponding descriptions of the skeletons (4a) and (4b). In one embodiment of the present invention, each hydrogen atom in the skeletons (9a) and (9b) is substituted with a linking group together with the adjacent hydrogen atom to form no cyclic structure.

[0139] A preferred group of compounds having the skeleton (9a) includes compounds represented by the following general formula (9a): General formula (9a) [ka]

[0140] In general formula (9a), R 75 and R 76 Each of m75 and m76 independently represents an integer of 0 to 4. Y 29 and Y 30 are each independently two hydrogen atoms, a single bond, or N(R 27 ) represents R 27 represents a hydrogen atom, a deuterium atom or a substituent. 1 , A 2 R each independently represents a hydrogen atom, a deuterium atom, or a substituent. 75 , R 76 , m75, m76, A 1 , A 2 For details, see R in general formula (8a). 71 , R 72 , m71, m72, A 1 , A 2 The following description can be referred to.

[0141] Specific examples of the compound represented by general formula (9a) are given below. The compounds of general formula (9a) that can be used in the present invention are not to be construed as being limited by the following specific examples. [ka] JPEG0007788702000144.jpg57170

[0142] A preferred group of compounds having the skeleton (9b) includes compounds represented by the following general formula (9b). General formula (9b) [ka]

[0143] In general formula (9b), R 77 and R 78 Each of m77 and m78 independently represents an integer of 0 to 4. Y 31 and Y 32 are each independently two hydrogen atoms, a single bond, or N(R 27 ) represents R 27 represents a hydrogen atom, a deuterium atom or a substituent. 1 , A 2 R each independently represents a hydrogen atom, a deuterium atom, or a substituent. 77 , R 78 , m77, m78, A 1 , A 2 For details, see R in general formula (8a). 71 , R 72 , m71, m72, A 1 , A 2 The following description can be referred to.

[0144] Specific examples of the compound represented by general formula (9b) are given below. The compounds of general formula (9b) that can be used in the present invention are not to be construed as being limited by the following specific examples. [ka]

[0145] Compounds represented by general formula (G) are also preferred that contain four or more carbazole moieties in the molecule. Examples of such compounds include compounds having the following skeleton (10). Skeleton (10) [ka]

[0146] Each hydrogen atom in the skeleton (10) may be substituted with a deuterium atom or a substituent. Alternatively, the hydrogen atom may be substituted with a linking group together with the adjacent hydrogen atom to form a cyclic structure. For details, see the corresponding R in general formula (G). 1 ~R 26 , A 1 , A 2 can be referred to. At least one hydrogen atom of the benzene ring constituting the carbazole partial structure contained in the skeleton (10) is substituted with a substituted or unsubstituted aryl group. In one embodiment of the present invention, each hydrogen atom in the skeleton (10) is substituted with a linking group together with the adjacent hydrogen atom to form no cyclic structure.

[0147] A preferred group of compounds having the skeleton (10) includes compounds represented by the following general formula (10): General formula (10) [ka]

[0148] In the general formula (10), Ar 91 ~Ar 94Each of n91 and n93 independently represents an integer of 0 to 4, and n92 and n94 independently represent an integer of 0 to 3. The α ring, β ring, γ ring, and δ ring may be substituted, and at least one ring is substituted with a substituted or unsubstituted aryl group, or is fused with an optionally substituted benzene ring, or is fused with a furan ring of a substituted or unsubstituted benzofuran or a thiophene ring of a substituted or unsubstituted thiophene. A 1 , A 2 each independently represents a hydrogen atom, a deuterium atom, or a substituent. In one embodiment of the present invention, n91 to n94 are integers of 0 to 2. In one embodiment of the present invention, n91 and n93 are the same number, and n92 and n94 are the same number. n91 to n94 may all be the same number, for example, all may be 0 or all may be 1. Ar 91 ~Ar 94 The preferred groups are Ar 1 ~Ar 4Reference can be made to the corresponding description in the above. In one embodiment of the present invention, the α-ring and the γ-ring have the same substituent or the same fused structure, and the β-ring and the δ-ring have the same substituent or the same fused structure. In one embodiment of the present invention, the β-ring and the δ-ring are both substituted with a substituted or unsubstituted aryl group, are fused with an optionally substituted benzene ring, or are fused with a furan ring of a substituted or unsubstituted benzofuran or a thiophene ring of a substituted or unsubstituted thiophene. In one embodiment of the present invention, the α-ring and the γ-ring are both substituted with a substituted or unsubstituted aryl group, are fused with an optionally substituted benzene ring, or are fused with a furan ring of a substituted or unsubstituted benzofuran or a thiophene ring of a substituted or unsubstituted thiophene. In one embodiment of the present invention, all of the α-ring, the β-ring, the γ-ring, and the δ-ring are substituted with a substituted or unsubstituted aryl group, are fused with an optionally substituted benzene ring, or are fused with a furan ring of a substituted or unsubstituted benzofuran or a thiophene ring of a substituted or unsubstituted thiophene. A 1 and A 2 For the explanation and preferred range of , the corresponding description of general formula (G) can be referred to.

[0149] Specific examples of the compound represented by general formula (10) are given below. The compounds of general formula (10) that can be used in the present invention are not to be construed as being limited by the following specific examples. [ka] JPEG0007788702000150.jpg201170JPEG0007788702000151.jpg126170

[0150] The compound represented by general formula (G) may have an asymmetric skeleton, for example, a compound having an asymmetric skeleton such as the following skeleton (11a) or skeleton (11b). [ka]

[0151] In skeletons (11a) and (11b), Z 17 and Z 18 each independently represents an oxygen atom or a sulfur atom. In one embodiment of the present invention, each hydrogen atom in the skeletons (11a) and (11b) is substituted with a linking group together with the adjacent hydrogen atom to form no cyclic structure.

[0152] A preferred group of compounds having the skeleton (11a) includes compounds represented by the following general formula (11a). General formula (11a) [ka]

[0153] In the general formula (11a), Ar 83 ~Ar 85 R each independently represents a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, or a substituted or unsubstituted alkyl group, and for example, a substituted or unsubstituted aryl group can be preferably selected. 83 and R 84 Each of Z independently represents a substituted or unsubstituted alkyl group. 17 represents an oxygen atom or a sulfur atom. m83 and m84 each independently represent an integer of 0 to 5. n83 represents an integer of 0 to 4, and n84 and n85 each independently represent an integer of 0 to 3. Ar 83 ~Ar 85 , R 83 , R 84 For detailed explanations and preferred ranges of m83, m84, and n83 to n85, see Ar 1 , Ar 2 , Ar 4 , R 41 , R 42 , m1, m2, n1, n2, and n4.

[0154] Specific examples of the compound represented by general formula (11a) are given below. The compounds of general formula (11a) that can be used in the present invention should not be construed as being limited by the following specific examples. In the following specific examples, a compound in which all Xs in the molecule are oxygen atoms and a compound in which all Xs in the molecule are sulfur atoms are respectively disclosed. A compound in which some of the Xs in the molecule are oxygen atoms and the rest are sulfur atoms can also be used. [ka]

[0155] A preferred group of compounds having the skeleton (11b) includes compounds represented by the following general formula (11b). General formula (11b) [ka]

[0156] In the general formula (11b), Ar 86 ~Ar 88 R each independently represents a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, or a substituted or unsubstituted alkyl group, and for example, a substituted or unsubstituted aryl group can be preferably selected. 86 and R 87 Each of Z independently represents a substituted or unsubstituted alkyl group. 18 represents an oxygen atom or a sulfur atom. m86 and m87 each independently represent an integer of 0 to 5. n86 represents an integer of 0 to 4, and n87 and n88 each independently represent an integer of 0 to 3. Ar 86 ~Ar 88 , R 86 , R 87 For detailed explanations and preferred ranges of m86, m87, and n86 to n88, see Ar 1 , Ar 2 , Ar 4 , R 41 , R 42 , m1, m2, n1, n2, and n4.

[0157] Specific examples of the compound represented by general formula (11b) are given below. The compounds of general formula (11b) that can be used in the present invention should not be construed as being limited by the following specific examples. In the following specific examples, a compound in which all Xs in the molecule are oxygen atoms and a compound in which all Xs in the molecule are sulfur atoms are respectively disclosed. A compound in which some of the Xs in the molecule are oxygen atoms and the rest are sulfur atoms can also be used. [ka]

[0158] As the compound represented by general formula (G), R 5 A compound in which R is a donor group can be preferably used. 5 Compounds in which R is a donor group tend to have a high molar absorption coefficient and high luminescence efficiency. 3 In a preferred embodiment of the present invention, R 3 is not a donor group. In a preferred embodiment of the present invention, R 1 ~R 7 Among them, R 5 Only R is a donor group, or none of R is a donor group (especially a donor group with a σp value of -0.2 or less). A donor group is a group with a negative Hammett σp value. 5The donor group preferably has a σp value of -0.2 or less, for example, -0.4 or less, or for example, -0.6 or less. A preferred donor group is a substituted amino group, preferably a substituted or unsubstituted diarylamino group. The aryl group may be a monocyclic ring or a fused ring formed by condensing two or more rings. In the case of a fused ring, the number of rings after condensation is preferably 2 to 6, for example, selected from 2 to 4, or may be 2. The two aryl groups constituting the diarylamino group may be the same or different. The two aryl groups may be linked by a single bond or a linking group. A preferred substituted or unsubstituted diarylamino group is a substituted or unsubstituted diphenylamino group. A substituted or unsubstituted carbazol-9-yl group in which two phenyl groups are bonded by a single bond may be used, or a substituted or unsubstituted diphenylamino group in which two phenyl groups are not bonded by a single bond may be used. R in general formula (G) 1 ~R 7 When any of R is a substituted amino group, at least R 5 is preferably a substituted amino group, and R 5 More preferably, only R is a substituted amino group. 3 is not a substituted amino group. R 5 is a donor group, and X 1 is a nitrogen atom, R 16 or R 19 is preferably a donor group, and R 19 is more preferably a donor group. In this case, other R 1 ~R 26 may be, for example, all hydrogen atoms or all deuterium atoms, or may be, for example, R 3 , R 6 , R 15 , R 20 At least one of these may be a substituent (preferably a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group), and the others may be hydrogen atoms or deuterium atoms. R 5is a donor group, and X 1 is a boron atom, R 20 or R 23 is preferably a donor group, and R 20 is more preferably a donor group. In this case, other R 1 ~R 26 may be, for example, all hydrogen atoms or all deuterium atoms, or may be, for example, R 3 , R 6 , R 19 , R 24 At least one of these may be a substituent (preferably a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group), and the others may be hydrogen atoms or deuterium atoms. R 5 As a preferred group of compounds in which is a donor group, there can be mentioned compounds represented by the following general formula (12a) and compounds represented by the following general formula (12b). General formula (12a) [ka]

[0159] In the general formula (12a) and the general formula (12b), Ar 1 ~Ar 8 R each independently represents a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, or a substituted or unsubstituted alkyl group, and for example, a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group can be preferably selected. 5 represents a donor group. 41 ~R 44 each independently represents a substituted or unsubstituted alkyl group. m1 to m4 each independently represents an integer of 0 to 5. n1, n3, n5, and n7 each independently represent an integer of 0 to 4, n4 and n8 each independently represent an integer of 0 to 3, and n2' and n6' each independently represent an integer of 0 to 2. A 1 , A 2 each independently represents a hydrogen atom, a deuterium atom, or a substituent. 1 ~Ar 8 , R 41~R 44 , m1~m4, n1, n3~n5, n7, n8, A 1 , A 2 For details of the general formula (1a) and the general formula (1b), please refer to the corresponding descriptions. However, Ar 1 Ar bonded to adjacent carbon atoms 3 Ar bonded to adjacent carbon atoms 5 Ar bonded to adjacent carbon atoms 7 They may be bonded to each other to form a ring structure, preferably a benzofuran (fused with a furan ring) or a benzothiophene (fused with a thiophene ring).

[0160] Specific examples of compounds represented by general formula (12a) and general formula (12b) are listed below. However, the compounds of general formula (12a) and general formula (12b) that can be used in the present invention should not be construed as being limited by the following specific examples. In the following specific examples, the structure of each compound is defined by specifying R, Ar, and X in formulas F1 to F56 in the table. R is selected from A to D shown below, Ar is selected from a to d shown below, and X is selected from α to γ. For example, compound No. 1 in the table is a compound having a structure in which R is A and Ar is a in formula F1.

[0161] [ka] [ka] [ka] [ka] [ka] [ka] [Table 1] JPEG0007788702000165.jpg227167JPEG0007788702000166.jpg229168JPEG0007788702000167.jpg227166JPEG0007788702000168.jpg22716 6JPEG0007788702000169.jpg230166JPEG0007788702000170.jpg227166JPEG0007788702000171.jpg228167JPEG0007788702000172.jpg75169

[0162] [ka]

[0163] In one embodiment of the present invention, the above skeletons (1a) to (12b) are skeletons to which no other rings are further condensed. In another embodiment of the present invention, the above skeletons (1a) to (12b) are skeletons to which other rings may be further condensed. The other rings referred to here are those represented by the above R 1 and R 2 , R 2 and R 3 , R 3 and R 4 , R 4 and R 5 , R 5 and R 6 , R 6 and R 7 , R 8 and R 9 , R 9 and R 10 , R 10 and R 11 , R 11 and R 12 , R 13 and R 14 , R 14 and R 15 , R 15 and R 16 , R 16 and R 17 , R 18 and R 19 , R 19and R 20 , R 20 and R 21 , R 22 and R 23 , R 23 and R 24 , R 24 and R 25 , R 25 and R 26 The description of the cyclic structure formed by bonding together can be referred to.

[0164] In one embodiment of the present invention, A in general formula (G) 1 and A 2 is an acceptor group. For example, A 1 and A 2 The position of the acceptor group is an acceptor group, and examples thereof include compounds having any of the skeletons (1a) to (12b). For explanations and specific examples of the acceptor group, see A in the above general formula (G). 1 and A 2 The explanation and specific examples of the acceptor group can be referred to. In the following, A 1 and A 2 Specific examples of compounds in which A is an acceptor group are as follows: 1 and A 2 The compounds in which A is an acceptor group are not to be construed as being limited by the following specific examples. 1 and A 2 have a structure in which both are "A", and the structure of each compound is specified by individually specifying the "A". [ka] JPEG0007788702000175.jpg229160JPEG0007788702000176.jpg230161JPEG0007788702000177.jpg230157JPEG0007788702000178.jpg225163 JPEG0007788702000179.jpg227162JPEG0007788702000180.jpg230162JPEG0007788702000181.jpg228153JPEG0007788702000182.jpg125166

[0165] In one embodiment of the present invention, a compound having a rotationally symmetric structure is selected as the compound represented by general formula (G). In one embodiment of the present invention, a compound having an axisymmetric structure is selected as the compound represented by general formula (G). In one embodiment of the present invention, a compound having an asymmetric structure is selected as the compound represented by general formula (G). Specific examples of compounds having an asymmetric skeleton are listed below. Compounds having an asymmetric skeleton or compounds having an asymmetric structure that can be used in the present invention are not limited to the specific examples below. Regarding specific examples containing X, compounds in which all Xs in the molecule are oxygen atoms and compounds in which all Xs in the molecule are sulfur atoms are considered to be disclosed. Compounds in which some of the Xs in the molecule are oxygen atoms and the rest are sulfur atoms can also be used. [ka] JPEG0007788702000184.jpg224168JPEG0007788702000185.jpg229168JPEG0007788702000186.jpg111166

[0166] Specific examples of compounds that have a symmetrical skeleton but have an asymmetrical structure due to asymmetrically bonded substituents are given below. The compounds having an asymmetrical structure that can be used in the present invention should not be construed as being limited by the following specific examples. [ka] JPEG0007788702000188.jpg51166

[0167] In one aspect of the present invention, R in general formula (G) 3 is not a diarylamino group (two aryl groups constituting the diarylamino group may be bonded to each other). In a preferred embodiment of the present invention, R 3 is a hydrogen atom, a deuterium atom, or an acceptor group (not a donor group). In one embodiment of the present invention, at least one of n1 to n4 in general formula (1a) is 1 or greater. In a preferred embodiment of the present invention, at least one of m1 and m2 in general formula (1a) is 1 or greater. In a further preferred embodiment of the present invention, at least one of n1 to n4 in general formula (1a) is 1 or greater, and at least one of m1 and m2 in general formula (1a) is 1 or greater. In one embodiment of the present invention, at least one of n5 to n8 in general formula (1b) is 1 or greater. In a preferred embodiment of the present invention, at least one of m3 and m4 in general formula (1b) is 1 or greater. In a further preferred embodiment of the present invention, at least one of n5 to n8 in general formula (1b) is 1 or greater, and at least one of m3 and m4 in general formula (1a) is 1 or greater. When at least one of m1 and m2 is 1 or more, and at least one of m3 and m4 is 1 or more, R 41 and R 42 At least one of and R 43 and R 44 At least one of R is preferably an alkyl group optionally substituted with a deuterium atom, for example, R 41 ~R 44 When at least one of n1 to n4 is 1 or more and at least one of n5 to n8 is 1 or more, Ar 1 ~Ar 4 At least one of and Ar 5 ~Ar 8 At least one of the groups is preferably an aryl group which may be substituted with a deuterium atom or an alkyl group, for example, Ar 1~Ar 8 All of the above are aryl groups which may be substituted with a deuterium atom or an alkyl group. In one embodiment of the present invention, X in general formula (G) 1 is a boron atom and R 8 , R 10 , R 12 , R 13 , R 15 , R 17 When is an alkyl group (or a methyl group), R 1 ~R 7 , R 18 ~R 20 , R 23 ~R 26 At least one of X in general formula (G) is a substituent, preferably a group in the substituent group E, for example, an aryl group which may be substituted with a deuterium atom or an alkyl group. 2 is a boron atom and R 8 , R 10 , R 12 , R 22 , R 24 , R 26 When is an alkyl group (or a methyl group), R 1 ~R 7 , R 13 ~R 16 , R 19 ~R 21 At least one of these is a substituent, preferably a group in Substituent Group E, such as an aryl group optionally substituted with a deuterium atom or an alkyl group. In one embodiment of the present invention, X in general formula (G) 1 is a boron atom, and R 8 and R 9 , R 9 and R 10 and one pair of R 15 and R 16 , R 16 and R 17 When any pair of these bonds together to form an aromatic ring (or a benzene ring), R 1 ~R 7 , R 18 ~R 20 , R 23 ~R 26At least one of X in general formula (G) is a substituent, preferably a group in the substituent group E, for example, an aryl group which may be substituted with a deuterium atom or an alkyl group. 2 is a boron atom, and R 8 and R 9 , R 9 and R 10 and one pair of R 22 and R 23 , R 23 and R 24 When any pair of these bonds together to form an aromatic ring (or a benzene ring), R 1 ~R 7 , R 13 ~R 16 , R 19 ~R 21 At least one of these is a substituent, preferably a group in Substituent Group E, such as an aryl group optionally substituted with a deuterium atom or an alkyl group. In one aspect of the present invention, R in general formula (G) 9 and R 11 is neither a cyano group nor an alkyl group. 9 and R 11 is a hydrogen atom, a deuterium atom, or a substituent other than a cyano group and an alkyl group. 9 and R 11 is neither a cyano group nor a tert-butyl group. In a preferred embodiment of the present invention, R in general formula (G) 8 ~R 12 At least one of is a substituent. In one aspect of the present invention, R in general formula (G) 3 is not a substituted amino group or an aryl group. 3 is not a substituted amino group or a phenyl group. 3 is not a dimethylamino group, a diphenylamino group, or a phenyl group. In a preferred embodiment of the present invention, R in general formula (G) 1 ~R 26 At least one of is a substituent, more preferably R 1 ~R26 At least one of them is an alkyl group, for example, an alkyl group having 1 to 4 carbon atoms.

[0168] In one embodiment of the present invention, the compound represented by general formula (1) can be used together with other host materials to form an emitting layer (composition) containing multiple host materials. That is, in one embodiment of the present invention, the composition of the present invention contains multiple host materials including the compound represented by general formula (1). The composition of the present invention may contain multiple types of compounds represented by general formula (1), or may use a compound represented by general formula (1) in combination with a host material not represented by general formula (1). Preferred compounds that can be used as the second host material together with the compound represented by general formula (1) are listed below, but the second host material that can be used in the present invention should not be construed as being limited by these specific examples.

[0169] [ka] JPEG0007788702000190.jpg211166

[0170] The form of the composition of the present invention is not particularly limited. In a particularly preferred embodiment of the present invention, the composition of the present invention is in the form of a membrane (film). The membrane made of the composition of the present invention may be formed by a wet process or a dry process. In a wet process, a solution containing the composition of the present invention is applied to a surface, and after removing the solvent, a light-emitting layer is formed. Examples of wet processes include, but are not limited to, spin coating, slit coating, inkjet printing (spraying), gravure printing, offset printing, and flexographic printing. In a wet process, an appropriate organic solvent capable of dissolving the composition of the present invention is selected and used. In some embodiments, a substituent (e.g., an alkyl group) that increases the solubility in organic solvents can be introduced into the compound contained in the composition of the present invention. A vacuum deposition method can be preferably used as the dry process. When using a vacuum deposition method, the compounds constituting the composition of the present invention may be co-deposited from separate deposition sources, or from a single deposition source containing a mixture of all compounds. When a single deposition source is used, a mixed powder containing all the compounds may be used, or a compressed compact obtained by compressing the mixed powder may be used, or a mixture obtained by heating, melting, mixing, and then cooling may be used. In some embodiments, co-deposition is performed under conditions where the deposition rates (weight loss rates) of multiple compounds contained in a single deposition source are identical or nearly identical, thereby forming a film having a composition ratio corresponding to the composition ratio of multiple compounds contained in the deposition source. By mixing multiple compounds in the same composition ratio as the composition ratio of the film to be formed and using the deposition source as a deposition source, a film having a desired composition ratio can be easily formed. In some embodiments, the temperature at which each compound to be co-deposited has the same weight loss rate can be identified, and that temperature can be used as the temperature during co-deposition. When the film is formed by a vapor deposition method, the molecular weight of each compound constituting the composition is preferably 1500 or less, more preferably 1200 or less, even more preferably 1000 or less, and even more preferably 900 or less. The lower limit of the molecular weight may be, for example, 450, 500, or 600.

[0171] (organic light-emitting element) By forming a light-emitting layer made of the composition of the present invention, it is possible to provide excellent organic light-emitting devices such as organic photoluminescence devices (organic PL devices) and organic electroluminescence devices (organic EL devices). The organic light-emitting device of the present invention is a fluorescent light-emitting device, and the largest component of light emitted from the device is fluorescence (fluorescence here includes delayed fluorescence). The thickness of the light-emitting layer can be, for example, 1 to 15 nm, 2 to 10 nm, or 3 to 7 nm. An organic photoluminescent device has a structure in which at least an emitting layer is formed on a substrate. An organic electroluminescent device has a structure in which at least an anode, a cathode, and an organic layer are formed between the anode and the cathode. The organic layer includes at least an emitting layer, and may consist of only the emitting layer, or may have one or more organic layers in addition to the emitting layer. Examples of such other organic layers include a hole transport layer, a hole injection layer, an electron blocking layer, a hole blocking layer, an electron injection layer, an electron transport layer, and an exciton blocking layer. The hole transport layer may be a hole injection transport layer with hole injection function, and the electron transport layer may be an electron injection transport layer with electron injection function. A specific example of the structure of an organic electroluminescent device is shown in Figure 1. In Figure 1, 1 represents the substrate, 2 represents the anode, 3 represents the hole injection layer, 4 represents the hole transport layer, 5 represents the emitting layer, 6 represents the electron transport layer, and 7 represents the cathode. When the organic light-emitting element of the present invention is a multi-wavelength light-emitting organic light-emitting element, the emission with the shortest wavelength may include delayed fluorescence. Alternatively, the emission with the shortest wavelength may not include delayed fluorescence. When excited by thermal or electronic means, organic light-emitting devices using the compositions of the present invention can emit light in the ultraviolet region, the blue, green, yellow, orange, or red region of the visible spectrum (e.g., 420-500 nm, 500-600 nm, or 600-700 nm), or the near-infrared region. For example, organic light-emitting devices can emit light in the red or orange region (e.g., 620-780 nm). For example, organic light-emitting devices can emit light in the orange or yellow region (e.g., 570-620 nm). For example, organic light-emitting devices can emit light in the green region (e.g., 490-575 nm). For example, organic light-emitting devices can emit light in the blue region (e.g., 400-490 nm). For example, organic light-emitting devices can emit light in the ultraviolet spectral region (e.g., 280-400 nm). For example, organic light-emitting devices can emit light in the infrared spectral region (e.g., 780 nm-2 μm). The largest component of the light emitted from an organic light-emitting device using the composition of the present invention is preferably the light emitted from the delayed fluorescent material contained in the composition of the present invention. The light emitted from the compound represented by general formula (1) is preferably less than 10% of the light emitted from the organic light-emitting device, and may be, for example, less than 1%, less than 0.1%, less than 0.01%, or even below the detection limit. The light emitted from the delayed fluorescent material may be, for example, more than 50%, more than 90%, or more than 99% of the light emitted from the organic light-emitting device. When the layer containing the composition of the present invention (light-emitting layer) contains a fluorescent material as a third component, the largest component of the light emitted from the organic light-emitting device may be the light emitted from the fluorescent material. In this case, the light emitted from the light-emitting material may be, for example, more than 50%, more than 90%, or more than 99% of the light emitted from the organic light-emitting device.

[0172] Each component of the organic electroluminescence element and each layer other than the light-emitting layer will be described below.

[0173] Base material: In some embodiments, the organic electroluminescent device of the present invention is supported by a substrate, and the substrate is not particularly limited and may be any material commonly used in organic electroluminescent devices, such as glass, transparent plastic, quartz, and silicon.

[0174] anode: In some embodiments, the anode of the organic electroluminescent device is made of a metal, an alloy, a conductive compound, or a combination 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), SnO, and ZnO. In some embodiments, an amorphous material capable of forming a transparent conductive film, such as In2O3-ZnO, is used. In some embodiments, the anode is a thin film. In some embodiments, the thin film is formed by evaporation or sputtering. In some embodiments, the film is patterned by a photolithography method. In some embodiments, if the pattern does not need to be highly precise (e.g., greater than about 100 μm), the pattern may be formed using a mask with a shape suitable for evaporation or sputtering of the electrode material. In some embodiments, when a coating material, such as an organic conductive compound, can be applied, a wet film formation method, such as a printing method or a coating method, is used. In some embodiments, the anode has a transmittance of greater than 10% when emitted light passes through it, and the anode has a sheet resistance of several hundred ohms per unit area or less. In some embodiments, the anode has a thickness of 10 to 1,000 nm. In some embodiments, the anode has a thickness of 10 to 200 nm. In some embodiments, the thickness of the anode varies depending on the material used.

[0175] cathode: In some embodiments, the cathode is made of an electrode material such as a metal with a low work function (4 eV or less) (referred to as an electron-injecting metal), alloy, conductive compound, or a combination thereof. In some embodiments, the electrode material is selected from sodium, sodium-potassium alloy, magnesium, lithium, magnesium-copper mixture, magnesium-silver mixture, magnesium-aluminum mixture, magnesium-indium mixture, aluminum-aluminum oxide (Al2O3) mixture, indium, lithium-aluminum mixture, and rare earth elements. In some embodiments, a mixture of an electron-injecting metal and a second metal, which is a stable metal having a higher work function than the electron-injecting metal, is used. In some embodiments, the mixture is selected from magnesium-silver mixture, magnesium-aluminum mixture, magnesium-indium mixture, aluminum-aluminum oxide (Al2O3) mixture, lithium-aluminum mixture, and aluminum. In some embodiments, the mixture improves electron-injecting properties and oxidation resistance. In some embodiments, the cathode is fabricated by forming the electrode material as a thin film by evaporation or sputtering. In some embodiments, the cathode has a sheet resistance of several hundred ohms per unit area or less. In some embodiments, the cathode has a thickness of 10 nm to 5 μm. In some embodiments, the cathode has a thickness of 50 to 200 nm. In some embodiments, one of the anode and cathode of the organic electroluminescent device is transparent or semitransparent to transmit emitted light. In some embodiments, a transparent or semitransparent electroluminescent device improves light radiance. In some embodiments, the cathode is formed from a conductive, transparent material as described above for the anode, thereby forming a transparent or semi-transparent cathode. In some embodiments, a device includes an anode and a cathode, both of which are transparent or semi-transparent.

[0176] Injection layer: An injection layer is a layer between an electrode and an organic layer. In some embodiments, the injection layer reduces driving 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 disposed between the anode and the emissive layer or the hole transport layer, and between the cathode and the emissive layer or the electron transport layer. In some embodiments, an injection layer is present. In some embodiments, an injection layer is not present. Preferred examples of compounds that can be used as hole injection materials are listed below.

[0177] [ka]

[0178] Next, preferred examples of compounds that can be used as the electron injection material will be listed. [ka]

[0179] Barrier layer: A blocking layer is a layer that can prevent charges (electrons or holes) and / or excitons present in the light-emitting layer from diffusing outside the light-emitting layer. In some embodiments, an electron blocking layer is present between the light-emitting layer and the hole transport layer and prevents electrons from passing through the light-emitting layer to the hole transport layer. In some embodiments, a hole blocking layer is present between the light-emitting layer and the electron transport layer and prevents holes from passing through the light-emitting layer to the electron transport layer. In some embodiments, a blocking layer prevents excitons from diffusing outside the light-emitting 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 both the functionality of an electron blocking layer and an exciton blocking layer.

[0180] Hole blocking layer: The hole blocking layer functions as an electron transport layer. In some embodiments, the hole blocking layer prevents 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 light-emitting layer. The materials used for the hole blocking layer can be the same materials as those described above for the electron transport layer. Preferred examples of compounds that can be used in the hole blocking layer are listed below.

[0181] [ka]

[0182] Electron barrier layer: The electron blocking layer transports holes. In some embodiments, during hole transport, the electron blocking layer prevents electrons from reaching the hole transport layer. In some embodiments, the electron blocking layer increases the probability of recombination of electrons and holes in the light-emitting layer. The materials used for the electron blocking layer can be the same materials as those described above for the hole transport layer. Specific examples of preferred compounds that can be used as electron blocking materials are listed below.

[0183] [ka]

[0184] Exciton blocking layer: The exciton blocking layer prevents excitons generated through the recombination of holes and electrons in the emissive layer from diffusing to the charge transport layer. In some embodiments, the exciton blocking layer enables effective confinement of excitons in the emissive layer. In some embodiments, the light emission efficiency of the device is improved. In some embodiments, the exciton blocking layer is adjacent to the emissive layer on either the anode side or the cathode side, and on both sides. In some embodiments, when the exciton blocking layer is present on the anode side, it may be present between the hole transport layer and the emissive layer and adjacent to the emissive layer. In some embodiments, when the exciton blocking layer is present on the cathode side, it may be present between the emissive layer and the cathode and adjacent to the emissive layer. In some embodiments, a hole injection layer, an electron blocking layer, or a similar layer is present between the anode and the exciton blocking layer adjacent to the emissive layer on the anode side. In some embodiments, a hole injection layer, an electron blocking layer, a hole blocking layer, or a similar layer is present between the cathode and the 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 excited triplet energy, respectively, of the light-emitting material.

[0185] 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 of hole injection or transport properties and electron blocking properties. 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, pyrazolone 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. 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 hole transport materials are listed below.

[0186] [ka]

[0187] Electron transport layer: The electron transport layer comprises 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 transport material only needs to transport electrons injected from the cathode to the light-emitting layer. In some embodiments, the electron transport material also functions as a hole-blocking material. Examples of electron transport 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, fluorenylidenemethane derivatives, anthraquinodimethanes, anthrone derivatives, oxadiazole 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 polymer material. Specific examples of preferred compounds that can be used as electron transport materials are listed below.

[0188] [ka]

[0189] Furthermore, examples of compounds that can be added to each organic layer are given below, which may be added as a stabilizing material, for example.

[0190] [ka]

[0191] Although specific examples of preferred materials that can be used in organic electroluminescence devices have been given, the materials that can be used in the present invention should not be construed as being limited to the following exemplary compounds. Furthermore, even compounds exemplified as materials having specific functions can be diverted to be used as materials having other functions.

[0192] device: In some embodiments, the light-emitting layer is incorporated into a device, including, but not limited to, an OLED bulb, an OLED lamp, a television display, a computer monitor, a mobile phone, and a tablet. In some embodiments, the electronic device comprises an OLED having an anode, a cathode, and at least one organic layer comprising an emissive layer between the anode and the cathode. In some embodiments, the compositions described herein can be incorporated into various photosensitive or photoactivated devices, such as OLEDs or optoelectronic devices. In some embodiments, the compositions can be useful for facilitating charge or energy transfer within devices and / or as hole transport materials, such as 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), organic solar cells (O-SCs), organic optical detectors, organic photoreceptors, organic field-quench devices (O-FQDs), light-emitting fuel cells (LECs), or organic laser diodes (O-lasers).

[0193] Bulb or Lamp: In some embodiments, the electronic device comprises an OLED comprising an anode, a cathode, and at least one organic layer comprising an emissive 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 a combination of OLEDs. In some embodiments, the combination of OLEDs is a three-color combination (e.g., RGB). In some embodiments, the combination of OLEDs is a combination of colors that are not red, green, or blue (e.g., orange and yellow-green). In some embodiments, the combination of OLEDs is a two-color, four-color, or more-color combination. In some embodiments, the device comprises: a circuit board having a first side with a mounting surface and an opposite second side, the circuit board defining at least one opening; at least one OLED on the mounting surface, the at least one OLED having a light-emitting configuration including an anode, a cathode, and at least one organic layer including a light-emitting layer between the anode and the cathode; a housing for the circuit board; and at least one connector disposed on an end of the housing, the housing and the 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 of the light emitted in a first direction is polarized and emitted in a second direction. In some embodiments, a reflector is used to polarize the light emitted in the first direction.

[0194] Display or Screen: In some embodiments, the light-emitting layer of the present invention can be used in a screen or display. 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, vapor deposition, or chemical vapor deposition (CVD). In some embodiments, the substrate is a photoplate structure useful for two-sided etching to provide pixels with unique aspect ratios. The screen (also called a mask) is used in the manufacturing process of OLED displays. The corresponding artwork pattern design allows for the placement of very steep, narrow tie bars between pixels in the vertical direction and large, 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 onto the TFT backplane. Internal pixel patterning allows for the construction of three-dimensional pixel openings with various aspect ratios in the horizontal and vertical directions. Furthermore, the use of imaged "stripes" or halftone circles within the pixel area protects etching in specific regions until these specific patterns are undercut and removed from the substrate. At that point, all pixel areas are subjected to similar etch rates, but the depth varies depending on the halftone pattern. Varying the size and spacing of the halftone patterns allows for etching with varying degrees of protection within the pixel, enabling the deep, localized etching required to create steep vertical bevels. The preferred material for the deposition mask is Invar, a metal alloy that is cold-rolled into long, thin sheets at steel mills. Invar cannot be electrodeposited onto the spin mandrel as a nickel mask. A suitable, low-cost method for forming open areas in the deposition mask is by wet chemical etching. In some embodiments, the screen or display pattern is a pixel matrix on a substrate. In some embodiments, the screen or display pattern is fabricated using lithography (e.g., photolithography and e-beam lithography). In some embodiments, the screen or display pattern is fabricated using wet chemical etching. In further embodiments, the screen or display pattern is fabricated using plasma etching.

[0195] Device manufacturing method: OLED displays are generally manufactured by forming a large mother panel and then cutting the mother panel into cell panels. Typically, each cell panel on the mother panel is formed by forming a thin film transistor (TFT) having an active layer and source / drain electrodes on a base substrate, applying a planarizing film to the TFT, sequentially forming a pixel electrode, an emissive layer, a counter electrode, and an encapsulation layer, and then cutting the mother panel. OLED displays are generally manufactured by forming a large mother panel and then cutting the mother panel into cell panels. Typically, each cell panel on the mother panel is formed by forming a thin film transistor (TFT) having an active layer and source / drain electrodes on a base substrate, applying a planarizing film to the TFT, sequentially forming a pixel electrode, an emissive layer, a counter electrode, and an encapsulation layer, and then cutting the mother panel.

[0196] In another aspect of the present invention, there is provided a method for manufacturing an organic light emitting diode (OLED) display, the method comprising: forming a barrier layer on a 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 interface between the cell panels. In some embodiments, the barrier layer is an inorganic film, for example, 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 individual cell panels. In some embodiments, the thin film transistor (TFT) layer includes a light-emitting layer, a gate electrode, and source / drain electrodes. Each of the plurality of display units may include 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 organic film applied to the interface is formed of the same material as the planarization film and is formed simultaneously with the planarization film. In some embodiments, the light-emitting unit is connected to the TFT layer by a passivation layer, the planarization 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 either the display unit or the encapsulation layer.

[0197] Each of the organic film and the planarization film may comprise 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 may further include attaching a carrier substrate formed of a glass material to one surface of the base substrate formed of polyimide before forming the barrier layer on the other surface of the base substrate, and separating the carrier substrate from the base substrate before cutting along the interface. In some embodiments, the OLED display is a flexible display. In some embodiments, the passivation layer is an organic film disposed on the TFT layer to cover the TFT layer. In some embodiments, the planarization film is an organic film formed on the passivation layer. In some embodiments, the planarization film is formed of polyimide or acrylic, as is the organic film formed on the edge of the barrier layer. In some embodiments, the planarization 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 directly contacts the base substrate and a remaining portion of the organic film contacts the barrier layer while surrounding the edge of the barrier layer.

[0198] In some embodiments, the light-emitting layer comprises a pixel electrode, a counter electrode, and an organic light-emitting layer disposed between the pixel electrode and the counter electrode, hi some embodiments, the pixel electrode is coupled to a source / drain electrode 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, which causes the organic light-emitting layer to emit light, thereby forming an image. Hereinafter, an image-forming unit having a TFT layer and a light-emitting unit is referred to as a display unit. In some embodiments, the encapsulation layer that covers the display units and prevents penetration of external moisture may be formed into a thin-film encapsulation structure in which organic films and inorganic films are alternately stacked. In some embodiments, the encapsulation layer has a thin-film encapsulation structure in which multiple thin films are stacked. In some embodiments, the organic film applied to the interface portion is disposed at an interval with each of the multiple display units. In some embodiments, the organic film is formed in such a manner that a portion of the organic film directly contacts the base substrate and the remaining portion of the organic film contacts the barrier layer while surrounding the edge of the barrier layer.

[0199] In one embodiment, the OLED display is flexible and uses a flexible base substrate formed of polyimide, hi some embodiments, the base substrate is formed on a carrier substrate formed of a glass material, and the carrier substrate is then 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, while the base substrate is formed on all surfaces of the mother panel, the barrier layer is 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 grooves.

[0200] In some embodiments, the manufacturing method further includes a step of cutting along the interface, in which a groove is formed in the barrier layer and at least a portion of the organic film is formed in the groove, so that the groove does not penetrate the base substrate. In some embodiments, the TFT layer of each cell panel is formed, and a passivation layer (an inorganic film) and a planarization film (an organic film) are disposed on and cover the TFT layer. At the same time as the planarization film (e.g., polyimide or acrylic) is formed, the grooves at the interface are covered with an organic film (e.g., polyimide or acrylic). This prevents cracks from occurring when each cell panel is cut along the grooves at the interface by allowing the organic film to absorb any impacts that may occur. That is, if all barrier layers were completely exposed without the organic film, the impacts would be transmitted to the barrier layers when each cell panel was cut along the grooves at the interface, thereby increasing the risk of cracks. However, in one embodiment, the grooves at the interface between the barrier layers are covered with an organic film to absorb any impacts that would otherwise be transmitted to the barrier layers, allowing each cell panel to be cut softly and preventing cracks from occurring in the barrier layers. In one embodiment, the organic film and the planarizing film covering the groove of the interface portion are spaced apart from each other. For example, if the organic film and the planarizing film are connected to each other as one layer, external moisture may penetrate into the display unit through the planarizing film and the remaining portion of the organic film, so the organic film and the planarizing film are spaced apart from each other so that the organic film is spaced apart from the display unit.

[0201] In some embodiments, the display unit is formed by forming a light-emitting unit, and an encapsulation layer is disposed on the display unit to cover the display unit. Thus, after the mother panel is completely manufactured, the carrier substrate carrying the base substrate is separated from the base substrate. In some embodiments, when a laser beam is irradiated onto the carrier substrate, the carrier substrate is separated from the base substrate due to the difference in thermal expansion coefficient between the carrier substrate and the base substrate. In some embodiments, the mother panel is cut into individual cell panels. In some embodiments, the mother panel is cut along the interface between the cell panels using a cutter. In some embodiments, the grooves at the interface along which the mother panel is cut are covered with an organic film, which absorbs shock during cutting. In some embodiments, this can prevent cracks from occurring in the barrier layer during cutting. In some embodiments, the method reduces product rejection rates and stabilizes product quality. Another embodiment is an OLED display having 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 film applied to the edges of the barrier layer. [Example]

[0202] The following synthesis examples and working examples will further illustrate the features of the present invention. The materials, processing details, processing procedures, etc. shown below can be modified as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the specific examples shown below. The emission characteristics were evaluated using a source meter (Keithley: 2400 series), a semiconductor parameter analyzer (Agilent Technologies: E5273A), an optical power meter (Newport: 1930C), an optical spectrometer (Ocean Optics: USB2000), a spectroradiometer (Topcon: SR-3), and a streak camera (Hamamatsu Photonics K.K.: C4334). In the following synthesis examples, compounds within the general formula (1) were synthesized.

[0203] (Synthesis Example 1) Synthesis of Compound 3a [ka]

[0204] 2-Bromo-8-phenyldibenzofuran (4.83 g, 15.1 mmol), 3-(9H-carbazol-9-yl)phenylboronic acid (5.21 g, 18.2 mmol), tetrakistriphenylphosphinepalladium(0) (1.74 g, 1.51 mmol), and potassium carbonate (6.27 g, 45.4 mmol) were dissolved in a mixture of tetrahydrofuran and water (100 / 50 ml) and stirred at 75°C for 12 hours. The reaction solution was cooled to room temperature, chloroform was added, and the organic layer was washed twice with water, dried over magnesium sulfate, and the solvent was removed. The resulting solid was purified by silica gel column chromatography (eluent: hexane:chloroform = 8:2) to give compound 3a (2.53 g, 34%) as a white solid. 1 H NMR (400MHz, CDCl3,δ): 8.25(s,1H), 8.19-8.16(m,3H), 7.91(s,1H), 7.83-7.63(m,8H), 7.58(d,J=8Hz,1H), 7.54-7.41(m,6H), 7.39-7.29(m,3H). MS(ASAP): 486.25 (M+H + ). Calcd. for C 36 H 23 NO: 485.18.

[0205] (Synthesis Example 2) Synthesis of Compound 3l [ka]

[0206] Under a nitrogen atmosphere, 4-biphenylboronic acid (2.53 g, 12.8 mmol), 2,8-dibromodibenzofuran (5.00 g, 15.3 mmol), tetrakistriphenylphosphinepalladium(0) (0.74 g, 0.640 mmol), and potassium carbonate (3.53 g, 25.6 mmol) were dissolved in a tetrahydrofuran / water (120 / 60 ml) mixture and stirred at 90°C for 16 hours. The reaction solution was cooled to room temperature, chloroform was added, and the organic layer was washed twice with water, dried over magnesium sulfate, and the solvent was removed. The resulting solid was purified by silica gel column chromatography (eluent: hexane:chloroform = 7:3) to give 2-[1,1'-biphenyl]-4-yl-8-bromodibenzofuran as a white solid (3.91 g, 77%). 1 H NMR (400MHz, CDCl3, δ): 8.16-8.13 (m, 2H), 7.79-7.71 (m, 5H), 7.69-7.62 (m, 3H), 7.58 (dd, J = 8.8 Hz, 2.0 Hz, 1H), 7.50-7.46 (m, 3H), 7.38 (t, J = 7.2 Hz, 1H). MS (ASAP): 398.97 (M+H + ). Calcd for C 24 H 15 BrO: 398.03.

[0207] [ka]

[0208] Under a nitrogen atmosphere, 2-[1,1'-biphenyl]-4-yl-8-bromodibenzofuran (2.00 g, 5.01 mmol), 3-(9H-carbazol-9-yl)phenylboronic acid (1.73 g, 6.01 mmol), tetrakistriphenylphosphinepalladium(0) (0.58 g, 0.501 mmol), and potassium carbonate (2.08 g, 15.0 mmol) were dissolved in a tetrahydrofuran / water (60 / 30 mL) mixture and stirred at 75°C for 21 hours. The reaction solution was cooled to room temperature, chloroform was added, and the organic layer was washed twice with water, dried over magnesium sulfate, and the solvent was removed. The resulting solid was purified by silica gel column chromatography (eluent: hexane:chloroform = 7:3). Further recrystallization (toluene / acetonitrile) afforded compound 3l as a white solid (2.05 g, 73%). 1 H NMR (400MHz, CDCl3, δ): 8.27 (d, J = 1.6 Hz, 1H), 8.23 ​​(d, J = 2.0 Hz, 1H), 8.18 (d, J = 7.6 Hz, 2H), 7.92 (t, J = 2.0 Hz, 1H), 7.83-7.75 (m, 5H), 7.73-7.65 (m, 7H), 7.59 (m, 1H), 7.53-7.42 (m, 6H), 7.37 (t, J = 7.6 Hz, 1H), 7.31 (t, J = 8.0 Hz, 2H). MS (ASAP): 562.11 (M+H + ). Calcd for C 42 H 27 NO: 561.21.

[0209] (Synthesis Example 3) Synthesis of Compound 3m [ka]

[0210] Under a nitrogen atmosphere, 2-[1,1'-biphenyl]-3-yl-8-bromodibenzofuran (2.67 g, 6.69 mmol), 3-(9H-carbazol-9-yl)phenylboronic acid (2.31 g, 8.03 mmol), tetrakistriphenylphosphinepalladium(0) (0.77 g, 0.669 mmol), and potassium carbonate (2.77 g, 20.1 mmol) were dissolved in a tetrahydrofuran / water (50 / 25 ml) mixture and stirred at 75 °C for 18 hours. The reaction solution was cooled to room temperature, chloroform was added, and the organic layer was washed twice with water, dried over magnesium sulfate, and the solvent was removed. The resulting solid was purified by silica gel column chromatography (eluent: hexane:chloroform = 7:3) to give compound 3m as a white solid (2.34 g, 63%). 1 H NMR (400MHz, CDCl3, δ): 8.27 (d, J = 1.2 Hz, 1H), 8.24 (d, J = 1.6 Hz, 1H), 8.18 (d, J = 8.0 Hz, 2H), 7.83-7.64 (m, 9H), 7.62-7.41 (m, 9H), 7.38 (t, J = 7.2 Hz, 1H), 7.31 (t, J = 7.2 Hz, 2H). MS (ASAP): 562.24 (M+H + ). Calcd for C 42 H 27 NO: 561.21.

[0211] (Synthesis Example 4) Synthesis of Compound 3p [ka]

[0212] 2-Bromo-2,2'-bis(dibenzofuran) (1.5 g, 3.63 mmol), 3-(9H-carbazol-9-yl)phenylboronic acid (1.15 g, 3.99 mmol), tetrakistriphenylphosphinepalladium(0) (0.209 g, 0.182 mmol), and potassium carbonate (1.51 g, 10.9 mmol) were dissolved in a tetrahydrofuran / water (50 / 25 ml) mixture and stirred at 75°C for 12 hours. The reaction solution was cooled to room temperature, chloroform was added, and the organic layer was washed twice with water, dried over magnesium sulfate, and the solvent was removed. The resulting solid was purified by silica gel column chromatography (eluent: hexane:chloroform = 8:2). The resulting solid was recrystallized (toluene / methanol) to give compound 3p as a white solid (1.23 g, 59%). 1 H NMR (400MHz, CDCl3,δ): 8.29(s,1H), 8.26(s,1H), 8.21(s,1H), 8.18(d,J=8Hz,2H), 8.01(d,J=8Hz,1H), 7.92(s,1H), 7.84-7.58(m,10H), 7.54-7.42(m,5H), 7.38-7.29(m,3H). MS (ASAP): 575.13 (M+H + ). Calcd. for C 42 H 25 NO2: 575.19.

[0213] (Synthesis Example 5) Synthesis of Compound 7m [ka]

[0214] Under a nitrogen atmosphere, 2-[1,1'-biphenyl]-3-yl-8-(3-bromophenyl)dibenzofuran (2.3 g, 4.84 mmol), carbazole-1,2,3,4,5,6,7,8-d8 (0.85 g, 4.84 mmol), tris(dibenzylideneacetone)dipalladium(0) (0.44 g, 0.484 mmol), tri-tert-butylphosphonium tetrafluoroborate (0.28 g, 0.968 mmol), and sodium tert-butoxide (0.93 g, 9.68 mmol) were added to 30 mL of toluene and refluxed for 24 hours. The reaction solution was cooled to room temperature, and chloroform was added. The resulting organic layer was washed twice with water, dried over magnesium sulfate, and the solvent was removed. The resulting solid was purified by silica gel column chromatography (eluent: dichloromethane / n-hexane = 1:1). Further recrystallization (toluene / methanol) gave compound 7m as a white solid (1.47 g, 53°C). 1 H NMR (400MHz, CDCl3, δ): 8.27 (s, 1H), 8.24 (s, 1H), 7.92 (s, 1H), 7.89 (s, 1H), 7.83-7.65 (m, 9H), 7.63-7.55 (m, 3H), 7.47 (t, J = 8 Hz, 2H), 7.39 (t, J = 8 Hz, 1H). MS (ASAP): 570.34 (M+H + ). Calcd for C 42 H 19 D8NO: 569.26.

[0215] Example 1 On a glass substrate with an anode made of indium tin oxide (ITO) with a thickness of 100 nm, the following thin films were deposited by vacuum deposition at a vacuum level of 5.0 × 10 -5 An organic electroluminescence device was fabricated by laminating the layers with Pa. First, HAT-CN was formed to a thickness of 10 nm on ITO, NPD was formed to a thickness of 30 nm on top of that, and EBL1 was formed to a thickness of 10 nm on top of that. Next, a delayed fluorescent material (TADF21) and compound 3a were co-evaporated from separate evaporation sources to form a 40 nm thick layer, which served as the emissive layer. The content of the delayed fluorescent material was 35% by mass, and the content of compound 3a was 65% by mass. Next, SF3-TRZ was formed to a thickness of 10 nm, and then Liq and SF3-TRZ were co-evaporated from separate evaporation sources to form a 30 nm thick layer. The contents of Liq and SF3-TRZ in this layer were 30% by mass and 70% by mass, respectively. Liq was then formed to a thickness of 2 nm, and aluminum (Al) was then evaporated to a thickness of 100 nm to form a cathode, to fabricate an organic electroluminescent device. This device was designated EL device 1. Further, EL device 2 was fabricated using compound 3p instead of compound 3a. Further, a comparative EL device 1 was prepared by using comparative compound 1 in place of compound 3a. Each organic electroluminescence device was fabricated at a current density of 6.3 mA / cm 2 When the devices were made to emit light in an environment of 20°C, all of the devices showed good performance. Next, EL element 1 and comparative EL element 1 were tested at a current density of 6.3 mA / cm in an environment of 100°C. 2 The external quantum efficiency (EQE) and driving voltage were measured after one hour, and EL element 1 showed no change even after one hour, while comparative EL element 1 showed a 1.1% decrease in external quantum efficiency and a 0.22 V increase in driving voltage. Even after the same test was performed in environments at 60°C and 80°C, the external quantum efficiency and driving voltage of EL element 1 showed no change even after one hour. This confirmed that elements using the compound represented by general formula (1) have high thermal stability and maintain stable light-emitting performance even in high-temperature environments.

[0216] Example 2 On a glass substrate with an anode made of indium tin oxide (ITO) with a thickness of 100 nm, the following thin films were deposited by vacuum deposition at a vacuum level of 5.0 × 10 -5An organic electroluminescence device was fabricated by laminating the layers with Pa. First, a 10-nm-thick HAT-CN film was formed on ITO. Then, a 30-nm-thick NPD film was formed on top of that, and a 10-nm-thick TrisPCz film was further formed on top of that. Next, a 40-nm-thick layer was formed by co-evaporation of the luminescent material (G1), the delayed fluorescent material (TADF21), and compound 3l from separate sources. The luminescent material content was 1.4 wt%, the delayed fluorescent material content was 35.0 wt%, and the compound 3l content was 63.6 wt%. Next, a 10-nm-thick layer of SF3-TRZ was formed, followed by co-evaporation of Liq and SF3-TRZ from separate sources to form a 30-nm-thick layer. The Liq and SF3-TRZ contents in this layer were 30 wt% and 70 wt%, respectively. Liq was then formed to a thickness of 2 nm, and aluminum (Al) was then evaporated to a thickness of 100 nm to form a cathode. This device was designated EL device 3. Furthermore, EL devices 4 and 5 were fabricated using compounds 3m and 7m instead of compound 3l. When a current was applied to each of the prepared organic electroluminescence devices, delayed fluorescence originating from the light-emitting material (G1) was observed. 2 The organic electroluminescence devices were driven at 20°C with a current density of 12.6 mA / cm and the external quantum efficiency (EQE) and initial driving voltage were measured. 2 The device was driven at 100 V, and the time (LT95) until the luminous intensity reached 95% of that at the start of driving was measured. The measurement results are shown in Table 2. The EQE and LT95 in Table 2 are shown as relative values ​​when the LT95 of EL device 3 is set to 1, and the driving voltage is shown as a relative value when EL device 3 is set to the reference (0). The measurement results show that even when a host material, a delayed fluorescent material, and a fluorescent material are used in the emitting layer, all devices that use the compound represented by general formula (1) as the host material have high luminous efficiency, low driving voltage, and long device life.

[0217] [Table 2]

[0218] Example 3 On a glass substrate with an anode made of indium tin oxide (ITO) with a thickness of 100 nm, the following thin films were deposited by vacuum deposition at a vacuum level of 5.0 × 10 -5 An organic electroluminescence device was fabricated by laminating the layers with Pa. First, HAT-CN was deposited to a thickness of 10 nm on ITO, followed by a 30 nm layer of NPD. Compound 3l was then deposited to a thickness of 10 nm on top of that. Next, the emissive material (G2), the delayed fluorescent material (TADF72), and comparative compound A were co-deposited from separate deposition sources to form a 40 nm thick layer, which served as the emissive layer. The content of the emissive material was 0.8 wt%, the content of the delayed fluorescent material was 35.0 wt%, and the content of compound 3l was 64.2 wt%. Next, SF3-TRZ was deposited to a thickness of 10 nm, followed by co-depositing Liq and SF3-TRZ from separate deposition sources to form a 30 nm thick layer. The contents of Liq and SF3-TRZ in this layer were 30 wt% and 70 wt%, respectively. Liq was then deposited to a thickness of 2 nm, followed by evaporating aluminum (Al) to a thickness of 100 nm to form a cathode, resulting in the fabrication of an organic electroluminescent device. This device was designated EL device 6. Further, EL device 7 was fabricated using compound 7m instead of compound 3l. When a current was applied to each of the prepared organic electroluminescence devices, delayed fluorescence originating from the luminescent material (G2) was observed. 2 The organic electroluminescence devices were driven at 20°C with a current density of 12.6 mA / cm and the external quantum efficiency (EQE) and initial driving voltage were measured. 2The EL element was driven at 100 V, and the time (LT95) until the luminous intensity reached 95% of that at the start of driving was measured. The measurement results are shown in Table 3. The EQE and LT95 in Table 3 are shown as relative values ​​when the LT95 of EL element 6 is set to 1, and the driving voltage is shown as a relative value when EL element 6 is set to the reference (0). The measurement results show that all elements using the compound represented by general formula (1) as the electron blocking material have high luminous efficiency, low driving voltage, and long device life.

[0219] [Table 3] [ka] [Explanation of symbols]

[0220] 1 Base material 2 Anode 3. Hole injection layer 4. Hole transport layer 5. Light-emitting layer 6 Electron transport layer 7 Cathode

Claims

1. A host material comprising a compound represented by the following general formula (1), for use together with a compound represented by the following general formula (G): 【Chemistry 1】 [In general formula (1), R 1 and R 3 to R 7 each independently represent a hydrogen atom, a deuterium atom, an optionally deuterated alkyl group, or a substituted or unsubstituted aryl group (the aryl group may be a phenyl group which may be fused with an aromatic hydrocarbon ring, an aliphatic hydrocarbon ring, or both), and R 2 is a phenyl group which is substituted with at least a substituted or unsubstituted phenyl group (the phenyl group may be fused with an aromatic hydrocarbon ring, an aliphatic hydrocarbon ring, or both) and which may be further substituted (the phenyl group may be fused with an aromatic hydrocarbon ring, an aliphatic hydrocarbon ring, or both). R 8 to R 19 each independently represent a hydrogen atom, a deuterium atom, or an optionally deuterated alkyl group.] 【Chemistry 2】 [In general formula (G), X １ and X ２ is a nitrogen atom on one side and a boron atom on the other side. １ ~R ２６ , A １ , A ２ R each independently represents a hydrogen atom, a deuterium atom, or a substituent. １ and R ２ , R ２ and R ３ , R ３ and R ４ , R ４ and R ５ , R ５ and R ６ , R ６ and R ７ , R ８ and R ９ , R ９ and R １０ , R １０ and R １１ , R １１ and R １２ , R １３ and R １４ , R １４ and R １５ , R １５ and R １６ , R １６ and R １７ , R １７ and R １８ , R １８ and R １９ , R １９ and R ２０ , R ２０ and R ２１ , R ２１ and R ２２ , R ２２ and R ２３ , R ２３ and R ２４ , R ２４ and R ２５ , R ２５ and R ２６ may be bonded to each other to form a cyclic structure. １ is a nitrogen atom, R １７ and R １８ are bonded to each other to form a single bond to form a pyrrole ring, and X ２ is a nitrogen atom, R ２１ and R ２２ are bonded to each other as a single bond to form a pyrrole ring.

2. A host material for use with a compound represented by general formula (G) according to claim 1, wherein only one pair of R 17 and R 18 , and R 21 and R 22 in general formula (G) are bonded to each other to form a single bond.

3. An electron-blocking material comprising a compound represented by the following general formula (1), which is to be used in combination with a compound represented by the following general formula (G): 【Transformation 3】 [In general formula (1), R 1 and R 3 to R 7 each independently represent a hydrogen atom, a deuterium atom, an optionally deuterated alkyl group, or a substituted or unsubstituted aryl group (the aryl group may be a phenyl group which may be fused with an aromatic hydrocarbon ring, an aliphatic hydrocarbon ring, or both), and R 2 is a phenyl group which is substituted with at least a substituted or unsubstituted phenyl group (the phenyl group may be fused with an aromatic hydrocarbon ring, an aliphatic hydrocarbon ring, or both) and which may be further substituted (the phenyl group may be fused with an aromatic hydrocarbon ring, an aliphatic hydrocarbon ring, or both). R 8 to R 19 each independently represent a hydrogen atom, a deuterium atom, or an optionally deuterated alkyl group.] 【Chemistry 4】 [In general formula (G), X １ and X ２ is a nitrogen atom on one side and a boron atom on the other side. １ ~R ２６ , A １ , A ２ R each independently represents a hydrogen atom, a deuterium atom, or a substituent. １ and R ２ , R ２ and R ３ , R ３ and R ４ , R ４ and R ５ , R ５ and R ６ , R ６ and R ７ , R ８ and R ９ , R ９ and R １０ , R １０ and R １１ , R １１ and R １２ , R １３ and R １４ , R １４ and R １５ , R １５ and R １６ , R １６ and R １７ , R １７ and R １８ , R １８ and R １９ , R １９ and R ２０ , R ２０ and R ２１ , R ２１ and R ２２ , R ２２ and R ２３ , R ２３ and R ２４ , R ２４ and R ２５ , R ２５ and R ２６ may be bonded to each other to form a cyclic structure. １ is a nitrogen atom, R １７ and R １８ are bonded to each other to form a single bond to form a pyrrole ring, and X ２ is a nitrogen atom, R ２１ and R ２２ are bonded to each other as a single bond to form a pyrrole ring.

4. An electron barrier material for use in combination with a compound represented by general formula (G) according to claim 3, wherein only one pair of R 17 and R 18 , and R 21 and R 22 in general formula (G) are bonded to each other to form a single bond.

5. A composition comprising a compound represented by the following general formula (1) and a compound represented by the following general formula (G): 【Transformation 5】 [In general formula (1), R 1 and R 3 to R 7 each independently represent a hydrogen atom, a deuterium atom, an optionally deuterated alkyl group, or a substituted or unsubstituted aryl group (the aryl group may be a phenyl group which may be fused with an aromatic hydrocarbon ring, an aliphatic hydrocarbon ring, or both), and R 2 is a phenyl group which is substituted with at least a substituted or unsubstituted phenyl group (the phenyl group may be fused with an aromatic hydrocarbon ring, an aliphatic hydrocarbon ring, or both) and which may be further substituted (the phenyl group may be fused with an aromatic hydrocarbon ring, an aliphatic hydrocarbon ring, or both). R 8 to R 19 each independently represent a hydrogen atom, a deuterium atom, or an optionally deuterated alkyl group.] 【Transformation 6】 In general formula (G), one of X 1 and X 2 is a nitrogen atom and the other is a boron atom. R 1 to R 26 , A 1 and A 2 each independently represent a hydrogen atom, a deuterium atom or a substituent. R 1 and R 2 , R 2 and R 3 , R 3 and R 4 , R 4 and R 5 , R 5 and R 6 , R 6 and R 7 , R 8 and R 9 , R 9 and R 10 , R 10 and R 11 , R 11 and R 12 , R 13 and R 14 , R 14 and R 15 , R 15 and R 16 , R 16 and R 17 , R 17 and R 18 , R 18 and R 19 , R 19 and R 20 , R 20 and R 21 , R 21 and R 22 , R 22 and R 23 , R 23 and R 24 , R 24 and R 25 , R 25 and R 26 may be bonded to each other to form a cyclic structure, provided that when X 1 is a nitrogen atom, R 17 and R 18 are bonded to each other to form a single bond to form a pyrrole ring, and when X 2 is a nitrogen atom, R 21 and R 22 are bonded to each other to form a single bond to form a pyrrole ring.] 6. The composition according to claim 5, wherein only one pair of R 17 and R 18 , and R 21 and R 22 in general formula (G) are bonded to each other to form a single bond.

7. The composition of claim 5 in the form of a film.

8. The composition of claim 5, further comprising a delayed fluorescent material.

9. The composition according to claim 8 , wherein the delayed fluorescent material is a compound having a cyanobenzene structure in which one cyano group is substituted on a benzene ring.

10. The composition according to claim 8 , wherein the delayed fluorescent material is a compound having a dicyanobenzene structure in which two cyano groups are substituted on a benzene ring.

11. The composition according to claim 8 , wherein the delayed fluorescent material is a compound represented by the following general formula (E): 【Transformation 7】 [In general formula (E), R １ ~R ４ each independently represents a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted ring-fused carbazol-9-yl group. １ ~R ４ At least two of X are substituted ring-fused carbazol-9-yl groups. １ ~X ３ Each independently represents N or C(R), but X １ ~X ３ At least one of Ar is N. R represents a hydrogen atom, a deuterium atom, or a substituent. １ and Ar ２ each independently represents a substituted or unsubstituted aryl group. １ represents a single bond or a divalent linking group.

12. An organic light-emitting device comprising a layer made of the composition according to any one of claims 8 to 11.

13. The organic light-emitting device according to claim 12, wherein the layer consists solely of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms, oxygen atoms, sulfur atoms, boron atoms, and halogen atoms.

14. The organic light-emitting device according to claim 12, which is an organic electroluminescence device.

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