Organic electroluminescent element, design method for the same, and program

Abstract

To provide an organic electroluminescent element with a long element life.SOLUTION: The organic electroluminescent element has at least one organic layer including an anode, a cathode, and a light-emitting layer. Further, between the anode and the light-emitting layer, there is an electron barrier layer including an electron barrier material having an electric dipole moment of less than 3.08D.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to an organic electroluminescence element having a long element life, a design method thereof, and a program for carrying out the design method. [Background technology]

[0002] Research into improving the luminous efficiency of organic electroluminescence elements (organic EL elements) is being actively conducted. Among these, there is research into organic electroluminescence elements that improve luminous efficiency by using an electron barrier layer or a hole barrier layer. Here, the electron barrier layer and the hole barrier layer are layers that prevent the electrons and holes present in the luminescent layer from diffusing outside the luminescent layer, and are intended to improve luminous efficiency by increasing the probability of recombination of electrons and holes in the luminescent layer. For example, it has been proposed to use the following compound as a material for the electron blocking layer of such an organic electroluminescence device (see Patent Document 1):

[0003] [ka] [Prior art documents] [Patent documents]

[0004] [Patent Document 1] WO2023 / 053835A1 Summary of the Invention [Problem to be solved by the invention]

[0005] As described above, it has been proposed to use a compound having a dibenzofuryl group and a diphenylcarbazolyl group as a material for the electron blocking layer. However, when the present inventors evaluated the characteristics of an organic electroluminescence element using this electron blocking material, they found that there is room for improvement in the element life.

[0006] Therefore, the present inventors have conducted extensive research with the aim of providing an organic electroluminescence element having an electron blocking layer and / or a hole blocking layer and having a long element life. [Means for solving the problem]

[0007] As a result of intensive research, the present inventors have found that an organic electroluminescence element having a long element life can be provided by using a compound having an electric dipole moment within a specific range in the electron blocking layer or the hole blocking layer. The present invention has been proposed based on this finding, and specifically has the following configuration.

[0008] [1] An organic electroluminescence device having an anode, a cathode, and at least one organic layer including an emitting layer between the anode and the cathode, wherein the organic electroluminescence device has an electron blocking layer between the anode and the emitting layer, the electron blocking layer including an electron blocking material having an electric dipole moment of less than 3.08 D. [2] An organic electroluminescence device having an anode, a cathode, and at least one organic layer including an emitting layer between the anode and the cathode, wherein the organic electroluminescence device has a hole blocking layer between the cathode and the emitting layer, the hole blocking layer including a hole blocking material having an electric dipole moment of less than 6.51 D. [3] The organic electroluminescence device according to [1], further comprising a hole blocking layer between the cathode and the light emitting layer, the hole blocking layer including a hole blocking material having an electric dipole moment of less than 6.51 D. [4] The organic electroluminescence device according to [3], wherein the sum of the electric dipole moment of the electron blocking material and the electric dipole moment of the hole blocking material is less than 3.00 D. [5] The organic electroluminescence device according to [3], wherein the sum of the electric dipole moment of the electron blocking material and the electric dipole moment of the hole blocking material is less than 2.00 D. [6] The organic electroluminescence device according to any one of [1] and [3] to [5], wherein the electron blocking material contains a carbazole ring. [7] The organic electroluminescence device according to any one of [1] and [3] to [6], wherein the electron blocking material contains a dibenzofuran ring or a dibenzothiophene ring. [8] The organic electroluminescence device according to any one of [1] and [3] to [7], wherein the electron blocking material contains a benzofuro-fused carbazole ring or a benzothieno-fused carbazole ring. [9] The organic electroluminescence device according to any one of [1] and [3] to [8], wherein the electron blocking material contains a carbazole ring and a dibenzofuran ring or a dibenzothiophene ring.

[10] The organic electroluminescence device according to [9], wherein the carbazole ring and the dibenzofuran ring or the dibenzothiophene ring are linked via a substituted or unsubstituted phenylene group.

[11] The organic electroluminescence device according to

[10] , wherein the substituted or unsubstituted phenylene group is a substituted or unsubstituted m-phenylene group.

[12] The organic electroluminescence device according to

[10] , wherein the substituted or unsubstituted phenylene group is a substituted or unsubstituted p-phenylene group.

[13] The organic electroluminescence device according to any one of

[10] to

[12] , wherein a substituted or unsubstituted aryl group is bonded to at least one of the carbazole ring, the dibenzofuran ring, and the dibenzothiophene ring in addition to the phenylene group.

[14] The organic electroluminescence device according to any one of [1] to

[13] , wherein the light-emitting layer contains a delayed fluorescent material.

[15] A method for designing an organic electroluminescence device having an anode, a cathode, and an organic layer between the anode and the cathode, the organic layer including, in order from the anode side, an electron blocking layer, an emitting layer, and a hole blocking layer, wherein the electron blocking layer is designed to include an electron blocking material having an electric dipole moment of less than 3.08 D, and the hole blocking layer is designed to include a hole blocking material having an electric dipole moment of less than 6.51 D.

[16] The design method according to

[15] , comprising the steps of: searching a database storing the electric dipole moments of a plurality of materials as data for a material having an electric dipole moment of less than 3.08 D, and selecting an electron blocking material to be used in an organic light-emitting element from a group of materials hit by the search; searching the database for a material having an electric dipole moment of less than 6.51 D, and selecting a hole blocking material to be used in an organic light-emitting element from a group of materials hit by the search; and designing an organic electroluminescence element using the electron blocking material and the hole blocking material selected in the steps.

[17] A method for designing an organic electroluminescence device having an anode, a cathode, and an organic layer between the anode and the cathode, the organic layer including, from the anode side, an electron blocking layer containing an electron blocking material, an emitting layer, and a hole blocking layer containing a hole blocking material, wherein the organic electroluminescence device is designed so that the sum of the electric dipole moment of the electron blocking material and the electric dipole moment of the hole blocking material is less than 3.00 D.

[18] A step of searching a database storing data on the electric dipole moments of a plurality of materials for two materials whose sum of electric dipole moments is less than 3.00 D, and selecting an electron blocking material and a hole blocking material to be used in an organic light-emitting device from a group of combinations of materials found in the search; The design method according to

[17] , further comprising a step of designing an organic electroluminescence element using the electron blocking material and the hole blocking material selected in the step.

[19] A program for carrying out the method according to any one of

[15] to

[18] . Effect of the Invention

[0009] By using an electron blocking material or a hole blocking material whose electric dipole moment is within a specific range according to the present invention, an organic electroluminescence element having a long element life can be realized. Also, by using the design method of the present invention, an organic electroluminescence element having a long element life can be designed. [Brief description of the drawings]

[0010] [Figure 1] 1 is a graph showing the relationship between the electric dipole moment and LT95 of an electron barrier material. [Diagram 2] 1 is a graph showing the relationship between the electric dipole moment of a hole blocking material and LT95. [Diagram 3] 1 is a graph showing the change over time in the luminous intensity of an organic electroluminescence element. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] The contents of the present invention are described in detail below. The following description of the constituent elements may be based on representative embodiments and specific examples of the present invention, but the present invention is not limited to such embodiments and specific examples. In this application, a numerical range expressed using "to" means a range including the numerical values ​​before and after "to" as the lower and upper limits. In addition, in this application, "consists of" means that the compound consists only of what is described before "consists of", and does not include anything else. In addition, some or all of the hydrogen atoms present in the molecules of the compound used in the present invention may be replaced with deuterium atoms ( 2H, deuterium D). In the chemical structural formulas in this specification, hydrogen atoms are represented as H or are omitted. For example, when the atom bonded to the ring-structuring carbon atom of a benzene ring is omitted, H is assumed to be bonded to the ring-structuring carbon atom at the omitted position. In this specification, the term "substituent" means an atom or atomic group other than hydrogen atoms and deuterium atoms. On the other hand, the expressions "substituted or unsubstituted" and "optionally substituted" mean that a hydrogen atom may be substituted with a deuterium atom or a substituent. In addition, "transparent" in the present invention means that the transmittance of visible light is 50% or more, preferably 80% or more, more preferably 90% or more, and even more preferably 99% or more. The transmittance of visible light can be measured by an ultraviolet-visible spectrophotometer.

[0012] <Organic electroluminescence element> The first and second configurations of the organic electroluminescence element of the present invention will be described below. The organic electroluminescent element of the first configuration is an organic electroluminescent element having an anode, a cathode, and at least one organic layer including an emitting layer between the anode and the cathode, and has an electron blocking layer between the anode and the emitting layer, the electron blocking layer including an electron blocking material having an electric dipole moment of less than 3.08 D. In the present invention, the "electron barrier layer" refers to a layer that can prevent electrons present in the light-emitting layer from diffusing to a layer closer to the anode than the light-emitting layer. By having the electron barrier layer, electrons tend to remain in the light-emitting layer, and the probability of recombination of electrons and holes (carriers) can be increased. In the present invention, the electric dipole moment of the electron barrier material used in the electron barrier layer is set to less than 3.08D. The electric dipole moment indicates the degree of charge imbalance in a molecule. The larger this value is, the greater the degree of charge imbalance. The "electric dipole moment" is calculated by the molecular orbital calculation of quantum chemical calculation B3LYP / 6-31G*. In the present invention, by using an electron blocking material with an electric dipole moment of less than 3.08 D, i.e., an electron blocking material with a relatively small degree of charge imbalance, it is possible to realize an organic electroluminescence element with a long element life and suppressed change in luminous intensity over time. This is presumably due to the following reasons. That is, the electron barrier layer also has the function of transporting holes injected from the anode side into the electron barrier layer to the light-emitting layer side and injecting them into the light-emitting layer. Here, the larger the electric dipole moment of the electron barrier material, the easier the hole injection from the electron barrier layer to the light-emitting layer tends to proceed, and the position of the carrier recombination region is closer to the cathode side. On the other hand, in the continuous operation of an element having an electron barrier layer, the electron barrier material gradually deteriorates as the operation time accumulates, causing changes in its molecular size and charge state. At this time, the electron barrier material that originally has a large electric dipole moment has a large degree of change in electric dipole moment due to such changes in molecular size and charge state, so that the position of the carrier recombination region also shifts significantly due to the influence, and the change in the light-emitting characteristics over time is also considered to be large. In contrast, in the present invention, an electron barrier material with an electric dipole moment of less than 3.08D is used, so even if the electron barrier material deteriorates to a certain extent due to the accumulation of operation time, the degree of change in its electric dipole moment is small. It is therefore presumed that the carrier recombination region does not fluctuate significantly, and the change in emission intensity over time is also kept small.

[0013] The organic electroluminescent device of the first configuration preferably further comprises a hole blocking layer between the cathode and the light emitting layer, the hole blocking layer comprising a hole blocking material having an electric dipole moment of less than 6.51 D. In this specification, the term "hole blocking layer" refers to a layer that can prevent holes present in the light-emitting layer from diffusing to a layer on the cathode side of the light-emitting layer. By providing a hole blocking layer together with an electron blocking layer, both electrons and holes tend to remain in the light-emitting layer, and the probability of recombination of electrons and holes can be increased. If a hole blocking material having an electric dipole moment of less than 6.51 D is used as the material for this hole blocking layer, the change in luminescence intensity over time can be more reliably suppressed, and the life of the organic electroluminescence element can be further improved. In a configuration in which an electron blocking layer and a hole blocking layer are provided, the sum of the electric dipole moment of the electron blocking material and the electric dipole moment of the hole blocking material is preferably less than 3.00 D, more preferably less than 2.00 D. As a combination of materials that results in a sum of electric dipole moments of less than 3.00D, the combination of compound EB1 and any of compounds HB1 to HB4, the combination of compound EB2 and any of compounds HB1 to HB4, the combination of compound EB3 and any of compounds HB1 to HB4, the combination of compound EB5 and compound HB3 or HB4, and the combination of compound EB6 and any of compounds HB1 to HB4, which are used in the examples shown below, can be mentioned. As a combination of materials that results in a sum of electric dipole moments of less than 2.00D, the combination of compound EB1 and any of compounds HB2 to HB4, the combination of compound EB2 and any of compounds HB2 to HB4, the combination of compound EB3 and compound HB3 or HB4, and the combination of compound EB6 and compounds HB2 to HB4 can be mentioned. Here, compounds EB1 to EB3, EB5, and EB6 are electron blocking materials, and compounds HB1 to HB4 are hole blocking materials. However, the combination of electron blocking materials and hole blocking materials that can be adopted in the present invention is not limited to these specific examples.

[0014] Next, the organic electroluminescent element of the second configuration of the present invention will be described. The organic electroluminescent element of the second configuration is an organic electroluminescent element having an anode, a cathode, and at least one organic layer including an emitting layer between the anode and the cathode, and has a hole blocking layer between the cathode and the emitting layer, the hole blocking layer including a hole blocking material having an electric dipole moment of less than 6.51 D. For an explanation of the hole blocking layer and the hole blocking material having an electric dipole moment of less than 6.51 D, please refer to the description of the "hole blocking layer" provided as necessary in the above-mentioned first configuration. In the organic electroluminescence device of the second configuration, the electric dipole moment of the hole blocking material is relatively small, so that the shift of the carrier recombination region caused by the deterioration of the hole blocking material is thought to be suppressed to a small extent, and the device exhibits a long life. The organic electroluminescent element of the second configuration may or may not have an electron blocking layer between the anode and the light emitting layer. When the electron blocking layer is present, the material thereof may be appropriately selected from known electron blocking materials.

[0015] The electron blocking material used in the first configuration of the present invention, and the hole blocking material used in the first and second configurations of the present invention will be described in detail below.

[0016] (Electron Barrier Materials) In a first aspect of the present invention, an electron barrier material is used having an electric dipole moment of less than 3.08 D. The electric dipole moment of the electron barrier material is preferably less than 2.20 D, more preferably less than 1.25 D, and even more preferably less than 1.00 D. The electron barrier material used in the present invention preferably has an electric dipole moment of less than 3.08 D and an absolute value of the LUMO (Lowest Unoccupied Molecular Orbital) energy smaller than that of the material of the light-emitting layer. This effectively prevents the electrons present in the light-emitting layer from diffusing to a layer closer to the anode than the light-emitting layer. Specifically, it is preferable that the absolute value of the LUMO energy of the electron barrier material and the absolute value of the LUMO energy of the light-emitting layer satisfy the following relationship. |LUMO| EB <|LUMO| EM -α E In the formula, |LUMO| EB represents the absolute value of the LUMO energy of the electron barrier material, and |LUMO| EM represents the absolute value of the LUMO energy of the material of the emitting layer, and the unit is eV. E represents a number of 0.64 or more, preferably 0.80 or more, and more preferably 0.94 or more. When the light-emitting layer is made of only a light-emitting material, the absolute value of the LUMO energy of the light-emitting material is |LUMO| EM When the light-emitting layer contains multiple materials, the absolute value of the LUMO energy of the material responsible for electronic conduction is |LUMO| EM For example, when the light-emitting layer contains a light-emitting material (delayed fluorescent material) and a host material, the absolute value of the LUMO energy of the light-emitting material (delayed fluorescent material) is |LUMO| EM This applies. In this specification, the LUMO energy is determined by calculating the electron energy from the absorption peak edge of a thin film containing the material to be measured, and calculating the difference between this and the HOMO energy calculated by photoelectron collection spectroscopy in air.

[0017] The electron blocking material used in the present invention can be selected from a group of compounds containing, for example, a carbazole ring. The carbazole ring contained in the electron blocking material may be condensed with another ring to form a condensed polycyclic structure. The explanation of the ring condensed to the carbazole ring, the preferred range, and specific examples are given in the R 11 and R12 The description of the ring structure formed by bonding each other can be referred to. In the following description, a carbazole ring to which another ring is not condensed may be referred to as a "non-condensed carbazole ring", and a carbazole ring to which another ring is condensed may be referred to as a "condensed carbazole ring". Preferred examples of the condensed carbazole ring include a benzofuro-condensed carbazole ring and a benzothieno-condensed carbazole ring. In the benzofuro-condensed carbazole ring, the condensation position of the benzofuro structure may be any of the 1,2-position, 2,3-position, and 3,4-position of the carbazole ring. In the benzothieno-condensed carbazole ring, the condensation position of the benzothieno structure may be any of the 1,2-position, 2,3-position, and 3,4-position of the carbazole ring. An example of a compound containing a carbazole ring is a compound represented by the following general formula (1): In one embodiment of the present invention, an electron blocking material is selected from the group of compounds represented by the following general formula (1).

[0018] [ka]

[0019] In the general formula (1), R 1a represents a substituent, R 11 ~R 18 R each independently represents a hydrogen atom, a deuterium atom, or a substituent. 11 ~R 18 may be the same or different from each other. R 1aThe substituent represented by is preferably a substituted or unsubstituted aryl group, more preferably a substituted or unsubstituted phenyl group. Preferred examples of the substituent of the aryl group and the phenyl group include a group containing a dibenzofuran ring or a dibenzothiophene ring and a group containing a non-condensed carbazole ring, and are preferably a substituted or unsubstituted dibenzofuryl group and a substituted or unsubstituted dibenzothienyl group. The dibenzofuryl group may be any of a dibenzofuran-1-yl group, a dibenzofuran-2-yl group, a dibenzofuran-3-yl group, and a dibenzofuran-4-yl group, and is preferably a dibenzofuran-2-yl group. The dibenzothienyl group may be any of a dibenzothiophene-1-yl group, a dibenzothiophene-2-yl group, a dibenzothiophene-3-yl group, and a dibenzothiophene-4-yl group, and is preferably a dibenzothiophene-2-yl group. Examples of the substituents of the dibenzofuryl group and the dibenzothienyl group include the groups in the following Substituent Group B, and are preferably substituted or unsubstituted aryl groups (the substituents are, for example, the groups in the Substituent Group B), and more preferably are groups selected from the group consisting of aryl groups having 6 to 10 carbon atoms or groups combining two or more aryl groups having 6 to 10 carbon atoms. In a preferred embodiment of the present invention, R 1a is a phenyl group substituted with a substituted or unsubstituted dibenzofuran-2-yl group, more preferably a phenyl group substituted with a dibenzofuran-2-yl group substituted with a substituted or unsubstituted aryl group, or a phenyl group substituted with an unsubstituted dibenzofuran-2-yl group. 1a is a phenyl group substituted with a substituted or unsubstituted dibenzothiophen-2-yl group, more preferably a phenyl group substituted with a dibenzothiophen-2-yl group substituted with a substituted or unsubstituted aryl group, or a phenyl group substituted with an unsubstituted dibenzothiophen-2-yl group. R 11 ~R 18Examples of the substituent that R may have include the groups in the following Substituent Group B, and preferably, one or a combination of two or more groups selected from the group consisting of aryl groups (e.g., having 6 to 10 carbon atoms) and carbazolyl groups. 11 ~R 18 is a group selected from the group consisting of a hydrogen atom, a deuterium atom, an aryl group having 6 to 10 carbon atoms, or a group consisting of a combination of two or more aryl groups having 6 to 10 carbon atoms. 13 and R 16 In a more preferred embodiment of the present invention, one of R is a group selected from the group consisting of an aryl group having 6 to 10 carbon atoms or a group consisting of a combination of two or more aryl groups having 6 to 10 carbon atoms, and the other is a hydrogen atom or a deuterium atom. 11 ~R 18 Of these, R 13 and R 16 Only one of the groups is an aryl group having 6 to 10 carbon atoms, or a group selected from the group consisting of a combination of two or more aryl groups having 6 to 10 carbon atoms, and the remaining group is a hydrogen atom or a deuterium atom. In this specification, the "combination of two or more aryl groups having 6 to 10 carbon atoms" refers to, for example, a group having a structure in which two or more aryl groups are linked by a single bond, and specific examples include a biphenyl group and a terphenyl group. R 11 and R 12 , R 12 and R 13 , R 13 and R 14 , R 14 and R 15 , R 15 and R 16 , R 16 and R 17 , R 17 and R 18may be bonded to each other to form a cyclic structure. The cyclic structure formed by bonding to each other may be an aromatic ring or an aliphatic ring, may contain a heteroatom, and may further be a condensed ring of two or more rings. The heteroatom referred to here is preferably one selected from the group consisting of a nitrogen atom, an oxygen atom, and a sulfur atom. Examples of the cyclic structure formed include a benzene ring, a naphthalene ring, a phenanthrene ring, a triphenylene ring, a pyridine ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring, a pyrrole ring, an imidazole ring, a pyrazole ring, an imidazoline ring, an oxazole ring, an isoxazole ring, a thiazole ring, an isothiazole ring, a cyclohexadiene ring, a cyclohexene ring, a cyclopentaene ring, a cycloheptatriene ring, a cycloheptadiene ring, a furan ring, a thiophene ring, a naphthyridine ring, a quinoxaline ring, a quinoline ring, a benzofuran ring, and a benzothiophene ring, and the like can be mentioned, and the benzofuran ring and the benzothiophene ring are particularly preferred. The number of rings contained in the group represented by the general formula (1) may be selected from the range of 3 to 5, or may be selected from the range of 5 to 7.

[0020] Preferred examples of the compound represented by general formula (1) include compounds represented by any of the following general formulae (2) to (7).

[0021] [ka]

[0022] In the general formulas (2) to (7), R 2a ~R 7a represents a substituent, R 21 ~R 80 R each independently represents a hydrogen atom, a deuterium atom, or a substituent. 21 ~R 80 may be the same or different. 2a ~R 7a The preferred range and specific examples of the substituent represented by R in the above general formula (1) are 1a Please refer to the description of R 21~R 80 Examples of the substituent that can be taken by X include the groups in the following Substituent Group B, and preferred are groups selected from the group consisting of aryl groups having 6 to 10 carbon atoms or groups combining two or more aryl groups having 6 to 10 carbon atoms. 2 ~X 7 represents an oxygen atom or a sulfur atom. In one embodiment of the present invention, X 2 ~X 7 is an oxygen atom. In one embodiment of the present invention, X 2 ~X 7 is a sulfur atom. In a preferred embodiment of the present invention, the electron blocking material is selected from the group of compounds represented by general formula (2). 28 and R 29 At least one of R is preferably an aryl group having 6 to 10 carbon atoms or a group selected from the group consisting of a combination of two or more aryl groups having 6 to 10 carbon atoms, 28 It is more preferable that R is a group selected from the group consisting of an aryl group having 6 to 10 carbon atoms or a group consisting of a combination of two or more aryl groups having 6 to 10 carbon atoms. 21 ~R 30 Among these, the remainder, excluding an aryl group having 6 to 10 carbon atoms or a combination of two or more aryl groups having 6 to 10 carbon atoms, is preferably a hydrogen atom or a deuterium atom.

[0023] Examples of the compound represented by general formula (1) include compounds represented by the following formula: 1a However, the substituted or unsubstituted non-condensed carbazolyl group and the substituted or unsubstituted condensed carbazolyl group that can be used in the present invention should not be construed as being limited by these specific examples. a R represents a substituent. a The preferred range and specific examples of the substituent represented by R in the above general formula (1) are 1a Please refer to the description of.

[0024] [ka]

[0025] The number of carbazole rings contained in the molecule of the electron-blocking material may be one or more. When the electron-blocking material contains two or more carbazole rings in the molecule, the carbazole rings may be condensed with another ring or may be the same or different from each other in the type of the condensed other ring. In one embodiment of the present invention, the electron-blocking material is selected from a group of compounds containing one carbazole ring in the molecule. In one embodiment of the present invention, the electron-blocking material is selected from a group of compounds containing two or more carbazole rings in the molecule, and preferably, the electron-blocking material is selected from a group of compounds containing two or three carbazole rings in the molecule. In a preferred embodiment of the present invention, the electron-blocking material is selected from a group of compounds containing one benzofuro-fused carbazole ring or one benzothieno-fused carbazole ring in the molecule.

[0026] The electron barrier material used in the present invention can be selected from a group of compounds containing, for example, a dibenzofuran ring or a dibenzothiophene ring. In this specification, the "dibenzofuran ring" and "dibenzothiophene ring" do not include the "dibenzofuran ring" (dibenzofuran unit) and "dibenzothiophene ring" (dibenzothiophene unit) contained in a fused carbazole ring. Therefore, for example, the dibenzofuran unit contained in a benzofuro-fused carbazole ring and the dibenzothiophene unit contained in a benzothieno-fused carbazole ring do not fall under the "dibenzofuran ring" and "dibenzothiophene ring" herein. An example of a compound containing a dibenzofuran ring or a dibenzothiophene ring is a compound represented by the following general formula (8): In one embodiment of the present invention, an electron blocking material is selected from the group of compounds represented by the following general formula (8).

[0027] [ka]

[0028] In the general formula (8), R 81 ~R 88 each independently represents a hydrogen atom, a deuterium atom, or a substituent; R 81 ~R 88 At least one of R is a substituent. 81 ~R 88 At least one of is preferably a substituted or unsubstituted aryl group, and more preferably a substituted or unsubstituted phenyl group. Preferred examples of the substituents of the aryl group and the phenyl group include a group containing a carbazole ring (non-condensed carbazole ring or condensed carbazole ring). For an explanation of the carbazole ring of the group containing a carbazole ring (non-condensed carbazole ring or condensed carbazole ring), the description of "carbazole ring" in the above "compound containing a carbazole ring" can be referred to. Examples of the group containing a carbazole ring (non-condensed carbazole ring or condensed carbazole ring) include R 1a ~R 7a , R a Examples of the substituents are monovalent groups in which the "substituents" are replaced with "bonding positions." In one embodiment of the present invention, R 81 is a phenyl group substituted with a group containing a carbazole ring (a non-condensed carbazole ring or a condensed carbazole ring). 82 is a phenyl group substituted with a group containing a carbazole ring (a non-condensed carbazole ring or a condensed carbazole ring). 83 is a phenyl group substituted with a group containing a carbazole ring (a non-condensed carbazole ring or a condensed carbazole ring). 84 R is a phenyl group substituted with a group containing a carbazole ring (either a non-condensed carbazole ring or a condensed carbazole ring). 81 ~R 88Among these, except for those which are phenyl groups substituted with a group containing a carbazole ring (non-condensed carbazole ring or condensed carbazole ring), the rest may all be hydrogen atoms or deuterium atoms, or at least one may be a substituent. Examples of the substituent include groups in the following Substituent Group B, and are preferably substituted or unsubstituted aryl groups (the substituents are, for example, groups in the Substituent Group B), more preferably aryl groups having 6 to 10 carbon atoms, or groups selected from the group consisting of a combination of two or more aryl groups having 6 to 10 carbon atoms. In a preferred embodiment of the present invention, R in the general formula (8) 83 is a phenyl group substituted with a group containing a carbazole ring (a non-condensed carbazole ring or a condensed carbazole ring), and R 86 is a group selected from the group consisting of an aryl group having 6 to 10 carbon atoms or a group consisting of a combination of two or more aryl groups having 6 to 10 carbon atoms.

[0029] The number of dibenzofuran rings or dibenzothiophene rings contained in the molecule of the electron barrier material may be one or more. In one embodiment of the present invention, the electron barrier material is selected from a group of compounds having one dibenzofuran ring in the molecule. In one embodiment of the present invention, the electron barrier material is selected from a group of compounds having two or more dibenzofuran rings in the molecule, preferably, the electron barrier material is selected from a group of compounds having two or three dibenzofuran rings in the molecule. In one embodiment of the present invention, the electron barrier material is selected from a group of compounds having one dibenzothiophene ring in the molecule. In one embodiment of the present invention, the electron barrier material is selected from a group of compounds having two or more dibenzothiophene rings in the molecule, preferably, the electron barrier material is selected from a group of compounds having two or three dibenzothiophene rings in the molecule.

[0030] The electron barrier material used in the present invention is preferably selected from a group of compounds containing a carbazole ring (non-condensed carbazole ring or condensed carbazole ring) and a dibenzofuran ring or a dibenzothiophene ring in the molecule. For an explanation of the carbazole ring (non-condensed carbazole ring or condensed carbazole ring), the description of "carbazole ring" in the above "compound containing a carbazole ring" can be referred to. Examples of the compound include, for example, compounds represented by general formulas (1) to (7) in which R 1a ~R 7a , R a is a phenyl group substituted with a group containing a dibenzofuran ring or a dibenzothiophene ring, and among the compounds represented by the general formula (8), R 81 ~R 88 At least one of the groups may be a phenyl group substituted with a group containing a carbazole ring (a non-condensed carbazole ring or a condensed carbazole ring). When the electron barrier material contains a carbazole ring (a non-fused carbazole ring or a fused carbazole ring) and a dibenzofuran ring or a dibenzothiophene ring in the molecule, the number of each ring contained in the molecule may be one or two or more. In a preferred embodiment of the present invention, the electron barrier material contains one carbazole ring (non-fused carbazole ring or fused carbazole ring) and one dibenzofuran ring in the molecule. In one embodiment of the present invention, the electron barrier material contains two or more carbazole rings (non-fused carbazole ring or fused carbazole ring) and one dibenzofuran ring in the molecule, preferably two or three carbazole rings (non-fused carbazole ring or fused carbazole ring) and one dibenzofuran ring in the molecule. In one embodiment of the present invention, the electron barrier material contains one carbazole ring (non-fused carbazole ring or fused carbazole ring) and two or more dibenzofuran rings in the molecule, preferably one carbazole ring (non-fused carbazole ring or fused carbazole ring) and two or three dibenzofuran rings in the molecule. In one embodiment of the present invention, the electron barrier material contains two or more carbazole rings (either non-fused carbazole rings or fused carbazole rings) and two or more dibenzofuran rings in the molecule, and preferably contains two or three carbazole rings (either non-fused carbazole rings or fused carbazole rings) and two or three dibenzofuran rings in the molecule. In a preferred embodiment of the present invention, the electron barrier material contains one carbazole ring (non-fused carbazole ring or fused carbazole ring) and one dibenzothiophene ring in the molecule. In one embodiment of the present invention, the electron barrier material contains two or more carbazole rings (non-fused carbazole ring or fused carbazole ring) and one dibenzothiophene ring in the molecule, preferably two or three carbazole rings (non-fused carbazole ring or fused carbazole ring) and one dibenzothiophene ring in the molecule. In one embodiment of the present invention, the electron barrier material contains one carbazole ring (non-fused carbazole ring or fused carbazole ring) and two or more dibenzothiophene rings in the molecule, preferably one carbazole ring (non-fused carbazole ring or fused carbazole ring) and two or three dibenzothiophene rings in the molecule. In one embodiment of the present invention, the electron barrier material contains two or more carbazole rings (either non-fused carbazole rings or fused carbazole rings) and two or more dibenzothiophene rings in the molecule, and preferably contains two or three carbazole rings (either non-fused carbazole rings or fused carbazole rings) and two or three dibenzothiophene rings in the molecule.

[0031] More preferably, the electron barrier material used in the present invention is selected from a group of compounds having a structure in which a carbazole ring (non-condensed carbazole ring or condensed carbazole ring) and a dibenzofuran ring or a dibenzothiophene ring are linked by a substituted or unsubstituted phenylene group. The phenylene group may be any of 1,2-phenylene, 1,3-phenylene, and 1,4-phenylene. It is preferably a 1,3-phenylene group (m-phenylene group) or a 1,4-phenylene group (p-phenylene group), and more preferably 1,3-phenylene. The substituent of the phenylene group may be a group of the following substituent group B, and is preferably a group selected from the group consisting of an aryl group having 6 to 10 carbon atoms or a group consisting of a combination of two or more aryl groups having 6 to 10 carbon atoms. The bonding position to the phenylene group in the carbazole ring (non-condensed carbazole ring or condensed carbazole ring) is preferably the N-position (the 9th position in the carbazole ring). The bonding position of the phenylene group in the dibenzofuran ring or dibenzothiophene ring may be any of the 1st to 4th positions, but is preferably the 2nd position. In addition, in a structure in which a carbazole ring (non-condensed carbazole ring or condensed carbazole ring) and a dibenzofuran ring or a dibenzothiophene ring are linked by a substituted or unsubstituted phenylene group, a substituted or unsubstituted aryl group is preferably bonded to at least one of the carbazole ring (non-condensed carbazole ring or condensed carbazole ring), dibenzofuran ring, and dibenzothiophene ring, in addition to the phenylene group, and more preferably a substituted or unsubstituted aryl group is bonded to at least the carbazole ring (non-condensed carbazole ring or condensed carbazole ring). The substituted or unsubstituted aryl group is preferably an aryl group (e.g., having 6 to 30 carbon atoms) which may be substituted with a group of the substituent group B, and more preferably a group selected from the group consisting of an aryl group having 6 to 10 carbon atoms or a group in which two or more aryl groups having 6 to 10 carbon atoms are combined. A preferred example of the compound in which a carbazole ring (a non-condensed carbazole ring or a condensed carbazole ring) and a dibenzofuran ring or a dibenzothiophene ring are linked via a substituted or unsubstituted phenylene group is a compound represented by the following general formula (9), and a more preferred embodiment is a compound represented by the following general formula (10).

[0032] [ka]

[0033] In the general formulas (9) and (10), R 11 ~R 18 , R 21 ~R 30 , R 81 , R 82 , R 84 ~R 88 R each independently represents a hydrogen atom, a deuterium atom, or a substituent. 11 ~R 18 For the explanation, see R in the above general formula (1). 11 ~R 18 Please refer to the description of R 21 ~R 30 For the explanation, see R in the above general formula (7). 21 ~R 30 Please refer to the description of R 81 , R 82 , R 84 ~R 88 For the explanation, see R in the above general formula (8). 81 , R 82 , R 84 ~R 88 Please refer to the description of R 101 represents a deuterium atom or a substituent, and n101 represents an integer of 0 to 4. 2 and X 8 represents an oxygen atom or a sulfur atom. In one embodiment of the present invention, X 2 and X 8 is an oxygen atom. In one embodiment of the present invention, X 2 and X 8 is a sulfur atom. X2 or X 8 The fused ring group having the formula (dibenzofuryl group, dibenzothienyl group) is preferably bonded to the 3- or 4-position of the phenylene group, and more preferably bonded to the 3-position. In the compound represented by the general formula (9), R 11 ~R 18 , R 81 , R 82 , R 84 ~R 88 At least one of R is preferably a substituted or unsubstituted aryl group, and in the compound represented by the general formula (10), 21 ~R 30 , R 81 , R 82 , R 84 ~R 88 It is preferable that at least one of the substituted or unsubstituted aryl groups is a substituted or unsubstituted aryl group. The substituted or unsubstituted aryl group in the general formulae (9) and (10) is preferably an aryl group (e.g., having 6 to 30 carbon atoms) which may be substituted with a group of the substituent group B, and more preferably an aryl group having 6 to 10 carbon atoms or a group formed by combining two or more aryl groups having 6 to 10 carbon atoms. In a preferred embodiment of the present invention, the electron blocking material is represented by the general formula (9), 11 ~R 18 is a substituted or unsubstituted aryl group. 13 and R 16 It is preferable that one of R is a substituted or unsubstituted aryl group and the other is a hydrogen atom or a deuterium atom. 11 ~R 18 Of these, R 13 and R 16 It is more preferable that only one of the groups is a substituted or unsubstituted aryl group, and the rest are all hydrogen atoms or deuterium atoms. In one embodiment of the present invention, the electron blocking material is represented by the general formula (9), 81 , R 82 , R 84 ~R 88 is a substituted or unsubstituted aryl group.86 is preferably a substituted or unsubstituted aryl group, and R 11 ~R 18 Of these, R 86 It is more preferable that only is a substituted or unsubstituted aryl group, and the rest are all hydrogen atoms or deuterium atoms. In a preferred embodiment of the present invention, the electron blocking material is represented by the general formula (10), 21 ~R 30 is a substituted or unsubstituted aryl group. 28 and R 29 It is preferable that at least one of R is a substituted or unsubstituted aryl group. 28 More preferably, R is a substituted or unsubstituted aryl group. 21 ~R 30 Among these, the remainder, excluding those which are substituted or unsubstituted aryl groups, are preferably hydrogen atoms or deuterium atoms. In one embodiment of the present invention, the electron blocking material is represented by the general formula (10), 81 , R 82 , R 84 ~R 88 is a substituted or unsubstituted aryl group. 86 is preferably a substituted or unsubstituted aryl group, and R 11 ~R 18 Of these, R 86 It is more preferable that only is a substituted or unsubstituted aryl group, and the rest are all hydrogen atoms or deuterium atoms.

[0034] Specific examples of compounds that can be used as electron blocking materials are given below, but the compounds that can be used as electron blocking materials in the present invention should not be construed as being limited to these specific examples.

[0035] [ka] JPEG2024171218000008.jpg219170JPEG2024171218000009.jpg132170

[0036] (Hole blocking material) A preferred embodiment of the present invention uses a hole blocking material having an electric dipole moment of less than 6.51 D. The electric dipole moment of the hole blocking material is preferably less than 2.00 D, more preferably less than 1.00 D, and particularly preferably less than 0.50 D. The hole blocking material used in the present invention preferably has an electric dipole moment of less than 6.51 D and an absolute value of HOMO energy greater than that of the material of the light emitting layer. This effectively prevents holes in the light emitting layer from diffusing to a layer closer to the cathode than the light emitting layer. Specifically, it is preferable that the absolute value of the HOMO energy of the hole blocking material and the absolute value of the HOMO energy of the light emitting layer satisfy the following relationship: |HOMO| EM +α H <|HOMO| HB In the formula, |HOMO| HB represents the absolute value of the HOMO (Highest Occupied Molecular Orbital) energy of the hole-blocking material, and |HOMO| EM represents the absolute value of the HOMO energy of the material of the light-emitting layer, and the unit is eV. H represents a number of -0.13 or more, preferably 0.10 or more, and more preferably 0.37 or more. When the light-emitting layer is made of only a light-emitting material, the absolute value of the HOMO energy of the light-emitting material is |HOMO| EM When the light-emitting layer contains a light-emitting material and a host material, the absolute value of the HOMO energy of the host material is |HOMO| EM This applies. Herein, the HOMO energies are determined by photoelectron collection spectroscopy in air.

[0037] The hole blocking material used in the present invention can be selected from a group of compounds containing, for example, a 6-membered nitrogen-containing aromatic heterocycle (hereinafter referred to as "nitrogen-containing aromatic heterocycle"). Examples of the nitrogen-containing aromatic heterocycle include a pyridine ring, a pyrazine ring, a pyrimidine ring, a pyridazine ring, and a triazine ring. The triazine ring may be any of a 1,2,3-triazine ring, a 1,2,4-triazine ring, and a 1,3,5-triazine ring, and is preferably a 1,3,5-triazine ring.

[0038] An example of a compound containing a nitrogen-containing aromatic heterocyclic 6-membered ring is a compound represented by the following general formula (11): In one embodiment of the present invention, a hole blocking material is selected from the group of compounds represented by general formula (11).

[0039] [ka]

[0040] In the general formula (11), R 91 ~R 93 each independently represents a substituent; A 1 ~A 3 are each independently N or C(R 94 ), and R 94 represents a hydrogen atom, a deuterium atom or a substituent. 1 ~A 3 At least one of is N. 91 ~R 93 may be the same or different. 94 When there are multiple R 94 may be the same or different from each other. R 91 ~R 93The substituent represented by is preferably a substituted or unsubstituted aryl group, more preferably a substituted or unsubstituted phenyl group. Examples of the substituent of the aryl group and the phenyl group include the groups of the substituent group A and the substituent group D, and are preferably a group containing a fused ring containing two or more benzene rings (hereinafter referred to as a "fused aromatic ring"). For an explanation of the fused aromatic ring, the description of the "fused aromatic ring" in the "Compound containing a fused ring (fused aromatic ring) containing two or more benzene rings" below can be referred to. Examples of the group containing a fused aromatic ring include a monovalent group in which one hydrogen atom has been removed from a fused aromatic ring, and a monovalent group in which one hydrogen atom has been removed from a linking structure in which two or more fused aromatic rings are linked by a single bond. In addition, the R in each formula representing the "Examples of compounds containing a fused aromatic ring" below can be used. b A specific example of the group containing a condensed aromatic ring is a monovalent group in which the "substituent" in the above formula is replaced with the "bonding position". In one aspect of the invention, R 91 ~R 93 In a preferred embodiment of the present invention, one of X is a phenyl group substituted with a group containing a fused aromatic ring group, and the remaining two are unsubstituted phenyl groups. 1 ~X 3 is N and R 91 ~R 93 In one embodiment of the present invention, one of R is a phenyl group substituted with a group containing a fused aromatic ring group, and the remaining two are unsubstituted phenyl groups. 91 ~R 93 In a preferred embodiment of the present invention, two of X are phenyl groups substituted with a group containing a fused aromatic ring group, and the remaining one is an unsubstituted phenyl group. 1 ~X 3 is N and R 91 ~R 93 Two of the groups are phenyl groups substituted with a group containing a fused aromatic ring group, and the remaining one is an unsubstituted phenyl group.

[0041] The number of nitrogen-containing aromatic heterocyclic rings contained in the hole-blocking material in the molecule may be one or more. When the hole-blocking material contains two or more nitrogen-containing aromatic heterocyclic rings in the molecule, the nitrogen-containing aromatic heterocyclic rings may be the same or different from each other. In one embodiment of the present invention, the hole-blocking material is selected from a group of compounds containing one nitrogen-containing aromatic heterocyclic ring in the molecule. In one embodiment of the present invention, the hole-blocking material is selected from a group of compounds containing two or more nitrogen-containing aromatic heterocyclic rings in the molecule, and preferably, the hole-blocking material is selected from a group of compounds containing two or three nitrogen-containing aromatic heterocyclic rings in the molecule.

[0042] The hole blocking material used in the present invention can also be selected from a group of compounds containing a fused ring (fused aromatic ring) containing, for example, two or more benzene rings. The condensed aromatic ring may be one having only a benzene ring as a constituent ring, or one containing a ring other than a benzene ring as a constituent ring. The constituent ring other than the benzene ring constituting the condensed aromatic ring may be either an aromatic ring or an aliphatic ring, and may contain a heteroatom. The heteroatom is preferably an oxygen atom or a sulfur atom. The number of benzene rings contained in the condensed aromatic ring is preferably 2 to 5, and for example, 2 or 3 can be selected. The number of rings constituting the condensed aromatic ring is preferably 2 to 6, and for example, can be selected from 2 to 4. Specific examples of the condensed aromatic ring include a naphthalene ring, a fluorene ring, an anthracene ring, a phenanthrene ring, a triphenylene ring, a dibenzofuran ring, and a dibenzothiophene ring. The number of condensed aromatic rings contained in the hole blocking material in the molecule may be one or more than two. When the hole blocking material contains two or more condensed aromatic rings in the molecule, the condensed aromatic rings may be the same or different from each other. The two or more condensed aromatic rings can have a linking structure, for example, linked by a single bond. The number of linked condensed aromatic rings is preferably 2 to 5, more preferably 2 or 3. An example of a preferred linking structure is a structure in which a naphthalene ring and an anthracene ring are linked by a single bond. In one embodiment of the present invention, the hole blocking material is selected from a group of compounds containing one condensed aromatic ring in the molecule. In one embodiment of the present invention, the hole blocking material is selected from a group of compounds containing two or more condensed aromatic rings in the molecule, and preferably, the hole blocking material is selected from a group of compounds having two or three condensed aromatic rings in the molecule. In a preferred embodiment of the present invention, the hole blocking material is selected from a group of compounds having a structure in which a naphthalene ring and an anthracene ring are linked by a single bond.

[0043] Examples of compounds containing fused aromatic rings include compounds represented by the following formula: In one embodiment of the present invention, the hole blocking material is selected from the group of compounds represented by the following formula: b R represents a substituent. b The substituent represented by is preferably a substituted or unsubstituted aryl group, more preferably a substituted or unsubstituted phenyl group. The substituent of the phenyl group is preferably a group containing a nitrogen-containing aromatic hetero six-membered ring (for example, a monovalent group obtained by removing one hydrogen atom from a nitrogen-containing aromatic hetero six-membered ring) or a group containing the above-mentioned condensed aromatic ring (for example, a monovalent group obtained by removing one hydrogen atom from a condensed aromatic ring). For an explanation of the nitrogen-containing aromatic hetero six-membered ring, the description of the "nitrogen-containing aromatic hetero six-membered ring" in the above-mentioned compound containing a nitrogen-containing aromatic hetero six-membered ring can be referred to. The condensed aromatic ring, R b At least one hydrogen atom of the group containing a fused aromatic ring and the group containing a nitrogen-containing aromatic hetero 6-membered ring may be substituted with a substituent. Examples of the substituent include groups of Substituent Group A and Substituent Group D, and a group containing a fused aromatic ring or a phenyl group substituted with a group containing a fused aromatic ring is preferable.

[0044] [ka]

[0045] The hole blocking material used in the present invention is preferably selected from a group of compounds containing a nitrogen-containing aromatic hetero six-membered ring and a fused aromatic ring in the molecule. For an explanation of the nitrogen-containing aromatic hetero six-membered ring, the description of the "nitrogen-containing aromatic hetero six-membered ring" in the compound containing a nitrogen-containing aromatic hetero six-membered ring above can be referred to, and for an explanation of the fused aromatic ring, the description of the "fused aromatic ring" in the compound containing a fused ring (fused aromatic ring) containing two or more benzene rings above can be referred to. Examples of the compound include the compound represented by the above general formula (11), in which R 91 ~R 93 is a substituted or unsubstituted phenyl group, R 91 ~R 93 In one or two of the above, the substituent of the phenyl group is a group containing a condensed aromatic ring. In one embodiment of the present invention, the hole blocking material contains one nitrogen-containing aromatic six-membered ring and one fused aromatic ring in the molecule. In one embodiment of the present invention, the hole blocking material contains one nitrogen-containing aromatic six-membered ring and two or more fused aromatic rings in the molecule, more preferably one nitrogen-containing aromatic six-membered ring and two or three fused aromatic rings in the molecule.

[0046] More preferably, the hole blocking material used in the present invention is selected from a group of compounds having a structure in which a fused aromatic ring is connected to a nitrogen-containing aromatic hetero 6-membered ring via a substituted or unsubstituted phenylene group. The number of fused aromatic rings connected to one nitrogen-containing aromatic hetero 6-membered ring via a substituted or unsubstituted phenylene group is preferably one or two. The phenylene group may be any of a 1,2-phenylene group, a 1,3-phenylene group, and a 1,4-phenylene group. A 1,3-phenylene group or a 1,4-phenylene group is preferable. In addition, a substituted or unsubstituted phenyl group is preferably bonded to at least one of the ring skeleton carbon atoms of the nitrogen-containing aromatic hetero 6-membered ring, in addition to the phenylene group linking the fused aromatic ring, and an unsubstituted phenyl group is more preferable. An example of a compound having a structure in which a fused aromatic ring is linked to a nitrogen-containing aromatic heterocycle via a substituted or unsubstituted phenylene group is a compound represented by the following general formula (12).

[0047] [ka]

[0048] In the general formula (12), R 101 ~R 115 each independently represents a hydrogen atom, a deuterium atom, or a substituent; R 101 ~R 115 At least one of the groups is a group containing a fused aromatic ring. Examples of the substituent include groups in the substituent group A and the substituent group D. For an explanation of the fused aromatic ring of the group containing a fused aromatic ring, the description of the "fused aromatic ring" in the above "Compound containing a fused ring (fused aromatic ring) containing two or more benzene rings" can be referred to. Examples of the group containing a fused aromatic ring include a monovalent group obtained by removing one hydrogen atom from a fused aromatic ring, and a monovalent group obtained by removing one hydrogen atom from a linking structure in which two or more (preferably two or three) fused aromatic rings are linked by a single bond. In addition, R in each formula shown above as "Examples of compounds containing a fused aromatic ring" can be used. bis substituted with "bonding position", as a specific example of the group containing a condensed aromatic ring. In one embodiment of the present invention, the hole blocking material is represented by the general formula (12), 101 ~R 105 is a compound in which at least one of R is a group containing a condensed aromatic ring, and preferably R 102 and R 103 At least one of R is a group containing a condensed aromatic ring, and more preferably R 102 and R 103 Only one of R is a group containing a condensed aromatic ring. 101 ~R 115 Among these, it is preferred that all of the remaining groups, except for the group containing a condensed aromatic ring, are hydrogen atoms or deuterium atoms. In one embodiment of the present invention, the hole blocking material is represented by the general formula (12), 101 ~R 105 At least one of and R 106 ~R 110 is a compound in which at least one of R is a group containing a condensed aromatic ring, and preferably R 102 and R 103 At least one of and R 107 and R 108 At least one of R is a group containing a condensed aromatic ring, and more preferably R 102 and R 103 Only one of these and R 107 and R 108 Only one of R is a group containing a condensed aromatic ring. 101 ~R 115 Among these, it is preferred that all of the remaining groups, except for the group containing a condensed aromatic ring, are hydrogen atoms or deuterium atoms.

[0049] Specific examples of compounds that can be used as hole blocking materials are given below, but the compounds that can be used as hole blocking materials in the present invention should not be construed as being limited to these specific examples.

[0050] [ka]

[0051] In the present specification, the "alkyl group" may be linear, branched, or cyclic. In addition, two or more of the linear, cyclic, and branched portions may be mixed. The number of carbon atoms of the alkyl group may be, for example, 1 or more, 2 or more, or 4 or more. In addition, the number of carbon atoms may be 30 or less, 20 or less, 10 or less, 6 or less, or 4 or less. Specific examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, an n-pentyl group, an isopentyl group, an n-hexyl group, an isohexyl group, a 2-ethylhexyl group, an n-heptyl group, an isoheptyl group, an n-octyl group, an isooctyl group, an n-nonyl group, an isononyl group, an n-decanyl group, an isodecanyl group, a cyclopentyl group, a cyclohexyl group, and a cycloheptyl group. The alkyl group as a substituent may be further substituted with an aryl group. The "alkenyl group" may be linear, branched, or cyclic. In addition, two or more of the linear, cyclic, and branched portions may be mixed. The number of carbon atoms in the alkenyl group may be, for example, 2 or more, 4 or more. In addition, the number of carbon atoms may be 30 or less, 20 or less, 10 or less, 6 or less, or 4 or less. Specific examples of the alkenyl group include ethenyl, n-propenyl, isopropenyl, n-butenyl, isobutenyl, n-pentenyl, isopentenyl, n-hexenyl, isohexenyl, and 2-ethylhexenyl. The alkenyl group as a substituent may be further substituted with a substituent. The "aryl group" and the "heteroaryl group" may be a single ring or a fused ring in which two or more rings are fused. In the case of a fused ring, the number of fused rings is preferably 2 to 6, and can be selected from, for example, 2 to 4. Specific examples of the ring include a benzene ring, a pyridine ring, a pyrimidine ring, a triazine ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, a triphenylene ring, a quinoline ring, a pyrazine ring, a quinoxaline ring, and a naphthyridine ring, and these may be fused rings. Specific examples of the aryl group or the heteroaryl group include a phenyl group, a 1-naphthyl group, a 2-naphthyl group, a 1-anthracenyl group, a 2-anthracenyl group, a 9-anthracenyl group, a 2-pyridyl group, a 3-pyridyl group, and a 4-pyridyl group. The number of atoms constituting the ring skeleton of the aryl group is preferably 6 to 40, more preferably 6 to 20, and may be selected within the range of 6 to 14 or 6 to 10. The number of atoms constituting the ring skeleton of the heteroaryl group is preferably 4 to 40, more preferably 5 to 20, and may be selected from the range of 5 to 14, or from the range of 5 to 10. For the "arylene group" and "heteroaryl group", the valence in the explanation of the aryl group and heteroaryl group can be changed from 1 to 2.

[0052] In the present specification, the term "substituent group A" refers to 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 heteroaryl It means one group or a combination of two or more groups selected from the group consisting of an arylthio group (e.g., having 5 to 30 ring skeleton atoms), an acyl group (e.g., having 1 to 40 carbon atoms), an alkenyl group (e.g., having 1 to 40 carbon atoms), an alkynyl group (e.g., having 1 to 40 carbon atoms), an alkoxycarbonyl group (e.g., having 1 to 40 carbon atoms), an aryloxycarbonyl group (e.g., having 1 to 40 carbon atoms), a heteroaryloxycarbonyl group (e.g., having 1 to 40 carbon atoms), a silyl group (e.g., a trialkylsilyl group having 1 to 40 carbon atoms), a nitro group, and a cyano group. In this specification, "substituent group B" means one group or a combination of two or more groups selected from the group consisting of alkyl groups (e.g., having 1 to 40 carbon atoms), alkoxy groups (e.g., having 1 to 40 carbon atoms), aryl groups (e.g., having 6 to 30 carbon atoms), aryloxy groups (e.g., having 6 to 30 carbon atoms), heteroaryl groups (e.g., having 5 to 30 ring skeleton atoms), heteroaryloxy groups (e.g., having 5 to 30 ring skeleton atoms), and diarylamino groups (e.g., having 12 to 20 carbon atoms). In this specification, the "substituent group C" refers to one group or a combination of two or more groups selected from the group consisting of alkyl groups (e.g., having 1 to 20 carbon atoms), aryl groups (e.g., having 6 to 22 carbon atoms), heteroaryl groups (e.g., having 5 to 20 ring skeleton atoms), and diarylamino groups (e.g., having 12 to 20 carbon atoms). In this specification, the term "substituent group D" refers to one group or a combination of two or more groups selected from the group consisting of alkyl groups (e.g., having 1 to 20 carbon atoms), aryl groups (e.g., having 6 to 22 carbon atoms) and heteroaryl groups (e.g., having 5 to 20 ring skeleton atoms). In this specification, the term "substituent group E" refers to one group or a combination of two or more groups selected from the group consisting of alkyl groups (eg, having 1 to 20 carbon atoms) and aryl groups (eg, having 6 to 22 carbon atoms). In the present specification, the substituent referred to as a "substituent" or "substituted or unsubstituted" may be selected, for example, from Substituent Group A, or may be selected from Substituent Group B, or may be selected from Substituent Group C, or may be selected from Substituent Group D, or may be selected from Substituent Group E.

[0053] As used herein, the lowest excited singlet energy (E S1 ) and the lowest excited triplet energy (E T1 ) is a value calculated by the following procedure. ST E S1 -E T1 This value was obtained by calculating (1) The lowest excited singlet energy (E S1 ) A thin film or toluene solution of the compound to be measured (concentration 10 -5 A sample is prepared by preparing a solution of 100 mol / L. The fluorescence spectrum of this sample is measured at room temperature (300K). The fluorescence spectrum has emission on the vertical axis and wavelength on the horizontal axis. A tangent line is drawn to the rising edge of the short wavelength side of this emission spectrum, and the wavelength value λedge [nm] at the intersection of this tangent line and the horizontal axis is calculated. This wavelength value is converted to an energy value using the following conversion formula, and the value is called E S1 Let us assume that. Conversion formula: E S1 [eV]=1239.85 / λedge The emission spectra in the examples described later were measured using an LED light source (M300L4, manufactured by Thorlabs) as the excitation light source and a detector (PMA-12 multichannel spectrometer C10027-01, manufactured by Hamamatsu Photonics KK). (2) The lowest excited triplet energy (E T1 ) The lowest excited singlet energy (E S1The same sample used in the measurement of phosphorescence is cooled to 77[K] with liquid nitrogen, and the sample for phosphorescence measurement is irradiated with excitation light (300 nm) and the phosphorescence is measured using a detector. The emission from 100 milliseconds after irradiation with excitation light is taken as the phosphorescence spectrum. A tangent line is drawn to the rising edge of the short wavelength side of this phosphorescence spectrum, and the wavelength value λedge[nm] at the intersection of this tangent line and the horizontal axis is calculated. This wavelength value is converted to an energy value using the following conversion formula and is called E T1 Let us assume that. Conversion formula: E T1 [eV]=1239.85 / λedge The tangent to the rising edge of the phosphorescence spectrum on the short wavelength side is drawn as follows. When moving along the spectral curve from the short wavelength side of the phosphorescence spectrum to the shortest maximum of the spectral maxima, consider the tangent at each point on the curve toward the long wavelength side. The slope of this tangent increases as the curve rises (i.e., as the vertical axis increases). The tangent drawn at the point where this slope is at its maximum value is considered to be the tangent to the rising edge of the phosphorescence spectrum on the short wavelength side. Note that a maximum point having a peak intensity of 10% or less of the maximum peak intensity of the spectrum is not included in the maximum value on the shortest wavelength side described above, and the tangent drawn at the point where the slope value is the maximum value that is closest to the maximum value on the shortest wavelength side is regarded as the tangent to the rising edge on the short wavelength side of the phosphorescence spectrum.

[0054] [Overall structure of organic electroluminescence element] The overall configuration of the organic electroluminescence element according to the first and second configurations of the present invention will be described below. The organic electroluminescence element to which the present invention is applied 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 in the first configuration of the present invention includes an electron blocking layer disposed between the anode and the light-emitting layer in addition to the light-emitting layer, and the electron blocking layer includes an electron blocking material having an electric dipole moment of less than 3.08 D. The organic electroluminescence device of the first configuration includes an electron blocking layer having an electric dipole moment of less than 3.08 D, i.e., an electron blocking material having a relatively small electric dipole moment, so that the change in the emission intensity over time is suppressed and the device has a long life. In one embodiment of the present invention, the electron blocking layer is provided between the anode and the light-emitting layer and adjacent to the light-emitting layer. The organic layer in the first configuration of the present invention may be composed of only the light-emitting layer and the electron blocking layer, or may have one or more organic layers in addition to the light-emitting layer and the electron blocking layer. In a preferred embodiment of the first configuration, the organic layer further includes a hole blocking layer disposed between the cathode and the light-emitting layer, and the hole blocking layer includes a hole blocking material having an electric dipole moment of less than 6.51 D. In one embodiment of the present invention, the hole blocking layer is provided between the cathode and the light emitting layer and adjacent to the light emitting layer. The organic layer in the first configuration of the present invention may further include other organic layers. Such other organic layers may include a hole transport layer, a hole injection layer, an electron injection layer, an electron transport layer, an exciton blocking layer, etc. The organic layer in the second configuration of the present invention includes a hole blocking layer disposed between the cathode and the light emitting layer in addition to the light emitting layer, and the hole blocking layer includes a hole blocking material having an electric dipole moment of less than 6.51 D. In the organic electroluminescence device of the second configuration, the electron blocking layer includes a hole blocking material having an electric dipole moment of less than 6.51 D, i.e., a hole blocking material having a relatively small electric dipole moment, so that the change in the emission intensity over time is suppressed and the device has a long life. In one embodiment of the present invention, the hole blocking layer is provided between the cathode and the light emitting layer and adjacent to the light emitting layer. The organic layer in the second configuration of the present invention may be composed of only the light emitting layer and the hole blocking layer, or may have one or more organic layers in addition to the light emitting layer and the hole blocking layer. Examples of such other organic layers include a hole transport layer, a hole injection layer, an electron blocking layer, an electron injection layer, an electron transport layer, and an exciton blocking layer. In the first and second configurations of the present invention, the hole transport layer may be a hole injection transport layer having a hole injection function, and the electron transport layer may be an electron injection transport layer having an electron injection function. The organic electroluminescent element of the first and second configurations of the present invention may have a substrate supporting an anode, a cathode, and an organic layer (at least one of an emitting layer, an electron blocking layer, and a hole blocking layer). In this case, the substrate may be disposed on the anode opposite the emitting layer, or on the cathode opposite the emitting layer. The organic electroluminescent element of the present invention may be a top emission type element in which most of the light is emitted from the side opposite the substrate, or a bottom emission type element in which most of the light is emitted from the substrate side. Here, "most of the light" means that the amount of light emitted from the element is 60% or more.

[0055] Each component and each layer of the organic electroluminescence element will be described below. For the description of the electron blocking material and hole blocking material used in the first configuration and the hole blocking material used in the second configuration, please refer to the descriptions in the above (electron blocking material) and (hole blocking material) columns.

[0056] Base material: In some embodiments, the organic electroluminescent device of the present invention is supported by a substrate, which is not particularly limited and may be any material commonly used in organic electroluminescent devices, such as glass, transparent plastic, quartz, and silicon.

[0057] anode: In some embodiments, the anode of the organic electroluminescent device is made of a metal, an alloy, a conductive compound, or a combination thereof. In some embodiments, the metal, alloy, or conductive compound has a high work function (4 eV or more). In some embodiments, the metal is Au. In some embodiments, the conductive transparent material is selected from CuI, indium tin oxide (ITO), SnO2, and ZnO. In some embodiments, an amorphous material capable of forming a transparent conductive film, such as IDIXO (In2O3-ZnO), is used. 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 a photolithographic method. In some embodiments, if the pattern does not need to be highly accurate (e.g., about 100 μm or more), the pattern may be formed using a mask with a shape suitable for evaporation or sputtering on the electrode material. In some embodiments, when a coating material, such as an organic conductive compound, can be applied, a wet film formation method, such as a printing method or a coating method, is used. In some embodiments, the anode has a transmittance of more than 10% when emitted light passes through the anode, and the anode has a sheet resistance of several hundred ohms per unit area or less. In some embodiments, the anode has a thickness of 10 to 1,000 nm. In some embodiments, the anode has a thickness of 10 to 200 nm. In some embodiments, the thickness of the anode varies depending on the material used.

[0058] cathode: In some embodiments, the cathode is made of an electrode material such as a metal with a low work function (4 eV or less) (referred to as an electron-injecting metal), an alloy, a conductive compound, or a combination thereof. In some embodiments, the electrode material is selected from sodium, sodium-potassium alloy, magnesium, lithium, magnesium-copper mixture, magnesium-silver mixture, magnesium-aluminum mixture, magnesium-indium mixture, aluminum-aluminum oxide (Al2O3) mixture, indium, lithium-aluminum mixture, and rare earth elements. In some embodiments, a mixture of an electron-injecting metal and a second metal, which is a stable metal having a higher work function than the electron-injecting metal, is used. In some embodiments, the mixture is selected from magnesium-silver mixture, magnesium-aluminum mixture, magnesium-indium mixture, aluminum-aluminum oxide (Al2O3) mixture, lithium-aluminum mixture, and aluminum. In some embodiments, the mixture improves electron-injecting properties and resistance to oxidation. In some embodiments, the cathode is manufactured by forming the electrode material as a thin film by evaporation or sputtering. In some embodiments, the cathode has a sheet resistance of several hundred ohms or less per unit area. In some embodiments, the cathode has a thickness of 10 nm to 5 μm. In some embodiments, the cathode has a thickness of 50 to 200 nm. In some embodiments, one of the anode and cathode of the organic electroluminescent device is transparent or semi-transparent to transmit emitted light. In some embodiments, a transparent or semi-transparent electroluminescent device improves light radiance. In some embodiments, the cathode is formed from a conductive, transparent material as described above for the anode, thereby forming a transparent or semi-transparent cathode, hi some embodiments, an element includes an anode and a cathode, both of which are transparent or semi-transparent.

[0059] Emitting layer: In some embodiments, the light-emitting layer is a layer in which holes and electrons injected from the anode and cathode, respectively, recombine to form excitons, hi some embodiments, the layer emits light. In some embodiments, only the light-emitting material is used as the light-emitting layer. In some embodiments, in order to improve the light emission efficiency of the organic electroluminescent device, the singlet and triplet excitons generated in the light-emitting material are trapped in the light-emitting material. In some embodiments, a host material is used in the light-emitting layer in addition to the light-emitting material. In some embodiments, the host material is an organic compound. In some embodiments, the organic compound has an excited singlet energy and an excited triplet energy, at least one of which is higher than those of the light-emitting material. In some embodiments, the singlet and triplet excitons generated in the light-emitting material are trapped in the molecules of the light-emitting material. In some embodiments, the singlet and triplet excitons are sufficiently trapped to improve the light emission efficiency. In some embodiments, the singlet and triplet excitons are not sufficiently trapped, i.e., the host material with high light emission efficiency that can be used in the present invention is not particularly limited. In some embodiments, light emission occurs in the light-emitting material in the light-emitting layer of the device of the present invention. In some embodiments, the emitted light includes both fluorescence and delayed fluorescence. In some embodiments, the emitted light includes phosphorescence. In some embodiments, the emitted light includes fluorescence but not delayed fluorescence. In some embodiments, the emitted light includes emitted light from a host material. In some embodiments, the emitted light consists of emitted light from a host material. In some embodiments, the emitted light includes emitted light from an emitting material and emitted light from a host material. In some embodiments, TADF molecules and a host material are used. In some embodiments, TADF is an assist dopant. In some embodiments, the emitting layer includes an assist dopant along with one or more emitting materials and one or more host materials.

[0060] In some embodiments, when a host material is used, the amount of emissive material in the light-emitting layer is 0.1 wt% or more. In some embodiments, when a host material is used, the amount of emissive material in the light-emitting layer is 1 wt% or more. In some embodiments, when a host material is used, the amount of emissive material in the light-emitting layer is 50 wt% or less. In some embodiments, when a host material is used, the amount of emissive material in the light-emitting layer is 20 wt% or less. In some embodiments, when a host material is used, the amount of emissive material in the light-emitting layer is 10 wt% or less. In some embodiments, the host material of the light-emitting layer is an organic compound that has hole transport and electron transport functions. In some embodiments, the host material of the light-emitting layer is an organic compound that prevents the wavelength of emitted light from increasing. In some embodiments, the host material of the light-emitting layer is an organic compound that has a high glass transition temperature.

[0061] In one embodiment, the light-emitting layer contains two or more types of TADF molecules with different structures. For example, the light-emitting layer may contain three materials, the host material, the first TADF molecule, and the second TADF molecule, whose excited singlet energy levels are higher in this order. In this case, the first TADF molecule and the second TADF molecule both have a difference ΔE between the lowest excited singlet energy level and the lowest excited triplet energy level of 77K. STis preferably 0.3 eV or less, more preferably 0.25 eV or less, more preferably 0.2 eV or less, more preferably 0.15 eV or less, even more preferably 0.1 eV or less, even more preferably 0.07 eV or less, even more preferably 0.05 eV or less, even more preferably 0.03 eV or less, and particularly preferably 0.01 eV or less. The content of the first TADF molecule in the light-emitting layer is preferably greater than the content of the second TADF molecule. The content of the host material in the light-emitting layer is preferably greater than the content of the second TADF molecule. The content of the first TADF molecule in the light-emitting layer may be greater than, less than, or the same as the content of the host material. In an embodiment, the composition in the light-emitting layer may be 10 to 70 wt % of the host material, 10 to 80 wt % of the first TADF molecule, and 0.1 to 30 wt % of the second TADF molecule. In an embodiment, the composition in the light-emitting layer may be 20 to 45% by weight of the host material, 50 to 75% by weight of the first TADF molecule, and 5 to 20% by weight of the second TADF molecule. In an embodiment, the light emission quantum yield φPL1(A) by light excitation of the co-deposited film of the first TADF molecule and the host material (content of the first TADF molecule in this co-deposited film = A weight %) and the light emission quantum yield φPL2(A) by light excitation of the co-deposited film of the second TADF molecule and the host material (content of the second TADF molecule in this co-deposited film = A weight %) satisfy the relational expression φPL1(A) > φPL2(A). In an embodiment, the light emission quantum yield φPL2(B) by light excitation of the co-deposited film of the second TADF molecule and the host material (content of the second TADF molecule in this co-deposited film = B weight %) and the light emission quantum yield φPL2(100) by light excitation of the single film of the second TADF molecule satisfy the relational expression φPL2(B) > φPL2(100). In some embodiments, the light-emitting layer can contain three structurally different TADF molecules. The compound of the present invention can be any of the TADF compounds contained in the light-emitting layer.

[0062] In some embodiments, the light-emitting layer can be made of a material selected from the group consisting of a host material, an assist dopant, and a light-emitting material. In some embodiments, the light-emitting layer does not contain a metal element. In some embodiments, the light-emitting layer can be made of a material consisting of only atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms, oxygen atoms, and sulfur atoms. Alternatively, the light-emitting layer can be made of a material consisting of only atoms selected from the group consisting of carbon atoms, hydrogen atoms, and nitrogen atoms.

[0063] The light-emitting material may be a TADF molecule (delayed fluorescent material), a fluorescent material that does not emit delayed fluorescence, or a phosphorescent material. In this specification, a "fluorescent material" is a light-emitting material whose fluorescent emission intensity is higher than the phosphorescent emission intensity when the light emission is observed at 20°C, and a "phosphorescent material" is a light-emitting material whose phosphorescent emission intensity is higher than the fluorescent emission intensity when the light emission is observed at 20°C. In addition, a "delayed fluorescent material" is a material in which both fluorescence with a short emission lifetime and fluorescence with a long emission lifetime (delayed fluorescence) are observed at 20°C. Since normal fluorescence (fluorescence that is not delayed fluorescence) has an emission lifetime on the order of ns, and phosphorescence usually has an emission lifetime on the order of ms, fluorescence and phosphorescence can be distinguished by their emission lifetimes. In addition, luminescent organic compounds other than organometallic complexes are normal fluorescent materials or delayed fluorescent materials. As the fluorescent material, anthracene derivatives, tetracene derivatives, naphthacene derivatives, pyrene derivatives, perylene derivatives, chrysene derivatives, rubrene derivatives, coumarin derivatives, pyran derivatives, stilbene derivatives, fluorene derivatives, anthryl derivatives, pyrromethene derivatives, terphenyl derivatives, terphenylene derivatives, fluoranthene derivatives, amine derivatives, quinacridone derivatives, oxadiazole derivatives, malononitrile derivatives, pyran derivatives, carbazole derivatives, julolidine derivatives, thiazole derivatives, derivatives having metals (Al, Zn), and the like can be used. These exemplary skeletons may or may not have a substituent. These exemplary skeletons may also be combined with each other.

[0064] As the TADF molecule, a known TADF molecule can be used. Preferred TADF molecules include those described in paragraphs 0008 to 0048 and 0095 to 0133 of WO2013 / 154064, paragraphs 0007 to 0047 and 0073 to 0085 of WO2013 / 011954, paragraphs 0007 to 0033 and 0059 to 0066 of WO2013 / 011955, and paragraph 0008 of WO2013 / 081088. JP 2013-256490 A, paragraphs 0009 to 0046 and 0093 to 0134; JP 2013-116975 A, paragraphs 0008 to 0020 and 0038 to 0040; WO 2013 / 133359 A, paragraphs 0007 to 0032 and 0079 to 0084; WO 2013 / 161437 A, paragraph 0 JP 2014-9352 A, paragraphs 0007-0041 and 0060-0069, JP 2014-9224 A, paragraphs 0008-0048 and 0067-0076, JP 2017-119663 A, paragraphs 0013-0025, JP 2017-119664 A, paragraphs 0013-0026, JP 2017-119664 A, The compounds included in the general formulas described in paragraphs 0012 to 0025 of JP 017-222623 A, paragraphs 0010 to 0050 of JP 2017-226838 A, paragraphs 0012 to 0043 of JP 2018-100411 A, and paragraphs 0016 to 0044 of WO 2018 / 047853 A, particularly the example compounds, which are capable of emitting delayed fluorescence, are included.In addition, the following publications are included herein: JP2013-253121A, WO2013 / 133359A, WO2014 / 034535A, WO2014 / 115743A, WO2014 / 122895A, WO2014 / 126200A, WO2014 / 136758A, WO2014 / 133121A, WO20 14 / 136860, WO2014 / 196585, WO2014 / 189122, WO2014 / 168101, WO2015 / 008 580 publication, WO2014 / 203840 publication, WO2015 / 002213 publication, WO2015 / 016200 publication, WO2015 / 019725 publication, WO2015 / 072470, WO2015 / 108049, WO2015 / 080182, WO2015 / 072537, WO2015 / 080183, JP2015-129240A, WO2015 / 129714A, WO2015 / 129715A, WO2015 / 13350 The luminescent materials described in WO2015 / 136880, WO2015 / 137244, WO2015 / 137202, WO2015 / 137136, WO2015 / 146541, and WO2015 / 159541, which can emit delayed fluorescence, can be preferably used. The above publications described in this paragraph are hereby incorporated by reference as part of this specification. These TADF molecules may be used as assist dopants.

[0065] The following are preferred compounds for use as TADF molecules in the present invention, but the TADF molecules that can be used in the present invention should not be construed as being limited to the following compounds. In the following compounds, t-Bu represents a tert-butyl group, and Ph represents a phenyl group. [ka] JPEG2024171218000015.jpg219167JPEG2024171218000016.jpg55166

[0066] In the present invention, a compound represented by the following general formula (13) can also be used as the light emitting material. [ka]

[0067] In the general formula (13), X 1 and X 2 is a nitrogen atom on one side and a boron atom on the other side. 1 ~R 26 , A 1 , A 2 R each independently represents a hydrogen atom, a deuterium atom, or a substituent. 1 and R 2 , R 2 and R 3 , R 3 and R 4 , R 4 and R 5 , R 5 and R 6 , R 6 and R 7 , R 7 and R 8 , R 8 and R 9 , R 9 and R 10 , R 10 and R 11 , R 11 and R 12 , R 13 and R 14 , R 14 and R 15 , R 15 and R 16 , R 16 and R 17 , R 17 and R 18 , R 18 and R 19 , R 19 and R 20 , R 20 and R 21 , R 21 and R 22 , R 22 and R 23 , R 23 and R 24 , R 24 and R 25 , R25 and R 26 may be bonded to each other to form a cyclic structure. 1 is a nitrogen atom, R 17 and R 18 are bonded to each other to form a single bond to form a pyrrole ring, and X 2 is a nitrogen atom, R 21 and R 22 are bonded to each other to form a single bond to form a pyrrole ring. 1 is a nitrogen atom, and R 7 and R 8 and R 21 and R 22 are bonded via a nitrogen atom to form a six-membered ring, and R 17 and R 18 When they are bonded together to form a single bond, R 1 ~R 6 At least one of 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 are bonded to each other to form an aromatic ring or a heteroaromatic ring. 1 is a boron atom, and X 2 is a nitrogen atom, and R 7 and R 8 , R 17 and R 18 When they are bonded to each other to form a ring structure containing a boron atom, the ring structure is a 5- to 7-membered ring, and when it is a 6-membered ring, R 7 and R 8 , R 17 and R 18 are bonded to each other to form -B(R 32 )-, -CO-, -CS- or -N(R 27 )- is formed. R 27 represents a hydrogen atom, a deuterium atom, or a substituent. For details and preferred ranges of the general formula (13), as well as specific examples of compounds included in the general formula (13), reference can be made to paragraphs 0006 to 0128 of WO2022 / 270354A1, which is incorporated herein by reference.

[0068] Among the compounds represented by the general formula (13), the compound represented by the following general formula (13a) can be preferably used because it has excellent properties. [ka]

[0069] In the general formula (13a), R 1 ~R 14 , R 16 , R 19 ~R 31 , A 1 , A 2 R each independently represents a hydrogen atom, a deuterium atom, or a substituent. 1 and R 2 , R 2 and R 3 , R 3 and R 4 , R 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 19 and R 20 , R 20 and R 21 , R 22 and R 23 , R 23 and R 24 , R 24 and R 25 , R 25 and R 26 , R 27 and R 28 , R 28 and R 29, R 29 and R 30 , R 30 and R 31 may be bonded to each other to form a cyclic structure. 1 ~R 14 , R 16 , R 19 ~R 26 , A 1 , A 2 For the description and preferred range of R in the general formula (13), reference can be made to the corresponding description of the general formula (13a). 27 ~R 31 The description and preferred range of R in general formula (13) 8 ~R 12 Reference may be made to the corresponding description in Preferably, R in the general formula (13a) 1 ~R 14 , R 16 , R 19 ~R 31 , A 1 , A 2 each independently represents a hydrogen atom, a deuterium atom, or an alkyl group, and R 3 may be an aryl group optionally substituted with an alkyl group, in which case R 27 ~R 31 At least one, preferably two or more of R represent an alkyl group. 8 ~R 12 , R 22 ~R 26 At least two, preferably at least four, for example at least six of these are alkyl groups, e.g., R 8 , R 10 , R 12 , R 22 , R 24 , R 26 is an alkyl group. The alkyl group here is, for example, a methyl group, an isobutyl group, or a tert-butyl group, for example, an isobutyl group. In another more preferred embodiment, R 27 ~R 31 At least one, preferably two or more, for example three of the following are alkyl groups, e.g., R 28 , R 30is an alkyl group, or R 27 , R 29 , R 31 may be an alkyl group. The alkyl group here is, for example, a methyl group, an isobutyl group, or a tert-butyl group, for example, an isobutyl group, for example, a tert-butyl group. In yet another more preferred embodiment, R 3 is an aryl group substituted with at least one, preferably two or more, for example, three, alkyl groups. For example, R is a phenyl group substituted with a methyl group, an isobutyl group, or a tert-butyl group. 27 ~R 31 You can also refer to the above explanation and preferred ranges for the phenyl group substituted with R 3 It is also preferred that R is a hydrogen atom or a deuterium atom. 1 , R 2 , R 4 ~R 7 , R 13 , R 14 , R 16 , R 19 ~R 21 , A 1 , A 2 are each independently a hydrogen atom or a deuterium atom. In addition, the alkyl group and the aryl group in this paragraph may each have at least one hydrogen atom substituted with a deuterium atom. Specific examples of the compound represented by general formula (13a) are given below, but the compounds represented by general formula (13a) that can be used in the present invention should not be construed as being limited to these specific examples. [ka]

[0070] In the present invention, the light-emitting material is X 1 N, X 2 is B and R 12 and A 1 are bonded to each other to form a linking group represented by -O- or -S-, and R 26 and A 2Compounds having a structure in which R are bonded to each other to form a linking group represented by -O- or -S- can also be preferably used. Compounds that satisfy such conditions are referred to as compounds of general formula (13b). R in general formula (13b) 1 ~R 11 , R 13 ~R 25 At least one of R is a substituent, and examples of such a substituent include a substituted or unsubstituted alkyl group and a substituted or unsubstituted diarylamino group. In a preferred embodiment, the substitution position is R 3 , R 6 , R 9 , R 15 , R 20 , R 23 The number of atoms selected from the group consisting of is one or more, preferably two or more, for example, four or more, and may be six, and the rest may be hydrogen atoms or deuterium atoms. Specific examples of the compound of general formula (13b) are given below, but the compounds of general formula (13b) that can be used in the present invention are not to be construed as being limited to these specific examples. [ka]

[0071] In the present invention, a compound represented by the following general formula (14) can also be used as the light emitting material. [ka]

[0072] In the general formula (14), Ar 1represents a cyclic structure, and is a benzene ring, a naphthalene ring, an anthracene ring, or a phenanthrene ring. D represents a group represented by the following general formula (15). A represents one group selected from the group consisting of a cyano group, a phenyl group, a pyrimidyl group, a triazyl group, and an alkyl group, or a group consisting of a combination of two or more groups (excluding substituted alkyl groups). m is 1 or 2, and n is 0, 1, or 2. When m is 2, the two Ds may be the same or different. When n is 2, the two As may be the same or different. R 1 ~R 4 R each independently represents a hydrogen atom, a deuterium atom, or one or a combination of two or more groups selected from the group consisting of an alkyl group, an aryl group, a heteroaryl group, and a cyano group. 1 and R 2 , R 3 and R 4 may be bonded to each other to form a cyclic structure selected from the group consisting of a benzene ring, a naphthalene ring, and a pyridine ring, and the cyclic structure thus formed may be substituted with one group or a combination of two or more groups selected from the group consisting of an alkyl group, an aryl group, a heteroaryl group, and a cyano group. [ka] In the general formula (15), R 5 ~R 15 R each independently represents a hydrogen atom, a deuterium atom, or a substituent. 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 12 and R 13 , R 13 and R 14 , R 14 and R 15 may be bonded to each other to form a ring structure. X represents a single bond, an oxygen atom or a sulfur atom. * represents the bonding position. For details and preferred ranges of the general formula (14), as well as specific examples of compounds included in the general formula (14), reference can be made to paragraphs 0006 to 0057 of WO2022 / 168956A1, which is incorporated herein by reference as part of this specification.

[0073] Among the compounds represented by the general formula (14), the compound represented by the following general formula (14a) can be preferably used because it has excellent properties. [ka]

[0074] In the general formula (14a), R 5 ~R 38 R each independently represents a hydrogen atom, a deuterium atom, or one or a combination of two or more groups selected from the group consisting of an alkyl group, an aryl group, a heteroaryl group, and a cyano group. 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 12 and R 13 , R 13 and R 14 , R 14 and R 15 may be bonded to each other to form a cyclic structure. 5 ~R 15 For the description and preferred range of R in the general formula (14), reference can be made to the corresponding description of the general formula (14a). 16 ~R 38 preferably each independently represents a hydrogen atom, a deuterium atom, an alkyl group or an aryl group. Preferably, R in the general formula (14a) 5 ~R 38 At least one, preferably 5 or more, for example 10 or more of the R 23 ~R 27, R 30 ~R 34 At least one, preferably 5 or more, for example 10, of R are deuterium atoms. More preferably, R 5 ~R 9 , R 11 ~R 38 are each independently a hydrogen atom, a deuterium atom, or an alkyl group, for example a hydrogen atom or a deuterium atom. 10 is a hydrogen atom or a deuterium atom. 10 is one group selected from the group consisting of an alkyl group, an aryl group, a heteroaryl group, and a cyano group, or a combination of two or more groups, such as a cyano group. Note that the alkyl group and the aryl group in the explanation of general formula (14a) may each have at least one hydrogen atom substituted with a deuterium atom. Specific examples of the compound represented by general formula (14a) are given below, but the compounds represented by general formula (14a) that can be used in the present invention should not be construed as being limited to these specific examples. [ka]

[0075] In some embodiments, the host material is selected from the group consisting of the following compounds: [ka] JPEG2024171218000026.jpg132155

[0076] Injection layer: An injection layer is a layer between an electrode and an organic layer. In some embodiments, the injection layer reduces driving voltage and enhances light radiance. In some embodiments, the injection layer comprises a hole injection layer and an electron injection layer. The injection layer can be disposed between the anode and the 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, an injection layer is present. In some embodiments, an injection layer is not present. Preferred examples of compounds that can be used as the hole injection material are given below.

[0077] [ka]

[0078] Next, preferred examples of compounds that can be used as the electron injection material will be given. [ka]

[0079] Barrier layer: A barrier layer is a layer that can prevent charges (electrons or holes) and / or excitons present in the light-emitting layer from diffusing outside the light-emitting layer. In some embodiments, an electron barrier layer is present between the light-emitting layer and the hole transport layer and prevents electrons from passing through the light-emitting layer to the hole transport layer. In some embodiments, a hole barrier layer is present between the light-emitting layer and the electron transport layer and prevents holes from passing through the light-emitting layer to the electron transport layer. In some embodiments, a barrier layer prevents excitons from diffusing outside the light-emitting layer. In some embodiments, the electron barrier layer and the hole barrier layer constitute an exciton barrier layer. As used herein, the term "electron barrier layer" or "exciton barrier layer" includes layers that have both the functions of an electron barrier layer and of an exciton barrier layer.

[0080] Hole blocking layer: The hole blocking layer functions as an electron transport layer. In some embodiments, the hole blocking layer prevents holes from reaching the electron transport layer during electron transport. In some embodiments, the hole blocking layer increases the probability of recombination of electrons and holes in the light-emitting layer. In a preferred embodiment of the first configuration of the present invention and the organic electroluminescent device of the second configuration of the present invention, the hole blocking layer comprises a hole blocking material having an electric dipole moment of less than 6.51 D. In one embodiment of the present invention, the hole blocking layer is composed of only a hole blocking material having an electric dipole moment of less than 6.51 D. In one embodiment of the present invention, the hole blocking layer contains one type of hole blocking material having an electric dipole moment of less than 6.51 D. In one embodiment of the present invention, the hole blocking layer contains two or more types of hole blocking materials having an electric dipole moment of less than 6.51 D. In one embodiment of the first configuration of the invention, the hole blocking layer may comprise a hole blocking material having an electric dipole moment of 6.51 D or greater and may be composed of the same materials as described above for the electron transport layer. Examples of compounds that can be used in the hole blocking layer in the organic electroluminescent device of the first configuration are given below.

[0081] [ka]

[0082] Electron barrier layer: The electron blocking layer transports holes. In some embodiments, during hole transport, the electron blocking layer blocks electrons from reaching the hole transport layer. In some embodiments, the electron blocking layer increases the probability of recombination of electrons and holes in the light-emitting layer. In the organic electroluminescent device of the first configuration of the present invention, the electron blocking layer comprises an electron blocking material having an electric dipole moment of less than 3.08D. In one aspect of the first configuration of the present invention, the electron blocking layer is composed of only an electron blocking material having an electric dipole moment of less than 3.08D. In one aspect of the first configuration of the present invention, the electron blocking layer comprises one type of electron blocking material having an electric dipole moment of less than 3.08D. In one aspect of the first configuration of the present invention, the electron blocking layer comprises two or more types of electron blocking materials having an electric dipole moment of less than 3.08D. In one aspect of the second configuration of the present invention, the electron blocking layer may comprise an electron blocking material having an electric dipole moment of 3.08D or more, and may be composed of the same materials as described above for the hole transport layer. Preferred specific examples of compounds that can be used as the electron blocking material in the organic electroluminescent device of the second configuration are given below.

[0083] [ka]

[0084] Exciton blocking layer: The exciton blocking layer prevents excitons generated through the recombination of holes and electrons in the light-emitting layer from diffusing to the charge transport layer. In some embodiments, the exciton blocking layer allows for effective confinement of excitons in the light-emitting layer. In some embodiments, the light emission efficiency of the device is improved. In some embodiments, the exciton blocking layer is adjacent to the light-emitting layer on either the anode side or the cathode side and on both sides. In some embodiments, when the exciton blocking layer is present on the anode side, the layer may be present 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 present on the cathode side, the layer may be present between the light-emitting layer and the cathode and adjacent to the light-emitting layer. In some embodiments, a hole injection layer, an electron blocking layer, or a similar layer is present between the anode and the exciton blocking layer adjacent to the light-emitting layer on the anode side. In some embodiments, a hole injection layer, an electron blocking layer, a hole blocking layer, or a similar layer is present between the cathode and the exciton blocking layer adjacent to the 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 excited triplet energy, respectively, of the light-emitting material.

[0085] Hole transport layer: The hole transport layer comprises a hole transport material. In some embodiments, the hole transport layer is a single layer. In some embodiments, the hole transport layer has multiple layers. In some embodiments, the hole transport material has one of hole injection or transport properties and electron blocking properties. In some embodiments, the hole transport material is an organic material. In some embodiments, the hole transport material is an inorganic material. Examples of known hole transport materials that can be used in the present invention include, but are not limited to, triazole derivatives, oxadiazole derivatives, imidazole derivatives, carbazole derivatives, indolocarbazole derivatives, polyarylalkane derivatives, pyrazoline derivatives, pyrazolone derivatives, phenylenediamine derivatives, allylamine derivatives, amino-substituted chalcone derivatives, oxazole derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives, aniline copolymers, and conductive polymer oligomers (especially thiophene oligomers), or combinations thereof. In some embodiments, the hole transport material is selected from porphyrin compounds, aromatic tertiary amine compounds, and styrylamine compounds. In some embodiments, the hole transport material is an aromatic tertiary amine compound. Specific examples of preferred compounds that can be used as hole transport materials are given below.

[0086] [ka]

[0087] Electron transport layer: The electron transport layer comprises an electron transport material. In some embodiments, the electron transport layer is a single layer. In some embodiments, the electron transport layer has multiple layers. In some embodiments, the electron transport material only needs to transport electrons injected from the cathode to the light-emitting layer. In some embodiments, the electron transport material also functions as a hole-blocking material. Examples of electron transport layers that can be used in the present invention include, but are not limited to, nitro-substituted fluorene derivatives, diphenylquinone derivatives, thiopyran dioxide derivatives, carbodiimides, fluorenylidene methane derivatives, anthraquinodimethanes, anthrone derivatives, oxadiazole derivatives, azole derivatives, azine derivatives, or combinations thereof, or polymers thereof. In some embodiments, the electron transport material is a thiadiazole derivative or a quinoxaline derivative. In some embodiments, the electron transport material is a polymeric material. Specific examples of preferred compounds that can be used as electron transport materials are given below.

[0088] [ka]

[0089] In addition, examples of compounds that can be added to each organic layer are given below, which may be used as stabilizing materials, for example.

[0090] [ka]

[0091] Although the preferred materials that can be used in the organic electroluminescence element are specifically exemplified, the materials that can be used in the present invention are not limited to the following exemplified compounds. In addition, even if a compound is exemplified as a material having a specific function, it can be diverted to a material having other functions.

[0092] device: In some embodiments, the light-emitting layer is incorporated into a device, including, but not limited to, an OLED bulb, an OLED lamp, a television display, a computer monitor, a mobile phone, and a tablet. In some embodiments, the electronic device comprises an OLED having an anode, a cathode, and at least one organic layer comprising an emissive layer between the anode and the cathode. In some embodiments, the compositions described herein may be incorporated into various photosensitive or photoactivated devices, such as OLEDs or optoelectronic devices. In some embodiments, the compositions may be useful for facilitating charge or energy transfer within the device and / or as hole transport materials, such as organic light-emitting diodes (OLEDs), organic integrated circuits (OICs), organic field-effect transistors (O-FETs), organic thin film transistors (O-TFTs), organic light-emitting transistors (O-LETs), organic solar cells (O-SCs), organic optical detectors, organic photoreceptors, organic field-quench devices (O-FQDs), light-emitting fuel cells (LECs), or organic laser diodes (O-lasers).

[0093] Bulb or Lamp: In some embodiments, the electronic device comprises an OLED comprising an anode, a cathode, and at least one organic layer comprising an emissive layer between the anode and the cathode. In some embodiments, the device includes OLEDs of different colors. In some embodiments, the device includes an array including a combination of OLEDs. In some embodiments, the combination of OLEDs is a combination of three colors (e.g., RGB). In some embodiments, the combination of OLEDs is a combination of colors that are not red, green, or blue (e.g., orange and yellow-green). In some embodiments, the combination of OLEDs is a combination of two, four, or more colors. In some embodiments, the device comprises: a circuit board having a first side having a mounting surface and an opposing second side, the circuit board defining at least one opening; at least one OLED on the mounting surface, the at least one OLED having a light-emitting configuration including an anode, a cathode, and at least one organic layer including a light-emitting layer between the anode and the cathode; a housing for the circuit board; and at least one connector disposed on an end of the housing, the housing and the connector defining a package suitable for attachment to a lighting fixture. In some embodiments, the OLED light comprises a plurality of OLEDs mounted on a circuit board such that light is emitted in a plurality of directions. In some embodiments, some of the light emitted in a first direction is polarized and emitted in a second direction. In some embodiments, a reflector is used to polarize the light emitted in the first direction.

[0094] Display or Screen: In some embodiments, the light-emitting layer of the present invention can be used in a screen or display. In some embodiments, the compounds of the present invention are deposited onto a substrate using processes such as, but not limited to, vacuum evaporation, deposition, vapor deposition, or chemical vapor deposition (CVD). In some embodiments, the substrate is a photoplate structure useful in two-sided etching to provide pixels of unique aspect ratios. The screen (also called a mask) is used in the manufacturing process of an OLED display. The corresponding artwork pattern design allows for the placement of very steep narrow tie bars between pixels in the vertical direction, as well as large wide angled openings in the horizontal direction. This allows for the fine patterning of pixels required for high resolution displays while optimizing chemical vapor deposition onto the TFT backplane. The internal patterning of the pixel allows for the construction of three-dimensional pixel openings of various aspect ratios in the horizontal and vertical directions. Additionally, the use of imaged "stripes" or halftone circles in the pixel area protects etching in certain areas until those particular patterns are undercut and removed from the substrate. At that point, all pixel areas are treated with similar etch rates, but the depth varies with the halftone pattern. Varying the size and spacing of the halftone patterns allows etching with different protection rates within the pixel, allowing for the localized deep etching required to create steep vertical bevels. The preferred material for the deposition mask is Invar. Invar is a metal alloy that is cold rolled into long thin sheets at steel mills. Invar cannot be electrodeposited onto the spin mandrel as a nickel mask. A suitable and low-cost method for forming open areas in the deposition mask is by wet chemical etching. In some embodiments, the screen or display pattern is a pixel matrix on a substrate. In some embodiments, the screen or display pattern is fabricated using lithography (e.g., photolithography and e-beam lithography). In some embodiments, the screen or display pattern is fabricated using wet chemical etching. In further embodiments, the screen or display pattern is fabricated using plasma etching.

[0095] How the device is manufactured: OLED displays are generally manufactured by forming a large mother panel and then cutting the mother panel into cell panels. Usually, each cell panel on the mother panel is formed by forming a thin film transistor (TFT) having an active layer and source / drain electrodes on a base substrate, applying a planarizing film to the TFT, sequentially forming a pixel electrode, a light-emitting layer, a counter electrode and an encapsulation layer, and then cutting the cell panel from the mother panel. OLED displays are generally manufactured by forming a large mother panel and then cutting the mother panel into cell panels. Usually, each cell panel on the mother panel is formed by forming a thin film transistor (TFT) having an active layer and source / drain electrodes on a base substrate, applying a planarizing film to the TFT, sequentially forming a pixel electrode, a light-emitting layer, a counter electrode and an encapsulation layer, and then cutting the cell panel from the mother panel.

[0096] In another aspect of the invention, there is provided a method for manufacturing an organic light emitting diode (OLED) display, the method comprising: forming a barrier layer on a base substrate of a mother panel; forming a plurality of display units on the barrier layer in the form of a cell panel; forming an encapsulation layer over each of the display units of the cell panel; and applying an organic film to the interface between the cell panels. In some embodiments, the barrier layer is an inorganic film, for example made of SiNx, and the ends of the barrier layer are covered with an organic film made of polyimide or acrylic. In some embodiments, the organic film helps the mother panel to be cut softly into cell panels. In some embodiments, the thin film transistor (TFT) layer includes a light-emitting layer, a gate electrode, and source / drain electrodes. Each of the plurality of display units may include a thin film transistor (TFT) layer, a planarization film formed on the TFT layer, and a light-emitting unit formed on the planarization film, and the organic film applied to the interface is formed of the same material as the planarization film and is formed at the same time as the planarization film. In some embodiments, the light-emitting unit is connected to the TFT layer by a passivation layer, the planarization film therebetween, and an encapsulation layer that covers and protects the light-emitting unit. In some embodiments of the manufacturing method, the organic film is not connected to the display unit or the encapsulation layer.

[0097] Each of the organic film and the planarization film may include one of polyimide and acrylic. In some embodiments, the barrier layer may be an inorganic film. In some embodiments, the base substrate may be formed of polyimide. The method may further include attaching a carrier substrate formed of a glass material to one surface of the base substrate formed of polyimide prior to forming a barrier layer on the other surface of the base substrate, and separating the carrier substrate from the base substrate prior to cutting along the interface. In some embodiments, the OLED display is a flexible display. In some embodiments, the passivation layer is an organic film disposed on the TFT layer for covering the TFT layer. In some embodiments, the planarization film is an organic film formed on the passivation layer. In some embodiments, the planarization film is formed of polyimide or acrylic, as is the organic film formed on the edge of the barrier layer. In some embodiments, the planarization film and the organic film are formed simultaneously during the manufacture of an OLED display. In some embodiments, the organic film may be formed on the edge of the barrier layer, such that a portion of the organic film directly contacts the base substrate, and the remaining portion of the organic film contacts the barrier layer while surrounding the edge of the barrier layer.

[0098] In some embodiments, the light-emitting layer comprises a pixel electrode, a counter electrode, and an organic light-emitting layer disposed between the pixel electrode and the counter electrode, hi some embodiments, the pixel electrode is coupled to a source / drain electrode of a TFT layer. In some embodiments, when a voltage is applied to the pixel electrode through the TFT layer, a suitable voltage is formed between the pixel electrode and the counter electrode, which causes the organic light-emitting layer to emit light, thereby forming an image. Hereinafter, an image-forming unit having a TFT layer and a light-emitting unit is referred to as a display unit. In some embodiments, the encapsulation layer that covers the display units and prevents the penetration of external moisture may be formed into a thin-film encapsulation structure in which organic films and inorganic films are alternately laminated. In some embodiments, the encapsulation layer has a thin-film encapsulation structure in which a plurality of thin films are laminated. In some embodiments, the organic film applied to the interface portion is disposed at an interval with each of the plurality of display units. In some embodiments, the organic film is formed in such a manner that a portion of the organic film directly contacts the base substrate, and the remaining portion of the organic film contacts the barrier layer while surrounding the end of the barrier layer.

[0099] In one embodiment, the OLED display is flexible and uses a flexible base substrate formed of polyimide, hi some embodiments, the base substrate is formed on a carrier substrate formed of a glass material, and the carrier substrate is then separated. In some embodiments, a barrier layer is formed on a surface of the base substrate opposite the carrier substrate. In one embodiment, the barrier layer is patterned according to the size of each cell panel. For example, the base substrate is formed on all surfaces of the mother panel, while the barrier layer is formed according to the size of each cell panel, thereby forming grooves at the interfaces between the barrier layers of the cell panels. Each cell panel can be cut along the grooves.

[0100] In some embodiments, the method further includes a step of cutting along the interface, where a groove is formed in the barrier layer and at least a portion of the organic film is formed in the groove, and the groove does not penetrate the base substrate. In some embodiments, the TFT layer of each cell panel is formed, and a passivation layer, which is an inorganic film, and a planarization film, which is an organic film, are disposed on the TFT layer to cover the TFT layer. At the same time as the planarization film, which is made of, for example, polyimide or acrylic, is formed, the groove of the interface is covered with an organic film, which is made of, for example, polyimide or acrylic. This prevents cracks from occurring when each cell panel is cut along the groove at the interface by having the organic film absorb the impact that occurs. That is, if all the barrier layers are completely exposed without the organic film, when each cell panel is cut along the groove at the interface, the impact that occurs will be transmitted to the barrier layer, thereby increasing the risk of cracks. However, in one embodiment, the groove of the interface between the barrier layers is covered with an organic film to absorb the impact that would otherwise be transmitted to the barrier layer, so that each cell panel can be cut softly and prevent cracks from occurring in the barrier layer. In one embodiment, the organic film and the planarization film covering the groove of the interface are spaced apart from each other. For example, when the organic film and the planarization film are connected to each other as one layer, external moisture may penetrate into the display unit through the planarization film and the remaining part of the organic film, so 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.

[0101] In some embodiments, the display unit is formed by forming a light-emitting unit, and the encapsulation layer is disposed on the display unit to cover the display unit. Thus, after the mother panel is completely manufactured, the carrier substrate carrying the base substrate is separated from the base substrate. In some embodiments, when a laser beam is irradiated onto the carrier substrate, the carrier substrate is separated from the base substrate due to the difference in thermal expansion coefficient between the carrier substrate and the base substrate. In some embodiments, the mother panel is cut into individual cell panels. In some embodiments, the mother panel is cut along the interface between the cell panels using a cutter. In some embodiments, the grooves at the interface along which the mother panel is cut are covered with an organic film, which absorbs shock during cutting. In some embodiments, the barrier layer is prevented from cracking during cutting. In some embodiments, the methods reduce product defect rates and stabilize product quality. Another embodiment is an OLED display having a barrier layer formed on a base substrate, a display unit formed on the barrier layer, an encapsulation layer formed on the display unit, and an organic film applied to the edges of the barrier layer.

[0102] <Design method of organic electroluminescence element> Next, a first design method and a second design method for the organic electroluminescence element of the present invention will be described. A first design method for an organic electroluminescent device of the present invention is a design method for an organic electroluminescent device having an anode, a cathode, and an organic layer between the anode and cathode, the organic layer including, in order from the anode side, an electron blocking layer, an emitting layer, and a hole blocking layer, in this order, wherein the electron blocking layer is designed to include an electron blocking material having an electric dipole moment of less than 3.08 D, and the hole blocking layer is designed to include a hole blocking material having an electric dipole moment of less than 6.51 D. According to the first design method of the present invention, it is possible to design an organic electroluminescence element that exhibits little change in luminous intensity over time and has a long element life. For the description, preferred range, and specific examples of the electron blocking material having an electric dipole moment of less than 3.08 D, please refer to the description in the above (Electron blocking material). For the description, preferred range, and specific examples of the hole blocking material having an electric dipole moment of less than 6.51 D, please refer to the description in the above (Hole blocking material). In addition, for the numerical values ​​of the electric dipole moments of specific electron blocking materials and hole blocking materials, please refer to the Examples column. For the configuration of the organic electroluminescence element, please refer to the description in the above [Overall configuration of organic electroluminescence element] column.

[0103] One embodiment of the first design method of the present invention includes the steps of searching a database storing the electric dipole moments of a plurality of materials as data for a material having an electric dipole moment of less than 3.08 D, and selecting an electron blocking material to be used in an organic light-emitting element from the group of materials found in the search, searching the database for a material having an electric dipole moment of less than 6.51 D, and selecting a hole blocking material to be used in an organic light-emitting element from the group of materials found in the search, and designing an organic electroluminescence element using the selected electron blocking material and hole blocking material.

[0104] The second design method for an organic electroluminescent device of the present invention is a design method for an organic electroluminescent device having an anode, a cathode, and an organic layer between the anode and cathode, which includes, in order from the anode side, an electron blocking layer containing an electron blocking material, an emitting layer, and a hole blocking layer containing a hole blocking material, in which the sum of the electric dipole moment of the electron blocking material and the electric dipole moment of the hole blocking material is designed to be less than 3.00 D. According to the second design method of the present invention, it is possible to more reliably design an organic electroluminescence element having a long element life and small change in luminous intensity over time. For the description, preferred range, and specific examples of the electron blocking material having an electric dipole moment of less than 3.08 D, please refer to the description in the above (Electron blocking material). For the description, preferred range, and specific examples of the hole blocking material having an electric dipole moment of less than 6.51 D, please refer to the description in the above (Hole blocking material). For the numerical values ​​of the electric dipole moments of specific electron blocking materials and hole blocking materials, please refer to the Examples column. For specific examples of combinations of materials that result in a sum of electric dipole moments of less than 3.00 D, please refer to the combinations described in the above <Organic electroluminescent element> column. For the configuration of the organic electroluminescent element, please refer to the description in the above [Overall configuration of organic electroluminescent element] column.

[0105] One embodiment of the second design method of the present invention includes the steps of searching a database storing the electric dipole moments of a plurality of materials as data for two materials whose sum of electric dipole moments is less than 3.00 D, and selecting an electron blocking material and a hole blocking material to be used in an organic light-emitting element from a group of combinations of materials found in the search, and designing an organic electroluminescence element using the electron blocking material and the hole blocking material selected in the step.

[0106] In a preferred embodiment of the second design method of the present invention, the electron blocking layer comprises an electron blocking material having an electric dipole moment of less than 2.20 D, the hole blocking layer comprises a hole blocking material having an electric dipole moment of less than 2.00 D, and the sum of the electric dipole moment of the electron blocking material and the electric dipole moment of the hole blocking material are designed to be less than 3.00 D. In a preferred embodiment of the second design method of the present invention, the method includes the steps of: searching for an electron barrier material having an electric dipole moment of less than 2.20 D from a database storing the electric dipole moments of a plurality of types of electron barrier materials as data; searching for a hole barrier material having an electric dipole moment of less than 2.00 D from a database storing the electric dipole moments of a plurality of types of hole barrier materials as data; searching for a combination of an electron barrier material and a hole barrier material having a sum of electric dipole moments of less than 3.00 D from the electron barrier materials and hole barrier materials found in the search; selecting an electron barrier material and a hole barrier material to be used in an organic light-emitting element from the group of combinations of materials found in the search; and designing an organic electroluminescence element using the electron barrier material and the hole blocking material selected in the step. According to this embodiment, it is possible to more reliably design an organic electroluminescence element with a long element life and with a small change in luminous intensity over time.

[0107] <Program> The program of the present invention is a program for carrying out at least one of the first and second design methods for an organic electroluminescence element of the present invention. For the steps constituting the program, the description in the above section <Design method of organic electroluminescence element> can be referred to. The program of the present invention may be a program for implementing either the first design method or the second design method of the organic electroluminescent element of the present invention, or may be a program for implementing both the first design method and the second design method. The program of the present invention can be stored in a computer-readable recording medium. Furthermore, according to the present invention, it is possible to provide a readable recording medium storing the program of the present invention. EXAMPLES

[0108] The features of the present invention will be described in more detail below with reference to examples. The materials, processing contents, processing procedures, etc. shown below can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be interpreted as being limited by the specific examples shown below. The evaluation of the light emission performance was performed using a source meter (Keithley: 2400 series), a semiconductor parameter analyzer (Agilent Technologies: E5273A), an optical power meter measuring device (Newport: 1930C), an optical spectrometer (Ocean Optics: USB2000), a spectroradiometer (Topcon: SR-3), and a streak camera (Hamamatsu Photonics C4334).

[0109] Example 1 Each thin film was deposited on a glass substrate with an anode made of indium tin oxide (ITO) with a thickness of 50 nm by vacuum deposition at a vacuum degree of 5.0 × 10 -4 The layers were laminated at 1000 Pa. First, HATCN was evaporated on ITO to a thickness of 10 nm to form a hole injection layer. Next, NPD was evaporated to a thickness of 30 nm to form a second hole transport layer, and TrisPCz was evaporated on top of that to a thickness of 10 nm to form a first hole transport layer. Next, compound EB1 was evaporated to a thickness of 5 nm to form an electron blocking layer. Next, compound H1 and compound T1 were co-evaporated from different evaporation sources to form a layer with a thickness of 40 nm to serve as an emitting layer. At this time, the concentrations of compound H1 and compound T1 were 65% by weight and 35% by weight, respectively. Next, HB was evaporated to a thickness of 10 nm to form a hole blocking layer, and HB and Liq were co-evaporated from different evaporation sources to form an electron transport layer with a thickness of 30 nm on top of that. At this time, the concentrations of HB and Liq were 70% by weight and 30% by weight, respectively. Furthermore, Liq was evaporated to a thickness of 2 nm to form an electron injection layer, and aluminum (Al) was evaporated thereon to a thickness of 100 nm to form a cathode, thereby completing an organic electroluminescence element (EL element).

[0110] (Examples 2 to 4, Comparative Example 1) Organic electroluminescence devices (EL devices) were produced in the same manner as in Example 1, except that the compounds shown in Table 1 were used as the electron blocking material instead of compound EB1.

[0111] The organic electroluminescence devices prepared in Examples 1 to 4 and Comparative Example 1 were subjected to a luminescence current of 25.2 mA / cm 2 The device was driven at 100 Hz, and the voltage, external quantum efficiency (EQE), and lifetime (LT95) were measured, along with the absolute values ​​of the HOMO energy, LUMO energy, and electric dipole moment of the compounds used in the electron blocking layer. Table 1 shows the results, and FIG. 1 shows a graph plotting the electric dipole moment on the horizontal axis and LT95 on the vertical axis. Here, LT95 is the time it takes for the emission intensity to reach 95% of that at the start of driving. In Table 1, the voltage, EQE, and LT95 are expressed as percentages relative to the values ​​measured in Comparative Example 1. "EB1" and the like in FIG. 1 are the compound numbers of the electron blocking materials used in each example.

[0112] [Table 1]

[0113] As shown in Fig. 1, the EL elements of Examples 1 to 4, in which the electric dipole moment of the electron-blocking material is less than 3.08D, exhibited a longer element life than the EL element of Comparative Example 1, in which the electric dipole moment of the electron-blocking material is more than 3.08D. In particular, the EL elements of Examples 1 and 2, in which the electric dipole moment of the electron-blocking material is less than 1.25D, exhibited an element life more than twice that of the EL element of Comparative Example 1. From this, it was confirmed that the life of the EL element can be significantly improved by setting the electric dipole moment of the electron-blocking material to less than 3.08D, preferably less than 1.25D. In addition, since there was no significant difference in the emission characteristics among the EL devices of Examples 1 to 4, which had different HOMO energies of the electron blocking materials, it was considered that the influence of the carrier balance and carrier mobility on the HOMO energy was small, and it was suggested that reducing the electric dipole moment of the electron blocking material greatly contributed to improving the device life.

[0114] (Examples 5 to 8, Comparative Example 2) An organic electroluminescence device (EL device) was produced in the same manner as in Example 1, except that PTCz was used as the electron blocking material instead of compound EB1, and a compound shown in Table 2 was used as the hole blocking material instead of HB.

[0115] For the organic electroluminescence devices fabricated in Examples 5 to 8 and Comparative Example 2, the voltage, external quantum efficiency (EQE), and lifetime (LT95) were measured, and the absolute values ​​of the HOMO energy, the absolute values ​​of the LUMO energy, and the electric dipole moment of the compounds used in the hole blocking layer are shown in Table 2, and a graph plotting the electric dipole moment on the horizontal axis and LT95 on the vertical axis is shown in FIG. 2. In Table 2, the voltage, EQE, and LT95 are expressed as percentages relative to the values ​​measured in Comparative Example 2. "HB1" and the like in FIG. 2 are the compound numbers of the hole blocking materials used in each Example.

[0116] [Table 2]

[0117] As shown in Fig. 2, the EL elements of Examples 5 to 8, in which the electric dipole moment of the hole-blocking material is less than 6.51 D, exhibited a longer element life than the EL element of Comparative Example 2, in which the electric dipole moment of the hole-blocking material exceeds 6.51 D. In particular, the EL elements of Examples 7 and 8, in which the electric dipole moment is less than 0.50 D, exhibited an element life 1.7 times or more longer than that of the EL element of Comparative Example 2. From this, it was confirmed that the life of the EL element can be improved by specifying the electric dipole moment of the hole-blocking material to be less than 6.51 D, preferably less than 2.00 D or less than 1.00 D, and particularly preferably less than 0.50 D. In addition, since there was no significant difference in the emission characteristics among the EL devices of Examples 5 to 8, which had different LUMO energies of hole-blocking materials, it was suggested that the influence of carrier balance and carrier mobility on the LUMO energy was small, and that reducing the electric dipole moment of the hole-blocking material greatly contributed to improving the device life.

[0118] (Examples 9 and 10) An organic electroluminescence device (EL device) was produced in the same manner as in Example 1, except that compound T2 was used as the light-emitting material instead of compound T1, a compound shown in Table 3 was used as the electron blocking material instead of compound EB1, and a compound shown in Table 3 was used as the hole blocking material instead of HB.

[0119] The organic electroluminescence devices prepared in Examples 9 and 10 were measured for voltage, external quantum efficiency (EQE), and lifetime (LT95), and the absolute values ​​of the HOMO energy, absolute values ​​of the LUMO energy, and electric dipole moment of each compound used in the electron blocking layer and hole blocking layer are shown in Table 3. The luminescence decay curves of each device are shown in Figure 3. In Table 3, the voltage, EQE, and LT95 are expressed as percentages relative to the values ​​measured in Example 9.

[0120] [Table 3]

[0121] As shown in Fig. 3, the EL element of Example 10, in which the sum of the electric dipole moment of the electron blocking material and the electric dipole moment of the hole blocking material is less than 3.00 D, showed less change in luminescence intensity over time than the EL element of Example 9 (comparison standard in the invention for the sum of electric dipole moments) in which the sum of the electric dipole moments exceeds 3.00 D. This confirmed that the change in luminescence intensity over time can be further suppressed by setting the sum of the electric dipole moment of the electron blocking material and the electric dipole moment of the hole blocking material to less than 3.00 D.

[0122] [ka] JPEG2024171218000038.jpg239163JPEG2024171218000039.jpg113164 [Industrial Applicability]

[0123] In the present invention, the electric dipole moment of the electron blocking material and the hole blocking material is specified, thereby improving the element life of the organic electroluminescence element. Therefore, according to the present invention, it is possible to provide an organic electroluminescence element with excellent practicality. Therefore, the present invention has a high industrial applicability.

Claims

1. An organic electroluminescent element having an anode, a cathode, and at least one organic layer including a light-emitting layer between the anode and the cathode, Between the anode and the light-emitting layer, there is an electron barrier layer comprising an electron barrier material represented by the following general formula (9) or the following general formula (10) and having an electric dipole moment of less than 3.08 D. An organic electroluminescent element having a hole barrier layer between the cathode and the light-emitting layer, the hole barrier material being compound HB2, compound HB3, or compound HB4 as described below. 【Chemistry 1】 [In general formulas (9) and (10), R11 to R18 and R21 to R30 each independently represent a hydrogen atom, a deuterium atom, or a substituted or unsubstituted aryl group, and R81, R82, and R84 to R88 each independently represent a hydrogen atom or a deuterium atom. n101 is 0. X2 represents an oxygen atom or a sulfur atom, and X8 represents an oxygen atom.] 【Chemistry 2】

2. The organic electroluminescent element according to claim 1, wherein the sum of the electric dipole moment of the electron barrier material and the electric dipole moment of the hole barrier material is less than 3.00 D.

3. The organic electroluminescent element according to claim 1, wherein the sum of the electric dipole moment of the electron barrier material and the electric dipole moment of the hole barrier material is less than 2.00 D.

4. The organic electroluminescent element according to claim 1, wherein the electron barrier material has a structure represented by the general formula (10).

5. The organic electroluminescent element according to claim 1, wherein the electron barrier material has a structure represented by the general formula (9).

6. The organic electroluminescent element according to claim 1, wherein the phenylene group that links the benzene ring to which R 81, R 82, and R 84 are bonded and the nitrogen atom in general formula (9) and general formula (10) is an unsubstituted m-phenylene group.

7. The organic electroluminescent element according to claim 1, wherein the phenylene group that links the benzene ring to which R 81, R 82, and R 84 are bonded and the nitrogen atom in general formula (9) and general formula (10) is an unsubstituted p-phenylene group.

8. The organic electroluminescent element according to claim 1, wherein at least one of R11 to R18, R81, R82 and R84 to R88 of the general formula (9) is a substituted or unsubstituted aryl group.

9. The organic electroluminescent element according to claim 1, wherein at least one of R21 to R30, R81, R82 and R84 to R88 of the general formula (10) is a substituted or unsubstituted aryl group.

10. The organic electroluminescent element according to any one of claims 1 to 9, wherein the light-emitting layer includes a delayed fluorescence material.

11. A method for designing an organic electroluminescent element having an anode, a cathode, and an organic layer between the anode and the cathode, the organic layer comprising, in order from the anode side, an electron barrier layer, an emissive layer, and a hole barrier layer, The electron barrier layer comprises an electron barrier material represented by the following general formula (9) or the following general formula (10) and having an electric dipole moment of less than 3.08 D. A method for designing an organic electroluminescent device, wherein the hole barrier layer is designed to include a hole barrier material which is compound HB2, compound HB3, or compound HB4. 【Transformation 3】 [In general formulas (9) and (10), R11 to R18 and R21 to R30 each independently represent a hydrogen atom, a deuterium atom, or a substituted or unsubstituted aryl group, and R81, R82, and R84 to R88 each independently represent a hydrogen atom or a deuterium atom. n101 is 0. X2 represents an oxygen atom or a sulfur atom, and X8 represents an oxygen atom.] 【Chemistry 4】

12. The process involves searching a database containing data on the electric dipole moments of multiple types of materials for materials that are represented by the general formula (9) or the general formula (10) and have an electric dipole moment of less than 3.08 D, and selecting an electron barrier material to be used in an organic light-emitting device from the group of materials found in the search. A step of selecting a hole barrier material to be used in an organic light-emitting device from among the compounds HB2, HB3, and HB4, The design method according to claim 11, further comprising the step of designing an organic electroluminescent element using the electron barrier material and hole barrier material selected in the above step.

13. The design method according to claim 11, wherein the electron barrier material and the hole barrier material are selected such that the sum of the electric dipole moments of the electron barrier material and the electric dipole moments of the hole barrier material is less than 3.00D.

14. A program for carrying out the method described in any one of claims 11 to 13.

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