Compound, electronic barrier material, and organic semiconductor element and compound

Abstract

A compound represented by the following general formula is an excellent electronic barrier material. X represents a donor group; R1 to R6 represent substituents; and n1 to n6 represent integers greater than or equal to 0 and less than or equal to the maximum possible number of substitutions.

Description

Compound, electron barrier material, organic semiconductor device and compound

[0001] The present invention relates to a compound useful as an electron blocking material and an organic semiconductor device using the same.

[0002] Research into improving the performance of organic semiconductor devices such as organic electroluminescence devices (organic EL devices) is actively being conducted. For example, to improve the device life and driving voltage of organic electroluminescence devices, it is desirable to improve the functionality of materials involved in charge transport, such as electron transport materials, hole transport materials, electron blocking materials, and hole blocking materials, and development and improvement of these materials is also being promoted. For example, an electron blocking material is a material for the electron blocking layer that is provided between the light-emitting layer and the hole transport layer and functions to prevent electrons present in the light-emitting layer from escaping from the light-emitting layer to the hole transport layer and to transport holes from the hole transport layer to the light-emitting layer. The use of an excellent electron blocking material improves the probability of recombination of electrons and holes in the light-emitting layer, ultimately leading to an extension of the device life. Various compounds have been proposed as electron blocking materials, and for example, Patent Document 1 proposes a compound having the following structure:

[0003]

[0004] WO2010 / 140482

[0005] However, organic electroluminescence devices using the above-mentioned compounds as electron-blocking materials have room for improvement in terms of device life. Therefore, the present inventors have conducted extensive research to provide an electron-blocking material that can extend the device life when used in organic electroluminescence devices.

[0006] As a result of extensive research, the present inventors have found that in a compound having multiple carbazole structures, the function as an electron blocking material can be improved by further condensing a benzofuro structure to the carbazole structure. The present invention has been provided based on this finding, and specifically has the following configuration. [1] A compound represented by the following general formula (1): General formula (1) [In general formula (1), X represents a donor group, R １ ~R ６ each independently represents a deuterium atom or a substituent. n1 and n2 each independently represent an integer of 0 to 4, n3 each independently represent an integer of 0 to 2, n4 and n6 each independently represent an integer of 0 to 3, and n5 each independently represent an integer of 0 to 5. Two adjacent R １ , two adjacent R ２ , two adjacent R ３ , two adjacent R ４ , two adjacent R ５ , two adjacent R ６ may be bonded to each other to form a cyclic structure.] [2] The compound according to [1], which is represented by the following general formula (2A): General formula (2A): [In general formula (2A), R １ ~R ８ each independently represents a deuterium atom or a substituent. n1, n2, n7, and n8 each independently represent an integer from 0 to 4, n3 each independently represent an integer from 0 to 2, n4 and n6 each independently represent an integer from 0 to 3, and n5 each independently represent an integer from 0 to 5. Two adjacent R １ , two adjacent R ２ , two adjacent R ３ , two adjacent R ４ , two adjacent R ５ , two adjacent R ６ , two adjacent R ７ , two adjacent R ８ may be bonded to each other to form a cyclic structure.] [3] The compound according to [1], which is represented by the following general formula (2B): General formula (2B): [In general formula (2B), R １ ~R ９ Each of n1, n2, n8, and n9 independently represents an integer of 0 to 4, each of n3 and n7 independently represents an integer of 0 to 2, each of n4 and n6 independently represents an integer of 0 to 3, and n5 independently represents an integer of 0 to 5. Two adjacent R １ , two adjacent R ２ , two adjacent R ３, two adjacent R ４ , two adjacent R ５ , two adjacent R ６ , two adjacent R ７ , two adjacent R ８ , two adjacent R ９ may be bonded to each other to form a cyclic structure.] [4] The compound according to [1], which is represented by the following general formula (3A): General formula (3A): [In general formula (3A), R １ ~R １１ each independently represents a deuterium atom or a substituent. n1, n4, n6, n7, and n8 each independently represents an integer from 0 to 3, n2 each independently represents an integer from 0 to 4, n3 each independently represents an integer from 0 to 2, and n5, n9, n10, and n11 each independently represents an integer from 0 to 5. Two adjacent R １ , two adjacent R ２ , two adjacent R ３ , two adjacent R ４ , two adjacent R ５ , two adjacent R ６ , two adjacent R ７ , two adjacent R ８ , two adjacent R ９ , two adjacent R １０ , two adjacent R １１ may be bonded to each other to form a cyclic structure.] [5] The compound according to [1], which is represented by the following general formula (3B): General formula (3B): [In general formula (3B), R １ ~R １１ each independently represents a deuterium atom or a substituent. n1, n4, n6, and n8 each independently represent an integer from 0 to 3, n2 and n9 each independently represent an integer from 0 to 4, n3 and n7 each independently represent an integer from 0 to 2, and n5, n10, and n11 each independently represent an integer from 0 to 5. Two adjacent R １ , two adjacent R ２ , two adjacent R ３ , two adjacent R ４ , two adjacent R ５ , two adjacent R ６, two adjacent R ７ , two adjacent R ８ , two adjacent R ９ , two adjacent R １０ , two adjacent R １１ may be bonded to each other to form a cyclic structure.] [6] An electron blocking material comprising the compound according to any one of [1] to [5]. [7] An organic semiconductor device comprising the compound according to any one of [1] to [5]. [8] The organic semiconductor device according to [7], which is an organic electroluminescence device having an anode, a cathode, and at least two organic layers including an emitting layer between the anode and the cathode. [9] The organic semiconductor device according to [8], wherein the emitting layer comprises a host material and a delayed fluorescent material.

[10] The organic semiconductor device according to [8], wherein the emitting layer comprises a host material, a delayed fluorescent material, and a fluorescent material, and the amount of light emitted from the device is greatest from the fluorescent material.

[11] The organic semiconductor device according to any one of [8] to

[10] , which has an organic layer comprising the compound between the anode and the emitting layer.

[12] The organic semiconductor device according to any one of [8] to

[11] , wherein the organic layer comprising the compound is adjacent to the emitting layer.

[13] The organic semiconductor device according to any one of [8] to

[11] , which has a laminated structure in which an organic layer containing the compound, an underlayer, and the light-emitting layer are laminated in this order, and the organic layer containing the compound and the light-emitting layer are not in contact with each other.

[14] The organic semiconductor device according to

[13] , wherein the underlayer contains a host material contained in the light-emitting layer.

[0007] The compound of the present invention is useful as an electron blocking material and can be effectively used in organic semiconductor devices. For example, by using the compound of the present invention in the electron blocking layer of an organic electroluminescence device, the device life can be extended.

[0008] FIG. 2 is a schematic cross-sectional view showing an example of a layer structure of an organic electroluminescence element.

[0009] The present invention will be described in detail below. The following description of the constituent elements may be based on typical embodiments and specific examples of the present invention, but the present invention is not limited to such embodiments and specific examples. In this specification, a numerical range expressed using "to" means a range including the numerical values ​​before and after "to" as the lower and upper limits. In addition, some or all of the hydrogen atoms present in the molecules of the compound used in the present invention may be replaced with deuterium atoms ( ２ In the chemical structural formulas herein, hydrogen atoms are represented by H or are omitted. For example, when the representation of an atom bonded to a carbon atom constituting the ring skeleton of a benzene ring is omitted, H is assumed to be bonded to the carbon atom constituting the ring skeleton at the omitted location. In this specification, the term "substituent" refers to an atom or atomic group other than a hydrogen atom or a deuterium atom. On the other hand, the term "substituted or unsubstituted" means that a hydrogen atom may be substituted with a deuterium atom or a substituent.

[0010] [Compound Represented by General Formula (1)] The compound of the present invention is a compound represented by the following general formula (1).

[0011] General formula (1)

[0012] In general formula (1), X represents a donor group. The donor group here is a group with a negative Hammett σp value. The "Hammett σp value" was proposed by L. P. Hammett and quantifies the influence of a substituent on the reaction rate or equilibrium of a para-substituted benzene derivative. Specifically, it is the constant (σp) specific to the substituent in the para-substituted benzene derivative, which holds between the substituent and the reaction rate constant or equilibrium constant: log(k / k0) = ρσp or log(K / K0) = ρσp. In the above equation, k0 represents the rate constant of the benzene derivative without a substituent, k represents the rate constant of the benzene derivative substituted with a substituent, K0 represents the equilibrium constant of the benzene derivative without a substituent, K represents the equilibrium constant of the benzene derivative substituted with a substituent, and ρ represents a reaction constant determined by the type and conditions of the reaction. For an explanation of the "Hammett σp value" and the numerical values ​​of each substituent in the present invention, reference can be made to the description of the σp value in Hansch, C. et al., Chem. Rev., 91, 165-195 (1991). Groups with a positive Hammett σp value tend to exhibit electron-withdrawing (acceptor) properties. In one embodiment of the present invention, the compound represented by general formula (1) does not contain a substituent with a σp value of 0.2 or more.

[0013] The donor group is preferably a group containing a substituted amino group. The substituent bonded to the nitrogen atom of the amino group is preferably a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group, more preferably a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group, and even more preferably a substituted or unsubstituted aryl group. The substituted amino group is particularly preferably a substituted or unsubstituted diarylamino group or a substituted or unsubstituted diheteroarylamino group. The two atomic groups bonded to the nitrogen atom of the substituted amino group may be bonded to each other to form a cyclic structure. The donor group in the present invention may be a group bonded via the nitrogen atom of the substituted amino group, or may be a group bonded via a group to which the substituted amino group is bonded. The group to which the substituted amino group is bonded is preferably a π-conjugated group. More preferred are groups bonding via the nitrogen atom of a substituted amino group, or groups bonding via the benzene ring to which the nitrogen atom of a substituted amino group is bonded, and even more preferred are groups bonding via the nitrogen atom of a substituted amino group. A particularly preferred donor group in the present invention is a substituted or unsubstituted carbazol-9-yl group. A benzene ring or a heterocycle may be further fused to the carbazol-9-yl group. The substituent of the carbazol-9-yl group may be, for example, a substituent selected from the following substituent group a, a substituent selected from the following substituent group b, a substituent selected from the following substituent group c, or a substituent selected from the following substituent group d. Furthermore, the two benzene rings constituting the carbazol-9-yl group may each independently be fused with another ring. The fused ring may be any of an aromatic ring, a heteroaromatic ring, an aliphatic hydrocarbon ring, and an aliphatic heterocycle, or may be a ring formed by further condensing any of these. Preferably, the aromatic ring is an aromatic ring, a heteroaromatic ring, or a condensed ring thereof. An example of an aromatic ring is a benzene ring. The heteroaromatic ring refers to a ring that exhibits aromaticity and 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 adopted.In one embodiment of the present invention, a furan ring, a thiophene ring, a pyrrole ring, or a pyridine ring can be used as the heteroaromatic ring. In one embodiment of the present invention, the cyclic structure is a benzene ring, which may be substituted with a substituent selected from any one of the following substituent groups a to d, and may be fused with one or more other cyclic structures such as a benzene ring or a furan ring. The benzene ring may be unsubstituted. In one embodiment of the present invention, the cyclic structure is a furan ring, which may be substituted with a substituent selected from any one of the following substituent groups a to d, and may be fused with one or more other cyclic structures such as a benzene ring or a furan ring. Preferred examples of the carbazol-9-yl group include an unsubstituted carbazol-9-yl group, a carbazol-9-yl group substituted at at least one of the 3- and 6-positions, and a carbazol-9-yl group substituted at both the 3- and 6-positions. The donor group which can be represented by X preferably has 13 or more atoms other than hydrogen atoms and deuterium atoms, and can be selected, for example, from the range of 13 to 40, or from the range of 13 to 26. The donor group which can be represented by X can be composed only of atoms selected from, for example, hydrogen atoms, deuterium atoms, carbon atoms, nitrogen atoms, and oxygen atoms, or can be composed only of atoms selected from, for example, hydrogen atoms, deuterium atoms, carbon atoms, and nitrogen atoms, or can be composed only of atoms selected from, for example, hydrogen atoms, carbon atoms, and nitrogen atoms.

[0014] Specific examples of donor groups that can be used for X are given below, but the donor groups that can be used for X are not limited to these specific examples. ３ For example, D4 ​​represents a 3,6-dimethylcarbazol-9-yl group. D represents a deuterium atom.

[0015] In general formula (1), R １ ~R ６are atoms or atomic groups that can substitute for hydrogen atoms bonded to the benzene ring, and specifically, each independently represents a deuterium atom or a substituent. When n1 to n6 are integers of 2 or more, multiple R １ ~R ６ may be the same or different. １ is R ２ ~R ６ may be the same as or different from R ２ ~R ６ The same is true for R １ ~R ６ may each be a deuterium atom, and R １ ~R ６ Each of R may be a substituent. １ ~R ６ may be, for example, a substituent selected from the following substituent group a, a substituent selected from the following substituent group b, a substituent selected from the following substituent group c, or a substituent selected from the following substituent group d. １ ~R ６ is one group selected from the group consisting of alkyl groups and aryl groups, or a group in which two or more groups are combined. In one embodiment of the present invention, it is an aryl group which may be substituted with one group selected from the group consisting of alkyl groups and aryl groups, or a group in which two or more groups are combined. For example, R １ ~R ６ is a phenyl or naphthyl group, and for example, a phenyl group may be selected. １ ~R ６ Specific examples of the substituents that can be taken by R are as follows: １ ~R ６ The substituents that can be adopted as the methyl group are not to be construed as being limited by these specific examples. ３ For example, N8 represents a 4-methylphenyl group, and D represents a deuterium atom.

[0016]

[0017] In the general formula (1), n1 to n6 are 0 or more, and R １ ~R ６ represents any integer up to the maximum number of substitutions that can be bonded. That is, n1 and n2 each independently represent an integer from 0 to 4, n3 an integer from 0 to 2, n4 and n6 each independently represent an integer from 0 to 3, and n5 an integer from 0 to 5. In one aspect of the present invention, n1 is 0. In one aspect of the present invention, n1 is 1. In one aspect of the present invention, n2 is 0. In one aspect of the present invention, n2 is 1 or 2. In one aspect of the present invention, n5 is 0. In one aspect of the present invention, n5 is 1. In one aspect of the present invention, n3, n4, and n6 are 0. In one aspect of the present invention, n1 to n6 each independently represent an integer from 0 to 2. In one aspect of the present invention, n1 to n6 each independently represent 0 or 1. In one aspect of the present invention, n1 to n6 are 0. In one aspect of the present invention, the sum of n1 to n6 is any one of 0 to 10, and may be any one of 0 to 6, any one of 0 to 4, or any one of 0 to 2, for example, 1 or 2.

[0018] In general formula (1), two adjacent R １ , two adjacent R ２ , two adjacent R ３ , two adjacent R ４ , two adjacent R ５ , two adjacent R ６ may be bonded to each other to form a cyclic structure. The cyclic structure may be any of an aromatic ring, a heteroaromatic ring, an aliphatic hydrocarbon ring, and an aliphatic heterocyclic ring, or may be a ring formed by condensing these. For details and preferred ranges of the aromatic ring, the heteroaromatic ring, the aliphatic hydrocarbon ring, and the aliphatic heterocyclic ring, the description of the ring condensed to the two benzene rings constituting the carbazol-9-yl group above can be referred to. In one embodiment of the present invention, two adjacent R １ are not bonded to each other and do not form a ring structure. In one embodiment of the present invention, two adjacent R ２ are not bonded to each other and do not form a ring structure. In one embodiment of the present invention, two adjacent R ３are not bonded to each other and do not form a ring structure. In one embodiment of the present invention, two adjacent R ４ are not bonded to each other and do not form a ring structure. In one embodiment of the present invention, two adjacent R ５ are not bonded to each other and do not form a ring structure. In one embodiment of the present invention, two adjacent R ６ are not bonded to each other and do not form a ring structure. In one embodiment of the present invention, two adjacent R １ , two adjacent R ２ , two adjacent R ３ , two adjacent R ４ , two adjacent R ５ , two adjacent R ６ are not bonded to each other and do not form a cyclic structure. ２ ) ｎ２ The benzofuro structure containing the benzene ring to which is attached (R ３ ) ｎ３The benzofuro structure may be fused in any position and orientation relative to the benzene ring to which it is bonded. As the benzofuran-fused carbazol-9-yl group formed by condensation of the benzofuro structure, a substituted or unsubstituted benzofuro[2,3-a]carbazol-9-yl group can be used (Partial Structure 1). A substituted or unsubstituted benzofuro[3,2-a]carbazol-9-yl group can also be used (Partial Structure 2). A substituted or unsubstituted benzofuro[2,3-b]carbazol-9-yl group can also be used (Partial Structure 3). A substituted or unsubstituted benzofuro[3,2-b]carbazol-9-yl group can also be used (Partial Structure 4). A substituted or unsubstituted benzofuro[2,3-c]carbazol-9-yl group can also be used (Partial Structure 5). A substituted or unsubstituted benzofuro[3,2-c]carbazol-9-yl group can also be used (Partial Structure 6). In one embodiment of the present invention, either Partial Structure 1 or Partial Structure 2 is selected. In one aspect of the present invention, either substructure 3 or substructure 4 is selected. In one aspect of the present invention, either substructure 5 or substructure 6 is selected. In one aspect of the present invention, either substructure 1, substructure 3 or substructure 5 is selected. In one aspect of the present invention, either substructure 2, substructure 4 or substructure 6 is selected.

[0019] In one embodiment of the present invention, the compound represented by general formula (1) has two or three carbazole structures in the molecule. For example, the number may be two, or may be three. In one embodiment of the present invention, the compound represented by general formula (1) has one or two dibenzofuran structures in the molecule. For example, the number may be one, or may be two. In one embodiment of the present invention, the compound represented by general formula (1) has three carbazole structures and one or two dibenzofuran structures in the molecule. In this case, the number of dibenzofuran structures may be, for example, one, or may be two. In this case, it is preferable that one benzene ring of the dibenzofuran structure is one benzene ring of the carbazole structure. In one embodiment of the present invention, the compound represented by general formula (1) does not have a pyrrole ring that does not constitute a carbazole structure. In one embodiment of the present invention, the compound represented by general formula (1) does not have a furan ring that does not constitute a dibenzofuran structure. In one embodiment of the present invention, the compound represented by general formula (1) does not have a thiophene ring, an indene ring, or a silaindene ring. In one embodiment of the present invention, the compound represented by general formula (1) does not contain any heterocycle other than the heterocycles constituting the carbazole structure and the dibenzofuran structure, and does not contain any fused rings having six or more fused rings.

[0020] As the compound represented by general formula (1), for example, a compound represented by general formula (2A) can be selected.

[0021] In general formula (2A), R １ ~R ８ each independently represents a deuterium atom or a substituent. n1, n2, n7, and n8 each independently represent an integer from 0 to 4, n3 each independently represent an integer from 0 to 2, n4 and n6 each independently represent an integer from 0 to 3, and n5 each independently represent an integer from 0 to 5. Two adjacent R １ , two adjacent R ２ , two adjacent R ３ , two adjacent R ４ , two adjacent R ５ , two adjacent R ６, two adjacent R ７ , two adjacent R ８ may be bonded to each other to form a cyclic structure. １ ~R ６ For details of n1 to n6, please refer to the corresponding descriptions in general formula (1). ７ and R ８ For details, see R in general formula (1). １ For details of n7 and n8, the description of n1 in general formula (1) can be referred to. In one embodiment of the present invention, n7 and n8 are integers of 0 to 2, and for example, n7 and n8 may be 0, n7 and n8 may be 1, or n7 and n8 may be 2.

[0022] As the compound represented by general formula (1), for example, a compound represented by general formula (2B) can be selected.

[0023] In general formula (2B), R １ ~R ９ Each of n1, n2, n8, and n9 independently represents an integer of 0 to 4, each of n3 and n7 independently represents an integer of 0 to 2, each of n4 and n6 independently represents an integer of 0 to 3, and n5 independently represents an integer of 0 to 5. Two adjacent R １ , two adjacent R ２ , two adjacent R ３ , two adjacent R ４ , two adjacent R ５ , two adjacent R ６ , two adjacent R ７ , two adjacent R ８ , two adjacent R ９ may be bonded to each other to form a cyclic structure. １ ~R ６ For details of n1 to n6, please refer to the corresponding descriptions in general formula (1). ７ , R ８ , R ９For details, see R in general formula (1) in order. ３ , R １ , R ２ For details of n7, n8, and n9, the descriptions of n3, n1, and n2 in general formula (1) can be referred to. In one embodiment of the present invention, n7 to n9 are, for example, any integer of 0 to 2, and for example, n7 to n9 may be 0 or 1, and for example, n7 to n9 may be 0.

[0024] As the compound represented by general formula (1), for example, a compound represented by general formula (3A) can be selected.

[0025] In general formula (3A), R １ ~R １１ each independently represents a deuterium atom or a substituent. n1, n4, n6, n7, and n8 each independently represents an integer from 0 to 3, n2 each independently represents an integer from 0 to 4, n3 each independently represents an integer from 0 to 2, and n5, n9, n10, and n11 each independently represents an integer from 0 to 5. Two adjacent R １ , two adjacent R ２ , two adjacent R ３ , two adjacent R ４ , two adjacent R ５ , two adjacent R ６ , two adjacent R ７ , two adjacent R ８ , two adjacent R ９ , two adjacent R １０ , two adjacent R １１ may be bonded to each other to form a cyclic structure. １ ~R ６ For details of n2 to n6, please refer to the corresponding descriptions in general formula (1). ７ , R ８ For details, see R in general formula (1). １ The description of R ９ , R １０ , R １１ For details, see R in general formula (1) in order. ５n1, n7, and n8 may be any integer from 0 to 2, for example, n1, n7, and n8 may be 0 or 1, for example, n1, n7, and n8 may be 0. n5, and n9 to n11 may be any integer from 0 to 2, for example, n5, n9 to n11 may be 0 or 1, for example, n5, n9 to n11 may be 0.

[0026] As the compound represented by general formula (1), for example, a compound represented by general formula (3B) can be selected.

[0027] In general formula (3B), R １ ~R １１ each independently represents a deuterium atom or a substituent. n1, n4, n6, and n8 each independently represent an integer from 0 to 3, n2 and n9 each independently represent an integer from 0 to 4, n3 and n7 each independently represent an integer from 0 to 2, and n5, n10, and n11 each independently represent an integer from 0 to 5. Two adjacent R １ , two adjacent R ２ , two adjacent R ３ , two adjacent R ４ , two adjacent R ５ , two adjacent R ６ , two adjacent R ７ , two adjacent R ８ , two adjacent R ９ , two adjacent R １０ , two adjacent R １１ may be bonded to each other to form a cyclic structure. １ ~R ６ For details of n2 to n6, please refer to the corresponding descriptions in general formula (1). ７ , R ８ , R ９ For details, see R in general formula (1) in order. ３ , R １ , R ２ The description of R １０ , R １１ For details, see R in general formula (1) in order. ５n7 and n8 may be any integer from 0 to 2, for example, n7 and n8 may be 0 or 1, for example, n7 and n8 may be 0. n9 to n11 may be any integer from 0 to 2, for example, n9 to n11 may be 0 or 1, for example, n9 to n11 may be 0.

[0028] The compound represented by general formula (1) preferably has, for example, any of the ring skeletons shown below. At least one hydrogen atom in the skeleton shown below may be substituted with a deuterium atom or a substituent, and the skeleton shown below may further have a ring fused thereto. Note that the skeleton may not further have a ring fused thereto. For details of the substituent, see the above R １ ~R １１ The explanation of the substituents in the description of the above can be referred to.

[0029] Specific examples of the compound represented by general formula (1) are shown below. However, the compounds represented by general formula (1) that can be used in the present invention should not be construed as being limited by these specific examples. In the following specific examples, Ph represents a phenyl group.

[0030] Compounds 1a to 12g above in which all hydrogen atoms present in the molecule have been substituted with deuterium atoms are disclosed herein as compounds 1a(D) to 12g(D), respectively.

[0031] In one embodiment of the present invention, a compound having an axisymmetric structure is selected as the compound represented by general formula (1). In another embodiment of the present invention, a compound having an asymmetric structure is selected as the compound represented by general formula (1).

[0032] The molecular weight of the compound represented by general formula (1) is preferably 1500 or less, more preferably 1200 or less, even more preferably 1000 or less, and even more preferably 900 or less, when it is intended to use an organic layer containing the compound represented by general formula (1) as a film formed by a vapor deposition method. The lower limit of the molecular weight is the molecular weight of the smallest compound in the group of compounds represented by general formula (1). The compound represented by general formula (1) may be formed into a film by a coating method regardless of its molecular weight. Using a coating method, it is possible to form a film even from compounds with relatively large molecular weights. The compound represented by general formula (1) has the advantage of being easily soluble in organic solvents. Therefore, the compound represented by general formula (1) is easy to apply a coating method to and is also easy to purify to increase its purity.

[0033] The compound represented by general formula (1) preferably does not contain a metal atom or a boron atom. For example, the compound represented by general formula (1) may be a compound consisting of atoms selected from the group consisting of carbon, hydrogen, deuterium, nitrogen, oxygen, and sulfur atoms. For example, the compound represented by general formula (1) may be a compound consisting of atoms selected from the group consisting of carbon, hydrogen, deuterium, nitrogen, and oxygen atoms. For example, the compound represented by general formula (1) may be a compound consisting of atoms selected from the group consisting of carbon, hydrogen, nitrogen, and oxygen atoms.

[0034] In the present specification, the term "substituent group a" refers to 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 heteroaryl ... It means one group or a combination of two or more groups selected from the group consisting of a heteroarylthio group (for example, having 5 to 30 atoms constituting the ring skeleton), an acyl group (for example, having 1 to 40 carbon atoms), an alkenyl group (for example, having 1 to 40 carbon atoms), an alkynyl group (for example, having 1 to 40 carbon atoms), an alkoxycarbonyl group (for example, having 1 to 40 carbon atoms), an aryloxycarbonyl group (for example, having 1 to 40 carbon atoms), a heteroaryloxycarbonyl group (for example, having 1 to 40 carbon atoms), a silyl group (for example, a trialkylsilyl group having 1 to 40 carbon atoms), and a nitro group. In this specification, "substituent group b" refers to one group or a combination of two or more selected from the group consisting of alkyl groups (e.g., 1 to 40 carbon atoms), alkoxy groups (e.g., 1 to 40 carbon atoms), aryl groups (e.g., 6 to 30 carbon atoms), aryloxy groups (e.g., 6 to 30 carbon atoms), heteroaryl groups (e.g., 5 to 30 ring atoms), heteroaryloxy groups (e.g., 5 to 30 ring atoms), and diarylamino groups (e.g., 0 to 20 carbon atoms). In this specification, "substituent group c" refers to one group or a combination of two or more selected from the group consisting of alkyl groups (e.g., 1 to 20 carbon atoms), aryl groups (e.g., 6 to 22 carbon atoms), heteroaryl groups (e.g., 5 to 20 ring atoms), and diarylamino groups (e.g., 12 to 20 carbon atoms). As used herein, the term "substituent group d" refers to one group or a combination of two or more groups selected from the group consisting of 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).In the present specification, when a "substituent" or "substituted or unsubstituted" is used, the substituent may be selected from, for example, substituent group a, substituent group b, substituent group c, or substituent group d.

[0035] In this specification, the term "alkyl group" may be linear, branched, or cyclic. Furthermore, two or more of the linear, cyclic, and branched moieties may be mixed. 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, an isohexyl group, a 2-ethylhexyl group, an n-heptyl group, an isoheptyl group, an n-octyl group, an isooctyl group, an n-nonyl group, an isononyl group, an n-decanyl group, an isodecanyl group, a cyclopentyl group, a cyclohexyl group, and a cycloheptyl group. The alkyl group serving as a substituent may be further substituted with an aryl group. An "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 have 30 or less, 20 or less, 10 or less, 6 or less, or 4 or less carbon atoms. Specific examples of alkenyl groups include ethenyl, n-propenyl, isopropenyl, n-butenyl, isobutenyl, n-pentenyl, isopentenyl, n-hexenyl, isohexenyl, and 2-ethylhexenyl. The alkenyl group may be further substituted with a substituent. An "aryl group" or a "heteroaryl group" may be a monocyclic 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 may 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, and these may be condensed rings.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 number of atoms constituting the ring skeleton of the aryl group is preferably 6 to 40, more preferably 6 to 20, and may be selected from the range of 6 to 14, or may be selected from the range of 6 to 10. The number of atoms constituting the ring skeleton of the heteroaryl group is preferably 4 to 40, more preferably 5 to 20, and may be selected from the range of 5 to 14, or may be selected from the range of 5 to 10.

[0036] [Organic Semiconductor Device] The compound represented by general formula (1) can be preferably applied to an organic semiconductor device. For example, a CMOS (complementary metal oxide semiconductor) can be fabricated using the compound represented by general formula (1). In an embodiment of the present disclosure, an organic optical device such as an organic electroluminescence device or a solid-state imaging device (e.g., a CMOS image sensor) can be fabricated using the compound represented by general formula (1). In particular, the compound represented by general formula (1) of the present invention can be used in an organic light-emitting device such as an organic electroluminescence device (organic EL device). In particular, the compound represented by general formula (1) of the present invention can be effectively used as an electron-blocking material for an organic light-emitting device. In particular, the use of the compound represented by general formula (1) of the present invention in an electron-blocking layer can extend the device life.

[0037] An organic electroluminescent device has a structure including at least an anode, a cathode, and an organic layer formed between the anode and the cathode. The organic layer includes at least an emitting layer, and preferably includes one or more organic layers (particularly an electron blocking layer) in addition to the emitting layer. Examples of organic layers constituting an organic electroluminescent device 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, an exciton blocking layer, and an underlayer for the emitting layer. The hole transport layer may be a hole injection transport layer having a hole injection function, and the electron transport layer may be an electron injection transport layer having an electron injection function. A specific structural example of an organic electroluminescent device is shown in FIG. 1. In FIG. 1, 1 represents a substrate, 2 represents an anode, 3 represents a hole injection layer, 4 represents a hole transport layer, 5 represents an electron blocking layer, 6 represents an underlayer, 7 represents a emitting layer, 8 represents a hole blocking layer, 9 represents an electron transport layer, 10 represents an electron injection layer, and 11 represents a cathode. Each component and each layer of the organic electroluminescent element will be described below. The description of the substrate and the light-emitting layer also applies to the substrate and the light-emitting layer of the organic photoluminescent element.

[0038] (Electron Blocking Layer) In a preferred embodiment of the present invention, the compound represented by general formula (1) is used in the electron blocking layer of an organic electroluminescent device. The electron blocking layer may contain only the compound represented by general formula (1), or may also contain compounds other than the compound represented by general formula (1). The concentration of the compound represented by general formula (1) in the electron blocking layer is preferably 50% by weight or more, more preferably 90% by weight or more, for example, 99% by weight or more, or even 99.9% by weight or more. The thickness of the electron blocking layer is preferably 1 nm or more, more preferably 3 nm or more, and can be, for example, 5 nm or more, or, for example, 10 nm or more. The thickness of the electron blocking layer is preferably less than 30 nm, more preferably less than 20 nm, and can be, for example, 15 nm or less. The thickness of the electron blocking layer is preferably smaller than the thickness of the light-emitting layer. The thickness of the electron blocking layer is preferably half or less, more preferably one-third or less, and can be, for example, one-quarter or less, of the thickness of the light-emitting layer. Furthermore, it is preferably 1 / 20 or more, and can be, for example, 1 / 10 or more, or 1 / 6 or more. The electron blocking layer containing the compound represented by general formula (1) is preferably provided between the light-emitting layer and the anode. In one embodiment of the present invention, the light-emitting layer and the electron blocking layer are stacked so as to be in direct contact with each other. In one embodiment of the present invention, the present invention includes a stacked structure in which, from the anode side, an electron blocking layer containing the compound represented by general formula (1), an underlayer, and a light-emitting layer are stacked in this order. The electron blocking layer and the underlayer are stacked so as to be in direct contact with each other, and the underlayer and the light-emitting layer are stacked so as to be in direct contact with each other, but the electron blocking layer and the light-emitting layer are not in contact with each other.

[0039] (Underlayer) The underlayer is formed for purposes such as improving the alignment of the light-emitting layer, and is a layer containing a hole-transporting material. In one embodiment of the present invention, the underlayer contains a compound having a common partial structure with the compound contained in the light-emitting layer. The common partial structure here means that the compound has a common partial structure consisting of 12 or more atoms other than hydrogen atoms and deuterium atoms. Preferably, the compound has a common partial structure consisting of 16 or more atoms other than hydrogen atoms and deuterium atoms. For example, the compound may have a common partial structure consisting of 20 or more atoms other than hydrogen atoms and deuterium atoms. In one embodiment of the present invention, the underlayer contains the same compound as the compound contained in the light-emitting layer. In one embodiment of the present invention, the underlayer contains only the same compound as the compound contained in the light-emitting layer. In one embodiment of the present invention, the underlayer contains the same compound as the host material contained in the light-emitting layer. The thickness of the underlayer is preferably 1 nm or more, more preferably 3 nm or more, and can be, for example, 5 nm or more. The thickness of the adjacent layer is preferably less than 30 nm, more preferably less than 20 nm, and can be, for example, 10 nm or less, or 7 nm or less. The thickness of the underlayer is preferably smaller than that of the light-emitting layer. The thickness of the underlayer is preferably equal to or less than half of the thickness of the light-emitting layer, more preferably equal to or less than one-third, and can be, for example, equal to or less than one-quarter. Also, it is preferably equal to or more than one-twentieth, and can be, for example, equal to or more than one-tenth. The thickness of the underlayer is preferably smaller than that of the electron blocking layer. The thickness of the underlayer can be, for example, equal to or less than three-quarters, for example, equal to or less than two-thirds, or for example, equal to or less than one-half of the thickness of the electron blocking layer. Also, it is preferably equal to or more than one-twentieth, and can be, for example, equal to or more than one-tenth, or for example, equal to or more than one-quarter.

[0040] (Light-emitting layer) The light-emitting layer emits light after excitons are generated by the recombination of holes and electrons injected from the anode and cathode, respectively. The light-emitting layer contains at least a light-emitting material. In order for an organic electroluminescent device to achieve high light-emitting efficiency, it is important to confine the singlet and triplet excitons of the light-emitting material within the light-emitting material. Therefore, it is preferable to use a host material in addition to the light-emitting material in the light-emitting layer. As the host material, an organic compound having a higher excited singlet energy than the light-emitting material of the present invention can be used, and it is preferable to use an organic compound having a higher excited singlet energy and a higher excited triplet energy than the light-emitting material. The use of a host material makes it possible to confine the singlet and triplet excitons generated in the light-emitting material within the molecules of the light-emitting material, thereby fully utilizing its light-emitting efficiency. However, high light-emitting efficiency may be achieved even if singlet and triplet excitons cannot be sufficiently confined. Therefore, any host material that can achieve high light-emitting efficiency can be used in the present invention without any particular restrictions. In the organic electroluminescence device of the present invention, the maximum amount of light emitted from the device is light emitted from the light-emitting material contained in the light-emitting layer. This light emission includes fluorescent light and may also include delayed fluorescence. However, light emission from the host material may be present in part or in part of the light emission. When a host material is used, the concentration of the light-emitting material in the light-emitting layer is preferably 0.1 wt % or more, more preferably 1 wt % or more, and preferably 50 wt % or less, more preferably 20 wt % or less, and even more preferably 10 wt % or less.

[0041] An assist dopant may be used in the emitting layer. In this case, the emitting layer is composed of a host material, an assist dopant, and an emitting material. Here, the host material has a higher lowest excited singlet energy level than the assist dopant, and the emitting material has a lower lowest excited singlet energy level than the assist dopant. In the present invention, it is particularly preferable to use a delayed fluorescent material as the assist dopant. Delayed fluorescence is fluorescence emitted when an excited compound undergoes reverse intersystem crossing from an excited triplet state to an excited singlet state and then returns to the ground state from that excited singlet state. This fluorescence is observed later than the fluorescence (prompt fluorescence) from the excited singlet state resulting from a direct transition from the ground state. In the present invention, when the luminescence transient decay curve of a thin film containing the target compound is measured at 300 K, if a luminescent component with a long luminescence lifetime (delayed fluorescence) is observed in addition to a luminescent component with a short luminescence lifetime (prompt fluorescence), the target compound is considered to be a delayed fluorescent material. The delayed fluorescent material is preferably a thermally activated delayed fluorescent material capable of undergoing reverse intersystem crossing upon absorption of thermal energy. The thermal activation of a delayed fluorescent material can be confirmed by the fact that the luminescence lifetime, determined by measuring the luminescence transient decay curve, increases depending on the measurement temperature. By using a delayed fluorescent material as an assist dopant, the energy of the excited singlet state generated by direct transition from the ground state in the assist dopant and the excited singlet energy due to reverse intersystem crossing are efficiently transferred to the luminescent material, thereby effectively assisting the luminescence of the luminescent material. When the luminescent layer is composed of a host material, an assist dopant, and a luminescent material, the concentration of the assist dopant in the luminescent layer is preferably lower than the content of the host material. Specifically, when the total weight of the content of the host material, the content of the assist dopant, and the content of the luminescent material is taken as 100% by weight, the content of the host material is preferably 15% by weight or more and 99.9% by weight or less, the content of the assist dopant is preferably 5.0% by weight or more and 50% by weight or less, and the content of the luminescent material is preferably 0.5% by weight or more and 5.0% by weight or less. In one embodiment of the present invention, the light-emitting layer does not contain an inorganic compound or a metal atom.In one embodiment of the present invention, no phosphorescence is observed from the light-emitting layer at 300K.

[0042] The host material used in the light-emitting layer is preferably an organic compound that has hole-transporting and electron-transporting capabilities, prevents the emission wavelength from shifting to longer wavelengths, and has a high glass transition temperature. In one embodiment of the present invention, a compound containing a carbazole structure can be preferably selected as the host material. In a preferred embodiment of the present invention, the host material contains two or more structures selected from the group consisting of a carbazole structure, a dibenzofuran structure, and a dibenzothiophene structure. For example, a compound containing two structures or a compound containing three structures can be selected. In a preferred embodiment of the present invention, the host material can be selected as a compound containing a 1,3-phenylene structure. In a preferred embodiment of the present invention, the host material can be selected as a compound containing a biphenylene structure. In a preferred embodiment of the present invention, the host material can be selected as a compound containing 5 to 8 benzene rings in the molecule. For example, a compound containing 5, 6, or 7 benzene rings can be selected. Preferred compounds that can be used as the host material are listed below, but the host materials that can be employed in the present invention should not be construed as being limited by the specific examples below.

[0043] In the light-emitting layer, a delayed fluorescent material can be used as the light-emitting material or the assist dopant. Different delayed fluorescent materials can be used as the light-emitting material and the assist dopant. When the emission lifetime is measured using a fluorescence lifetime measurement system (such as a streak camera system manufactured by Hamamatsu Photonics), fluorescence with an emission lifetime of 100 ns (nanoseconds) or more is usually observed. The delayed fluorescent material has a difference ΔE between the lowest excited singlet energy and the lowest excited triplet energy at 77 K. ＳＴis 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. 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.

[0044] In the present invention, the lowest excited singlet energy (E Ｓ１ ) and the lowest excited triplet energy (E Ｔ１ ) is a value determined by the following procedure. ＳＴ is E Ｓ１ -E Ｔ１ (1) The lowest excited singlet energy (E Ｓ１ ) Thin film or toluene solution of the compound to be measured (concentration 10 －５ A sample is prepared by preparing a solution of 1000 mol / L. The fluorescence spectrum of this sample is measured at room temperature (300K). The fluorescence spectrum has the vertical axis representing emission and the horizontal axis representing wavelength. 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 determined. This wavelength value is converted to an energy value using the following conversion formula, and the value is called E Ｓ１ Conversion formula: E Ｓ１ [eV] = 1239.85 / λedge. The emission spectra in the examples described below were measured using an LED light source (Thorlabs, M300L4) as the excitation light source and a detector (Hamamatsu Photonics, PMA-12 multichannel spectrometer C10027-01). (2) Lowest excited triplet energy (E Ｔ１ ) lowest excited singlet energy (E Ｓ１The 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 on 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 determined. This wavelength value is converted to an energy value using the following conversion formula, and the value E Ｔ１ Conversion formula: E Ｔ１ [eV] = 1239.85 / λedge A 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 among the spectral maxima, consider a 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 maximum is defined as the tangent to the rising edge of the phosphorescence spectrum on the short wavelength side. Note that maximum points having peak intensities that are 10% or less of the maximum peak intensity of the spectrum are not included in the shortest wavelength maximum, and the tangent drawn at the point where the slope is maximum and is closest to the shortest wavelength maximum is defined as the tangent to the rising edge of the phosphorescence spectrum on the short wavelength side.

[0045] It is preferable that the delayed fluorescent material does not contain metal atoms. For example, a compound consisting of atoms selected from the group consisting of carbon atoms, hydrogen atoms, deuterium atoms, nitrogen atoms, oxygen atoms, and sulfur atoms can be selected as the delayed fluorescent material. For example, a compound consisting of carbon atoms, hydrogen atoms, and nitrogen atoms may be selected as the delayed fluorescent material. Typical delayed fluorescent materials include compounds having a structure in which one to two acceptor groups and at least one donor group are bonded to a benzene ring. Preferred examples of the acceptor group include groups containing a heteroaryl ring containing a nitrogen atom as a ring skeleton-constituting atom, such as a cyano group or a triazinyl ring. Preferred examples of the donor group include a substituted or unsubstituted carbazol-9-yl group. Examples of such compounds include a compound in which three or more substituted or unsubstituted carbazol-9-yl groups are bonded to the benzene ring, and a compound in which each of the five-membered ring moieties of a substituted or unsubstituted benzofuran ring, a substituted or unsubstituted benzothiophene ring, a substituted or unsubstituted indole ring, a substituted or unsubstituted indene ring, or a substituted or unsubstituted silaindene ring is condensed to at least one of the two benzene rings constituting the carbazol-9-yl group.

[0046] As the delayed fluorescent material, a compound that is represented by the following general formula (4) and emits delayed fluorescence can be preferably used. General formula (4)

[0047] In the general formula (4), X １ ~X ５ represents N or C—R. R represents a hydrogen atom, a deuterium atom, or a substituent. X １ ~X ５ When two or more of X represent C—R, those C—R may be the same or different from each other. １ ~X ５ At least one of X is CD (where D represents a donor group). １ ~X ５When all of the above are C—R, Z represents an acceptor group. Among the compounds represented by general formula (4), particularly preferred compounds are compounds represented by the following general formula (5):

[0048] In the general formula (5), X １ ~X ５ represents N or C—R. R represents a hydrogen atom, a deuterium atom, or a substituent. X １ ~X ５ When two or more of X represent C—R, those C—R may be the same or different from each other. １ ~X ５ In a preferred embodiment of the present invention, at least one of X is CD (where D represents a donor group). １ ~X ５ is not C—CN. That is, it is a compound having a structure in which one cyano group and at least one donor group are bonded to a benzene ring. In another preferred embodiment of the present invention, X ２ Only represents C-CN, and X １ , X ３ ~X ５ is not C—CN. That is, it is a compound having a structure in which at least one donor group is bonded to the benzene ring of isophthalonitrile. In another embodiment of the present invention, X ３ Only represents C-CN, and X １ , X ２ , X ４ , X ５ is not C—CN. That is, it is a compound having a structure in which at least one donor group is bonded to the benzene ring of terephthalonitrile.

[0049] In the general formula (4) and the general formula (5), X １ ~X ５ represents N or C-R, but at least one is CD. １ ~X ５ The number of N is 0 to 4, for example, X １ and X ３ and X ５ , X １ and X ３ , X １and X ４ , X ２ and X ３ , X １ and X ５ , X ２ and X ４ , X １ Only, X ２ Only, X ３ An example can be given where only X is N. １ ~X ５ The number of CDs is 1 to 5, preferably 2 to 5. For example, X １ and X ２ and X ３ and X ４ and X ５ , X １ and X ２ and X ４ and X ５ , X １ and X ２ and X ３ and X ４ , X １ and X ３ and X ４ and X ５ , X １ and X ３ and X ５ , X １ and X ２ and X ５ , X １ and X ２ and X ４ , X １ and X ３ and X ４ , X １ and X ３ , X １ and X ４ , X ２ and X ３ , X １ and X ５ , X ２ and X ４ , X １ Only, X ２ Only, X ３ An example is when only X is CD. １ ~X ５ At least one of the groups may be CA, where A represents an acceptor group. １ ~X ５The number of CA is preferably 0 to 2, and more preferably 0 or 1. Preferred examples of A in CA include a cyano group and a heterocyclic aromatic group having an unsaturated nitrogen atom. １ ~X ５ may each independently be CD or CA. １ ~X ５ When two adjacent R's represent C-R, the two R's may 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 be formed.

[0050] The donor group D in the general formula (4) and the general formula (5) is preferably a group represented by the following general formula (6):

[0051] In general formula (6), R ３１ and R ３２ R each independently represents a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group. ３１ and R ３２may bond to each other to form a cyclic structure. L represents a single bond, a substituted or unsubstituted arylene group, or a substituted or unsubstituted heteroarylene group. The substituent that can be introduced into the arylene group or heteroarylene group of L may be a group containing a structure represented by general formula (4) or general formula (5), or may be a group represented by general formulas (7) to (9) described below. These groups may be introduced up to the maximum number of substituents that can be introduced into L. Furthermore, when multiple substituents are introduced, these substituents may be the same or different. * represents the bonding position to the carbon atom (C) that constitutes the ring skeleton of the ring in general formula (4) or general formula (5). The substituent means a monovalent group that can substitute for a hydrogen atom, and can be selected, for example, from Substituent Group A described below, Substituent Group B described below, Substituent Group C described below, or Substituent Group D described below.

[0052] The compound represented by general formula (6) is preferably a compound represented by any one of the following general formulas (7) to (9): General formula (7) General formula (8) General formula (9)

[0053] In the general formulas (7) to (9), R ５１ ~R ６０ , R ６１ ~R ６８ , R ７１ ~R ７８ R each independently represents a hydrogen atom, a deuterium atom, or a substituent. For the explanation and preferred range of the substituent here, please refer to the explanation and preferred range of the substituent in general formula (10) described later. ５１ ~R ６０ , R ６１ ~R ６８ , R ７１ ~R ７８are each preferably independently a group represented by any one of the above general formulas (7) to (9). The number of substituents in general formulas (7) to (9) is not particularly limited. It is also preferable that all are unsubstituted (i.e., hydrogen atoms or deuterium atoms). Furthermore, when there are two or more substituents in each of general formulas (7) to (9), these substituents may be the same or different. When a substituent is present in general formulas (7) to (9), the substituent is R ５２ ~R ５９ In the case of general formula (8), R ６２ ~R ６７ In the case of general formula (9), R ７２ ~R ７７ It is preferable that either of the above is used.

[0054] In general formula (9), X represents a divalent oxygen atom, sulfur atom, substituted or unsubstituted nitrogen atom, substituted or unsubstituted carbon atom, substituted or unsubstituted silicon atom, carbonyl group, or a divalent substituted or unsubstituted ethylene group, substituted or unsubstituted vinylene group, substituted or unsubstituted o-arylene group, or substituted or unsubstituted o-heteroarylene group, each of which has a linking chain length of 1 atom. The substituent can be selected, for example, from Substituent Group A described below, Substituent Group B described below, Substituent Group C described below, or Substituent Group D described below.

[0055] In the general formulas (7) to (9), L １２ ~L １４ represents a single bond, a substituted or unsubstituted arylene group, or a substituted or unsubstituted heteroarylene group. １２ ~L １４ For the description and preferred range of the arylene group or heteroarylene group represented by, reference can be made to the description and preferred range of the arylene group or heteroarylene group represented by L. １２ ~L １４is preferably a single bond or a substituted or unsubstituted arylene group. The substituent of the arylene group or heteroarylene group may be a group represented by any one of the general formulae (7) to (9). The groups represented by the general formulae (7) to (9) are １１ ~L １４ The maximum number of substituents that can be introduced into the ring may be introduced. When a plurality of groups represented by general formulas (7) to (9) are introduced, the substituents may be the same or different. * indicates the bonding position to the carbon atom (C) that constitutes the ring skeleton of the ring in general formula (4) or general formula (5).

[0056] In the general formulas (7) to (9), R ５１ and R ５２ , R ５２ and R ５３ , R ５３ and R ５４ , R ５４ and R ５５ , R ５５ and R ５６ , R ５６ and R ５７ , R ５７ and R ５８ , R ５８ and R ５９ , R ５９ and R ６０ , R ６１ and R ６２ , R ６２ and R ６３ , R ６３ and R ６４ , R ６５ and R ６６ , R ６６ and R ６７ , R ６７ and R ６８ , R ７１ and R ７２ , R ７２ and R ７３ , R ７３ and R ７４ , R ７５ and R ７６ , R ７６ and R ７７ , R ７７ and R ７８may be bonded to each other to form a cyclic structure. For details and preferred examples of the cyclic structure, see X in the above general formula (4) and general formula (5). １ ~X ５ The description of the cyclic structure and preferred examples thereof can be referred to.

[0057] Among the cyclic structures, preferred are structures in which a substituted or unsubstituted benzofuran ring, a substituted or unsubstituted benzothiophene ring, a substituted or unsubstituted indole ring, a substituted or unsubstituted indene ring, or a substituted or unsubstituted silaindene ring is fused to at least one benzene ring of general formulas (7) to (9). More preferred are groups represented by the following general formulas (8a) to (8f) fused to general formula (8).

[0058] In the general formulae (8a) to (8f), L １１ and L ２１ ~L ２６ represents a single bond or a divalent linking group. １１ and L ２１ ~L ２６ For the description and preferred range of L ２ In general formulas (8a) to (8f), R ４１ ~R １１０ 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 ４８ , R ５１ and R ５２ , R ５２ and R ５３ , R ５３ and R ５４ , R ５４ and R ５５ , R ５５ and R ５６ , R ５６ and R５７ , R ５７ and R ５８ , R ５８ and R ５９ , R ５９ and R ６０ , R ６１ and R ６２ , R ６２ and R ６３ , R ６３ and R ６４ , R ６５ and R ６６ , R ６６ and R ６７ , R ６７ and R ６８ , R ６８ and R ６９ , R ６９ and R ７０ , R ７２ and R ７３ , R ７３ and R ７４ , R ７４ and R ７５ , R ７５ and R ７６ , R ７６ and R ７７ , R ７７ and R ７８ , R ７８ and R ７９ , R ７９ and R ８０ , R ８１ and R ８２ , R ８２ and R ８３ , R ８３ and R ８４ , R ８４ and R ８５ , R ８６ and R ８７ , R ８７ and R ８８ , R ８８ and R ８９ , R ８９ and R ９０ , R ９１ and R ９２ , R ９３ and R ９４ , R ９４ and R ９５ , R ９５ and R ９６ , R ９６ and R ９７ , R ９７ and R ９８, R ９９ and R １００ , R １０１ and R １０２ , R １０２ and R １０３ , R １０３ and R １０４ , R １０４ and R １０５ , R １０５ and R １０６ , R １０７ and R １０８ , R １０８ and R １０９ , R １０９ and R １１０ may 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 be formed. The number of rings contained in the group represented by general formula (9) may be selected from the range of 3 to 5, or may be selected from the range of 5 to 7. The number of rings contained in the groups represented by general formulas (8a) to (8f) may be selected from the range of 5 to 7, or may be 5. R ４１ ~R １１０ The substituents that R may take may be selected from the following substituent group B, the following substituent group C, or the following substituent group D. Preferably, R is 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, R４１ ~R １１０ 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 １１０ is a hydrogen atom or an unsubstituted aryl group having 6 to 10 carbon atoms. ４１ ~R １１０ are all hydrogen atoms. ４１ ~R １１０ The carbon atoms to which C—R is bonded (carbon atoms constituting the ring skeleton) may each independently be substituted with a nitrogen atom. ４１ ~C-R １１０ may each independently be substituted with N. The number of nitrogen atoms substituted is preferably 0 to 4, more preferably 1 to 2, among the groups represented by general formulas (8a) to (8f). In one embodiment of the present invention, the number of nitrogen atoms substituted is 0. Furthermore, when two or more groups are substituted with nitrogen atoms, the number of nitrogen atoms substituted in one ring is preferably 1. In general formulas (8a) to (8f), X １ ~X ６ represents an oxygen atom, a sulfur atom or N—R. In one embodiment of the present invention, X １ ~X ６ is an oxygen atom. In one aspect of the present invention, X １ ~X ６ is a sulfur atom. In one aspect of the present invention, X １ ~X ６ is N-R. R represents a hydrogen atom or a substituent, and is preferably a substituent. As the substituent, a group from the following substituent group A, a group from the following substituent group B, a group from the following substituent group C, or a group from the following substituent group D can be selected. For example, an unsubstituted phenyl group or a phenyl group substituted with one group or a combination of two or more groups selected from the group consisting of alkyl groups and aryl groups can be preferably used. In general formulas (8a) to (8f), * represents a bonding position.

[0059] In the present invention, a compound represented by the following general formula (10) that emits delayed fluorescence can be particularly preferably used as a delayed fluorescent material. In a preferred embodiment of the present invention, a compound represented by general formula (10) can be used as a delayed fluorescent material. General formula (10)

[0060] In general formula (10), R １ ~R ５ 0 to 4 represent a cyano group, and R １ ~R ５ At least one of R represents a substituted amino group, and the remaining R １ ~R ５ represents a hydrogen atom, a deuterium atom, or a substituent other than a cyano group and a substituted amino group. The substituted amino group here is preferably a substituted or unsubstituted diarylamino group, and the two aryl groups constituting the substituted or unsubstituted diarylamino group may be linked to each other. The linkage may be by a single bond (in which case a carbazole ring is formed), or by -O-, -S-, -N(R ６ ) -, -C(R ７ ) (R ８ ) -, -Si(R ９ ) (R １０ )- or other linking groups. ６ ~R １０ represents a hydrogen atom, a deuterium atom or a substituent, R ７ and R ８ , R ９ and R １０ may be linked to each other to form a cyclic structure. １ ~R ５ For example, R １ and R ２ , R １ and R ３ , R １ and R ４ , R １ and R ５ , R ２ and R ３ , R ２ and R ４ , R １ and R ２ and R ３ , R１ and R ２ and R ４ , R １ and R ２ and R ５ , R １ and R ３ and R ４ , R １ and R ３ and R ５ , R ２ and R ３ and R ４ , R １ and R ２ and R ３ and R ４ , R １ and R ２ and R ３ and R ５ , R １ and R ２ and R ４ and R ５ , R １ and R ２ and R ３ and R ４ and R ５ can be a substituted amino group. A cyano group can also be １ ~R ５ For example, R １ , R ２ , R ３ , R １ and R ２ , R １ and R ３ , R １ and R ４ , R １ and R ５ , R ２ and R ３ , R ２ and R ４ , R １ and R ２ and R ３ , R １ and R ２ and R ４ , R １ and R ２ and R ５ , R １ and R ３ and R ４ , R １ and R ３ and R ５ , R２ and R ３ and R ４ can be a cyano group. R that is neither a cyano group nor a substituted amino group can be １ ~R ５ represents a hydrogen atom, a deuterium atom, or a substituent. Examples of the substituent referred to here include the following substituent group A. Preferred examples of the substituent when the aryl group of the diarylamino group is substituted also include the substituents of the following substituent group A, and further include a cyano group and a substituted amino group. Instead of substituent group A, it is also possible to select from substituent group B, substituent group C, or substituent group D. For specific examples of the compounds and compounds encompassed by the general formula (10), reference can be made to paragraphs 0008 to 0048 of WO2013 / 154064, paragraphs 0009 to 0030 of WO2015 / 080183, paragraphs 0006 to 0019 of WO2015 / 129715, paragraphs 0013 to 0025 of JP-A-2017-119663, and paragraphs 0013 to 0026 of JP-A-2017-119664, all of which are cited herein as part of this specification.

[0061] In addition, a compound represented by the following general formula (11) that emits delayed fluorescence can also be particularly preferably used as the delayed fluorescence material of the present invention. In a preferred embodiment of the present invention, a compound represented by general formula (11) can be used as the delayed fluorescence material. General formula (11)

[0062] In the general formula (11), Y １ , Y ２ and Y ３ two of which represent nitrogen atoms and the remaining one represents a methine group, or Y １ , Y ２ and Y ３ All of the above represent nitrogen atoms. １ and Z ２ R each independently represents a hydrogen atom, a deuterium atom, or a substituent. １１ ~R １８ each independently represents a hydrogen atom, a deuterium atom, or a substituent; R １１ ~R １８At least one of the arylamino group and the carbazolyl group is preferably a substituted or unsubstituted arylamino group or a substituted or unsubstituted carbazolyl group. １１ ~R １８ may form a single bond or a linking group together with Z. The compound represented by general formula (11) contains at least two carbazole structures in the molecule. １ , Z ２ The substituents that R can take can be selected from, for example, the following substituent group A, the following substituent group B, the following substituent group C, or the following substituent group D. １１ ~R １８ Specific examples of the substituents that the arylamino group and carbazolyl group may have include the substituents in the following substituent group A, a cyano group, a substituted arylamino group, and a substituted alkylamino group. １１ and R １２ , R １２ and R １３ , R １３ and R １４ , R １５ and R １６ , R １６ and R １７ , R １７ and R １８ may be bonded to each other to form a cyclic structure. Among the compounds represented by general formula (11), the compound represented by general formula (12) is particularly useful.

[0063] In the general formula (12), Y １ , Y ２ and Y ３ two of which represent nitrogen atoms and the remaining one represents a methine group, or Y １ , Y ２ and Y ３ All of the above represent nitrogen atoms. ２ represents a hydrogen atom, a deuterium atom or a substituent. １１ ~R １８ and R ２１ ~R ２８R each independently represents a hydrogen atom, a deuterium atom, or a substituent. １１ ~R １８ and / or R ２１ ~R ２８ It is preferable that at least one of the arylamino group and the carbazolyl group is a substituted or unsubstituted arylamino group or a substituted or unsubstituted carbazolyl group. １１ ~R １８ or R ２１ ~R ２８ may be taken together with Z to form a single bond or a linking group. ２ Examples of the substituent that R may take include the substituents of the following substituent group A, the substituents of the following substituent group B, the substituents of the following substituent group C, and the substituents of the following substituent group D. １１ ~R １８ , R ２１ ~R ２８ Specific examples of the substituents that the arylamino group and carbazolyl group may have include the substituents in the following substituent group A, a cyano group, a substituted arylamino group, and a substituted alkylamino group. １１ and R １２ , R １２ and R １３ , R １３ and R １４ , R １５ and R １６ , R １６ and R １７ , R １７ and R １８ , R ２１ and R ２２ , R ２２ and R ２３ , R ２３ and R ２４ , R ２５ and R ２６ , R ２６ and R ２７ , R ２７ and R ２８may be bonded to each other to form a cyclic structure. For specific examples of the compounds included in general formula (12), reference can be made to paragraphs 0020 to 0062 of WO 2013 / 081088, which are incorporated herein by reference, and the compounds described in Appl. Phys. Lett., 98, 083302 (2011).

[0064] Furthermore, a compound that is represented by the following general formula (13) and emits delayed fluorescence can also be particularly preferably used as the delayed fluorescence material of the present invention.

[0065] In general formula (13), R ９１ ~R ９６ each independently represents a hydrogen atom, a deuterium atom, a donor group, or an acceptor group, at least one of which is the donor group and at least two of which are the acceptor groups. The substitution positions of the at least two acceptor groups are not particularly limited, but it is preferable that the compound contains two acceptor groups that are in a meta-position relationship with respect to each other. For example, R ９１ is a donor group, at least R ９２ and R ９４ is an acceptor group, or at least R ９２ and R ９６ A preferred example is a structure in which the acceptor group is represented by the formula (13). The acceptor groups present in the molecule may all be the same or different from one another, but it is possible to select a structure in which all are the same. The number of acceptor groups is preferably 2 to 3, and for example, 2 can be selected. Two or more donor groups may be present, and in that case, the donor groups may all be the same or different from one another. The number of donor groups is preferably 1 to 3, and may be, for example, one or two. For the explanation and preferred ranges of the donor group and the acceptor group, refer to the corresponding explanation and preferred ranges for general formula (4). In particular, in general formula (13), the donor group is preferably represented by general formula (6), and the acceptor group is preferably a cyano group or the following general formula (14). General formula (14)

[0066] In the general formula (14), Y ４ ~Y ６ represents a nitrogen atom or a methine group, at least one of which is a nitrogen atom, and preferably all of which are nitrogen atoms. １０１ ~R １１０ Each of L independently represents a hydrogen atom, a deuterium atom, or a substituent, and at least one of them is preferably an alkyl group. For the explanation and preferred range of the substituents, please refer to the explanation and preferred range of the substituents in the general formula (10) above. １５ represents a single bond or a linking group, and the description and preferred range of L in the general formula (6) can be referred to. In a preferred embodiment of the present invention, L in the general formula (14) １５ * represents the bonding position to the carbon atom (C) constituting the ring skeleton of the ring in general formula (13).

[0067] Preferred compounds that can be used as delayed fluorescent materials are listed below: In the structural formulas of the following exemplary compounds, t-Bu represents a tertiary butyl group (tert-butyl group).

[0068] As the delayed fluorescent material, other known delayed fluorescent materials can be used in appropriate combination. Even unknown delayed fluorescent materials can be used. Examples of delayed fluorescent materials include those described in 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, and 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 WO 2013 / 133359 A, paragraphs 0008 to 0032 of WO 2013 / 161437 A JP-A-2014-9352, paragraphs 0007 to 0041 and 0060 to 0069, JP-A-2014-9224, paragraphs 0008 to 0048 and 0067 to 0076, JP-A-2017-119663, paragraphs 0013 to 0025, JP-A-2017-119664, paragraphs 0013 to 0026, JP-A-2017- JP-A-2017-226838, paragraphs 0010 to 0050, JP-A-2018-100411, paragraphs 0012 to 0043, and WO 2018 / 047853, paragraphs 0016 to 0044. Compounds encompassed by the general formulas described in paragraphs 0012 to 0025, particularly exemplary compounds, which emit delayed fluorescence can be mentioned.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.

[0069] When a delayed fluorescent material is used as an assist dopant in the light-emitting layer, a compound having a lower minimum excited singlet energy than the assist dopant is used as the light-emitting material. Examples of light-emitting materials used in combination with the assist dopant include compounds having a multiple resonance effect of boron atoms and nitrogen atoms, and compounds containing a fused aromatic ring structure such as anthracene, pyrene, and perylene. The delayed fluorescent materials exemplified above can also be used. In a preferred embodiment of the present invention, a compound represented by the following general formula (15) is used as the light-emitting material used in combination with the assist dopant. General formula (15)

[0070] In the above general formula (15), Ar １~Ar ３ are each independently an aryl ring or a heteroaryl ring, and at least one hydrogen atom in these rings may be substituted, or the rings may be fused. When a hydrogen atom is substituted, it is preferably substituted with one group or a combination of two or more groups selected from the group consisting of a deuterium atom, an aryl group, a heteroaryl group, and an alkyl group. When the rings are fused, it is preferably fused with a benzene ring or a heteroaromatic ring (for example, a furan ring, a thiophene ring, a pyrrole ring, etc.). R ａ and R ａ R' each independently represents a substituent, and is preferably one group or a combination of two or more groups selected from the group consisting of a deuterium atom, an aryl group, a heteroaryl group, and an alkyl group. ａ and Ar １ , Ar １ and Ar ２ , Ar ２ and R ａ ', R ａ ' and Ar ３ , Ar ３ and R ａ may be bonded to each other to form a cyclic structure.

[0071] The compound represented by the general formula (15) preferably contains at least one carbazole structure. For example, one of the benzene rings constituting the carbazole structure is Ar １ and one of the benzene rings constituting the carbazole structure may be represented by Ar ２ and one of the benzene rings constituting the carbazole structure may be represented by Ar ３ In addition, Ar may be a ring represented by the formula: １ ~Ar ３ A carbazolyl group may be bonded to one or more of the following. For example, Ar ３ A substituted or unsubstituted carbazol-9-yl group may be bonded to the ring represented by the formula:

[0072] Ar １ ~Ar ３ Ar may have a fused aromatic ring structure such as anthracene, pyrene, or perylene bonded thereto.１ ~Ar ３ The ring represented by R may be one of the rings constituting a fused aromatic ring structure. ａ and R ａ At least one of the groups may be a group having a fused aromatic ring structure.

[0073] A compound may contain a plurality of skeletons represented by general formula (15). For example, the skeletons represented by general formula (15) may be bonded to each other via a single bond or a linking group. The skeleton represented by general formula (15) may further include a structure exhibiting a multiple resonance effect in which benzene rings are linked to each other via a boron atom, a nitrogen atom, an oxygen atom, or a sulfur atom.

[0074] In a preferred embodiment of the present invention, a compound containing a BODIPY (4,4-difluoro-4-bora-3a,4a-diaza-s-indacene) structure is used as the light-emitting material used in combination with the assist dopant. For example, a compound represented by the following general formula (16) is used.

[0075] In general formula (16), R １ ~R ７ are each independently a hydrogen atom, a deuterium atom, or a substituent. １ ~R ７ At least one of the above is preferably a group represented by the following general formula (17): In general formula (17), R １１ ~R １５ Each independently represents a hydrogen atom, a deuterium atom or a substituent, and * represents a bonding position. １ ~R ７ In a preferred embodiment of the present invention, the number of R １ ~R ７ In a preferred embodiment of the present invention, at least one of R １ , R３ , R ５ , R ７ is a group represented by general formula (17). In a preferred embodiment of the present invention, R １ , R ３ , R ４ , R ５ , R ７ In a preferred embodiment of the present invention, only R １ , R ３ , R ４ , R ５ , R ７ is a group represented by general formula (17), and R ２ and R ４ is a hydrogen atom, a deuterium atom, an unsubstituted alkyl group (e.g., having 1 to 10 carbon atoms), or an unsubstituted aryl group (e.g., having 6 to 14 carbon atoms). １ ~R ７ In a preferred embodiment of the present invention, all of R １ and R ７ In a preferred embodiment of the present invention, R ３ and R ５ In a preferred embodiment of the present invention, R ２ and R ６ In a preferred embodiment of the present invention, R １ and R ７ are identical, and R ３ and R ５ are the same and R １ and R ３ In a preferred embodiment of the present invention, R １ , R ３ , R ５ , R ７ In a preferred embodiment of the present invention, R １ and R ４ and R ７ are identical, and R ３ or R ５ In a preferred embodiment of the present invention, R ３ and R ４ and R ５ are identical, and R １ or R ７In a preferred embodiment of the present invention, R １ , R ３ , R ５ , R ７ are all R ４ is different.

[0076] R in general formula (17) １１ ~R １５ The substituents that may be taken by may be selected, for example, from the following Substituent Group A, from the following Substituent Group B, from the following Substituent Group C, or from the following Substituent Group D. When a substituted amino group is selected as the substituent, a di-substituted amino group is preferred, and the two substituents on the amino group are preferably each independently a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, or a substituted or unsubstituted alkyl group, and a substituted or unsubstituted aryl group (a diarylamino group) is particularly preferred. The substituents that may be taken by the two aryl groups of the diarylamino group may be selected, for example, from the following Substituent Group A, from the following Substituent Group B, from the following Substituent Group C, or from the following Substituent Group D. The two aryl groups of the diarylamino group may be bonded to each other via a single bond or a linking group, and the linking group referred to here is represented by R ３３ and R ３４ The explanation of the linking group in the above formula (9) can be referred to. A specific example of the diarylamino group is a substituted or unsubstituted carbazol-9-yl group. Examples of the substituted or unsubstituted carbazol-9-yl group include L １１ In a preferred embodiment of the present invention, R in general formula (17) is a single bond. １３ is the only substituent, and R １１ , R １２ , R １４ , R １５ In a preferred embodiment of the present invention, R in general formula (17) is a hydrogen atom. １１ is the only substituent, and R １２ , R １３ , R １４ , R １５In a preferred embodiment of the present invention, R in general formula (17) is a hydrogen atom. １１ and R １３ is the only substituent, and R １２ , R １４ , R １５ is a hydrogen atom. １ ~R ７ Among these, R of general formula (17) １１ ~R １５ may contain a group in which all of R are hydrogen atoms (i.e., a phenyl group). ２ , R ４ , R ６ may be a phenyl group.

[0077] In general formula (16), R ８ and R ９ are each independently one group or a combination of two or more groups selected from the group consisting of a hydrogen atom, a deuterium atom, a halogen atom, an alkyl group (e.g., having 1 to 40 carbon atoms), an alkoxy group (e.g., having 1 to 40 carbon atoms), an aryloxy group (e.g., having 6 to 30 carbon atoms), and a cyano group. In a preferred embodiment of the present invention, R ８ and R ９ In a preferred embodiment of the present invention, R ８ and R ９ is a halogen atom, and is particularly preferably a fluorine atom.

[0078] In one embodiment of the present invention, R １ ~R ９ The total number of substituted or unsubstituted alkoxy groups, substituted or unsubstituted aryloxy groups, and substituted or unsubstituted amino groups present in R in general formula (16) is preferably 3 or more, and for example, a compound having 3 or 4 groups can be used. １ ~R ７ The total number of substituted or unsubstituted alkoxy groups, substituted or unsubstituted aryloxy groups, and substituted or unsubstituted amino groups present in R is preferably three or more, and for example, a compound having three or four groups may be employed.８ and R ９ In general formula (16), R may not have an alkoxy group, an aryloxy group, or an amino group. １ , R ３ , R ４ , R ５ , R ７ The total number of substituted or unsubstituted alkoxy groups, substituted or unsubstituted aryloxy groups, and substituted or unsubstituted amino groups present in R is preferably three or more, and for example, a compound having three or four groups may be employed. ２ , R ６ , R ８ , R ９ In a preferred embodiment of the present invention, R has three or more substituted or unsubstituted alkoxy groups. In a preferred embodiment of the present invention, R has four or more substituted or unsubstituted alkoxy groups. In a preferred embodiment of the present invention, R has one or more substituted or unsubstituted alkoxy groups and two or more substituted or unsubstituted aryloxy groups. In a preferred embodiment of the present invention, R has two or more substituted or unsubstituted alkoxy groups and one or more substituted or unsubstituted amino groups. In a preferred embodiment of the present invention, R １ , R ４ , R ７ In a preferred embodiment of the present invention, R １ , R ４ , R ７ Each of these groups contains a substituted or unsubstituted alkoxy group.

[0079] In one embodiment of the present invention, R １ ~R ９The total number of substituents present in R in general formula (16) having a Hammett σp value of less than -0.2 is three or more. Examples of substituents having a Hammett σp value of less than -0.2 include a methoxy group (-0.27), an ethoxy group (-0.24), an n-propoxy group (-0.25), an isopropoxy group (-0.45), and an n-butoxy group (-0.32). On the other hand, a fluorine atom (0.06), a methyl group (-0.17), an ethyl group (-0.15), a tert-butyl group (-0.20), an n-hexyl group (-0.15), a cyclohexyl group (-0.15), etc. are not substituents having a Hammett σp value of less than -0.2. In one embodiment of the present invention, １ ~R ９ It is possible to adopt a compound having three or four substituents with a Hammett's σp value of less than −0.2 present in R １ ~R ７ Preferably, the number of substituents present in R having a Hammett's σp value of less than −0.2 is three or more, and for example, a compound having three or four substituents can be used. ８ and R ９ In general formula (16), R may not have a substituent with a Hammett σp value of less than −0.2. １ , R ３ , R ４ , R ５ , R ７ The number of substituents having a Hammett's σp value of less than −0.2 present in R is preferably three or more, and for example, a compound having three or four substituents can be used. ２ , R ６ , R ８ , R ９ In a preferred embodiment of the present invention, R １ , R ４ , R ７ Each of these groups has a substituent with a Hammett σp value of less than −0.2.

[0080] In the present invention, a compound containing a carbazole structure may be selected as the light-emitting material used in combination with the assist dopant, or a compound containing no carbazole structure, dibenzofuran structure, or dibenzothiophene structure may be selected as the light-emitting material used in combination with the assist dopant.

[0081] Preferred compounds that can be used as luminescent materials in combination with an assist dopant are listed below. However, the luminescent materials that can be used in combination with an assist dopant in the present invention should not be construed as being limited by the specific examples below. In the structural formulas of the following exemplary compounds, t-Bu represents a tertiary butyl group (tert-butyl group).

[0082] Derivatives of the above-exemplified compounds include compounds in which at least one hydrogen atom is substituted with a deuterium atom, an alkyl group, an aryl group, a heteroaryl group, or a diarylamino group. In addition, the compounds described in paragraphs 0220 to 0239 of WO2015 / 022974 can also be preferably used as light-emitting materials to be used in combination with an assist dopant.

[0083] (Substrate) 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.

[0084] 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 higher). In some embodiments, the metal is Au. In some embodiments, the conductive transparent material is CuI, indium tin oxide (ITO), SnO ２ and ZnO. In some embodiments, IDIXO (In２ O ３ An amorphous material capable of forming a transparent conductive film, such as 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 accurate (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, when emitted light passes through the anode, the anode has a transmittance of more than 10%, and the anode has a sheet resistance of several hundred ohms per unit area or less. In some embodiments, the thickness of the anode is 10 to 1,000 nm. In some embodiments, the thickness of the anode is 10 to 200 nm. In some embodiments, the thickness of the anode varies depending on the material used.

[0085] 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), an alloy, a conductive compound, or a combination thereof. In some embodiments, the electrode material is sodium, sodium-potassium alloy, magnesium, lithium, magnesium-copper mixture, magnesium-silver mixture, magnesium-aluminum mixture, magnesium-indium mixture, aluminum-aluminum oxide (Al ２ O ３ In some embodiments, a mixture of an electron-injecting metal and a second metal is used, the second metal being a stable metal having a higher work function than the electron-injecting metal. In some embodiments, the mixture is selected from a magnesium-silver mixture, a magnesium-aluminum mixture, a magnesium-indium mixture, an aluminum-aluminum oxide (Al ２ O ３) mixture, a lithium-aluminum mixture, and aluminum. In some embodiments, the mixture improves electron injection properties and oxidation resistance. In some embodiments, the cathode is fabricated by forming an 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, either the anode or the 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 semitransparent cathode. In some embodiments, the device includes an anode and a cathode, both of which are transparent or semitransparent.

[0086] Injection Layer The injection layer is a layer between the electrode and the organic layer. In some embodiments, the injection layer reduces the driving voltage and enhances the 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 light emitting layer or the hole transport layer, and between the cathode and the light emitting layer or the electron transport layer. In some embodiments, the injection layer is present. In some embodiments, the injection layer is not present. Below are examples of preferred compounds that can be used as hole injection materials.

[0087]

[0088] Next, preferred examples of compounds that can be used as the electron injection material will be listed.

[0089] (Barrier Layer) A barrier layer is a layer that can prevent charges (electrons or holes) and / or excitons present in the light-emitting layer from diffusing 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 barrier 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 term "electron blocking layer" or "exciton blocking layer" includes a layer that has both the functions of an electron blocking layer and an exciton blocking layer.

[0090] (Hole Blocking Layer) The hole blocking layer functions as an electron transporting layer. In some embodiments, during electron transport, the hole blocking layer prevents holes from reaching the electron transporting layer. In some embodiments, the hole blocking layer increases the probability of recombination of electrons and holes in the light-emitting layer. The material used for the hole blocking layer may be the same material as described above for the electron transporting layer. Below are examples of preferred compounds that can be used for the hole blocking layer.

[0091]

[0092] (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.

[0093] (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 the following properties: hole injection or transport and electron blocking. 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 a porphyrin compound, an aromatic tertiary amine compound, and a styrylamine compound. 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.

[0094]

[0095] 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.

[0096]

[0097] 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.

[0098]

[0099] While specific examples of preferred materials that can be used in organic electroluminescent devices have been given, the materials that can be used in the present invention are not limited to the exemplified compounds. Furthermore, even compounds exemplified as materials having specific functions can be used as materials having other functions. Each organic layer of an organic electroluminescent device can be formed by a wet process. In the wet process, a solution containing a composition containing compounds constituting the organic layer is applied to a surface, and a layer is formed after removing the solvent. 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 the wet process, an appropriate organic solvent capable of dissolving the compounds constituting the organic layer 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 compounds constituting the organic layer. In some embodiments, the organic layer can be formed by a dry process. In some embodiments, the dry process can be a vacuum deposition method, but is not limited to this. When using vacuum deposition, the compounds constituting the organic layer may be co-deposited from separate deposition sources, or from a single deposition source containing a mixture of compounds. When using a single deposition source, a mixed powder of compound powders may be used, a compressed compact of the mixed powder may be used, or a mixture of the compounds may be used by heating, melting, and cooling the mixture. In some embodiments, co-deposition is performed under conditions where the deposition rates (weight loss rates) of the multiple compounds contained in a single deposition source are identical or nearly identical, thereby forming an organic layer having a composition ratio corresponding to the composition ratio of the multiple compounds contained in the deposition source. By mixing multiple compounds in the same composition ratio as the composition ratio of the organic layer to be formed as a deposition source, an organic layer having the desired composition ratio can be easily formed. In some embodiments, the temperature at which the weight loss rate of each co-deposited compound is the same can be identified, and that temperature can be used as the temperature during co-deposition.

[0100] Devices. In some embodiments, the light-emitting layer is incorporated into a device. For example, devices include, but are not limited to, OLED bulbs, OLED lamps, television displays, computer monitors, mobile phones, and tablets. In some embodiments, 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 the device and / or as hole transport materials. Such devices include, for example, 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-quenched devices (O-FQDs), light-emitting fuel cells (LECs), or organic laser diodes (O-lasers).

[0101] Bulb or Lamp In some embodiments, an 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 comprises OLEDs of different colors. In some embodiments, the device comprises an array comprising 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 is an OLED light comprising: 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 an emissive 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 has multiple OLEDs mounted on the circuit board such that light is emitted in multiple directions. In some embodiments, a portion 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.

[0102] Displays or Screens In some embodiments, the light-emitting layers of the present invention can be used in screens or displays. In some embodiments, the compounds of the present invention are deposited onto a substrate using processes such as, but not limited to, vacuum evaporation, deposition, 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 on 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 in pixel regions protects etching in certain areas until these specific patterns are undercut and removed from the substrate. At that time, all pixel areas experience similar etching rates, but their 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 a pixel, enabling the deep, localized etching required to create steep vertical bevel angles. A preferred material for the deposition mask is Invar. Invar is a metal alloy cold-rolled into long, thin sheets at steel mills. Invar cannot be electrodeposited onto a spin mandrel as a nickel mask. A suitable, low-cost method for creating open areas in a 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.

[0103] [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.

[0104] Another aspect of the present invention provides a method for manufacturing an organic light-emitting diode (OLED) display, the method including: forming a barrier layer on a base substrate of a mother panel; forming a plurality of display units on the barrier layer in cell panel units; forming an encapsulation layer on each of the display units of the cell panel; and applying an organic film to an interface between the cell panels. In some embodiments, the barrier layer is an inorganic film, for example, made of SiNx, and edges of the barrier layer are covered with an organic film made of polyimide or acrylic. In some embodiments, the organic film assists in soft cutting of the mother panel into cell panel units. 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 made of the same material as the planarization film and is formed simultaneously with the formation of the planarization film. In some embodiments, the light-emitting units are coupled to the TFT layer by a passivation layer, a planarization film therebetween, and an encapsulation layer that covers and protects the light-emitting units. In some embodiments of the manufacturing method, the organic film is not coupled to either the display unit or the encapsulation layer.

[0105] 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 a 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, like the organic film formed on the edge of the barrier layer, is formed of polyimide or acrylic. In some embodiments, the planarization film and the organic film are formed simultaneously during the manufacture of the OLED display. In some embodiments, the organic film may be formed on the edge of the barrier layer, such that a portion of the organic film is in direct contact with the base substrate and a remaining portion of the organic film is in contact with the barrier layer while surrounding the edge of the barrier layer.

[0106] In some embodiments, the light-emitting layer includes a pixel electrode, a counter electrode, and an organic light-emitting layer disposed between the pixel electrode and the counter electrode. In some embodiments, the pixel electrode is connected 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, an appropriate voltage is formed between the pixel electrode and the counter electrode, causing the organic light-emitting layer to emit light, thereby forming an image. Hereinafter, an image-forming unit including a TFT layer and a light-emitting unit is referred to as a display unit. In some embodiments, an encapsulation layer that covers the display unit 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 a distance from each of the multiple display units. In some embodiments, the organic film is formed 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.

[0107] In one embodiment, the OLED display is flexible and uses a flexible base substrate made of polyimide. In some embodiments, the base substrate is formed on a carrier substrate made of a glass material, and then the carrier substrate is separated. In some embodiments, a barrier layer is formed on the surface of the base substrate opposite the carrier substrate. In one embodiment, the barrier layer is patterned according to the size of each cell panel. For example, 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.

[0108] 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 into the base substrate. In some embodiments, a TFT layer of each cell panel is formed, and a passivation layer, which is an inorganic film, and a planarization film, which is an organic film, are disposed on and cover the TFT layer. At the same time as the planarization film, made of, for example, polyimide or acrylic, is formed, the grooves at the interface are covered with an organic film, made of, for example, 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 impact that occurs. That is, if all barrier layers were completely exposed without the organic film, the impact would be transmitted to the barrier layer when each cell panel is 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 impact that would otherwise be transmitted to the barrier layer, allowing each cell panel to be cut softly and preventing cracks from occurring in the barrier layer. In one embodiment, the organic film and the planarization film covering the groove of the interface portion are spaced apart from each other. For example, if the organic film and the planarization film are connected to each other as one layer, external moisture may penetrate into the display unit through the planarization film and the remaining portion of the organic film, so the organic film and the planarization film are spaced apart from each other such that the organic film is spaced apart from the display unit.

[0109] In some embodiments, the display units are formed by forming light-emitting units, and an encapsulation layer is disposed on the display units to cover the display units. Thus, after the mother panel is completely manufactured, the carrier substrate supporting the base substrate is separated from the base substrate. In some embodiments, a laser beam is irradiated onto the carrier substrate, causing the carrier substrate to separate 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 interfaces between the cell panels using a cutter. In some embodiments, the grooves at the interfaces along which the mother panel is cut are covered with an organic film, which absorbs impact during cutting. In some embodiments, cracks in the barrier layer can be prevented during cutting. In some embodiments, the method reduces the product defect rate and stabilizes its quality. Another aspect is an OLED display having a barrier layer formed on a base substrate, display units formed on the barrier layer, an encapsulation layer formed on the display units, and an organic film applied to edges of the barrier layer.

[0110] The features of the present invention will be explained in more detail below with reference to synthesis examples and working examples. 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 measuring device (Newport: 1930C), an optical spectrometer (Ocean Optics: USB2000), a spectroradiometer (Topcon: SR-3), and a streak camera (Hamamatsu Photonics K.K.: C4334 model).

[0111] (Synthesis Example 1) Synthesis of Compound 1a

[0112] 2-Bromo-4-fluoro-1-nitrobenzene (5.13 g, 23.3 mmol), 5H-benzofuro[3,2-c]carbazole (5 g, 19.4 mmol), and potassium carbonate (5.37 g, 38.9 mmol) were dissolved in 50 ml of DMF (dimethylformamide) and stirred at 100°C for 3 hours. The reaction solution was cooled to room temperature, and water was added. The resulting precipitate was filtered and washed with water and methanol to obtain intermediate A (8.33 g, 94%) as a white solid. 1 H NMR (500MHz, CDCl3, δ): 8.58 (d, J= 9 Hz, 1H), 8.19 (d, J = 9 Hz, 2H), 8.09 (s, 1H), 8.03-7.98 (m, 2H), 7.80 (d, J = 9 Hz, 1H), 7.75 (d, J = 9 Hz, 1H), 7.54-7.38 (m, 5H). MS (ASAP): 457.73 (M+H + ). Calcd. for C 24 H 13 BrN2O3: 456.01.

[0113]

[0114] Intermediate A (4.57 g, 10 mmol), 3-(9H-carbazol-9-yl)phenylboronic acid (3.16 g, 11 mmol), tetrakistriphenylphosphinepalladium(0) (0.58 g, 0.5 mmol), and potassium carbonate (4.15 g, 30 mmol) were dissolved in a mixed solution of THF (tetrahydrofuran) and water (200 / 100 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 and dried over magnesium sulfate, followed by removal of the solvent. The resulting solid was purified by silica gel column chromatography (developing solvent: hexane:chloroform = 1:1) to obtain Intermediate B (6.3 g, 100%) as an orange solid. 1H NMR (500MHz, CDCl3, δ): 8.58 (d, J = 8 Hz, 1H), 8.28 (d, J = 9 Hz, 1H), 8.15 (d, J = 8 Hz, 2H), 8.02 -7.96 (m, 2H),7.88 -7.84 (m, 2H), 7.77-7.64 (m, 4H), 7.58 -7.38 (m, 11H), 7.30 (t, J= 9 Hz, 2H). MS (ASAP): 620.04 (M+H + ). Calcd. for C 42 H 25 N3O3: 619.19.

[0115]

[0116] Intermediate B (6 g, 9.68 mmol) was added to 50 mL of triethyl phosphite and refluxed for 12 hours. The reaction solution was cooled to remove the triethyl phosphite. The resulting solid was purified by silica gel column chromatography (developing solvent: chloroform) to obtain Intermediate C (1.44 g, 25%) as a light brown solid. 1 H NMR (500MHz, CDCl3, δ): 8.58 (d, J= 9 Hz, 1H), 8.51 (bs, 1H), 8.25 (s, 1H), 8.21 (s, 1H)8.15 (d, J = 9 Hz, 2H), 7.96 (d, J = 8 Hz, 1H), 7.90 (d, J = 8 Hz, 1H), 7.78-7.61 (m, 5H), 7.48-7.27 (m, 12H). MS (ASAP): 588.23 (M+H + ). Calcd. for C 42 H 25 N3O: 587.20.

[0117]

[0118] Intermediate C (1.4 g, 2.38 mmol), benzene iodoide (0.97 g, 4.76 mmol), tris(dibenzylideneacetone)dipalladium(0) (0.22 g, 0.24 mmol), tri-tert-butylphosphonium tetrafluoroborate (0.14 g, 0.48 mmol), and sodium tert-butoxide (0.46 g, 4.76 mmol) were added to 50 ml of toluene and refluxed for 24 hours. The reaction solution was cooled to room temperature, and insoluble matter was removed by filtration through Celite. The solvent was then removed to obtain a solid. The resulting solid was purified by silica gel column chromatography (developing solvent: hexane:toluene = 7:3). Further recrystallization from toluene yielded Compound 1a (1.16 g, 73%) as a white solid. 1 H NMR (500MHz, CDCl3, δ): 8.59 (d, J = 9 Hz, 1H), 8.34 (s, 1H), 8.30 (s, 1H), 8.16 (d, J = 9Hz, 2H), 7.97 (d, J = 8 Hz, 1H), 7.93 (d, J= 8 Hz, 1H), 7.78-7.58 (m, 9H), 7.48-7.34 (m, 10H), 7.39-7.33 (m, 2H), 7.19-7.13 (m, 1H). MS (ASAP): 664.20 (M+H) + ). Calcd. for C 48 H 29 N3O: 663.23.

[0119] (Synthesis Example 2) Synthesis of Compound 2a

[0120] 3,6-Dibromo-9-phenylcarbazole (2.5 g, 6.23 mmol), 5H-benzofuro[3,2-c]carbazole (4.0 g, 15.6 mmol), tris(dibenzylideneacetone)dipalladium(0) (570 mg, 0.623 mmol), tri-tert-butylphosphonium tetrafluoroborate (361 mg, 1.25 mmol), and sodium tert-butoxide (1.80 mg, 18.7 mmol) were added to 100 mL of toluene and refluxed for 24 hours. The reaction solution was cooled to room temperature and filtered through Celite to remove insoluble matter. The solvent was then removed to obtain a solid. The resulting solid was purified by silica gel column chromatography (developing solvent: hexane:toluene = 7:3). Further recrystallization from toluene yielded compound 2a (3.99 g, 85%) as a white solid. 1 H NMR (500MHz, CDCl3, δ): 8.58 (d, J = 10 Hz, 2H), 8.36 (s, 2H), 7.98-7.90 (m, 4H), 7.79-7.58 (m, 11H), 7.48-7.34 (m, 12H). MS (ASAP): 754.20 (M+H + ). Calcd for C 54 H 31 N3O2: 753.24.

[0121] (Synthesis Example 2) Synthesis of Compound 2b

[0122] 3,6-Dibromo-9-phenylcarbazole (0.82 g, 2.04 mmol), phenylbenzofurocarbazole D (1.70 g, 5.1 mmol), tris(dibenzylideneacetone)dipalladium(0) (0.18 g, 0.2 mmol), tri-tert-butylphosphonium tetrafluoroborate (0.12 g, 0.41 mmol), and sodium tert-butoxide (0.39 g, 4.08 mmol) were added to 30 ml of toluene and refluxed for 24 hours. The reaction solution was cooled to room temperature and filtered through Celite to remove insoluble matter. The solvent was then removed to obtain a solid. The resulting solid was purified by silica gel column chromatography (developing solvent: hexane:toluene = 7:3). Further recrystallization from toluene / methanol yielded compound 2b (3.99 g, 85%) as a white solid. MS (MALDI): 906.06 (M+H + ). Calcd for C 66 H 39 N3O2: 905.30.

[0123] (Example 1) Each thin film was formed on a glass substrate on which an anode made of indium tin oxide (ITO) with a film thickness of 50 nm was formed by vacuum deposition at a vacuum degree of 5.0 × 10 －５ The layers were laminated at 100 Pa. First, HAT-CN was formed on ITO to a thickness of 10 nm, and NPD was formed thereon to a thickness of 30 nm. Next, compound 1a was formed to a thickness of 10 nm, and H1 was formed thereon to a thickness of 5 nm. Next, T63 and H1 were co-deposited from different evaporation sources to form a 40 nm thick layer, which served as an emissive layer. The concentrations of T63 and H1 in the emissive layer were 45% by mass and 55% by mass, respectively. Next, SF3-TRZ was formed to a thickness of 10 nm, and then Liq and SF3-TRZ were co-deposited from different evaporation sources to form a 30 nm thick layer. The concentrations of Liq and SF3-TRZ in this layer were 30% by mass and 70% by mass, respectively. Liq was further formed to a thickness of 2 nm, and then aluminum (Al) was deposited to a thickness of 100 nm to form a cathode, resulting in an organic electroluminescent element (EL element 1).

[0124] Comparative Example 1 An organic electroluminescence element (comparative EL element 1) was produced by carrying out the same steps as in Example 1, except that comparative compound 1 was used instead of compound 1a.

[0125] (Test) EL element 1 and comparative EL element 1 were each 12.6 mA / cm ２ The time (LT95) until the luminous intensity reached 95% of the initial luminous intensity was measured. As a result, the relative value of EL element 1 was 1.40, where the value of comparative EL element 1 was set to 1.00, and it was confirmed that the use of the compound represented by general formula (1) extended the element life by as much as 40%.

[0126] Example 2 An organic electroluminescence element (EL element 2) was fabricated by performing the same steps as in Example 1, except that compound 2a was used instead of compound 1a. It was confirmed that EL element 2 also had a longer element life than comparative EL element 1.

[0127] Example 3 An organic electroluminescence element (EL element 3) was fabricated by performing the same steps as in Example 1, except that compound 2b was used instead of compound 1a and T63 was changed to T64. EL element 3 had a 15% longer element life than an EL element using compound 1a instead of compound 2b.

[0128]

[0129] The compound of the present invention is useful as an electron blocking material and can be used in organic semiconductor devices. When the compound of the present invention is used in the electron blocking layer of an organic electroluminescence device, the device life can be extended. Therefore, the present invention has high industrial applicability.

[0130] REFERENCE SIGNS LIST 1 substrate 2 anode 3 hole injection layer 4 hole transport layer 5 electron blocking layer 6 underlayer 7 light-emitting layer 8 hole blocking layer 9 electron transport layer 10 electron injection layer 11 cathode

Claims

1. A compound represented by the following general formula (1). General formula (1) 【Chemical 1】 In general formula (1), X represents a donor group, and R １ ~R ６ each independently represents a deuterium atom or a substituent. n1 and n2 each independently represent an integer of 0 to 4, n3 represents an integer of 0 to 2, n4 and n6 each independently represent an integer of 0 to 3, and n5 represents an integer of 0 to 5. Two adjacent R １ , two adjacent R ２ , two adjacent R ３ , two adjacent R ４ , two adjacent R ５ , two adjacent R ６ may be bonded to each other to form a cyclic structure.]

2. The compound according to Claim 1, represented by the following general formula (2A). General formula (2A) [Chemical 2] In general formula (2A), R １ ~R ８ each independently represents a deuterium atom or a substituent. n1, n2, n7, and n8 each independently represent an integer of any one of 0 to 4, n3 represents an integer of any one of 0 to 2, n4 and n6 each independently represent an integer of any one of 0 to 3, and n5 represents an integer of any one of 0 to 5. Two adjacent R １ , two adjacent R ２ , two adjacent R ３ , two adjacent R ４ , two adjacent R ５ , two adjacent R ６ , two adjacent R ７ , two adjacent R ８ may be bonded to each other to form a cyclic structure.]

3. The compound according to Claim 1, represented by the following general formula (2B). General formula (2B) [Chemical Formula 3] [In general formula (2B), R １ ~R ９ each independently represents a deuterium atom or a substituent. n1, n2, n8, and n9 each independently represent an integer of any one of 0 to 4, n3 and n7 each independently represent an integer of any one of 0 to 2, n4 and n6 each independently represent an integer of any one of 0 to 3, and n5 represents an integer of any one of 0 to 5. Two adjacent R １ , two adjacent R ２ , two adjacent R ３ , two adjacent R ４ , two adjacent R ５ , two adjacent R ６ , two adjacent R ７ , two adjacent R ８ , two adjacent R ９ may be bonded to each other to form a cyclic structure. ]

4. The compound according to Claim 1, represented by the following general formula (3A). General formula (3A) 【Chemical 4】 In general formula (3A), R １ ~R １１ each independently represents a deuterium atom or a substituent. n1, n4, n6, n7, and n8 are each independently any integer from 0 to 3, n2 is any integer from 0 to 4, n3 is any integer from 0 to 2, and n5, n9, n10, and n11 each independently represent any integer from 0 to 5. Two adjacent R １ , two adjacent R ２ , two adjacent R ３ , two adjacent R ４ , two adjacent R ５ , two adjacent R ６ , two adjacent R ７ , two adjacent R ８ , two adjacent R ９ , two adjacent R １０ , two adjacent R １１ may be bonded to each other to form a cyclic structure.]

5. The compound according to Claim 1, represented by the following general formula (3B). General formula (3B) [Chemical Formula 5] In general formula (3B), R １ to R １１ each independently represents a deuterium atom or a substituent. n1, n4, n6, and n8 are each independently an integer of 0 to 3, n2 and n9 are each independently an integer of 0 to 4, n3 and n7 are each independently an integer of 0 to 2, and n5, n10, and n11 represent an integer of 0 to 5. Two adjacent R １ , two adjacent R ２ , two adjacent R ３ , two adjacent R ４ , two adjacent R ５ , two adjacent R ６ , two adjacent R ７ , two adjacent R ８ , two adjacent R ９ , two adjacent R １０ , two adjacent R １１ may be bonded to each other to form a cyclic structure.]

6. An electron barrier material containing the compound according to any one of Claims 1 to 5.

7. An organic semiconductor device containing the compound according to any one of Claims 1 to 5.

8. The organic semiconductor device according to Claim 7, wherein the organic semiconductor device is an organic electroluminescence device having an anode, a cathode, and at least two organic layers including a light-emitting layer between the anode and the cathode.

9. The organic semiconductor device according to Claim 8, wherein the light-emitting layer contains a host material and a delayed fluorescence material.

10. The organic semiconductor device according to Claim 8, wherein the light-emitting layer contains a host material, a delayed fluorescence material, and a fluorescent emission material, and the emission amount from the fluorescent emission material is the largest among the emissions from the device.

11. The organic semiconductor device according to any one of Claims 8 to 10, having an organic layer containing the compound between the anode and the light-emitting layer.

12. The organic semiconductor device according to any one of Claims 8 to 11, wherein the organic layer containing the compound is adjacent to the light-emitting layer.

13. The organic semiconductor device according to any one of Claims 8 to 11, having a laminated structure in which the organic layer containing the compound, an underlayer, and the light-emitting layer are laminated in this order, and the organic layer containing the compound and the light-emitting layer are not in contact with each other.

14. The organic semiconductor device according to Claim 13, wherein the underlayer contains a host material contained in the light-emitting layer.

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