Triazine compounds, materials for organic electroluminescent devices, electron transport materials for organic electroluminescent devices, and organic electroluminescent devices.

Abstract

The purpose of the present invention is to provide a triazine compound that contributes in manufacturing of an organic electroluminescent element having excellent durability and drive voltage.　This triazine compound is represented by formula (1). In formula (1), A and B each represent an aryl group having 6-20 carbon atoms. L represents a phenyl group or a naphthyl group. n represents 0 or 1. C represents a group which is X, Y, or Z. Ar1 and Ar2 each represent an aromatic hydrocarbon group or a pyridyl group.

Description

Technical Field

[0001] The present invention relates to a triazine compound, a material for an organic electroluminescent device, an electron transport material for an organic electroluminescent device, and an organic electroluminescent device.

Background Art

[0002] Organic electroluminescent devices are used not only for small displays but also for applications such as large TVs and lighting, and their development is being actively carried out.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0004] In recent years, the market requirements for organic electroluminescent devices have been increasing, and materials excellent in any of current efficiency characteristics, driving voltage characteristics, and long-life characteristics are demanded. Here, Patent Document 1 discloses a triazine compound in which the 2, 4, and 6 positions are substituted with different substituents, Patent Document 2 discloses a triazine compound having a 1,2-phenylene moiety, and Patent Document 3 discloses an azine compound in which the 2 position is substituted with a phenyl group.

[0005] However, organic electroluminescent devices using the compounds disclosed in Patent Documents 1 to 3 in the electron transport layer have insufficient characteristics of driving voltage and driving life, and further improvement is required.

[0006] One aspect of the present invention aims to provide a triazine compound, a material for an organic electroluminescent device, and an electron transport material for an organic electroluminescent device, which contribute to the production of an organic electroluminescent device having a low driving voltage and excellent durability.

[0007] Another aspect of the present invention aims to provide an organic electroluminescent device having a low driving voltage and excellent durability.

Means for Solving the Problems

[0008] According to one aspect of the present invention, a triazine compound represented by formula (1) is provided: The triazine compound represented by formula (1).

[0009]

Chemical Formula

[0010] In formula (1), A and B each represent an aryl group having 6 to 20 carbon atoms. L represents a phenyl group or a naphthyl group. n is 0 or 1. C represents any one of the following groups X, Y, and Z.

[0011]

Chemical Formula

[0012] , , 1 , 1 ,

[0013] , Ar 2 represents an aromatic hydrocarbon group or a pyridyl group.

[0012] According to one aspect of the present invention, the triazine compound represented by formula (1) includes triazine compounds represented by the following formula X(1), formula Y(1), and formula Z(1). A, B, L, n, Ar 1 , Ar 2 are respectively defined by the triazine compounds represented by formula X(1), formula Y(1), and formula Z(1).

[0013] According to one aspect of the present invention, a triazine compound represented by formula X(1) is provided:

[0014] [ka]

[0015] In the case of equation X(1), A represents one of the bases selected from equations X(A-1) to X(A-9):

[0016] [ka]

[0017] B represents one of the bases selected from equations X(B-1) to X(B-15):

[0018] [ka]

[0019] Ar 1 teeth, An aryl group having 6 to 30 carbon atoms may be substituted with one or more groups selected from the group consisting of C1-C12 alkyl groups, C3-C20 cycloalkyl groups, cyano groups, diarylboryl groups, and phosphine oxide groups, or Represents a pyridyl group which may be substituted with a methyl group or a phenyl group. Ar 2 teeth, An aryl group having 6 to 30 carbon atoms may be substituted with one or more groups selected from the group consisting of C1-C12 alkyl groups, C3-C20 cycloalkyl groups, cyano groups, diarylboryl groups, and phosphine oxide groups, or This represents a pyridyl group, which may be substituted with a methyl group or a phenyl group.

[0020] According to another aspect of the present invention, a triazine compound represented by formula Y(1) is provided:

[0021] [ka]

[0022] In the case of equation Y(1), A represents an aryl group with 6 to 20 carbon atoms; B is An aryl group having 6 to 20 carbon atoms may be substituted with one or more groups selected from the group consisting of C1-C12 alkyl groups, C3-C20 cycloalkyl groups, cyano groups, diarylboryl groups, and phosphine oxide groups, or Represents a heteroaryl group with 4 to 30 carbon atoms containing an oxygen or sulfur atom; Ar 1 ~Ar 2 Each of them operates independently. An aryl group having 6 to 26 carbon atoms may be substituted with one or more groups selected from the group consisting of C1-C12 alkyl groups, C3-C20 cycloalkyl groups, cyano groups, diarylboryl groups, and phosphine oxide groups, or Represents a pyridinyl group, which may be substituted with a methyl group or a phenyl group; n represents an integer between 0 and 1; L represents one of the bases selected from equations Y(2-1) to Y(2-5).

[0023] [ka]

[0024] According to another aspect of the present invention, a triazine compound represented by formula Z(1) is provided:

[0025] [ka]

[0026] In the case of equation Z(1), A represents a phenyl group, a biphenylyl group, or a naphthyl group, which may be substituted by one or more substituents selected from the group consisting of a fluorine atom, a methyl group, and a cyano group; B represents a phenyl group, a biphenylyl group, or a naphthyl group, which may be substituted by one or more substituents selected from the group consisting of a fluorine atom, a methyl group, and a cyano group; Ar 1 represents a phenyl group or a naphthyl group, which may be substituted by one or more substituents selected from the group consisting of a fluorine atom, a methyl group, and a cyano group; Ar 2 represents a phenyl group or a naphthyl group, which may be substituted by one or more substituents selected from the group consisting of a fluorine atom, a methyl group, and a cyano group.

[0027] According to another aspect of the present invention, a material for an organic electroluminescent device containing the above triazine compound is provided. According to another aspect of the present invention, an electron transport material for an organic electroluminescent device containing the above triazine compound is provided. According to another aspect of the present invention, an organic electroluminescent device containing the above triazine compound is provided.

Advantages of the Invention

[0028] According to one aspect of the present invention, it is possible to provide a triazine compound, a material for an organic electroluminescent device, and an electron transport material for an organic electroluminescent device, which contribute to the production of an organic electroluminescent device having a low driving voltage and excellent durability. According to another aspect of the present invention, it is possible to provide an organic electroluminescent device having a low driving voltage and excellent durability.

Brief Description of the Drawings

[0029] [Figure 1] It is a schematic cross-sectional view showing an example of the laminated structure of an organic electroluminescent device containing a triazine compound according to one aspect of the present invention. [Figure 2]This is a schematic cross-sectional view showing an example of a stacked configuration of an organic electroluminescent element containing a triazine compound according to one aspect of the present invention (e.g., Element Example 1). [Modes for carrying out the invention]

[0030] The following describes in detail a triazine compound according to one aspect of the present invention.

[0031] <Triadine compounds> According to one aspect of the present invention, a triazine compound represented by formula (1) is provided: A triazine compound represented by formula (1).

[0032] [ka] In formula (1), A and B represent aryl groups with 6 to 20 carbon atoms. L represents a phenyl group or a naphthyl group. n is either 0 or 1. C represents one of the following bases: X, Y, or Z.

[0033] [ka] Ar 1 Ar 2 This represents an aromatic hydrocarbon group or a pyridyl group.

[0034] The triazine compound represented by formula (1) is a triazine compound that includes embodiments represented by the following formulas X(1), Y(1), and Z(1). The embodiments represented by formulas X(1), Y(1), and Z(1) will be described below.

[0035] <Triadine compound X(1)> A triazine compound according to one aspect of the present invention is represented by formula X(1):

[0036] [ka]

[0037] In the case of equation X(1), A represents one of the bases selected from equations X(A-1) to X(A-9):

[0038] [ka]

[0039] B represents one of the bases selected from equations X(B-1) to X(B-15):

[0040] [ka]

[0041] Ar 1 teeth, An aryl group having 6 to 30 carbon atoms may be substituted with one or more groups selected from the group consisting of C1-C12 alkyl groups, C3-C20 cycloalkyl groups, cyano groups, diarylboryl groups, and phosphine oxide groups, or Represents a pyridyl group which may be substituted with a methyl group or a phenyl group. Ar 2 teeth, An aryl group having 6 to 30 carbon atoms may be substituted with one or more groups selected from the group consisting of C1-C12 alkyl groups, C3-C20 cycloalkyl groups, cyano groups, diarylboryl groups, and phosphine oxide groups, or This represents a pyridyl group, which may be substituted with a methyl group or a phenyl group.

[0042] [A,B,Ar 1 ,Ar 2 [Regarding preferred combinations] In the triazine compound represented by formula X(1), preferred A, B, Ar 1 ,Ar 2 The combinations of the first to eighth embodiments are as follows:

[0043] • First aspect A represents one of the bases selected from equations X(A-1) to X(A-9), Ar 1 However, it represents an aryl group having 6 to 30 carbon atoms, which may be substituted with one or more groups selected from the group consisting of alkyl groups having 1 to 12 carbon atoms, cycloalkyl groups having 3 to 20 carbon atoms, cyano groups, diarylboryl groups, and phosphine oxide groups. Ar 2 However, it represents an aryl group having 6 to 30 carbon atoms that may be substituted with one or more groups selected from the group consisting of alkyl groups having 1 to 12 carbon atoms, cycloalkyl groups having 3 to 20 carbon atoms, cyano groups, diarylboryl groups, and phosphine oxide groups.

[0044] • Second aspect B represents one of the bases selected from the formulas X(B-1)~X(B-4), (B-7)~X(B-8), and (B-10)~X(B-11).

[0045] • Third aspect A represents one of the bases selected from equations X(A-1) to X(A-9), Ar 1 However, it represents an aryl group having 6 to 30 carbon atoms, which may be substituted with one or more groups selected from the group consisting of alkyl groups having 1 to 12 carbon atoms, cycloalkyl groups having 3 to 20 carbon atoms, cyano groups, diarylboryl groups, and phosphine oxide groups. Ar 2 However, it represents an aryl group having 6 to 30 carbon atoms that may be substituted with one or more groups selected from the group consisting of alkyl groups having 1 to 12 carbon atoms, cycloalkyl groups having 3 to 20 carbon atoms, cyano groups, diarylboryl groups, and phosphine oxide groups.

[0046] • Fourth aspect A represents one of the bases selected from equations X(A-1) to X(A-4), B represents a base selected from equations X(B-1)~X(B-4), X(B-7)~X(B-8), and X(B-10)~X(B-11), Ar 1 However, it represents an aryl group having 6 to 30 carbon atoms, which may be substituted with one or more groups selected from the group consisting of alkyl groups having 1 to 12 carbon atoms, cycloalkyl groups having 3 to 20 carbon atoms, cyano groups, diarylboryl groups, and phosphine oxide groups. Ar 2 However, it represents an aryl group having 6 to 30 carbon atoms that may be substituted with one or more groups selected from the group consisting of alkyl groups having 1 to 12 carbon atoms, cycloalkyl groups having 3 to 20 carbon atoms, cyano groups, diarylboryl groups, and phosphine oxide groups.

[0047] • Fifth aspect Ar 1 However, it represents a phenyl group, 1-naphthalenyl group, 2-naphthalenyl group, 2-biphenylyl group, 3-biphenylyl group, 4-biphenylyl group, 2-(1-naphthalenyl)phenyl group, 3-(1-naphthalenyl)phenyl group, 4-(1-naphthalenyl)phenyl group, 2-(2-naphthalenyl)phenyl group, 3-(2-naphthalenyl)phenyl group, 4-(2-naphthalenyl)phenyl group, 4-(2-naphthalenyl)phenyl group, 4-phenylnaphthalen-1-yl group, 5-phenylnaphthalen-1-yl group, 6-phenylnaphthalen-2-yl group, 7-phenylnaphthalen-2-yl group, which may be substituted with one or more groups selected from the group consisting of alkyl groups having 1 to 12 carbon atoms, cycloalkyl groups having 3 to 20 carbon atoms, cyano group, diarylboryl group, and phosphine oxide group. Ar 2This represents a phenyl group, 1-naphthalenyl group, 2-naphthalenyl group, 2-biphenylyl group, 3-biphenylyl group, 4-biphenylyl group, 2-(1-naphthalenyl)phenyl group, 3-(1-naphthalenyl)phenyl group, 4-(1-naphthalenyl)phenyl group, 2-(2-naphthalenyl)phenyl group, 3-(2-naphthalenyl)phenyl group, 4-(2-naphthalenyl)phenyl group, 4-(2-naphthalenyl)phenyl group, 4-phenylnaphthalen-1-yl group, 5-phenylnaphthalen-1-yl group, 6-phenylnaphthalen-2-yl group, or 7-phenylnaphthalen-2-yl group, which may be substituted with one or more groups selected from the group consisting of alkyl groups having 1 to 12 carbon atoms, cycloalkyl groups having 3 to 20 carbon atoms, cyano groups, diarylboryl groups, and phosphine oxide groups.

[0048] • Sixth aspect Ar 1 However, it represents a phenyl group, 1-naphthalenyl group, 2-naphthalenyl group, 2-biphenylyl group, 3-biphenylyl group, or 4-biphenylyl group, which may be substituted with one or more groups selected from the group consisting of C1-C12 alkyl groups, C3-C20 cycloalkyl groups, cyano groups, diarylboryl groups, and phosphine oxide groups. Ar 2 This represents a phenyl group, 1-naphthalenyl group, 2-naphthalenyl group, 2-biphenylyl group, 3-biphenylyl group, or 4-biphenylyl group, which may be substituted with one or more groups selected from the group consisting of C1-C12 alkyl groups, C3-C20 cycloalkyl groups, cyano groups, diarylboryl groups, and phosphine oxide groups.

[0049] • Seventh aspect A represents one of the bases selected from equations X(A-1) to X(A-4), B represents one of the bases selected from equations X(B-1) to X(B-4), Ar 1 However, this represents a phenyl group, a 1-naphthalenyl group, a 2-naphthalenyl group, a 2-biphenylyl group, a 3-biphenylyl group, and a 4-biphenylyl group. Ar 2These represent a phenyl group, a 1-naphthalenyl group, a 2-naphthalenyl group, a 2-biphenylyl group, a 3-biphenylyl group, and a 4-biphenylyl group.

[0050] • Eighth aspect A is a group represented by the formula X(A-1), B is a base represented by formula X(B-1), Ar 1 However, this represents a phenyl group, a 1-naphthalenyl group, a 2-naphthalenyl group, a 2-biphenylyl group, a 3-biphenylyl group, and a 4-biphenylyl group. Ar 2 These represent a phenyl group, a 1-naphthalenyl group, a 2-naphthalenyl group, a 2-biphenylyl group, a 3-biphenylyl group, and a 4-biphenylyl group.

[0051] Hereinafter, the triazine compound represented by formula X(1) may be referred to as triazine compound X(1). The definitions of substituents in triazine compound X(1) and preferred specific examples are as follows.

[0052] [Regarding A and B] In the case of equation X(1), A represents one of the bases selected from equations X(A-1) to X(A-9), B represents one of the bases selected from equations X(B-1) to X(B-15).

[0053] [ka]

[0054] [ka]

[0055] A represents one of the groups selected from formulas X(A-1) to X(A-9), but it is preferable that A represents one of the groups selected from formulas X(A-1) to X(A-4).

[0056] B represents any one group selected from formulas X(B-1) to X(B-15), but it is preferable that it represents any one group selected from formulas X(B-1) to X(B-4), X(B-7), X(B-8), X(B-10), and X(B-11), and it is particularly preferable that it represents any one group selected from formulas X(B-1) to X(B-4).

[0057] The combination of A and B is preferably the same group, such as the combination of the group represented by X(A-1) and the group represented by X(B-1), if the group selected for B does not contain a cyano group.

[0058] [Ar 1 ,Ar 2 [About] Ar 1 teeth, An aryl group having 6 to 30 carbon atoms may be substituted with one or more groups selected from the group consisting of C1-C12 alkyl groups, C3-C20 cycloalkyl groups, cyano groups, diarylboryl groups, and phosphine oxide groups, or Represents a pyridyl group which may be substituted with a methyl group or a phenyl group. Ar 2 teeth, An aryl group having 6 to 30 carbon atoms may be substituted with one or more groups selected from the group consisting of C1-C12 alkyl groups, C3-C20 cycloalkyl groups, cyano groups, diarylboryl groups, and phosphine oxide groups, or This represents a pyridyl group, which may be substituted with a methyl group or a phenyl group.

[0059] Ar 1 , and Ar 2In this context, preferred examples of aryl groups having 6 to 30 carbon atoms include phenyl group, 1-naphthalenyl group, 2-naphthalenyl group, 2-biphenylyl group, 3-biphenylyl group, 4-biphenylyl group, 2-(1-naphthalenyl)phenyl group, 3-(1-naphthalenyl)phenyl group, 4-(1-naphthalenyl)phenyl group, 2-(2-naphthalenyl)phenyl group, 3-(2-naphthalenyl)phenyl group, 4-(2-naphthalenyl)phenyl group, 4-phenylnaphthalen-1-yl group, 5-phenylnaphthalen-1-yl group, 6-phenylnaphthalen-2-yl group, 7-phenylnaphthalen-2-yl group, 2-phenantrenyl group, 3-phenantrenyl group, 9-phenantrenyl group, 9-anthracenyl group, p-terphenyl group, or 2-triphenylenyl group.

[0060] These groups may be substituted with C1-C12 alkyl groups, C3-C20 cycloalkyl groups, cyano groups, diarylboryl groups, and phosphine oxide groups, but are more preferably unsubstituted phenyl groups, 1-naphthalenyl groups, 2-naphthalenyl groups, 2-biphenylyl groups, 3-biphenylyl groups, and 4-biphenylyl groups, and are particularly preferably phenyl groups, 2-naphthalenyl groups, 2-biphenylyl groups, or 4-biphenylyl groups.

[0061] [Specific examples of triazine compound X(1)] Among the triazine compounds according to one aspect of the present invention represented by formula X(1), particularly preferred specific examples include X(1-1) to X(1-80) below, but the triazine compounds according to one aspect of the present invention are not limited to these.

[0062] [ka]

[0063] [ka]

[0064] [ka]

[0065] [ka]

[0066] [ka]

[0067] [ka]

[0068] [ka]

[0069] [ka]

[0070] [ka]

[0071] [ka]

[0072] [ka]

[0073] [ka]

[0074] <Triadine compound Y(1)> A triazine compound Y(1) according to one aspect of the present invention is represented by formula Y(1):

[0075] [ka]

[0076] In the case of equation Y(1), L represents one of the bases selected from equations Y(2-1) to Y(2-5).

[0077] [ka] It is most preferable that the base be one selected from formulas Y(A-1) to Y(A-10).

[0078] [ka] It is most preferable that the base be one selected from formulas Y(B-1) to Y(B-28).

[0079] [ka]

[0080] [ka] [About L] L represents one of the bases selected from equations Y(2-1) to Y(2-5).

[0081] [ka]

[0082] [Specific examples of triazine compound Y(1)] Among the triazine compounds according to one aspect of the present invention represented by formula Y(1), particularly preferred specific examples include Y(1-1) to Y(1-179) below, but the triazine compounds according to one aspect of the present invention are not limited to these.

[0083]

change

[0084]

change

[0085]

change

[0086]

change

[0087]

change

[0088]

change

[0089]

change

[0090]

change

[0091]

change

[0092]

change

[0093]

change

[0094] [ka]

[0095] [ka]

[0096] [ka]

[0097] [ka]

[0098] [ka]

[0099] [ka]

[0100] <Triadine compound Z(1)> A triazine compound according to one aspect of the present invention is represented by formula Z(1):

[0101] [ka]

[0102] In the case of equation Z(1), A represents a phenyl group, a biphenylyl group, or a naphthyl group, which may be substituted with one or more substituents selected from the group consisting of a fluorine atom, a methyl group, and a cyano group; B represents a phenyl group, a biphenylyl group, or a naphthyl group, which may be substituted with one or more substituents selected from the group consisting of a fluorine atom, a methyl group, and a cyano group; Ar 1 This represents a phenyl group or a naphthyl group, which may be substituted with one or more substituents selected from the group consisting of a fluorine atom, a methyl group, and a cyano group; Ar 2 This represents a phenyl group or a naphthyl group, which may be substituted with one or more substituents selected from the group consisting of a fluorine atom, a methyl group, and a cyano group.

[0103] [About A] A represents a phenyl group, biphenylyl group, or naphthyl group, which may be substituted with one or more groups selected from the group consisting of a fluorine atom, a methyl group, and a cyano group. In terms of facilitating the synthesis of the triazine compound represented by formula Z(1) (hereinafter also simply referred to as triazine compound Z(1)), A is preferably an unsubstituted phenyl group, biphenylyl group, or naphthyl group, and more preferably an unsubstituted phenyl group or biphenylyl group.

[0104] [Regarding B] B represents a phenyl group, biphenylyl group, or naphthyl group, which may be substituted with one or more groups selected from the group consisting of a fluorine atom, a methyl group, and a cyano group. In terms of facilitating the synthesis of the triazine compound Z(1), B is preferably an unsubstituted phenyl group, biphenylyl group, or naphthyl group, and more preferably an unsubstituted phenyl group or biphenylyl group.

[0105] [Ar 1 [About] Ar 1 This represents a phenyl group or a naphthyl group, which may be substituted with one or more substituents selected from the group consisting of a fluorine atom, a methyl group, and a cyano group. In terms of the ease of synthesis of triazine compound Z(1), Ar 1It is preferably an unsubstituted phenyl group or a naphthyl group, and more preferably an unsubstituted phenyl group.

[0106] [Ar 2 [About] Ar 2 This represents a phenyl group or a naphthyl group, which may be substituted with one or more substituents selected from the group consisting of a fluorine atom, a methyl group, and a cyano group. In terms of the ease of synthesis of triazine compound Z(1), Ar 2 It is preferable that this is an unsubstituted phenyl group or naphthyl group.

[0107] [Specific examples of triazine compound Z(1)] Among the triazine compounds according to one aspect of the present invention represented by formula Z(1), particularly preferred specific examples include the compounds represented by the following formulas Z(1-1) to Z(1-95), but the triazine compounds according to one aspect of the present invention are not limited to these.

[0108] [ka]

[0109] [ka]

[0110] [ka]

[0111] [ka]

[0112] [ka]

[0113] The uses of triazine compound (1) are described below. <Materials for organic electroluminescent devices, electron transport materials for organic electroluminescent devices> The triazine compound (1) is not particularly limited, but can be used, for example, as a material for organic electroluminescent devices. Furthermore, the triazine compound (1) can be used, for example, as an electron transport material for organic electroluminescent devices.

[0114] In other words, the material for an organic electroluminescent device according to one aspect of the present invention contains a triazine compound (1). Furthermore, the electron transport material for an organic electroluminescent device according to one aspect of the present invention also contains a triazine compound (1). The material for an organic electroluminescent device and the electron transport material for an organic electroluminescent device containing a triazine compound (1) contribute to the fabrication of organic electroluminescent devices with excellent driving voltage characteristics and current efficiency.

[0115] <Organic electroluminescent element> An organic electroluminescent device according to one aspect of the present invention comprises a triazine compound (1). The configuration of the organic electroluminescent element is not particularly limited, but for example, the configurations shown in (i) to (vi) below can be cited. (i): Anode / Emitting layer / Cathode (ii): Anode / Hole transport layer / Emitting layer / Cathode (iii): Anode / Emitting layer / Electron transport layer / Cathode (iv): Anode / Hole transport layer / Emitting layer / Electron transport layer / Cathode (v): Anode / Hole injection layer / Hole transport layer / Emitting layer / Electron transport layer / Electron injection layer / Cathode (vi): Anode / Hole injection layer / Charge generation layer / Hole transport layer / Emitting layer / Electron transport layer / Cathode

[0116] Hereinafter, an organic electroluminescent element according to one aspect of the present invention will be described in more detail with reference to Figure 1, using the configuration described in (vi) above as an example. Figure 1 is a schematic cross-sectional view showing an example of a stacked configuration of an organic electroluminescent element containing a triazine compound according to one aspect of the present invention.

[0117] The organic electroluminescent element shown in Figure 1 has a so-called bottom-emission type element configuration, but the organic electroluminescent element according to one aspect of the present invention is not limited to a bottom-emission type element configuration. That is, the organic electroluminescent element according to one aspect of the present invention may have a top-emission type element configuration or other known element configurations.

[0118] The organic electroluminescent element 100 comprises a substrate 1, an anode 2, a hole injection layer 3, a charge generation layer 4, a hole transport layer 5, a light-emitting layer 6, an electron transport layer 7, and a cathode 8 in this order. However, some of these layers may be omitted, or other layers may be added. For example, an electron injection layer may be provided between the electron transport layer 7 and the cathode 8, the charge generation layer 4 may be omitted, and the hole transport layer 5 may be directly provided on the hole injection layer 3.

[0119] Furthermore, the configuration may include a single layer that combines the functions of multiple layers, such as an electron injection / transport layer that combines the functions of both an electron injection layer and an electron transport layer, instead of the multiple layers themselves. In addition, for example, a single-layer hole transport layer 5 and a single-layer electron transport layer 7 may each consist of multiple layers.

[0120] [Layer containing a triazine compound represented by formula (1)] The organic electroluminescent device contains a triazine compound represented by formula (1) in one or more layers selected from the group consisting of an emissive layer and a layer between the emissive layer and the cathode. Therefore, in the example configuration shown in Figure 1, the organic electroluminescent device 100 contains the triazine compound (1) in at least one layer selected from the group consisting of an emissive layer 6 and an electron transport layer 7.

[0121] In particular, it is preferable that the electron transport layer 7 contains the triazine compound (1). The triazine compound (1) may be included in multiple layers of the organic electroluminescent device, and if an electron injection layer is provided between the electron transport layer and the cathode, the electron injection layer may also contain the triazine compound (1). In the following, we will describe an organic electroluminescent device 100 in which the electron transport layer 7 contains a triazine compound (1).

[0122] [Circuit board 1] There are no particular limitations on the substrate; for example, glass plates, quartz plates, and plastic plates can be used. Also, in a configuration where light is extracted from the substrate 1, the substrate 1 is transparent to the wavelength of light.

[0123] Examples of light-transmitting plastic films include films made from polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), polyetherimide, polyetheretherketone, polyphenylene sulfide, polyarylate, polyimide, polycarbonate (PC), cellulose triacetate (TAC), cellulose acetate propionate (CAP), and the like.

[0124] [Anode 2] An anode 2 is provided on substrate 1 (on the side of hole injection layer 3). In the case of an organic electroluminescent device in which light is extracted by passing it through an anode, the anode is formed of a material that allows the light to pass through or substantially allows the light to pass through.

[0125] Transparent materials used for the anode are not particularly limited, but examples include indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide, aluminum-doped tin oxide, magnesium-indium oxide, nickel-tungsten oxide, other metal oxides, metal nitrides such as gallium nitride, metal selenides such as zinc selenide, and metal sulfides such as zinc sulfide. In the case of an organic electroluminescent device that extracts light only from the cathode, the transmission characteristics of the anode are not important. Therefore, examples of materials that can be used for the anode in this case include gold, iridium, molybdenum, palladium, and platinum. A buffer layer (electrode interface layer) may be provided on the anode.

[0126] [Hole injection layer 3, hole transport layer 5] Between the anode 2 and the light-emitting layer 6 (described later), a hole injection layer 3, a charge generation layer 4 (described later), and a hole transport layer 5 are provided in this order from the anode 2 side. The hole injection layer and hole transport layer have the function of transferring holes injected from the anode to the light-emitting layer. By interposing these hole injection and hole transport layers between the anode and the light-emitting layer, a larger number of holes can be injected into the light-emitting layer at a lower electric field.

[0127] Furthermore, the hole injection layer and hole transport layer also function as electron barrier layers. That is, electrons injected from the cathode and transported from the electron injection layer and / or electron transport layer to the light-emitting layer are prevented from leaking into the hole injection layer and / or hole transport layer by the electron barrier present at the interface between the light-emitting layer and the hole injection layer and / or hole transport layer. As a result, these electrons accumulate at the interface within the light-emitting layer, leading to effects such as improved current efficiency, and resulting in an organic electroluminescent element with excellent light-emitting performance.

[0128] The hole injection layer and hole transport layer materials must possess at least one of the following properties: hole injection properties, hole transport properties, or electron barrier properties. The hole injection layer and hole transport layer materials may be either organic or inorganic.

[0129] Specific examples of materials for the hole injection layer and hole transport layer include triazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives, pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, aminosubstituted chalcone derivatives, oxazole derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives, aniline copolymers, conductive polymer oligomers (especially thiophene oligomers), porphyrin compounds, aromatic tertiary amine compounds, and styrylamine compounds. Among these, porphyrin compounds, aromatic tertiary amine compounds, and styrylamine compounds are preferred, with aromatic tertiary amine compounds being particularly preferred.

[0130] Specific examples of aromatic tertiary amine compounds and styrylamine compounds include N,N,N',N'-tetraphenyl-4,4'-diaminophenyl, N,N'-diphenyl-N,N'-bis(3-methylphenyl)-[1,1'-biphenyl]-4,4'-diamine (TPD), 2,2-bis(4-di-p-tolylaminophenyl)propane, 1,1-bis(4-di-p-tolylaminophenyl)cyclohexane, N,N,N',N'-tetra-p-tolyl-4,4'-diaminobiphenyl, 1,1-bis(4-di-p-tolylaminophenyl)-4-phenylcyclohexane, bis(4-dimethylamino-2-methylphenyl)phenylmethane, bis(4-di-p-tolylaminophenyl)phenylmethane, N,N'-diphenyl-N,N'- Examples include di(4-methoxyphenyl)-4,4'-diaminobiphenyl, N,N,N',N'-tetraphenyl-4,4'-diaminodiphenyl ether, 4,4'-bis(diphenylamino)quadriphenyl, N,N,N-tri(p-tolyl)amine, 4-(di-p-tolylamino)-4'-[4-(di-p-tolylamino)styryl]stilbene, 4-N,N-diphenylamino-(2-diphenylvinyl)benzene, 3-methoxy-4'-N,N-diphenylaminostilbenzene, N-phenylcarbazole, 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (NPD), and 4,4',4''-tris[N-(3-methylphenyl)-N-phenylamino]triphenylamine (MTDATA). In addition, inorganic compounds such as p-type Si and p-type SiC can also be cited as examples of materials for hole injection layers and hole transport layers.

[0131] The hole injection layer and hole transport layer may be a single-layer structure made of one or more materials, or a laminated structure made of multiple layers of the same or different compositions.

[0132] [Charge generation layer 4] A charge generation layer 4 may be provided between the hole injection layer 3 and the hole transport layer 5. There are no particular restrictions on the material of the charge generation layer, but examples include dipyrazino[2,3-f:2',3'-h]quinoxaline-2,3,6,7,10,11-hexacarbonnitrile (HAT-CN). The charge generation layer may be a single-layer structure made of one or more materials, or it may be a laminated structure made of multiple layers of the same or different compositions.

[0133] [Emitting layer 6] A light-emitting layer 6 is provided between the hole transport layer 5 and the electron transport layer 7, which will be described later. Materials for the light-emitting layer include phosphorescent materials, fluorescent materials, and thermally activated delayed fluorescence materials. In the light-emitting layer, electron-hole pairs recombine, resulting in light emission.

[0134] The luminescent layer may consist of a single low-molecular-weight material or a single polymer material, but more commonly, it consists of a host material doped with a guest compound. The luminescence primarily arises from the dopant and can have any color.

[0135] Examples of host materials include compounds having biphenyl groups, fluorenyl groups, triphenylsilyl groups, carbazole groups, pyrenyl groups, and anthryl groups. More specifically, examples include DPVBi (4,4'-bis(2,2-diphenylvinyl)-1,1'-biphenyl), BCzVBi (4,4'-bis(9-ethyl-3-carbazovinylene)1,1'-biphenyl), TBADN (2-tert-butyl-9,10-di(2-naphthyl)anthracene), ADN (9,10-di(2-naphthyl)anthracene), CBP (4,4'-bis(carbazol-9-yl)biphenyl), CDBP (4,4'-bis(carbazol-9-yl)-2,2'-dimethylbiphenyl), 2-(9-phenylcarbazol-3-yl)-9-[4-(4-phenylphenylquinazoline-2-yl)carbazol, 9,10-bis(biphenyl)anthracene, etc.

[0136] Examples of fluorescent dopants include anthracene, pyrene, tetracene, xanthene, perylene, rubrene, coumarin, rhodamine, quinacridone, dicyanomethylenepyran compounds, thiopyran compounds, polymethine compounds, pyrylium, thiapyrillium compounds, fluorene derivatives, perifurante derivatives, indenoperylene derivatives, bis(azinyl)amineboron compounds, bis(azinyl)methane compounds, carbostyryl compounds, etc. A fluorescent dopant may be a combination of two or more selected from these.

[0137] Examples of phosphorescent dopants include organometallic complexes of transition metals such as iridium, platinum, palladium, and osmium.

[0138] Specific examples of fluorescent dopants and phosphorescent dopants include Alq3 (tris(8-hydroxyquinoline)aluminum), DPAVBi (4,4'-bis[4-(di-p-tolylamino)styryl]biphenyl), perylene, bis[2-(4-n-hexylphenyl)quinoline](acetylacetonate)iridium(III), Ir(PPy)3 (tris(2-phenylpyridine)iridium(III)), and FIrPic (bis(3,5-difluoro-2-(2-pyridyl)phenyl-(2-carboxypyridyl)iridium(III))).

[0139] Furthermore, the light-emitting material is not limited to being contained only in the light-emitting layer. For example, the light-emitting material may also be contained in layers adjacent to the light-emitting layer (hole transport layer 5 or electron transport layer 7). This can further increase the current efficiency of the organic electroluminescent device.

[0140] The light-emitting layer may be a single-layer structure made of one or more materials, or it may be a laminated structure made of multiple layers of the same or different compositions.

[0141] [Electron transport layer 7] An electron transport layer 7 is provided between the light-emitting layer 6 and the cathode 8, which will be described later. The electron transport layer has the function of transferring electrons injected from the cathode to the light-emitting layer. By interposing the electron transport layer between the cathode and the light-emitting layer, electrons are injected into the light-emitting layer at a lower electric field.

[0142] As mentioned above, the electron transport layer preferably contains a triazine compound represented by formula (1) above.

[0143] Furthermore, the electron transport layer may also contain conventionally known electron transport materials in addition to the triazine compound (1). Examples of conventionally known electron transport materials include lithium 8-hydroxyquinolinate (Liq), bis(8-hydroxyquinolinate)zinc, bis(8-hydroxyquinolinate)copper, bis(8-hydroxyquinolinate)manganese, tris(8-hydroxyquinolinate)aluminum, tris(2-methyl-8-hydroxyquinolinate)aluminum, tris(8-hydroxyquinolinate)gallium, bis(10-hydroxybenzo[h]quinolinate)beryllium, bis(10-hydroxybenzo[h]quinolinate)zinc, bis(2-methyl-8-quinolinate)chlorogallium, bis(2-methyl-8-quinolinate)(o-crezolate)gallium, and bis(2-methyl-8-quinolinate)-1-naphtholate. Examples include aluminum, or bis(2-methyl-8-quinolinate)-2-naphtholate gallium, 2-[3-(9-phenantrenyl)-5-(3-pyridinyl)phenyl]-4,6-diphenyl-1,3,5-triazine, and 2-(4,''-di-2-pyridinyl[1,1':3',1''-terphenyl]-5-yl)-4,6-diphenyl-1,3,5-triazine, BCP (2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline), Bphen (4,7-diphenyl-1,10-phenanthroline), BAlq (bis(2-methyl-8-quinolinate)-4-(phenylphenolate)aluminum), and bis(10-hydroxybenzo[h]quinolinate)beryllium).

[0144] The electron transport layer may be a single-layer structure made of one or more materials, or it may be a laminated structure made of multiple layers of the same or different compositions. When the electron transport layer has a two-layer structure with the first electron transport layer on the light-emitting layer side and the second electron transport layer on the cathode side, it is preferable that the second electron transport layer contains a triazine compound (1).

[0145] [Cathode 8] A cathode 8 is provided on the electron transport layer 7. In the case of an organic electroluminescent element configured to extract only the light emitted after passing through the anode, the cathode can be formed from any conductive material. Examples of cathode materials include sodium, sodium-potassium alloys, magnesium, lithium, magnesium / copper mixtures, magnesium / silver mixtures, magnesium / aluminum mixtures, magnesium / indium mixtures, aluminum / aluminum oxide (Al2O3) mixtures, indium, lithium / aluminum mixtures, and rare earth metals. A buffer layer (electrode interface layer) may be provided on the cathode (electron transport layer side).

[0146] [Method of forming each layer] Each layer, excluding the electrodes (anode and cathode) described above, can be formed by thinning the material of each layer (along with binder resins and solvents as needed) using known methods such as vacuum deposition, spin coating, casting, or the LB (Langmuir-Blodgett method). There are no particular restrictions on the thickness of each layer formed in this way, and it can be selected as appropriate depending on the situation, but it is usually in the range of 5 nm to 5 μm.

[0147] The anode and cathode can be formed by thinning the electrode material using methods such as vapor deposition or sputtering. The pattern may be formed via a mask of the desired shape during vapor deposition or sputtering, or the pattern may be formed by photolithography after the thin film has been formed by vapor deposition or sputtering.

[0148] The film thickness of the anode and cathode is preferably 1 μm or less, and more preferably 10 nm to 200 nm.

[0149] An organic electroluminescent element according to one aspect of the present invention may be used as a type of lamp, such as for illumination or as an exposure light source, or as a projection device that projects images, or as a display device that directly displays still or moving images. When used as a display device for video playback, the driving method may be either a simple matrix (passive matrix) method or an active matrix method. Furthermore, by using two or more organic electroluminescent elements of this embodiment having different emission colors, it is possible to create a full-color display device.

[0150] Furthermore, the triazine compound (1) according to one aspect of the present invention can be synthesized by appropriately combining known reactions (for example, the Suzuki-Miyaura cross-coupling reaction). [Examples]

[0151] The present invention will be described in more detail below based on examples, but the present invention is not to be limited in any way by these examples.

[0152] 1 1H-NMR measurements were performed using a Gemini200 (Varian). FDMS measurements were performed using a Hitachi M-80B. The glass transition temperature was measured using a DSC7020 (manufactured by Hitachi High-Tech Science Corporation). For DSC measurements, aluminum oxide (Al2O3) was used as the reference, and the sample was measured in 10 mg units. As a pretreatment before measurement, the sample was heated from 30°C to above its melting point at a rate of 10°C / min to melt it, and then rapidly cooled by contacting the sample with dry ice. Subsequently, the pretreated sample was heated from 30°C at a rate of 10°C / min, and the glass transition temperature was measured. The light-emitting characteristics of the organic electroluminescent device were evaluated at room temperature (23°C, 50% RH) by applying a direct current to the fabricated device and using a luminance meter (product name: BM-9, manufactured by Topcon Technology House Co., Ltd.).

[0153] <Triazine compound X(1)> Synthesis Example of X - Synthesis of Compound X(1-2)

[0154]

Chemical formula

[0155] Under a nitrogen stream, 1,4-dioxane (69 ml) was added to a flask containing 1-chloro-2,5-di(naphthalen-2-yl)benzene (5.0 g, 13.7 mmol), bis(pinacolato)diboron (5.2 g, 20.6 mmol), PdCl2[(Pcy3)]2 (202 mg, 0.27 mmol), and potassium acetate (4.0, 41.1 mmol), and the mixture was stirred at 100°C for 21 hours. After allowing to cool to room temperature, the solid was collected from the reaction solution by suction filtration and washed with 1,4-dioxane. The obtained solid was recrystallized from a methanol (100 ml) solution to obtain a solid (yield 5.1 g) of 2-[2,5-di(naphthalen-2-yl)phenyl]-4,4,5,5-tetramethyl-1,3,2-dioxaborolane.[[ID=二十]] [[ID=二十一]]

[0156] [[ID=二十二]] Under a nitrogen atmosphere, tetrahydrofuran (191 ml) was added to a flask containing 2-chloro-4,6-di(biphenyl-4-yl)-1,3,5-triazine (4.0 g, 9.5 mmol), 2-[2,5-di(naphthalene-2-yl)phenyl]-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (4.8 g, 10.5 mmol), and Pd(PPh3)4 (220 mg, 0.19 mmol). Further, 2M potassium phosphate aqueous solution (14 ml, 28.6 mmol) was added, and the mixture was stirred at 70°C for 22 hours. After cooling to room temperature, the precipitated solid was collected by suction filtration, and the obtained solid was washed with water and acetone. The obtained solid was dissolved in toluene (2000 ml), activated carbon (1.2 g) was added, and the mixture was heated and stirred at 100°C for 1 hour. The activated carbon was filtered off by suction filtration using a Kiriyama funnel lined with Celite, and the filtrate was recrystallized to obtain a white solid of compound X(1-2) (yield 4.5g). The glass transition temperature was 116°C. 1 H-NMR(CDCl3)δ(ppm):8.85(m,1H),8.26(m,5H),7.90-8.10(m,7H),7.72-7.86(m,3H),7.44-7.65(m,16H),7.39(m,3H).

[0157] Synthesis Example of X - 2 Synthesis of Compound X(1-4)

[0158] [ka]

[0159] Under a nitrogen atmosphere, tetrahydrofuran (110 ml) was added to a flask containing 2-chloro-4,6-di(biphenyl-4-yl)-1,3,5-triazine (2.3 g, 5.5 mmol), 2-[4-(9-phenantrenyl)[1,1'-biphenyl]-2-yl]-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (3.0 g, 6.57 mmol), and Pd(PPh3)4 (127 mg, 0.11 mmol). Further, 2 M aqueous potassium phosphate (8 ml, 16.4 mmol) was added, and the mixture was stirred at 70°C for 20 hours. After cooling to room temperature, water and toluene were added and the mixture was separated. After removing the solvent under reduced pressure, water was added, and the precipitated solid was collected by suction filtration. The obtained solid was washed with water and acetone. The obtained solid was dissolved in toluene (250 ml), activated carbon (0.4 g) was added, and the mixture was heated and stirred at 100°C for 1 hour. The activated carbon was filtered off by suction filtration using a Kiriyama funnel lined with Celite, and the solvent was removed by distillation under reduced pressure. Recrystallization of the toluene / 1-butanol mixed solution yielded a white solid of compound X(1-4) (yield 1.5 g). The glass transition temperature was 137°C. 1 H-NMR(CDCl3)δ(ppm):8.84(d,1H),8.78(d,1H),8.56(m,1H),8.40(m,4H),8.10(d, 1H),7.98(d,1H),7.87(s,1H),7.81(m,1H),7.58-7.73(m,13H),7.31-7.50(m,11H).

[0160] Synthesis Example of X - 3 Synthesis of Compound X(1-5)

[0161] [ka] The same experimental procedure as in Synthesis Example-2 for compound X was performed, except that 2-[4-(9-phenantrenyl)[1,1'-biphenyl]-2-yl]-4,4,5,5-tetramethyl-1,3,2-dioxaborolane was replaced with 2-[4-(naphthalene-2-yl)[1,1'-biphenyl]-2-yl]-4,4,5,5-tetramethyl-1,3,2-dioxaborolane, to obtain a white solid of compound X(1-5) (yield 2.5g). FDMS:663

[0162] Synthesis Example of Compound X-4: Synthesis of Compound X(1-75)

[0163] [ka] The same experimental procedure as in Synthesis Example-2 for compound X was performed, except that 2-[4-(9-phenantrenyl)[1,1'-biphenyl]-2-yl]-4,4,5,5-tetramethyl-1,3,2-dioxaborolane was replaced with 2-[4-(naphthalene-2-yl)[1,1':4',1''-terphenyl]-2'-yl]-4,4,5,5-tetramethyl-1,3,2-dioxaborolane], to obtain a white solid of compound X(1-75) (yield 1.4g). 1 H-NMR(CDCl3)δ(ppm):8.69(d,J=2.0Hz,1H),8.47-8.41(m,5H),8.03(d,J=9.2Hz,1H),7.96-7.88(m,5H),7.7 2(dd,J=3.6Hz,3.6Hz,2H),7.69-7.61(m,8H),7.58-7.54(m,2H),7.52(brd,J=1.6Hz,1H),7.50-7.37(m,12H).

[0164] Synthesis Example of X - 5 Synthesis of Compound X(1-80)

[0165] [ka] The same experimental procedure as in Synthesis Example-2 of compound X was performed, except that 2-chloro-4,6-di(biphenyl-4-yl)-1,3,5-triazine was replaced with 6-chloro-2-[(1,1'-biphenyl)-2-yl]-4-[(1,1'-biphenyl)-4-yl]-1,3,5-triazine, to obtain a white solid of compound X(1-80) (yield 3.0 g). The glass transition temperature of compound X(1-80) was 125°C. 11H-NMR (CDCl3) δ (ppm): 8.86 (d, J = 9.2 Hz, 1H), 8.81 (d, J = 8.0 Hz, 1H), 7.98 (brd, J = 6.0 Hz, 1H), 7.88 (brd, J = 8.0 Hz, 1H), 7.84 - 7.79 (m, 2H), 7.79 (d, J = 1.6 Hz, 1H), 7.76 - 7.66 (m, 5H), 7.63 - 7.57 (m, 4H), 7.54 - 7.32 (m, 14H), 7.13 (dd, J = 8.0 Hz, 1.2 Hz, 2H), 6.81 (brt, J = 7.2 Hz, 2H), 6.42 (brt, J = 7.6 Hz, 1H).

[0166] <Triazine compound Y(1)> Y Synthesis Example - 1 Synthesis of Compound Y(1 - 96)

[0167] [Chemical formula]

[0168] Under a nitrogen stream, tetrahydrofuran (170 mL) was added to a flask containing 2,4-bis([1,1'-biphenyl]-4-yl)-6-[4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan -2-yl)phenyl]-1,3,5-triazine (10.0 g, 17.02 mmol), 2,3-dichlorobromobenzene (4.2 g, 18.72 mmol), and Pd(PPh3)4 (393 mg, 0.34 mmol). Further, 2 M aqueous potassium phosphate solution (25.5 mL, 51.06 mmol) was added, and the mixture was stirred at 70 °C for 24 hours. After allowing to cool to room temperature, the precipitated solid was collected by suction filtration and washed with water and then methanol. After dissolving the obtained solid in toluene, recrystallization was carried out to obtain 2,4-bis([1,1'-biphenyl]-4-yl)-6-(2',3'-dichloro[1,1'-biphenyl]-4-yl)-1,3,5-triazine (yield 9.1 g, yield 88%).

[0169] Under a nitrogen stream, tetrahydrofuran (300 ml) was added to a flask containing 2,4-bis([1,1'-biphenyl]-4-yl)-6-(2',3'-dichloro[1,1'-biphenyl]-4-yl-1,3,5-triazine (9.1 g, 15.05 mmol), phenylboronic acid (12.8 g, 105.4 mmol), palladium acetate (68 mg, 0.30 mmol), and 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl (X-Phos) (287 mg, 0.60 mmol). Furthermore, 2M potassium phosphate was added. A 38 ml, 75.3 mmol aqueous solution of ammonium phosphate was added, and the mixture was stirred at 70°C for 90 hours. After cooling to room temperature, the precipitated solid was collected by suction filtration and washed with water and ethanol. The obtained solid was dissolved in toluene (1000 mL), activated carbon (1.2 g) was added, and the mixture was heated and stirred at 100°C for 2 hours. The activated carbon was filtered off by suction filtration using a Kiriyama funnel lined with Celite, and the filtrate was removed by reduced pressure distillation. Further recrystallization from a toluene (800 ml) solution yielded a white solid of compound Y(1-96) (yield 6.9 g, yield 66%). The glass transition temperature was 158°C. 1 H-NMR(CDCl3)δ(ppm):8.83(d,4H),8.62(d,2H),7.80(d,4H),7.71(d,4H),7.47-7.57(m,7H),7 .42(m,2H),7.32(d,2H),7.17(m,3H),7.08-7.13(m,2H),6.98-7.05(m,3H),6.89-6.94(m,2H).

[0170] Y Synthesis Example-2: Synthesis of Compound Y(1-180)

[0171] [ka]

[0172] Under a nitrogen atmosphere, 270 ml of tetrahydrofuran was added to a flask containing 2-[(1,1'-biphenyl)-4-yl]-4-(naphthalene-2-yl)-6-[3'-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]-1,3,5-triazine (15.0 g, 26.7 mmol), {(1,1':2',1''-terphenyl)-3'-yl}triflomethanesulfonate (11.1 g, 29.4 mmol), and Pd(PPh3)4 (927 mg, 0.801 mmol). Further, 40.1 ml of 2 M potassium phosphate aqueous solution was added, and the mixture was stirred at 70°C for 26 hours. After cooling to room temperature, the precipitated solid was collected by suction filtration, and the obtained solid was washed with water and acetone. The obtained solid was dissolved in chlorobenzene (800 ml), activated carbon (3.2 g) was added, and the mixture was heated and stirred at 100°C for 1 hour. The activated carbon was filtered off by suction filtration using a Kiriyama funnel lined with Celite, and the filtrate was removed by reduced pressure distillation. Further recrystallization from a chlorobenzene (700 ml) solution yielded a white solid of compound Y(1-180) (yield 13.9 g). The glass transition temperature of compound Y(1-180) was 11°C. 1 H-NMR(CDCl3)δ(ppm):6.95-7.04(m,5H),7.14-7.23(m,5H),7.31-7.33(m,1 H),7.38-7.45(m,2H),7.50-7.65(m,7H),7.74(d,J=7.7Hz,2H),7.83(d,J=8. 5Hz,2H),7.94-7.96(m,1H),8.03(d,J=8.7Hz,1H),8.11-8.13(m,1H),8.64-8 .67(m,2H),8.8(dd,J=8.5Hz,1.7Hz,1H),8.86(d,J=8.7Hz,2H),9.32(s,1H).

[0173] <Triadine compound Z(1)> Z Synthesis Example-1: Synthesis of Compound Z(1-2)

[0174] [ka]

[0175] Under a nitrogen atmosphere, tetrahydrofuran (51 ml) was added to a flask containing 2,4-bis[(1,1'-biphenyl)-4-yl]-6-[3'-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]-1,3,5-triazine (3.0 g, 5.1 mmol), {(1,1':3',1''-terphenyl)-4'-yl}triflomethanesulfonate (2.1 g, 5.6 mmol), and Pd(PPh3)4 (133 mg, 0.12 mmol). Further, 2 M potassium phosphate aqueous solution (7.7 ml, 16.0 mmol) was added, and the mixture was stirred at 70°C for 20 hours. After cooling to room temperature, the precipitated solid was collected by suction filtration, and the obtained solid was washed with water and acetone. The obtained solid was dissolved in toluene (500 ml), activated carbon (0.5 g) was added, and the mixture was heated and stirred at 100°C for 1 hour. The activated carbon was filtered off by suction filtration using a Kiriyama funnel lined with Celite, and the filtrate was recrystallized to obtain a white solid of compound Z(1-2) (yield 3.0 g). The glass transition temperature of compound Z(1-2) was 119°C. 1 H-NMR(CDCl3)δ(ppm):8.84-8.79(m,4H),8.71(t,J=12.0Hz,1H),8.64-8.69(m,1 H),7.79-7.84(m,4H),7.68-7.77(m,9H),7.27-7.67(m,15H),7.18-7.24(m,1H).

[0176] Z Synthesis Example-2: Synthesis of Compound Z(1-13)

[0177] [ka] The experimental procedure was the same as in Synthesis Example-1 of Z, except that 2,4-bis[(1,1'-biphenyl)-4-yl]-6-[3'-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]-1,3,5-triazine was replaced with 2-[(1,1'-biphenyl)-2-yl]-4-[(1,1'-biphenyl)-4-yl]-6-[3'-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]-1,3,5-triazine], and a white solid of compound Z(1-13) (yield 4.4 g) was obtained. The glass transition temperature of compound Z(1-13) was 107°C. FDMS:689

[0178] Z Synthesis Example-3: Synthesis of Compound Z(1-15)

[0179] [ka] The experimental procedure was the same as in Synthesis Example-1 of compound Z, except that 2,4-bis[(1,1'-biphenyl)-4-yl]-6-[3'-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]-1,3,5-triazine was replaced with 2-[(1,1'-biphenyl)-2-yl]-6-(naphthalene-2-yl)-4-[3'-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]-1,3,5-triazine, and a white solid of compound Z(1-15) (yield 9.7) was obtained. The glass transition temperature of compound Z(1-15) was 112°C. 1H-NMR(CDCl3) δ (ppm): 7.20 (t, J = 7.4 Hz, 1H), 7.28 (t, J = 7.3 Hz, 2H), 7.33 - 7.53 (m, 10H), 7.56 - 7.63 (m, 2H), 7.70 - 7.77 (m, 7H), 7.83 (d, J = 8.6 Hz, 2H), 7.94 - 7.96 (m, 1H), 8.02 (d, J = 8.7 Hz, 1H), 8.11 - 8.13 (m, 1H), 8.70 (dt, J = 7.4 Hz, 1.7 Hz, 1H), 8.75 (t, J = 1.5 Hz, 1H), 8.79 (dd, J = 8.7 Hz, 1.5 Hz, 1H), 8.85 (d, J = 8.5 Hz, 2H), 9.31 (s, 1H).

[0180] Next, device evaluation was carried out using the obtained compound.

[0181] <Example of X device - 1 (see Figure 2)> (Preparation of substrate 101 and anode 102) As a substrate provided with an anode on its surface, a glass substrate with an indium tin oxide (ITO) film (film thickness 110 nm) with a width of 2 mm patterned in a stripe shape was prepared. Then, this substrate was washed with isopropyl alcohol and then surface - treated by ozone - ultraviolet cleaning.

[0182] (Preparation for vacuum evaporation) On the substrate subjected to surface treatment after washing, vacuum evaporation of each layer was carried out by the vacuum evaporation method to form each layer by lamination. First, the glass substrate was introduced into the vacuum evaporation chamber and evacuated to 1.0×10 -4 Pa. Then, each layer was fabricated according to the film - forming conditions of each layer in the following order.

[0183] (Fabrication of hole - injection layer 103) Sublimation - purified N - [1,1'-biphenyl]-4 - yl - 9,9 - dimethyl - N - [4-(9 - phenyl - 9H - carbazol - 3 - yl)phenyl]-9H - fluorene - 2 - amine and 1,2,3 - tris[(4 - cyano - 2,3,5,6 - tetrafluorophenyl)methylene]cyclopropane were formed into a 10 - nm film at a rate of 0.15 nm / second to fabricate the hole - injection layer 103.

[0184] (Preparation of the first hole transport layer 1051) N-[1,1'-biphenyl]-4-yl-9,9-dimethyl-N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-9H-fluoren-2-amine, purified by sublimation, was deposited at a rate of 0.15 nm / second to create a first hole transport layer 1051 with a thickness of 85 nm.

[0185] (Preparation of the second hole transport layer 1052) N-phenyl-N-(9,9-diphenylfluoren-2-yl)-N-(1,1'-biphenyl-4-yl)amine, purified by sublimation, was deposited as a 5 nm film at a rate of 0.15 nm / second to create the second hole transport layer 1052. Based on the above, a hole transport layer 105 with a two-layer laminated structure consisting of a first hole transport layer 1051 and a second hole transport layer 1052 was fabricated.

[0186] (Fabrication of the light-emitting layer 106) A luminescent layer 106 was fabricated by depositing 3-(10-phenyl-9-anthryl)-dibenzofuran and 2,7-bis[N,N-di-(4-tertbutylphenyl)]amino-bisbenzofuran-9,9'-spirofluorene at a ratio of 95:5 (mass ratio) to a film with a wavelength of 20 nm. The deposition rate was 0.18 nm / second.

[0187] (Fabrication of the first electron transport layer 1071) The first electron transport layer 1071 was fabricated by depositing a 6 nm film of sublimation-purified 2-[3'-(9,9-dimethyl-9H-fluoren-2-yl)[1,1'-biphenyl]-3-yl]-4,6-diphenyl-1,3,5-triazine at a rate of 0.05 nm / second.

[0188] (Fabrication of the second electron transport layer 1072) Compound X(1-2) synthesized in X Synthesis Example-1 and Liq were deposited in a 50:50 (mass ratio) ratio at a 25 nm film to create the second electron transport layer 1072. The deposition rate was 0.15 nm / second. Based on the above, an electron transport layer 107 with a two-layer stacked structure consisting of a first electron transport layer 1071 and a second electron transport layer 1072 was fabricated.

[0189] (Fabrication of cathode 108) Finally, a metal mask was positioned perpendicular to the ITO stripes on the substrate, and cathode 108 was deposited. The cathode consisted of two layers: silver / magnesium (mass ratio 1 / 10) and silver, deposited in that order at 80 nm and 20 nm, respectively. The deposition rate for silver / magnesium was 0.5 nm / second, and the deposition rate for silver was 0.2 nm / second.

[0190] As a result, the light-emitting area is 4 mm² as shown in Figure 2. 2 Organic electroluminescent devices 100 were fabricated. The film thickness of each device was measured using a stylus-type film thickness analyzer (DEKTAK, Bruker).

[0191] Furthermore, this element was sealed in a nitrogen atmosphere glove box with oxygen and moisture concentrations of 1 ppm or less. The sealing was performed using bisphenol F type epoxy resin (manufactured by Nagase ChemteX Corporation) to seal the glass sealing cap and the film-deposited substrate (element).

[0192] A DC current was applied to the organic electroluminescent element fabricated as described above, and its luminescence characteristics were evaluated using a luminance meter (product name: BM-9, manufactured by Topcon Techno House). The luminescence characteristics were measured with a current density of 10 mA / cm². 2 The current efficiency (cd / A), drive voltage (V), and element lifespan (h) during continuous operation were measured when a current was applied. The element lifespan (h) was measured using the fabricated element at an initial brightness of 1000 cd / m². 2 The brightness decay time during continuous lighting when driven by was measured, and the brightness (cd / m²) was measured. 2 The time required for the value to decrease by 5% was measured. Note that the current efficiency, drive voltage, and element lifespan (h) during continuous operation shown in Tables 1-3 are relative values ​​with the results from X-element Reference Example 1, Y-element Reference Example 1, and Z-element Reference Example 1 set as the baseline value (100). The obtained measurement results are shown in Tables 1-3.

[0193] <Example of X element - 2> In Example of X element - 1, an organic electroluminescent device was fabricated and evaluated in the same manner as in Example of X element - 1, except that compound X(1 - 4) was used instead of compound X(1 - 2). The obtained measurement results are shown in Table 1.

[0194] <Example of X element - 3> In Example of X element - 1, an organic electroluminescent device was fabricated and evaluated in the same manner as in Example of X element - 1, except that compound X(1 - 5) synthesized in Synthesis Example of X - 3 was used instead of compound X(1 - 2). The obtained measurement results are shown in Table 1.

[0195] <Example of X element - 4> In Example of X element - 1, an organic electroluminescent device was fabricated and evaluated in the same manner as in Example of X element - 1, except that compound X(1 - 75) synthesized in Synthesis Example of X - 4 was used instead of compound X(1 - 2). The obtained measurement results are shown in Table 1.

[0196] <Example of X element - 5> In Example of X element - 1, an organic electroluminescent device was fabricated and evaluated in the same manner as in Example of X element - 1, except that compound X(1 - 80) synthesized in Synthesis Example of X - 5 was used instead of compound X(1 - 2). The obtained measurement results are shown in Table 1.

[0197] <Reference Example of X element - 1> In Example of X element - 1, an organic electroluminescent device was fabricated and evaluated in the same manner as in Example of X element - 1, except that compound 24 described in Patent Document 1 was used instead of compound X(1 - 2). The obtained measurement results are shown in Table 1.

[0198]

Chemical formula

[0199]

Table 1

[0200] <Example of Y element - 1 (see Fig. 2)> In Example - 1 of the X element, an organic electroluminescent device was fabricated and evaluated in the same manner as in Example - 1 of the X element, except that compound Y(1 - 96) synthesized in Synthesis Example - 1 of Y was used instead of compound X(1 - 2). The obtained measurement results are shown in Table 2. <Example of Y element - 2 (see Fig. 2)> In Example - 1 of the X element, an organic electroluminescent device was fabricated and evaluated in the same manner as in Example - 1 of the X element, except that compound Y(1 - 180) synthesized in Synthesis Example - 2 of Y was used instead of compound X(1 - 2). The obtained measurement results are shown in Table 2.

[0201] <Reference Example of Y element - 1> In Example - 1 of the Y element, an organic electroluminescent device was fabricated and evaluated in the same manner as in Example - 1 of the X element, except that the compound disclosed in Example - 9 of Patent Document 2 (Japanese Patent Laid - Open No. 2018 - 95562) was used instead of compound Y(1 - 96). The obtained measurement results are shown in Table 2.

[0202]

Chemical formula

[0203]

Table 2

[0204] <Example of Z element - 1 (see Fig. 2)> In Example - 1 of the X element, an organic electroluminescent device was fabricated and evaluated in the same manner as in Example - 1 of the X element, except that compound Z(1 - 2) synthesized in Synthesis Example - 1 of Z was used instead of compound X(1 - 2). The obtained measurement results are shown in Table 3.

[0205] <Example of Z element - 2> In Example - 1 of the X element, an organic electroluminescent device was fabricated and evaluated in the same manner as in Example - 1 of the X element, except that compound Z(1 - 13) synthesized in Synthesis Example - 2 of Z was used instead of compound X(1 - 2). The obtained measurement results are shown in Table 3.

[0206] <Example of Z element - 3> In Example - 1 of the X element, an organic electroluminescent device was fabricated and evaluated in the same manner as in Example - 1 of the X element, except that compound Z(1 - 15) synthesized in Synthesis Example - 3 of Z was used instead of compound X(1 - 2). The obtained measurement results are shown in Table 3.

[0207] <Reference Example of Z element - 1> In Example - 1 of the Z element, an organic electroluminescent device was fabricated and evaluated in the same manner as in Example - 1 of the X element, except that the following compound (ETL - 1) described in Patent Document 1 (International Publication No. 2015 / 111848) was used instead of compound Z(1 - 2). The obtained measurement results are shown in Table 3.

[0208]

Chemical formula

[0209]

Table 3

[0210] The triazine compound (1) according to one aspect of the present invention has a wide bandgap and a high triplet excitation level, and thus can be suitably used not only for conventional fluorescent device applications but also for organic electroluminescent devices utilizing phosphorescence or thermally activated delayed fluorescence (TADF).

Explanation of symbols

[0211] 1,101 Substrate 2,102 Anode 3,103 Hole injection layer 4,104 Charge generation layer 5,105 Hole transport layer 6,106 Light - emitting layer 7,107 Electron transport layer 8,108 Cathode 51,1051 First hole transport layer 52,1052 Second hole transport layer 71,1071 First electron transport layer 72,1072 Second electron transport layer 100 Organic Electroluminescent Devices

Claims

1. Triazine compound represented by formula X(1): 【Chemistry 1】 In formula X (1), A represents one of the bases selected from formulas X(A-1) and X(A-9): 【Chemistry 2】 B is a base represented by the formula X(B-1): 【Transformation 3】 Ar １ teeth, Phenyl group, 1-naphthalenyl group, 2-naphthalenyl group, 2-biphenylyl group, 3-biphenylyl group, 4-biphenylyl group, 2-(1-naphthalenyl)phenyl group, 3-(1-naphthalenyl)phenyl group, 4-(1-naphthalenyl)phenyl group, 2- (2-naphthalenyl)phenyl group, 3-(2-naphthalenyl)phenyl group, 4-(2-naphthalenyl)phenyl group, 4-phenylnaphthalen-1-yl group, 5-phenylnaphthalen-1-yl group, 6-phenylnaphthalen-2-yl group, 7-phenylnaphthalen-2-yl group, 2-phenantrenyl group, 3-phenantrenyl group, 9-phenantrenyl group, 9-anthracenyl group, p-terphenyl group, or 2-triphenylenyl group, or Represents a pyridyl group which may be substituted with a methyl group or a phenyl group. Ar ２ teeth, Phenyl group, 1-naphthalenyl group, 2-naphthalenyl group, 2-biphenylyl group, 3-biphenylyl group, 4-biphenylyl group, 2-(1-naphthalenyl)phenyl group, 3-(1-naphthalenyl)phenyl group, 4-(1-naphthalenyl)phenyl group, 2- (2-naphthalenyl)phenyl group, 3-(2-naphthalenyl)phenyl group, 4-(2-naphthalenyl)phenyl group, 4-phenylnaphthalen-1-yl group, 5-phenylnaphthalen-1-yl group, 6-phenylnaphthalen-2-yl group, 7-phenylnaphthalen-2-yl group, 2-phenantrenyl group, 3-phenantrenyl group, 9-phenantrenyl group, 9-anthracenyl group, p-terphenyl group, or 2-triphenylenyl group, or This represents a pyridyl group, which may be substituted with a methyl group or a phenyl group.

2. Ar １ However, it represents a phenyl group, 1-naphthalenyl group, 2-naphthalenyl group, 2-biphenylyl group, 3-biphenylyl group, or 4-biphenylyl group, which may be substituted with one or more groups selected from the group consisting of C1-C12 alkyl groups, C3-C20 cycloalkyl groups, cyano groups, diarylboryl groups, and phosphine oxide groups. Ar ２ The triazine compound according to claim 1, wherein the phenyl group, 1-naphthalenyl group, 2-naphthalenyl group, 2-biphenylyl group, 3-biphenylyl group, 4-biphenylyl group, 4-(1-naphthalenyl)phenyl group, or 9-phenantrenyl group may be substituted with one or more selected from the group consisting of C1-C12 alkyl groups, C3-C20 cycloalkyl groups, cyano groups, diarylboryl groups, and phosphine oxide groups.

3. A is a base represented by the formula X(A-1), B is a group represented by formula X(B-1), Ar １ However, it represents an unsubstituted phenyl group, 1-naphthalenyl group, 2-naphthalenyl group, 2-biphenylyl group, 3-biphenylyl group, or 4-biphenylyl group. Ar ２ The triazine compound according to claim 1 or 2, wherein the triazine represents an unsubstituted phenyl group, a 1-naphthalenyl group, a 2-naphthalenyl group, a 2-biphenylyl group, a 3-biphenylyl group, a 4-biphenylyl group, a 4-(1-naphthalenyl)phenyl group, or a 9-phenantrenyl group.

4. A material for an organic electroluminescent device comprising the triazine compound according to any one of claims 1 to 3.

5. An electron transport material for an organic electroluminescent device comprising the triazine compound according to any one of claims 1 to 3.

6. An organic electroluminescent device comprising the triazine compound according to any one of claims 1 to 3.

Images