Organic light-emitting element, method for designing same, and program

Abstract

In an organic light-emitting element having a composition containing a first host material, a second host material having a higher HOMO energy level than the first host material, a delayed fluorescent material, and a light-emitting material, if EHOMO (H2)-EHOMO (T) < = 0.33 eV, high luminous efficiency can be achieved. EHOMO (H2) and EHOMO (T) are the HOMO energy levels of the second host material and the delayed fluorescent material, respectively.

Description

Technical Field

[0001] The present invention relates to an organic light emitting element with high light emitting efficiency, and also to a design method of an organic light emitting element capable of designing an organic light emitting element with high light emitting efficiency and a program for implementing the design method. Background Art

[0002] Active research is being conducted to improve the luminous efficiency of organic light-emitting elements such as organic electroluminescent elements. In particular, various studies are being conducted to convert triplet excited state energy that deactivates without radiation at room temperature into singlet excited state energy and use it for luminescence by newly developing the material composition of the light-emitting layer of the organic electroluminescent element.

[0003] For example, a Hyper type organic electroluminescent element containing a host material, a delayed fluorescent material and a fluorescent material in a light-emitting layer is proposed. In the Hyper type light-emitting layer, the excited triplet energy transferred from the host material to the delayed fluorescent material and the excited triplet energy generated in the delayed fluorescent material are converted into excited singlet energy by reverse intersystem crossing from the triplet state in the delayed fluorescent material to the singlet state, and transferred to the fluorescent material as fluorescent radiation. Thus, the excited triplet energy generated in the light-emitting layer is effectively used in the light emission of the fluorescent material, so that high luminous efficiency can be obtained.

[0004] However, the above-mentioned Hyper-type light-emitting layer is usually constructed by using a hole-transporting material as the main material, and the delayed fluorescent material also has the function of an electron-transporting main material. Therefore, the hole transport property is superior to the electron transport property in any case, and the carrier re-bonding area is biased toward the hole blocking layer (or electron transport layer) side, so the delayed fluorescent material deteriorates due to continuous driving, which becomes the reason for shortening the life of the element.

[0005] As a countermeasure to this, it is considered to use two main materials, hole transporting main body and electron transporting main body, in the light-emitting layer to improve the carrier balance. As a light-emitting element using two main materials, Patent Document 1 proposes an organic light-emitting element containing a first main body with a HOMO energy level of -5.6eV to -6.4eV and a second main body with a HOMO energy level of -5.4eV to -5.8eV in the light-emitting layer, and records that the hole injection barrier of the light-emitting layer is reduced by this structure to improve the element life.

[0006] Previous technical literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application Publication No. 2019-506729 Summary of the invention

[0009] Technical issues to be solved by the invention

[0010] As mentioned above, Patent Document 1 describes the use of two host materials with different HOMO energy levels to improve the device life. However, the present inventors have clearly learned that when a host material with a HOMO energy level in the range of -5.4 eV to -5.8 eV is used in combination with a conventional hole-transporting host material in the light-emitting layer, the photoluminescence quantum yield is significantly reduced compared to the case where only the hole-transporting host material is used in the host. It is believed that this is because the interaction that would not occur in a single host due to the use of two host materials affects the light-emitting process. Therefore, in a system using multiple host materials, there is a problem that it is difficult to improve the light-emitting efficiency of the organic light-emitting element.

[0011] Therefore, the present inventors have conducted intensive studies with the aim of providing an organic light-emitting element that can achieve high light-emitting efficiency while using two host materials.

[0012] Means for solving technical problems

[0013] As a result of in-depth research, the present inventors have clearly learned that the significant reduction in luminous efficiency observed in a system using a host material having a HOMO energy level in the range of -5.4eV to -5.8eV is due to the high energy level of the HOMO of the host material, which causes electron transfer between the HOMO of the host molecule and the LUMO of the delayed fluorescent molecule, thereby forming an exciplex. In addition, it has been found that even in an organic electroluminescent element containing two host materials in the light-emitting layer, a high level of luminous efficiency can be ensured as long as the energy level of the HOMO of the host material is not too high compared to the energy level of the HOMO of the delayed fluorescent material.

[0014] The present invention has been made based on this finding, and specifically has the following structure.

[0015] [1] An organic light-emitting element having a composition comprising a first host material, a second host material having a higher HOMO energy level than the first host material, a delayed fluorescence material, and a light-emitting material, and satisfying the following formula (a).

[0016] E HOMO (H 2 )-E HOMO (T)≤0.33eV Formula (a)

[0017] [In the above formula, E HOMO (H 2 ) represents the HOMO energy level of the second host material (unit: eV), E HOMO(T) represents the energy level of HOMO of the delayed fluorescent material (unit: eV).]

[0018] [2] The organic light-emitting element according to [1], wherein

[0019] The first host material, the second host material, the delayed fluorescent material, and the light-emitting material satisfy the following formula (b).

[0020] E HOMO (H 1 )<E HOMO (H 2 )≤E HOMO (T)≤E HOMO (E) Formula (b)

[0021] [In formula (b), E HOMO (H 1 ) represents the HOMO energy level of the first host material, E HOMO (H 2 ) represents the HOMO energy level of the second host material, E HOMO (T) represents the energy level of the HOMO of the delayed fluorescent material, E HOMO (E) represents the energy level of the HOMO of the luminescent material.]

[0022] [3] The organic light-emitting element according to [1], wherein

[0023] The first host material, the second host material, the delayed fluorescent material, and the light-emitting material satisfy the following formula (c).

[0024] E HOMO (H 1 )<E HOMO (T)<E HOMO (H 2 )≤E HOMO (E) Formula (c)

[0025] [In formula (c), E HOMO (H 1 ) represents the HOMO energy level of the first host material, E HOMO (H 2 ) represents the HOMO energy level of the second host material, E HOMO (T) represents the energy level of the HOMO of the delayed fluorescent material, E HOMO (E) represents the energy level of the HOMO of the luminescent material.]

[0026] [4] The organic light-emitting element according to any one of [1] to [3], wherein

[0027] The concentration of the first host material in the composition is 0.3 to 3.0 times the concentration of the second host material.

[0028] [5] The organic light-emitting element according to any one of [1] to [4], wherein

[0029] The first host material and the second host material have a structure represented by any one of the following general formulas (1) to (3).

[0030] [Chemical formula 1]

[0031] General formula (1)

[0032]

[0033] [In the general formula (1), X represents O, S or N (R 6 ), R 1 ~R 5 Each independently represents a deuterium atom or a substituent, R 6 represents a deuterium atom, an alkyl group, an aryl group, or a group composed of an alkyl group and an aryl group. n1 and n2 each independently represent an integer from 0 to 5, n3 represents an integer from 0 to 4, n4 represents an integer from 0 to 2, and n5 represents an integer from 0 to 4. Two adjacent R 1 , two adjacent R 2 , two adjacent R 3 , two adjacent R 4 , two adjacent R 5 Can bond to each other to form a ring structure.]

[0034] [Chemical formula 2]

[0035] General formula (2)

[0036]

[0037] [In general formula (2), R 11 ~R 13 Each of n11 and n12 independently represents an integer from 0 to 5, and n13 represents an integer from 1 to 5. 11 , two adjacent R 12 , two adjacent R 13 can bond to each other to form a ring structure. 13 When the two groups are bonded to each other to form a benzofurano structure or a benzothiopheno structure, there is a group containing a dibenzofurano structure or a dibenzothiophene structure or a group containing a cyano group as R 13 . ]

[0038] [Chemical formula 3]

[0039] General formula (3)

[0040]

[0041] [In general formula (3), R 21 represents a group containing a dibenzofuran structure, R 22 ~R 24 Each independently represents a deuterium atom or a substituent. n22 to n24 each independently represent an integer from 0 to 4. Two adjacent R 22 , two adjacent R 23 , two adjacent R 24 can bond to each other to form a ring structure. 24 When the benzofurano structure or benzothiopheno structure is formed by bonding to each other, there is an aryl group which may be substituted by an alkyl group as R 24 . ]

[0042] [6] The organic light-emitting element according to [5], wherein

[0043] The first host material is a compound represented by the general formula (3), and the second host material is a compound represented by the general formula (1) or (2).

[0044] [7] The organic light-emitting element according to [5], wherein

[0045] The first host material and the second host material are compounds represented by the general formula (3).

[0046] [8] The organic light-emitting element according to any one of [1] to [7], wherein

[0047] The delayed fluorescent material is a substituted benzonitrile compound or a compound having a phenazine skeleton.

[0048] [9] The organic light-emitting element according to any one of [1] to [8], wherein

[0049] The organic light-emitting element is an organic electroluminescent element, and the light-emitting layer of the organic electroluminescent element comprises the composition.

[0050]

[10] A method for designing an organic light-emitting element, which is a method for designing an organic light-emitting element having a composition, the composition comprising a first host material, a second host material having a higher HOMO energy level than the first host material, a delayed fluorescent material, and a light-emitting material, wherein:

[0051] The HOMO energy level of the second host material isHOMO (H 2 ) and the energy level E of the HOMO of the delayed fluorescent material HOMO (T) The second host material and the delayed fluorescent material are combined so as to satisfy the following formula (a).

[0052] E HOMO (H 2 )-E HOMO (T)≤0.33eV Formula (a)

[0053]

[11] A program for implementing the method described in

[10] .

[0054] Effects of the Invention

[0055] The organic light-emitting element of the present invention can ensure high light-emitting efficiency while using two host materials. In addition, according to the design method of the present invention, an organic light-emitting element with high light-emitting efficiency can be designed using two host materials. DETAILED DESCRIPTION

[0056] The content of the present invention is described in detail below. The description of the constituent elements described below is sometimes based on representative embodiments or specific examples of the present invention, but the present invention is not limited to such embodiments or specific examples. In addition, in this article, the numerical range represented by "to" means a range that includes the numerical values ​​described before and after "to" as the lower limit and upper limit. And, in this article, "consisting of to" means only the composition described before "consisting of to", and does not include the content other than this. In addition, part or all of the hydrogen atoms present in the molecules of the compounds used in the present invention can be replaced by deuterium atoms ( 2 H, deuterium (D) substitution. In the chemical structural formula of this article, the hydrogen atom is represented by H or its representation is omitted. For example, when the representation of the atom that forms a carbon atom bond with the ring skeleton of the benzene ring is omitted, H forms a carbon atom bond with the ring skeleton at the omitted position. In this article, the term "substituent" means an atom or atomic group other than a hydrogen atom and a deuterium atom. On the other hand, expressions such as "substituted or unsubstituted" and "can be substituted" mean that the hydrogen atom can be substituted by a deuterium atom or a substituent. In addition, "transparent" in the present invention refers to a transmittance of visible light of more than 50%, preferably more than 80%, more preferably more than 90%, and further preferably more than 99%. Regarding the transmittance of visible light, it can be measured by a UV-visible spectrophotometer.

[0057] The organic light-emitting device of the present invention has a composition including a first host material, a second host material, a delayed fluorescent material, and a light-emitting material.

[0058] The second host material has a higher HOMO energy level than the first host material. "HOMO" in the present invention is an abbreviation for Highest occupied Molecular Orbital, and the "HOMO energy level" can be obtained by atmospheric photoelectron spectroscopy (AC-3 manufactured by RIKEN KEIKI CO., LTD., etc.). The organic light-emitting element of the present invention is characterized in that the HOMO energy level E of the second host material is HOMO (H 2 ) and the HOMO energy level E of the delayed fluorescent material HOMO (T) satisfies the following formula (a).

[0059] E HOMO (H 2 )-E HOMO (T)≤0.33eV Formula (a)

[0060] E HOMO (H 2 )-E HOMO (T) is preferably greater than -0.30eV, more preferably greater than -0.25eV. In one aspect of the present invention, it can be set in a range of greater than -0.30eV and less than 0eV to suppress the reduction in luminous efficiency caused by the simultaneous use of two host materials. For example, it can also be set in a range of greater than -0.30eV and less than -0.15eV or in a range of greater than -0.15eV and less than 0eV. Furthermore, in one aspect of the present invention, it can also be set to greater than 0eV and less than 0.33eV to improve luminous efficiency. For example, it can also be set in a range of greater than 0eV and less than 0.15eV, in a range of greater than 0.15eV and less than 0.25eV, or in a range of greater than 0.25eV and less than 0.33eV. In one aspect of the present invention, E HOMO (H 2 )<E HOMO (T). In one aspect of the present invention, E HOMO (H 2 )>E HOMO (T).

[0061] Energy level E of HOMO of the first host material HOMO (H 1 ) and the HOMO energy level E of the delayed fluorescent material HOMO (T) is preferably E HOMO (H 1 )<E HOMO (T) +0.1eV. HOMO (T)-E HOMO (H 1) is preferably greater than -0.10 eV and less than 0.70 eV. For example, it may be set within a range of greater than -0.10 eV and less than 0.30 eV, within a range of greater than -0.10 eV and less than 0.10 eV, or within a range of greater than 0 eV and less than 0.10 eV.

[0062] Energy level E of HOMO of the first host material HOMO (H 1 ) is greater than the HOMO energy level E of the second host material. HOMO (H 2 ) is lower. HOMO (H 2 )-E HOMO (H 1 ) is preferably greater than 0 eV and less than 0.40 eV. For example, it may be set within a range of greater than 0 eV and less than 0.15 eV, within a range of greater than 0.15 eV and less than 0.25 eV, or within a range of greater than 0.25 eV and less than 0.40 eV.

[0063] In one aspect of the present invention, the HOMO energy level E of the first host material is HOMO (H 1 ), the energy level E of the HOMO of the second host material HOMO (H 2 ), the energy level E of the HOMO of the delayed fluorescent material HOMO (T) and the energy level E of HOM O of the luminescent material HOMO (E) satisfies the following formula (b).

[0064] E HOMO (H 1 )<E HOMO (H 2 )≤E HOMO (T)≤E HOMO (E)

[0065] Formula (b)

[0066] Furthermore, in one aspect of the present invention, the following formula (c) is satisfied.

[0067] E HOMO (H 1 )<E HOMO (T)<E HOMO (H 2 )≤E HOMO (E)

[0068] Formula (c)

[0069] The energy level of the HOMO of the first host material and the energy level of the HOMO of the second host material are preferably both below -5.60eV, more preferably below -5.70eV, and further preferably below -5.75eV. The lower limits of the energy level of the HOMO of the first host material and the energy level of the HOMO of the second host material are not particularly limited, but are preferably both above -6.30eV, more preferably above -6.20eV, and further preferably above -6.15eV. Thus, it is possible to suppress the energy level of the HOMO of each host material from being too low and the driving voltage from becoming high. The energy level of the HOMO of the first host material can be selected from a range of above -6.30eV and below -5.80eV, from a range of above -6.20eV and below -5.90eV, or from a range of above -6.15eV and below -6.00eV. The energy level of the HOMO of the second host material can be selected from a range of -6.15eV to -5.60eV, from a range of -6.05eV to -5.70eV, from a range of more than -6.00eV to -5.75eV, or from a range of more than -5.90eV to -5.75eV. In addition, an energy level of less than -5.80eV or an energy level of less than -5.85eV can be used. In one aspect of the present invention, the energy level of the HOMO of the delayed fluorescent material can be selected from a range of more than -6.2eV to -5.3eV or preferably from a range of more than -6.0eV to -5.5eV. In addition, in one aspect of the present invention, the energy level of the HOMO of the light-emitting material can be selected from a range of more than -6.3eV to -4.8eV or from a range of more than -6.0eV to -5.0eV.

[0070] Regarding the LUMO energy level E of the first host material LUMO (H 1 ) and the LUMO energy level E of the second host material LUMO (H 2 ), preferably E LUMO (H 1 )-E LUMO (H 2 ) is between -0.10 eV and 0.70 eV. For example, it can be selected from a range of between -0.10 eV and 0.40 eV, a range of between -0.10 eV and 0.25 eV, or a range of between -0.10 eV and 0.10 eV. In one aspect of the present invention, E LUMO (H 1 )<E LUMO (H 2). In one aspect of the present invention, E LUMO (H 1 )>E LUMO (H 2 ). In one aspect of the present invention, the energy level of LUMO of the first host material and the second host material is below -2.58 eV. The lower limit value can be selected from, for example, a range exceeding -3.35 eV, a range exceeding -3.00 eV, or a range exceeding -2.75 eV. In addition, "LUMO" is an abbreviation for Lowest Unoccupied Molecular Orbital, and can be obtained by atmospheric photoelectron spectroscopy (AC-3 manufactured by RIKEN KEIKI CO., LTD., etc.).

[0071] In a preferred aspect of the present invention, E HOMO (T)-E HOMO (H 1 ) is selected from the range of -0.10 eV to 0.10 eV, E LUMO (H 1 )-E LUMO (H 2 ) is selected from the range of -0.10 eV to 0.10 eV, E HOMO (H 2 )-E HOMO (H 1 ) is selected from a range of more than 0 eV and less than 0.40 eV (for example, selected from any one of a range of more than 0 eV and less than 0.15 eV, a range of more than 0.15 eV and less than 0.25 eV, and a range of more than 0.25 eV and less than 0.40 eV). In a preferred aspect, further, the energy level E of the HOMO of the first host material is HOMO (H 1 ) is selected from the range of -6.15 eV to -6.00 eV, and the HOMO energy level E of the second host material is HOMO (H 2 ) is selected from the range of -6.05 eV to -5.70 eV (more preferably greater than -5.90 eV and less than -5.75 eV).

[0072] The first host material, the second host material, the delayed fluorescent material, and the light-emitting material contained in the light-emitting layer preferably satisfy the following formula (d).

[0073] E S1 (H1), E S1 (H2)>E S1 (T)>E S1 (E) Formula (d)

[0074] E in formula (d) S1 (H1) represents the lowest excited singlet energy of the first host material, E S1 (H2) represents the lowest excited singlet energy of the second host material, E S1 (T) represents the lowest excited singlet energy of the delayed fluorescent material, E S1 (E) represents the lowest excited singlet energy of the luminescent material. In this article, eV is used as the unit. The lowest excited singlet energy can be determined by preparing a thin film or toluene solution (concentration 10 -5 mol / L) and measured the fluorescence spectrum at room temperature (300K) to determine (for details, refer to the method for measuring the lowest excited singlet energy in the description column of the delayed fluorescent material).

[0075] As shown in formula (d), the lowest excited singlet energy of the first host material and the lowest excited singlet energy of the second host material are higher than the lowest excited singlet energy of the delayed fluorescent material, and the lowest excited singlet energy of the delayed fluorescent material is preferably higher than the lowest excited singlet energy of the luminescent material. The relationship between the lowest excited singlet energy of the first host material and the second host material is not particularly limited. In other words, the lowest excited singlet energy of the second host material can be smaller or larger than the lowest excited singlet energy of the first host material, or it can be the same as the lowest excited singlet energy of the first host material. S1 (H1)-E S1 (T) For example, it can be set in the range of 0.20 eV or more, in the range of 0.40 eV or more, or in the range of 0.60 eV or more, and can be set in the range of 1.50 eV or less, in the range of 1.20 eV or less, or in the range of 0.80 eV or less. S1 (H2)-E S1 (T) For example, it can be set in the range of 0.20 eV or more, in the range of 0.40 eV or more, or in the range of 0.60 eV or more, and can be set in the range of 1.50 eV or less, in the range of 1.20 eV or less, or in the range of 0.80 eV or less. S1 (T)-E S1 (E) For example, it can be set in the range of 0.05 eV or more, in the range of 0.10 eV or more, or in the range of 0.15 eV or more, and can be set in the range of 0.50 eV or less, in the range of 0.30 eV or less, or in the range of 0.20 eV or less. S1 (H1)-E S1(E) For example, it can be set in the range of 0.25 eV or more, in the range of 0.45 eV or more, or in the range of 0.65 eV or more, and can be set in the range of 2.00 eV or less, in the range of 1.70 eV or less, or in the range of 1.30 eV or less. S1 (H2)-E S1 (E) For example, it can be set in the range of 0.25 eV or more, in the range of 0.45 eV or more, or in the range of 0.65 eV or more, and can be set in the range of 2.00 eV or less, in the range of 1.70 eV or less, or in the range of 1.30 eV or less.

[0076] In the composition contained in the organic light-emitting element of the present invention, the concentration of the first host material is preferably 10% by weight or more, can be set in the range of 15% by weight or more, or in the range of 20% by weight or more, and is preferably 70% by weight or less, can be set in the range of 50% by weight or less, or in the range of 30% by weight or less. The concentration of the second host material is preferably 10% by weight or more, can be set in the range of 20% by weight or more, or in the range of 30% by weight or more, and is preferably 70% by weight or less, can be set in the range of 60% by weight or less, or in the range of 50% by weight or less. The concentration of the delayed fluorescent material is preferably 10% by weight or more, can be set in the range of 20% by weight or more, or in the range of 30% by weight or more, and is preferably 70% by weight or less, can be set in the range of 60% by weight or less, or in the range of 50% by weight or less. The concentration of the luminescent material is preferably above 0.01 wt%, can be set in the range of above 0.1 wt% or in the range of above 0.3 wt%, and is preferably below 20 wt%, can be set in the range of below 10 wt%, in the range of below 3 wt% or in the range of below 1 wt%.

[0077] The concentration of the first host material in the composition is preferably in the range of 0.3 to 3.0 times the concentration of the second host material. In one aspect of the present invention, the concentration of the second host material is higher than the concentration of the first host material. In one aspect of the present invention, in the composition, the concentration of the second host material is the highest. In one aspect of the present invention, in the composition, the concentration of the delayed fluorescent material is the highest. In one aspect of the present invention, the concentration of the first host material is higher than the concentration of the second host material. In one aspect of the present invention, in the composition, the concentration of the first host material is the highest. In a preferred aspect of the present invention, the combined concentration of the first host material and the second host material is preferably 40% by weight or more, more preferably more than 50% by weight, and preferably 80% by weight or less, more preferably 65% ​​by weight or less.

[0078] The total concentration of the first host material and the second host material is preferably in the range of 0.5 to 5 times the concentration of the delayed fluorescent material, and more preferably in the range of 0.65 to 2 times. For example, it can also be set in the range of 0.65 to 0.95 times or in the range of 1.2 to 1.8 times. The concentration of the delayed fluorescent material is preferably in the range of 1.5 to 500 times the concentration of the luminescent material, and more preferably in the range of 20 to 200 times, and for example, it can also be in the range of 60 to 130 times.

[0079] The composition used in the organic light-emitting element of the present invention is, for example, used as a composition constituting the light-emitting layer of an organic electroluminescent element. In addition, the composition can be a solution obtained by dissolving in a solvent, preferably using an organic solvent as the solvent at this time. The organic solvent is selected from solvents that can dissolve the first host material, the second host material, the delayed fluorescent material and the light-emitting material, and can appropriately select and adopt commonly used polar solvents or aromatic solvents. In addition, the concentration range of the above-mentioned components in the solution means the concentration of each component in all dissolved substances after removing the solvent.

[0080] In the organic light-emitting element of the present invention, the largest component of the light emission from the element is the fluorescence from the light-emitting material. In the present invention, "light emission from the element" means the light emitted from the element when the element is driven at 20°C. For example, as for the light emission from the organic light-emitting element, as long as the largest component of the light emission from the element is the fluorescence from the light-emitting material, it may include phosphorescence from the light-emitting material, light emission from the first host material or the second host material, and delayed fluorescence material, but these lights are preferably less than the fluorescence from the light-emitting material. In the present invention, more than 70% of the light emission from the element can be fluorescence from the light-emitting material, more than 90% can be fluorescence from the light-emitting material, and more than 99% can be fluorescence from the fluorescent material.

[0081] The composition used in the organic light-emitting element of the present invention preferably does not contain any metal element other than boron. In addition, a light-emitting layer that does not contain a metal element containing boron may also be used. For example, the light-emitting layer can be composed only of a compound consisting of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms, oxygen atoms, sulfur atoms, fluorine atoms and boron atoms. For example, the light-emitting layer can be composed only of a compound consisting of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms, oxygen atoms, sulfur atoms, fluorine atoms and boron atoms. For example, the light-emitting layer can be composed only of a compound consisting of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms, oxygen atoms and sulfur atoms. For example, the light-emitting layer can be composed only of a compound consisting of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms, oxygen atoms and sulfur atoms. For example, the light-emitting layer can be composed only of a compound consisting of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms and oxygen atoms.

[0082] The first host material, the second host material, the delayed fluorescent material, and the light-emitting material used in the present invention are described in detail below.

[0083] (First main material and second main material)

[0084] The first host material used in the composition of the organic light-emitting element of the present invention is a host material having a HOMO energy level lower than that of the second host material. The second host material used in the composition of the organic light-emitting element of the present invention is a host material that satisfies the relationship of the above formula (a). The second host material can be selected from compounds having the same HOMO energy level as the delayed fluorescence material or the luminescent material, or can be selected from compounds having a HOMO energy level lower than that of the delayed fluorescence material or the luminescent material. Furthermore, among the first host material and the second host material, it is preferred to select a compound having a minimum excited singlet energy greater than that of the delayed fluorescence material or the luminescent material from among the compounds having the HOMO energy level as described above.

[0085] The first host material and the second host material preferably have the function of confining the energy of the luminescent material in the compound. Thus, the luminescent material can efficiently convert the energy generated by the recombination of holes and electrons in the molecule and the energy received from the first host material, the second host material and the delayed fluorescent material into luminescence.

[0086] The first host material and the second host material are preferably organic compounds having hole transport capability and electron transport capability, preventing the long wavelength of luminescence, and having a high glass transition temperature. In addition, in a preferred aspect of the present invention, the first host material and the second host material are selected from compounds that do not radiate delayed fluorescence. The luminescence from the first host material and the second host material is preferably less than 1% of the luminescence from the organic electroluminescent element of the present invention, more preferably less than 0.1%, for example, less than 0.01% and below the detection limit.

[0087] The first host material and the second host material preferably do not contain metal atoms. For example, as the first host material and the second host material, a compound consisting of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms, oxygen atoms and sulfur atoms can be selected. For example, as the first host material and the second host material, a compound consisting of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms and oxygen atoms can be selected. For example, as the first host material and the second host material, a compound consisting of carbon atoms, hydrogen atoms and nitrogen atoms can be selected.

[0088] Examples of preferred compounds that can be used as the first host material and the second host material include compounds represented by the following general formulae (1) to (3).

[0089] [Chemical formula 4]

[0090] General formula (1)

[0091]

[0092] In the general formula (1), X represents O, S or N (R 6 ), R 1 ~R 5 Each independently represents a deuterium atom or a substituent, R 6 represents a deuterium atom, an alkyl group, an aryl group, or a group composed of an alkyl group and an aryl group. n1 and n2 each independently represent an integer of 0 to 5, n3 represents an integer of 0 to 4, n4 represents an integer of 0 to 2, and n5 represents an integer of 0 to 4. R 1 ~R 5 When n1 to n5 are each independently 2 or more, the plurality of R 1 , multiple R 2 , multiple R 3 , multiple R 4 , multiple R 5 can be the same as or different from each other. 1 , two adjacent R 2 , two adjacent R 3 , two adjacent R 4 , two adjacent R 5 They may be bonded to each other to form a ring structure. In one aspect of the present invention, the host material represented by the general formula (1) satisfies at least one of the following conditions (a) or (b).

[0093] (a) There is an acceptor group with a Hammett's σp value of 0.5 or more as R 1 or R 2 .

[0094] (b) X is O or S.

[0095] R in the general formula (1) 1 ~R 5 The substituents that can be used are preferably alkyl groups, aryl groups, or groups composed of alkyl groups and aryl groups. 1 ~R 5 and R 6 At least one hydrogen atom in the alkyl group or aryl group in the formula (R) may be substituted with a deuterium atom or a substituent, or may be unsubstituted. 1 and R 2 The acceptor group may have a Hammett's σp value of 0.5 or more.

[0096] Among them, "Hamiett's σp value" is proposed by LP Hammett, which is a value that quantifies the effect of a substituent on the reaction rate or equilibrium of a para-substituted benzene derivative. Specifically, it is the following formula established between the substituent in the para-substituted benzene derivative and the reaction rate constant or equilibrium constant:

[0097] log(k / k 0 )=ρσp

[0098] or

[0099] log(K / K 0 )=ρσp

[0100] The constant (σp) specific to the substituent in the above formula, k 0 represents the rate constant of the benzene derivative without a substituent, k represents the rate constant of the benzene derivative substituted with a substituent, K 0 represents the equilibrium constant of a benzene derivative having no substituent, K represents the equilibrium constant of a benzene derivative substituted with a substituent, and ρ represents a reaction constant determined by the type and conditions of the reaction. For the description of the "Hamiett's σp value" in the present invention and the number of each substituent, reference can be made to the description of the σp value mentioned in Hansch, C. et.al., Chem. Rev., 91, 165-195 (1991).

[0101] R 1 and R 2 The acceptor group having a Hammett's σp value of 0.5 or more is preferably a group containing a cyano group such as a cyano group or a cyanoaryl group. The cyanoaryl group is preferably a cyanophenyl group. The number of cyano groups in the cyanophenyl group may be 1 or 2 to 5. The cyanophenyl group is preferably a cyanophenyl group having a cyano group at least at the 4th position.

[0102] In the two adjacent R 1 , two adjacent R 2 , two adjacent R 3 , two adjacent R 4 , two adjacent R 5When being bonded to each other and forming cyclic structure, the cyclic structure can be an aromatic ring, can also be an aliphatic ring, and can also be a ring comprising heteroatoms, and the cyclic structure can also be a condensed ring of more than 2 rings. As heteroatoms described herein, it is preferably selected from the heteroatoms in the group consisting of nitrogen-atoms, oxygen atoms and sulphur atoms. The example of the cyclic structure formed can include benzene ring, naphthalene ring, pyridine ring, pyridazine ring, pyrimidine ring, pyrazine ring, pyrrole ring, imidazole ring, pyrazole ring, imidazoline ring, oxazole ring, isoxazole ring, thiazole ring, isothiazole ring, cyclohexadiene ring, cyclohexene ring, cyclopentene ring, cycloheptatriene ring, cycloheptadiene ring, cycloheptene ring, furan ring, thiophene ring, naphthyridine ring, quinoxaline ring, quinoline ring etc. For example, a cyclic structure formed by the condensation of multiple rings such as benzofuran structure, benzothiophene structure, phenanthro structure or tribenzo (Tripheno) structure can be formed.

[0103] [Chemical formula 5]

[0104] General formula (2)

[0105]

[0106] In the general formula (2), R 11 ~R 13 Each independently represents a deuterium atom or a substituent. n11 to n12 each independently represents an integer of 0 to 5, and n13 represents an integer of 1 to 5. 11 ~R 13 When n11 to n13 are each independently 2 or more, the plurality of R 11 , multiple R 12 , multiple R 13 They can be the same or different. 11 , two adjacent R 12 , two adjacent R 13 can bond to each other to form a ring structure. 13 When the two groups are bonded to each other to form a benzofurano structure or a benzothiopheno structure, there is a group containing a dibenzofurano structure or a dibenzothiophene structure or a group containing a cyano group as R 13 .

[0107] R 11 ~R 13 The substituents that can be used are preferably alkyl, aryl or a combination of alkyl and aryl. At least one hydrogen atom in the alkyl and aryl groups may be substituted with a deuterium atom or a substituent, or may be unsubstituted. 13It may be a group containing a dibenzofuran structure or a dibenzothiophene structure or a group containing a cyano group. For the preferred range and specific examples of the "group containing a cyano group", reference can be made to the above R 1 and R 2 Preferred ranges and specific examples of "groups containing a cyano group" that can be used. "Groups containing a dibenzofuran structure or a dibenzothiophene structure" means a group containing a dibenzofuran ring or a dibenzothiophene ring represented by the following formula (2a). In the following formula (2a), X represents O or S. At least one hydrogen atom in the ring may be substituted with a deuterium atom or a substituent.

[0108] [Chemical formula 6]

[0109] Formula (2a)

[0110]

[0111] Examples of the group containing a dibenzofuran structure or a dibenzothiophene structure may include a substituted or unsubstituted dibenzofuranyl group, a substituted or unsubstituted dibenzothiophene group, an aryl group in which at least one hydrogen atom is substituted by a substituted or unsubstituted dibenzofuranyl group or a substituted or unsubstituted dibenzothiophene group (e.g., a substituted or unsubstituted dibenzofuranylphenyl group, a substituted or unsubstituted dibenzothiophenephenyl group), a heteroaryl group in which at least one hydrogen atom is substituted by a substituted or unsubstituted dibenzofuranyl group or a substituted or unsubstituted dibenzothiophene group, a polycyclic heteroaryl group containing a dibenzofuran ring or a dibenzothiophene ring as part of a condensed ring, an aryl group in which at least one hydrogen atom is substituted by the polycyclic heteroaryl group, and a heteroaryl group in which at least one hydrogen atom is substituted by the polycyclic heteroaryl group. Examples of polycyclic heteroaryl groups may include heteroaryl groups having a benzofuran structure or a benzothienyl structure, and as specific examples thereof, may include substituted or unsubstituted benzofurocarbazolyl and substituted or unsubstituted benzothienylcarbazolyl. The benzofurocarbazolyl group may have a benzofurocarbazolyl structure at the 1-2 position (a side) of the carbazole ring, may have a benzofurocarbazolyl structure at the 2-3 position (b side), or may have a benzofurocarbazolyl structure at the 3-4 position (c side). The benzothienylcarbazolyl group may have a benzothienyl structure at the 1-2 position (a side) of the carbazole ring, may have a benzothienyl structure at the 2-3 position (b side), or may have a benzothienyl structure at the 3-4 position (c side). The following includes specific examples of benzofurocarbazolyl and benzothienylcarbazolyl. In the following specific examples, X represents O or S, and * represents a bonding position. At least one hydrogen atom in the ring may be substituted with a deuterium atom or a substituent.

[0112] [Chemical formula 7]

[0113]

[0114] About two adjacent R 11 , two adjacent R 12 , two adjacent R 13 The description and specific examples of the ring structure formed by bonding to each other can refer to the above two adjacent R 1 Description and specific examples of the ring structure formed by bonding with each other. 13 There is no group containing a dibenzofuran structure or a dibenzothiophene structure as R 13 When the group contains a cyano group, the two adjacent R 13 bonded to each other to form a benzofurano structure or a benzothiopheno structure. 13 The benzofurano structure or benzothieno structure is bonded to each other, so that the phenyl group of its parent skeleton and the benzofurano structure form a dibenzofuranyl group, and the phenyl group of its parent skeleton and the benzothienyl group form a dibenzothienyl group. The position of forming the benzofurano structure or the benzothieno structure can be any one of the 2-3 position and the 3-4 position of the phenyl group.

[0115] [Chemical formula 8]

[0116] General formula (3)

[0117]

[0118] In the general formula (3), R 21 represents a group containing a dibenzofuran structure, R 22 ~R 24 Each independently represents a deuterium atom or a substituent. n22 to n24 each independently represent an integer of 0 to 4. 22 ~R 24 When n22 to n24 are each independently 2 or more, the plurality of R 22 , multiple R 23 , multiple R 24 They can be the same or different. 22 , two adjacent R 23 , two adjacent R 24 can bond to each other to form a ring structure. 24 When the benzofurano structure or the benzothiopheno structure is formed by bonding to each other, it is preferred that an aryl group which may be substituted by an alkyl group exists as R 24 .

[0119] About R 21 The description, preferred range and specific examples of the group containing a dibenzofuran structure represented by can refer to the above R13 Description, preferred range and specific examples of the group containing a dibenzofuran structure that can be used. 21 Preferred are dibenzofuranyl and dibenzofuranphenyl. 22 ~R 24 The substituents that can be used are preferably alkyl groups, aryl groups, or groups composed of alkyl groups and aryl groups. At least one hydrogen atom in the alkyl group and the aryl group may be substituted with a deuterium atom or a substituent, or may be unsubstituted.

[0120] About two adjacent R 22 , two adjacent R 23 , two adjacent R 24 The description and specific examples of the ring structure formed by bonding to each other can refer to the above two adjacent R 1 etc. are bonded to each other to form a ring structure and specific examples.

[0121] As a host material having a structure other than the general formula (1) to (3), for example, a compound including a dibenzofuran structure bonded with a carbazole-9-yl group can be exemplified. Specifically, a group including a carbazole-9-yl group bonded to one benzene ring constituting dibenzofuran and a dibenzofuranyl group or a dibenzothiophenyl group on the other benzene ring (for example, a dibenzofuranyl group, a dibenzothiophenyl group, a phenyldibenzofuranyl group, a phenyldibenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylyl group) can be included.

[0122] The first host material or the second host material may have a deuterium atom in a part of its structure. For example, a compound in which a hydrogen atom bonded to a carbazole ring constituting the host material is substituted with a deuterium atom can be exemplified.

[0123] Examples of the combination of the first host material and the second host material may include a combination in which the first host material is a compound represented by general formula (3) and the second host material is a compound represented by general formula (1) or general formula (2), or a combination in which both the first host material and the second host material are compounds represented by general formula (3).

[0124] Preferred compounds that can be used as the first host material and the second host material are included below. However, the first host material and the second host material that can be used in the present invention should not be construed as being limited to these specific examples.

[0125] [Chemical formula 9-1]

[0126]

[0127] [Chemical formula 9-2]

[0128]

[0129] [Chemical formula 9-3]

[0130]

[0131] Compounds H30 to H58 are exemplified herein in which all hydrogen atoms of compounds H1 to H29 are replaced with deuterium atoms. Compounds H59 to H86 are exemplified herein in which all hydrogen atoms bonded to the carbazole ring and the ring condensed with the carbazole ring of compounds H1 to H17 and H19 to H29 are replaced with deuterium atoms.

[0132] A specific example of the combination of the first host material and the second host material may include a combination of compound H1 and a compound selected from the group consisting of compounds H2 to H29, H31 to H58, and H60 to H86. In addition, it may be a combination of two compounds selected from the group consisting of compounds H2 to H29, H31 to H58, and H60 to H86. For example, it may include a combination of compound H4 and a compound selected from the group consisting of compounds H2, H3, H5 to H29, H31, H32, H34 to H58, H60, H61, and H63 to H86.

[0133] (Delayed fluorescence material)

[0134] The composition contained in the organic light-emitting element of the present invention contains a delayed fluorescence material. The "delayed fluorescence material" in the present invention is an organic compound that generates reverse intersystem crossing from an excited triplet state to an excited singlet state in an excited state, and radiates fluorescence (delayed fluorescence) when returning from the excited singlet state to the ground state. In the present invention, when the luminescence lifetime is measured by a fluorescence lifetime measurement system (such as a streak camera system manufactured by Hamamatsu Photonics KK), a material in which fluorescence with a luminescence lifetime of more than 100ns (nanoseconds) is observed is called a delayed fluorescence material. The delayed fluorescence material is a material that can radiate delayed fluorescence, but when used in the organic light-emitting element of the present invention, it is not necessary to radiate delayed fluorescence from the delayed fluorescence material. The luminescence from the delayed fluorescence material is preferably less than 10% of the luminescence from the organic light-emitting element of the present invention, for example, it can be less than 1%, less than 0.1%, less than 0.01% and below the detection limit.

[0135] In the organic light-emitting element of the present invention, the delayed fluorescent material receives energy from the first host material or the second host material in the singlet excited state and transitions to the singlet excited state. In addition, the delayed fluorescent material may also receive energy from the first host material or the second host material in the triplet excited state and transition to the triplet excited state. The delayed fluorescent material has a difference between the energy of the singlet excited state and the energy of the triplet excited state (ΔE ST) is small, so the delayed fluorescent material in the triplet excited state easily reverses the intersystem crossing to the delayed fluorescent material in the singlet excited state. The delayed fluorescent material in the singlet excited state generated through these pathways provides energy to the luminescent material to make the luminescent material transition to the singlet excited state.

[0136] The difference between the lowest excited singlet energy of the delayed fluorescent material and the lowest excited triplet energy at 77K, ΔE ST It is preferably 0.3 eV or less, more preferably 0.25 eV or less, more preferably 0.2 eV or less, more preferably 0.15 eV or less, further preferably 0.1 eV or less, further preferably 0.07 eV or less, further preferably 0.05 eV or less, further preferably 0.03 eV or less, and particularly preferably 0.01 eV or less.

[0137] If ΔE ST If the device has a small size, it is easy to reverse intersystem crossing from the excited singlet state to the excited triplet state by absorbing thermal energy, so the delayed fluorescent material functions as a thermally activated delayed fluorescent material. The thermally activated delayed fluorescent material can absorb the heat emitted by the device and relatively easily reverse intersystem crossing from the excited triplet state to the excited singlet state, and the excited triplet energy efficiently contributes to luminescence.

[0138] The lowest excited singlet energy (E S1 ) and the lowest excited triplet state energy (E T1 ) is the value obtained by the following steps. ST By calculating E S1 -E T1 The value found.

[0139] (1) The lowest excited singlet energy (E S1 )

[0140] Prepare a thin film or toluene solution (concentration 10 -5 mol / L) as a sample. The fluorescence spectrum of the sample is measured at room temperature (300K). In the fluorescence spectrum, the vertical axis is set to luminescence and the horizontal axis is set to wavelength. A tangent is drawn relative to the rise of the short-wavelength side of the luminescence spectrum, and the wavelength value λedge[nm] of the intersection of the tangent and the horizontal axis is calculated. The value obtained by converting the wavelength value into an energy value using the conversion formula shown below is set as E S1 .

[0141] Conversion formula: E S1 [eV] = 1239.85 / λedge

[0142] The emission spectra in the examples described below were measured using an LED light source (M300L4 manufactured by Thorlabs Japan Inc.) as an excitation light source and a detector (PMA-12 multichannel spectrometer C10027-01 manufactured by Hamamatsu Photonics KK).

[0143] (2) The lowest excited triplet energy (E T1 )

[0144] will be compared with the lowest excited singlet state energy (E S1 ) is cooled to 77[K] by liquid nitrogen, and the sample for phosphorescence measurement is irradiated with excitation light (300nm), and the phosphorescence is measured using a detector. The luminescence 100 milliseconds after irradiation with the excitation light is set as the phosphorescence spectrum. A tangent is drawn relative to the rise on the short-wavelength side of the phosphorescence spectrum, and the wavelength value λedge[nm] of the intersection of the tangent and the horizontal axis is calculated. The value obtained by converting the wavelength value into an energy value using the conversion formula shown below is set as E T1 .

[0145] Conversion formula: E T1 [eV] = 1239.85 / λedge

[0146] The tangent line relative to the rise of the short wavelength side of the phosphorescence spectrum is drawn as follows. When moving from the short wavelength side of the phosphorescence spectrum to the maximum value on the shortest wavelength side among the maximum values ​​of the spectrum on the spectrum curve, the tangent line at each point on the curve toward the long wavelength side is considered. As the curve rises (that is, as the vertical axis increases), the slope of the tangent line increases. The tangent line drawn at the point where the value of the slope takes a maximum value is set as the tangent line relative to the rise of the short wavelength side of the phosphorescence spectrum.

[0147] In addition, the maximum point with a peak intensity of less than 10% of the maximum peak intensity of the spectrum does not include the maximum value on the above-mentioned shortest wavelength side, and the tangent drawn at the point closest to the maximum value on the shortest wavelength side and where the slope value takes the maximum value is set as a rising tangent relative to the short wavelength side of the phosphorescence spectrum.

[0148] The delayed fluorescent material used in the present invention satisfies the relationship of the above formula (a). The delayed fluorescent material used in the present invention preferably has a lower minimum excited singlet energy than the first host material or the second host material and a higher minimum excited singlet energy than the luminescent material.

[0149] The delayed fluorescent material used in the present invention preferably does not contain metal atoms. For example, as a delayed fluorescent material, a compound consisting of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms, oxygen atoms and sulfur atoms can be selected. For example, as a delayed fluorescent material, a compound consisting of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms and oxygen atoms can be selected. For example, as a delayed fluorescent material, a compound consisting of carbon atoms, hydrogen atoms and nitrogen atoms can be selected.

[0150] Typical delayed fluorescent materials may include compounds having a structure in which 1 to 2 cyano groups and at least one donor group are bonded to a benzene ring. As the donor group, for example, a substituted or unsubstituted carbazole-9-yl group may be preferably exemplified. For example, a compound in which a substituted or unsubstituted carbazole-9-yl group is bonded to three or more of the benzene rings, or a compound in which each 5-membered ring portion 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, a substituted or unsubstituted silanthene ring is fused to at least one of the two benzene rings constituting the carbazole-9-yl group, etc. Specific examples of the group having a structure in which a substituted or unsubstituted benzofuran ring is fused to a benzene ring constituting the carbazole-9-yl group may include a substituted or unsubstituted 5H-benzofurano[3,2-c]carbazole-5-yl group.

[0151] As the delayed fluorescent material, a compound represented by the following general formula (4) and emitting delayed fluorescence can be preferably used.

[0152] General formula (4)

[0153] [Chemical formula 10]

[0154]

[0155] In the general formula (4), X 1 ~X 5 represents N or CR. R represents a hydrogen atom, a deuterium atom or a substituent. 1 ~X 5 When two or more of X represent CR, these CRs may be the same as or different from each other. 1 ~X 5 At least one of X is CD (D in this case represents a donor group). 1 ~X 5 When they are all CR, Z represents an acceptor group.

[0156] Among the compounds represented by the general formula (4), the compounds are preferably substituted benzonitrile compounds, and the compounds represented by the following general formula (5) are preferred.

[0157] General formula (5)

[0158] [Chemical formula 11]

[0159]

[0160] In the general formula (5), X 1 ~X 5 represents N or CR. R represents a hydrogen atom, a deuterium atom or a substituent. 1 ~X 5 When two or more of X represent CR, these CRs may be the same as or different from each other. 1 ~X 5 At least one of them is CD (D herein represents a donor group).

[0161] In a preferred aspect of the present invention, X 1 ~X 5 In other words, it is a compound having a structure in which 1 to 2 cyano groups and at least one donor group are bonded to a benzene ring. In another preferred aspect of the present invention, only X 2 represents C-CN, X 1 , X 3 ~X 5 In other words, it is a compound having a structure in which at least one donor group is bonded to the benzene ring of isophthalonitrile. In another aspect of the present invention, only X 3 represents C-CN, X 1 , X 2 , X 4 , X 5 It 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.

[0162] The acceptor group represented by Z in the general formula (4) is a group having the property of attracting electrons to the ring bonded to Z, and can be selected from groups having positive Hammett's σp values, for example. The donor group represented by D in the general formula (4) and the general formula (5) is a group having the property of donating electrons to the ring bonded to D, and can be selected from groups having negative Hammett's σp values, for example. Hereinafter, the acceptor group may be referred to as A.

[0163] Among them, "Hamiett's σp value" is proposed by LP Hammett, which is a value that quantifies the effect of a substituent on the reaction rate or equilibrium of a para-substituted benzene derivative. Specifically, it is the following formula established between the substituent in the para-substituted benzene derivative and the reaction rate constant or equilibrium constant:

[0164] log(k / k0 )=ρσp

[0165] or

[0166] log(K / K 0 )=ρσp

[0167] In the above formula, k represents the rate constant of the benzene derivative without substituents, k 0 represents the rate constant of the benzene derivative substituted with a substituent, K represents the equilibrium constant of the benzene derivative without a substituent, and K 0 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. Regarding the description of the "Hamiett's σp value" in the present invention and the number of each substituent, reference can be made to the description of the σp value mentioned in Hansch, C. et.al., Chem. Rev., 91, 165-195 (1991).

[0168] As specific examples of the acceptor group, cyano or the acceptor group preferred as A in the general formulae (15) to (17) described below can be referred to. Also, as specific examples of the donor group, the donor group preferred as D in the general formulae (15) to (17) described below can be referred to.

[0169] In the general formula (4) and the general formula (5), X 1 ~X 5 Indicates N or CR, but at least one is CD. X 1 ~X 5 The number of N in the example is 0 to 4. For example, X 1 and X 3 and X 5 , 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 only 1 , X only 2 , X only 3 For N. X 1 ~X 5 The number of CDs in 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 1and 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 only 1 , X only 2 , X only 3 For CD. X 1 ~X 5 At least one of the above may be CA. A herein represents an acceptor group. 1 ~X 5 The number of CA in is preferably 0 to 2, and more preferably 0 or 1. A in CA may preferably include a heterocyclic aromatic group having a cyano group and an unsaturated nitrogen atom. 1 ~X 5 They can be CD or CA respectively and independently.

[0170] In X 1 ~X 5When two adjacent Rs in represent CR, two Rs can be bonded to each other to form a cyclic structure. The cyclic structure formed by bonding to each other can be an aromatic ring, or an aliphatic ring, and can also contain heteroatoms, and the cyclic structure can also be a condensed ring of more than 2 rings. As the heteroatoms described herein, it is preferably a heteroatom selected from the group consisting of nitrogen atoms, oxygen atoms and sulfur atoms. The example of the cyclic structure formed can 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 cyclopentene ring, a cycloheptatriene ring, a cycloheptadiene ring, a cycloheptene ring, a furan ring, a thiophene ring, a naphthyridine ring, a quinoxaline ring, a quinoline ring, etc. For example, a ring formed by the condensation of multiple rings such as a phenanthrene ring or a triphenylene ring can be formed.

[0171] 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), for example.

[0172] General formula (6)

[0173] [Chemical formula 12]

[0174]

[0175] In the general formula (6), R 11 and R 12 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. 11 and R 12 They can be bonded 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 of the arylene group or heteroarylene group that can be introduced into L can be a group represented by the general formula (4) or the general formula (5), or a group represented by the general formulas (6) to (9) described later. The groups represented by these general formulas (4) to (9) can be introduced up to the maximum number of substituents that can be introduced into L. Furthermore, when multiple groups represented by the general formulas (4) to (9) are introduced, these substituents can be the same as or different from each other. * represents the bonding position to the carbon atom (C) of the ring skeleton constituting the ring in the general formula (4) or the general formula (5).

[0176] In this article, "alkyl" can be any one of straight chain, branched chain, and cyclic. In addition, two or more of the straight chain part, cyclic part, and branched chain part can be mixed. The number of carbon atoms of the alkyl group can be set to, for example, more than 1, more than 2, or more than 4. In addition, the number of carbon atoms can be set to less than 30, less than 20, less than 10, less than 6, or less than 4. Specific examples of alkyl groups can include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, n-hexyl, isohexyl, 2-ethylhexyl, n-heptyl, isoheptyl, n-octyl, isooctyl, n-nonyl, isononyl, n-decyl, isodecyl, cyclopentyl, cyclohexyl, and cycloheptyl. The alkyl group of the substituent can be further substituted by an aryl group.

[0177] "Alkenyl" can be any of straight chain, branched chain, and cyclic. Furthermore, two or more of the straight chain part, cyclic part, and branched chain part can be mixed. The number of carbon atoms of the alkenyl group can be set to 2 or more, 4 or more, for example. Furthermore, the number of carbon atoms can be set to 30 or less, 20 or less, 10 or less, 6 or less, or 4 or less. Specific examples of alkenyl groups can include vinyl, n-propenyl, isopropenyl, n-butenyl, isobutenyl, n-pentenyl, isopentenyl, n-hexenyl, isohexenyl, and 2-ethylhexenyl. The alkenyl group of the substituent group can be further substituted by a substituent group.

[0178] "Aryl" and "heteroaryl" may be a monocyclic ring or a condensed ring formed by the condensation of two or more rings. In the case of a condensed ring, the number of condensed rings is preferably 2 to 6, for example, it can be selected from 2 to 4. Specific examples of rings may include a benzene ring, a pyridine ring, a pyrimidine ring, a triazine ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, a triphenylene ring, a quinoline ring, a pyrazine ring, a quinoxaline ring, and a naphthyridine ring. Specific examples of aryl or heteroaryl may include phenyl, 1-naphthyl, 2-naphthyl, 1-anthryl, 2-anthryl, 9-anthryl, 2-pyridyl, 3-pyridyl, and 4-pyridyl. "Arylene" and "heteroaryl" can be set by replacing the valence in the description of aryl and heteroaryl from 1 to 2.

[0179] The substituent means a monovalent group that can replace a hydrogen atom, and does not include the concept of a condensed group. For the description and preferred range of the substituent, reference can be made to the description and preferred range of the substituent in the general formula (10) described later.

[0180] The compound represented by the general formula (6) is preferably a compound represented by any one of the following general formulas (7) to (9).

[0181] General formula (7)

[0182] [Chemical formula 13]

[0183]

[0184] General formula (8)

[0185] [Chemical formula 14]

[0186]

[0187] General formula (9)

[0188] [Chemical formula 15]

[0189]

[0190] In the general formulas (7) to (9), R 51 ~R 60 , R 61 ~R 68 , R 71 ~R 78 Each independently represents a hydrogen atom, a deuterium atom or a substituent. For the description and preferred range of the substituents described here, reference can be made to the description and preferred range of the substituents in the general formula (10) described later. 51 ~R 60 , R 61 ~R 68 , R 71 ~R 78 It is also preferred that each of the above general formulae (7) to (9) is independently represented by any one of the groups. The number of substituents in the general formulae (7) to (9) is not particularly limited. It is also preferred that none of them is substituted (i.e., a hydrogen atom or a deuterium atom). Furthermore, when there are two or more substituents in each of the general formulae (7) to (9), these substituents may be the same or different. When there are substituents in the general formulae (7) to (9), if it is the general formula (7), then the substituent is preferably R 52 ~R 59 If any of the above is of the general formula (8), then its substituent is preferably R 62 ~R 67 If any of the above is the general formula (9), then its substituent is preferably R 72 ~R 77 Any one of .

[0191] In the general formula (9), X represents a divalent oxygen atom, a sulfur atom, a substituted or unsubstituted nitrogen atom, a substituted or unsubstituted carbon atom, a substituted or unsubstituted silicon atom, a carbonyl group, or a divalent substituted or unsubstituted vinyl group, a substituted or unsubstituted vinylene group, a substituted or unsubstituted o-arylene group, or a substituted or unsubstituted o-heteroarylene group, with a bonding chain length of 2 atoms. For specific examples and preferred ranges of substituents, reference can be made to the description of substituents in the general formulas (4) and (5).

[0192] In general formulas (7) to (9), L12 ~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 L, reference can be made to the description and preferred range of the arylene group or heteroarylene group represented by L. 12 ~L 14 Preferably, it is a single bond, a substituted or unsubstituted arylene group. The substituent of the arylene group or heteroarylene group described herein may be a group represented by the general formulae (4) to (9). The group represented by the general formulae (4) to (9) may be introduced into any region that can be introduced into L. 11 ~L 14 The maximum number of substituents. Furthermore, when a plurality of groups represented by the general formulae (4) to (9) are introduced, these substituents may be the same as or different from each other. * represents the bonding position to the carbon atom (C) constituting the ring skeleton in the general formula (4) or (5).

[0193] 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 78 For the description and preferred examples of the ring structure, reference can be made to X in the above general formula (4) and general formula (5). 1 ~X 5 Description and preferred examples of the ring structure in.

[0194] Among the cyclic structures, a structure 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 silanol ring is fused with at least one benzene ring in the general formulae (7) to (9) is preferred. More preferred are groups represented by the following general formulae (8a) to (8f) fused with the general formula (8).

[0195] [Chemical formula 16]

[0196]

[0197] In the general formulas (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 The description and preferred range of L 2 Description and preferred range.

[0198] In the 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 Can bond to each other and form cyclic structure.The cyclic structure formed by bonding to each other can be an aromatic ring, can be an aliphatic ring, and can also contain heteroatoms, and the cyclic structure can also be a condensed ring of more than 2 rings.As heteroatoms described herein, it is preferably a heteroatom selected from the group consisting of nitrogen atoms, oxygen atoms and sulphur atoms.The example of the cyclic structure formed can include benzene ring, naphthalene ring, pyridine ring, pyridazine ring, pyrimidine ring, pyrazine ring, pyrrole ring, imidazole ring, pyrazole ring, imidazoline ring, oxazole ring, isoxazole ring, thiazole ring, isothiazole ring, cyclohexadiene ring, cyclohexene ring, cyclopentene ring, cycloheptatriene ring, cycloheptadiene ring, cycloheptene ring, furan ring, thiophene ring, naphthyridine ring, quinoxaline ring, quinoline ring etc.For example, a ring formed by the condensation of multiple rings such as phenanthrene ring or triphenylene ring can be formed. The number of rings contained in the group represented by general formula (9) can be selected from the range of 3 to 5, or 5 to 7. The number of rings contained in the groups represented by general formulae (8a) to (8f) can be selected from the range of 5 to 7, or 5.

[0199] R 41 ~R 110 The substituents that can be used may include groups of the substituent group B, preferably unsubstituted alkyl groups having 1 to 10 carbon atoms or aryl groups having 6 to 10 carbon atoms that may be substituted with unsubstituted alkyl groups having 1 to 10 carbon atoms. In a preferred aspect of the present invention, R 41 ~R 110 is a hydrogen atom or an unsubstituted alkyl group having 1 to 10 carbon atoms. 41 ~R 110 is a hydrogen atom or an unsubstituted aryl group having 6 to 10 carbon atoms. 41 ~R 110 All are hydrogen atoms.

[0200] and R in the general formula (8a) to (8f) 41 ~R110 The carbon atoms to which the ring is bonded (carbon atoms constituting the ring skeleton) may be independently substituted with nitrogen atoms. That is, CR in the general formulae (8a) to (8f) 41 ~CR 110 Each of the nitrogen atoms may be independently substituted with N. The number of nitrogen atoms substituted in the groups represented by the general formulae (8a) to (8f) is preferably 0 to 4, and more preferably 1 to 2. In one aspect of the present invention, the number of nitrogen atoms substituted is zero. Furthermore, when two or more nitrogen atoms are substituted, the number of nitrogen atoms substituted in one ring is preferably one.

[0201] In the general formulas (8a) to (8f), X 1 ~X 6 represents an oxygen atom, a sulfur atom or NR. In one aspect of the present invention, X 1 ~X 6 In one aspect of the present invention, X 1 ~X 6 In one aspect of the present invention, X 1 ~X 6 NR. R represents a hydrogen atom or a substituent, preferably a substituent. As the substituent, a substituent selected from the following substituent group A can be exemplified. For example, a phenyl group substituted with an unsubstituted phenyl group or a group selected from the group consisting of an alkyl group or an aryl group or a combination of two or more groups can be preferably used.

[0202] In the general formulae (8a) to (8f), * represents a bonding position.

[0203] In the present invention, a compound represented by the following general formula (10) and emitting delayed fluorescence can be particularly preferably used as the delayed fluorescence material. In a preferred embodiment of the present invention, a compound represented by general formula (10) can be used as the delayed fluorescence material.

[0204] General formula (10)

[0205] [Chemical formula 17]

[0206]

[0207] In the general formula (10), R 1 ~R 5 0 to 4 of them represent cyano groups, R 1 ~R 5 At least one of them 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.

[0208] The substituted amino group described herein is preferably a substituted or unsubstituted diarylamino group, and the two aryl groups constituting the substituted or unsubstituted diarylamino group may be connected to each other. The connection may be made by a single bond (in this case, a carbazole ring is formed), or by -O-, -S-, -N(R 6 )-、-C(R 7 )(R 8 )-、-Si(R 9 )(R 10 )- and other connecting groups. 6 ~R 10 represents a hydrogen atom, a deuterium atom or a substituent, R 7 and R 8 , R 9 and R 10 They can be connected to each other to form a ring structure.

[0209] The substituted amino group may be R 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 , 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 , 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 R5 , R 1 and R 2 and R 3 and R 4 and R 5 As substituted amino etc. Cyano can also be R 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 , R 2 and R 3 and R 4 Set as cyano, etc.

[0210] R is neither cyano nor substituted amino 1 ~R 5represents a hydrogen atom, a deuterium atom or a substituent. Examples of the substituent described herein may include a hydroxyl group, a halogen atom (e.g., a fluorine atom, a chlorine atom, a bromine atom, an iodine atom), an alkyl group (e.g., having 1 to 40 carbon atoms), an alkoxy group (e.g., having 1 to 40 carbon atoms), an alkylthio group (e.g., having 1 to 40 carbon atoms), an aryl group (e.g., having 6 to 30 carbon atoms), an aryloxy group (e.g., having 6 to 30 carbon atoms), an arylthio group (e.g., having 6 to 30 carbon atoms), a heteroaryl group (e.g., having 5 to 30 ring skeleton atoms), a heteroaryloxy group (e.g., having 5 to 30 ring skeleton atoms), a heteroarylthio group The substituent group A comprises a group (e.g., a ring skeleton having 5 to 30 atoms), an acyl group (e.g., a carbon number of 1 to 40), an alkenyl group (e.g., a carbon number of 1 to 40), an alkynyl group (e.g., a carbon number of 1 to 40), an alkoxycarbonyl group (e.g., a carbon number of 1 to 40), an aryloxycarbonyl group (e.g., a carbon number of 1 to 40), a heteroaryloxycarbonyl group (e.g., a carbon number of 1 to 40), a silyl group (e.g., a trialkylsilyl group having 1 to 40 carbon atoms), a nitro group, and a group included herewith further substituted with one or more groups included herewith. Preferred examples of the substituent when the aryl group of the above-mentioned diarylamino group is substituted may include the substituents of the above-mentioned substituent group A, and may further include a cyano group and a substituted amino group.

[0211] For specific examples of the compound group and compounds included in 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 Japanese Patent Application No. 2017-119663, and paragraphs 0013 to 0026 of Japanese Patent Application No. 2017-119664, which are incorporated herein as a part of this document.

[0212] In addition, a compound represented by the following general formula (11) and emitting delayed fluorescence can 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.

[0213] General formula (11)

[0214] [Chemical formula 18]

[0215]

[0216] In the general formula (11), Y 1 , Y 2 and Y 3 Any two of them represent nitrogen atoms and the remaining one represents a methine or Y 1 , Y2 and Y 3 All of Z 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, and R 11 ~R 18 At least one of them is preferably a substituted or unsubstituted arylamino group or a substituted or unsubstituted carbazole group. The benzene ring constituting the arylamino group and the benzene ring constituting the carbazole group may be respectively connected to R 11 ~R 18 Together they form a single bond or a linking group. Furthermore, the compound represented by the general formula (11) contains at least two carbazole structures in the molecule. 1 , Z 2 Examples of the substituents that may be employed may include the substituents of Substituent Group A. Also, R 11 ~R 18 Specific examples of substituents that can be used for the arylamino group and the carbazole group include substituents of the substituent group A, cyano group, substituted arylamino group, and 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 They may be bonded to each other to form a ring structure.

[0217] Among the compounds represented by the general formula (11), the compounds represented by the general formula (12) are particularly useful.

[0218] General formula (12)

[0219] [Chemical formula 19]

[0220]

[0221] In the general formula (12), Y 1 , Y 2 and Y 3 Any two of them represent nitrogen atoms and the remaining one represents a methine or Y 1 , Y 2 and Y 3 All of Z represent nitrogen atoms. 2 represents a hydrogen atom, a deuterium atom or a substituent. 11 ~R18 and R 21 ~R 28 R each independently represents a hydrogen atom, a deuterium atom or a substituent. 11 ~R 18 At least one and / or R 21 ~R 28 At least one of them preferably represents a substituted or unsubstituted arylamino group or a substituted or unsubstituted carbazole group. The benzene ring constituting the arylamino group and the benzene ring constituting the carbazole group may be respectively connected to R 11 ~R 18 or R 21 ~R 28 Together they form a single bond or a linking group. Z 2 Examples of the substituents that may be employed may include the substituents of Substituent Group A. Also, R 11 ~R 18 , R 21 ~R 28 Specific examples of substituents that can be used for the arylamino group and the carbazole group include substituents of the substituent group A, cyano group, substituted arylamino group, and 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 28 They may be bonded to each other to form a ring structure.

[0222] For specific examples of the compound group and compounds included in the general formula (12), reference can be made to the compounds described in paragraphs 0020 to 0062 of WO2013 / 081088 or Appl. Phys. Let, 98, 083302 (2011), which are incorporated herein by reference.

[0223] Furthermore, a compound represented by the following general formula (13) and emitting delayed fluorescence can be particularly preferably used as the delayed fluorescence material of the present invention.

[0224] General formula (13)

[0225] [Chemical formula 20]

[0226]

[0227] In the 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 preferably include two acceptor groups in a meta-position relationship with each other. For example, in R 91 When it is a donor group, preferably at least R 92 and R 94 is the structure of the acceptor group and at least R 92 and R 96 is the structure of the acceptor group. The acceptor groups present in the molecule may be all the same or different from each other, but for example, all the same structure can be selected. The number of acceptor groups is preferably 2 to 3, for example, 2 can be selected. Furthermore, there may be two or more donor groups, in which case the donor groups may be all the same or different from each other. The number of donor groups is preferably 1 to 3, for example, only 1 or 2. In addition, for the description and preferred range of the donor group and the acceptor group, reference can be made to the description and preferred range of D and Z in the general formula (4). In particular, in the general formula (13), the donor group is preferably represented by the general formula (6), and the acceptor group is preferably a cyano group or represented by the following general formula (14).

[0228] General formula (14)

[0229] [Chemical formula 21]

[0230]

[0231] In the general formula (14), Y 4 ~Y 6 represents a nitrogen atom or represents a methine group, but at least one of them is a nitrogen atom, and preferably both represent nitrogen atoms. 101 ~R 110 Each independently represents a hydrogen atom, a deuterium atom or a substituent, but at least one is preferably an alkyl group. For the description and preferred range of the substituents described herein, reference can be made to the description and preferred range of the substituents in the general formula (10). 15represents 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 aspect of the present invention, L in the general formula (14) 15 is a single bond. * represents a bonding position to a carbon atom (C) constituting the ring skeleton in the general formula (13).

[0232] In another preferred embodiment of the present invention, a compound represented by the general formula (15) can be used as a delayed fluorescent material. The compound represented by the general formula (15) includes a compound represented by the general formula (15a).

[0233] General formula (15)

[0234] [Chemical formula 22]

[0235]

[0236] General formula (15a)

[0237] [Chemical formula 23]

[0238]

[0239] Among the compounds represented by the general formula (15), the compounds represented by the following general formula (16) or the compounds represented by the general formula (17) are particularly preferred.

[0240] General formula (16)

[0241] [Chemical formula 24]

[0242]

[0243] General formula (17)

[0244] [Chemical formula 25]

[0245]

[0246] In another preferred embodiment of the present invention, a compound represented by the general formula (18) can be used as a delayed fluorescent material. The compound represented by the general formula (18) includes a compound represented by the general formula (18a).

[0247] General formula (18)

[0248] [Chemical formula 26]

[0249]

[0250] In general formulae (15) to (18), D represents a donor group, A represents an acceptor group, and R represents a hydrogen atom, a deuterium atom or a substituent. The two Ds in general formula (18) may be the same or different. For the description and preferred range of the donor group and the acceptor group, reference may be made to the corresponding description and preferred range of general formula (4). As a substituent for R, an alkyl group or an aryl group which may be substituted by one or more groups selected from the group consisting of an alkyl group and an aryl group may be exemplified.

[0251] The following are specific examples of donor groups preferred as D in general formulae (15) to (17). In the following specific examples, * represents a bonding position, and "D" represents a deuterium atom. In the following specific examples, the hydrogen atom may be substituted by an alkyl group, for example. Furthermore, the substituted or unsubstituted benzene ring may be further condensed.

[0252] [Chemical formula 27-1]

[0253]

[0254] [Chemical formula 27-2]

[0255]

[0256] The following are specific examples of the acceptor group preferred as A in the general formulae (15) to (17). In the following specific examples, * represents a bonding position, and "D" represents deuterium.

[0257] [Chemical formula 28-1]

[0258]

[0259] [Chemical formula 28-2]

[0260]

[0261] The following include preferred examples of R in the general formulae (15) to (17). In the following specific examples, * represents a bonding position, and "D" represents deuterium.

[0262] [Chemical formula 29]

[0263]

[0264] Among the compounds represented by the general formula (18), the compounds represented by the following general formula (18a) are particularly preferred.

[0265] General formula (18a)

[0266] [Chemical formula 30]

[0267]

[0268] In the general formula (18a), R 201 ~R 221 R each independently represents a hydrogen atom or a substituent, and preferably represents a hydrogen atom, an alkyl group, an aryl group, or a group formed by bonding an alkyl group and an aryl group. 201 and R 202 , R 202 and R 203 , R 203 and R 204 , R 205 and R 206 , R 206 and R 207 , R 207 and R 208 , R 214 and R 215 , R 215 and R 216 , R 216 and R 217 , R 218 and R 219 , R 219 and R 220 , R 220 and R 221 At least one group of them is bonded to each other to form a benzofurano structure or a benzothiopheno structure. 201 and R 202 , R 202 and R 203 , R 203 and R 204 , R 205 and R 206 , R 206 and R 207 , R 207 and R 208 One or two groups in R 214 and R 215 , R 215 and R 216 , R 216 and R 217 , R 218 and R 219 , R 219 and R 220 , R 220 and R 221 One or two groups of R are bonded to each other to form a benzofurano structure or a benzothiopheno structure. 203 and R 204 bonded to each other to form a benzofurano structure or a benzothiopheno structure, and more preferably R 203 and R 204 , R 216 and R 217are bonded to each other to form a benzofurano structure or a benzothiopheno structure. 203 and R 204 , R 216 and R 217 Bonded to each other to form a benzofuran structure or a benzothiophene structure, R 206 and R 219 It is a substituted or unsubstituted aryl group (preferably a substituted or unsubstituted phenyl group, more preferably an unsubstituted phenyl group).

[0269] Some or all of the hydrogen atoms in the general formula (18a) may be replaced by deuterium atoms. For example, some or all of the hydrogen atoms of the two phenyl groups bonded to the triazine group may be replaced by deuterium atoms. Also, some or all of the hydrogen atoms bonded to the two carbazole groups may be replaced by deuterium atoms. Also, R 209 ~R 213 It may be a deuterium atom.

[0270] In another preferred embodiment of the present invention, a compound having a phenazine skeleton, preferably a compound having a dibenzo[a,c]phenazine skeleton can be used as a delayed fluorescent material. For example, a compound represented by the following general formula (19) can be used.

[0271] [Chemical formula 31]

[0272] General formula (19)

[0273]

[0274] In the general formula (19), R 231 ~R 242 R each independently represents a hydrogen atom or a substituent, and preferably represents a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, or a substituted or unsubstituted diarylamino group. 231 and R 232 , R 232 and R 233 , R 233 and R 234 , R 235 and R 236 , R 236 and R 237 , R 237 and R 238 , R 239 and R 240 , R 240 and R 241 , R 241 and R 242The phenyl ring may be bonded to each other to form a ring structure. Preferred ring structures are benzene rings, furan rings and thiophene rings, more preferably benzene rings. The benzene ring may be further fused with other rings and may be substituted with substituents. Substituents to the benzene ring may include deuterium atoms, cyano groups, substituted or unsubstituted alkyl groups, substituted or unsubstituted aryl groups, substituted or unsubstituted heteroaryl groups or substituted or unsubstituted diarylamino groups.

[0275] In a preferred aspect of the present invention, R 231 and R 232 Bonded to each other to form a benzene ring that can be substituted, R 233 and R 234 In a preferred aspect of the present invention, R 231 ~R 242 At least one of them is a substituent containing a diarylamino group, for example, a substituted or unsubstituted diarylamino group. The two aryl groups constituting the diarylamino structure described herein are preferably bonded to each other, more preferably one or more rings are further fused, and more preferably two rings are further fused to form a 5-ring structure.

[0276] The following include preferred compounds that can be used as delayed fluorescent materials. In the structural formulas of the following exemplary compounds, t-Bu represents a tert-butyl group.

[0277] [Chemical formula 32-1]

[0278]

[0279] [Chemical formula 32-2]

[0280]

[0281] [Chemical formula 32-3]

[0282]

[0283] [Chemical formula 32-4]

[0284]

[0285] [Chemical formula 32-5]

[0286]

[0287] [Chemical formula 32-6]

[0288]

[0289] [Chemical formula 32-7]

[0290]

[0291] [Chemical formula 32-8]

[0292]

[0293] [Chemical formula 32-9]

[0294]

[0295] [Chemical formula 32-10]

[0296]

[0297] [Chemical formula 32-11]

[0298]

[0299] [Chemical formula 32-12]

[0300]

[0301] [Chemical formula 32-13]

[0302]

[0303] [Chemical formula 32-14]

[0304]

[0305] [Chemical formula 32-15]

[0306]

[0307] [Chemical formula 32-16]

[0308]

[0309] [Chemical formula 32-17]

[0310]

[0311] [Chemical formula 32-18]

[0312]

[0313] [Chemical formula 32-19]

[0314]

[0315] In the delayed fluorescent material, in addition to the above, known delayed fluorescent materials can also be used in appropriate combination. Moreover, even unknown delayed fluorescent materials can be used. In particular, the compound represented by the general formula (4) described in paragraphs 0013 to 0042 of the specification of Japanese Patent No. 2021-188860, which is cited as part of this article, and the compound described in paragraphs 0043 to 0048 can be preferably used.

[0316] The delayed fluorescent material may include paragraphs 0008 to 0048 and 0095 to 0133 of WO2013 / 154064, paragraphs 0007 to 0047 and 0073 to 0085 of WO2013 / 011954, paragraphs 0007 to 0033 and 0059 to 0066 of WO2013 / 011955, paragraphs 0008 to 0071 of WO2013 / 081088, 0009 to 0046 and 0093 to 0134 of Japanese Patent Application Publication No. 2013-256490, 0008 to 0020 and 0038 to 0040 of Japanese Patent Application Publication No. 2013-116975, 0007 to 0032 and 0079 to 0084 of WO2013 / 133359, 000 8 to 0054 and 0101 to 0121, JP-A-2014-9352, JP-A-2014-9352, JP-A-2014-9224, JP-A-2017-119663, JP-A-2017-119664 ...3, JP-A-2017-119664, JP-A-2017-119664, JP-A-2017-119664, JP-A-2017-119663, JP-A-2017-119664, JP-A-2017-119664, JP-A-2017-119664, JP-A-2017-119663, JP- The invention relates to a material comprising a compound included in the general formula described in paragraph 6, paragraphs 0012 to 0025 of Japanese Patent Application Publication No. 2017-222623, paragraphs 0010 to 0050 of Japanese Patent Application Publication No. 2017-226838, paragraphs 0012 to 0043 of Japanese Patent Application Publication No. 2018-100411, and paragraphs 0016 to 0044 of WO2018 / 047853, and particularly an exemplary compound and radiating delayed fluorescence.Furthermore, Japanese Patent Application Publication No. 2013-253121, WO2013 / 133359, WO2014 / 034535, WO2014 / 115743, WO2014 / 122895, WO2014 / 126200, WO2014 / 136758, WO2014 / 133121, and the like may also be used. Publication No. WO2014 / 136860, Publication No. WO2014 / 196585, Publication No. WO2014 / 189122, Publication No. WO2014 / 168101, Publication No. WO2015 / 008580, Publication No. WO2014 / 203840, Publication No. WO2015 / 002213, Publication No. WO2015 / 016200, Publication No. WO201 5 / 019725, WO2015 / 072470, WO2015 / 108049, WO2015 / 080182, WO2015 / 072537, WO2015 / 080183, Japanese Patent Application No. 2015-129240, WO2015 / 129714, WO2015 / 1297 15, WO2015 / 133501, WO2015 / 136880, WO2015 / 137244, WO2015 / 137202, WO2015 / 137136, WO2015 / 146541, WO2015 / 159541 and a material emitting delayed fluorescence. In addition, the above-mentioned publications described in this paragraph are incorporated herein as part of this document.

[0317] (Luminescent material)

[0318] The composition included in the organic light-emitting element of the present invention contains a light-emitting material. The light-emitting material is a material that becomes the main light source of light emitted from the organic light-emitting element. It is preferably a fluorescent material, and may also be a delayed fluorescent material.

[0319] The light-emitting material used in the present invention can be selected from light-emitting materials having a higher HOMO energy level than the first host material and having the same HOMO energy level as the second host material or the delayed fluorescent material, or can be selected from light-emitting materials having a higher HOMO energy level than the first host material, the second host material and the delayed fluorescent material. Moreover, among the light-emitting materials, it is preferred to select a light-emitting material having a HOMO energy level as described above and having a lower lowest excited singlet energy than the first host material, the second host material and the delayed fluorescent material. Moreover, in the organic light-emitting element of the present invention, fluorescence from the light-emitting material is radiated. The light emission from the light-emitting material generally includes delayed fluorescence. The largest component of the light emission from the element is the fluorescence from the light-emitting material. That is, the light emission from the light-emitting material is the largest in the light emission from the organic light-emitting element of the present invention.

[0320] In a preferred aspect of the present invention, the luminescent material receives energy from the first host material or the second host material in an excited singlet state, the delayed fluorescent material in an excited singlet state, and the delayed fluorescent material that undergoes reverse intersystem crossing from an excited triplet state to become an excited singlet state, and transitions to the excited singlet state. And, in a more preferred aspect of the present invention, the luminescent material receives energy from the delayed fluorescent material in an excited singlet state and the delayed fluorescent material that undergoes reverse intersystem crossing from an excited triplet state to become an excited singlet state, and transitions to the excited singlet state. The excited singlet state of the generated luminescent material radiates fluorescence when it returns to the ground state later.

[0321] As a luminescent material, any fluorescent material (fluorescent compound) that satisfies the specified conditions can be used without particular limitation. Here, "fluorescent material" refers to a material whose fluorescence with a luminescence lifetime of less than 100ns (nanoseconds) is observed when the luminescence lifetime is measured by a fluorescence lifetime measurement system (such as a streak camera system manufactured by Hamamatsu Photonics KK). The luminescence from the luminescent material may include delayed fluorescence or phosphorescence, but the largest component of the luminescence from the luminescent material is fluorescence. In one aspect of the present invention, the organic light-emitting element does not radiate phosphorescence or the amount of phosphorescence radiated is less than 1% of the fluorescence.

[0322] If the conditions of the present invention are met, two or more luminescent materials may be used. For example, by using two or more luminescent materials with different luminescent colors at the same time, it is possible to emit light of a desired color. In addition, it is also possible to use a single luminescent material to emit light in a single color.

[0323] In the present invention, the maximum emission wavelength of the compound that can be used as a luminescent material is not particularly limited. Therefore, it is possible to appropriately select and use a luminescent material having a maximum emission wavelength in the visible region (380 to 780 nm), a luminescent material having a maximum emission wavelength in the infrared region (780 nm to 1 mm), or a compound having a maximum emission wavelength in the ultraviolet region (e.g., 280 to 380 nm). Preferably, it is a fluorescent material having a maximum emission wavelength in the visible region. For example, a luminescent material having a maximum emission wavelength in the region of 380 to 780 nm in the range of 380 to 570 nm can be selected, a luminescent material having a maximum emission wavelength in the range of 570 to 650 nm can be selected, a luminescent material having a maximum emission wavelength in the range of 650 to 700 nm can be selected, or a luminescent material having a maximum emission wavelength in the range of 700 to 780 nm can be selected.

[0324] In a preferred aspect of the present invention, each compound is selected and combined to overlap between the emission wavelength region of the delayed fluorescent material and the absorption wavelength region of the luminescent material. In particular, it is preferred that the edge of the short wavelength side of the emission spectrum of the delayed fluorescent material overlaps the edge of the long wavelength side of the absorption spectrum of the luminescent material.

[0325] The luminescent material preferably does not contain metal atoms other than boron atoms. For example, the luminescent material may be a compound containing both boron atoms and fluorine atoms. Furthermore, it may also be a compound containing boron atoms but not fluorine atoms. Furthermore, it may not contain metal atoms at all. For example, as a luminescent material, a compound consisting of atoms selected from the group consisting of carbon atoms, hydrogen atoms, deuterium atoms, nitrogen atoms, oxygen atoms, sulfur atoms, fluorine atoms and boron atoms can be selected. For example, as a luminescent material, a compound consisting of atoms selected from the group consisting of carbon atoms, hydrogen atoms, deuterium atoms, nitrogen atoms, oxygen atoms, fluorine atoms and boron atoms can be selected. For example, as a luminescent material, a compound consisting of atoms selected from the group consisting of carbon atoms, hydrogen atoms, deuterium atoms, nitrogen atoms, oxygen atoms, sulfur atoms and boron atoms can be selected. For example, as a luminescent material, a compound consisting of atoms selected from the group consisting of carbon atoms, hydrogen atoms, deuterium atoms, nitrogen atoms, oxygen atoms, sulfur atoms and boron atoms can be selected. For example, as a luminescent material, a compound consisting of atoms selected from the group consisting of carbon atoms, hydrogen atoms, deuterium atoms, nitrogen atoms and boron atoms can be selected. For example, as the luminescent material, 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. For example, as the luminescent material, a compound consisting of atoms selected from the group consisting of carbon atoms, hydrogen atoms, deuterium atoms, nitrogen atoms, and oxygen atoms can be selected. For example, as the luminescent material, a compound consisting of carbon atoms and hydrogen atoms can be selected.

[0326] As the luminescent material, a compound having a multiple resonance effect of a boron atom and a nitrogen atom or a compound containing a fused aromatic ring structure such as anthracene, pyrene, and perylene can be exemplified. Also, as the luminescent material, a compound containing a boron atom and a nitrogen atom showing a multiple resonance effect and having a fused ring structure having a ring number of 4 or more can be exemplified. In addition, as the luminescent material, a compound having a structure in which a pyrrole ring and two benzene rings are fused to share a nitrogen atom in a hetero 6-membered ring containing a boron atom and a nitrogen atom can also be exemplified.

[0327] In a preferred aspect of the present invention, a compound represented by the following general formula (20) is used as a light-emitting material.

[0328] General formula (20)

[0329] [Chemical formula 33]

[0330]

[0331] In the general formula (20), X 1 and X 2 One of them is a nitrogen atom and the other is a boron atom. In one aspect of the present invention, X 1 is a nitrogen atom, X 2 is a boron atom. At this time, R 17 and R 18 are bonded to each other to form a single bond to form a pyrrole ring. In another aspect of the present invention, X 1 is a boron atom, X 2 is a nitrogen atom. In this case, R 21 and R 22 They are bonded to each other to form a single bond to form a pyrrole ring.

[0332] In the general formula (20), R 1 ~R 26 , A 1 , A 2 Each independently represents a hydrogen atom, a deuterium atom or a substituent.

[0333] R 1 and R 2 , R 2 and R 3 , R 3 and R 4 , R 4 and R 5 , R 5 and R 6 , R 6 and R 7 , R 7 and R 8 , R 8 and R 9 , R 9and R 10 , R 10 and R 11 , R 11 and R 12 , R 13 and R 14 , R 14 and R 15 , R 15 and R 16 , R 16 and R 17 , R 17 and R 18 , R 18 and R 19 , R 19 and R 20 , R 20 and R 21 , R 21 and R 22 , R 22 and R 23 , R 23 and R 24 , R 24 and R 25 , R 25 and R 26 They may be bonded to each other to form a ring structure.

[0334] R 7 and R 8 The ring structure formed by bonding contains a boron atom and four carbon atoms as ring skeleton constituent atoms. 1 When it is a boron atom, R 17 and R 18 The ring structure formed by bonding contains a boron atom and four carbon atoms as ring skeleton constituent atoms. 1 When X is a nitrogen atom, the ring structure is limited to a pyrrole ring. 2 When it is a boron atom, R 21 and R 22 The ring structure formed by bonding contains a boron atom and four carbon atoms as ring skeleton constituent atoms. 2 When R is a nitrogen atom, the ring structure is limited to a pyrrole ring. 7 and R 8 , R 17 and R 18 , R 21 and R 22 When they are bonded to each other to form a cyclic structure containing a boron atom, the cyclic structure is preferably a 5- to 7-membered ring, more preferably a 5- or 6-membered ring, and even more preferably a 6-membered ring. 7 and R 8 , R 17 and R 18 , R21 and R 22 When they are bonded to each other, they are preferably bonded to each other to form a single bond, -O-, -S-, or -N(R 27 )-、-C(R 28 )(R 29 )-、-Si(R 30 )(R 31 )-、-B(R 32 )-, -CO-, -CS-, more preferably -O-, -S- or -N(R 27 )-, further preferably forming -N(R 27 )-. Among them, R 27 ~R 32 Each independently represents a hydrogen atom, a deuterium atom or a substituent. As the substituent, any group selected from the following substituent groups A to E may be used, but preferably a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group is preferred, and R is particularly preferred. 27 is a substituted or unsubstituted aryl group. 27 ~R 32 When R is a substituent, 7 and R 8 R in the ring formed by bonding to each other 27 ~R 32 Can be used with R 6 and R 9 At least one of them is bonded to further form a ring structure, R 17 and R 18 R in the ring formed by bonding to each other 27 ~R 32 Can be used with R 16 and R 19 At least one of them is bonded to further form a ring structure, R 21 and R 22 R in the ring formed by bonding to each other 27 ~R 32 Can be used with R 20 and R 23 In one aspect of the present invention, R 7 and R 8 , R 17 and R 18 , R 21 and R 22 In one aspect of the invention, R 7 and R 8 , R 17 and R 18 , R 21 and R 22In one aspect of the invention, only two groups of R 7 and R 8 , R 17 and R 18 , R 21 and R 22 are all bonded to each other.

[0335] R 1 and R 2 , R 2 and R 3 , R 3 and R 4 , R 4 and R 5 , R 5 and R 6 , R 6 and R 7 , R 8 and R 9 , R 9 and R 10 , R 10 and R 11 , R 11 and R 12 , R 13 and R 14 , R 14 and R 15 , R 15 and R 16 , R 16 and R 17 , R 18 and R 19 , R 19 and R 20 , R 20 and R 21 , R 22 and R 23 , R 23 and R 24 , R 24 and R 25 , R 25 and R 26The cyclic structure formed by bonding to each other can be an aromatic ring or an aliphatic ring, and can include heteroatoms, and other rings can be further fused with more than one ring. As heteroatoms described herein, it is preferably selected from the heteroatoms in the group consisting of nitrogen atoms, oxygen atoms and sulphur atoms. The example of the cyclic structure formed can include a benzene ring, a pyridine ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring, a pyrrole ring, an imidazole ring, a pyrazole ring, a triazole ring, an imidazoline ring, a furan ring, a thiophene ring, an oxazole ring, an isoxazole ring, a thiazole ring, an isothiazole ring, a cyclohexadiene ring, a cyclohexene ring, a cyclopentene ring, a cycloheptatriene ring, a cycloheptadiene ring, a cycloheptene ring and a ring formed by further fusion of one or more rings in the group consisting of these rings. In a preferred aspect of the present invention, the cyclic structure is a substituted or unsubstituted benzene ring (which can be further fused with a ring), for example, a benzene ring that can be substituted by an alkyl or aryl group. In a preferred aspect of the present invention, the cyclic structure is a substituted or unsubstituted heteroaromatic ring, preferably a furan ring of benzofuran or a thiophene ring of benzothiophene. 1 and R 2 , R 2 and R 3 , R 3 and R 4 , R 4 and R 5 , R 5 and R 6 , R 6 and R 7 , R 8 and R 9 , R 9 and R 10 , R 10 and R 11 , R 11 and R 12 , R 13 and R 14 , R 14 and R 15 , R 15 and R 16 , R 16 and R 17 , R 18 and R 19 , R 19 and R 20 , R 20 and R 21 , R 22 and R 23 , R 23 and R 24 , R 24 and R 25 , R 25 and R 26The number of combinations of the ring structures formed by bonding to each other in the embodiment of the present invention may be 0, for example, it may be any one of 1 to 6. For example, it may be any one of 1 to 4, and 1, 2, 3 or 4 may be selected. In one aspect of the present invention, from R 1 and R 2 , R 2 and R 3 , R 3 and R 4 One group selected from among the above is bonded to each other to form a ring structure. In one aspect of the present invention, R 5 and R 6 In one aspect of the present invention, R 9 and R 10 , R 10 and R 11 , R 11 and R 12 One group selected from among the above is bonded to each other to form a ring structure. In one aspect of the present invention, R 1 and R 2 , R 13 and R 14 In one aspect of the present invention, any of R 1 and R 2 , R 2 and R 3 , R 3 and R 4 One group selected from among the groups are bonded to each other to form a ring structure, and R 5 and R 6 In one aspect of the present invention, R 5 and R 6 , R 19 and R 20 Any of them are bonded to each other to form a ring structure.

[0336] Not adjacent to R n (n=1~26) R bonded to each other 1 ~R 26 is a hydrogen atom, a deuterium atom or a substituent. As the substituent, any one of the substituent groups A to E described below can be used.

[0337] R 1 ~R 26Preferred substituents that can be used are substituted or unsubstituted alkyl, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, for example, the substituent can be a substituted or unsubstituted aryl, for example, the substituent can be a substituted or unsubstituted alkyl. The substituents of the alkyl, aryl, and heteroaryl groups described herein can also be selected from any one of the substituent groups A to E, but are preferably selected from one or more groups consisting of alkyl, aryl, and heteroaryl groups, more preferably groups of the substituent group E, and can also be unsubstituted. In a preferred aspect of the present invention, R 1 ~R 6 At least one of them is a substituent, preferably a group of substituent group E. For example, R 1 ~R 6 At least one of them is a substituent, preferably a group of substituent group E. For example, R 5 and R 6 is a substituent, preferably a group of substituent group E. In a preferred aspect of the present invention, R 3 and R 6 At least one of them is a substituent, more preferably both are substituents, and preferably a group of substituent group E. In a preferred aspect of the present invention, in X 1 When it is a nitrogen atom, R 15 and R 20 At least one of them is a substituent, more preferably both are substituents, and preferably a group of substituent group E. In this case, R 16 and R 17 In a preferred aspect of the present invention, in X 2 When it is a nitrogen atom, R 19 and R 24 At least one of them is a substituent, more preferably both are substituents, and preferably a group of substituent group E. In this case, R 21 and R 22 In one aspect of the present invention, R 8 and R 12 At least one of is a substituent, preferably both are substituents. In one aspect of the present invention, R 8 , R 10 and R 12 As a substituent. 8 ~R 12 The substituent of X is preferably an unsubstituted alkyl group. 1 When it is a boron atom, R 13 and R 17 At least one of is a substituent, preferably both are substituents. In one aspect of the present invention, in X 1 When it is a boron atom, R 13, R 15 and R 17 is a substituent. 1 When it is a boron atom, as R 13 ~R 17 The substituent of X is preferably an unsubstituted alkyl group. 2 When it is a boron atom, R 22 and R 26 At least one of is a substituent, preferably both are substituents. In one aspect of the present invention, in X 2 When it is a boron atom, R 22 , R 24 and R 26 is a substituent. 2 When it is a boron atom, as R 22 ~R 26 The substituent is preferably an unsubstituted alkyl group.

[0338] A 1 and A 2 is a hydrogen atom, a deuterium atom or a substituent. As the substituent, any one of the substituent groups A to E described below can be used.

[0339] A 1 and A 2 A preferred substituent that can be used is an acceptor group. An acceptor group is a group having a positive Hammett's σp value. For the description of "Hamitte's σp value", reference can be made to the description of "Hamitte's σp value" described in the column (first host material and second host material) above.

[0340] A 1 and A 2The acceptor group that can be used is preferably a group with a Hammett's σp value greater than 0.2. The group with a Hammett's σp value greater than 0.2 may include a cyano group, an aryl group substituted at least with a cyano group, a group containing a fluorine atom, and a substituted or unsubstituted heteroaryl group containing a nitrogen atom as a constituent atom of the ring skeleton. The aryl group substituted at least with a cyano group described herein may be substituted with a substituent (e.g., an alkyl group or an aryl group) other than a cyano group, but may also be an aryl group substituted only with a cyano group. The aryl group substituted at least with a cyano group is preferably a phenyl group substituted at least with a cyano group. The number of substitutions of the cyano group is preferably one or two, for example, it may be one or two. The group containing a fluorine atom may include a fluorine atom, a fluorinated alkyl group, a fluorine atom or an aryl group substituted at least with a fluorinated alkyl group. The fluorinated alkyl group is preferably a perfluoroalkyl group, and the number of carbon atoms is preferably 1 to 6, more preferably 1 to 3. In addition, the heteroaryl group containing a nitrogen atom as a constituent atom of the ring skeleton may be a monocyclic ring or a condensed ring formed by condensing two or more rings. In the case of a condensed ring, the number of rings after condensation is preferably 2 to 6, for example, it can be selected from 2 to 4 or can be set to 2. Specific examples of the ring constituting the heteroaryl group may include a pyridine ring, a pyrimidine ring, a pyrazine ring, a triazine ring, a quinoline ring, an isoquinoline ring, a quinazoline ring, a quinoxaline ring, and a naphthyridine ring other than a quinazoline ring and a quinoxaline ring. The ring constituting the heteroaryl group may be substituted with a deuterium atom or a substituent, and the substituent may include, for example, one group selected from the group consisting of an alkyl group, an aryl group, and a heteroaryl group, or a group consisting of two or more groups. As A 1 and A 2 Among the acceptor groups that can be used, cyano is particularly preferred.

[0341] In one aspect of the present invention, A 1 and A 2 are independently a hydrogen atom or a deuterium atom. 1 and A 2 In one aspect of the present invention, A 1 and A 2 These two are acceptor groups. In one aspect of the present invention, A 1 and A 2 In one aspect of the present invention, A 1 and A 2 is a halogen atom, for example, a bromine atom.

[0342] Specific examples of acceptor groups that can be used in the present invention are shown below. The acceptor groups that can be used in the present invention are not limited by the following specific examples. In this article, methyl groups are omitted. Therefore, for example, if it is A15, it means a group containing two 4-methylphenyl groups. And, "D" represents a deuterium atom. * represents a bonding position.

[0343] [Chemical formula 34-1]

[0344]

[0345] [Chemical formula 34-2]

[0346]

[0347] In addition, in X 1 is a nitrogen atom, R 7 and R 8 The six-membered ring is formed by bonding via the nitrogen atom. 21 and R 22 The six-membered ring is formed by bonding via the nitrogen atom. 17 and R 18 When they are bonded to form a single bond, R 1 ~R 6 At least one of them is preferably a substituted or unsubstituted aryl group or R 1 and R 2 , R 2 and R 3 , R 3 and R 4 , R 4 and R 5 , R 5 and R 6 Any of them are bonded to each other to form an aromatic ring (a substituted or unsubstituted benzene ring which may be fused) or a heteroaromatic ring (preferably a furan ring of a substituted or unsubstituted benzofuran which may be fused, a substituted or unsubstituted thiophene ring of a benzothiophene which may be fused).

[0348] And, preferably in X 1 is a boron atom, X 2 is a nitrogen atom, R 7 and R 8 , R 17 and R 18 When the ring structure is formed by bonding to each other to form a boron atom, the ring structure is a 5- to 7-membered ring. When the ring structure is a 6-membered ring, R 7 and R 8 , R 17 and R 18 bonded to each other to form -B(R 32 )-, -CO-, -CS- or -N(R 27 )-.

[0349] In the general formula (20), X 1 When X is a nitrogen atom, the compound of the present invention has the following skeleton (20a). 2 When is a nitrogen atom, the compound of the present invention has the following skeleton (20b).

[0350] [Chemical formula 35]

[0351]

[0352] Each hydrogen atom in the skeleton (20a) and the skeleton (20b) may be substituted with a deuterium atom or a substituent. Furthermore, the adjacent hydrogen atoms may be substituted with a linking group to form a ring structure. For details, reference may be made to the corresponding R of the general formula (20). 1 ~R 26 , A 1 , A 2 . Examples include compounds in which the phenyl groups bonded to the boron atom in the skeleton (20a) and the skeleton (20b) are all substituted with mesityl, 2,6-diisopropylphenyl or 2,4,6-triisopropylphenyl. In one aspect of the present invention, each hydrogen atom in the skeleton (20a) and the skeleton (20b) may not be substituted with a linking group together with adjacent hydrogen atoms to form a cyclic structure.

[0353] As a preferred group of compounds having the skeleton (20a), compounds represented by the following general formula (20a) can be exemplified.

[0354] General formula (20a)

[0355] [Chemical formula 36]

[0356]

[0357] In the general formula (20a), Ar 1 ~Ar 4 R each independently represents a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group. 41 and R 42 Each independently represents a substituted or unsubstituted alkyl group. m1 and m2 each independently represent an integer of 0 to 5, n1 and n3 each independently represent an integer of 0 to 4, and n2 and n4 each independently represent an integer of 0 to 3. 1 , A 2 Each independently represents a hydrogen atom, a deuterium atom or a substituent.

[0358] In one aspect of the present invention, n1 to n4 each independently represent an integer of 0 to 2. In a preferred aspect of the present invention, at least one of n1 to n4 is 1 or more, preferably at least one of n1 and n2 is 1 or more, and at least one of n3 and n4 is 1 or more. In one aspect of the present invention, n1 and n3 are each independently 1 or 2, and n2 and n4 are 0. In one aspect of the present invention, n2 and n4 are each independently 1 or 2, and n1 and n3 are 0. In one aspect of the present invention, n1 to n4 are each independently 1 or 2. In one aspect of the present invention, n1 and n3 are equal, and n2 and n4 are equal. In one aspect of the present invention, n1 and n3 are 1, and n2 and n4 are 0. In one aspect of the present invention, n1 and n3 are 0, and n2 and n4 are 1. In one aspect of the present invention, n1 to n4 are all 1. Ar 1 ~Ar 4 The bonding position of Ar may be at least one of the 3rd and 6th positions of the carbazole ring, or at least one of the 2nd and 7th positions, or at least one of the 1st and 8th positions, or at least one of the 4th and 5th positions. 1 ~Ar 4 The bonding position of can be both the 3rd and 6th positions of the carbazole ring, can also be both the 2nd and 7th positions, can also be both the 1st and 8th positions, can also be both the 4th and 5th positions. For example, it can be preferred to select at least one of the 3rd and 6th positions, or it can be further preferred to select both the 3rd and 6th positions. In a preferred aspect of the present invention, Ar 1 ~Ar 4 In a preferred aspect of the present invention, Ar 1 ~Ar 4 Each is independently a substituted or unsubstituted aryl group, more preferably a substituted or unsubstituted phenyl group or naphthyl group, and still more preferably a substituted or unsubstituted phenyl group. The substituent may include a group selected from any one of the substituent groups A to E described below, but is preferably an unsubstituted phenyl group. 1 ~Ar 4 Preferred specific examples may include phenyl, o-biphenyl, m-biphenyl, p-biphenyl, and terphenyl.

[0359] In one aspect of the present invention, m1 and m2 are each independently 0. In one aspect of the present invention, m1 and m2 are each independently any integer from 1 to 5. In one aspect of the present invention, m1 and m2 are equal. In one aspect of the present invention, R 41 and R 42It is an alkyl group having 1 to 6 carbon atoms, for example, it can be selected from alkyl groups having 1 to 3 carbon atoms or a methyl group. Regarding the substitution position of the alkyl group, the carbon atom bonded to the boron atom can be set to the 1st position, and examples include only the 2nd position, only the 3rd position, only the 4th position, the 3rd position and the 5th position, the 2nd position and the 4th position, the 2nd position and the 6th position, the 2nd position, the 4th position and the 6th position, etc., preferably at least the 2nd position, and more preferably at least the 2nd position and the 6th position.

[0360] About A 1 and A 2 For the description and preferred range of , reference can be made to the corresponding description of general formula (20).

[0361] The following are specific examples of the compound represented by the general formula (20a). The compound represented by the general formula (20a) that can be used in the present invention is not to be construed as being limited to the following specific examples.

[0362] [Chemical formula 37-1]

[0363]

[0364] [Chemical formula 37-2]

[0365]

[0366] [Chemical formula 37-3]

[0367]

[0368] [Chemical formula 37-4]

[0369]

[0370] [Chemical formula 37-5]

[0371]

[0372] [Chemical formula 37-6]

[0373]

[0374] [Chemical formula 37-7]

[0375]

[0376] As a preferred group of compounds having the skeleton (20b), compounds represented by the following general formula (20b) can be exemplified.

[0377] General formula (20b)

[0378] [Chemical formula 38]

[0379]

[0380] In the general formula (20b), Ar 5 ~Ar 8 R each independently represents a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group. 43 and R 44 Each independently represents a substituted or unsubstituted alkyl group. m3 and m4 each independently represent an integer of 0 to 5, n6 and n8 each independently represent an integer of 0 to 3, and n5 and n7 each independently represent an integer of 0 to 4. 1 , A 2 Each independently represents a hydrogen atom, a deuterium atom or a substituent. 5 ~Ar 8 , R 43 and R 44 , m3 and m4, n5~n8, A 1 , A 2 For details, please refer to Ar in general formula (20a) 1 ~Ar 4 , R 41 and R 42 、m1 and m2、n1~n4、A 1 , A 2 Records of.

[0381] The following are specific examples of the compound represented by the general formula (20b). The compound represented by the general formula (20b) that can be used in the present invention is not to be construed as being limited to the following specific examples.

[0382] [Chemical formula 39]

[0383]

[0384] In a preferred aspect of the present invention, a compound represented by the following general formula (21) is used as a light-emitting material.

[0385] [Chemical formula 40]

[0386] General formula (21)

[0387]

[0388] In the above general formula (21), Ar 1 ~Ar 3 Each independently represents an aromatic ring or a heteroaromatic ring, at least one hydrogen atom in these rings may be substituted, and the rings may be fused. When the hydrogen atom is substituted, it is preferably substituted by a group selected from the group consisting of a deuterium atom, an aryl group, a heteroaryl group, and an alkyl group, or a group consisting of two or more groups. Furthermore, when the rings are fused, it is preferably fused with a benzene ring or a heteroaromatic ring (e.g., a furan ring, a thiophene ring, a pyrrole ring, etc.). Ra and R a’ 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 They may be bonded to each other to form a ring structure.

[0389] The compound represented by general formula (21) preferably contains at least one carbazole structure. For example, one benzene ring constituting the carbazole structure may be Ar 1 The ring represented by the carbazole structure can be Ar 2 The ring represented by the carbazole structure can be Ar 3 Furthermore, the carbazolyl group may be combined with Ar 1 ~Ar 3 For example, a substituted or unsubstituted carbazole-9-yl group may be bonded to Ar 3 The ring bonding represented.

[0390] Fused aromatic ring structures such as anthracene, pyrene, and perylene can be combined with Ar 1 ~Ar 3 bonding. And, Ar 1 ~Ar 3 The ring represented may be one ring constituting a condensed aromatic ring structure. a and R a’ At least one of the groups may be a group having a condensed aromatic ring structure.

[0391] The skeleton represented by the general formula (21) may exist in a plurality of compounds. For example, the skeletons represented by the general formula (21) may be bonded to each other via a single bond or a linking group. In addition, in the skeleton represented by the general formula (21), a structure showing a multiple resonance effect in which benzene rings are connected to each other via a boron atom, a nitrogen atom, an oxygen atom, or a sulfur atom may be further added.

[0392] In a preferred aspect of the present invention, a compound represented by the following general formula (22) is used as a light-emitting material.

[0393] [Chemical formula 41]

[0394] General formula (22)

[0395]

[0396] In the general formula (22), X 1 and X 2 Each independently represents O or S. 1 and Y 2 Each independently represents a single bond, O, S or C(R a )(R b ). 1 ~R 22 , R a , R b Each independently represents a hydrogen atom, a deuterium atom or a substituent, but R 1 ~R 22 At least one of R is a substituent. 1 and R 2 , R 2 and R 3 , R 3 and R 4 , R 5 and R 6 , R 6 and R 7 , R 7 and Y 1 , Y 1 and R 8 , R 8 and R 9 , R 9 and R 10 , R 10 and R 11 , R 12 and R 13 , R 13 and R 14 , R 14 and R 15 , R 16 and R 17 , R 17 and R 18 , R 18 and Y 2 , Y 2 and R 19 , R 19 and R 20 , R 20 and R 21 , R 21 and R 22 They can bond to each other to form a ring structure. 21 and R 1 , R 4 and R 5 , R 10 and R 12 , R15 and R 16 They are not bonded to each other to form a ring structure. 1 , CR 2 , CR 3 , CR 4 , CR 5 , CR 6 , CR 7 , CR 8 , CR 9 , CR 10 , CR 11 , CR 12 , CR 13 , CR 14 , CR 15 , CR 16 , CR 17 , CR 18 , CR 19 , CR 20 , CR 21 , CR 22 Can be replaced by N.

[0397] In the general formula (22), X 1 and X 2 Each independently represents O or S. In a preferred aspect of the present invention, X 1 and X 2 In one aspect of the present invention, X 1 and X 2 In one aspect of the present invention, X 1 and X 2 One of them is O and the other is S.

[0398] In the general formula (22), Y 1 and Y 2 Each independently represents a single bond, O, S or C(R a )(R b ). In a preferred aspect of the present invention, Y 1 and Y 2 In one aspect of the present invention, Y 1 and Y 2 In one aspect of the present invention, Y 1 and Y 2 In one aspect of the present invention, Y 1 and Y 2 Both are C(R a )(R b ). In one aspect of the present invention, X 1 and X 2One of the is a single bond and the other is O or S. In one aspect of the invention, X 1 and X 2 One of them is 0 and the other is S.

[0399] In a preferred aspect of the present invention, X 1 and X 2 All are O, Y 1 and Y 2 In one preferred aspect of the present invention, X 1 and X 2 Both S, Y 1 and Y 2 are single bonds, O or S, more preferably single bonds. 1 and X 2 All are O, Y 1 and Y 2 All are O, S or C (R a )(R b ), more preferably all are O or S, and further preferably all are O. In one aspect of the present invention, X 1 and X 2 Both S, Y 1 and Y 2 All are O, S or C (R a )(R b ), more preferably all are O or S.

[0400] In the general formula (22), R 1 ~R 22 , R a , R b Each independently represents a hydrogen atom, a deuterium atom or a substituent, but R 1 ~R 22 At least one of them is a substituent. The substituent described herein may be selected from, for example, substituent group A, substituent group B, substituent group C, substituent group D, or substituent group E. In a preferred aspect of the present invention, R 1 ~R 22 is a group consisting of one or more selected from the group consisting of hydrogen atoms, deuterium atoms, alkyl groups and aryl groups (part or all of the hydrogen atoms in the group may be substituted by deuterium atoms) or a substituted or unsubstituted diarylamino group (the two aryl groups constituting the diarylamino group may be connected to each other by a connecting group). In a preferred aspect of the present invention, R a , R bEach independently represents one group or a combination of two or more selected from the group consisting of a hydrogen atom, a deuterium atom, an alkyl group, and an aryl group (a part or all of the hydrogen atoms in the group may be substituted with a deuterium atom).

[0401] In a preferred aspect of the present invention, R 1 ~R 22 The substituent that can be used is a group selected from the group consisting of alkyl and aryl groups or a group composed of two or more groups (a part or all of the hydrogen atoms present in the group can be replaced by deuterium atoms). For example, it is an alkyl group that can be replaced by one or more selected from the group consisting of deuterium atoms and aryl groups. It is preferably an aryl group that can be replaced by one or more selected from the group consisting of deuterium atoms, alkyl groups and aryl groups, and more preferably a phenyl group that can be replaced by one or more selected from the group consisting of deuterium atoms, alkyl groups and aryl groups.

[0402] In one aspect of the present invention, R 1 ~R 22 Substituents that may be employed may be aryl groups substituted with electron withdrawing groups.

[0403] In a preferred aspect of the present invention, R 1 ~R 22 The substituents that can be used are substituted or unsubstituted diarylamino groups. The two aryl groups constituting the diarylamino group described herein can be connected to each other by a linking group. For example, a single bond, -O-, -S-, -C(R c )(R d )-、-N(R e )-make a connection. c , R d , R e Each independently represents a hydrogen atom, a deuterium atom or a substituent, and is preferably a group selected from the group consisting of a hydrogen atom, a deuterium atom, an alkyl group and an aryl group or a group consisting of two or more thereof (a part or all of the hydrogen atoms present in the group may be substituted by a deuterium atom). The diarylamino group may be substituted by a substituent, and the substituent may be selected from, for example, the substituent group A, the substituent group B, the substituent group C, the substituent group D, or the substituent group E. In a preferred aspect of the present invention, the substituent of the diarylamino group is a group selected from the group consisting of a deuterium atom, an alkyl group and an aryl group or a group consisting of two or more thereof (a part or all of the hydrogen atoms present in the group may be substituted by a deuterium atom).

[0404] R 1 ~R 22The substituted or unsubstituted diarylamino group that can be used is preferably a substituted or unsubstituted carbazole-9-yl group. The two benzene rings constituting the carbazole-9-yl group may be further condensed with other rings, respectively and independently.

[0405] R 1 ~R 22 The number of substituents in is preferably 1 to 12, more preferably 1 to 8, and even more preferably 1 to 6, and can be selected from the range of 1 to 3, or from the range of 4 to 6. More preferably, it is 4 to 6. In a preferred aspect of the present invention, R 2 , R 3 , R 6 , R 9 , R 13 , R 14 , R 17 , R 20 1 to 6 of the group consisting of are substituents, and more preferably only selected from R 2 , R 3 , R 6 , R 9 , R 13 , R 14 , R 17 , R 20 1 to 6 of the group consisting of are substituents. In a preferred aspect of the present invention, R 6 , R 9 , R 17 , R 20 For example, only R 6 , R 9 , R 17 , R 20 For example, only R 2 , R 6 , R 9 , R 13 , R 17 , R 20 For example, only R 3 , R 6 , R 9 , R 14 , R 17 , R 20 is a substituent. 1 ~R 22 When there are two or more substituted or unsubstituted aryl groups in the aryl group, the two or more aryl groups are preferably the same, but may be different.

[0406] R 1 ~R 22The total number of carbon atoms of may be, for example, 10 or more, 20 or more, or 30 or more, and may be 80 or less, 60 or less, or 40 or less. In one aspect of the present invention, R 1 ~R 22 The total number of carbon atoms of is selected from the range of 10 to 80, preferably from the range of 10 to 60. In a preferred aspect of the present invention, R 1 ~R 22 The total number of carbon atoms is selected within the range of 20 to 40, for example, within the range of 20 to 30 or within the range of 31 to 40.

[0407] R 1 ~R 22 The total number of benzene rings is selected from the range of 0 to 24. For example, it can be 1 or more, 2 or more, 4 or more, or 6 or more, and can be 18 or less, 12 or less, 8 or less, or 6 or less. In one aspect of the present invention, R 1 ~R 22 The total number of benzene rings is selected from the range of 2 to 8, preferably from the range of 2 to 6, for example, can be selected from the range of 4 to 6.

[0408] In a preferred aspect of the present invention, the compound represented by the general formula (22) is selected from the following compound group.

[0409] [Chemical formula 42-1]

[0410]

[0411] [Chemical formula 42-2]

[0412]

[0413] [Chemical formula 42-3]

[0414]

[0415] In a preferred aspect of the present invention, a compound containing a BODIPY (4,4-difluoro-4-bora-3a,4a-diaza-s-indacene) structure is used as a light-emitting material. For example, a compound represented by the following general formula (23) is used.

[0416] General formula (23)

[0417] [Chemical formula 43]

[0418]

[0419] In the general formula (23), R 1 ~R 7 are independently a hydrogen atom, a deuterium atom or a substituent. 1 ~R 7 At least one of them is preferably a group represented by the following general formula (24).

[0420] General formula (24)

[0421] [Chemical formula 44]

[0422]

[0423] In the general formula (24), R 11 ~R 15 Each independently represents a hydrogen atom, a deuterium atom or a substituent, and * represents a bonding position.

[0424] The group represented by the general formula (24) may be R 1 ~R 7 In one preferred aspect of the present invention, R 1 ~R 7 In a preferred aspect of the present invention, at least R 1 , R 3 , R 5 , R 7 is a group represented by the general formula (24). In a preferred aspect of the present invention, only R 1 , R 3 , R 4 , R 5 , R 7 is a group represented by the general formula (24). In a preferred aspect of the present invention, R 1 , R 3 , R 4 , R 5 , R 7 is a group represented by the general formula (24), 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 All of them are groups represented by the general formula (24).

[0425] In a preferred aspect of the present invention, R1 and R 7 In a preferred aspect of the present invention, R 3 and R 5 In a preferred aspect of the present invention, R 2 and R 6 In a preferred aspect of the present invention, R 1 and R 7 Same, R 3 and R 5 The same, and R 1 and R 3 In a preferred aspect of the present invention, R 1 , R 3 , R 5 , R 7 In a preferred aspect of the present invention, R 1 and R 4 and R 7 Same, R 3 and R 5 In a preferred aspect of the present invention, R 3 and R 4 and R 5 Same, R 1 and R 7 In a preferred aspect of the present invention, R 1 , R 3 , R 5 , R 7 Both with R 4 different.

[0426] As R of the general formula (24) 11 ~R 15 The substituents that can be used include, for example, groups selected from Substituent Group A. 11 ~R 15The substituents that can be used are preferably one group or a combination of two or more selected from the group consisting of substituted or unsubstituted alkyl groups (e.g., having 1 to 40 carbon atoms), substituted or unsubstituted alkoxy groups (e.g., having 1 to 40 carbon atoms), substituted or unsubstituted aryl groups (e.g., having 6 to 30 carbon atoms), substituted or unsubstituted aryloxy groups (e.g., having 6 to 30 carbon atoms), and substituted or unsubstituted amino groups (e.g., having 0 to 20 carbon atoms) (hereinafter, these groups are referred to as "groups of substituent group C"). Among the substituent group C, it is preferred to select an unsubstituted alkyl group having 1 to 20 carbon atoms, an unsubstituted alkoxy group having 1 to 20 carbon atoms, an unsubstituted aryl group having 6 to 14 carbon atoms, an aryloxy group having 6 to 14 carbon atoms, or an unsubstituted diarylamino group having 5 to 20 ring skeleton constituent atoms (hereinafter, these groups are referred to as "groups of substituent group D"). The substituted amino group described herein is preferably a disubstituted amino group, and the two substituents for the amino group are preferably independently substituted or unsubstituted aryl groups, substituted or unsubstituted heteroaryl groups, or substituted or unsubstituted alkyl groups, and are particularly preferably substituted or unsubstituted aryl groups (diarylamino groups). Substituents that can be used for the two aryl groups of the diarylamino group may be selected from groups of substituent group A, groups of substituent group B, or groups of substituent group C. The two aryl groups in the diarylamino group may be bonded to each other via a single bond or a linking group, and for the linking group described herein, reference may be made to R 33 and R 34 Specific examples of the diarylamino group include substituted or unsubstituted carbazole-9-yl groups.

[0427] In a preferred aspect of the present invention, only R 13 is a substituent, R 11 , R 12 , R 14 , R 15 In a preferred aspect of the present invention, only R 11 is a substituent, R 12 , R 13 , R 14 , R 15 In a preferred aspect of the present invention, only R 11 and R 13 is a substituent, R 12 , R 14 , R 15 A hydrogen atom.

[0428] In the general formula (23), R 1 ~R 7 In the formula (24), R11 ~R 15 are all hydrogen atoms (i.e., phenyl). 2 , R 4 , R 6 It may be phenyl.

[0429] In the general formula (23), R 8 and R 9 Preferably, each independently represents one or a combination of two or more 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 It is a halogen atom, and is particularly preferably a fluorine atom.

[0430] In one aspect of the present invention, R present in the general formula (23) 1 ~R 9 The total number of substituted or unsubstituted alkoxy groups, substituted or unsubstituted aryloxy groups, and substituted or unsubstituted amino groups in the formula (23) is preferably three or more, for example, a compound having three or four substituted alkoxy groups may be used. More preferably, R 1 ~R 7 The total number of substituted or unsubstituted alkoxy groups, substituted or unsubstituted aryloxy groups, and substituted or unsubstituted amino groups in the compound is preferably three or more, for example, a compound having three or four substituted alkoxy groups may be used. 8 and R 9 There may be no alkoxy group, aryloxy group or amino group in the general formula (23). 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 in the compound is preferably three or more, for example, a compound having three or four substituted alkoxy groups may be used. 2 , R 6 , R 8 , R 9There may be no alkoxy, aryloxy, or amino in R. In a preferred aspect of the present invention, there are three or more substituted or unsubstituted alkoxy groups. In a preferred aspect of the present invention, there are four or more substituted or unsubstituted alkoxy groups. In a preferred aspect of the present invention, there are one or more substituted or unsubstituted alkoxy groups and two or more substituted or unsubstituted aryloxy groups. In a preferred aspect of the present invention, there are two or more substituted or unsubstituted alkoxy groups and one or more substituted or unsubstituted amino groups. In a preferred aspect of the present invention, in R 1 , R 4 , R 7 In one preferred aspect of the present invention, in R 1 , R 4 , R 7 There may be a substituted or unsubstituted alkoxy group in each of the groups.

[0431] In one aspect of the present invention, R present in the general formula (23) 1 ~R 9 The total number of substituents having a Hammett's σp value of less than -0.2 is three or more. Substituents having a Hammett's σp value of less than -0.2 may include, for example, a methoxy group (-0.27), an ethoxy group (-0.24), a n-propoxy group (-0.25), an isopropoxy group (-0.45), and an n-butoxy group (-0.32). On the other hand, fluorine atoms (0.06), methyl groups (-0.17), ethyl groups (-0.15), tert-butyl groups (-0.20), n-hexyl groups (-0.15), and cyclohexyl groups (-0.15) are not substituents having a Hammett's σp value of less than -0.2.

[0432] In one aspect of the present invention, R present in the general formula (23) can be used 1 ~R 9 The number of substituents having a Hammett's σp value of less than -0.2 is three or four. More preferably, R 1 ~R 7 The number of substituents having a Hammett's σp value of less than -0.2 is preferably three or more, for example, a compound having three substituents or a compound having four substituents can be used. 8 and R 9 There may be no substituent with a Hammett's σp value of less than -0.2. More preferably, R in the general formula (23) 1 , R 3 , R 4 , R 5 , R 7The number of substituents having a Hammett's σp value of less than -0.2 is preferably three or more, for example, a compound having three substituents or a compound having four substituents can be used. 2 , R 6 , R 8 , R 9 There may be no substituents having a Hammett's σp value of less than -0.2. In a preferred aspect of the present invention, in R 1 , R 4 , R 7 There are substituents with Hammett's σp value less than -0.2.

[0433] The following include preferred compounds that can be used as light-emitting materials. In the structural formulas of the following exemplary compounds, t-Bu represents a tert-butyl group.

[0434] [Chemical formula 45-1]

[0435]

[0436] [Chemical formula 45-2]

[0437]

[0438] [Chemical formula 45-3]

[0439]

[0440] [Chemical formula 45-4]

[0441]

[0442] The derivatives of the above exemplary compounds may 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.

[0443] In addition, the compounds described in paragraphs 0220 to 0239 of WO2015 / 022974, paragraphs 0066 and 0117 of WO2019 / 111971, and paragraphs 0196 to 0255 of WO2021 / 015177 can also be particularly preferably used as the light-emitting material of the present invention.

[0444] In addition, in this article, "alkyl" can be any one of straight chain, branched chain, and cyclic. And, two or more of the straight chain part, cyclic part, and branched chain part can be mixed. The number of carbon atoms of the alkyl group can be set to, for example, more than 1, more than 2, or more than 4. And, the number of carbon atoms can be set to less than 30, less than 20, less than 10, less than 6, or less than 4. Specific examples of alkyl groups can include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, n-hexyl, isohexyl, 2-ethylhexyl, n-heptyl, isoheptyl, n-octyl, isooctyl, n-nonyl, isononyl, n-decyl, isodecyl, cyclopentyl, cyclohexyl, and cycloheptyl. The alkyl group of the substituent can be further substituted by an aryl group.

[0445] "Alkenyl" can be any of straight chain, branched chain, and cyclic. Furthermore, two or more of the straight chain part, cyclic part, and branched chain part can be mixed. The number of carbon atoms of the alkenyl group can be set to 2 or more, 4 or more, for example. Furthermore, the number of carbon atoms can be set to 30 or less, 20 or less, 10 or less, 6 or less, or 4 or less. Specific examples of alkenyl groups can include vinyl, n-propenyl, isopropenyl, n-butenyl, isobutenyl, n-pentenyl, isopentenyl, n-hexenyl, isohexenyl, and 2-ethylhexenyl. The alkenyl group of the substituent group can be further substituted by a substituent group.

[0446] "Aryl" and "heteroaryl" may be a single ring or a condensed ring formed by the condensation of two or more rings. In the case of a condensed ring, the number of condensed rings is preferably 2 to 6, for example, it can be selected from 2 to 4. Specific examples of rings may include benzene rings, pyridine rings, pyrimidine rings, triazine rings, naphthalene rings, anthracene rings, phenanthrene rings, triphenylene rings, quinoline rings, pyrazine rings, quinoxaline rings, naphthyridine rings, or rings condensed from these. Specific examples of aryl or heteroaryl may include phenyl, 1-naphthyl, 2-naphthyl, 1-anthryl, 2-anthryl, 9-anthryl, 2-pyridyl, 3-pyridyl, 4-pyridyl. The number of atoms constituting the ring skeleton of the aryl is preferably 6 to 40, more preferably 6 to 20, and may be selected within the range of 6 to 14 or within 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 can be selected within the range of 5 to 14 or 5 to 10. The "arylene group" and "heteroaryl group" can be defined by replacing the valence number in the description of the aryl group and the heteroaryl group from 1 to 2.

[0447] Herein, the "substituent group A" means a substituent selected from a hydroxyl group, a halogen atom (e.g., a fluorine atom, a chlorine atom, a bromine atom, an iodine atom), an alkyl group (e.g., having 1 to 40 carbon atoms), an alkoxy group (e.g., having 1 to 40 carbon atoms), an alkylthio group (e.g., having 1 to 40 carbon atoms), an aryl group (e.g., having 6 to 30 carbon atoms), an aryloxy group (e.g., having 6 to 30 carbon atoms), an arylthio group (e.g., having 6 to 30 carbon atoms), a heteroaryl group (e.g., having 5 to 30 atoms constituting the ring skeleton), a heteroaryloxy group (e.g., having The present invention also includes one group or a combination of two or more groups selected from the group consisting of a thioalkyl group (e.g., a ring skeleton having 5 to 30 atoms), an acyl group (e.g., a ring skeleton having 1 to 40 carbon atoms), an alkenyl group (e.g., a ring skeleton having 1 to 40 carbon atoms), an alkynyl group (e.g., a ring skeleton having 1 to 40 carbon atoms), an alkoxycarbonyl group (e.g., a ring skeleton having 1 to 40 carbon atoms), an aryloxycarbonyl group (e.g., a ring skeleton having 1 to 40 carbon atoms), a heteroaryloxycarbonyl group (e.g., a ring skeleton having 1 to 40 carbon atoms), and a nitro group.

[0448] Herein, "substituent group B" means one group or a combination of two or more groups selected from the group consisting of alkyl (e.g., having 1 to 40 carbon atoms), alkoxy (e.g., having 1 to 40 carbon atoms), aryl (e.g., having 6 to 30 carbon atoms), aryloxy (e.g., having 6 to 30 carbon atoms), heteroaryl (e.g., having 5 to 30 ring skeleton atoms), heteroaryloxy (e.g., having 5 to 30 ring skeleton atoms), and diarylamino (e.g., having 0 to 20 carbon atoms).

[0449] Herein, "substituent group C" means 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), heteroaryl groups (e.g., having 5 to 20 ring skeleton atoms), and diarylamino groups (e.g., having 12 to 20 carbon atoms).

[0450] Herein, "substituent group D" means 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 atoms constituting the ring skeleton).

[0451] Herein, the "substituent group E" means one group or a combination of two or more groups selected from the group consisting of alkyl groups (for example, having 1 to 20 carbon atoms) and aryl groups (for example, having 6 to 22 carbon atoms).

[0452] Herein, when a substituent is described as a “substituent” or “substituted or unsubstituted”, for example, the substituent may be selected from substituent group A, substituent group B, substituent group C, substituent group D, or substituent group E.

[0453] (Other ingredients and constituent elements)

[0454] The composition included in the organic light-emitting element of the present invention may be composed only of the first host material, the second host material, the delayed fluorescence material and the luminescent material, or may include other components. When other components are included, their concentration is preferably 5% by weight or less, more preferably 1% by weight or less, for example, it can be set to 0.01% by weight or less. The composition included in the organic light-emitting element of the present invention is preferably set to the following structure: except for the first host material, the second host material, the delayed fluorescence material and the luminescent material, it does not include a compound for giving and receiving charge or energy, or a metal element other than boron.

[0455] The composition contained in the organic light-emitting element of the present invention can also be composed only of a compound, which is composed of atoms selected from the group consisting of carbon atoms, hydrogen atoms, deuterium atoms, nitrogen atoms, boron atoms, oxygen atoms and sulfur atoms. For example, it can be composed only of a compound, which is composed of atoms selected from the group consisting of carbon atoms, hydrogen atoms, deuterium atoms, nitrogen atoms, boron atoms and oxygen atoms. For example, it can be composed only of a compound, which is composed of atoms selected from the group consisting of carbon atoms, hydrogen atoms, deuterium atoms, nitrogen atoms, boron atoms and sulfur atoms. For example, it can be composed only of a compound, which is composed of atoms selected from the group consisting of carbon atoms, hydrogen atoms, deuterium atoms, nitrogen atoms and boron atoms. For example, it can be composed only of a compound, which is composed of atoms selected from the group consisting of carbon atoms, hydrogen atoms, deuterium atoms, nitrogen atoms, oxygen atoms and sulfur atoms. For example, it can be composed only of a compound, which is composed of atoms selected from the group consisting of carbon atoms, hydrogen atoms, deuterium atoms, nitrogen atoms, oxygen atoms and sulfur atoms. For example, it can be composed only of a compound, which is composed of atoms selected from the group consisting of carbon atoms, hydrogen atoms, deuterium atoms and nitrogen atoms. The composition may include a first host material, a second host material, a delayed fluorescent material and a luminescent material, wherein the first host material is composed of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms and oxygen atoms, the second host material is composed of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms and oxygen atoms, the delayed fluorescent material is composed of atoms selected from the group consisting of carbon atoms, hydrogen atoms, deuterium atoms, nitrogen atoms, oxygen atoms and sulfur atoms, and the luminescent material is composed of atoms selected from the group consisting of carbon atoms, hydrogen atoms, deuterium atoms, nitrogen atoms, boron atoms, oxygen atoms and sulfur atoms. Furthermore, the composition may include a first host material, a second host material, a delayed fluorescent material and a luminescent material, wherein the first host material is composed of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms and oxygen atoms, the second host material is composed of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms and oxygen atoms, the delayed fluorescent material is composed of atoms selected from the group consisting of carbon atoms, hydrogen atoms, deuterium atoms and nitrogen atoms, and the luminescent material is composed of atoms selected from the group consisting of carbon atoms, hydrogen atoms, deuterium atoms, nitrogen atoms and boron atoms.

[0456] (Organic electroluminescent element)

[0457] Examples of the organic light-emitting element of the present invention may include an organic electroluminescent element. The organic electroluminescent element has an anode, a cathode, and at least one organic layer including a light-emitting layer between the anode and the cathode. The organic layer may be composed of only the light-emitting layer, or may include an organic layer other than the light-emitting layer. For example, an organic layer may or may not exist between the anode and the light-emitting layer and between the light-emitting layer and the cathode. In other words, the anode and the light-emitting layer may be stacked in direct contact or indirect contact. Furthermore, the light-emitting layer and the cathode may be stacked in direct contact or indirect contact. The light-emitting layer is located between the anode and the cathode, and the light-emitting layer as a whole is preferably arranged in a non-protruding state in the region between the anode and the cathode.

[0458] The organic electroluminescent element may have a substrate supporting an anode, a cathode and at least one organic layer including a light-emitting layer. In this case, the substrate may be arranged on the side of the anode opposite to the light-emitting layer, or on the side of the cathode opposite to the light-emitting layer. Furthermore, the organic electroluminescent element of the present invention may be a top-emitting element in which most of the light is emitted from the side opposite to the substrate, or may be a bottom-emitting element in which most of the light is emitted from the substrate side. Here, "most of the light" means light that accounts for more than 60% of the amount of light emitted from the element.

[0459] A composition comprising a first host material, a second host material, a delayed fluorescent material, and a luminescent material can constitute a luminescent layer. The luminescent layer can be formed by co-evaporating the first host material, the second host material, the delayed fluorescent material, and the luminescent material, or by using a solution obtained by dissolving the first host material, the second host material, the delayed fluorescent material, and the luminescent material and forming it by a coating method. When forming the luminescent layer by co-evaporation, two or more of the first host material, the second host material, the delayed fluorescent material, and the luminescent material can be pre-mixed and added to a crucible or the like as an evaporation source, and the evaporation source is used for co-evaporation to form the luminescent layer. For example, the first host material, the second host material, and the delayed fluorescent material can be pre-mixed to make an evaporation source, and the evaporation source and the luminescent material are co-evaporated to form the luminescent layer.

[0460] Hereinafter, each layer other than each member and the light-emitting layer of the organic electroluminescent element will be described.

[0461] Substrate:

[0462] In some embodiments, the organic electroluminescent element of the present invention is supported by a substrate, wherein the substrate is not particularly limited and may be any of those substrates that have been commonly used in organic electroluminescent elements, such as those formed of glass, transparent plastic, quartz, and silicon.

[0463] anode:

[0464] 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 large work function (above 4 eV). In some embodiments, the metal is Au. In some embodiments, the conductive transparent material is selected from CuI, indium tin oxide (ITO), SnO 2 In some embodiments, an amorphous material such as IDIXO (In 2 O 3 -ZnO) and the like. In some embodiments, the anode is a thin film. In some embodiments, the thin film is made by evaporation or sputtering. In some embodiments, the film is patterned by photolithography. In some embodiments, when the pattern may not require high precision (e.g., about 100 μm or more), the pattern can be formed by evaporation or sputtering of the electrode material with a mask of the desired shape. In some embodiments, when a coating material (such as an organic conductive compound) can be coated, a wet film formation method such as a printing method and a coating method is used. In some embodiments, when the emitted light passes through the anode, the transmittance of the anode is greater than 10%, and the sheet resistance of the anode is less than hundreds of ohms per square. 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.

[0465] cathode:

[0466] In some embodiments, the cathode is made of a metal (less than 4 eV) (called an electron injection metal) having a small work function, an alloy, a conductive compound or a combination thereof. In some embodiments, the electrode material is selected from sodium, sodium-potassium alloy, magnesium, lithium, magnesium-copper mixture, magnesium-silver mixture, magnesium-aluminum mixture, magnesium-indium mixture, aluminum-aluminum oxide (Al 2 O 3 ) mixture, indium, lithium-aluminum mixture and rare earth metal. In some embodiments, a mixture of an electron injecting metal and a second metal is used, and the second metal is a stable metal with a larger work function than the electron injecting metal. In some embodiments, the mixture is selected from magnesium-silver mixture, magnesium-aluminum mixture, magnesium-indium mixture, aluminum-aluminum oxide (Al 2 O 3) mixture, lithium-aluminum mixture and aluminum. In some embodiments, the mixture increases electron injection characteristics and durability against oxidation. In some embodiments, the cathode is manufactured by forming the electrode material into a thin film by evaporation or sputtering. In some embodiments, the sheet resistance of the cathode is less than hundreds of ohms per square. In some embodiments, the thickness of the cathode is in the range of 10nm to 5μm. In some embodiments, the thickness of the cathode is in the range of 50 to 200nm. In some embodiments, in order to transmit the radiated light, any one of the anode and cathode of the organic electroluminescent element is transparent or translucent. In some embodiments, the transparent or translucent electroluminescent element enhances the luminous brightness.

[0467] In some embodiments, the cathode is formed with a conductive transparent material as described for the anode to form a transparent or translucent cathode. In some embodiments, the element comprises an anode and a cathode that are both transparent or translucent.

[0468] Injection layer:

[0469] 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 luminous brightness. In some embodiments, the injection layer includes a hole injection layer and an electron injection layer. The injection layer can be configured 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, there is an injection layer. In some embodiments, there is no injection layer.

[0470] Preferred examples of compounds that can be used as hole injection materials are included below.

[0471] [Chemical formula 46]

[0472]

[0473] Next, preferred examples of compounds that can be used as electron injecting materials are included.

[0474] [Chemical formula 47]

[0475]

[0476] Barrier layer:

[0477] The blocking layer is a layer that can inhibit the charges (electrons or holes) and / or excitons in the light-emitting layer from diffusing to the outside of the light-emitting layer. In some embodiments, the electron blocking layer is between the light-emitting layer and the hole transport layer, and inhibits electrons from passing through the light-emitting layer toward the hole transport layer. In some embodiments, the hole blocking layer is between the light-emitting layer and the electron transport layer, and inhibits holes from passing through the light-emitting layer toward the electron transport layer. In some embodiments, the blocking layer inhibits excitons from diffusing to the outside of the light-emitting layer. In some embodiments, the electron blocking layer and the hole blocking layer constitute an exciton blocking layer. The term "electron blocking layer" or "exciton blocking layer" used herein includes a layer having the functions of both an electron blocking layer and an exciton blocking layer.

[0478] Hole blocking layer:

[0479] The hole blocking layer functions as an electron transport layer. In some embodiments, the hole blocking layer inhibits holes from reaching the electron transport layer while transporting electrons. In some embodiments, the hole blocking layer enhances the probability of re-bonding of electrons and holes in the light-emitting layer. The material used for the hole blocking layer can be the same material as described for the electron transport layer.

[0480] The following are examples of preferred compounds that can be used in the hole blocking layer.

[0481] [Chemical formula 48]

[0482]

[0483] Electron blocking layer:

[0484] The holes are transported by the electron blocking layer. In some embodiments, the electron blocking layer inhibits the electrons from reaching the hole transport layer while transporting the holes. In some embodiments, the electron blocking layer enhances the probability of re-bonding of electrons and holes in the light-emitting layer. The material used for the electron blocking layer can be the same material as described for the hole transport layer.

[0485] Specific examples of preferred compounds that can be used as electron blocking materials are included below.

[0486] [Chemical formula 49-1]

[0487]

[0488] [Chemical formula 49-2]

[0489]

[0490] Exciton blocking layer:

[0491] The exciton blocking layer inhibits the diffusion of excitons generated by the rebonding of holes and electrons in the light-emitting layer to the electron transport layer. In some embodiments, the exciton blocking layer enables the excitons to be effectively confined in the light-emitting layer. In some embodiments, the luminous efficiency of the device is enhanced. In some embodiments, the exciton blocking layer is adjacent to the light-emitting layer on either the anode side and the cathode side and on both sides. In some embodiments, when the exciton blocking layer is on the anode side, the layer may be between the hole transport layer and the light-emitting layer and adjacent to the light-emitting layer. In some embodiments, when the exciton blocking layer is on the cathode side, the layer may be between the light-emitting layer and the cathode and adjacent to the light-emitting layer. In some embodiments, the hole injection layer, the electron blocking layer, or the same layer is between the anode and the exciton blocking layer, and the exciton blocking layer is adjacent to the light-emitting layer on the anode side. In some embodiments, the hole injection layer, the electron blocking layer, the hole blocking layer, or the same layer is between the cathode and the exciton blocking layer, and the exciton blocking layer is adjacent to the light-emitting 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 the excited triplet energy of the light-emitting material, respectively.

[0492] Hole transport layer:

[0493] 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.

[0494] In some embodiments, the hole transport material has one of the injection or transport characteristics of holes and the blocking characteristics of electrons. 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, indole and carbazole derivatives, polyaryl alkane derivatives, pyrazoline derivatives, dihydropyrazolone derivatives, phenylenediamine derivatives, aromatic amine derivatives, amino-substituted chalcone derivatives, oxazole derivatives, styryl anthracene derivatives, fluorenone derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives, aniline copolymers and conductive polymer oligomers (especially thiophene oligomers) or combinations thereof. In some embodiments, the hole transport material is selected from porphyrin compounds, aromatic tertiary amines and styrylamine compounds. In some embodiments, the hole transport material is an aromatic tertiary amine compound. The following includes specific examples of preferred compounds that can be used as hole transport materials.

[0495] [Chemical formula 50]

[0496]

[0497] Electron transport layer:

[0498] 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.

[0499] In some embodiments, the electron transport material only needs to have the function of transporting electrons, which are injected from the cathode into 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, fluorene derivatives, dibenzoquinone derivatives, thiopyran dioxide derivatives, carbodiimides, fluorenyl methane derivatives, anthraquinone dimethane, anthrone derivatives, oxadiazole derivatives, azole derivatives, oxazine derivatives, or combinations thereof or polymers thereof substituted by nitro groups. 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. The following includes specific examples of preferred compounds that can be used as electron transport materials.

[0500] [Chemical formula 51]

[0501]

[0502] In addition, examples of compounds that are preferable as materials that can be added to each organic layer are included. For example, it is conceivable that the compound can be added as a stabilizing material.

[0503] [Chemical formula 52]

[0504]

[0505] Preferred materials that can be used for organic electroluminescent elements are specifically exemplified, but the materials that can be used in the present invention are not limited to the following exemplary compounds. In addition, even compounds exemplified as materials having specific functions can be used as materials having other functions.

[0506] Device:

[0507] In some embodiments, the light emitting layer is incorporated into a device. Examples of devices include, but are not limited to, OLED bulbs, OLED lamps, television screens, computer monitors, mobile phones, and tablet computers.

[0508] In some embodiments, an electronic device includes an OLED having an anode, a cathode, and at least one organic layer including a light-emitting layer between the anode and the cathode.

[0509] In some embodiments, the compositions described herein can be incorporated into various light-sensitive or light-activated devices, such as OLEDs or photovoltaic devices. In some embodiments, the compositions can be suitable for promoting charge transfer or energy transfer within the device and / or for use as hole transport materials. The 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 photodetectors, organic photoreceptors, organic field-quench devices (organic field-quench devices; O-FQDs), light-emitting electrochemical cells (LECs), or organic laser diodes (O-lasers).

[0510] Bulb or Lamp:

[0511] In some embodiments, an electronic device includes an OLED including an anode, a cathode, and at least one organic layer including a light-emitting layer between the anode and the cathode.

[0512] 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 combination of three colors (e.g., RGB). In some embodiments, the combination of OLEDs is a combination of colors other than red, green, or blue (e.g., orange and yellow-green). In some embodiments, the combination of OLEDs is a combination of two, four, or more colors.

[0513] In some embodiments, the device is an OLED lamp having:

[0514] A circuit substrate having a first surface having a mounting surface and a second surface opposite thereto and defining at least one opening;

[0515] At least one OLED is disposed on the mounting surface and has a structure in which the at least one OLED includes an anode, a cathode, and at least one organic layer including a light-emitting layer between the anode and the cathode and emits light;

[0516] A housing for a circuit substrate; and

[0517] At least one connector is disposed at an end of the housing, and the housing and the connector define a package suitable for mounting on a lighting device.

[0518] In some embodiments, the OLED lamp includes a plurality of OLEDs mounted on a circuit substrate so that light is emitted in a plurality of directions. In some embodiments, a portion of the light emitted in a first direction is deflected to be emitted in a second direction. In some embodiments, a reflector is used to deflect the light emitted in the first direction.

[0519] Monitor or Screen:

[0520] In some embodiments, the light-emitting layer of the present invention can be used in a screen or display. In some embodiments, the compounds involved in the present invention are deposited onto a substrate using methods including (but not limited to) vacuum evaporation, deposition, vapor deposition or chemical vapor deposition (CVD). In some embodiments, the substrate is a photoplate structure suitable for double-sided etching, providing unique aspect ratio pixels. The screen (which may also be referred to as a mask) is used in a method for manufacturing an OLED display. The corresponding artwork pattern design promotes extremely steep and narrow tie-bars between pixels in the vertical direction, and promotes larger sweeping angle openings in the horizontal direction. This allows for tight patterning of pixels required for high-definition displays while optimizing chemical vapor deposition onto the TFT substrate.

[0521] The internal patterning of the pixel allows the construction of 3-dimensional pixel openings with varying aspect ratios in the horizontal and vertical directions. In addition, etching in specific areas is suppressed using imaged "strips" or halftone circles within the pixel area until these specific patterns are undercut and leave the substrate. At this point, all pixel areas are processed at the same etching rate, but the depth varies depending on the halftone pattern. Changing the size and spacing of the halftone pattern allows etching to be suppressed at different rates within the pixel, allowing for localized deeper etching required to form steep vertical bevels.

[0522] The preferred material for the evaporation mask is invar. Invar is a metal alloy that is cold rolled into long thin sheets in a steel mill. Invar cannot be electrodeposited onto a spin mandrel as a nickel mask. An appropriate and low-cost method for forming the opening area in the evaporation mask is a method based on wet chemical etching.

[0523] In some embodiments, the screen or display pattern is a matrix of pixels on a substrate. In some embodiments, the screen or display pattern is made using lithography (e.g., photolithography and e-beam lithography). In some embodiments, the screen or display pattern is made using wet chemical etching. In other embodiments, the screen or display pattern is made using plasma etching.

[0524] Device manufacturing method:

[0525] OLED displays are generally manufactured by forming a large motherboard and then cutting the motherboard into unit board units. Generally speaking, each unit board on the motherboard is formed by forming a thin film transistor (TFT) including an active layer and a source / drain electrode on a base substrate, applying a planarization film to the TFT, and sequentially forming a pixel electrode, a light emitting layer, a counter electrode and an encapsulation layer, and cutting from the motherboard.

[0526] In another aspect of the present invention, there is provided a method for manufacturing an organic light emitting diode (OLED) display, the method comprising:

[0527] The process of forming a barrier layer on the base substrate of the mother board;

[0528] A process of forming a plurality of display units from a unit panel unit on the barrier layer;

[0529] forming an encapsulation layer on each of the display units of the unit panel; and

[0530] A process of coating an organic film on the interface portion between the unit plates.

[0531] In some embodiments, the barrier layer is an inorganic film formed of, for example, SiNx, and an edge portion of the barrier layer is covered with an organic film formed of polyimide or acryl. In some embodiments, the organic film helps to gently cut the mother board into unit board units.

[0532] In some embodiments, the thin film transistor (TFT) layer has a light emitting layer, a gate electrode, and a source electrode / drain electrode. Each of the plurality of display units may include a thin film transistor (TFT), a planarization film formed on the TFT layer, and a light emitting unit formed on the planarization film, wherein the organic film applied to the interface portion is formed of the same material as the material of the planarization film and is formed at the same time as the planarization film is formed. In some embodiments, the light emitting unit is connected to the TFT layer with a passivation layer, a planarization film, and an encapsulation layer therebetween, and the encapsulation layer covers and protects the light emitting unit. In some embodiments of the manufacturing method, the organic film contacts neither the display unit nor the encapsulation layer.

[0533] Each of the organic film and the planarization film may include any one of polyimide and acryl. 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, before forming a barrier layer on one surface of the base substrate formed of polyimide, mounting a carrier substrate formed of a glass material on another surface of the base substrate, and before cutting along the interface portion, separating the carrier substrate from the base substrate. In some embodiments, the OLED display is a flexible display.

[0534] In some embodiments, the passivation layer is an organic film disposed on the TFT layer to cover the TFT layer. In some embodiments, the planarization film is an organic film formed on the passivation layer. In some embodiments, the planarization film is formed of polyimide or acryl, as is the organic film formed on the edge portion of the barrier layer. In some embodiments, when manufacturing an OLED display, the planarization film and the organic film are formed simultaneously. In some embodiments, the organic film may be formed on the edge portion of the barrier layer so that a portion of the organic film directly contacts the base substrate, and the remaining portion of the organic film contacts the barrier layer while surrounding the edge portion of the barrier layer.

[0535] In some embodiments, the light emitting layer comprises a pixel electrode, an opposite electrode, and an organic light emitting layer disposed between the pixel electrode and the opposite electrode. In some embodiments, the pixel electrode is connected to a source electrode / drain electrode of a TFT layer.

[0536] In some embodiments, when a voltage is applied to the pixel electrode via the TFT layer, an appropriate voltage is formed between the pixel electrode and the opposite electrode, whereby the organic light-emitting layer emits light, thereby forming an image. Hereinafter, an image forming unit having a TFT layer and a light-emitting unit is referred to as a display unit.

[0537] In some embodiments, the encapsulation layer that covers the display unit and prevents external moisture from penetrating can be formed to have a thin film encapsulation structure in which an organic film and an inorganic film are alternately stacked. In some embodiments, the encapsulation layer has a thin film encapsulation structure in which a plurality of thin films are stacked. In some embodiments, the organic film applied to the interface portion is spaced apart from each of the plurality of display units. In some embodiments, the organic film is formed so that a portion of the organic film directly contacts the base substrate, and the remaining portion of the organic film contacts the barrier layer while surrounding the edge portion of the barrier layer.

[0538] In one embodiment, the OLED display is flexible and uses a soft base substrate formed of polyimide. In some embodiments, the base substrate is formed on a carrier substrate formed of a glass material, and then the carrier substrate is separated.

[0539] In some embodiments, a barrier layer is formed on a surface of the base substrate on a side opposite to the carrier substrate. In one embodiment, the barrier layer is patterned according to the size of each unit board. For example, while the base substrate is formed over the entire surface of the mother board, the barrier layer is formed according to the size of each unit board, thereby forming a groove at the interface portion between the unit board barrier layers. Each unit board can be cut along the groove.

[0540] In some embodiments, the manufacturing method further comprises a process of cutting along the interface portion, wherein a groove is formed in the barrier layer, wherein at least a portion of the organic film is formed in the groove, and the groove does not penetrate into the base substrate. In some embodiments, the TFT layer of each unit board is formed, and a passivation layer (i.e., an inorganic film) and a planarization film (i.e., an organic film) are arranged on the TFT layer to cover the TFT layer. While forming a planarization film formed by, for example, polyimide or acryl, the groove at the interface portion is covered with an organic film formed by, for example, polyimide or acryl. This is when cracking is prevented from occurring by allowing the organic film to absorb impact, which is generated when each unit board is cut along the groove at the interface portion. That is, if the entire barrier layer is completely exposed without an organic film, the impact generated when each unit board is cut along the groove at the interface portion is transferred to the barrier layer, thereby increasing the risk of cracking. However, in one embodiment, because the groove at the interface portion between the barrier layers is covered with an organic film, and the organic film absorbs the impact that would otherwise be transferred to the barrier layer, each unit board can be cut gently, and cracks can be prevented from occurring in the barrier layer. In one embodiment, the organic film covering the groove at the interface portion and the planarization film are spaced apart from each other. For example, if the organic film and the planarization film are connected to each other as a single layer, then because external moisture may penetrate into the display unit via the planarization film and a portion where the organic film remains, the organic film and the planarization film are spaced apart from each other so that the organic film is spaced apart from the display unit.

[0541] In some embodiments, the display unit is formed by forming a light-emitting unit, and an encapsulation layer is disposed on the display unit to cover the display unit. Thus, after the motherboard is completely manufactured, the carrier substrate supporting the base substrate is separated from the base substrate. In some embodiments, when a laser beam is irradiated toward the carrier substrate, the carrier substrate is separated from the base substrate due to the difference in thermal expansion coefficient between the carrier substrate and the base substrate.

[0542] In some embodiments, the mother board is cut into unit board units. In some embodiments, the mother board is cut along the interface portion between the unit boards by using a cutting machine. In some embodiments, because the groove at the interface portion along which the mother board is cut is covered with an organic film, the organic film absorbs impact during cutting. In some embodiments, cracks can be prevented from occurring in the barrier layer during cutting.

[0543] In some embodiments, the method reduces the defect rate of the product and stabilizes its quality.

[0544] Another aspect is an OLED display having: a barrier layer formed on a base substrate; a display unit formed on the barrier layer; an encapsulation layer formed on the display unit; and an organic film coated on an edge portion of the barrier layer.

[0545] <Design method of organic light-emitting element>

[0546] Next, a method for designing an organic light-emitting element of the present invention will be described.

[0547] The organic light-emitting element designed by the design method of the present invention is an organic light-emitting element having a composition, wherein the composition comprises a first host material, a second host material having a higher HOMO energy level than the first host material, a delayed fluorescence material, and a luminescent material. The organic light-emitting element designed by the design method of the present invention can be an organic electroluminescent element or an organic photoluminescent element. Moreover, in the present invention, such an organic light-emitting element is designed in such a way that the energy level of the HOMO of the second host material and the energy level of the HOMO of the delayed fluorescence material satisfy the relationship of the above formula (a). For the description and preferred range of compounds that can be used as the first host material, the second host material, the delayed fluorescence material, and the luminescent material, specific examples, and the structure of other organic light-emitting elements, reference can be made to the above corresponding description.

[0548] The design method of the organic light-emitting element of the present invention can be performed using a database of host materials storing the physical property values ​​of compounds that can be used as host materials and a database of delayed fluorescence materials storing the physical property values ​​of compounds that can be used as delayed fluorescence materials. In addition, a database of luminescent materials storing the physical property values ​​of compounds that can be used as luminescent materials can also be used. The physical property values ​​stored in these databases are at least the HOMO energy level of each compound, and the LUMO energy level or the lowest excited singlet energy of each compound, the ΔE of the delayed fluorescence material, and the LUMO energy level of each compound can also be stored. ST And other physical property values.

[0549] In one aspect of the present invention, a database storing the HOMO energy level of the host material and the HOMO energy level of the delayed fluorescent material is used to select a combination of a second host material and a delayed fluorescent material that satisfies formula (a). At this time, a first host material having a lower HOMO energy level than the second host material can also be selected at the same time.

[0550] In another aspect of the present invention, as each database of the first host material, the second host material and the delayed fluorescent material, a database storing the energy level of HOMO and the lowest excited singlet energy of each compound is used. The design method of this aspect includes, for example, the following steps: arbitrarily selecting a luminescent material; searching and selecting a delayed fluorescent material with a higher lowest excited singlet energy than the selected specific luminescent material from the database of delayed fluorescent materials; searching for a second host material with a higher lowest excited singlet energy than the selected delayed fluorescent material and a HOMO energy level satisfying the relationship of formula (a) from the database of host materials; and selecting the second host material and the first host material with a lower HOMO energy level than the second host material from the host materials hit in the search, thereby deriving a combination consisting of a specific luminescent material, a specific delayed fluorescent material, a specific second host material and a specific first host material. In addition, the steps of searching and selecting these materials can be interchangeable or performed simultaneously. For example, the search and selection can be performed in the order of the first host material, the second host material, the delayed fluorescent material, and the luminescent material, or they can be searched and selected simultaneously.

[0551] In the design method of the organic light-emitting element of the present invention, it is preferred to select each material in consideration of a case where the carrier balance becomes higher, a case where the driving voltage becomes lower, or a case where the element life (LT95%, etc.) becomes longer. This selection can be performed using the following steps: measuring the carrier balance, driving voltage, or element life (for example, LT95%) of the light-emitting element after various changes are made to the combination of the host material and the delayed fluorescent material; deriving the characteristic quantities of the host material and the delayed fluorescent material that show a correlation with these characteristic values; finding the characteristic quantity that makes the characteristic value become a better value based on the correlation; and selecting the host material and the delayed fluorescent material in a manner having the found characteristic quantity. In addition, the derivation of such characteristic quantities or the selection of a specific host material based on the characteristic quantities can be performed using a deep learning function.

[0552] <Procedure>

[0553] The program of the present invention is a program for implementing the method for designing an organic light-emitting element of the present invention.

[0554] Regarding the steps constituting the program, reference can be made to the description in the above-mentioned section "Method for designing an organic light-emitting element".

[0555] Example

[0556] The following includes embodiments to further specifically illustrate the features of the present invention. The materials, processing contents, processing steps, etc. shown below can be appropriately changed as long as they do not depart from the main purpose of the present invention. Therefore, the scope of the present invention should not be interpreted restrictively by the specific examples shown below. In addition, about the evaluation of luminous performance, source meter (TEKTRONIX, INC. system: 2400 series), semiconductor parameter analyzer (Agilent Technologies Japan, Ltd. system: E5273A), optical power meter measuring device (Newport Corporation system: 1930C), spectrometer (Ocean Optics company system: USB2000), spectroradiometer (TOPCON CORPORATION system: SR-3) and streak camera (Hamamatsu Photonics KK system C4334 type) are used for carrying out.

[0557] <Materials for the Light Emitting Layer Used in Examples and Comparative Examples>

[0558] The host material, delayed fluorescent material and luminescent material used in the following examples and comparative examples are shown below. In the following structural formula, D represents a deuterium atom, and t-Bu represents a tert-butyl group.

[0559] [Chemical formula 53-1]

[0560] Main material

[0561]

[0562] [Chemical formula 53-2]

[0563] Delayed fluorescence material

[0564]

[0565] [Chemical formula 53-3]

[0566] Luminescent Materials

[0567]

[0568] The measured values ​​of HOMO and LUMO of each host material are shown in the following table.

[0569] [Table 1]

[0570]

[0571] (Experimental Example 1) Preparation and Evaluation of Organic Light Emitting Elements

[0572] By vacuum evaporation method, the vacuum degree is 1×10 -6 Pa, HH1, HH2, TT1, and FF1 were respectively deposited from different deposition sources on a quartz substrate to form a mixed film with a thickness of 40 nm, thereby manufacturing element 1. At this time, regarding the concentration in the mixed film, HH1 as the first host material was set to 20 wt %, HH2 as the second host material was set to 40 wt %, TT1 as the delayed fluorescent material was set to 39.9 wt %, and FF1 as the light-emitting material was set to 0.5 wt %.

[0573] The types and concentrations of the first host material, the second host material, the delayed fluorescent material, and the luminescent material were changed as shown in Table 2, and elements 2 to 9 and comparative elements 1 to 2 were prepared in the same manner as element 1. The photoluminescence quantum yield (PLQY) of each prepared PL element based on 300nm excitation light was measured and the results are shown in Table 2. It was confirmed that the PLQY of elements 1 to 9 satisfying formula (a) was higher than that of the comparative element, and had preferred characteristics as an organic light-emitting element. In addition, in Table 2, ΔHOMO is E HOMO (H 2 )-E HOMO (T).

[0574] In addition, in elements 1 to 9 and comparative elements 1 to 2, only the second host material was not used, and elements of a composition composed of three components (three-component elements) were prepared, and the photoluminescence quantum yield was measured in the same manner. The degree of change in the photoluminescence quantum yield of each four-component element of elements 1 to 9 and comparative elements 1 to 2 was confirmed with respect to the photoluminescence quantum yield of the corresponding three-component element. As a result, by changing the three-component element to a four-component element, a decrease of more than 13% in PLQY was observed in all comparative elements 1 to 2, but such a significant decrease in PLQY was not observed in elements 1 to 9.

[0575]

[0576] (Example 2) Preparation of organic electroluminescent element

[0577] A 2 mm thick glass substrate on which an anode composed of 50 nm thick indium tin oxide (ITO) was formed by vacuum deposition was deposited at a vacuum degree of 1×10 -6Pa stacked various thin films. First, HATCN was evaporated to a thickness of 5nm on ITO to form a hole injection layer, and NPD was evaporated to a thickness of 60nm on it to form a hole transport layer. Then, EB1 was evaporated to a thickness of 10nm to form an electron blocking layer. Then, HH1, HH6, TT3 and FF1 were co-evaporated from different evaporation sources to form a 40nm thick light-emitting layer. At this time, regarding the concentration in the light-emitting layer, HH1 as the first main material was set to 39.5% by weight, HH2 as the second main material was set to 20.0% by weight, TT1 as the delayed fluorescent material was set to 40.0% by weight, and FF1 as the light-emitting material was set to 0.5% by weight. Then, HB1 was evaporated to a thickness of 10n m to form a hole blocking layer, and then ET1 was evaporated to a thickness of 30nm to form an electron transport layer. In addition, Liq was evaporated to a thickness of 2nm to form an electron injection layer, and then aluminum (Al) was evaporated to a thickness of 100nm to form a cathode. In this way, an EL element 1 as an organic electroluminescent element (EL element) was produced.

[0578] A comparative EL element 1 was produced by the same steps as the EL element 1 without using HH6 as the second host material.

[0579] Comparative EL element 2 was produced by the same procedure as EL element 1 except that HH8 was used as the second host material instead of HH6.

[0580] When the electrodes of each EL element were energized, it was confirmed that the largest component of light emission from any element was the fluorescence from FF1, which was the light-emitting material (peak light emission wavelength 616 nm). When the time (LT95) for the light emission intensity of each EL element to reach 95% of that at the beginning of the test was measured, the EL element 1 and the comparative EL element 2, whose light-emitting layers were composed of four components, were both 2.5 times or more higher than the comparative EL element 1, whose light-emitting layer was composed of three components. Thus, it was confirmed that the life of the element can be greatly extended by adopting the second host material. Next, the EL element 1 and the comparative EL element 2, whose light-emitting layers were composed of four components, were subjected to a 15.4 mA / cm 2 When the external quantum yield (EQE) was measured, the EL element 1 showed a value as high as 14.1% relative to 9.7% for the comparative EL element 2. Furthermore, when the initial driving voltage was measured, the EL element 1 showed a value as low as 5.40 V relative to 5.79 V for the comparative EL element 2. Thus, it was confirmed that the EL element of the present invention satisfying formula (a) had higher luminous efficiency and lower driving voltage than the comparative EL element not satisfying formula (a).

[0581] [Chemical formula 54]

[0582]

[0583] Industrial Applicability

[0584] The organic light-emitting element of the present invention can achieve high luminous efficiency while improving the carrier balance and the element life by using two host materials. Therefore, according to the present invention, an organic light-emitting element with excellent practicality can be provided. Therefore, the industrial applicability of the present invention is high.

Claims

1. An organic light-emitting element having a composition comprising a first host material, a second host material having a higher HOMO energy level than the first host material, a delayed fluorescence material and a light-emitting material, and satisfying the following formula (a): E HOMO (H2)-E HOMO (T) ≤ 0.33 eV Equation (a), In the above formula, E HOMO (H2) represents the HOMO energy level of the second host material, and its unit is eV, E HOMO (T) represents the energy level of HOMO of the delayed fluorescent material, and its unit is eV.

2. The organic light emitting element according to claim 1, wherein The first host material, the second host material, the delayed fluorescent material and the light-emitting material satisfy the following formula (b): E HOMO (H1)<E HOMO (H2)≤E HOMO (T)≤E HOMO (E) Formula (b), In formula (b), E HOMO (H1) represents the HOMO energy level of the first host material, E HOMO (H2) represents the HOMO energy level of the second host material, E HOMO (T) represents the energy level of the HOMO of the delayed fluorescent material, E HOMO (E) represents the energy level of HOMO of the light-emitting material.

3. The organic light emitting element according to claim 1, wherein The first host material, the second host material, the delayed fluorescent material and the light-emitting material satisfy the following formula (c): E HOMO (H1)<E HOMO (T)<E HOMO (H2)≤E HOMO (E) Formula (c), In formula (c), E HOMO (H1) represents the HOMO energy level of the first host material, E HOMO (H2) represents the HOMO energy level of the second host material, E HOMO (T) represents the energy level of the HOMO of the delayed fluorescent material, E HOMO (E) represents the energy level of HOMO of the light-emitting material.

4. The organic light emitting element according to any one of claims 1 to 3, wherein The concentration of the first host material in the composition is 0.3 to 3.0 times the concentration of the second host material.

5. The organic light emitting element according to any one of claims 1 to 3, wherein: The first host material and the second host material have a structure represented by any one of the following general formulas (1) to (3), [Chemical formula 1] General formula (1) In the general formula (1), X represents O, S or N (R 6 ), R 1 ~R 5 Each independently represents a deuterium atom or a substituent, R 6 represents a deuterium atom, an alkyl group, an aryl group, or a group composed of an alkyl group and an aryl group, n1 and n2 each independently represent an integer from 0 to 5, n3 represents an integer from 0 to 4, n4 represents an integer from 0 to 2, n5 represents an integer from 0 to 4, and two adjacent R 1 , two adjacent R 2 , two adjacent R 3 , two adjacent R 4 , two adjacent R 5 can bond to each other to form a ring structure, [Chemical formula 2] General formula (2) In the general formula (2), R 11 ~R 13 Each independently represents a deuterium atom or a substituent, n11 to n12 each independently represents an integer from 0 to 5, n13 represents an integer from 1 to 5, and two adjacent R 11 , two adjacent R 12 , two adjacent R 13 can bond to each other to form a ring structure, in which two adjacent R 13 When the two groups are bonded to each other to form a benzofurano structure or a benzothiopheno structure, there is a group containing a dibenzofurano structure or a dibenzothiophene structure or a group containing a cyano group as R 13 , [Chemical formula 3] General formula (3) In the general formula (3), R 21 represents a group containing a dibenzofuran structure, R 22 ~R 24 Each independently represents a deuterium atom or a substituent, n22 to n24 each independently represents an integer from 0 to 4, and two adjacent R 22 , two adjacent R 23 , two adjacent R 24 can bond to each other to form a ring structure, in which two adjacent R 24 When the benzofurano structure or benzothiopheno structure is formed by bonding to each other, there is an aryl group which may be substituted by an alkyl group as R 24 .

6. The organic light emitting element according to claim 5, wherein: The first host material is a compound represented by the general formula (3), and the second host material is a compound represented by the general formula (1) or (2).

7. The organic light emitting element according to claim 5, wherein: The first host material and the second host material are compounds represented by the general formula (3).

8. The organic light emitting element according to any one of claims 1 to 3, wherein: The delayed fluorescent material is a substituted benzonitrile compound or a compound having a phenazine skeleton.

9. The organic light emitting element according to any one of claims 1 to 3, wherein: The organic light-emitting element is an organic electroluminescent element, and the light-emitting layer of the organic electroluminescent element comprises the composition.

10. A method for designing an organic light-emitting element, which is a method for designing an organic light-emitting element having a composition, wherein the composition comprises a first host material, a second host material having a higher HOMO energy level than the first host material, a delayed fluorescent material, and a light-emitting material, wherein: The HOMO energy level of the second host material is HOMO (H2) and the energy level E of the HOMO of the delayed fluorescent material HOMO (T) combining the second host material and the delayed fluorescent material in a manner satisfying the following formula (a), E HOMO (H2)-E HOMO (T) ≤ 0.33 eV Equation (a).

11. A program for implementing the method according to claim 10.

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