Nitrogen containing condensed ring compound, fluorescent luminescent emitters, materials for organic electroluminescence devices, and organic electroluminescence devices

Abstract

The present invention relates to a nitrogen-containing condensed ring compound having a specific structure while satisfying specific conditions. Furthermore, the present invention relates to a fluorescent emitting agent comprising a nitrogen-containing condensed ring compound having a specific structure and used together with a phosphorescent complex. Additionally, the present invention relates to a material for an organic electroluminescent device comprising a nitrogen-containing condensed ring compound having a specific structure and a phosphorescent complex. Furthermore, the present invention relates to an organic electroluminescent device comprising these.

Description

Technology Field

[0001] This relates to a nitrogen-containing condensed ring compound, a fluorescent light-emitting agent, a material for an organic electroluminescent device, and an organic electroluminescent device. Background Technology

[0002] Recently, the development of materials and devices incorporating the TADF (Thermally Activated Delayed Fluorescence) mechanism is actively underway to improve the performance of organic electroluminescent devices. The TADF mechanism is the energy difference (ΔE) between the singlet level and the triplet level. ST It consists of a phenomenon in which a crossover between the triplet exciton and the singlet exciton occurs in compounds with a small amount. Details are described on pages 261-262 of Non-Patent Literature 1.

[0003] In the early stages of development, DA-type fluorescent materials equipped with donor and acceptor sites were used as compounds with TADF characteristics. However, these compounds have a wide full width at half maximum (FWHM) of the peak in their emission spectra, which may not be sufficient to meet the specifications required for wide color gamut devices. Therefore, narrowing the FWHM of compounds with TADF characteristics has been considered a challenge. Consequently, development has recently been promoted, including various studies such as using compounds with TADF characteristics as sensitizers or hosts.

[0004] Non-patent document 2 discloses a typical technique known as a hyperfluoroluminescence light-emitting device. This technique relates to a system that uses a compound having TADF characteristics as a sensitizer and performs energy transfer to a fluorescent dopant (luminescent dopant) via the sensitizer to produce light. However, in this system, the spectrum of the luminescent dopant becomes the emission spectrum of the device. For this reason, it became a problem that the emission spectrum of the device became a spectrum having multiple peaks of tetra t-Bu perylene (TBPe) used as the luminescent dopant.

[0005] Meanwhile, Patent Document 1 discloses a technology that employs a specific fluorescent compound (a nitrogen-containing condensed ring compound) having a narrow half-width emission spectrum to solve the above problem, and uses a compound having TADF characteristics as both a sensitizer and a host. As expected, this document can obtain luminescence with a narrow half-width emission spectrum, but it is presumed that the technology for practical application has not yet been completed, as there is no description of device lifespan, etc.

[0006] In addition, in the field of organic semiconductors, nitrogen-containing condensed ring compounds other than the compound having the skeletal structure disclosed in Patent Document 1 are also being considered. Such nitrogen-containing condensed ring compounds are disclosed in Patent Documents 2 to 4 and non-patent documents 3 and 4.

[0007] Non-patent document 2 discloses that a combination of a fluorescent material and a compound having TADF characteristics is effective in improving luminous efficiency, but it has not sufficiently improved the luminescence color purity of an organic electroluminescent device. This is due to the fact that the dopant used for blue light emission has multiple peaks.

[0008] By combining a specific fluorescent compound (nitrogen-containing condensed ring compound) disclosed in Patent Document 1 with a compound having TADF characteristics, high color purity is achieved due to the narrow half-width of the nitrogen-containing condensed ring compound used, but since the nitrogen-containing condensed ring compound itself does not have TADF characteristics, there remains a challenge regarding luminous efficiency. In addition, since there is no mention of device lifetime, it is presumed that there is also a challenge regarding long lifespan.

[0009] In addition, Patent Documents 2 and 3 disclose an organic semiconductor material and an organic electronic device, respectively, containing a nitrogen-containing condensed ring compound of a specific structure. However, Patent Documents 2 and 3 focus primarily on the electric field mobility of such nitrogen-containing condensed ring compounds, and the specifically manufactured device is an organic field-effect transistor. Therefore, Patent Documents 2 and 3 provide no description or indication regarding the use of such nitrogen-containing condensed ring compounds as light-emitting materials for organic electroluminescent devices or regarding the light emission characteristics of such nitrogen-containing condensed ring compounds. Furthermore, Patent Documents 2 and 3 provide no description or indication regarding the relationship between the structure of such nitrogen-containing condensed ring compounds and the color purity of the light emission.

[0010] Furthermore, Non-patent documents 3 and 4 each disclose the synthesis method, structure, and basic physical properties of nitrogen-containing condensed ring compounds of a specific structure, and disclose that such nitrogen-containing condensed ring compounds exhibit photoluminescence. However, Non-patent documents 3 and 4 provide no description or indication regarding the color purity of such nitrogen-containing condensed ring compounds. Additionally, Non-patent documents 3 and 4 provide no description or indication regarding combinations with other materials when such nitrogen-containing condensed ring compounds are used as light-emitting materials for organic electroluminescent devices. Moreover, Non-patent documents 3 and 4 provide no description or indication regarding the relationship between the structure of such nitrogen-containing condensed ring compounds and the color purity of the light emission.

[0011] Furthermore, Patent Document 4 discloses that an improvement in luminous efficiency is realized by an organic electroluminescent device comprising a nitrogen-containing condensed ring compound of a specific structure. It also discloses that the nitrogen-containing condensed ring compound is included in the emissive layer. Additionally, it discloses that the nitrogen-containing condensed ring compound is used as a dopant, and that a compound of a specific structure having an anthracene backbone is used as a host. However, Patent Document 4 provides no description or indication regarding the color purity of the nitrogen-containing condensed ring compound. Furthermore, it makes no mention of the TADF characteristics of the nitrogen-containing condensed ring compound itself, leaving a problem regarding luminous efficiency. Moreover, it discloses that the combined use of the nitrogen-containing condensed ring compound with a phosphorescent complex (phosphorescent material) is undesirable. Additionally, Patent Document 4 does not disclose the combined use of the nitrogen-containing condensed ring compound with specific compounds other than the host of the said structure. Furthermore, there is no description or indication regarding the relationship between the structure of the above-mentioned nitrogen-containing condensed ring compound and the luminescence color purity.

[0012] As such, although several conventional nitrogen-containing condensed ring compounds exhibiting a narrow half-width have been known, the coexistence of high color purity and high luminous efficiency in organic electroluminescent devices utilizing such characteristics has not been achieved. Furthermore, the relationship between the type of compound used in combination with the nitrogen-containing condensed ring compound and the luminescence purity of the organic electroluminescent device has not been sufficiently investigated. Prior art literature

[0013] Japanese Patent Publication No. 2020-053667, International Publication No. 2013 / 084805, International Publication No. 2013 / 084835, Japanese Patent Publication No. 2020-107742

[0014] Ahn, 「Device properties of organic semiconductors」, Kodansha, March 22, 2012 Hajime Nakanotani et al., 「High-efficiency organic light-emitting diodes with fluorescent emitters」, Nature Communications, 2014. 5. 4016 (DOI:10.1038 / ncomms5016)Claude Niebel et al., 「Dibenzo[2,3:5,6]pyrrolizino[1,7-bc]indolo[1,2,3-lm]carbazole:a new electron donor”, ​​New Journal of Chemistry, 2010, 34, 1243-1246Morgane Rivoal et al., 「Substituted dibenzo[2,3:5,6]-pyrrolizino[1,7-bc]Indolo[1,2,3-lm]carbazoles: a series of new electron donors」, Tetrahedron, 69, (2013), 3302-3307 The problem to be solved

[0015] One aspect is to provide a compound in which the peak wavelength of the emission spectrum is within the blue wavelength region, and which possesses high color purity while enabling high-efficiency emission.

[0016] Another aspect is to provide a fluorescent emitting agent containing the above compound.

[0017] Another aspect is to provide an organic electroluminescent material comprising the above-mentioned compound.

[0018] Another aspect is to provide a means to realize high-efficiency light emission while having high color purity, such that the peak wavelength of the emission spectrum in an organic electroluminescent device is within the blue wavelength region. means of solving the problem

[0019] At least one of the above problems can be solved by the following means.

[0020] A material for an organic electroluminescent device comprising a nitrogen-containing condensed ring compound having a structure represented by the following formula (1) and a phosphorescent complex:

[0021]

[0022] In the above equation (1),

[0023] R 1 to R 4 is an atom or group of (a) to (g) independently of each other, and

[0024] n1 to n4 are independently 0, 1, 2, 3, or 4, and

[0025] Not all of n1 through n4 are 0:

[0026] (a) Halogen atom,

[0027] (b) Cyanogi,

[0028] (c) Substituted or unsubstituted alkyl groups having 1 to 20 carbon atoms,

[0029] (d) Substituted or unsubstituted alkoxy groups having 1 to 20 carbon atoms,

[0030] (e) a substituted or unsubstituted aryl amino group having 6 to 20 carbon atoms,

[0031] (f) Substituted or unsubstituted monovalent aromatic hydrocarbon group,

[0032] (g) Substituted or unsubstituted monovalent heterocyclic group,

[0033] Here, if any one of n1 to n4 (one, multiple, or all) is 2 or more, each R 1 , each R 2 , each R 3 , or each R 4R1 and R2 may be the same or different from each other. That is, if n1 is 2 or more, each R1 may be the same or different from each other; if n2 is 2 or more, each R2 may be the same or different from each other; if n3 is 2 or more, each R3 may be the same or different from each other; and if n4 is 2 or more, each R4 may be the same or different from each other.

[0034] In addition, at least one of the above problems can be solved by the following means.

[0035] A fluorescent emitting agent used with a phosphorescent complex comprising a nitrogen-containing condensed ring compound having a structure represented by the above formula (1).

[0036] In addition, at least one of the above problems can be solved by the following means.

[0037] A nitrogen-containing condensed ring compound having a structure represented by the above formula (1) and satisfying all of the following conditions (i) to (iv):

[0038] <Condition (i)>

[0039] ΔE ST > ΔE ST2 + ΔE' TT

[0040] <Condition (ii)>

[0041] 0 eV < ΔE ST2 + ΔE' TT ≤ 1.0 eV

[0042] <Condition (iii)>

[0043] 0eV <ΔE' TT ≤ 0.15 eV

[0044] <Condition (iv)>

[0045] ΔE ST2 > 0 eV

[0046] Under the above conditions (i) to (iv),

[0047] ΔE ST(eV) represents the value of the difference between the lowest singlet excitation energy (eV) calculated for the S1 equilibrium structure and the lowest triplet excitation energy (eV) calculated for the T1 equilibrium structure;

[0048] ΔE ST2 (eV) represents the value of the difference between the lowest singlet excitation energy (eV) calculated for the S1 equilibrium structure and the second lowest triplet excitation energy (eV) calculated for the T2 equilibrium structure;

[0049] ΔE' TT (eV) represents the value of the difference between the second lowest triplet excitation energy (eV) calculated for a T2 equilibrium structure and the lowest triplet excitation energy (eV) calculated for a T2 equilibrium structure.

[0050] In addition, at least one of the above problems can be solved by the following means.

[0051] Nitrogen-containing condensed ring compounds having a structure represented by the following formula (1A) or the following formula (1B):

[0052]

[0053]

[0054] In the above equations (1A) and (1B),

[0055] A a To A d is a group derived independently from a benzene ring, a group derived from a carbazole ring, or a group represented by the following formula (1C), and

[0056]

[0057] R a to R dEach is independently a halogen atom, a cyano group, an unsubstituted alkyl group having 1 to 20 carbon atoms, an unsubstituted haloalkyl group having 1 to 20 carbon atoms, an unsubstituted alkoxy group having 1 to 20 carbon atoms, an unsubstituted alkyl amino group having 1 to 20 carbon atoms, an unsubstituted aryl amino group having 6 to 20 carbon atoms, a substituted or unsubstituted monovalent aromatic hydrocarbon group, or a substituted or unsubstituted monovalent aromatic heterocyclic group, and

[0058] R e and R f Each is independently a halogen atom, a cyano group, an unsubstituted alkyl group having 1 to 20 carbon atoms, an unsubstituted haloalkyl group having 1 to 20 carbon atoms, an unsubstituted alkoxy group having 1 to 20 carbon atoms, an unsubstituted haloalkoxy group having 1 to 20 carbon atoms, or an unsubstituted aryl amino group having 6 to 20 carbon atoms, and

[0059] A a To A d If each of them is a group derived from a benzene ring, na to nd are independently 0, 1, 2, 3, 4, or 5, and

[0060] A a To A d If each of them is derived from a carbazole ring, na to nd are independently 0, 1, 2, 3, 4, 5, 6, 7, or 8, and

[0061] A a To A d If each of them is represented by the above formula (1C), na to nd are independently 3, and

[0062] ne and nf are independently 0, 1, 2, 3, or 4, and

[0063] Here, when na is 2 or greater, each R a It may be the same or different,

[0064] If nb is 2 or greater, each Rb It may be the same or different,

[0065] If nc is 2 or greater, each R c It may be the same or different,

[0066] If nd is 2 or greater, each R d It may be the same or different,

[0067] If ne is 2 or greater, each R e It may be the same or different,

[0068] If nf is 2 or greater, each R f They may be identical or different from each other,

[0069] In the above equation (1C), * indicates the bonding position with an adjacent atom.

[0070] In addition, at least one of the above problems can be solved by the following means:

[0071] A nitrogen-containing condensed ring compound having a structure selected from the group consisting of the following formulas (2), (3), (7), (8) and (12) to (14):

[0072]

[0073] In the above equations (2) and (3),

[0074] R 5 to R 8 Each is independently a halogen atom, a cyano group, an unsubstituted alkyl group having 1 to 20 carbon atoms, an unsubstituted haloalkyl group having 1 to 20 carbon atoms, an unsubstituted alkoxy group having 1 to 20 carbon atoms, an unsubstituted alkyl amino group having 1 to 20 carbon atoms, or an unsubstituted aryl amino group having 6 to 20 carbon atoms, and

[0075] R 9 and R 10Each is independently a halogen atom, a cyano group, an unsubstituted alkyl group having 1 to 20 carbon atoms, an unsubstituted haloalkyl group having 1 to 20 carbon atoms, an unsubstituted alkoxy group having 1 to 20 carbon atoms, an unsubstituted haloalkoxy group having 1 to 20 carbon atoms, or an unsubstituted aryl amino group having 6 to 20 carbon atoms, and

[0076] n5 to n8 are independently 0, 1, 2, 3, 4, or 5, and

[0077] n9 and n10 are independently 0, 1, 2, 3, or 4, and

[0078] Here, if one of n5 to n10 is 2 or more, each R 5 , each R 6 , each R 7 , each R 8 , each R 9 Or each R10 may be the same or different from each other,

[0079] In the above formula (2), at least one of n5 to n8 is 3 or greater, or R 5 to R 8 At least one of them is an unsubstituted branched alkyl group having 4 to 15 carbon atoms, and

[0080] In the above equation (3), at least one of n5, n7, n9 and n10 is 3 or greater, or R 5 , R 7 , R 9 and R 10 At least one of them is an unsubstituted branched alkyl group having 4 to 15 carbon atoms.

[0081]

[0082]

[0083] In the above equations (7) and (8),

[0084] A 1 To A 4is independently an unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted monovalent aromatic hydrocarbon group, or a substituted or unsubstituted monovalent aromatic heterocyclic group, and

[0085] R 11 and R 12 Each is independently a halogen atom, a cyano group, an unsubstituted alkyl group having 1 to 20 carbon atoms, an unsubstituted haloalkyl group having 1 to 20 carbon atoms, an unsubstituted alkoxy group having 1 to 20 carbon atoms, an unsubstituted haloalkoxy group having 1 to 20 carbon atoms, or an unsubstituted aryl amino group having 6 to 20 carbon atoms, and

[0086] m1 to m4 are independently 0, 1, 2, 3, 4, or 5, and

[0087] n11 and n12 are independently 0, 1, 2, 3, or 4, and

[0088] Here, if m1 is 2 or greater, each A 1 It may be the same or different,

[0089] If m2 is 2 or greater, each A 2 It may be the same or different,

[0090] If m3 is 2 or greater, each A 3 It may be the same or different,

[0091] If m4 is 2 or greater, each A 4 It may be the same or different,

[0092] Also, if n11 is 2 or greater, each R 11 It may be the same or different,

[0093] If n12 is 2 or greater, each R 12 It may be the same or different,

[0094] In the above formula (7),

[0095] A 1 To A 4Not all of them are unsubstituted alkyl groups having 1 to 20 carbon atoms, and on the other hand, not all of m1 to m4 are 0,

[0096] In the above equation (8),

[0097] A 1 and A 3 Not all of them are unsubstituted alkyl groups having 1 to 20 carbon atoms, on the other hand, neither m1 nor m3 is 0;

[0098]

[0099]

[0100]

[0101] In the above formulas (12) to (14),

[0102] A 201 To A 204 is independently an unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted monovalent aromatic hydrocarbon group, or a substituted or unsubstituted monovalent aromatic heterocyclic group, and

[0103] R 201 and R 202 Each is independently a halogen atom, a cyano group, an unsubstituted alkyl group having 1 to 20 carbon atoms, an unsubstituted haloalkyl group having 1 to 20 carbon atoms, an unsubstituted alkoxy group having 1 to 20 carbon atoms, an unsubstituted alkyl amino group having 1 to 20 carbon atoms, an unsubstituted aryl amino group having 6 to 20 carbon atoms, a substituted or unsubstituted monovalent aromatic hydrocarbon group, or a substituted or unsubstituted monovalent aromatic heterocyclic group, and

[0104] R 203 and R 204Each is independently a halogen atom, a cyano group, an unsubstituted alkyl group having 1 to 20 carbon atoms, an unsubstituted haloalkyl group having 1 to 20 carbon atoms, an unsubstituted alkoxy group having 1 to 20 carbon atoms, an unsubstituted haloalkoxy group having 1 to 20 carbon atoms, or an unsubstituted aryl amino group having 6 to 20 carbon atoms, and

[0105] n201 and n202 are independently 0, 1, 2, 3, 4, or 5, and

[0106] n203 and n204 are independently 0, 1, 2, 3, or 4, and

[0107] Here, each A 201 may be the same or different, and each A 202 may be the same or different, and each A 203 may be the same or different, and each A 204 It may be the same or different,

[0108] 2 or more A 201 , 2 or more A 202 , 2 or more A 203 , 2 or more A 204 Each can form a ring, and

[0109] Also, if n201 is 2 or greater, each R 201 may be the same or different, and if n202 is 2 or greater, each R 202 may be the same or different, and if n203 is 2 or greater, each R 203 may be the same or different, and if n204 is 2 or greater, each R 204 It may be the same or different,

[0110] In the above equation (12), each A 201 , each A 202 , each A 203 , each A 204 Each is not entirely an unsubstituted alkyl group having 1 to 20 carbon atoms, and

[0111] In the above equation (13), each A 202 , each A 204 Each is not entirely an unsubstituted alkyl group having 1 to 20 carbon atoms, and

[0112] In the above equation (14), each A 201 , each A 203 Each of them is not an unsubstituted alkyl group having 1 to 20 carbon atoms. Effects of the invention

[0113] According to one embodiment, it is possible to provide a compound in which the peak wavelength of the emission spectrum is within the blue wavelength region, and while having high color purity, high-efficiency emission can be realized.

[0114] In addition, according to another form of work, it becomes possible to provide a fluorescent emitting agent containing the above compound.

[0115] According to another form of work, it is possible to provide a material for an organic electroluminescent device comprising the above compound.

[0116] Furthermore, according to another form of work, it is possible to provide a means to realize high-efficiency light emission while having high color purity, such that the peak wavelength of the emission spectrum in an organic electroluminescent device is within the blue wavelength region. Brief explanation of the drawing

[0117] FIG. 1 is a schematic cross-sectional view showing an organic electroluminescent device according to one embodiment. FIG. 2 is a schematic cross-sectional view showing an organic electroluminescent device according to another embodiment. FIG. 3 is a schematic cross-sectional view showing an organic electroluminescent device according to another embodiment. Figure 4 is an explanatory diagram that qualitatively explains the relationship between each energy. FIG. 5 is a graph of the redistribution energy (eV) calculated according to the FWHM-density functional method of luminescence in measured PL for known condensed ring compounds R1 to R3. FIG. 6 is a graph of the redistribution energy (eV) calculated by the FWHM-density functional method of fluorescence emission in measured PL for example compounds D1 to D8 according to one embodiment. FIG. 7 is a graph of emission wavelengths calculated by the fluorescence wavelength-density functional method in the measured PL for example compounds D1 to D8 according to one embodiment. Specific details for implementing the invention

[0118] Embodiments of the present invention are described below. Additionally, the present invention is not limited to the following embodiments. Furthermore, unless specifically stated otherwise, operations and measurements of physical properties, etc. are performed under conditions of room temperature (20°C or higher and 25°C or lower) and relative humidity of 40% RH or higher and 50% RH or lower.

[0119] In this specification, "X and Y are each independent" means that X and Y may be the same or different.

[0120] In addition, in this specification, "group derived from a ring" refers to a group in which a hydrogen atom directly bonded to a ring-forming atom of a ring structure has its valence reduced by an amount equal to its valence. Here, a ring-forming atom refers to an atom that directly forms a ring structure. For example, in the case of a benzene ring, the ring-forming atom is a carbon atom, and hydrogen atoms are not included in the ring-forming atom.

[0121] <Nitrogen-containing condensed ring compounds>

[0122] The present invention relates to a nitrogen-containing condensed ring compound having a structure represented by the following formula (1):

[0123]

[0124] In the above equation (1),

[0125] R1 to R 4 is an atom or group of (a) to (g) independently of each other, and

[0126] n1 to n4 are independently 0, 1, 2, 3, or 4, and

[0127] Not all of n1 to n4 are 0:

[0128] (a) Halogen atom,

[0129] (b) Cyanogi,

[0130] (c) Substituted or unsubstituted alkyl groups having 1 to 20 carbon atoms,

[0131] (d) Substituted or unsubstituted alkoxy groups having 1 to 20 carbon atoms,

[0132] (e) a substituted or unsubstituted aryl amino group having 6 to 20 carbon atoms,

[0133] (f) Substituted or unsubstituted monovalent aromatic hydrocarbon group,

[0134] (g) Substituted or unsubstituted monovalent heterocyclic group,

[0135] Here, if any one of n1 to n4 (one, multiple, or all) is 2 or more, each R 1 , each R 2 , each R 3 , or each R 4 They can be identical or different from each other. That is, when n1 is 2 or greater, each R 1 They may be identical or different from each other, and for cases where n2 is 2 or greater, each R 2 may be identical or different from each other, and for cases where n3 is 2 or greater, each R 3 They may be identical or different from each other, and for cases where n4 is 2 or greater, each R 4 They may be the same or different from each other.

[0136] Hereinafter, the nitrogen-containing condensed ring compound according to the present invention will also be referred to simply as the "nitrogen-containing condensed ring compound."

[0137] The inventors estimate the mechanism by which the problem is solved by the above configuration as follows.

[0138] The emission wavelength of a luminescent material changes not only due to its skeletal structure but also due to the type and bonding position of the substituents. As a result of introducing specific substituents at specific positions in the aforementioned nitrogen-containing condensed ring compound, the peak wavelength of the emission spectrum is extended to within the blue wavelength region. Consequently, it satisfies sufficient characteristics as a luminescent material for organic electroluminescent devices, particularly as a blue luminescent material. In particular, the introduction of substituents suppresses intermolecular aggregation and improves the solubility of the molecules themselves, thereby enhancing the degree of purification and consequently improving the color purity of the emission. Furthermore, in general luminescent materials, increasing the amount added leads to intermolecular aggregation, resulting in emission caused by the aggregation state, which widens the emission spectrum and tends to lower color purity. However, the aforementioned nitrogen-containing condensed ring compound is resistant to intermolecular aggregation; therefore, even when the amount added is increased, there is no decrease in color purity, and high-color-purity emission can be realized. Additionally, this result allows for improved luminescence efficiency. In addition, when the above-mentioned nitrogen-containing condensed ring compound and phosphorescent complex are used in combination, a significantly extended lifespan of the organic electroluminescent device can be realized.

[0139] In addition, since the above mechanism is based on conjecture, its correctness or incorrectness does not affect the technical scope of the present invention. Likewise, regarding other conjectural matters in this specification, their correctness or incorrectness does not affect the technical scope of the present invention.

[0140] As such, one embodiment of the present invention relates to a nitrogen-containing condensed ring compound represented by the above formula (1). Another embodiment of the present invention relates to a fluorescent emitting agent used in combination with a phosphorescent complex, comprising a nitrogen-containing condensed ring compound having a structure represented by the above formula (1). And another embodiment of the present invention relates to a material for an organic electroluminescent device comprising a nitrogen-containing condensed ring compound having a structure represented by the following formula (1) and a phosphorescent complex described below.

[0141] The following describes a nitrogen-containing condensed ring compound according to one embodiment of the present invention, a nitrogen-containing condensed ring compound included in a fluorescent light-emitting agent according to one embodiment of the present invention, and a nitrogen-containing condensed ring compound included in a material for an organic electroluminescent device according to one embodiment of the present invention.

[0142] In the above formula (1), the atoms or groups of (a) to (g) may be the atoms or groups of (a) to (d), (f), or (g).

[0143] In the above formula (1), if the groups of (c) to (g) are substituted, the substituents substituting these groups are not particularly limited. However, the substituents substituting the groups of (c) and (d) in the above formula (1) may be at least one substituent selected independently from the group consisting of a halogen atom, a cyano group, an unsubstituted alkoxy group having 1 to 20 carbon atoms, an unsubstituted alkyl amino group having 1 to 20 carbon atoms, an unsubstituted aryl amino group having 6 to 20 carbon atoms, and a substituted or unsubstituted monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms. Here, the substituted or unsubstituted monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms may be an unsubstituted monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms.

[0144] In addition, the substituent that substitutes the group of (e) in the above formula (1) may be at least one substituent selected from the group consisting of a halogen atom, a cyano group, an unsubstituted alkyl group with 1 to 20 carbon atoms, an unsubstituted haloalkyl group with 1 to 20 carbon atoms, an unsubstituted alkoxy group with 1 to 20 carbon atoms, an unsubstituted alkyl amino group with 1 to 20 carbon atoms, and an unsubstituted aryl amino group with 6 to 20 carbon atoms. And in the above formula (1), the substituent substituting the group of (f) may be at least one substituent selected from the group consisting of a halogen atom, a cyano group, a substituted or unsubstituted alkyl group with 1 to 20 carbon atoms, an unsubstituted haloalkyl group with 1 to 20 carbon atoms, an unsubstituted alkoxy group with 1 to 20 carbon atoms, an unsubstituted alkyl amino group with 1 to 20 carbon atoms, an unsubstituted aryl amino group with 6 to 20 carbon atoms, and an unsubstituted monovalent heterocyclic group with 3 to 30 cyclic atoms. Here, the substituent of the substituted alkyl group with 1 to 20 carbon atoms is not particularly limited, but may be a monovalent aromatic hydrocarbon group with 6 to 30 carbon atoms substituted or unsubstituted with an unsubstituted alkyl group with 1 to 20 carbon atoms, or a halogen atom. In addition, in the above formula (1), the substituent substituting the group of (f) may be at least one substituent selected from the group consisting of a halogen atom, a cyano group, an unsubstituted alkyl group with 1 to 20 carbon atoms, an unsubstituted haloalkyl group with 1 to 20 carbon atoms, an unsubstituted alkoxy group with 1 to 20 carbon atoms, an unsubstituted alkyl amino group with 1 to 20 carbon atoms, an unsubstituted aryl amino group with 6 to 20 carbon atoms, and an unsubstituted heterocyclic group with 3 to 30 valence atoms.In addition, the substituent that substitutes the group of (g) in the above formula (1) may be at least one substituent selected from the group consisting of a halogen atom, a cyano group, an unsubstituted alkyl group with 1 to 20 carbon atoms, an unsubstituted haloalkyl group with 1 to 20 carbon atoms, an unsubstituted alkoxy group with 1 to 20 carbon atoms, an unsubstituted alkyl amino group with 1 to 20 carbon atoms, an unsubstituted aryl amino group with 6 to 20 carbon atoms, and an unsubstituted monovalent aromatic hydrocarbon group with 6 to 30 carbon atoms.

[0145] In the above equation (1), n1, n2, n3, or n4 being 0 means that the R corresponding to them 1 , R 2 , R 3 or R 4 It means that does not exist. In other words, in the above equation (1), n1 being 0 means R 1 This means that it does not exist, and n2 being 0 is R 2 It means that does not exist, and n3 being 0 is R 3 This means that it does not exist, and n4 being 0 is R 4 This means that R does not exist. That is, in the above equation (1), R 1 , R 2 , R 3 or R 4 The cyclic carbon atom described to be bonded is unsubstituted, and indicates that a hydrogen atom is bonded to the cyclic carbon atom.

[0146] n1 to n4 can be 0 or 1 independently of each other.

[0147] The halogen atom in (a) above is not particularly limited, but examples include fluorine atoms, chlorine atoms, bromine atoms, or iodine atoms. Among these, it may be a fluorine atom from the perspective of device lifespan.

[0148] The alkyl group having 1 to 20 carbon atoms in (c) above is not particularly limited and may be straight-chain, branched, or cyclic. Among these, it may be branched from the perspective of device lifespan and emission color purity. The number of carbon atoms in the alkyl group may be 2 or more, or 3 or more, or 4 or more from the perspective of solubility and emission color purity. In addition, the number of carbon atoms in the alkyl group may be 10 or less, or 8 or less, or 6 or less from the perspective of device lifespan. The number of carbon atoms in the alkyl group may be 4 from this perspective. Specific examples of alkyl groups are not particularly limited, but include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, s-butyl group (sec-butyl group), t-butyl group (tert-butyl group), i-butyl group, 2-ethylbutyl group, 3,3-dimethylbutyl group, n-pentyl group, i-pentyl group, neopentyl group, t-pentyl group, cyclopentyl group, 1-methylpentyl group, 3-methylpentyl group, 2-ethylpentyl group, 4-methyl-2-pentyl group, n-hexyl group, 1-methylhexyl group, 2-ethylhexyl group, 2-butylhexyl group, cyclohexyl group, 4-methylcyclohexyl group, 4-t-butylcyclohexyl group, n-heptyl group, 1-methylpeptyl group, 2,2-dimethylheptyl group, 2-ethyl heptyl group, 2-butyl heptyl group, n-octyl group, t-octyl group, 2-ethyl octyl group, 2-butyl octyl group, 2-hexyl octyl group, 3,7-dimethyl octyl group, cyclooctyl group, n-nonyl group, n-decyl group, adamantyl group, 2-ethyl decyl group, 2-butyl decyl group, 2-hexyl decyl group, 2-octyl decyl group, n-undecyl group, n-dodecyl group, 2-ethyl dodecyl group, 2-butyl dodecyl group, 2-hexyl dodecyl group, 2-octyl decyl group, n-tridecyl group, n-tetradecyl group, n-pentadecyl group, n-hexadecyl group, 2-ethyl hexadecyl group, 2-butyl hexadecyl group, n-heptadecyl group, Examples include n-octadecyl groups, n-nonadecyl groups, or n-icosyl groups. Among these, it may be a branched alkyl group, an isopropyl group, or a tert-butyl group, or a tert-butyl group.

[0149] Additionally, “substituted alkyl group with 1 to 20 carbon atoms” refers to a group in which an unsubstituted alkyl group with 1 to 20 carbon atoms is substituted by a substituent. Therefore, the number of carbon atoms in the substituted alkyl group may exceed 20.

[0150] The alkoxy group having 1 to 20 carbon atoms in (d) above is not particularly limited, and the alkoxy group may be linear, branched, or cyclic. Among these, it may be linear from the perspective of device lifetime. The number of carbon atoms in the alkoxy group may be 1 to 10 from the perspective of device lifetime. Also, from the same perspective, the number of carbon atoms in the alkoxy group may be 1 to 8, 1 to 6, or 1. The alkyl group constituting the alkoxy group is not particularly limited, but examples include those described in the description of the alkyl group above. Specific examples of the alkoxy group are not particularly limited, but examples include methoxy groups, ethoxy groups, n-propoxy groups, isopropoxy groups, butoxy groups, pentyl oxy groups, hexyl oxy groups, octyl oxy groups, nonyl oxy groups, or decyl oxy groups. Among these, it may be a methoxy group.

[0151] Additionally, "substituted alkoxy groups with 1 to 20 carbon atoms" refers to a group in which an unsubstituted alkoxy group with 1 to 20 carbon atoms is substituted by a substituent. Therefore, the number of carbon atoms of the substituted alkoxy group may exceed 20.

[0152] The nitrogen atom of the aryl amino group having 6 to 20 carbon atoms in (e) above is R in the above formula (1). 1 , R 2 , R 3 or R 4It is bonded by a single bond with a cyclic carbon atom described so that it can be bonded. Additionally, even if a group containing a nitrogen atom is described in this specification, if the nitrogen atom is a cyclic atom of a heterocyclic group, the group should be treated as a heterocyclic group described below rather than an aryl amino group. The aryl group constituting the aryl amino group is not particularly limited, but examples include a group having 6 or more and 20 or fewer carbon atoms among the monovalent aromatic hydrocarbon groups described below. The aryl amino group is not particularly limited and may be a monoaryl amino group or a diaryl amino group. Specific examples of aryl amino groups are not particularly limited, but examples include an N-phenylamino group, an N-biphenylamino group, an N-terphenylamino group, an N,N-diphenylamino group, or an N-biphenyl-N-phenylamino group.

[0153] Additionally, “substituted aryl amino group with 6 to 20 carbon atoms” refers to a group in which an unsubstituted aryl amino group with 6 to 20 carbon atoms is substituted by a substituent. Therefore, the number of carbon atoms in the substituted aryl amino group may exceed 20.

[0154] The monovalent aromatic hydrocarbon group of (f) above represents a group derived from one or more aromatic hydrocarbon groups. In this specification, an aromatic hydrocarbon group represents a hydrocarbon group that is partially or wholly aromatic.

[0155] When a monovalent aromatic hydrocarbon group contains two or more aromatic hydrocarbon rings, these rings may be connected to each other by single bonds or condensed. In addition, when a monovalent aromatic hydrocarbon group contains two or more aromatic hydrocarbon rings, one atom may serve as a ring-forming atom of any of these rings.

[0156] The number of carbon atoms in the monovalent aromatic hydrocarbon group is not particularly limited, but may be 6 or more and 30 or less from the perspective of luminescence color purity. Also, the number of carbon atoms in the monovalent aromatic hydrocarbon group may be 6 or more and 20 or less, or 6 or more and 12 or less, or 6.

[0157] Specific examples of monovalent aromatic hydrocarbon groups are not particularly limited, but include phenyl groups, mesethyl groups, t-butylphenyl groups, bis(t-butyl)phenyl groups, biphenyl groups, terphenyl groups, naphthyl groups, fluorenyl groups, anthracenyl groups, terphenyl groups, quarterphenyl groups, quinquephenyl groups, sexyphenyl groups, triphenylenyl groups, pyrenyl groups, benzofluorenyl groups, chrysenyl groups, or groups composed of combinations thereof.

[0158] Additionally, "substituted monovalent aromatic hydrocarbon group" refers to a group in which an unsubstituted monovalent aromatic hydrocarbon group is substituted by a substituent. Therefore, if the monovalent aromatic hydrocarbon group has a carbon number of 30 or fewer, for example, or is below a specific upper limit value, the carbon number of the substituted monovalent aromatic hydrocarbon group may exceed the above upper limit value.

[0159] The monovalent heterocyclic group of (g) above refers to a group derived from one or more heterocyclic groups. The monovalent heterocyclic group is not particularly limited and may be a monovalent aromatic heterocyclic group or a monovalent non-aromatic heterocyclic group. Among these, it may be a monovalent aromatic heterocyclic group in terms of luminescence color purity.

[0160] A monovalent aromatic heterocyclic group refers to a group derived from a heterocyclic group having one or more aromatic properties. In this specification, an aromatic heterocyclic group refers to a heterocyclic group having partially or wholly aromatic properties. When an aromatic heterocyclic group has partially aromatic properties, the aromatic properties may originate from the heterocyclic portion of the ring or from the hydrocarbon portion of the ring. The aromatic heterocyclic group is not particularly limited, but examples include a ring having one or more heterocyclic atoms (e.g., nitrogen atom (N), oxygen atom (O), phosphorus atom (P), sulfur atom (S), silicon atom (Si)) as cyclic atoms, and the remaining cyclic atoms being carbon atoms (C). In addition, there are cases where atoms constituting the ring structure are bonded to atoms outside the ring through double bonds, such as when carbon atoms constituting the ring structure form a ketone group (C=O group), a thioketone group (C=S group), or a C=NH group, or when sulfur atoms constituting the ring structure form a sulfinyl group (S=O group) or a sulfonyl group (S(=O)=O group). In this specification, the atom outside the ring that forms a double bond with the atom constituting the ring structure is considered to be part of an aromatic heterocyclic ring. Furthermore, when the atom outside the ring that forms the double bond is bonded to a hydrogen atom through a single bond, the hydrogen atom is also considered to be part of an aromatic heterocyclic ring.Specific examples of aromatic heterocyclic rings are not particularly limited, but include pyridine rings, pyrazine rings, pyridazine rings, pyrimidine rings, triazine rings, quinoline rings, isoquinoline rings, quinoxaline rings, quinazolin rings, naphthylidine rings, acridine rings, phenazine rings, benzoquinoline rings, benzisoquinoline rings, phenanthridine rings, phenanthroline rings, benzoquinone rings, coumarine rings, anthraquinone rings, fluorenone rings, furan rings, thiophene rings, benzofuran rings, benzothiophene rings, dibenzofuran rings, dibenzothiophene rings, pyrrole rings, indole rings, carbazole rings, indolecarbazole rings, imidazole rings, benzimidazole rings, pyrazol rings, indazole rings, oxazole rings, isooxazole rings, benzoxazole rings, Examples include benzioxazole, thiazole, isothiazol, benzothiazol, benzioisothiazole, imidazolinone, benzimidazolinone, imidazolpyridine, imidazolpyrimidine, imidazolphenanthridine, benzimidazolephenanthridine, azadibenzofuran, azacarbazole, azadibenzothiophen, diazadibenzofuran, diazcarbazole, diazadibenzothiophen, xanthon, or thioxanthon.

[0161] When a monovalent aromatic heterocyclic group contains two or more aromatic heterocyclic rings, these rings may be connected to each other by single bonds or condensed. Additionally, when a monovalent aromatic heterocyclic group contains two or more aromatic heterocyclic rings, one atom may serve as the ring-forming atom of any of these rings.

[0162] The number of cyclic atoms of a monovalent aromatic heterocyclic group (the sum of the number of cyclic carbon atoms and the number of cyclic heterocyclic atoms) is not particularly limited, but may be 3 or more and 30 or less in terms of the peak wavelength of the emission spectrum and the color purity of the emission. In addition, the number of cyclic atoms of a monovalent aromatic heterocyclic group may be 5 or more and 20 or less in terms of the same, or 6 or more and 14 or less. The number of cyclic heterocyclic atoms of a monovalent aromatic heterocyclic group is not particularly limited, but may be 1 or more and 10 or less in terms of the peak wavelength of the emission spectrum and the color purity of the emission. In addition, the number of cyclic heterocyclic atoms of a monovalent aromatic heterocyclic group may be 1 or more and 5 or less in terms of the same, or 1 or more and 3 or less. Furthermore, as previously stated, a cyclic atom refers to an atom that directly forms a ring structure. From this, if there is an atom outside the ring that forms a double bond with an atom constituting the ring structure, said atom is not included in the ring-forming atom.

[0163] Specific examples of monovalent aromatic heterocyclic groups are not particularly limited, but include thienyl group, furanyl group, pyrrolyl group, imidazoleyl group, thiazoleyl group, oxazoleyl group, oxadiazoleyl group, triazoleyl group, pyridyl group, bipyridyl group, pyrimidyl group, triazinyl group, acrridinyl group, pyridazinyl group, pyrazinyl group, quinolinyl group, quinazolinyl group, quinoxalinyl group, phenoxazinyl group, phthalazinyl group, pyridopyrimidinyl group, pyridopyrazinyl group, pyrazinopyrazinyl group, isoquinolinyl group, indole group, carbazoleyl group, benzoxazoleyl group, benzimidazoleyl group, benzothiazoleyl group, benzocarbazoleyl group, benzothiophenyl group, dibenzothiophenyl group, Examples include thienothienyl groups, benzofuranyl groups, phenantolinyl groups, thiazole groups, isooxazole groups, oxadiazole groups, thiadiazole groups, phenothiazinyl groups, dibenzosirol groups, dibenzofuranyl groups, or xanthonyl groups. Among these, it may be a triazinyl group, a carbazole group, a benzoxazole group, or a xanthonyl group.

[0164] In addition, a non-aromatic heterocyclic group refers to a group derived from one or more non-aromatic heterocyclic groups. In this specification, a non-aromatic heterocyclic group refers to a heterocyclic group that does not have aromaticity in part or in whole. A non-aromatic heterocyclic group is not particularly limited, but may be, for example, a ring having one or more heterocyclic atoms (e.g., nitrogen atom (N), oxygen atom (O), phosphorus atom (P), sulfur atom (S), silicon atom (Si)) as cyclic atoms, and the remaining cyclic atoms being carbon atoms (C). The heterocyclic atoms may be nitrogen atoms (N) and oxygen atoms (O) in terms of the peak wavelength of the emission spectrum and the color purity of the emission. Additionally, there are cases where atoms constituting the ring structure are bonded to atoms outside the ring through double bonds, such as when carbon atoms constituting the ring structure form a ketone group (C=O group), a thioketone group (C=S group), or a C=NH group, or when sulfur atoms constituting the ring structure form a sulfinyl group (S=O group) or a sulfonyl group (S(=O)=O group). In this case, the atoms outside the ring that form a double bond with the atoms constituting the ring structure are considered as part of a non-aromatic heterocyclic ring. Furthermore, when the atoms outside the ring that form the double bond are bonded to a hydrogen atom through a single bond, the hydrogen atom is also considered as part of a non-aromatic heterocyclic ring. Specific examples of non-aromatic heterocyclic rings are not particularly limited, but include pyrrolidine rings, tetrahydrofuran rings, tetrahydrothiophene rings, piperidine rings, tetrahydropyran rings, tetrahydrothiopyran rings, dioxane rings, morpholine rings, or dioxolein rings.

[0165] When a monovalent non-aromatic heterocyclic group contains two or more non-aromatic heterocyclic groups, these rings may be connected to each other by single bonds or condensed. Also, when a monovalent non-aromatic heterocyclic group contains two or more non-aromatic heterocyclic groups, one atom may serve as the ring-forming atom of any of these rings.

[0166] The number of cyclic atoms of a monovalent non-aromatic heterocyclic group (the sum of the number of cyclic carbon atoms and the number of cyclic heterocyclic atoms) is not particularly limited, but may be 3 or more and 30 or less in terms of the peak wavelength of the emission spectrum and the color purity of the emission. In addition, the number of cyclic atoms of a monovalent non-aromatic heterocyclic group may be 5 or more and 20 or less in terms of the same, or 6 or more and 14 or less. The number of cyclic heterocyclic atoms of a monovalent non-aromatic heterocyclic group is not particularly limited, but may be 1 or more and 10 or less in terms of the peak wavelength of the emission spectrum and the color purity of the emission. In addition, the number of cyclic heterocyclic atoms of a monovalent non-aromatic heterocyclic group may be 1 or more and 5 or less in terms of the same, or 1 or more and 3 or less. Furthermore, as previously stated, a cyclic atom refers to an atom that directly forms a ring structure. From this, if there is an atom outside the ring that forms a double bond with an atom constituting the ring structure, said atom is not included in the ring-forming atom.

[0167] Specific examples of monovalent non-aromatic heterocyclic groups are not particularly limited, but include pyrrolidinyl groups, tetrahydrofuranyl groups, tetrahydrothienyl groups, pyridinyl groups, tetrahydropyranyl groups, tetrahydrothiopyranyl groups, dioxanyl groups, morphonyl groups, or dioxoranyl groups.

[0168] Additionally, "substituted monovalent heterogroup" refers to a group in which an unsubstituted monovalent heterogroup is substituted by a substituent. Therefore, when the number of ring-forming atoms of a monovalent heterogroup is, for example, 30 or less, or lower than a specific upper limit, and the substituent forms a ring structure, the number of ring-forming atoms of the substituted monovalent heterogroup may exceed the upper limit.

[0169] The groups of (c) to (g) above may be substituted groups. The substituents that substitute the groups of (c) to (g) above—a halogen atom, a cyano group, an unsubstituted alkyl group having 1 to 20 carbon atoms, an unsubstituted alkoxy group having 1 to 20 carbon atoms, and an unsubstituted aryl amino group having 6 to 20 carbon atoms—are each the same as the unsubstituted groups in the descriptions of (a), (c), (d), and (e). Among these, they may be a halogen atom or an unsubstituted alkyl group having 1 to 20 carbon atoms. They may also be a fluorine atom or an unsubstituted straight-chain or branched alkyl group having 1 to 20 carbon atoms. Alternatively, they may be a fluorine atom, a methyl group, an ethyl group, an isopropyl group, or a tert-butyl group.

[0170] The unsubstituted alkyl group having 1 to 20 carbon atoms, which is a substituent for the group of (f) above, is the same as the unsubstituted group described in (c) above. Among these, it may be a straight-chain or branched alkyl group having 1 to 20 carbon atoms. It may also be a methyl group, an ethyl group, an isopropyl group, or a tert-butyl group.

[0171] In addition, the unsubstituted alkyl amino group having 1 to 20 carbon atoms, which is a substituent for the groups of (c) to (g) above, is bonded by a single bond to the nitrogen atom of several atoms constituting the unsubstituted groups of (c) to (g) above in Formula (1). The alkyl group constituting the alkyl amino group is not particularly limited, but is, for example, as described in (c). The alkyl amino group is not particularly limited and may be a monoalkyl amino group or a dialkyl amino group. Specific examples of alkyl amino groups are not particularly limited, but include N-methyl amino group, N-ethyl amino group, N-propyl amino group, N-isopropyl amino group, N-butyl amino group, N-isobutyl amino group, N-sec-butyl amino group, N-tert-butyl amino group, N-pentyl amino group, N-hexyl amino group, N,N-dimethyl amino group, N-methyl-N-ethyl amino group, N,N-diethyl amino group, N,N-dipropyl amino group, N,N-diisopropyl amino group, N,N-dibutyl amino group, N,N-diisobutyl amino group, N,N-dipentyl amino group, or N,N-dihexylamino group.

[0172] An unsubstituted haloalkyl group having 1 to 20 carbon atoms, which is a substituent for the groups of (e) to (g) above, may be used, wherein at least one hydrogen atom of the alkyl group described in (c) above is substituted by the halogen atom described in (a). The halogen atom may be a fluorine atom for the sake of device lifespan. Specific examples of haloalkyl groups may include, for instance, trifluoromethyl groups, trichloromethyl groups, tribromomethyl groups, or triiodomethyl groups. Among these, it may be a fluorinated alkyl group and may be a trifluoromethyl group.

[0173] The monovalent heterocyclic group having 3 to 30 unsubstituted cyclic atoms, which is a substituent for the group of (f) above, is the same as the unsubstituted group described in (g) above, except that the range of the number of cyclic atoms is limited. Among these, it may be a monovalent heterocyclic group containing oxygen or nitrogen atoms as heteroatoms, and specifically, it may be a dibenzofuranyl group, a carbazole group, or a benzoxazole group. In addition, for example, it may be a dibenzofuranyl group or a carbazole group.

[0174] The unsubstituted monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms, which is a substituent for the groups of (c), (d), and (g), is the same as the unsubstituted group described in (f), except that the range of the number of carbon atoms is limited. Among these, it may be a group derived from a benzene ring.

[0175] In the case where the group of (c) to (g) above is a substituted group, the substituent may be a group that has been substituted with a new substituent. The new substituent is not particularly limited, but, for example, may be one of the substituents listed in the case where the group of (c) to (g) above is a substituted group, or a group in which such a group is further substituted according to this basis.

[0176] In the substituted monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms that substitutes the groups of (c) and (d), the monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms is the same as the unsubstituted group described in (g), except that the range of the number of carbon atoms is limited. Among these, it may be a group derived from a benzene ring. Additionally, the substituent that substitutes the monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms is not particularly limited, but may be an unsubstituted alkyl group having 1 to 20 carbon atoms. The unsubstituted alkyl group having 1 to 20 carbon atoms is the same as the unsubstituted group described in (c). Among these, it may be an unsubstituted straight-chain or branched alkyl group having 1 to 20 carbon atoms. Additionally, it may be a methyl group, an ethyl group, an isopropyl group, or a tert-butyl group.

[0177] In the substituted monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms that substitutes the groups of (c) and (d) above, the monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms is the same as the unsubstituted group described in (g) above, except that the range of the number of carbon atoms is limited. Among these, it may be a group derived from a benzene ring. In addition, the substituent that substitutes the monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms is not particularly limited but may be an unsubstituted alkyl group having 1 to 20 carbon atoms. The unsubstituted alkyl group having 1 to 20 carbon atoms is the same as the unsubstituted group described in (c) above. Among these, it may be an unsubstituted straight-chain or branched alkyl group having 1 to 20 carbon atoms. In addition, it may be a methyl group, an ethyl group, an isopropyl group, or a tert-butyl group.

[0178] In the substituted alkyl group having 1 to 20 carbon atoms that substitutes the group of (f) above, the alkyl group having 1 to 20 carbon atoms is the same as the unsubstituted group described in (c) above. Among these, it may be a straight-chain or branched alkyl group having 1 to 20 carbon atoms. It may also be a methyl group, an ethyl group, an isopropyl group, or a tert-butyl group. Furthermore, as a substituent for the alkyl group having 1 to 20 carbon atoms, it is not particularly limited but may be a monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms that is substituted with or unsubstituted with an unsubstituted alkyl group having 1 to 20 carbon atoms. Here, the unsubstituted alkyl group having 1 to 20 carbon atoms that substitutes the monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms is the same as the unsubstituted group described in (c) above. Among these, it may be an unsubstituted straight-chain or branched alkyl group having 1 to 20 carbon atoms. It may also be a methyl group, an ethyl group, an isopropyl group, or a tert-butyl group.

[0179] In the above equation (1), R 1 to R 4 At least one of the atoms or groups represented by is R in a core portion (hereinafter simply referred to as the core portion) formed by a group derived from a ring represented by the following formula (1-1). 1 to R 4 The atom or group represented by can be bonded to at least one cyclic carbon atom selected from the group consisting of a cyclic carbon atom adjacent to a cyclic carbon atom bonded to a nitrogen atom, a cyclic carbon atom adjacent to said cyclic carbon atom, and a cyclic carbon atom adjacent to said cyclic carbon atom, of the portion of a group derived from a benzene ring to which the atom or group can be bonded. In the above formula (1), the substituents that can be bonded to such cyclic carbon atoms are not particularly limited, but examples include a terphenyl group, a phenyl group substituted with two or more alkyl groups having 1 to 4 carbon atoms, etc. Also, examples include an m-terphenyl group, a 2,6-di-tert-butylphenyl group, etc.

[0180]

[0181] In the nitrogen-containing condensed ring compound according to the present invention, the structure represented by the above formula (1) may be a structure represented by the following formula (1A) or the following formula (1B) from the perspective of the peak wavelength of the emission spectrum and the color purity of the emission. That is, one embodiment of the present invention relates to a nitrogen-containing condensed ring compound having a structure represented by the following formula (1A) or the following formula (1B). Furthermore, as one embodiment of a material for an organic electroluminescent device described below, an organic electroluminescent device material may be provided in which the structure represented by the above formula (1) of the nitrogen-containing condensed ring compound is a structure represented by the following formula (1A) or the following formula (1B). Furthermore, as one embodiment of a fluorescent emitting agent described below, a fluorescent emitting agent may be provided in which the structure represented by the above formula (1) of the nitrogen-containing condensed ring compound is a structure represented by the following formula (1A) or the following formula (1B).

[0182]

[0183]

[0184] In the above equations (1A) and (1B),

[0185] A a To A d is a group derived independently from a benzene ring, a group derived from a carbazole ring, or a group represented by the following formula (1C), and

[0186]

[0187] R a to R dEach is independently a halogen atom, a cyano group, an unsubstituted alkyl group having 1 to 20 carbon atoms, an unsubstituted haloalkyl group having 1 to 20 carbon atoms, an unsubstituted alkoxy group having 1 to 20 carbon atoms, an unsubstituted alkyl amino group having 1 to 20 carbon atoms, an unsubstituted aryl amino group having 6 to 20 carbon atoms, a substituted or unsubstituted monovalent aromatic hydrocarbon group, or a substituted or unsubstituted monovalent aromatic heterocyclic group, and

[0188] R e and R f Each is independently a halogen atom, a cyano group, an unsubstituted alkyl group having 1 to 20 carbon atoms, an unsubstituted haloalkyl group having 1 to 20 carbon atoms, an unsubstituted alkoxy group having 1 to 20 carbon atoms, an unsubstituted haloalkoxy group having 1 to 20 carbon atoms, or an unsubstituted aryl amino group having 6 to 20 carbon atoms, and

[0189] A a To A d If each of them is a group derived from a benzene ring, na to nd are independently 0, 1, 2, 3, 4, or 5, and

[0190] A a To A d If each of them is derived from a carbazole ring, na to nd are independently 0, 1, 2, 3, 4, 5, 6, 7, or 8, and

[0191] A a To A d If each of them is represented by the above formula (1C), na to nd are independently 3, and

[0192] ne and nf are independently 0, 1, 2, 3, or 4, and

[0193] Here, if na is 2 or greater, each R a may be the same or different, and if nb is 2 or greater, each R bmay be the same or different, and if nc is 2 or greater, each R c may be the same or different, and if nd is 2 or greater, each R d may be the same or different, and if ne is 2 or greater, each R e may be the same or different, and if nf is 2 or greater, each R f They may be identical or different from each other,

[0194] In the above equation (1C), * indicates the bonding position with an adjacent atom.

[0195] Here, in the above equation (1A), A a To A d In the case where each of is a group derived from a benzene ring, at least one of na to nd is 3 or more, or R a to R d At least one of them may be an unsubstituted branched alkyl group having 4 to 15 carbon atoms, and

[0196] In the above formula (1B), A a and A c If each of is a group derived from a benzene ring, at least one of na, nc, ne, and nf is 3 or greater, or R a , R c , R e and R f At least one of them may be an unsubstituted branched alkyl group having 4 to 15 carbon atoms.

[0197] R a to R f In the above, the halogen atom, the unsubstituted alkyl group having 1 to 20 carbon atoms, the unsubstituted alkoxy group having 1 to 20 carbon atoms, and the unsubstituted aryl amino group having 6 to 20 carbon atoms are each the same as the unsubstituted groups in the descriptions of (a), (c), (d), and (e).

[0198] R a to R fIn the above, the unsubstituted haloalkyl group having 1 to 20 carbon atoms is the same as the description of the substituent that substitutes the group in (e) to (g).

[0199] R a to R d In this case, the substituted or unsubstituted monovalent aromatic hydrocarbon group and the substituted or unsubstituted monovalent aromatic heterocyclic group are each as described in (f) and (g) above.

[0200] R a to R d In the above, the unsubstituted alkyl amino group having 1 to 20 carbon atoms is the same as the description of the substituent that substitutes the group of (c) to (g).

[0201] R e and R f In the above, the unsubstituted haloalkoxy group having 1 to 20 carbon atoms may be a group in which at least one hydrogen atom of the alkoxy group described in (d) above is substituted by a halogen atom described in (a). For the sake of device lifespan, the halogen atom may be a fluorine atom. Specific examples of the haloalkoxy group may include, for instance, a trifluoromethoxy group, a trichloromethoxy group, a tribromomethoxy group, a triiodomethoxy group, etc. Among these, it may be a fluorinated alkoxy group or a trifluoromethoxy group.

[0202] In the above equations (1A) and (1B), the cases where na, nb, nc, nd, ne, and nf are 0 are the R corresponding to these. a , R b , R c , R d , R e , R f This means that does not exist. In other words, in the above equations (1A) and (1B), the case where na is 0 is R a It means that does not exist, and nb being 0 is R bIt means that does not exist, and nc being 0 is R c It means that does not exist, and nd being 0 is R d It means that does not exist. Also, in the above equation (1B), ne being 0 means R e It means that does not exist, and nf being 0 is R f This means that does not exist. That is, in the above equations (1A) and (1B), R a , R b , R c , R d , R e , R f The cyclic carbon atom described to be bonded is unsubstituted, and indicates that a hydrogen atom is bonded to the cyclic carbon atom.

[0203] In the above equations (1A) and (1B), A a To A d At least one of the devices represented by is A in the core part. a To A d The group represented by can bond to at least one cyclic carbon atom selected from the group consisting of a cyclic carbon atom adjacent to a cyclic carbon atom bonded to a nitrogen atom and a cyclic carbon atom adjacent to said cyclic carbon atom, of the portion of the group derived from the benzene ring to which the group can bond. In the above formulas (1A) and (1B), the substituents capable of bonding to such cyclic carbon atoms are not particularly limited, but examples include a terphenyl group, a phenyl group substituted with two or more alkyl groups having 1 to 4 carbon atoms, etc. Also, examples include an m-terphenyl group, a 2,6-di-tert-butylphenyl group, etc.

[0204] In the nitrogen-containing condensed ring compound according to the present invention, from the perspective of the peak wavelength of the emission spectrum and the color purity of the emission, the structure represented by Formula (1) or Formula (1B) may be the structure represented by Formula (2) or Formula (3). That is, one embodiment of the present invention relates to a nitrogen-containing condensed ring compound having the structure represented by Formula (2) or Formula (3). Furthermore, as one embodiment of an organic electroluminescent device material described below, an organic electroluminescent device material may be provided in which the structure represented by Formula (1) of the nitrogen-containing condensed ring compound is the structure represented by Formula (2) or Formula (3). Furthermore, as one embodiment of a fluorescent emitting agent described below, a fluorescent emitting agent may be provided in which the structure represented by Formula (1) of the nitrogen-containing condensed ring compound is the structure represented by Formula (2) or Formula (3). In a nitrogen-containing condensed ring compound, a material for an organic electroluminescent device, and a fluorescent light-emitting agent according to one embodiment of the present invention, in the following formulas (2) and (3), at least one of the substituents bonded to the core portion can bond to at least one cyclic carbon atom selected from the group consisting of a cyclic carbon atom adjacent to a cyclic carbon atom bonded to a nitrogen atom in the portion of the group derived from the benzene ring to which the substituent can bond in the core portion, and a cyclic carbon atom adjacent to said cyclic carbon atom. In the above formulas (2) and (3), the substituents capable of bonding to such cyclic carbon atoms are not particularly limited, but examples include a phenyl group substituted with two or more alkyl groups having 1 to 4 carbon atoms. Also, a 2,6-di-tert-butylphenyl group can be given as an example.In a nitrogen-containing condensed ring compound, a material for an organic electroluminescent device, and a fluorescent light-emitting agent according to one embodiment of the present invention, if the structure represented by the following formula (2) or the following formula (3) is a structure represented by the following formula (2') or the following formula (3'), the PLQY (Photoluminescence Quantum Yield) tends to be improved.

[0205]

[0206]

[0207]

[0208]

[0209] In the above equations (2) and (3), or in the above equations (2') and (3'),

[0210] R 5 to R 8 Each is independently a halogen atom, a cyano group, an unsubstituted alkyl group having 1 to 20 carbon atoms, an unsubstituted haloalkyl group having 1 to 20 carbon atoms, an unsubstituted alkoxy group having 1 to 20 carbon atoms, an unsubstituted alkyl amino group having 1 to 20 carbon atoms, or an unsubstituted aryl amino group having 6 to 20 carbon atoms, and

[0211] R 9 and R 10 Each is independently a halogen atom, a cyano group, an unsubstituted alkyl group having 1 to 20 carbon atoms, an unsubstituted haloalkyl group having 1 to 20 carbon atoms, an unsubstituted alkoxy group having 1 to 20 carbon atoms, an unsubstituted haloalkoxy group having 1 to 20 carbon atoms, or an unsubstituted aryl amino group having 6 to 20 carbon atoms, and

[0212] n5 to n8 are independently 0, 1, 2, 3, 4, or 5, and

[0213] n9 and n10 are independently 0, 1, 2, 3, or 4, and

[0214] Here, if any one of n5 to n10 (one, multiple, or all) is 2 or more, each R 5 , each R 6 , each R 7 , each R 8 , each R 9 or each R 10 They may be the same or different from each other.

[0215] As described above, in the above equations (2) and (3), or the above equations (2') and (3'), if any one of n5 to n10 (one, multiple, or all) is 2 or more, each R 5 , each R 6 , each R 7 , each R 8 , each R 9 , each R 10 They can be identical or different from each other. That is, when n5 is 2 or greater, each R 5 may be the same or different, and if n6 is 2 or greater, each R 6 may be the same or different, and if n7 is 2 or greater, each R 7 may be the same or different, and if n8 ​​is 2 or greater, each R 8 may be the same or different, and if n9 is 2 or greater, each R 9 may be the same or different, and if n10 is 2 or greater, each R 10 It may be the same or different.

[0216] R 5 to R 10 The halogen atom, the unsubstituted alkyl group having 1 to 20 carbon atoms, the unsubstituted alkoxy group having 1 to 20 carbon atoms, and the unsubstituted aryl amino group having 6 to 20 carbon atoms are each the same as the unsubstituted groups in the descriptions of (a), (c), (d), and (e).

[0217] R 5 to R10 The unsubstituted haloalkyl group having 1 to 20 carbon atoms in the above is the same as the description of the substituent that substitutes the group in (e) to (g).

[0218] R 5 to R 8 The substituted or unsubstituted monovalent aromatic hydrocarbon group and the substituted or unsubstituted monovalent aromatic heterocyclic group in each case are as described in (f) and (g) above.

[0219] R 5 to R 8 The unsubstituted alkyl amino group having 1 to 20 carbon atoms in the above is the same as the description of the substituent that substitutes the group of (c) to (g).

[0220] R 9 and R 10 In the above, the unsubstituted haloalkoxy group having 1 to 20 carbon atoms may be a group in which at least one hydrogen atom of the alkoxy group described in (d) above is substituted by a halogen atom described in (a). The halogen atom may be a fluorine atom for the sake of device lifespan. Specific examples of the haloalkoxy group include, for instance, trifluoromethoxy groups, trichloromethoxy groups, tribromomethoxy groups, triiodomethoxy groups, etc. Among these, it may be a fluorinated alkoxy group or a trifluoromethoxy group.

[0221] In the above equations (2) and (3), or the above equations (2') and (3'), the fact that n5, n6, n7, n8, n9, or n10 is 0 means that the R corresponding to these is 5 , R 6 , R 7 , R 8 , R 9 or R 10 This means that it does not exist. In other words, in the above equations (2) and (3), or the above equations (2') and (3'), n5 being 0 is R 5It means that does not exist, and n6 being 0 is R 6 This means that it does not exist, and n7 being 0 is R 7 This means that it does not exist, and n8 being 0 is R 8 This means that it does not exist. Also, in the above equation (3), or the above equation (3'), n9 being 0 means R 9 It means that does not exist, and n10 being 0 is R 10 This means that it does not exist. That is, R in the above equations (2) and (3), or in the above equations (2') and (3'). 5 , R 6 , R 7 , R 8 , R 9 or R 10 The cyclic carbon atom described to enable this bonding is unsubstituted, and it was indicated that a hydrogen atom is bonded to the said cyclic carbon atom.

[0222] n5 to n8 can be 0, 1, 2, or 3 independently of each other. Also, n9 and n10 can be 0 or 1 independently of each other.

[0223] Here, R 5 to R 8 It may be a halogen atom or an unsubstituted alkyl group having 1 to 20 carbon atoms in terms of luminescence color purity, luminescence efficiency, and device lifetime. It may also be an unsubstituted alkyl group having 1 to 20 carbon atoms, and may be an unsubstituted straight-chain or branched alkyl group having 1 to 20 carbon atoms. It may also be a methyl group, an isopropyl group, or a tert-butyl group.

[0224] Also R 9 and R 10may be a halogen atom, a cyano group, an unsubstituted alkyl group having 1 to 20 carbon atoms, an unsubstituted haloalkyl group having 1 to 20 carbon atoms, or an unsubstituted haloalkoxy group having 1 to 20 carbon atoms, from the perspective of luminescence color purity, luminescence efficiency, and device lifetime. Additionally, it may be a cyano group, an unsubstituted alkyl group having 1 to 20 carbon atoms, or an unsubstituted branched alkyl group having 1 to 20 carbon atoms. Here, the number of carbon atoms of the branched alkyl group may be 2 or more, or 3 or more, or 4 or more, from the perspective of solubility and luminescence color purity. Additionally, the number of carbon atoms of the branched alkyl group may be 10 or less, or 8 or less, or 6 or less, from the perspective of device lifetime. And R 9 and R 10 It can be a cyano group or a tert-butyl group.

[0225] In a nitrogen-containing condensed ring compound according to one embodiment of the present invention, R in Equation (2) (or Equation (2')) in terms of luminescence color purity, luminescence efficiency, and device lifespan 5 to R 8 At least one of them may be an unsubstituted alkyl group having 1 to 20 carbon atoms. Or R in Formula (3) (or Formula (3')). 5 , R 7 , R 9 and R 10 At least one of them may be an unsubstituted alkyl group having 1 to 20 carbon atoms. Furthermore, from this, one embodiment of the material for an organic electroluminescent device described below is R of Formula (2) (or Formula (2')) in a nitrogen-containing condensed ring compound. 5 to R 8 Examples of organic electroluminescent device materials include at least one of which is an unsubstituted alkyl group having 1 to 20 carbon atoms. Alternatively, R in the above formula (3) (or formula (3')) of a nitrogen-containing condensed ring compound 5 , R 7 , R 9 and R10 Examples of organic electroluminescent device materials include at least one of which is an unsubstituted alkyl group having 1 to 20 carbon atoms. In nitrogen-containing condensed ring compounds related to such embodiments, R in Formula (2) (or Formula (2')) above 5 to R 8 At least one of them may be a methyl group, an isopropyl group, or a tert-butyl group. Also, in the above formula (2) (or formula (2')), R 5 to R 8 At least one of them may be a methyl group or a tert-butyl group. In addition, in nitrogen-containing condensed ring compounds associated with these embodiments, R in Formula (3) (or Formula (3')) above 5 , R 7 , R 9 and R 10 At least one of them may be an unsubstituted straight-chain or branched alkyl group having 1 to 20 carbon atoms. Furthermore, in the structure represented by Formula (3) (or Formula (3')), R 5 and R 7 At least one of them is an unsubstituted straight-chain or branched alkyl group having 1 to 20 carbon atoms, and R 9 and R 10 At least one of them may be an unsubstituted branched alkyl group having 1 to 20 carbon atoms. And in the structure represented by Formula (3) (or Formula (3')), R 5 and R 7 At least one of them is a methyl group, an isopropyl group, or a tert-butyl group, and R 9 and R 10 At least one of them may be an isopropyl group or a tert-butyl group. Also, in the structure represented by Formula (3) (or Formula (3')), R 5 and R 7 At least one of them is a methyl group or a tert-butyl group and R 9 and R 10 At least one of them may be a tert-butyl group.

[0226] In addition, in a nitrogen-containing condensed ring compound according to another embodiment of the present invention, with respect to the peak wavelength of the emission spectrum, emission color purity, emission efficiency, and device lifetime, at least one of n5 to n8 in Equation (2) (or Equation (2')) is 3 or more, or R 5 to R 8 At least one of them may be an unsubstituted branched alkyl group having 4 to 15 carbon atoms. Or, in the above formula (3) (or formula (3')), at least one of n5, n7, n9, and n10 is 3 or more, or R 5 , R 7 , R 9 and R 10 At least one of them may be an unsubstituted branched alkyl group having 4 to 15 carbon atoms. Furthermore, from this, one embodiment of the material for an organic electroluminescent device described below is a nitrogen-containing condensed ring compound in which at least one of n5 to n8 of Formula (2) (or Formula (2')) is 3 or more, or R 5 to R 8 Examples of organic electroluminescent device materials include at least one of which is an unsubstituted branched alkyl group having 4 to 15 carbon atoms. Alternatively, at least one of n5, n7, n9, and n10 of Formula (3) (or Formula (3')) is 3 or more, or R 5 , R 7 , R 9 and R 10 Examples of materials for organic electroluminescent devices include at least one being an unsubstituted branched alkyl group having 4 to 15 carbon atoms. In the nitrogen-containing condensed ring compound associated with such an embodiment, at least one of n5 to n8 in Formula (2) (or Formula (2')) may be 3. Or R 5 to R 8At least one of them may be an isopropyl group or a tert-butyl group. Additionally, in the nitrogen-containing condensed ring compound associated with this embodiment, at least one of n5, n7, n9, and n10 in Formula (3) (or Formula (3')) may be 3. Or R 5 , R 7 , R 9 and R 10 At least one of them may be an unsubstituted branched alkyl group having 4 to 15 carbon atoms. In this case, R 5 and R 7 At least one of them is an unsubstituted straight-chain or branched alkyl group having 4 to 15 carbon atoms, and R 9 and R 10 At least one of them may be an unsubstituted branched alkyl group having 4 to 15 carbon atoms. And R 5 and R 7 At least one of them is a methyl group, an isopropyl group, or a tert-butyl group, and R 9 and R 10 At least one of them may be an isopropyl group or a tert-butyl group.

[0227] In a nitrogen-containing condensed ring compound according to another embodiment of the present invention, R 5 to R 8 is an independently unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted monovalent aromatic hydrocarbon group, or a substituted or unsubstituted monovalent aromatic heterocyclic group, and in the above formula (2) (or, above formula (2')), R 5 to R 8 Not all of them are unsubstituted alkyl groups having 1 to 20 carbon atoms, and on the other hand, not all of n5 to n8 are 0, and in the above formula (3) (or, above formula (3')), R 5 and R 7 Not all of them are unsubstituted alkyl groups with 1 to 20 carbon atoms, and on the other hand, n5 and n7 may not both be 0.

[0228] In the nitrogen-containing condensed ring compound according to the present invention, the structure represented by Formula (1), Formula (1A), Formula (1B), Formula (2), or Formula (3) may be a structure represented by one of Formulas (3-1) to (3-9) below (a structure represented by a formula selected from the group consisting of Formulas (3-1) to (3-9). Furthermore, from this, one embodiment of the organic electroluminescent device material described below may be an organic electroluminescent device material in which the structure represented by Formula (1), Formula (1A), Formula (1B), Formula (2), or Formula (3) of the nitrogen-containing condensed ring compound is a structure represented by one of Formulas (3-1) to (3-9) below (a structure represented by a formula selected from the group consisting of Formulas (3-1) to (3-9). In addition, as an embodiment of the fluorescent emitting agent described below, the structure of the nitrogen-containing condensed ring compound represented by the above formula (1), the above formula (1A), the above formula (1B), the above formula (2), or the above formula (3) may be represented by any one of the following formulas (3-1) to the following formula (3-9) (a structure represented by a formula selected from the group consisting of the following formulas (3-1) to the following formula (3-9). In the nitrogen-containing condensed ring compound, the material for an organic electroluminescent device, and the fluorescent emitting agent according to an embodiment of the present invention, in the following formulas (3-1) to the following formula (3-9), at least one of the substituents that bond to the core portion may bond to at least one cyclic carbon atom selected from the group consisting of a cyclic carbon atom adjacent to a cyclic carbon atom bonded to a nitrogen atom in the portion of the group derived from the benzene ring to which the substituent can bond in the core portion, and a cyclic carbon atom adjacent to the cyclic carbon atom.

[0229]

[0230]

[0231]

[0232]

[0233]

[0234] In the nitrogen-containing condensed ring compound according to the present invention, from the perspective of the peak wavelength of the emission spectrum, the color purity of the emission, the luminous efficiency, and the device lifespan, the structure represented by Formula (1), Formula (1A), or Formula (1B) may be the structure represented by Formula (7) or Formula (8). That is, one embodiment of the present invention relates to a nitrogen-containing condensed ring compound having a structure represented by Formula (7) or Formula (8). Furthermore, one embodiment of an organic electroluminescent device material described below may be an organic electroluminescent device material having a structure represented by Formula (7) or Formula (8) as the structure represented by Formula (1), Formula (1A), or Formula (1B) of the nitrogen-containing ring compound. In addition, as an embodiment of the fluorescent emitting agent described below, a fluorescent emitting agent may be provided in which the structure represented by the above formula (1), the above formula (1A), or the above formula (1B) of a nitrogen condensed ring compound is represented by the following formula (7) or the following formula (8).

[0235]

[0236]

[0237] In the above equations (7) and (8),

[0238] A 1 To A 4 is independently an unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted monovalent aromatic hydrocarbon group, or a substituted or unsubstituted monovalent aromatic heterocyclic group, and

[0239] R 11 and R 12Each is independently a halogen atom, a cyano group, an unsubstituted alkyl group having 1 to 20 carbon atoms, an unsubstituted haloalkyl group having 1 to 20 carbon atoms, an unsubstituted alkoxy group having 1 to 20 carbon atoms, an unsubstituted haloalkoxy group having 1 to 20 carbon atoms, or an unsubstituted aryl amino group having 6 to 20 carbon atoms, and

[0240] m1 to m4 are independently 0, 1, 2, 3, 4, or 5, and

[0241] n11 and n12 are independently 0, 1, 2, 3, or 4, and

[0242] Here, if m1 is 2 or greater, each A 1 It may be the same or different,

[0243] If m2 is 2 or greater, each A 2 It may be the same or different,

[0244] If m3 is 2 or greater, each A 3 It may be the same or different,

[0245] If m4 is 2 or greater, each A 4 It may be the same or different,

[0246] Also, if n11 is 2 or greater, each R 11 It may be the same or different,

[0247] If n12 is 2 or greater, each R 12 It may be the same or different,

[0248] In the above formula (7),

[0249] A 1 To A 4 Not all of them are unsubstituted alkyl groups having 1 to 20 carbon atoms, and on the other hand, not all of m1 to m4 are 0,

[0250] In the above equation (8),

[0251] A 1 and A 3Not all of them are unsubstituted alkyl groups having 1 to 20 carbon atoms, on the other hand, neither m1 nor m3 is 0;

[0252] A 1 To A 4 In this case, the substituted or unsubstituted monovalent aromatic hydrocarbon group and the substituted or unsubstituted monovalent aromatic heterocyclic group are each as described in (f) and (g) above.

[0253] A 1 To A 4 In this case, the unsubstituted alkyl group having 1 to 20 carbon atoms is the same as the unsubstituted group in the description of (c) above.

[0254] R 11 and R 12 In the above, the halogen atom, the unsubstituted alkyl group having 1 to 20 carbon atoms, the unsubstituted alkoxy group having 1 to 20 carbon atoms, and the unsubstituted aryl amino group having 6 to 20 carbon atoms are each the same as the unsubstituted groups in the descriptions of (a), (c), (d), and (e).

[0255] R 11 and R 12 In the above, the unsubstituted haloalkyl group having 1 to 20 carbon atoms is the same as the description of the substituent that substitutes the group in (e) to (g).

[0256] R 11 and R 12 In the above, the unsubstituted haloalkoxy group having 1 to 20 carbon atoms may be a group in which at least one hydrogen atom of the alkoxy group described in (d) above is substituted by the halogen atom described in (a). The halogen atom may be a fluorine atom from the perspective of device lifespan. Specific examples of the haloalkoxy group may include, for instance, a trifluoromethoxy group, a trichloromethoxy group, a tribromomethoxy group, a triiodomethoxy group, etc. Among these, it may be a fluorinated alkoxy group and may be a trifluoromethoxy group.

[0257] In the above equations (7) and (8), the fact that m1 to m4, n11, and n12 are 0 corresponds to A 1 , A 2 , A 3 , A 4 , R 11 , R 12 This means that does not exist. In other words, in the above equations (7) and (8), m1 being 0 means A 1 It means that does not exist, and m2 being 0 is A 2 It means that does not exist, and m3 being 0 is A 3 It means that does not exist, and that m4 is 0 is A 4 It means that does not exist. Also, in the above equation (8), n11 being 0 means R 11 It means that does not exist, and n12 being 0 is R 12 This means that does not exist. That is, in the above equations (7) and (8), A 1 , A 2 , A 3 , A 4 , R 11 , R 12 It was indicated that the cyclic carbon atom described for bonding is unsubstituted, and that a hydrogen atom is bonded to the said cyclic carbon atom.

[0258] m1 to m4 can be 2 independently of each other. Also, n11 and n12 can be 0 or 1 independently of each other.

[0259] A 1 To A 4From the perspective of the color purity of luminescence, luminescence efficiency, and device lifetime, it may be a substituted or unsubstituted monovalent aromatic hydrocarbon group having 6 to 12 carbon atoms, or a substituted or unsubstituted monovalent aromatic heterocyclic group. Additionally, it may be a substituted or unsubstituted monovalent aromatic heterocyclic group having 6 to 12 carbon atoms, or a monovalent aromatic heterocyclic group having 6 to 12 carbon atoms substituted or unsubstituted with an unsubstituted alkyl group having 1 to 20 carbon atoms. Furthermore, it may be a phenyl group substituted with an unsubstituted alkyl group having 1 to 20 carbon atoms. Here, the number of carbon atoms of the unsubstituted alkyl group that is the substituent is not particularly limited, but may be 1 to 10, or 1 to 8, or 1 to 6. A 1 To A 4 It may be, for example, a phenyl group substituted with a methyl group, a phenyl group substituted with a t-butyl group, or a phenyl group.

[0260] R 11 and R 12 From the perspective of color purity of luminescence, luminescent efficiency, and device lifetime, it may be a halogen atom, a cyano group, an unsubstituted alkyl group having 1 to 20 carbon atoms, an unsubstituted haloalkyl group having 1 to 20 carbon atoms, or an unsubstituted haloalkoxy group having 1 to 20 carbon atoms. Additionally, it may be a cyano group, an unsubstituted alkyl group having 1 to 20 carbon atoms, or an unsubstituted branched alkyl group having 1 to 20 carbon atoms. Here, the number of carbon atoms of the branched alkyl group may be 2 or more, or 3 or more, or 4 or more, from the perspective of solubility and color purity of luminescence. Additionally, the number of carbon atoms of the branched alkyl group may be 10 or less, or 8 or less, or 6 or less, from the perspective of device lifetime. And R 11 and R 12 It can be, for example, a tert-butyl group.

[0261] In a nitrogen-containing condensed ring compound, a material for an organic electroluminescent device, and a fluorescent light-emitting agent according to one embodiment of the present invention, in the above formulas (7) and (8), at least one of the substituents bonded to the core portion can bond to at least one cyclic carbon atom selected from the group consisting of a cyclic carbon atom adjacent to a cyclic carbon atom bonded to a nitrogen atom in the portion of the group derived from the benzene ring to which the substituent can bond in the core portion, and a cyclic carbon atom adjacent to the cyclic carbon atom. In the above formulas (7) and (8), the substituents capable of bonding to such cyclic carbon atoms are not particularly limited, but examples include a terphenyl group, a phenyl group substituted with two or more alkyl groups having 1 to 4 carbon atoms, etc. Also, examples include an m-terphenyl group, a 2,6-di-tert-butylphenyl group, etc.

[0262] Among the above equations (7) and (8), for example, it may be equation (8).

[0263] In the nitrogen-containing condensed ring compound according to the present invention, the structure represented by Formula (1), Formula (1A), Formula (1B), Formula (7), or Formula (8) may be a structure represented by a formula selected from the group consisting of Formulas (9) to (11). Furthermore, as one embodiment of the organic electroluminescent device material described therefrom, the structure represented by Formula (1), Formula (1A), Formula (1B), Formula (7), or Formula (8) of the nitrogen-containing condensed ring compound may be a structure represented by a formula selected from the group consisting of Formulas (9) to (11). In addition, as an embodiment of the fluorescent emitting agent described below, there may be a fluorescent emitting agent having a structure selected from the group consisting of the following formulas (9) to (11), wherein the structure of the nitrogen condensed ring compound represented by the above formula (1), the above formula (1A), the above formula (1B), the above formula (7), or the above formula (8) is represented by the above formula (9).

[0264]

[0265]

[0266]

[0267] In the above formulas (9) to (11),

[0268] R 101 to R 112 is an independently unsubstituted alkyl group having 1 to 20 carbon atoms, and

[0269] n101 to n112 are independently 0, 1, 2 or 3, and

[0270] If n101 is 2 or greater, each R 101 may be the same or different, and if n102 is 2 or greater, each R 102 may be the same or different, and if n103 is 2 or greater, each R103 may be the same or different, and if n104 is 2 or greater, each R 104 may be the same or different, and if n105 is 2 or greater, each R 105 may be the same or different, and if n106 is 2 or greater, each R 106 may be the same or different, and if n107 is 2 or greater, each R 107 may be the same or different, and if n108 is 2 or greater, each R 108 may be the same or different, and if n109 is 2 or greater, each R 109 may be the same or different, and if n110 is 2 or greater, each R 110 may be the same or different, and if n111 is 2 or greater, each R 111 may be the same or different, and if n112 is 2 or greater, each R 112 It may be the same or different.

[0271] Or, if n101 is 2 or greater, each R 101 can be the same, and if n102 is 2 or greater, each R 102 can be the same, and if n103 is 2 or greater, each R 103 can be the same, and if n104 is 2 or greater, each R 104 can be the same, and if n105 is 2 or greater, each R 105 can be the same, and if n106 is 2 or greater, each R 106 can be the same, and if n107 is 2 or greater, each R 107 can be the same, and if n108 is 2 or greater, each R 108 can be the same, and if n109 is 2 or greater, each R 109 can be the same, and if n110 is 2 or greater, each R 110 can be the same, and if n111 is 2 or greater, each R 111 can be the same, and if n112 is 2 or greater, each R112 It can be the same.

[0272] From the perspective of color purity of light emission, light emission efficiency, and device lifespan, among the above equations (9) to (11), it may be equation (11).

[0273] In the above equations (9) to (11), n101 to n112 being 0 corresponds to R 101 , R 102 , R 103 , R 104 , R 105 , R 106 , R 107 , R 108 , R 109 , R 110 , R 111 , R 112 This means that does not exist. In other words, in the above equations (9) to (11), when n101 is 0, R 101 This means that does not exist, and when n102 is 0, R 102 This means that does not exist, and when n103 is 0, R 103 This means that does not exist, and when n104 is 0, R 104 This means that does not exist, and when n105 is 0, R 105 This means that does not exist, and when n106 is 0, R 106 This means that does not exist, and when n107 is 0, R 107 This means that does not exist, and when n108 is 0, R 108 This means that does not exist. Also, in the above equation (10), when n109 is 0, R 109It means that does not exist, and when n110 is 0, R 110 This means that does not exist. And in the above equation (11), when n111 is 0, R 111 It means that does not exist, and when n112 is 0, R 112 This means that R does not exist. That is, in the above equations (9) to (11), R 101 , R 102 , R 103 , R 104 , R 105 , R 106 , R 107 , R 108 , R 109 , R 110 , R 111 , R 112 The cyclic carbon atom described to be bonded is unsubstituted, and indicates that a hydrogen atom is bonded to the cyclic carbon atom.

[0274] n101 to n108 can be 0, 1, 2 or 3 independently of each other, and can be 0. n109 and n110 can be 0, 1 or 2 independently of each other. n111 and n112 can be 0 or 1 independently of each other.

[0275] R 101 to R 112 In this case, the unsubstituted alkyl group having 1 to 20 carbon atoms is the same as the unsubstituted group in the description of (c) above.

[0276] R 101 to R 112In the above, the unsubstituted alkyl group having 1 to 20 carbon atoms may be an unsubstituted alkyl group having 1 to 10 carbon atoms from the perspective of color purity of luminescence, luminescence efficiency, and device lifespan. In addition, it may be an unsubstituted alkyl group having 1 to 8 carbon atoms, or an unsubstituted alkyl group having 1 to 6 carbon atoms. And, for example, it may be a t-butyl group.

[0277] Among these, in the above equation (11), n101, n102, n105, n106, n1111, and n112 are independently 0 or 1, and R 101 , R 102 , R 105 , R 106 , R 111 , R 112 The unsubstituted alkyl group having 1 to 20 carbon atoms in the above may be an unsubstituted alkyl group having 1 to 6 carbon atoms. Also, for example, n101, n102, n105, n106, n111, and n112 may all be 0.

[0278] In a nitrogen-containing condensed ring compound, a material for an organic electroluminescent device, and a fluorescent light-emitting agent according to one embodiment of the present invention, in the above formulas (9) to (11), at least one of the substituents bonded to the core portion can bond to at least one cyclic carbon atom selected from the group consisting of a cyclic carbon atom adjacent to a cyclic carbon atom bonded to a nitrogen atom in the portion of the group derived from the benzene ring to which the substituent can bond in the core portion, and a cyclic carbon atom adjacent to the cyclic carbon atom. In the above formula (9), the substituents that can bond to such cyclic carbon atoms are not particularly limited, but a terphenyl group can be given as an example. Also, an m-terphenyl group can be given as an example. In the above formula (10), the substituents that can bond to such cyclic carbon atoms are not particularly limited, but examples include a terphenyl group, a phenyl group substituted with two or more alkyl groups having 1 to 4 carbon atoms, etc. In addition, m-terphenyl groups, 2,6-di-tert-butylphenyl groups, etc. can be given as specific examples. In the above formula (11), the substituents that can bond to such cyclic carbon atoms are not particularly limited, but terphenyl groups can be given as examples. In addition, m-terphenyl groups can be given as specific examples.

[0279] In the nitrogen-containing condensed ring compound according to the present invention, from the perspective of the peak wavelength of the emission spectrum, the color purity of the emission, the luminous efficiency, and the lifespan of the device, the structure represented by Formula (1), Formula (1A), or Formula (1B) may be a structure represented by a formula selected from the group consisting of Formulas (12) to (14). That is, one embodiment of the present invention relates to a nitrogen-containing condensed ring compound having a structure represented by a formula selected from the group consisting of Formulas (12) to (14). Furthermore, as one embodiment of an organic electroluminescent device material described therein, the structure represented by Formula (1), Formula (1A), or Formula (1B) of the nitrogen-containing ring compound may be a structure represented by a formula selected from the group consisting of Formulas (12) to (14). In addition, as an embodiment of the fluorescent emitting agent described below, there may be a fluorescent emitting agent having a structure represented by the above formula (1), the above formula (1A), or the above formula (1B) of a nitrogen condensed ring compound, which is selected from the group consisting of the following formulas (12) to (14).

[0280]

[0281]

[0282]

[0283] In the above formulas (12) to (14),

[0284] A 201 To A 204 is independently an unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted monovalent aromatic hydrocarbon group, or a substituted or unsubstituted monovalent aromatic heterocyclic group, and

[0285] R 201 and R 202Each is independently a halogen atom, a cyano group, an unsubstituted alkyl group having 1 to 20 carbon atoms, an unsubstituted haloalkyl group having 1 to 20 carbon atoms, an unsubstituted alkoxy group having 1 to 20 carbon atoms, an unsubstituted alkyl amino group having 1 to 20 carbon atoms, an unsubstituted aryl amino group having 6 to 20 carbon atoms, a substituted or unsubstituted monovalent aromatic hydrocarbon group, or a substituted or unsubstituted monovalent aromatic heterocyclic group, and

[0286] R 203 and R 204 Each is independently a halogen atom, a cyano group, an unsubstituted alkyl group having 1 to 20 carbon atoms, an unsubstituted haloalkyl group having 1 to 20 carbon atoms, an unsubstituted alkoxy group having 1 to 20 carbon atoms, an unsubstituted haloalkoxy group having 1 to 20 carbon atoms, or an unsubstituted aryl amino group having 6 to 20 carbon atoms, and

[0287] n201 and n202 are independently 0, 1, 2, 3, 4, or 5, and

[0288] n203 and n204 are independently 0, 1, 2, 3, or 4, and

[0289] Here, each A 201 may be the same or different, and each A 202 may be the same or different, and each A 203 may be the same or different, and each A 204 It may be the same or different,

[0290] 2 or more A 201 , 2 or more A 202 , 2 or more A 203 , 2 or more A 204 Each can form a ring, and

[0291] Also, if n201 is 2 or greater, each R 201 may be the same or different, and if n202 is 2 or greater, each R 202may be the same or different, and if n203 is 2 or greater, each R 203 may be the same or different, and if n204 is 2 or greater, each R 204 It may be the same or different,

[0292] In the above equation (12), each A 201 , each A 202 , each A 203 , each A 204 Each is not entirely an unsubstituted alkyl group having 1 to 20 carbon atoms, and

[0293] In the above equation (13), each A 202 , each A 204 Each is not entirely an unsubstituted alkyl group having 1 to 20 carbon atoms, and

[0294] In the above equation (14), each A 201 , each A 203 Each of them is not an unsubstituted alkyl group having 1 to 20 carbon atoms.

[0295] Additionally, in the above formulas (12) to (14), C represents a carbon atom.

[0296] A 201 To A 204 , R 201 , R 202 In the above, the substituted or unsubstituted monovalent aromatic hydrocarbon group and the substituted or unsubstituted monovalent aromatic heterocyclic group are each as described in (f) and (g).

[0297] A 201 To A 204 , R 201 to R 204 In this case, the unsubstituted alkyl group having 1 to 20 carbon atoms is the same as the unsubstituted group in the description of (c) above.

[0298] R 201 to R 204In the above, the halogen atom, the unsubstituted alkoxy group having 1 to 20 carbon atoms, and the unsubstituted aryl amino group having 6 to 20 carbon atoms are each the same as the unsubstituted groups in the descriptions of (a), (d), and (e).

[0299] R 201 to R 204 In the above, the unsubstituted haloalkyl group having 1 to 20 carbon atoms is the same as the description of the substituent that substitutes the group of (e) to (g).

[0300] R 201 and R 202 In the above, the unsubstituted alkyl amino group having 1 to 20 carbon atoms is the same as the description of the substituent that substitutes the group of (c) to (g).

[0301] R 203 and R 204 In the above, the unsubstituted haloalkoxy group having 1 to 20 carbon atoms may be a group in which at least one hydrogen atom of the alkoxy group described in (d) above is substituted by the halogen atom described in (a). As for the halogen atom, from the perspective of device lifespan, it may be a fluorine atom. Specific examples of the haloalkoxy group may include, for instance, a trifluoromethoxy group, a trichloromethoxy group, a tribromomethoxy group, a triiodomethoxy group, etc. Among these, it may be a fluorinated alkoxy group, and specifically, it may be a trifluoromethoxy group.

[0302] In the above equation (13), n201 and n202 being 0 corresponds to R 201 , R 202 It means that does not exist. In other words, n201 being 0 means R 201 It means that does not exist, and n202 being 0 is R 202 This means that it does not exist. That is, in the above equation (13), R 201 , R 202The cyclic carbon atom described to be bonded is unsubstituted, and indicates that a hydrogen atom is bonded to the cyclic carbon atom.

[0303] In the above equation (14), n203 and n204 being 0 corresponds to R 203 , R 204 It means that does not exist. In other words, n203 being 0 means R 203 It means that does not exist, and n204 being 0 is R 204 This means that it does not exist. That is, in the above equation (14), R 203 , R 204 The cyclic carbon atom described to be bonded is unsubstituted, and indicates that a hydrogen atom is bonded to the cyclic carbon atom.

[0304] n201 and n202 can be 0, 1, or 2 independently of each other, and can be 2. n203 and n204 can be 0 or 1 independently of each other, and, for example, can be 0.

[0305] A 201 To A 204 a. In the case where each is a substituted or unsubstituted monovalent aromatic hydrocarbon group, or a substituted or unsubstituted monovalent aromatic heterocyclic group, from the perspective of color purity and luminescence efficiency of the luminescence, it may be a substituted or unsubstituted monovalent aromatic hydrocarbon group. In addition, it may be a substituted or unsubstituted monovalent aromatic heterocyclic group having 6 to 12 carbon atoms, or a monovalent aromatic heterocyclic group having 6 to 12 carbon atoms substituted or unsubstituted with an unsubstituted alkyl group having 1 to 20 carbon atoms. And it may be a phenyl group substituted with an unsubstituted alkyl group having 1 to 20 carbon atoms. Here, the number of carbon atoms of the unsubstituted alkyl group that is the substituent is not particularly limited, but may be 1 to 10, or 1 to 8, or 1 to 6. A201 To A 204 can be a phenyl group substituted with a t-butyl group, a phenyl group, for example, a phenyl group.

[0306] A 201 To A 204 a. In the case where each is an unsubstituted alkyl group having 1 to 20 carbon atoms, the unsubstituted alkyl group having 1 to 20 carbon atoms may be an unsubstituted alkyl group having 1 to 10 carbon atoms from the perspective of color purity of luminescence, luminescence efficiency, and device lifespan. In addition, it may be an unsubstituted alkyl group having 1 to 8 carbon atoms, or an unsubstituted alkyl group having 1 to 6 carbon atoms. And, for example, it may be a methyl group.

[0307] R 201 to R 204 As, from the perspective of emission wavelength and luminescence efficiency, it may be a halogen atom, a cyano group, an unsubstituted alkyl group having 1 to 20 carbon atoms, an unsubstituted haloalkyl group having 1 to 20 carbon atoms, or an unsubstituted haloalkoxy group having 1 to 20 carbon atoms. It may also be an unsubstituted alkyl group having 1 to 20 carbon atoms. Here, the number of carbon atoms of the unsubstituted alkyl group serving as a substituent is not particularly limited, but may be 1 to 10, 1 to 8, or 1 to 6. Furthermore, as the unsubstituted alkyl group having 1 to 20 carbon atoms, it may be a branched alkyl group. And R 201 to R 204 As for, for example, it can be a t-butyl group.

[0308] 2 or more A 201 , 2 or more A 202 , 2 or more A 203 , 2 or more A 204 Each of these can form a ring, and examples of the rings formed by these include, for instance, the fluorene ring.

[0309] Among the above formulas (12) to (14), for example, it may be the above formula (13).

[0310] In a nitrogen-containing condensed ring compound, a material for an organic electroluminescent device, and a fluorescent light-emitting agent according to one embodiment of the present invention, in the above formulas (12) to (14), at least one of the substituents bonded to the core portion can bond to at least one cyclic carbon atom selected from the group consisting of a cyclic carbon atom adjacent to a cyclic carbon atom bonded to a nitrogen atom in the portion of the group derived from the benzene ring to which the substituent can bond in the core portion, and a cyclic carbon atom adjacent to the cyclic carbon atom. In the above formula (13), the substituents capable of bonding to such cyclic carbon atoms are not particularly limited, but examples include a terphenyl group, a phenyl group substituted with two or more alkyl groups having 1 to 4 carbon atoms, etc. Also, specific examples include an m-terphenyl group, a 2,6-di-tert-butylphenyl group, etc.

[0311] In the nitrogen-containing condensed ring compound according to the present invention, the structure represented by a formula selected from the group consisting of formula (1), formula (1A), formula (1B), or formulas (12) to (13) may be a structure represented by a formula selected from the group consisting of formulas (15) to (17). Furthermore, as one embodiment of the organic electroluminescent device material described therefrom, the structure represented by a formula selected from the group consisting of formula (1), formula (1A), formula (1B), or formulas (12) to (14) of the nitrogen-containing condensed ring compound may be an organic electroluminescent device material represented by a structure selected from the group consisting of formulas (15) to (17). In addition, as an embodiment of the fluorescent emitting agent described below, there may be a fluorescent emitting agent having a structure selected from the group consisting of the above formula (1), above formula (1A), above formula (1B), above formula (12) to above formula (14) of a nitrogen-containing condensed ring compound, or a structure selected from the group consisting of the following formulas (15) to below formula (17).

[0312]

[0313]

[0314]

[0315] In the above formulas (15) to (17),

[0316] R 301 to R 308 is independently an unsubstituted alkyl group having 1 to 20 carbon atoms, and n301 to n308 are independently 0, 1, 2 or 3, and

[0317] Here, if n301 is 2 or greater, each R 301may be the same or different, and if n302 is 2 or greater, each R 302 may be the same or different, and if n303 is 2 or greater, each R 303 may be the same or different, and if n304 is 2 or greater, each R 304 may be the same or different, and if n305 is 2 or greater, each R 305 may be the same or different, and if n306 is 2 or greater, each R 306 may be the same or different, and if n307 is 2 or greater, each R 307 may be the same or different, and if n308 is 2 or greater, each R 308 It may be the same or different.

[0318] Or, if n301 is 2 or greater, each R 301 can be the same, and if n302 is 2 or greater, each R 302 can be the same, and if n303 is 2 or greater, each R 303 can be the same, and if n304 is 2 or greater, each R 304 can be the same, and if n305 is 2 or greater, each R 305 can be the same, and if n306 is 2 or greater, each R 306 can be the same, and if n307 is 2 or greater, each R 307 can be the same, and if n308 is 2 or greater, each R 308 It can be the same.

[0319] From the perspective of the emission wavelength, among the above equations (15) to (17), it may be the above equation (16).

[0320] In the above formulas (15) to (17), n301 to n308 being 0 corresponds to R 301 , R 302 , R 303 , R 304 , R 305 , R306 , R 307 , R 308 This means that it does not exist. In other words, in the above equations (15) to (17), n301 being 0 means R 301 It means that does not exist, and n302 being 0 is R 302 It means that does not exist, and n303 being 0 is R 303 It means that does not exist, and n304 being 0 is R 304 It means that does not exist. Also, in the above equation (16), n305 being 0 means R 305 It means that does not exist, and n306 being 0 is R 306 This means that does not exist. Also, in the above equation (17), n307 being 0 means R 307 It means that does not exist, and n308 being 0 is R 308 This means that R does not exist. That is, in the above equations (15) to (17), R 301 , R 302 , R 303 , R 304 , R 305 , R 306 , R 307 , R 308 The cyclic carbon atom described to be bonded is unsubstituted, and indicates that a hydrogen atom is bonded to the cyclic carbon atom.

[0321] n301 to n304 may be 0, 1, or 2 independently of each other, and may be 0. n305 and n306 may be 0, 1, or 2 independently of each other. n307 and n308 may be 0 or 1 independently of each other.

[0322] R 301 to R 308 In this case, the unsubstituted alkyl group having 1 to 20 carbon atoms is the same as the unsubstituted group in the description of (c) above.

[0323] R 301 to R 308 In the above, the unsubstituted alkyl group having 1 to 20 carbon atoms may be an unsubstituted alkyl group having 1 to 10 carbon atoms from the perspective of emission wavelength, color purity of emission, luminous efficiency, and device lifetime. In addition, it may be an unsubstituted alkyl group having 1 to 8 carbon atoms, or an unsubstituted alkyl group having 1 to 6 carbon atoms. In addition, it may be a methyl group or a t-butyl group, and for example, a t-butyl group. In addition, the unsubstituted alkyl group having 1 to 20 carbon atoms may be a branched alkyl group, for example.

[0324] Among these, in the above equation (16), n302, n304, n305 and n306 are independently 0, 1 or 2, and R 302 , R 304 , R 305 , R 306 In the above, the unsubstituted alkyl group having 1 to 20 carbon atoms may be an unsubstituted alkyl group having 1 to 6 carbon atoms. Additionally, n302 and n304 are independently 0 or 1, n305 and n306 are independently 0, 1, or 2, and R 302 , R 304 , R 305 , R 306 In the above, the unsubstituted alkyl group having 1 to 20 carbon atoms may be an unsubstituted alkyl group having 1 to 6 carbon atoms. For example, n302 and n304 are both 0, while n305 and n306 are independently 1 or 2, and R 301 to R 304 In the above, the unsubstituted alkyl group having 1 to 20 carbon atoms may be an unsubstituted branched alkyl group having 1 to 6 carbon atoms. Also, for example, n302 and n304 are both 0, while n305 and n306 are independently 1 or 2, and R 301 to R 304In the above, the unsubstituted alkyl group having 1 to 20 carbon atoms may be a t-butyl group. Also, for example, n302 and n304 are both 0, while n305 and n306 are both 2, and R 305 and R 306 The unsubstituted alkyl group having 1 to 20 carbon atoms in the above may be a t-butyl group.

[0325] In a nitrogen-containing condensed ring compound, a material for an organic electroluminescent device, and a fluorescent light-emitting agent according to one embodiment of the present invention, in the above formulas (15) to (17), at least one of the substituents bonded to the core portion can bond to at least one cyclic carbon atom selected from the group consisting of a cyclic carbon atom adjacent to a cyclic carbon atom bonded to a nitrogen atom in the portion of the group derived from the benzene ring to which the substituent can bond in the core portion, and a cyclic carbon atom adjacent to the cyclic carbon atom. In the above formula (16), the substituents capable of bonding to such cyclic carbon atoms are not particularly limited, but examples include a phenyl group substituted with two or more alkyl groups having 1 to 4 carbon atoms. In addition, a 2,6-di-tert-butylphenyl group can be given as a specific example.

[0326] Thus, in the nitrogen-containing condensed ring compound according to the present invention, the structure represented by Formula (1) may be the structure represented by Formula (1A) or Formula (1B) from the perspective of the peak wavelength of the emission spectrum, the color purity of the emission, the luminous efficiency, and the device lifespan. That is, one embodiment of the present invention relates to a nitrogen-containing condensed ring compound having the structure represented by Formula (1A) or Formula (1B). Furthermore, as one embodiment of an organic electroluminescent device material described below, an organic electroluminescent device material may be provided in which the structure represented by Formula (1) of the nitrogen-containing condensed ring compound is the structure represented by Formula (1A) or Formula (1B). Furthermore, as one embodiment of a fluorescent emitting agent described below, a fluorescent emitting agent may be provided in which the structure represented by Formula (1) of the nitrogen-containing condensed ring compound is the structure represented by Formula (1A) or Formula (1B). In addition, in such a case, an embodiment of the above formula (1A) and the above formula (1B) is as described above, respectively. In such a case, the above formula (1A) and the above formula (1B) may satisfy the following:

[0327] In the above equation (1A), A a To A d If each of is a group derived from a benzene ring, at least one of na to nd is 3 or more, or R a to R d At least one of them is an unsubstituted branched alkyl group having 4 to 15 carbon atoms, and

[0328] In the above formula (1B), A a To A d If each of is a group derived from a benzene ring, at least one of na, nc, ne, and nf is 3 or greater, or R a , R c , R e and R fAt least one of them is an unsubstituted branched alkyl group having 4 to 15 carbon atoms.

[0329] A nitrogen-containing condensed ring compound according to one embodiment of the present invention may have one or more substituents including a group derived from an aromatic ring that is bonded to a core portion through a single bond. In the nitrogen-containing condensed ring compound, the dihedral angle between the core portion and at least one group derived from an aromatic ring that is bonded to the core portion through a single bond is not particularly limited, but may be 50° or more. The dihedral angle may be 55° or more, or 60° or more. The dihedral angle may be 90° or less. That is, when the nitrogen-containing condensed ring compound according to one embodiment of the present invention has one or more substituents including a group derived from an aromatic ring that is bonded to the core portion through a single bond, at least one dihedral angle among the dihedral angles between the core portion and the group derived from the aromatic ring that is bonded to the core portion through a single bond may be within the above range. In this range, the difference between the Full Width at Half Maximum (FWHM) of the emission spectrum peak in photoluminescence (PL) obtained in a solution state and the Full Width at Half Maximum (FWHM) of the emission spectrum peak in a film state becomes small. As a result, a small Full Width at Half Maximum (FWHM) of the emission spectrum peak can be obtained even in a film state, and a narrow Full Width at Half Maximum (FWHM) of the emission spectrum peak can also be obtained for organic electroluminescent devices. Additionally, in this specification, the dihedral angle can be expressed as 0° or greater and 90° or less.

[0330] In a substituent comprising a group derived from an aromatic ring that is bonded to the core through a single bond, the group derived from the aromatic ring that is bonded to the core through a single bond may be a group derived from an aromatic hydrocarbon ring or a group derived from an aromatic heterocyclic ring. The description of the aromatic hydrocarbon ring is the same as the description of the aromatic hydrocarbon ring in the description of the monovalent aromatic hydrocarbon group in (f) above. An example of an aromatic hydrocarbon ring is the same as the description of the aromatic hydrocarbon ring in the description of the monovalent aromatic hydrocarbon group in (f) above. The description of the aromatic heterocyclic ring is the same as the description of the aromatic heterocyclic ring in the heterocyclic group of valence 1 in (g) above. An example of a heterocyclic ring having aromaticity is the same as the description of a heterocyclic ring having aromaticity in the heterocyclic group of (g) above.

[0331] The dihedral angle between a core and a tilde derived from an aromatic ring bonded to the core via a single bond can be calculated using GaussView (Gaussian Inc.) from the most stabilized structure calculated by "calculation by Density Functional Theory (DFT)." The dihedral angle between a core and a tilde derived from an aromatic ring bonded to the core via a single bond, as discussed herein, is defined as the angle formed by the triangle Δα2α1β1 with vertices α2, α1, and β1, and the triangle Δβ2β1α1 with vertices β2, β1, and α1, where α1 is the atom of the core bonded to the substituent, α2 is the atom closest to α1 in the core, β1 is the atom of the substituent bonded to the core, and β2 is the atom closest to β1 in the substituent. Additionally, detailed information on the calculation method is described in the examples.

[0332] In a substituent comprising a group derived from an aromatic ring that is bonded to the core portion via a single bond, the group derived from the aromatic ring that is bonded to the core portion via a single bond may be a group selected from the group consisting of a group derived from an aromatic hydrocarbon ring, a group derived from a carbazole ring, and a group derived from a dibenzofuran ring. Additionally, the group derived from an aromatic ring that is bonded to the core portion via a single bond may be a group selected from the group consisting of a group derived from an aromatic hydrocarbon ring, a group derived from a carbazole ring, and a group derived from a dibenzofuran ring as a whole. In a substituent comprising a group derived from an aromatic ring that is bonded to the core portion via a single bond, the group derived from the aromatic ring that is bonded to the core portion via a single bond may be a group derived from an aromatic ring contained within the same plane. Groups derived from aromatic rings contained within the same plane may include, for example, groups derived from a benzene ring, groups derived from a carbazole ring, groups derived from a dibenzofuran ring, groups derived from a fluorene ring, etc. However, groups derived from aromatic rings contained within the same plane are not limited to these. Accordingly, in a substituent including a group derived from an aromatic ring that is bonded to the core portion through a single bond, the group derived from an aromatic ring that is bonded to the core portion through a single bond may be a group derived from a benzene ring, a group derived from a carbazole ring, a group derived from a dibenzofuran ring, and a group derived from a fluorene ring. In addition, the group derived from an aromatic ring that is bonded to the core portion through a single bond may be a group selected from the group consisting of a group derived from a benzene ring, a group derived from a carbazole ring, and a group derived from a dibenzofuran ring, and, for example, may be a group derived from a benzene ring.

[0333] A nitrogen-containing condensed ring compound according to one embodiment of the present invention may include one or more substituents selected from the group consisting of a group derived from a benzene ring that is bonded to the core via a single bond, a group derived from a carbazole ring that is bonded to the core via a single bond, and a group derived from a dibenzofuran ring that is bonded to the core via a single bond, while having a dihedral angle of at least one group selected from the group consisting of a group derived from a benzene ring that is bonded to the core via a single bond, a group derived from a carbazole ring that is bonded to the core via a single bond, and a group derived from a dibenzofuran ring that is bonded to the core via a single bond, wherein the dihedral angle with at least one of the groups is 50° or more. The dihedral angle may be 55° or more, or 60° or more. The dihedral angle may be 90° or less. A nitrogen-containing condensed ring compound according to one embodiment of the present invention may include one or more substituents including a group derived from a benzene ring that is bonded to a core portion through a single bond, and having a dihedral angle of 50° or more with at least one group derived from a benzene ring that is bonded to the core portion through a single bond. The dihedral angle may be 55° or more, or 60° or more. The dihedral angle may be 90° or less.

[0334] The nitrogen-containing condensed ring compound according to the present invention has a peak wavelength of the emission spectrum within the blue wavelength region and can also realize luminescence with high color purity. Additionally, in this specification, the blue wavelength region refers to a wavelength range of 380 nm to 500 nm. The peak wavelength of emission in the photoluminescence (PL) of the nitrogen-containing condensed ring compound according to the present invention is not particularly limited, but may be within the range of 440 nm to 480 nm. Furthermore, the peak wavelength may emit light having a peak in the wavelength region of 445 nm to 470 nm, or it may be 450 nm to 470 nm, or, for example, within the range of 450 nm to 465 nm. If the peak wavelength is within the above range, good luminescence, particularly good blue luminescence, can be obtained. The range of the Full Width at Half Maximum (FWHM) of the peak of the emission spectrum in photoluminescence (PL) may be, for example, 30 nm or less, or 20 nm or less, or 15 nm or less (a lower limit greater than 0 nm). Additionally, the peak wavelength of emission in PL and the FWHM of the peak of the emission spectrum in photoluminescence can be measured using the F7000 spectrofluorescence photometer manufactured by Hitachi High-Tech Corporation. More specifically, 1×10 of the nitrogen-containing condensed ring compound according to the present invention -5 M(= mol / dm 3 For a toluene solution of mol / L, it can be evaluated by measuring at room temperature with an excitation wavelength of 360 nm using the spectrofluorescence photometer above.

[0335] The narrow FWHM, TADF characteristics, and emission wavelength required for the molecule used as a dopant can be predicted by performing quantum chemical calculations.

[0336] In a condensed ring compound according to one embodiment of the present invention, the HOMO (Highest Occupied Molecular Orbital) energy is not particularly limited but may be -5.8 eV or higher. Additionally, the HOMO energy may be -5.6 eV or higher, or -5.4 eV or higher. On the other hand, the HOMO energy may be -4.6 eV or lower. Additionally, the HOMO energy may be -4.8 eV or lower, or -5.0 eV or lower. Within the above ranges, the difference in HOMO energy with that of a general host material used as an organic electroluminescent device becomes smaller. As a result, the increase in driving voltage due to hole trap formation is further suppressed.

[0337] In a condensed ring compound according to one embodiment of the present invention, the LUMO (Lowest Unoccupied Molecular Orbital) energy is not particularly limited but may be -2.4 eV or higher. Additionally, the LUMO energy may be -2.2 eV or higher, or -2.1 eV or higher. Furthermore, the LUMO energy may be -2.0 eV or higher. Meanwhile, the LUMO energy may be -0.8 eV or lower. Additionally, the LUMO energy may be -1.0 eV or lower, or -1.1 eV or lower. Furthermore, the LUMO energy may be -1.2 eV or lower. Within the above ranges, the difference from the LUMO energy of a general host material used as an organic electroluminescent device becomes smaller. As a result, the rise in driving voltage due to electron trap formation is further suppressed.

[0338] In a condensed ring compound according to one embodiment of the present invention, the energy of the first adiabatic excited singlet state (S1) (hereinafter also referred to as "diabatic S1 excitation energy") (eV) can be obtained by converting it into a light wavelength (nm). The range of the peak of the fluorescence wavelength is the same as the range of the peak wavelength of emission in the photoluminescence (PL) above.

[0339] In a condensed ring compound according to one embodiment of the present invention, the oscillator strength f in the stable structure of the adiabatic first excited singlet state (S1) is not particularly limited, but may be 0.22 or higher. Additionally, the oscillator strength f may be 0.3 or higher. Furthermore, the oscillator strength f may be 0.4 or higher, or 0.5 or higher. It is believed that a higher fluorescence emission intensity can be obtained within the above ranges. Additionally, the theoretical upper limit of the oscillator strength f is the number of electrons contained in the molecule. The upper limit of the oscillator strength f may be, for example, 2 or 3, but the upper limit of the oscillator strength f is not particularly limited to these.

[0340] In a condensed ring compound according to one embodiment of the present invention, the rearrangement energy may be 0.12 eV or less. Additionally, the rearrangement energy may be 0.1 eV or less, and for example, 0.08 eV or less (lower limit 0 eV). It is believed that within the above range, the spectral width of the luminescence is narrower and luminescence of high color purity can be obtained.

[0341] The fluorescence peak, oscillator intensity f, and relocation energy, which can be obtained by converting the above HOMO, LUMO, and adiabatic S1 excitation energies into optical wavelengths, can be calculated using Density Functional Theory (DFT) and Gaussian 16 (Gaussian Inc.) as the calculation software. Additionally, detailed information on each calculation method is described in the examples.

[0342] The nitrogen-containing condensed ring compound according to the present invention can satisfy all of the following conditions (i) to (iv).

[0343] <Condition (i)>

[0344] ΔΔE ST > ΔE ST2 + ΔE' TT

[0345] <Condition (ii)>

[0346] 0 eV < ΔE ST2 + ΔE' TT ≤ 1.0 eV

[0347] <Condition (iii)>

[0348] 0 eV < ΔE' TT ≤ 0.15 eV

[0349] <Condition (iv)>

[0350] ΔE ST2 > 0 eV

[0351] Under the above conditions (i) to (iv),

[0352] E ST (eV) represents the value of the difference between the lowest singlet excitation energy (eV) calculated for the S1 equilibrium structure and the lowest triplet excitation energy (eV) calculated for the T1 equilibrium structure;

[0353] ΔE ST2 (eV) represents the value of the difference between the lowest singlet excitation energy (eV) calculated for the S1 equilibrium structure and the second lowest triplet excitation energy (eV) calculated for the T2 equilibrium structure;

[0354] ΔE' TT (eV) represents the value of the difference between the second lowest triplet excitation energy (eV) calculated for a T2 equilibrium structure and the lowest triplet excitation energy (eV) calculated for a T2 equilibrium structure.

[0355] Here, S1 equilibrium structure, T1 equilibrium structure, and T2 equilibrium structure refer to the structures that a molecule takes when it reaches each excited state, and represent the structure with the lowest energy for each state, that is, the most stable structure.

[0356] Here, the above conditions (i) to (iv) can be obtained as follows.

[0357] Time-dependent density functional theory (TDDFT), utilizing the PBE0 function and the def2-SVP basis set from the Tamm-Dancoff approximation, was used for structure optimization and energy calculations for the T1, T2, and S1 states. By optimizing the structures, the equilibrium structures of the T1, T2, and S1 states were determined, and the lowest triplet excitation energy for the T1 equilibrium structure, the lowest triplet excitation energy and the second lowest triplet excitation energy for the T2 equilibrium structure, and the lowest singlet excitation energy for the S1 equilibrium structure were calculated. The Q-Chem program was used for the calculations.

[0358] (Table 1) Calculation method for the above conditions (i) to (iv)

[0359] Calculation program Q-Chem program Calculation method S1, T1, and T2 structure optimization and energy calculation by time-dependent density functional theory based on the Tamm-Dancoff approximation using the PBE0 function basis set Def2-SVP basis set

[0360] The inventors have discovered that a compound satisfying all of the above conditions (i) to (iv) can increase the efficiency of an organic electroluminescent device containing it. In a previous application, the applicant reported that a compound satisfying all of the above conditions (i) to (iv) has TADF characteristics, and that an improvement in efficiency can be realized through these TADF characteristics (Korean Patent Application No. 10-2019-0107649). For the nitrogen-containing condensed ring compound of the present invention, satisfying all of the above conditions (i) to (iv) can also significantly increase the efficiency of an organic electroluminescent device containing it. Accordingly, as an embodiment of the present invention, a nitrogen-containing condensed ring compound having a structure represented by the above formula (1) and satisfying all of the above conditions (i) to (iv) can be cited. In addition, as an embodiment of the present invention, a nitrogen-containing condensed ring compound having a structure represented by Formula (2) or Formula (3) and satisfying all of conditions (i) to (iv) may be provided. In this case, at least one of n5 to n8 in Formula (2) is 3 or more, or R 5 to R 8 At least one of them may be an unsubstituted branched alkyl group having 4 to 15 carbon atoms. Or at least one of n5, n7, n9, and n10 of the above formula (3) may be 3 or more, or R 5 , R 7 , R 9 and R 10 At least one of them may be an unsubstituted branched alkyl group having 4 to 15 carbon atoms. A specific embodiment of the present invention may be a nitrogen-containing condensed ring compound that satisfies all of conditions (i) to (iv), wherein the structure represented by formula (1), formula (2), or formula (3) is represented by one of formulas (3-1) to (3-9) (a structure represented by a formula selected from the group consisting of formulas (3-1) to (3-9).

[0361] In addition, as an embodiment of the organic electroluminescent device material described below, a nitrogen-containing condensed ring compound has a structure represented by the above formula (1) and satisfies all of the above conditions (i) to (iv).

[0362] The solubility of the nitrogen-containing condensed ring compound in mesitylene according to one embodiment of the present invention is not particularly limited, but the solubility may be 0.3 g / L or higher. Additionally, the solubility may be 0.5 g / L or higher, and may be 1.0 g / L or higher. Within this range, the luminescence color purity is further improved. The reason for this is presumed to be as follows. As a result of suppressing aggregation between compound molecules and improving the solubility of the compound molecules themselves, thereby improving the degree of purification, the luminescence color purity and device lifespan are improved. Furthermore, since aggregation between compound molecules is unlikely to occur, even when the amount added is increased, a decrease in color purity is unlikely to occur, and luminescence with high color purity is realized. Additionally, the solubility of the nitrogen-containing condensed ring compound in mesitylene according to one embodiment of the present invention is not particularly limited, but the solubility may be 100 g / L or lower. Additionally, the solubility may be 50 g / L or lower, and for example, 30 g / L or lower.

[0363] As one embodiment of the organic electroluminescent device material described below, a nitrogen-containing condensed ring compound may be cited as an organic electroluminescent device material having a solubility in mesitylene of 1.0 g / L or more.

[0364] A nitrogen-containing condensed ring compound according to one embodiment of the present invention is specifically exemplified below. However, the present invention is not limited to these specific examples.

[0365]

[0366]

[0367]

[0368]

[0369]

[0370]

[0371]

[0372]

[0373]

[0374]

[0375]

[0376]

[0377]

[0378]

[0379]

[0380] ８６　　　　　　　　　　　　　　８７

[0381]

[0382] ８８　　　　　　　　　　　　　　　８９

[0383]

[0384] ９０　　　　　　　　　　　　　９１

[0385]

[0386] ９２　　　　　　　　　　　　９３

[0387]

[0388] ９４　　　　　　　　　　　９５　　　　　　　　　　　９６

[0389]

[0390] ９７　　　　　　　　　　　９８

[0391]

[0392] ９９　　　　　　　　　　　　　　１００

[0393]

[0394] １０１　　　　　　　　　　　１０２

[0395]

[0396] １０３　　　　　　　　　　１０４

[0397] １０５　　　　　　　　　　１０６　　　　　　　　　　１０７

[0398] １０８　　　　　　　　　　１０９　　　　　　　　　　　１１０

[0399]

[0400] １１１　　　　　　　　　　　　　　１１２

[0401] １１３

[0402]

[0403] １１４　　　　　　　　　１１５　　　　　　　　　１１６

[0404]

[0405] １１７　　　　　　　　　　　　　　１１８

[0406]

[0407] １１９　　　　　　　　　　　　　　　１２０

[0408]

[0409] １２１　　　　　　　　　　１２２　　　　　　　　　　　１２３

[0410] １２４　　　　　　　　　　　１２５　　　　　　　　　　　　１２６

[0411]

[0412] １２７　　　　　　　　　　　　１２８　　　　　　　　　　１２９

[0413]

[0414] １３０　　　　　　　　　　　１３１　　　　　　　　　　　　１３２

[0415]

[0416] １３３　　　　　　　　　　　１３４　　　　　　　　　　１３５

[0417]

[0418] １３６　　　　　　　　　１３７　　　　　　　　　　　　１３８

[0419]

[0420] １３９　　　　　　　　　１４０　　　　　　　　　　１４１

[0421]

[0422] １４２　　　　　　　　　１４３　　　　　　　　　　　１４４

[0423]

[0424] １４５　　　　　　　　　１４６

[0425]

[0426] １４７　　　　　　　　　　　１４８

[0427]

[0428] １４９　　　　　　　　　　　　１５０

[0429]

[0430] １５１　　　　　　　　　　　１５２　　　　　　　　　　１５３

[0431]

[0432] １５４　　　　　　　　　１５５　　　　　　　　　　　　１５６

[0433]

[0434] １５７　　　　　　　　　　　　１５８

[0435]

[0436] １５９　　　　　　　　　　　　１６０

[0437]

[0438] １６１　　　　　　　　　１６２　　　　　　　　　１６３

[0439]

[0440] １６４　　　　　　　　　　　１６５　　　　　　　　１６６

[0441]

[0442] １６７　　　　　　　１６８　　　　　　　　　　１６９

[0443] １７０　　　　　　　　　　　１７１　　　　　　　　　　１７２

[0444] １７３　　　　　　　　　　１７４　　　　　　　　　　　１７５

[0445]

[0446] １７６　　　　　　　　　１７７

[0447]

[0448] １７８　　　　　　　　　　１７９

[0449]

[0450] １８０　　　　　　　　　　１８１

[0451]

[0452] １８２　　　　　　　　　　　　１８３

[0453]

[0454] １８４　　　　　　　　　　１８５

[0455]

[0456] １８６　　　　　　　　　１８７

[0457]

[0458] １８８　　　　　　　　　　　１８９

[0459]

[0460] １９０　　　　　　　　　　　１９１

[0461] １９２　　　　　　　　　　１９３

[0462]

[0463] １９４　　　　　　　　　　１９５

[0464]

[0465] １９６　　　　　　　　　　　　　　　　　　１９７

[0466]

[0467] １９８　　　　　　　　　　　　　　　　　　　１９９

[0468]

[0469] ２００　　　　　　　　　　　　　　　　 　２０１

[0470]

[0471] ２０２　　　　　　　　　　　　　　　　　２０３

[0472]

[0473] ２０４　　　　　　　　　　　　　　　　　２０５

[0474]

[0475] ２０６　　　　　　　　　　　　　　　　　　　２０７

[0476]

[0477] ２０８　　　　　　　　　　　　　　　　　　　２０９

[0478]

[0479] ２１０　　　　　　　　　　　　　　　　２１１

[0480]

[0481] ２１２　　　　　　　　　　　　　　　　　２１３

[0482]

[0483] ２１４　　　　　　　　　　　　　　　　２１５

[0484]

[0485] ２１６　　　　　　　　　　　　　　　２１７

[0486]

[0487] ２１８　　　　　　　　　２１９　　　　　　　２２０　　　　　２２１

[0488]

[0489] ２２２　　　　　　　　２２３　　　　　　　　２２４　　　　　　２２５

[0490]

[0491] ２２６　　　　　　　　　２２７　　　　　　　　２２８

[0492]

[0493] ２２９　　　　　　　　２３０　　　　　　　２３１

[0494]

[0495] ２３２　　　　　　　　　２３３

[0496]

[0497] ２３４　　　　　　　　２３５　　　　　　　２３６　　　　　　　２３７

[0498]

[0499] ２３８　　　　　　　　　　　　２３９

[0500] ２４０　　　　　　　　　　　　　２４１　　　　　　　　　　　２４２

[0501]

[0502] ２４３　　　　　　　　　　　２４４　　　　　　　　　　　　　２４５

[0503]

[0504] ２４６　　　　　　　　　　　　　２４７　　　　　　　　　　２４８

[0505]

[0506] ２５２　　　　　　　　　　２５３　　　　　　　　　　　　２５４

[0507] ２５５　　　　　　　　　　２５６　　　　　　　　　　　　２５７

[0508]

[0509] ２５８　　　　　　　　　　　　２５９　　　　　　　　　　２６０

[0510] ２６１　　　　　　　　　　　　２６２　　　　　　　　　　２６３

[0511]

[0512]

[0513]

[0514] ２７０　　　　　　　　　　　　　　　　　　２７１

[0515]

[0516] ２７２　　　　　　　　　　２７３　　　　　　　　　　　２７４

[0517]

[0518]

[0519] ２７８　　　　　　　　　　２７９　　　　　　　　　　２８０

[0520]

[0521] ２８１　　　　　　　　　２８２　　　　　　　　　　　　２８３

[0522]

[0523] ２８４　　　　　　　　　　２８５　　　　　　　　　　　　２８６

[0524]

[0525] ２８７　　　　　　　　　　　２８８　　　　　　　　　　　　２８９

[0526]

[0527] ２９０　　　　　　　　　　　２９１　　　　　　　　　　　２９２

[0528]

[0529] ２９３　　　　　　　　　　　２９４　　　　　　　　　　　２９５

[0530]

[0531] ２９６　　　　　　　　　　　２９７　　　　　　　　　　２９８

[0532]

[0533] ２９９　　　　　　　　　　　３００　　　　　　　　　　　３０１

[0534] ３０２　　　　　　　　　 　　３０３　　　　　　　　　　　　３０４

[0535]

[0536] ３０５　　　　　　　　　　３０６　　　　　　　　　　　３０７

[0537]

[0538] ３０８　　　　　　　　　３０９　　　　　　　　　　３１０

[0539]

[0540] ３１１　　　　　　　　３１２　　　　　　　　　　３１３

[0541]

[0542] ３１４　　　　　　　　　３１５　　　　　　　　　　　３１６

[0543]

[0544] ３１７

[0545] Examples of nitrogen-containing condensed ring compounds include the above compounds 1 to 3, 5 to 10, 12 to 14, 18, 19, 65, 66, 71, 75, 76, 79 to 81, 84, 85, 89, 114, 156, 160, 172, 194, and 195. Examples of nitrogen-containing condensed ring compounds include the above compounds 6, 7, 10, 12 to 14, 18, 89, 114, 156, 160, 172, 194, and 195. Examples of nitrogen-containing condensed ring compounds include 6, 7, 10, 12 to 14, 18, 114, and 195. Examples of nitrogen-containing condensed ring compounds include 6, 7, 10, 12 to 14, and 114. Examples of nitrogen-containing condensed ring compounds include the above compounds 7, 10, 12 to 14, and 114.

[0546] The method for synthesizing a nitrogen-containing condensed ring compound according to the present invention is not particularly limited and can be synthesized based on known synthesis methods. More specifically, it can be synthesized using the method described in the examples or in accordance with the method described in the examples. For example, it can be synthesized by changing the raw materials or reaction conditions, adding or excluding some steps in the order of the method described in the examples, or by appropriately combining known synthesis methods.

[0547] The method for confirming the structure of a nitrogen-containing condensed ring compound according to the present invention is not particularly limited. The structure of a nitrogen-containing condensed ring compound according to the present invention can be confirmed by, for example, known methods (e.g., NMR, LC-MS, etc.).

[0548] <Fluorescent Emitting Agent>

[0549] Another embodiment of the present invention relates to a fluorescent emitting agent comprising the above-mentioned nitrogen-containing condensed ring compound and used in combination with a phosphorescent complex described below. By using the fluorescent emitting agent in combination with the phosphorescent complex, the luminous efficiency and device lifespan are significantly improved. The reason for this is presumed to be as follows. The phosphorescent complex transfers energy to the above-mentioned nitrogen-containing condensed ring compound through the FRET mechanism (Fluorescence Resonance Energy Transfer). As a result, high-efficiency energy transfer from the phosphorescent complex to the nitrogen-containing condensed ring compound occurs.

[0550] The fluorescent emitting agent according to the present invention can realize luminescence in which the peak wavelength of the emission spectrum is within the blue wavelength region.

[0551] In addition, the details of the phosphorescent complex used together are as described below. Also, the fluorescent emitting agent can be used together with the host material described below. The details of the host material used together are as described below.

[0552] <Materials for Organic Electroluminescent Devices>

[0553] Another embodiment of the present invention relates to a material for an organic electroluminescent device comprising the above-mentioned nitrogen-containing condensed ring compound. The material may be a material for a light-emitting layer.

[0554] A material for an organic electroluminescent device according to one embodiment of the present invention may include the nitrogen-containing condensed ring compound and other materials used in the organic electroluminescent device. Other materials used in the organic electroluminescent device are not particularly limited but may be phosphorescent compounds or host materials. They may also be phosphorescent complexes and host materials. Here, the nitrogen-containing condensed ring compound may be used as a dopant material, and the phosphorescent complex may be used as an auxiliary dopant material. By using both the nitrogen-containing condensed ring compound and the phosphorescent complex or host material (or the phosphorescent complex and host material), the luminous efficiency and device lifespan are significantly improved. The reason for this is presumed to be as follows. When the material for the organic electroluminescent device contains a host material, the phosphorescent complex receives energy from the host material. The phosphorescent complex then transfers energy to the nitrogen-containing condensed ring compound through the Fluorescence Resonance Energy Transfer (FRET) mechanism. As a result, high-efficiency energy transfer occurs from the phosphorescent complex to the nitrogen-containing condensed ring compound. In addition, other materials used in organic electroluminescent devices may be other known materials in the field.

[0555] The content of the nitrogen-containing condensed ring compound relative to the total mass of the organic electroluminescent device material (particularly the material for the emissive layer) is not particularly limited, but may be 0.05 mass% or more. Additionally, the content may be 0.1 mass% or more, or 0.2 mass% or more. Within this range, an organic electroluminescent device with excellent luminescence color purity and high luminescence efficiency can be obtained. Furthermore, the content of the nitrogen-containing condensed ring compound relative to the total mass of the organic electroluminescent device material (particularly the material for the emissive layer) is not particularly limited, but may be 50 mass% or less. Additionally, the content may be 30 mass% or less, or 25 mass% or less. Within this range, an organic electroluminescent device with excellent luminescence color purity and high luminescence efficiency can be obtained. Furthermore, the content of the nitrogen-containing condensed ring compound according to one embodiment relative to the total mass of the emissive layer within the emissive layer of the organic electroluminescent device described below is also as above.

[0556] (Phosphorescent complex)

[0557] A material for an organic electroluminescent device according to one embodiment of the present invention may further include a phosphorescent complex in addition to the nitrogen-containing condensed ring compound. By including the phosphorescent complex, the luminous efficiency and device lifespan are significantly improved. It is presumed that this is because, as explained in the aforementioned fluorescent light-emitting agent, high-efficiency energy transfer from the phosphorescent complex to the nitrogen-containing condensed ring compound is possible.

[0558] The phosphorescent complex is not particularly limited, but may be a metal complex in terms of luminous efficiency. In the same regard, it may be a platinum complex or a palladium complex, or it may be a platinum complex. Accordingly, in the material for an organic electroluminescent device according to one embodiment of the present invention, for example, the phosphorescent complex is a platinum complex.

[0559] Phosphorescent complexes are not particularly limited, but compounds having the structure of the following formula (4) can be given as examples in terms of luminescence color purity and luminescence efficiency.

[0560]

[0561] In the above formula (4), M is a metal ion with a coordination number of 4, and

[0562] R 41 , R 42 , R 43 and R 44 are independently substituted or unsubstituted hydrocarbon groups or substituted or unsubstituted heterogroups, and

[0563] L 41 is R 41 and R 42 It is a connector that connects,

[0564] L 42 is R 42 and R 43 It is a connector that connects,

[0565] L 43 is R 43 and R 44 It is a connector that connects.

[0566] In the above equation (4), a hydrocarbon group represents a group derived from one or more hydrocarbon groups. When a hydrocarbon group contains two or more hydrocarbon groups, some or all of these groups may be connected by single bonds or condensed. Additionally, when a hydrocarbon group contains two or more hydrocarbon groups, one atom may serve as a ring-forming atom of any of these groups.

[0567] In the above equation (4), the heterocyclic group is the same as the monovalent heterocyclic group described in the above equation (1), except for the difference in the valence.

[0568] The substituents that substitute for the hydrocarbon group or heterogroup in the above formula (4) are not particularly limited, but substituents that substitute for the groups (c) to (g) of the above formula (1) may be used.

[0569] In the above equation (4), M can be a platinum (Pt) ion, a palladium (Pd) ion, and, for example, a platinum (Pt) ion.

[0570] For the phosphorescent complex, known compounds may be used. For example, the platinum complex described in Tyler Fleetham et al. “Effcient “Pure” Blue OLEDs Employing Tetradentate Pt Complexes with a Narrow Spectral Bandwidth”, Advanced Materials, 2014, 26, 7116-7121, the platinum complex described in European Patent Application Publication No. 3670520, the platinum complex and palladium complex described in Japanese Patent Application Publication No. 2019-029500, and the platinum complex described in U.S. Patent Application Publication No. 2015 / 0162552 may be used.

[0571] A phosphorescent complex according to one embodiment of the present invention is specifically exemplified below. However, the present invention is not limited to these specific examples.

[0572]

[0573]

[0574]

[0575]

[0576]

[0577]

[0578]

[0579] ​

[0580]

[0581]

[0582]

[0583]

[0584]

[0585] P119

[0586] The content of the phosphorescent complex relative to the total mass of the organic electroluminescent device material (particularly the material for the emissive layer) is not particularly limited, but may be 0.1 mass% or more, or 0.2 mass% or more. Additionally, the content may be 0.5 mass% or more, or 1 mass% or more. The content may be, for example, 3 mass% or more, or 5 mass% or more. Within this range, an organic electroluminescent device with excellent luminescence color purity and high luminescence efficiency can be obtained. Furthermore, the content of the phosphorescent complex relative to the total mass of the organic electroluminescent device material (particularly the material for the emissive layer) is not particularly limited, but may be 50 mass% or less. Additionally, the content may be 40 mass% or less, or 30 mass% or less. Within this range, an organic electroluminescent device with excellent luminescence color purity and high luminescence efficiency can be obtained. In addition, the content of a phosphorescent complex according to one embodiment relative to the total mass of the light-emitting layer within the light-emitting layer of the organic electroluminescent device described below is also as above.

[0587] When a material for an organic electroluminescent device (particularly a material for a light-emitting layer) includes a phosphorescent complex, the content thereof may be 100 parts by mass or more per 100 parts by mass of the nitrogen-containing condensed ring compound. Additionally, the content may be 150 parts by mass or more, or 200 parts by mass or more, per 100 parts by mass of the nitrogen-containing condensed ring compound. Within this range, an organic electroluminescent device with excellent luminescence color purity and high luminescence efficiency can be obtained. Furthermore, the content of the phosphorescent complex is not particularly limited, but may be 10,000 parts by mass or less per 100 parts by mass of the nitrogen-containing condensed ring compound. Additionally, the content may be 7,500 parts by mass or less, or 5,000 parts by mass or less, per 100 parts by mass of the nitrogen-containing condensed ring compound. Within this range, an organic electroluminescent device with excellent luminescence color purity and high luminescence efficiency can be obtained. In addition, the content (parts by mass) of a phosphorescent complex according to one embodiment with respect to 100 parts by mass of the nitrogen-containing condensed ring compound in the light-emitting layer of the organic electroluminescent device described below is also as above.

[0588] (Host ingredients)

[0589] A material for an organic electroluminescent device according to one embodiment of the present invention may further include a host material in addition to the nitrogen-containing condensed ring compound. By using the nitrogen-containing condensed ring compound as a dopant material and combining it with a host material, excellent luminous efficiency and device lifespan can be realized in an organic electroluminescent device.

[0590] The host material is not particularly limited and known host materials may be used. Examples of host materials include compounds having a carbazole ring structure (except for compounds represented by the general formula (1) above), compounds having a ring structure in which one or more of the cyclic carbon atoms of the carbazole ring are substituted for nitrogen atoms (except for compounds represented by the general formula (1) above and compounds having the carbazole ring structure above), or compounds having a triazine ring structure (except for compounds represented by the general formula (1) above, compounds having the carbazole ring structure above, and compounds having a ring structure in which one or more of the cyclic carbon atoms of the carbazole ring are substituted for nitrogen atoms above). Among these, it may be a compound having a carbazole ring structure. By using such a compound as a host material, efficient energy transfer within the light-emitting layer can be promoted. In addition, the balance of charge mobility between electrons and holes can be further improved. In addition, among these compounds, in the carbazole ring structure, the ring structure formed by substituting one or more cyclic carbon atoms of the carbazole ring with nitrogen atoms, and the triazine ring structure, the hydrogen atoms bonded to the cyclic atoms constituting these rings may be substituted by other atoms or substituents. Also, two or more such substituents may form the ring structure.

[0591] The compound having the above-mentioned carbazole ring structure or the compound having a ring structure in which one or more of the cyclic carbon atoms of the above-mentioned carbazole ring are substituted for nitrogen atoms is not particularly limited, but may be a compound having a structure represented by the following formula (5).

[0592]

[0593] In the above equation (5),

[0594] Z 51 is CH, CR 51 or N and,

[0595] Z 52 is CH, CR 52 or N and,

[0596] Z 53 is CH, CR 53 or N and,

[0597] Z 54 is CH, CR 54 or N and,

[0598] Z 55 is CH, CR 55 or N and,

[0599] Z 56 is CH, CR 56 or N and,

[0600] Z 57 is CH, CR 57 or N and,

[0601] Z 58 is CH, CR 58 or N and,

[0602] R 51 to R 58 is one of the methods (5a) to (5h) independently of each other, and

[0603] (5a) Cyanogi,

[0604] (5b) Substituted or unsubstituted alkyl groups having 1 to 20 carbon atoms,

[0605] (5c) Substituted or unsubstituted alkoxy groups having 1 to 20 carbon atoms,

[0606] (5d) Substituted or unsubstituted aryl amino groups having 6 to 20 carbon atoms,

[0607] (5e) Substituted or unsubstituted phosphoryl group (-POH2 group),

[0608] (5f) Substituted or unsubstituted silyl group (-SiH3 group),

[0609] (5g) Substituted or unsubstituted monovalent aromatic hydrocarbon group,

[0610] (5h) Substituted or unsubstituted monovalent heterocyclic,

[0611] Ar 51is a group comprising at least one of an aromatic hydrocarbon group and a heterocyclic group, and

[0612] m is 1, 2, 3, 4, 5, or 6, and

[0613] Here, the above R 51 and the above R 52 , above R 52 and the above R 53 , above R 53 and the above R 54 , above R 55 and the above R 56 , above R 56 and the above R 57 or the above R 57 and the above R 58 Each can form an aliphatic hydrocarbon ring, an aromatic hydrocarbon ring, or a heterocyclic ring containing a carbon atom bonded to it.

[0614] The descriptions of the elements (5b), (5c), (5d), (5g), and (5f) in the above equation (5) are the same as the descriptions of the elements (c), (d), (e), (f), and (g) in the above equation (1), respectively.

[0615] Also Ar 51 The aromatic hydrocarbon group is the same as the monovalent aromatic hydrocarbon group described in the above (f) of the above formula (1), except that the valence is different.

[0616] And Ar 51 In this case, the heterocyclic group is the same as the monovalent heterocyclic group described in the above (g) of the above equation (1), except that the valence is different.

[0617] Z in the above equation (5) 51 To Z 58 None of them are N, or only one can be N. Also, Z 51 To Z 58 Not everyone may be N.

[0618] In the above formula (5), if the groups of (5c) to (5h) are substituted, the substituents that substitute these groups are not particularly limited. For example, they may be the groups of (5a) to (5h). Specific examples of substituents substituting such groups are not particularly limited, but include a cyano group, an unsubstituted alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms substituted with a monovalent aromatic hydrocarbon having 6 to 30 carbon atoms further substituted with an unsubstituted alkenyl group having 2 to 30 carbon atoms, a substituted or unsubstituted aryl amino group having 6 to 20 carbon atoms, an unsubstituted monovalent aromatic hydrocarbon having 6 to 30 carbon atoms, a monovalent aromatic hydrocarbon having 6 to 30 carbon atoms substituted with a cyano group, a monovalent aromatic hydrocarbon having 6 to 30 carbon atoms substituted with an unsubstituted alkenyl group having 2 to 30 carbon atoms, a monovalent aromatic hydrocarbon having 6 to 30 carbon atoms substituted with an unsubstituted aryl amino group having 6 to 20 carbon atoms, and unsubstituted Examples include monovalent heterocyclic groups with 3 to 30 cyclic atoms, monovalent heterocyclic groups with 3 to 30 cyclic atoms substituted with unsubstituted monovalent aromatic hydrocarbon groups with 6 to 30 carbon atoms.

[0619] In the above equation (5), Ar 51 The group is not particularly limited to at least one of an aromatic hydrocarbon group and a heterocyclic group. Examples include a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted heterocyclic group, a group in which one or more substituted or unsubstituted aromatic hydrocarbons and one or more substituted or unsubstituted heterocyclic groups are joined through a single bond, two or more substituted or unsubstituted aromatic hydrocarbon groups, or a group in which a substituted or unsubstituted heterocyclic group is joined through a linker other than these groups.

[0620] Here, in groups in which two or more substituted or unsubstituted aromatic hydrocarbon groups or substituted or unsubstituted heterocyclic groups are joined through a linker other than these groups, the linker is not particularly limited. Specific examples include Si groups, N groups, P=O groups, S(=O)=O groups, C=O groups, etc.

[0621] In the above equation (5), Ar 51 In the case where the group constituting the group is a substituted group, the substituent substituting such a group is not particularly limited. For example, it may be the group of (5a) to (5h) above. Specific examples of substituents substituting such a group are not particularly limited, but may include a cyano group, an unsubstituted alkyl group having 1 to 20 carbon atoms, a monovalent heterocyclic group having 3 to 30 cyclic atoms substituted with an unsubstituted alkyl group having 1 to 20 carbon atoms, etc.

[0622] Here, the substituent of the group of (5c) to (5h) above or Ar 51 Among the substituents of the groups constituting the group, the alkyl group having 1 to 20 carbon atoms, the alkoxy group having 1 to 20 carbon atoms, the aryl amino group having 6 to 20 carbon atoms, the monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms, and the monovalent heterocyclic group having 3 to 30 cyclic atoms are each described as such groups in the groups of (c), (d), (e), (f), and (g) of the above formula (1).

[0623] Also, the substituent of the group of (5c) to (5h) above, Ar 51The alkenyl group having 2 to 30 carbon atoms as a substituent of the group constituting the group is not particularly limited and may be straight, branched, or cyclic. Specific examples of alkenyl groups are not particularly limited, but examples include vinyl groups, 2-propenyl groups, 2-butenyl groups, 3-butenyl groups, 1-methyl-2-propenyl groups, 2-methyl-2-propenyl groups, 2-pentenyl groups, 3-pentenyl groups, 4-pentenyl groups, 1-methyl-2-butenyl groups, 2-methyl-2-butenyl groups, 3-methyl-2-butenyl groups, 1-methyl-3-butenyl groups, 2-methyl-3-butenyl groups, 3-methyl-3-butenyl groups, 1,1-dimethyl-2-propenyl groups, 1,2-dimethyl-2-propenyl groups, 1-ethyl-2-propenyl groups, etc.

[0624] m can be 1, 2, 3 or 4, or 2.

[0625] The following specifically exemplifies a compound having a carbazole ring structure, which is a host material according to one embodiment of the present invention, and a compound having a ring structure in which one or more of the ring-forming carbon atoms of the carbazole ring are substituted for nitrogen atoms. However, the present invention is not limited to these specific examples.

[0626]

[0627]

[0628]

[0629]

[0630]

[0631]

[0632]

[0633] From this, an organic electroluminescent device material according to one embodiment of the present invention may be an organic electroluminescent device material comprising the nitrogen-containing condensed ring compound, the phosphorescent complex, and a host material, wherein the host material comprises a compound having a structure represented by Formula (5). Furthermore, an organic electroluminescent device described below may be an organic electroluminescent device comprising the fluorescent emitting agent, or the nitrogen-containing condensed ring compound and a host material, wherein the host material comprises a compound having a structure represented by Formula (5).

[0634] The compound having the above triazine ring structure is not particularly limited, but may be a compound having a structure represented by the following formula (6).

[0635]

[0636] In the above equation (6)

[0637] Ar 61 or Ar 63 They are independently substituted or unsubstituted monovalent aromatic hydrocarbon groups or substituted or unsubstituted monovalent heterocyclic groups.

[0638] In the above formula (6), the substituted or unsubstituted monovalent aromatic hydrocarbon group is the same as the description of the group (f) in the above formula (1). Also, the substituted or unsubstituted monovalent heterocyclic group is the same as the description of the group (g) in the above formula (1).

[0639] The substituents substituting the monovalent aromatic hydrocarbon group or the monovalent heterocyclic group in the above formula (6) are not particularly limited, but may be those listed as substituents substituting the groups (c) to (g) of the above formula (1). Additionally, they may be silyl groups substituted with unsubstituted monovalent aromatic hydrocarbon groups. Furthermore, the unsubstituted monovalent aromatic hydrocarbon group is the same as the description of the unsubstituted group that can be listed as the group of (f).

[0640] Among compounds having a triazine ring structure, it may be a compound containing a silyl group (a compound having a triazine ring structure containing a silyl group).

[0641] Additionally, a compound having a triazine ring structure can be used in combination with a compound having a carbazole ring structure or a compound having a ring structure in which one or more of the ring-forming carbon atoms of the carbazole ring are substituted for nitrogen atoms.

[0642] A compound having a triazine ring structure, which serves as a host material according to one embodiment of the present invention, is specifically exemplified below. However, the present invention is not limited to these specific examples.

[0643]

[0644] From this, an organic electroluminescent device material according to one embodiment of the present invention may be an organic electroluminescent device material comprising the nitrogen-containing condensed ring compound, the phosphorescent complex, and a host material, wherein the host material comprises a compound having a structure represented by Formula (6). Furthermore, an organic electroluminescent device material according to another embodiment of the present invention may be an organic electroluminescent device material comprising the nitrogen-containing condensed ring compound, the phosphorescent complex, and a host material, wherein the host material comprises a compound having a structure represented by Formula (5) and a compound having a structure represented by Formula (6). Additionally, an organic electroluminescent device described below may be an organic electroluminescent device comprising the fluorescent emitting agent or the nitrogen-containing condensed ring compound and a host material, wherein the host material comprises a compound having a structure represented by Formula (6). And another embodiment of the organic electroluminescent device may be an organic electroluminescent device comprising the fluorescent emitting agent or the nitrogen-containing condensed ring compound and a host material, wherein the host material comprises a compound having a structure represented by Formula (5) and a compound having a structure represented by Formula (6).

[0645] The content of the host material relative to the total mass of the organic electroluminescent device material (particularly the material for the emissive layer) is not particularly limited, but may be 5 mass% or more. Additionally, the content may be 10 mass% or more, or 20 mass% or more. Within this range, an organic electroluminescent device with excellent luminescence color purity and high luminescence efficiency can be obtained. Furthermore, the content of the host material relative to the total mass of the organic electroluminescent device material (particularly the material for the emissive layer) is not particularly limited, but may be 99 mass% or less. Additionally, the content may be 98 mass% or less, or 95 mass% or less. Within this range, an organic electroluminescent device with excellent luminescence color purity and high luminescence efficiency can be obtained. Furthermore, the content of the host material according to one embodiment relative to the total mass of the emissive layer within the emissive layer of the organic electroluminescent device described below is also as above.

[0646] When a material for an organic electroluminescent device includes a host material, the content thereof may be 1,000 parts by mass or more per 100 parts by mass of the nitrogen-containing condensed ring compound. Additionally, the content may be 2,000 parts by mass or more, or 3,000 parts by mass or more, per 100 parts by mass of the nitrogen-containing condensed ring compound. Within this range, an organic electroluminescent device with excellent luminescence color purity and high luminescence efficiency can be obtained. Furthermore, the content of the host material is not particularly limited, but may be 200,000 parts by mass or less per 100 parts by mass of the nitrogen-containing condensed ring compound. Additionally, the content may be 150,000 parts by mass or less, or 100,000 parts by mass or less, per 100 parts by mass of the nitrogen-containing condensed ring compound. Within this range, an organic electroluminescent device with excellent luminescence color purity and high luminescence efficiency can be obtained. In addition, the content (parts by mass) of a host material according to one embodiment with respect to 100 parts by mass of the nitrogen-containing condensed ring compound in the light-emitting layer of the organic electroluminescent device described below is also as above.

[0647] <Liquid Composition>

[0648] Another embodiment of the present invention relates to a liquid composition comprising the above-mentioned nitrogen-containing heterocyclic compound, the above-mentioned fluorescent emitting agent, or the above-mentioned material for an organic electroluminescent device, and a solvent.

[0649] The solvent is not particularly limited, but may be a solvent having a boiling point at atmospheric pressure (101.3 kPa, 1 Atm) of 100°C or higher and 350°C or lower. The boiling point of the solvent at atmospheric pressure may be 150°C or higher and 320°C or lower, or 180°C or higher and 300°C or lower. When the boiling point of the solvent at atmospheric pressure is within the above range, the film-forming properties and processability in wet film-forming methods, particularly inkjet methods, are improved. The solvent having a boiling point at atmospheric pressure of 100°C or higher and 350°C or lower is not particularly limited, and known solvents may be appropriately employed. Solvents having a boiling point at atmospheric pressure of 100°C or higher and 350°C or lower are specifically exemplified below, but the present invention is not limited to these specific examples. Examples of hydrocarbon solvents include octane, nonane, decane, undecane, dodecane, etc. Examples of aromatic hydrocarbon solvents include toluene, xylene, ethylbenzene, n-propylbenzene, iso-propylbenzene, n-propylbenzene, mesitylene, n-butylbenzene, sec-butylbenzene, 1-phenylpentane, 2-phenylpentane, 3-phenylpentane, phenylcyclopentane, phenylcyclohexane, 2-ethylbiphenyl, 3-ethylbiphenyl.Examples of ether-based solvents include 1,4-dioxane, 1,2-diethoxyethane, diethyleneglycoldimethylether, diethyleneglycoldiethylether, anisole, ethoxybenzene, 3-methylanisole, and m-dimethoxybenzene. Examples of ketone-based solvents include 2-hexanone, 3-hexanone, cyclohexanone, 2-heptanone, 3-heptanone, 4-heptanone, and cycloheptanone. Examples of ester-based solvents include butyl acetate, butylpropionate, butylbutyrate, propylene carbonate, methylbenzoate, ethylbenzoate, 1-propylbenzoate, and 1-butylbenzoate. Examples of nitrile-based solvents include benzonitrile and 3-methylbenzonitrile. Examples of amide-based solvents include dimethylformamide, dimethylacetamide, and N-methylpyrrolidone. These solvents may be used individually or in combination of two or more.

[0650] In one embodiment of the present invention, the content of the nitrogen-containing heterocyclic compound, the fluorescent emitting agent, or the organic electroluminescent device material in the liquid composition is not particularly limited.

[0651] In one embodiment of the present invention, the liquid composition can be used as a coating solution for forming an organic layer of an organic electroluminescent device. In addition, the liquid composition can be used as a coating solution for forming a light-emitting layer among coating solutions for forming an organic layer.

[0652] <Organic Electroluminescent Device>

[0653] Another embodiment of the present invention relates to an organic electroluminescent device comprising the nitrogen-containing condensed ring compound or the fluorescent emitting agent. Additionally, the organic electroluminescent device may comprise the nitrogen-containing condensed ring compound or the fluorescent emitting agent and the host material. Alternatively, it may comprise the nitrogen-containing condensed ring compound or the fluorescent emitting agent and the phosphorescent complex. In this case, the phosphorescent complex may be a platinum complex.

[0654] Furthermore, another embodiment of the present invention relates to an organic electroluminescent device comprising the above-described organic electroluminescent device material. In addition, in the organic electroluminescent device, the above-described organic electroluminescent device material may further comprise the above-described host material. And in the organic electroluminescent device, the phosphorescent complex included therein may be a platinum complex.

[0655] In an organic electroluminescent device, the host material included therein may be a compound having the carbazole ring structure, a compound having a ring structure formed by substituting one or more of the ring-forming carbon atoms of the carbazole ring with nitrogen atoms, or a compound having the triazine ring structure. Additionally, the host material included therein in an organic electroluminescent device may include a compound having a structure represented by Formula (5). Additionally, the host material included therein in an organic electroluminescent device may include a compound having a structure represented by Formula (6). Furthermore, the host material included therein in an organic electroluminescent device may include a compound having a structure represented by Formula (5) and a compound having a structure represented by Formula (6).

[0656] In addition, the phosphorescent complex included therein in the organic electroluminescent device may be a compound having a structure represented by the formula (4).

[0657] An organic electroluminescent device according to one embodiment of the present invention is not particularly limited, but includes, for example, a first electrode, a second electrode, and a single or multiple organic layers. The second electrode is disposed on the first electrode.

[0658] In this specification, when a part such as a layer, film, region, or plate is described as being "above" or "upper" to another part, this includes not only cases where it is "immediately above" the other part, but also cases where there is another part in between. Conversely, when a part such as a layer, film, region, or plate is described as being "below" or "lower" to another part, this includes not only cases where it is "directly below" the other part, but also cases where there is another part in between. Furthermore, in this application, being "placed above" includes not only the upper surface, but also cases where it is placed on the lower or underside surface.

[0659] An organic electroluminescent device according to one embodiment of the present invention comprises a first electrode, a second electrode, and a single or multiple layers disposed between the first electrode and the second electrode. Herein, the layer comprises at least one organic layer, and at least one of the organic layers comprises the nitrogen-containing condensed ring compound, the fluorescent emitting agent, or the material for the organic electroluminescent device. The organic layer comprising the nitrogen-containing condensed ring compound, the fluorescent emitting agent, or the material for the organic electroluminescent device may comprise a emitting layer. With such an organic electroluminescent device, light emission of high color purity can be realized.

[0660] In this way, the light-emitting layer may include at least one of the above-mentioned nitrogen-containing condensed ring compounds.

[0661] The light-emitting layer may be a single layer made of a single material, or a single layer made of multiple different materials. Additionally, the light-emitting layer may be a multilayer structure having multiple layers made of multiple different materials.

[0662] The light-emitting layer is not particularly limited, but may include, for example, a host material and a dopant material. The nitrogen-containing condensed ring compound and the fluorescent light-emitting agent may be used as a host material or as a dopant material, but may be used as a dopant material.

[0663] From this, one embodiment of the present invention may include an organic electroluminescent device comprising a light-emitting layer, wherein the light-emitting layer comprises the nitrogen-containing condensed ring compound, the fluorescent light-emitting agent, or the organic electroluminescent device material. Additionally, the light-emitting layer may be composed of the organic electroluminescent device material. In terms of the peak wavelength of the emission spectrum, the color purity of the emission, the luminous efficiency, and the device lifespan, the organic electroluminescent device material may include the host material in addition to the nitrogen-containing condensed ring compound. In the same regard, the organic electroluminescent device material may include the phosphorescent complex and the host material in addition to the nitrogen-containing condensed ring compound. Furthermore, the range of the content or content ratio of the nitrogen-containing condensed ring compound, the phosphorescent complex, and the host material in the light-emitting layer according to one embodiment is the same as the content or content ratio according to one embodiment of the organic electroluminescent device material.

[0664] The thickness of the light-emitting layer is not particularly limited, but may be 1 nm or more and 100 nm or less, or 10 nm or more and 50 nm or less.

[0665] The method of forming the light-emitting layer is not particularly limited, but known methods of forming the layer may be used, such as vacuum deposition, spin coating, LB method (Langmuir-Blodgett), inkjet printing, laser printing, and laser thermal imaging (Laser Induced Thermal Imaging, LITI).

[0666] The emission wavelength of an organic electroluminescent device is not particularly limited. The range of the emission wavelength of an organic electroluminescent device according to one embodiment is, for example, the same as the peak wavelength of emission in photoluminescence (PL) of a nitrogen-containing condensed ring compound according to the present invention. Among these, in the specifications of currently commercialized products, in the case of blue emission, light having a peak in the wavelength region of 445 nm or more and 470 nm or less can be emitted, or light having a peak in the wavelength region of 450 nm or more and 470 nm or less can be emitted, or light having a peak in the wavelength region of 450 nm or more and 465 nm or less can be emitted.

[0667] In addition, it is preferable that the Full Width at Half Maximum (FWHM) of the peak of the emission spectrum of the organic electroluminescent device be smaller. Furthermore, the FWHM of the peak of the emission spectrum may be 30 nm or less, or 25 nm or less. It may also be 20 nm or less (above the lower limit of 0 nm).

[0668] Referring to the attached drawings, an organic electroluminescent device according to one embodiment of the present invention will be described in detail as having an additional organic layer other than the light-emitting layer. Additionally, in the description of the drawings, the same reference numerals are assigned to identical elements to omit redundant descriptions. Furthermore, the dimensional ratios in the drawings are exaggerated for convenience of explanation and may differ from the actual ratios.

[0669] FIGS. 1 to 3 are schematic cross-sectional views showing an organic electroluminescent device according to one embodiment of the present invention. However, the structure of the organic electroluminescent device according to the present invention is not limited to the form shown in FIGS. 1 to 3.

[0670] FIG. 1 is a schematic cross-sectional view showing an organic electroluminescent device according to one embodiment of the present invention. An organic electroluminescent device (10) according to one embodiment of the present invention includes a substrate (1), a first electrode (2), a hole transport region (3), a light-emitting layer (4), an electron transport region (5), and a second electrode (6) stacked in sequence.

[0671] FIG. 2 is a schematic cross-sectional view showing an organic electroluminescent device according to another embodiment of the present invention. An organic electroluminescent device (20) according to one embodiment of the present invention comprises a substrate (1), a first electrode (2), a hole transport region (3), a light-emitting layer (4), an electron transport region (5), and a second electrode (6) stacked in sequence. In FIG. 2, the hole transport region (3) includes a hole injection layer (31) and a hole transport layer (32) stacked in sequence. Also in FIG. 2, the electron transport region (5) includes an electron transport layer (52) and an electron injection layer (51) stacked in sequence.

[0672] FIG. 3 is a schematic cross-sectional view showing an organic electroluminescent device according to another embodiment of the present invention. An organic electroluminescent device (30) according to one embodiment of the present invention comprises a substrate (1), a first electrode (2), a hole transport region (3), a light-emitting layer (4), an electron transport region (5), and a second electrode (6) stacked in sequence. In FIG. 3, the hole transport region (3) includes a hole injection layer (31), a hole transport layer (32), and an electron blocking layer (33) stacked in sequence. Also in FIG. 3, the electron transport region (5) includes a hole blocking layer (53), an electron transport layer (52), and an electron injection layer (51) stacked in sequence.

[0673] The substrate, each region, and each layer will be described in detail below.

[0674] (Board (1))

[0675] The organic electroluminescent device (10) may have a substrate (1). The substrate (1) may be a substrate used for general organic electroluminescent devices. For example, the substrate (1) may be a glass substrate, a semiconductor substrate such as a silicon substrate, or a transparent plastic substrate.

[0676] (First electrode (2))

[0677] The first electrode (2) has conductivity. In an organic electroluminescent device according to one embodiment of the present invention, the first electrode (2) may be an anode. Additionally, the first electrode (2) may be a pixel electrode. Furthermore, the first electrode (2) may be a transmissive electrode, a transmissive electrode, or a reflective electrode.

[0678] The material constituting the first electrode (2) is not particularly limited, but may include, for example, a metal alloy or a conductive compound. If the first electrode (2) is a transmissive electrode, the first electrode (2) may include a transparent metal oxide, for example, ITO (indium tin oxide), IZO (indium zinc oxide), ZnO (zinc oxide), ITZO (indium tin zinc oxide), etc. Additionally, if the first electrode (2) is a semi-transmissive electrode or a reflective electrode, the first electrode (2) may include Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF / Ca, LiF / Al, Mo, Ti, or a compound or mixture thereof (for example, a mixture of Ag and Mg).

[0679] The first electrode (2) may be a single layer made of a single material, or a single layer made of a plurality of different materials. In addition, the first electrode (2) may be a multilayer structure having a plurality of layers made of a plurality of different materials.

[0680] The thickness of the first electrode (2) is not particularly limited, but may be 10 nm or more and 1000 nm or less, or 50 nm or more and 300 nm or less.

[0681] (Pure transport area (3))

[0682] A hole transport region (3) is provided on the first electrode (2). The hole transport region (3) includes at least one of a hole injection layer (31), a hole transport layer (32), a hole buffer layer (not shown), and an electron blocking layer (33).

[0683] The hole transport region (3) may be a single layer made of a single material or a single layer made of multiple different materials. Additionally, the hole transport region (3) may be a multilayer structure having multiple layers made of multiple different materials.

[0684] For example, the hole transport region (3) may have a single-layer structure of a hole injection layer (31) or a hole transport layer (32). Also, for example, the hole transport region (3) may have a single-layer structure formed of a hole injection material and a hole transport material. Also, for example, the hole transport region (3) may have a structure of a hole injection layer (31) / hole transport layer (32) stacked sequentially from the first electrode (2). Also, for example, the hole transport region (3) may have a structure of a hole injection layer (31) / hole transport layer (32) / hole buffer layer (not shown). Also, for example, the hole transport region (3) may have a structure of a hole injection layer (31) / hole buffer layer (not shown) stacked sequentially from the first electrode (2). Also, for example, the hole transport region (3) may have a structure of a hole transport layer (32) / hole buffer layer (not shown) stacked sequentially from the first electrode (2). Additionally, for example, the hole transport region (3) may have a structure of a hole injection layer (31) / hole transport layer (32) / electron blocking layer (33) stacked sequentially from the first electrode (2). However, the structure of the hole transport region is not limited to these.

[0685] Each layer constituting the hole injection layer (31) or other hole transport region (3) is not particularly limited, but may include, for example, known hole injection materials. Examples of hole injection materials include phthalocyanine compounds such as copper phthalocyanine, DNTPD (N,N'-diphenyl-N,N'-bis-4-(phenyl-m-tolyl-amino)-phenyl-biphenyl-4,4'-diamine), m-MTDATA (4,4',4"-tris(3-methylphenylphenylamino)triphenylamine), TDATA (4,4',4"-tris(N,N-diphenylamino)triphenylamine), 2-TNATA (4,4',4"-tris{N-(2-naphthyl)-N-phenylamino}-triphenylamine), PEDOT / PSS (poly(3,4-ethylenedioxythiophene) / poly(4-styrenesulfonate)), PANI / DBSA (polyaniline / dodecylbenzenesulfonic acid), PANI / CSA (polyaniline / camphosulfonic acid), Examples include PANI / PSS (polyaniline) / poly(4-styrenesulfonate), NPB (N,N'-di(naphthalene-1-yl)-N,N'-diphenylbenzidine), polyetherketone containing triphenylamine (TPAPEK), 4-isopropyl-4'-methyldiphenyliodniumtetrakis(pentafluorophenyl)borate, HAT-CN (dipyrazino[2,3-f:2',3'-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile), F6-TCNNQ (1,3,4,5,7,8-hexafluorotetracyano-2,6-naphthoquinodimethane).

[0686] In addition, each layer constituting the hole transport layer (32) or other hole transport region (3) is not particularly limited, but may include, for example, known hole transport materials. Hole transport materials include, for example, carbazole derivatives such as N-phenylcarbazole and polyvinyl carbazole, fluorene derivatives, triphenylamine derivatives such as TPD (N,N'-bis(3-methylphenyl)-N,N'-diphenyl-1,1-biphenyl]-4,4'-diamine), TCTA (4,4',4"-tris(N-carbazoleyl), triphenylamine), NPB (N,N'-di(naphthalene-1-yl)-N,N'-diphenylbenzidine), TAPC (4,4'-cyclohexylidenebis[N,N-bis(4-methylphenyl)benzenamine]), HMTPD (4,4'-bisN,N'-(3-tolyl)amino]-3,3'-dimethylbiphenyl), mCP (1,3-bis(N-carbazoleyl)benzene), the following compounds HTM1, HTM2, and HT1. there is.

[0687]

[0688] (n is an integer greater than or equal to 1.)

[0689]

[0690] (n is an integer greater than or equal to 1.)

[0691]

[0692] The hole transport region (3) may further include a charge generating material to improve conductivity in addition to the hole injection material or hole transport material described above. The charge generating material is dispersed uniformly or non-uniformly within the hole transport region (3) or within each layer constituting it. The charge generating material is not particularly limited, but examples include known charge generating materials. Examples of charge generating materials include p-dopants. Examples of p-dopants include quinone derivatives such as TCNQ (tetracyanoquinodimethane) and F4-TCNQ (2,3,5,6-tetrafluorotetracyanoquinodimethane), metal oxides such as tungsten oxide and molybdenum oxide, and cyano group-containing compounds.

[0693] A hole buffer layer (not shown) increases light emission efficiency by compensating for the resonance distance based on the wavelength of light emitted from the light-emitting layer (4). The material included in the hole buffer layer (not shown) is not particularly limited and can use the material used in the hole transport layer. For example, a compound that can be included in the hole transport region (3) as described above can be used.

[0694] The electron blocking layer (33) is a layer that prevents the injection of electrons from the electron transport region (5) into the hole transport region (3). The material included in the electron blocking layer (33) is not particularly limited, and any known material used in the electron blocking layer (33) may be used. For example, a host material included in the above-mentioned light-emitting layer (material for organic electroluminescent devices) may be used, and the above-mentioned compounds H55, H86, H87, etc., which are host materials, may be cited as examples.

[0695] The thickness of the hole transport region (3) is not specifically limited, but may be 1 nm or more and 1000 nm or less, or 10 nm or more and 500 nm or less. Additionally, for each layer constituting the hole transport region (3), the thickness of the hole injection layer (31) is not specifically limited, but may be 3 nm or more and 200 nm or less. The thickness of the hole transport layer (32) is not specifically limited, but may be 3 nm or more and 200 nm or less. The thickness of the electron blocking layer (33) is not specifically limited, but may be 1 nm or more and 100 nm or less. Furthermore, the thickness of the hole buffer layer (not shown) is not specifically limited as long as it is within a range that performs the function of the hole buffer layer without interfering with the function as an organic electroluminescent device. When the thickness of the hole transport region (3), hole injection layer (31), hole transport layer (32), or electron blocking layer (33) satisfies the above range, better hole transport characteristics can be obtained while suppressing the rise in the actual driving voltage.

[0696] The method of forming the film of the hole transport region (3) or each layer constituting it is not particularly limited, but known film forming methods such as vacuum deposition, spin coating, LB method, inkjet printing, laser printing, and laser thermal transfer can be cited.

[0697] (Light-emitting layer (4))

[0698] The light-emitting layer (4) is placed on the hole transport region (3). The details of the light-emitting layer (4) are as described above.

[0699] (Electronic transport area (5))

[0700] The electron transport region (5) is disposed on the light-emitting layer (4). The electron transport region (5) includes at least one of an electron injection layer (51), an electron transport layer (52), and a hole blocking layer (53), but the embodiment is not limited thereto.

[0701] The electron transport region (5) may be a single layer made of a single material or a single layer made of multiple different materials. Additionally, the electron transport region (5) may be a multilayer structure having multiple layers made of multiple different materials. For example, the electron transport region (5) may have a single layer structure of an electron injection layer (51) or an electron transport layer (52). Also, for example, the electron transport region (5) may have a single layer structure made of an electron injection material and an electron transport material. Also, for example, the electron transport region (5) may have a structure of an electron transport layer (52) / electron injection layer (51) stacked sequentially from the light-emitting layer (4). Also, for example, the electron transport region (5) may have a structure of a hole blocking layer (53) / electron transport layer (52) / electron injection layer (51) stacked sequentially from the light-emitting layer (4). However, the structure of the electron transport region (5) is not limited to these.

[0702] Each layer constituting the electron injection layer (51) or other electron transport region (5) is not particularly limited but may include, for example, known electron injection materials. Examples of electron injection materials include lanthanide metals such as LiF, LiQ (Lithium quinolate), Li2O, BaO, NaCl, CsF, and Yb, or halogenated metals such as RbCl. The electron injection layer (51) is not particularly limited but may include, for example, an insulating organometallic salt and an electron transport material described later. The organometallic salt is not particularly limited but may be, for example, a material with an energy band gap of 4 eV or more. Examples of organometallic salts include metal acetate salts, metal benzoate salts, metal acetate salts, metal acetylacetonate salts, or metal stearate salts.

[0703] Each layer constituting the electron transport layer (52) or other electron transport region (5) is not particularly limited, but may include, for example, known electron transport materials. Electron transport materials include, for example, anthracene compounds, Alq3 (tris(8-hydroxyquinolinate)aluminum), 1,3,5-tri[(3-pyridyl)-phen-3-yl]benzene, 2,4,6-tris(3'-pyridine-3-yl)biphenyl-3-yl)-1,3,5-triazine, 2-(4-(N-phenylbenzimidazole-1-ylphenyl)-9,10-dinaphthylanthracene, TPBi (1,3,5-tri(1-phenyl-1H-benzo[d]imidazole-2-yl)phenyl), BCP (2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline), Bphen (4,7-diphenyl-1,10-phenanthroline), Examples include TAZ (3-(4-biphenyl)-4-phenyl-5-tert-butylphenyl-1,2,4-triazole), NTAZ (4-(naphthalene-1-yl)-3,5-diphenyl-4H-1,2,4-triazole), tBu-PBD (2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole), BAlq (bis(2-methyl-8-quinolinorato-N1,O8)-(1,1'-biphenyl-4-orato)aluminum), Bebq2 (beryllium bis(benzoquinoline-10-oleate), ADN (9,10-di(naphthalene-2-yl)anthracene), LiQ (lithium quinolate), and the following compound ET1. Additionally, TRE314 (manufactured by Tore Corporation, electronic transport material) may be used.

[0704]

[0705] The hole blocking layer (53) is a layer that prevents the injection of holes from the hole transport region (3) into the electron transport region (5). The material included in the hole blocking layer (53) is not particularly limited, and a known material used in the hole blocking layer (53) can be used. The hole blocking layer (53) may include, for example, a known hole blocking material. Examples of hole blocking materials include BCP (2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline), BPhen (4,7-diphenyl-1,10-phenanthroline), etc. Additionally, for example, a host material included in the above-mentioned light-emitting layer (material for organic electroluminescent devices) can be used, and the above-mentioned compound H77, which is a host material, can be given as an example.

[0706] The thickness of the electron transport region (5) is not specifically limited, but may be 0.1 nm or more and 200 nm or less, or 30 nm or more and 150 nm or less. Additionally, for each layer constituting the electron transport region (5), the thickness of the electron transport layer (52) is not specifically limited, but may be 10 nm or more and 100 nm or less, or 15 nm or more and 50 nm or less. The thickness of the hole blocking layer (53) is not specifically limited, but may be 1 nm or more and 100 nm or less, or 5 nm or more and 30 nm or less. The thickness of the electron injection layer (51) is not specifically limited, but may be, for example, 0.1 nm or more and 10 nm or less, or 0.3 nm or more and 9 nm or less. When the thickness of the electron injection layer (51) is within the above range, better electron injection characteristics can be obtained while suppressing a substantial increase in driving voltage. In addition, when the thickness of the electron transport region (5), electron injection layer (51), electron transport layer (52), or hole blocking layer (53) is within the above range, better electron transport characteristics can be obtained while suppressing the rise in the actual driving voltage.

[0707] The method of forming the electron transport region (5) or each layer constituting it is not particularly limited, but known methods of forming films such as vacuum deposition, spin coating, LB method, inkjet printing, laser printing, and laser thermal transfer can be cited.

[0708] The second electrode (6) is placed over the electron transport region (5). The second electrode (6) is conductive. In an organic electroluminescent device according to one embodiment of the present invention, the second electrode (6) may be a common electrode or a cathode. The second electrode (6) may be a transmissive electrode, a transmissive electrode, or a reflective electrode.

[0709] The material constituting the second electrode (6) is not particularly limited, but may include, for example, a metal alloy or a conductive compound. If the second electrode (6) is a transmissive electrode, the second electrode (6) may include a transparent metal oxide, for example, ITO, IZO, ZnO, ITZO, etc. If the second electrode (6) is a semi-transmissive electrode or a reflective electrode, the second electrode (6) may include Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF / Ca, LiF / Al, Mo, Ti, or a compound or mixture containing these (for example, a mixture of Ag and Mg).

[0710] The second electrode (6) may be a single layer made of a single material, or a single layer made of multiple different materials. Additionally, the second electrode (6) may be a multilayer structure having multiple layers made of multiple different materials.

[0711] The thickness of the second electrode (6) is not particularly limited, but can be 10 nm or more and 1000 nm or less.

[0712] The second electrode (6) may be connected to an auxiliary electrode (not shown). By connecting the second electrode (6) to the auxiliary electrode, the resistance of the second electrode (6) can be further reduced.

[0713] In addition, a capping layer (not shown) may be further disposed on the second electrode (6). The capping layer (not shown) is not particularly limited, but may be a layer including, for example, α-NPD, NPB, TPD, m-MTDATA, Alq3, CuPc, TPD15 (N4,N4,N4',N4'-tetra(biphenyl-4-yl), biphenyl 4,4'-diamine), TCTA (4,4',4"-tri-9-carbazoleyltriphenylamine), N,N'-bis(naphthalene-1-yl), etc.

[0714] In addition, the materials constituting each of the above layers and each electrode may be used as a single type or in combination of two or more types.

[0715] In the organic electroluminescent device (10) of FIGS. 1 to 3, the nitrogen-containing condensed ring compound, the fluorescent light-emitting agent, or the organic electroluminescent device material may be included in the light-emitting layer (4), but may also be included in an organic layer other than the light-emitting layer (4). Additionally, the nitrogen-containing condensed ring compound, the fluorescent light-emitting agent, or the organic electroluminescent device material may be included in the light-emitting layer (4) and an organic layer other than the light-emitting layer (4).

[0716] In the organic electroluminescent device (10) of FIGS. 1 to 3, when a voltage is applied to the first electrode (2) and the second electrode (6), respectively, holes injected from the first electrode (2) move to the light-emitting layer (4) via the hole transport region (3), and electrons injected from the second electrode (6) move to the light-emitting layer (4) via the electron transport region (5). The electrons and holes recombine in the light-emitting layer (4) to generate excitons, and light is emitted as the excitons fall from the excited state to the ground state.

[0717] Examples

[0718] The present invention will be explained in more detail using the following examples and comparative examples, but the technical scope of the present invention is not limited to the following examples.

[0719] <Simulation Evaluation of Condensed Ring Compounds>

[0720] In “High-Performance Dibenzoheteraborin-Based Thermally Activated Delayed Fluorescence Emitters: Molecular Architectonics for Concurrently Achieving Narrowband Emission and Efficient Triplet-Singlet Spin Conversion” in Seob Park, Kyohei Matsuo, Naoya Aizawa, and Takuma Yasuda, Advanced Functional Materials 2018, 28, 1802031, the spectral width of fluorescence emission (Full Width at Half Maximum, FWHM) is a reorganization energy expressed as the difference between the energy of the ground state (S0) in the stable structure of the first excited singlet state (S1) [E(S0@S1)] and the energy of the ground state (S0) in the stable structure of the ground state (S0) [E(S0@S0)]. Something closely related to [E(S0@S1)-E(S0@S0)] is appearing.

[0721] [Verification of the relationship between rearrangement energy and the spectral width of fluorescence emission]

[0722] First, the relationship between the rearrangement energy [E(S0@S1)-E(S0@S0)] and the spectral width (FWHM) of the fluorescence emission was established as follows.

[0723] (Calculation by Density Functional Theory (DFT))

[0724] For the condensed ring compounds R1 to R3 disclosed below, the following calculations were performed using Density Functional Theory (DFT).

[0725]

[0726] The energy of the ground state (S0) in the stable structure of the first singlet state (S1) [E(S0@S1)] and the energy of the ground state (S0) in the stable structure of the ground state (S0) [E(S0@S0)] were calculated, and from this difference, the rearrangement energy [E(S0@S1)] - [E(S0@S0)] (eV) was calculated.

[0727] In addition, the energy [E(S1@S1)] of the first excited singlet state (S1) in the stable structure of the first excited singlet state (S1) was calculated, and the energy [E(S0@S0)] of the ground state (S0) in the stable structure of the ground state (S0) was calculated from the difference between this value and the energy [E(S1@S1)] of the ground state (S0) in the stable structure of the ground state (S0) to calculate the energy of the adiabatic first excited singlet state (S1) [E(S1@S1)] - [E(S0@S0)] (eV).

[0728] Then, the fluorescence wavelength (nm) was calculated by converting the energy (eV) of the adiabatic first excited singlet state (S1) into optical wavelengths (nm).

[0729] In addition, the oscillator strength f in the stable structure of the first excited singlet state (S1) was calculated.

[0730] In addition, the HOMO (Highest Occupied Molecular Orbital) energy and LUMO (Lowest Unoccupied Molecular Orbital) energy were calculated.

[0731] Here, the calculations by Density Functional Theory (DFT) were performed using Gaussian 16 (Gaussian Inc.) as the calculation software with the following (I), (II), and (III) calculation methods:

[0732] (I) S0 calculation method: Structural optimization calculation by DFT including functional B3LYP, basis function 6-31 G(d, p), and toluene solvent effect (PCM);

[0733] (II) S1 calculation method: Structural optimization calculation by time-dependent DFT (TDDFT) including functional B3LYP, basis function 6-31 G(d, p), and toluene solvent effect (PCM);

[0734] (III) S0 calculation method: Calculation of input structures by DFT including functional B3LYP, basis function 6-31 G(d, p), and toluene solvent effect (PCM).

[0735] More specifically, the calculation of each item was performed using the following calculation method:

[0736] · Energy of the ground state (S0) in the stable structure of the ground state (S0) [E(S0@S0)]: the calculation method of (I) above;

[0737] · Energy [E(S1@S1)] of the first excited singlet state (S1) in the stable structure of the first excited singlet state (S1): the calculation method of (II) above;

[0738] · Ground state (S0) energy [E(S0@S1)] in the stable structure of the first excited singlet state (S1): the calculation method of (II) and (III) above;

[0739] · Redistribution energy [E(S0@S1)]-[E(S0@S0)]: Calculation method of (I), (II) and (III) above;

[0740] · Adiabatic first excited singlet state (S1) energy [E(S1@S1)]-[E(S0@S0)]: Calculation method of (I) and (II) above;

[0741] · Fluorescence wavelength (nm): Calculation method of (I) and (II) above;

[0742] · Oscillator strength f in the stable structure of the first excited singlet state (S1): calculation method of (II) above;

[0743] · HOMO and LUMO: Calculation method of (I) above.

[0744] In addition, Figure 4 is an explanatory diagram that qualitatively explains the relationship between each energy.

[0745] (Measurement of the full width of spectral

[0746] 1×10 of condensed ring compounds R1 to R3 -5 M(=mol / dm 3 For each toluene solution of , mol / L), measurements were taken at room temperature with an excitation wavelength of 320 nm using a spectrofluorescence photometer F7000 manufactured by Hitachi High-Tech Science Corp., and the peak wavelength (nm) of the fluorescence emission and the spectral width of the fluorescence emission (FWHM of the peak of the fluorescence emission spectrum) were evaluated.

[0747] These results are shown in Table 2 below.

[0748] (Table 2) Calculation results by density functional method and FWHM measurement results of fluorescence emission

[0749] compound Calculation by density function method Actual measurements HOMO(eV) LUMO(eV) Adiabatic first excited single state (S1) energy (eV) vibrator strength f redistribution energy (eV) Fluorescence wavelength (nm) PL peak wavelength (nm) PLFWHM(nm) R1 -4.88 -1.23 2.99 0.214 0.109 415 453 22 R2 -5.94 -2.36 2.96 0.161 0.132 419 451 26 R3 -5.02 -1.96 2.62 0.491 0.164 474 445 42

[0750] From the results in Table 2 above, it was confirmed that the color of the fluorescence wavelength (nm) calculated by the density functional method and the measured peak wavelength show values ​​that are somewhat close. From this, it was confirmed that the hue estimated by the calculation according to the density functional method and the measured hue are of the same color family. Here, a graph of the FWHM of fluorescence emission in the measured PL versus the rearrangement energy (eV) calculated according to the density functional method for condensed ring compounds R1 to R3 is shown in Figure 5. From the results in Figure 5, it was confirmed that there is a correlation between the rearrangement energy (eV) calculated by the density functional method and the FWHM of fluorescence emission, and that as the rearrangement energy (eV) decreases, the FWHM of fluorescence emission decreases, that is, the spectral width of fluorescence emission narrows.

[0751] [Evaluation of Compound by Calculation 1: Calculation of E(S1) in the Ground State of the Compound of the Present Invention]

[0752] The singlet energy E(S1) (energy of the first adiabatic excited singlet state (S1)) of the nitrogen-containing condensed ring compounds of the present invention was calculated. Specifically, for some of the nitrogen-containing condensed ring compounds 1 to 317 exemplified in the description of the nitrogen-containing condensed ring compounds according to the present invention shown in Tables 3 to 9 below, the singlet energy E(S1) was calculated by the density functional method. Additionally, the compound numbers shown in Tables 3 to 9 below represent the numbers of the compounds specifically exemplified above.

[0753] ≪Calculation Method≫

[0754] E(S1): Calculated by the time-dependent DFT (TDDFT) with the functional B3LYP and basis function 6-31 G(d, p) in the ground state optimization structure obtained by the DFT using the functional B3LYP and basis function 6-31 G(d, p).

[0755] Calculation software used: Gaussian 16 (Gaussian Inc.).

[0756] [Evaluation of Compound by Calculation 2: Calculation of Oscillator Intensity (f), Relocation Energy, and Fluorescence Wavelength of Compound of the Present Invention]

[0757] By the same method as described in the above [Confirmation of the relationship between rearrangement energy and spectral width of fluorescence emission], the oscillator intensity f, rearrangement energy, and fluorescence wavelength were calculated for some of the nitrogen-containing condensed ring compounds 1 to 317 exemplified as nitrogen-containing condensed ring compounds according to the present invention.

[0758] The results of the above calculations are shown in Tables 3 to 9 below.

[0759] (Table 3) Calculation results by density functional method

[0760] compound Calculation by density functional HOMO(eV) LUMO(eV) Adiabatic first excited single state (S1) energy (eV) Fluorescence wavelength (nm) vibrator strength f redistribution energy (eV) 1 -5.19 -1.90 2.76 450 0.403 0.076 Examples 2 -5.16 -1.88 2.75 451 0.460 0.080 Examples 3 -5.18 -1.85 2.80 443 0.347 0.062 Examples 5 -5.28 -1.94 2.80 442 0.200 0.058 Examples 6 -5.24 -1.91 2.78 446 0.179 0.068 Examples 7 -5.30 -1.92 2.86 434 0.303 0.055 Examples 8 -5.23 -1.90 2.79 445 0.189 0.065 Examples 9 -5.31 -2.00 2.77 447 0.692 0.096 Examples 10 -5.26 -1.97 2.76 449 0.982 0.105 Examples 11 -5.31 -1.90 2.88 430 0.318 0.060 Examples 12 -5.26 -1.95 2.78 446 0.823 0.099 Examples 13 -5.19 -1.88 2.78 447 0.578 0.093 Examples 14 -5.18 -1.90 2.76 450 0.608 0.082 Examples 15 -5.26 -1.87 2.87 432 0.254 0.062 Examples 16 -5.23 -1.84 2.86 433 0.242 0.063 Examples 17 -5.23 -1.84 2.87 432 0.262 0.060 Examples 18 -5.22 -1.83 2.86 433 0.239 0.064 Examples 19 -5.32 -2.09 2.70 459 0.556 0.101 Examples 24 -5.30 -2.10 2.68 463 1.053 0.105 Examples 28 -5.45 -2.10 2.83 439 0.389 0.048 Examples 29 -5.33 -2.06 2.73 454 0.866 0.107 Examples 30 -5.32 -1.99 2.80 443 0.186 0.079 Examples 32 -5.36 -2.04 2.79 444 0.339 0.058 Examples 34 -5.42 -2.09 2.81 442 0.310 0.051 Examples 35 -5.73 -2.31 2.88 431 0.249 0.081 Examples 37 -5.78 -2.37 2.89 429 0.301 0.064 Examples 39 -5.61 -2.13 2.95 420 0.317 0.075 Examples 40 -5.60 -2.28 2.80 444 0.282 0.069 Examples 41 -5.61 -2.19 2.90 428 0.306 0.068 Examples 42 -5.48 -2.22 2.73 455 0.246 0.072 Examples 43 -5.39 -2.05 2.83 438 0.262 0.051 Examples 44 -5.44 -1.95 2.96 418 0.306 0.071 Examples 45 -5.39 -2.07 2.79 444 0.189 0.049 Examples 46 -5.38 -1.99 2.88 430 0.306 0.057 Examples 47 -6.07 -2.63 2.91 425 0.343 0.067 Examples 48 -5.68 -2.27 2.89 428 0.326 0.065 Examples 49 -5.55 -2.18 2.85 434 0.260 0.057 Examples 53 -5.37 -2.16 2.69 461 0.535 0.108 Examples

[0761] (Table 4) Calculation results by density functional method

[0762] compound Calculation by density functional HOMO(eV) LUMO(eV) Adiabatic first excited single state (S1) energy (eV) Fluorescence wavelength (nm) vibrator strength f redistribution energy (eV) 56 -6.22 -2.98 2.73 454 0.358 0.068 Examples 57 -6.23 -2.81 2.90 427 0.335 0.056 Examples 58 -5.91 -2.55 2.84 437 0.318 0.069 Examples 59 -5.94 -2.49 2.92 424 0.338 0.075 Examples 60 -5.38 -2.26 2.60 477 0.302 0.101 Examples 61 -5.40 -2.01 2.87 432 0.394 0.058 Examples 63 -5.48 -2.09 2.87 432 0.548 0.057 Examples 64 -5.18 -1.92 2.73 455 0.184 0.058 Examples 65 -5.28 -2.04 2.72 455 0.499 0.069 Examples 66 -5.26 -1.99 2.72 456 0.190 0.067 Examples 69 -5.32 -1.91 2.88 430 0.347 0.065 Examples 70 -5.31 -1.92 2.86 434 0.363 0.060 Examples 71 -5.30 -1.94 2.83 438 0.337 0.050 Examples 73 -5.09 -1.87 2.69 460 0.162 0.060 Examples 74 -5.25 -2.03 2.69 461 0.620 0.106 Examples 75 -5.20 -1.98 2.70 458 0.581 0.069 Examples 76 -5.18 -1.94 2.68 463 0.144 0.111 Examples 79 -5.25 -1.99 2.72 456 0.574 0.098 Examples 80 -5.19 -1.95 2.72 456 0.526 0.066 Examples 81 -5.17 -1.91 2.71 458 0.137 0.114 Examples 83 -5.37 -1.97 2.87 432 0.362 0.072 Examples 84 -5.35 -1.98 2.84 436 0.355 0.059 Examples 85 -5.34 -2.00 2.81 442 0.319 0.050 Examples 86 -5.30 -2.04 2.74 452 0.711 0.079 Examples 87 -5.33 -2.09 2.70 459 0.573 0.109 Examples 89 -5.28 -2.13 2.65 469 0.984 0.103 Examples 90 -5.30 -2.07 2.70 460 0.412 0.074 Examples 91 -5.27 -2.00 2.71 458 0.154 0.109 Examples 92 -5.28 -2.10 2.67 464 0.992 0.097 Examples 98 -5.34 -2.09 2.73 453 0.593 0.075 Examples 99 -5.30 -2.06 2.73 455 0.868 0.088 Examples 100 -5.30 -2.04 2.74 452 0.738 0.081 Examples 101 -5.34 -2.10 2.71 457 0.502 0.075 Examples 102 -5.30 -2.07 2.69 461 0.387 0.075 Examples 103 -5.30 -2.07 2.70 459 0.432 0.073 Examples 104 -5.39 -2.10 2.74 453 0.138 0.113 Examples 105 -5.25 -1.97 2.73 455 0.157 0.100 Examples 106 -5.45 -2.20 2.71 458 0.674 0.108 Examples

[0763] (Table 5) Calculation results by density functional method

[0764] compound Calculation by density functional HOMO(eV) LUMO(eV) Adiabatic first excited single state (S1) energy (eV) Fluorescence wavelength (nm) Vibrator strength f redistribution energy (eV) 107 -5.30 -2.12 2.65 468 0.677 0.106 Examples 108 -5.40 -2.15 2.72 456 0.563 0.084 Examples 109 -5.27 -2.03 2.72 455 1.067 0.103 Examples 110 -5.27 -2.05 2.71 458 1.046 0.101 Examples 111 -5.27 -1.98 2.76 450 1.038 0.107 Examples 112 -5.21 -1.91 2.76 449 0.781 0.101 Examples 113 -5.21 -1.93 2.75 451 0.885 0.095 Examples 114 -5.25 -1.92 2.80 443 0.530 0.093 Examples 115 -5.23 -1.88 2.82 440 0.235 0.052 Examples 122 -5.26 -2.01 2.71 457 0.486 0.099 Examples 123 -5.23 -1.98 2.73 454 0.509 0.071 Examples 124 -5.23 -1.86 2.87 431 0.308 0.086 Examples 125 -5.20 -1.84 2.83 437 0.302 0.052 Examples 126 -5.21 -1.94 2.73 454 0.410 0.095 Examples 127 -5.18 -1.90 2.75 451 0.405 0.070 Examples 128 -5.15 -1.85 2.76 450 0.239 0.053 Examples 129 -5.23 -1.96 2.74 452 0.393 0.067 Examples 130 -5.20 -1.92 2.73 453 0.209 0.061 Examples 133 -5.17 -1.85 2.78 446 0.416 0.089 Examples 134 -5.14 -1.81 2.81 441 0.298 0.054 Examples 135 -5.17 -1.87 2.77 448 0.420 0.079 Examples 136 -5.14 -1.83 2.78 446 0.237 0.051 Examples 137 -5.27 -2.01 2.75 452 0.613 0.080 Examples 138 -5.28 -1.99 2.76 450 0.466 0.087 Examples 139 -5.25 -2.03 2.69 460 0.285 0.080 Examples 140 -5.23 -1.86 2.84 436 0.286 0.057 Examples 141 -5.23 -1.85 2.86 434 0.330 0.056 Examples 142 -5.23 -1.93 2.77 448 0.405 0.085 Examples 143 -5.28 -1.91 2.84 437 0.265 0.052 Examples 144 -5.22 -1.95 2.73 454 0.360 0.088 Examples 145 -5.26 -1.90 2.83 439 0.250 0.052 Examples 146 -5.23 -1.87 2.83 439 0.261 0.051 Examples 147 -5.31 -1.98 2.80 443 0.639 0.092 Examples 148 -5.24 -1.91 2.79 444 0.505 0.089 Examples 149 -5.19 -1.93 2.74 453 0.603 0.074 Examples 150 -5.21 -1.96 2.72 456 0.522 0.100 Examples 151 -5.18 -1.92 2.73 454 0.346 0.067 Examples 152 -5.16 -1.88 2.73 455 0.172 0.085 Examples

[0765] (Table 6) Calculation results by density functional

[0766] compound Calculation by density functional HOMO(eV) LUMO(eV) Adiabatic first excited single state (S1) energy (eV) Fluorescence wavelength (nm) vibrator strength f redistribution energy (eV) 153 -5.47 -2.05 2.82 440 0.238 0.089 Examples 154 -5.27 -1.95 2.78 446 0.621 0.094 Examples 155 -5.24 -1.90 2.80 443 0.192 0.072 Examples 156 -5.25 -1.94 2.78 446 0.655 0.096 Examples 157 -5.21 -1.88 2.80 443 0.198 0.057 Examples 159 -5.21 -1.84 2.83 438 0.296 0.053 Examples 160 -5.24 -1.91 2.79 444 0.493 0.092 Examples 161 -5.21 -1.90 2.77 447 0.656 0.098 Examples 162 -5.21 -1.92 2.76 449 0.794 0.089 Examples 165 -5.21 -1.84 2.85 435 0.345 0.069 Examples 166 -5.21 -1.80 2.88 430 0.370 0.069 Examples 167 -5.20 -1.84 2.83 438 0.284 0.053 Examples 168 -5.19 -1.83 2.82 439 0.245 0.048 Examples 169 -5.17 -1.81 2.84 437 0.328 0.057 Examples 172 -5.21 -1.90 2.77 447 0.656 0.098 Examples 173 -5.21 -1.92 2.76 449 0.794 0.089 Examples 174 -5.28 -1.88 2.87 432 0.344 0.069 Examples 175 -5.19 -1.81 2.86 434 0.339 0.071 Examples 176 -5.19 -1.81 2.86 434 0.293 0.052 Examples 177 -5.29 -1.90 2.87 433 0.319 0.060 Examples 178 -5.17 -1.84 2.81 442 0.336 0.073 Examples 179 -5.22 -1.84 2.84 436 0.289 0.050 Examples 180 -5.24 -1.94 2.77 448 0.745 0.101 Examples 181 -5.23 -1.94 2.76 449 0.717 0.088 Examples 182 -5.22 -1.92 2.76 449 0.632 0.096 Examples 183 -5.20 -1.92 2.75 450 0.680 0.082 Examples 184 -5.27 -1.89 2.85 435 0.385 0.070 Examples 185 -5.21 -1.81 2.86 433 0.371 0.071 Examples 186 -5.20 -1.84 2.84 437 0.361 0.059 Examples 187 -5.22 -1.95 2.74 453 0.539 0.092 Examples 188 -5.24 -1.93 2.78 446 0.617 0.093 Examples 189 -5.23 -1.94 2.77 448 0.886 0.097 Examples 190 -5.23 -1.94 2.77 448 0.886 0.097 Examples 191 -5.25 -1.87 2.85 434 0.371 0.068 Examples 192 -5.20 -1.80 2.87 431 0.362 0.069 Examples 193 -5.18 -1.82 2.84 437 0.351 0.059 Examples 194 -5.33 -1.95 2.77 447 0.063 0.171 Examples 195 -5.23 -1.92 2.78 446 0.673 0.093 Examples

[0767] (Table 7) Calculation results by density functional method

[0768] compound Calculation by density functional HOMO(eV) LUMO(eV) Adiabatic first excited single state (S1) energy (eV) Fluorescence wavelength (nm) vibrator strength f redistribution energy (eV) 223 -5.27 -1.90 2.80 443 0.085 0.145 Examples 224 -5.29 -1.93 2.84 437 0.422 0.079 Examples 226 -5.18 -1.83 2.82 440 0.155 0.100 Examples 227 -5.23 -1.85 2.84 436 0.418 0.081 Examples 229 -5.20 -1.85 2.79 444 0.100 0.121 Examples 230 -5.21 -1.87 2.81 441 0.374 0.066 Examples 232 -5.28 -1.91 2.84 436 0.351 0.074 Examples 233 -5.27 -1.89 2.84 437 0.157 0.080 Examples 234 -5.20 -1.83 2.84 437 0.345 0.077 Examples 235 -5.18 -1.82 2.84 437 0.289 0.058 Examples 236 -5.20 -1.86 2.81 441 0.321 0.064 Examples 237 -5.19 -1.84 2.82 440 0.134 0.089 Examples 238 -5.32 -1.95 2.85 435 0.301 0.054 Examples 239 -5.33 -1.93 2.88 430 0.337 0.066 Examples 240 -5.28 -1.91 2.84 436 0.308 0.055 Examples 241 -5.31 -1.91 2.87 432 0.333 0.064 Examples 242 -5.18 -1.85 2.80 443 0.286 0.054 Examples 243 -5.19 -1.84 2.83 438 0.354 0.062 Examples 244 -5.20 -1.83 2.84 436 0.305 0.058 Examples 245 -5.21 -1.82 2.87 433 0.342 0.072 Examples 246 -5.19 -1.88 2.77 447 0.481 0.088 Examples 247 -5.19 -1.88 2.78 446 0.482 0.088 Examples 249 -5.22 -1.84 2.85 435 0.235 0.060 Examples 250 -5.17 -1.88 2.77 448 0.615 0.081 Examples 251 -5.26 -1.97 2.76 450 0.711 0.096 Examples 252 -5.24 -1.96 2.75 451 0.530 0.088 Examples 253 -5.23 -1.94 2.76 450 0.578 0.091 Examples 255 -5.21 -1.94 2.74 453 1.155 0.116 Examples 256 -5.20 -1.93 2.74 453 0.823 0.101 Examples 257 -5.19 -1.91 2.75 452 0.955 0.108 Examples 258 -5.34 -2.09 2.70 459 1.468 0.146 Examples 259 -5.15 -1.78 2.84 437 0.229 0.056 Examples 260 -5.16 -1.76 2.87 432 0.256 0.066 Examples 261 -5.35 -2.01 2.80 442 0.248 0.058 Examples 262 -5.39 -2.02 2.83 437 0.272 0.061 Examples 263 -5.21 -1.87 2.81 442 0.223 0.058 Examples 264 -5.27 -1.94 2.79 444 0.223 0.058 Examples 266 -5.25 -1.89 2.83 438 0.267 0.059 Examples

[0769] (Table 8) Calculation results by density functional method

[0770] compound Calculation by density functional HOMO(eV) LUMO(eV) Adiabatic first excited single state (S1) energy (eV) Fluorescence wavelength (nm) vibrator strength f redistribution energy (eV) 267 -5.32 -1.99 2.80 443 0.235 0.058 Examples 268 -5.35 -2.01 2.80 442 0.248 0.058 Examples 269 -5.43 -2.14 2.76 450 1.044 0.118 Examples 270 -5.36 -2.12 2.71 458 0.426 0.092 Examples 271 -5.40 -2.17 2.70 459 0.346 0.089 Examples 272 -5.25 -1.96 2.75 451 0.433 0.088 Examples 273 -5.29 -2.02 2.74 452 0.456 0.089 Examples 274 -5.27 -1.98 2.76 450 0.565 0.091 Examples 275 -5.27 -1.96 2.76 450 0.343 0.094 Examples 277 -5.36 -2.12 2.71 458 0.425 0.092 Examples 282 -5.27 -1.94 2.80 444 0.266 0.082 Examples 283 -5.38 -2.11 2.68 462 0.282 0.094 Examples 284 -5.27 -1.95 2.77 448 0.292 0.094 Examples 285 -5.33 -2.06 2.73 454 0.316 0.090 Examples 286 -5.30 -2.00 2.76 450 0.376 0.090 Examples 287 -5.32 -2.00 2.76 448 0.300 0.106 Examples 288 -5.13 -1.82 2.76 449 0.211 0.070 Examples 289 -5.09 -1.83 2.70 459 0.243 0.070 Examples 293 -5.00 -1.69 2.80 443 0.381 0.071 Examples 295 -5.35 -1.89 2.93 423 0.257 0.072 Examples 297 -5.28 -1.92 2.84 436 0.258 0.062 Examples 298 -5.43 -2.12 2.76 449 0.211 0.083 Examples 299 -5.50 -2.21 2.75 450 0.238 0.082 Examples 300 -5.51 -2.12 2.86 434 0.258 0.076 Examples 301 -5.36 -2.15 2.66 466 0.219 0.088 Examples 303 -5.20 -1.79 2.88 430 0.302 0.073 Examples 305 -5.09 -1.77 2.79 445 0.290 0.065 Examples 306 -5.28 -1.89 2.87 432 0.237 0.061 Examples 307 -5.33 -2.03 2.77 448 0.796 0.099 Examples 308 -5.26 -1.87 2.87 432 0.265 0.059 Examples 309 -5.25 -1.86 2.80 443 0.261 0.015 Examples 310 -5.26 -1.88 2.86 434 0.242 0.059 Examples 311 -5.31 -1.96 2.82 440 0.525 0.086 Examples 312 -5.33 -1.93 2.87 432 0.328 0.063 Examples 313 -5.33 -1.95 2.85 435 0.345 0.073 Examples 314 -5.27 -1.95 2.78 446 0.624 0.095 Examples

[0771] (Table 9) Calculation results by density functional method

[0772] compound Calculation by density functional HOMO(eV) LUMO(eV) Adiabatic first excited single state (S1) energy (eV) Fluorescence wavelength (nm) vibrator strength f redistribution energy (eV) 315 -5.30 -1.99 2.78 446 0.173 0.056 Examples 316 -5.33 -1.86 2.94 422 0.278 0.077 Examples 317 -5.27 -1.92 2.83 437 0.264 0.063 Examples

[0773] As shown in Tables 3 to 9 above, the nitrogen-containing condensed ring compounds of the present invention have a small rearrangement energy. From this, referring to FIG. 5, it is presumed that the FWHM of the nitrogen-containing condensed ring compounds of the present invention is reduced and the color purity is increased. Furthermore, it was confirmed that the nitrogen-containing condensed ring compounds of the present invention have a sufficiently large oscillator intensity f and exhibit excellent fluorescence emission efficiency.

[0774] From the above results, it was found that the nitrogen-containing condensed ring compound of the present invention has a small rearrangement energy, a large oscillator intensity f, and a very suitable blue fluorescence wavelength. From this, it was confirmed that the nitrogen-containing condensed ring compound of the present invention has a narrow emission spectrum width and can realize high color purity, so it is expected to be a blue light-emitting material that can improve the luminescence efficiency of organic EL devices.

[0775] [Evaluation of Compounds by Calculation 3]

[0776] For some of the nitrogen-containing condensed ring compounds 1 to 317 exemplified in the description of the nitrogen-containing condensed ring compounds according to the present invention above, and for the comparative compound C1 below, it was confirmed whether conditions (i) to (iv) below are satisfied. Additionally, these calculations were obtained using the Q-Chem program. The details of the calculation method are as described in the description of the nitrogen-containing condensed ring compounds according to the present invention.

[0777] <Condition (i)>

[0778] ΔE ST > ΔE ST2 + ΔE' TT

[0779] <Condition (ii)>

[0780] 0 eV < ΔE ST2 + ΔE' TT ≤ 1.0 eV

[0781] <Condition (iii)>

[0782] 0 eV < ΔE'TT ≤ 0.15 eV

[0783] <Condition (iv)>

[0784] ΔE ST2 > 0 eV

[0785] Under the above conditions (i) to (iv),

[0786] ΔE ST (eV) represents the value of the difference between the lowest singlet excitation energy (eV) calculated for the S1 equilibrium structure and the lowest triplet excitation energy (eV) calculated for the T1 equilibrium structure;

[0787] ΔE ST2 (eV) represents the value of the difference between the lowest singlet excitation energy (eV) calculated for the S1 equilibrium structure and the second lowest triplet excitation energy (eV) calculated for the T2 equilibrium structure;

[0788] ΔE' TT (eV) represents the value of the difference between the second lowest triplet excitation energy (eV) calculated for a T2 equilibrium structure and the lowest triplet excitation energy (eV) calculated for a T2 equilibrium structure.

[0789] Here, S1 equilibrium structure, T1 equilibrium structure, and T2 equilibrium structure refer to the structures that a molecule takes when it reaches each excited state, and represent the structure with the lowest energy for each state, that is, the most stable structure.

[0790] The results of these evaluations are shown in Table 10 below.

[0791] (Table 10) Evaluation results of conditions (i) to (iv) of nitrogen-containing condensed ring compounds

[0792] Compound No. ΔE ST [eV] ΔE ST2 [eV] ΔE' TT [eV] condition(i) Condition (ii) Condition (iii) Condition (iv) note 1 0.738 0.553 0.110 content content content content The present invention 2 0.739 0.542 0.111 content content content content The present invention 3 0.747 0.559 0.086 content content content content The present invention 5 0.647 0.463 0.133 content content content content The present invention 6 0.641 0.432 0.130 content content content content The present invention 7 0.717 0.528 0.146 content content content content The present invention 8 0.643 0.461 0.133 content content content content The present invention 9 0.821 0.591 0.118 content content content content The present invention 10 0.829 0.595 0.096 content content content content The present invention 12 0.827 0.593 0.107 content content content content The present invention 14 0.772 0.547 0.133 content content content content The present invention 19 0.762 0.579 0.133 content content content content The present invention 65 0.714 0.500 0.100 content content content content The present invention 66 0.571 0.402 0.109 content content content content The present invention 71 0.716 0.529 0.134 content content content content The present invention 75 0.702 0.484 0.091 content content content content The present invention 76 0.521 0.357 0.098 content content content content The present invention 79 0.772 0.547 0.199 content content content content The present invention 80 0.706 0.491 0.096 content content content content The present invention 81 0.548 0.377 0.109 content content content content The present invention 84 0.757 0.556 0.149 content content content content The present invention 85 0.697 0.510 0.129 content content content content The present invention 89 0.674 0.454 0.131 content content content content The present invention 114 0.794 0.576 0.113 content content content content The present invention 156 0.754 0.544 0.148 content content content content The present invention 160 0.625 0.436 0.141 content content content content The present invention 172 0.816 0.657 0.046 content content content content The present invention 194 0.708 0.471 0.069 content content content content The present invention 195 0.823 0.595 0.089 content content content content The present invention C1 0.775 0.582 0.157 content content dissatisfaction content Comparative example

[0793]

[0794]

[0795]

[0796]

[0797]

[0798] 18 (D8)

[0799]

[0800]

[0801]

[0802]

[0803]

[0804]

[0805]

[0806] <Synthesis of Nitrogen-Containing Condensed Ring Compounds>

[0807] Compounds D1, D2, D3, D4, D5, D6, D7, D8, and D9 were synthesized as follows for use in manufacturing an organic electroluminescent device. Here, compounds D1, D2, D3, D4, D5, D6, D7, D8, and D9 are each compounds identical to the nitrogen-containing condensed ring compounds 7, 6, 10, 12, 13, 14, 114, 18, and 195 mentioned above. In addition, Comparative Example compound C1 was prepared for use in manufacturing an organic electroluminescent device of the Comparative Example.

[0808] [Synthesis of Compound D1 (Compound 7 above)]

[0809]

[0810] Intermediate 1 Intermediate 2

[0811]

[0812] Intermediate 3 Compound D1

[0813] (Synthesis of Intermediate 1)

[0814] Tetrakistriphenylphosphine palladium (5.80 g, 5.0 mmol) was added to a mixture of 5-bromoindole (19.61 g, 100.0 mmol), 2,4,6-trimethylboric acid (21.40 g, 130.4 mmol), toluene (400 mL), ethanol (100 mL), and 1 M aqueous sodium carbonate solution (200 mL) under an inert gas atmosphere, and the mixture was heated and refluxed for 5 hours. After cooling at room temperature, the organic layer was extracted with toluene. The organic layer was dried with anhydrous magnesium sulfate and then filtered and concentrated. The resulting product was purified by silica gel column chromatography to obtain intermediate 1 as a colorless oil (16.54 g, 70.34 mmol, yield 70%).

[0815] (Synthesis of Intermediate 2)

[0816] A mixture of intermediate 1 (16.54 g, 70.34 mmol), 2-chlorobenzaldehyde (7.91 mL, 70.34 mmol), and 1,3-dimethylbarbituric acid (10.98 g, 70.32 mmol) was heated and stirred at 100°C for 30 minutes. The reaction mixture was washed with hexane and ethanol to obtain intermediate 2 as a white solid (32.62 g, 63.45 mmol, yield 90%).

[0817] (Synthesis of Intermediate 3)

[0818] Acetic acid (100 mL) was added to intermediate 2 (32.54 g, 63.31 mmol) and heated under reflux for 24 hours. The precipitated solid was recovered and washed with ethanol to obtain intermediate 3 as an off-white solid (11.81 g, 15.92 mmol, yield 50%).

[0819] (Synthesis of Compound D1)

[0820] Under an inert gas atmosphere, tetrabutylammonium hydroxide (37% methanol solution) (100 mL, 118 mmol) was added to a mixture of intermediate 3 (11.80 g, 15.92 mmol), copper(I) iodide (23.65 g, 124.2 mmol), and N,N-dimethylformamide (160 mL), and the mixture was heated and stirred at 120°C for 33 hours. The precipitated solid was recovered and washed with aqueous solutions of acetanitrile and ethylenediamine. The product was recrystallized into benzonitrile to obtain compound D1 as a yellow solid (8.99 g, 14.0 mmol, yield 88%).

[0821] The structure of the obtained compound D1 is a nuclear magnetic resonance device ( 1 Determined by H-NMR:

[0822] 1 H NMR (300 MHz, THF-d8), Δ2.09(s, 12H), 2.32(s, 6H), 6.91(s, 4H), 7.31-7.43(m, 4H), 7.56(dd, J=8.1 Hz, 2H), 8.11(d, J=8.1 Hz, 2H), 8.16(d, J=8.1 Hz, 2H), 8.25(s, 2H), 8.42(d, J=7.5 Hz, 2H).

[0823] [Synthesis of Compound D2 (Compound 6 above)]

[0824]

[0825] Intermediate 4 Intermediate 5

[0826]

[0827] Intermediate 6 Compound D2

[0828] (Synthesis of Intermediate 4)

[0829] Intermediate 4 was obtained by the same method as the synthesis of Intermediate 1, except that the corresponding reagent was changed (yield 73%).

[0830] (Synthesis of Intermediate 5)

[0831] Intermediate 5 was obtained by the same method as the synthesis of Intermediate 2, except that the corresponding reagent was changed (yield 33%).

[0832] (Synthesis of Intermediate 6)

[0833] Intermediate 6 was obtained by the same method as the synthesis of intermediate 3, except that the corresponding reagent was changed (yield 44%).

[0834] (Synthesis of Compound D2)

[0835] Compound D2 was obtained by the same method as the synthesis of compound D1, except that the corresponding reagent was changed (yield 67%).

[0836] The structure of the obtained compound D2 is a nuclear magnetic resonance device ( 1 Determined by H-NMR:

[0837] 1 H NMR (300 MHz, THF-d8), Δ1.39(s, 18H), 7.42-7.53(m, 6H), 7.61(br, 2H), 7.70(br, 4H), 7.81(br, 2H), 8.08-8.16(m, 4H), 8.55(br, 2H), 8.65(br, 2H).

[0838] [Synthesis of Compound D3 (Compound 10 above)]

[0839]

[0840] Intermediate 7 Intermediate 8

[0841]

[0842] Intermediate 9 Compound D3

[0843] (Synthesis of Intermediate 7)

[0844] Intermediate 7 was obtained by the same method as the synthesis of Intermediate 1, except that the corresponding reagent was changed (yield 35%).

[0845] (Synthesis of Intermediate 8)

[0846] Intermediate 8 was obtained by the same method as the synthesis of Intermediate 2, except that the corresponding reagent was changed (yield 89%).

[0847] (Synthesis of Intermediate 9)

[0848] Intermediate 9 was obtained by the same method as the synthesis of Intermediate 3, except for changing the corresponding reagent (yield 62%).

[0849] (Synthesis of Compound D3)

[0850] Compound D3 was obtained by the same method as the synthesis of compound D1, except that the corresponding reagent was changed (yield 64%).

[0851] The structure of the obtained compound D3 is a nuclear magnetic resonance device ( 1 Determined by H-NMR:

[0852] 1 H NMR (300 MHz, THF-d8), Δ1.39(s, 18H), 7.42-7.52(m, 6H), 7.60(br, 2H), 7.65-7.75(m, 6H), 8.16(br, 2H), 8.25(s, 2H), 8.54(br, 4H).

[0853] [Synthesis of Compound D4 (Compound 12 above)]

[0854]

[0855] Intermediate 10 Intermediate 11

[0856]

[0857] Intermediate 12 Compound D4

[0858] (Synthesis of Intermediate 10)

[0859] Intermediate 10 was obtained by the same method as the synthesis of Intermediate 1, except that the corresponding reagent was changed (yield 79%).

[0860] (Synthesis of Intermediate 11)

[0861] A mixture of intermediate 10 (18.01 g, 58.93 mmol), 2-chlorobenzaldehyde (6.62 mL, 58.93 mmol), and 1,3-dimethylbarbituric acid (9.20 g, 58.92 mmol) was heated and stirred at 100°C for 30 minutes. The product was purified by silica gel column chromatography to obtain intermediate 11 as a white solid (29.59 g, 50.65 mmol, yield 86%).

[0862] (Synthesis of Intermediate 12)

[0863] Intermediate 12 was obtained by the same method as the synthesis of intermediate 3, except that the corresponding reagent was changed (yield 40%).

[0864] (Synthesis of Compound D4)

[0865] Compound D4 was obtained by the same method as the synthesis of compound D1, except that the corresponding reagent was changed (yield 84%).

[0866] The structure of the obtained compound D4 is a nuclear magnetic resonance device ( 1 Determined by H-NMR:

[0867] 1 H NMR (300 MHz, THF-d8), Δ1.52(s, 36H), 7.51-7.61(m, 4H), 7.70(br, 2H), 7.75(br, 4H), 7.79(br, 2H), 8.25(br, 2H), 8.35(s, 2H), 8.60(br, 2H), 8.64(br, 2H).

[0868] [Synthesis of Compound D5 (Compound 13 above)]

[0869]

[0870] Intermediate 10 Intermediate 13 Intermediate 14

[0871]

[0872] Compound D5

[0873] (Synthesis of Intermediate 13)

[0874] Intermediate 13 was obtained by the same method as the synthesis of intermediate 11, except that the corresponding reagent was changed (yield 67%).

[0875] (Synthesis of Intermediate 14)

[0876] Intermediate 14 was obtained by the same method as the synthesis of intermediate 3, except that the corresponding reagent was changed (yield 67%).

[0877] (Synthesis of Compound D5)

[0878] Compound D5 was obtained by the same method as the synthesis of compound D1, except that the corresponding reagent was changed (yield 72%).

[0879] The structure of the obtained compound D5 is a nuclear magnetic resonance device ( 1 Determined by H-NMR:

[0880] 1 H NMR (300 MHz, THF-d8), Δ1.53(s, 36H), 1.57(s, 18H), 7.58(d, J=8.1Hz, 2H), 7.61(br, 2H), 7.78(s, 4H), 7.82(d, J=8.1Hz, 2H), 8.18(s, 2H), 8.25(s, 2H), 8.44(br, 2H), 8.65(d, J=8.1Hz, 2H).

[0881] [Synthesis of Compound D6 (Compound 14 above)]

[0882] Intermediate 10 Intermediate 15 Intermediate 16

[0883]

[0884] Compound D6

[0885] (Synthesis of Intermediate 15)

[0886] Intermediate 15 was obtained by the same method as the synthesis of intermediate 11, except that the corresponding reagent was changed (yield 98%).

[0887] (Synthesis of Intermediate 16) ​

[0888] Intermediate 16 was obtained by the same method as the synthesis of intermediate 3, except that the corresponding reagent was changed (yield 51%).

[0889] (Synthesis of Compound D6)

[0890] Compound D6 was obtained by the same method as the synthesis of compound D1, except that the corresponding reagent was changed (yield 61%).

[0891] The structure of the obtained compound D6 was obtained using a nuclear magnetic resonance device ( 1 Confirmed by H-NMR:

[0892] 1 H NMR (300 MHz, THF-d8) Δ1.51(s, 36 H), 1.67(s, 18 H), 7.57(br, 2 H), 7.74-7.78(m, 4 H), 7.80-7.88(m, 4 H), 8.21-8.28(m, 2 H), 8.41(br, 2 H), 8.63-8.71(m, 4 H).

[0893] [Synthesis of Compound D7 (Compound 114 above)]

[0894]

[0895] Intermediate 17 Intermediate 18

[0896]

[0897] Intermediate 19 Compound D7

[0898] (Synthesis of Intermediate 17)

[0899] Under an inert gas atmosphere, tetrakistriphenylphosphine palladium (2.32 g, 2.0 mmol) was added to a mixture of (m-terphenyl 2'-yl) trilate (15.13 g, 40.00 mmol), 6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolane-2-yl)-1H-indole (11.65 g, 47.93 mmol), 1,4-dioxane (200 mL), and 1 M aqueous sodium carbonate solution (80 mL), and heated under reflux for 8 hours. After cooling to room temperature, the organic layer was extracted with chloroform. The organic layer was dried with anhydrous magnesium sulfate, filtered, and concentrated. The resulting product was purified by silica gel column chromatography to obtain intermediate 17 as a white solid (9.46 g, 37.4 mmol, yield 69%).

[0900] (Synthesis of Intermediate 18)

[0901] Intermediate 18 was obtained by the same method as the synthesis of intermediate 11, except that the corresponding reagent was changed (yield 72%).

[0902] (Synthesis of Intermediate 19)

[0903] Intermediate 19 was obtained by the same method as the synthesis of intermediate 3, except that the corresponding reagent was changed (yield 57%).

[0904] (Synthesis of Compound D7)

[0905] Compound D7 was obtained by the same method as the synthesis of compound D1, except that the corresponding reagent was changed (yield 72%).

[0906] The structure of the obtained compound D7 was analyzed using a nuclear magnetic resonance device ( 1 Confirmed by H-NMR:

[0907] 1H NMR (300 MHz, THF-d8) Δ6.95-7.22(m, 18 H), 7.26(d, J=7.5 Hz, 4 H), 7.43-7.63(m, 10 H), 7.76(br, 2 H), 7.82-7.89(m, 2 H), 8.32(d, J=8.1 Hz, 2 H), 8.52-8.59(m, 2 H).

[0908] [Synthesis of Compound D8 (Compound 18 above)]

[0909]

[0910] Intermediate 20 Intermediate 21

[0911]

[0912] Intermediate 22 Compound D8

[0913] (Synthesis of Intermediate 20)

[0914] Intermediate 20 was obtained by the same method as the synthesis of Intermediate 1, except that the corresponding reagent was changed (yield 91%).

[0915] (Synthesis of Intermediate 21)

[0916] Intermediate 21 was obtained by the same method as the synthesis of intermediate 3, except that the corresponding reagent was changed (yield 14%).

[0917] (Synthesis of Intermediate 22)

[0918] Intermediate 22 was obtained by the same method as the synthesis of intermediate 11, except that the corresponding reagent was changed (yield 31%).

[0919] (Synthesis of Compound D8)

[0920] Compound D8 was obtained by the same method as the synthesis of compound D1, except that the corresponding reagent was changed (yield 31%).

[0921] The structure of the obtained compound D8 was analyzed using a nuclear magnetic resonance device ( 1 Confirmed by H-NMR:

[0922] 1 H NMR (300 MHz, THF-d8) Δ1.48(s, 36 H), 5.52(d, J=8.4 Hz, 2 H), 7.07(dd, J=7.5, 7.5 Hz, 2 H), 7.37(dd, J=7.5, 7.5 Hz, 2 H), 7.55-7.66(m, 8 H), 7.87(br, 2 H), 8.67(d, J=7.5 Hz, 2 H), 8.73-8.77(m, 2 H).

[0923] [Synthesis of Compound D9 (Compound 195 above)]

[0924]

[0925] Intermediate 23

[0926]

[0927] Intermediate 24 Compound 9

[0928] (Synthesis of Intermediate 23)

[0929] Intermediate 23 was obtained by the same method as the synthesis of intermediate 3, except that the corresponding reagent was changed (yield 80%).

[0930] (Synthesis of Intermediate 24)

[0931] Intermediate 24 was obtained by the same method as the synthesis of intermediate 11, except that the corresponding reagent was changed (yield 49%).

[0932] (Synthesis of Compound D9)

[0933] Compound D9 was obtained by the same method as the synthesis of compound D1, except that the corresponding reagent was changed (yield 20%).

[0934] The structure of the obtained compound D9 was analyzed using a nuclear magnetic resonance device ( 1 Confirmed by H-NMR:

[0935] 1H NMR (300 MHz, THF-d8) Δ1.49(s, 36 H), 6.34(d, J=1.5 Hz, 2 H), 7.22(d, J=1.5 Hz, 4 H), 7.34-7.43(m, 2 H), 7.51-7.63(m, 10 H), 7.67(dd, J=7.5, 7.5 Hz, 2 H), 7.77-7.84(m, 4 H), 8.75(d, J=8.1 Hz, 2 H), 8.79(dd, J=6.0, 1.5 Hz, 2 H).

[0936] [Emission peak wavelength and full width at half maximum (FWHM) of the emission spectrum in photoluminescence (PL)]

[0937] 1Y10 of compounds D1 to D14 obtained above and comparative compound C1 -5 M(=mol / dm 3 Toluene solutions (mol / L) were prepared. For these solutions, measurements were performed at room temperature with an excitation wavelength of 360 nm using a spectrofluorescence photometer F7000 manufactured by Hitachi High-Tech Corp., and the peak wavelength (nm) of the emission and the full width at half maximum (FWHM) of the peak of the emission spectrum were evaluated. The results of these evaluations are shown in Table 11 below.

[0938] (Table 11) Emission peak wavelength and full width at half maximum (FWHM) of emission spectra of nitrogen-containing condensed ring compounds

[0939] Compound No. Peak wavelength of luminescence due to PL [nm] Full Width at Half Hinter of the Peak of the Emission Spectrum by PL [nm] note D1 452 12 The present invention D2 456 12 The present invention D3 457 13 The present invention D4 455 13 The present invention D5 455 15 The present invention D6 459 14 The present invention D7 459 16 The present invention D8 448 11 The present invention D9 456 14 The present invention C1 446 13 Comparative example

[0940] As shown in Table 11 above, it was confirmed that Compound D1 according to the present invention exhibits a good blue emission color in PL and achieves high color purity emission. Furthermore, as shown in Table 11 above, it was confirmed that Compounds D2 to D9 other than Compound D1 according to the present invention also exhibit a good blue emission color in PL and achieve high color purity emission, just like Compound D1 according to the present invention. From this, it is presumed that Compounds D2 to D9 according to the present invention, just like Compound D1 according to the present invention, also achieve a good blue emission color in an organic EL device and achieve high efficiency and high color purity emission. Additionally, in Table 11 above, the emission peak wavelength in PL of Comparative Compound C1 shows a blue emission color, and the full width at half maximum (FWHM) of the peak in the emission spectrum of Comparative Compound C1 in PL is narrow, showing high color purity emission. From this, it is believed that the blue emission color and the luminescence with good high color purity are attributed to a specific nitrogen-containing condensed ring structure that serves as the matrix.

[0941] Here, the graph of the FWHM of fluorescence emission in the measured PL for compounds D1 to D8 and the rearrangement energy (eV) calculated according to the density functional method is shown in Fig. 6. From the results in Fig. 6, it was confirmed that there is a correlation between the rearrangement energy (eV) calculated by the density functional method and the FWHM of fluorescence emission, and that as the rearrangement energy (eV) decreases, the FWHM of fluorescence emission decreases, that is, the spectral width of fluorescence emission narrows. For the other compounds whose rearrangement energies (eV) are shown in Tables 3 to 9, it can be inferred that the spectral width of fluorescence emission narrows, just as with compounds D1 to D8.

[0942] In addition, a graph of the fluorescence wavelength in the measured PL for compounds D1 to D8 and the emission wavelength calculated according to the density functional method is shown in FIG. 7. From the results in FIG. 7, it was confirmed that there is a correlation between the emission wavelength calculated by the density functional method and the fluorescence wavelength in the measured PL. It can be inferred that blue emission color can also be realized for the other compounds shown in Tables 3 to 9, just as with compounds D1 to D8.

[0943] [Evaluation of Solubility in Mesitylene]

[0944] Compounds D1 to D9 obtained above and comparative compound C1 were each placed in a 10 mg test tube, mesitylene was added, and the mixture was heated at 160°C. Mesitylene was added until the compounds were completely dissolved to calculate the solubility. The results of this evaluation are shown in Table 12 below.

[0945] (Table 12) Solubility of nitrogen-containing condensed ring compounds in mesitylene

[0946] Compound No. Solubility in mesitylene [g / L] note D1 2.0 The present invention D2 1.3 The present invention D3 1.0 The present invention D4 3.2 The present invention D5 10.1 The present invention D6 1.0 The present invention D7 3.1 The present invention D8 10.3 The present invention D9 3.0 The present invention C1 0.75 Comparative example

[0947] As shown in Table 12 above, it was confirmed that another compound D1 according to the present invention exhibits high solubility for mesitylene. Furthermore, as shown in Table 12 above, it was confirmed that other compounds D2 to D9 according to the present invention also exhibit high solubility for mesitylene, similar to compound D1 according to the present invention. Thus, compounds D1 to D9 according to the present invention exhibited high solubility for mesitylene compared to comparative compound C1. From this, it is believed that the nitrogen-containing condensed ring compounds according to the present invention have a high aggregation inhibitory effect due to specific substituents. On the other hand, it is believed that comparative compound C does not have a high aggregation inhibitory effect due to specific substituents. [Evaluation of Compounds by Calculation 4]

[0948] For some of the nitrogen-containing condensed ring compounds 1 to 317 exemplified in the description of the nitrogen-containing condensed ring compounds according to the present invention above, the dihedral angle between the group derived from the aromatic ring that is bonded to the core through a single bond and the group derived from the aromatic ring that is bonded to the core through a single bond was calculated using GaussView (Gaussian Inc.) from the most stabilized structure calculated according to the calculation method of (I) in the above “calculation by Density Functional Theory (DFT)”.

[0949] The dihedral angle of a ring having aromaticity that is bonded to a core and a core through a single bond, as discussed in this specification, is defined as the angle formed by triangle △α2α1β1 with vertices α2, α1, and β1 and triangle △β2β1α1 with vertices β2, β1, and α1, where α1 is the atom of the core bonded to the substituent, α2 is the atom closest to α1 in the core, β1 is the atom of the substituent bonded to the core, and β2 is the atom closest to β1 in the substituent.

[0950] More specifically, for nitrogen-containing condensed ring compounds, the dihedral angles of the core and the ring-derived from the aromatic ring bonded to the core via a single bond were calculated using Density Functional Theory (DFT) with Gaussian 16 (Gaussian Inc.) as the computational software, and using GaussView (Gaussian Inc.) from the most stabilized structure calculated according to the calculation method of (I) below:

[0951] (I) S0 calculation method: Structural optimization calculation by DFT including functional B3LYP, basis function 6-31 G(d, p), and toluene solvent effect (PCM).

[0952] The results of these evaluations are shown in Tables 13 to 18 below. Additionally, in these tables, dihedral angles 1 to 4 represent the dihedral angles between the group derived from the core and the group derived from the aromatic ring that is bonded to the core and the group derived from the other benzene ring in the core via a single bond, respectively. Furthermore, in these tables, "-" indicates that the group does not have a substituent including a group derived from the aromatic ring that is bonded to the core via a single bond to form the corresponding dihedral angle.

[0953] (Table 13) Evaluation results of the dihedral angle of a core part of a nitrogen-containing condensed ring compound and a tile derived from an aromatic ring bonded to the core part via a single bond.

[0954] Compound No. Dihedral angle 1[°] Dihedral angle 2[°] Dihedral angle 3[°] Dihedral angle 4[°] note 1 54.8 54.6 － － The present invention 2 53.9 53.7 － － The present invention 3 74.1 77.9 － － The present invention 4 49.5 49.9 － － The present invention 7 89.7 90.0 － － The present invention 11 89.9 89.9 － － The present invention 15 65.5 65.7 － － The present invention 16 64.2 64.2 － － The present invention 17 88.8 88.6 － － The present invention 18 67.1 67.5 － － The present invention 21 59.5 59.0 － － The present invention 24 55.4 54.9 － － The present invention 50 89.9 89.9 － － The present invention 51 83.3 81.0 － － The present invention 52 89.9 89.6 － － The present invention 53 75.8 75.8 － － The present invention 54 89.6 89.6 － － The present invention 55 89.4 89.4 － － The present invention 68 52.4 52.4 51.1 51.1 The present invention 69 89.8 89.8 89.8 89.8 The present invention 70 90.0 89.9 89.9 90.0 The present invention 71 89.9 89.8 89.4 89.9 The present invention 72 57.2 57.1 57.1 57.0 The present invention 83 51.1 57.1 52.6 52.2 The present invention 84 89.9 89.9 89.9 89.9 The present invention 85 89.9 89.8 89.9 89.8 The present invention 86 51.9 52.3 39.2 39.1 The present invention 87 53.4 52.7 39.1 38.9 The present invention 88 59.5 59.2 39.1 39.2 The present invention 89 55.4 55.2 38.9 38.9 The present invention 90 52.3 53.4 39.8 40.0 The present invention 91 53.0 53.1 38.3 39.7 The present invention 92 55.1 55.5 40.1 40.3 The present invention 93 57.7 57.7 39.7 38.0 The present invention 94 58.3 58.3 58.7 58.7 The present invention 95 55.8 54.3 54.3 54.5 The present invention

[0955] (Table 14) Evaluation results of the dihedral angle of a core part of a nitrogen-containing condensed ring compound and a tile derived from an aromatic ring bonded to the core part via a single bond.

[0956] Compound No. Dihedral angle 1[°] Dihedral angle 2[°] Dihedral angle 3[°] Dihedral angle 4[°] note 96 54.9 54.7 51.2 52.3 The present invention 97 54.4 55.1 52.1 50.1 The present invention 98 52.0 50.3 38.2 38.1 The present invention 99 51.9 50.3 37.3 37.1 The present invention 100 51.9 50.3 39.2 38.9 The present invention 101 51.4 50.5 38.8 39.0 The present invention 102 50.6 53.5 38.2 38.2 The present invention 103 50.6 51.3 40.0 40.0 The present invention 104 53.8 53.8 51.6 51.6 The present invention 106 53.3 51.3 51.3 53.3 The present invention 108 50.5 51.9 52.2 54.2 The present invention 109 55.2 55.8 － － The present invention 110 55.2 55.7 － － The present invention 114 60.7 60.9 － － The present invention 115 60.4 60.4 － － The present invention 116 51.4 49.8 － － The present invention 120 55.2 52.3 － － The present invention 121 51.3 53.3 － － The present invention 122 60.6 60.3 38.0 37.9 The present invention 123 60.3 60.2 37.9 38.1 The present invention 124 58.7 58.7 － － The present invention 125 58.3 58.5 － － The present invention 126 61.0 60.7 60.5 60.5 The present invention 127 61.1 60.9 60.6 60.7 The present invention 128 58.8 58.4 58.9 58.5 The present invention 129 60.9 60.7 38.6 38.7 The present invention 130 56.9 56.5 38.4 38.5 The present invention 131 56.8 56.7 － － The present invention 132 56.6 56.6 － － The present invention 133 59.3 59.1 － － The present invention 134 60.6 60.6 － － The present invention 135 61.1 60.9 － － The present invention 136 61.3 61.6 － － The present invention 140 57.9 57.9 － － The present invention 141 55.6 56.5 － － The present invention 142 60.3 58.2 － － The present invention 144 54.8 54.7 － － The present invention 145 51.3 49.3 － － The present invention 146 59.6 60.3 － － The present invention 147 51.2 51.2 － － The present invention 148 61.4 60.8 － － The present invention

[0957] (Table 15) Evaluation results of the dihedral angle of a core part of a nitrogen-containing condensed ring compound and a tile derived from an aromatic ring bonded to the core part via a single bond.

[0958] Compound No. Dihedral angle 1[°] Dihedral angle 2[°] Dihedral angle 3[°] Dihedral angle 4[°] note 149 60.2 60.2 39.2 38.7 The present invention 150 60.9 60.5 38.8 38.8 The present invention 151 60.7 60.8 39.7 40.0 The present invention 152 58.2 56.8 40.6 40.7 The present invention 153 82.6 82.5 － － The present invention 154 49.7 51.7 － － The present invention 155 52.0 50.7 － － The present invention 156 49.7 50.5 － － The present invention 157 60.1 60.0 － － The present invention 158 60.1 59.4 － － The present invention 159 60.5 61.1 － － The present invention 160 61.2 60.8 － － The present invention 194 79.0 79.3 － － The present invention 195 54.5 54.3 42.6 43.3 The present invention 196 60.3 60.2 － － The present invention 197 59.9 59.9 － － The present invention 198 60.0 59.9 － － The present invention 199 59.3 59.3 － － The present invention 200 60.0 59.8 － － The present invention 201 59.3 59.4 － － The present invention 202 58.7 58.4 － － The present invention 203 59.9 59.9 － － The present invention 204 60.4 60.3 － － The present invention 205 87.4 87.5 － － The present invention 206 58.9 58.7 － － The present invention 207 59.7 59.5 － － The present invention 208 60.1 60.0 － － The present invention 209 85.0 60.8 － － The present invention 210 89.6 89.8 － － The present invention 211 89.4 89.2 － － The present invention 212 67.1 67.1 － － The present invention 213 66.8 66.9 － － The present invention 214 67.8 67.9 － － The present invention 215 67.7 67.6 － － The present invention 216 68.1 70.0 － － The present invention 217 66.4 68.2 － － The present invention 218 50.5 － － － The present invention 221 64.9 － － － The present invention 222 54.5 － － － The present invention 225 63.9 － － － The present invention

[0959] (Table 16) Evaluation results of the dihedral angles of the core of a nitrogen-containing condensed ring compound and the tiles derived from an aromatic ring bonded to the core via a single bond.

[0960] Compound No. Dihedral angle 1[°] Dihedral angle 2[°] Dihedral angle 3[°] Dihedral angle 4[°] note 228 56.5 － － － The present invention 231 64.0 － － － The present invention 232 60.9 － － － The present invention 233 60.3 － － － The present invention 234 58.9 － － － The present invention 235 60.4 － － － The present invention 236 60.9 － － － The present invention 237 61.3 － － － The present invention 238 89.9 89.9 － － The present invention 239 90.0 90.0 － － The present invention 240 89.6 89.6 － － The present invention 241 86.0 86.0 － － The present invention 242 86.8 87.8 － － The present invention 243 88.8 88.8 － － The present invention 244 85.6 85.7 － － The present invention 245 87.0 87.1 － － The present invention 246 51.5 50.2 48.4 48.6 The present invention 248 80.5 80.4 48.1 48.0 The present invention 249 72.3 72.7 － － The present invention 250 70.0 70.0 44.0 44.4 The present invention 251 64.8 64.6 37.0 37.2 The present invention 252 55.0 54.0 39.2 39.3 The present invention 253 64.3 62.7 38.9 38.9 The present invention 254 79.0 79.1 38.1 38.1 The present invention 255 64.4 63.7 35.9 36.1 The present invention 256 53.9 55.0 38.3 38.4 The present invention 257 64.9 62.8 37.6 37.5 The present invention 258 79.1 79.1 37.3 37.3 The present invention 259 62.5 62.5 － － The present invention 260 54.7 54.7 － － The present invention 261 64.2 64.2 37.5 38.1 The present invention 262 64.5 64.5 42.4 42.9 The present invention 263 62.8 63.7 37.0 38.8 The present invention 264 63.4 63.4 37.4 37.4 The present invention 265 63.7 63.1 38.4 39.1 The present invention 266 68.0 62.1 48.7 53.0 The present invention 267 64.0 64.0 38.2 37.8 The present invention 268 64.2 64.2 38.0 38.1 The present invention 269 66.3 66.3 36.4 36.0 The present invention

[0961] (Table 17) Evaluation results of the dihedral angles of the core of a nitrogen-containing condensed ring compound and the tiles derived from an aromatic ring bonded to the core via a single bond.

[0962] Compound No. Dihedral angle 1[°] Dihedral angle 2[°] Dihedral angle 3[°] Dihedral angle 4[°] note 270 58.8 59.9 38.1 37.8 The present invention 271 88.7 62.9 44.8 42.1 The present invention 272 56.7 56.7 47.2 45.0 The present invention 273 59.3 59.3 38.3 38.3 The present invention 274 59.8 59.8 38.6 38.5 The present invention 275 68.4 68.2 52.6 52.5 The present invention 276 65.7 60.1 38.7 38.4 The present invention 277 59.9 59.8 37.8 38.3 The present invention 278 63.4 63.4 38.0 38.6 The present invention 279 62.7 62.7 38.1 38.0 The present invention 280 63.3 63.3 39.7 39.7 The present invention 281 56.3 56.4 39.3 39.2 The present invention 282 65.0 65.6 75.0 75.1 The present invention 283 56.9 70.4 61.3 59.4 The present invention 284 62.3 62.7 70.6 70.3 The present invention 285 64.4 65.6 47.3 49.8 The present invention 286 57.0 66.7 52.2 42.5 The present invention 287 66.6 65.1 79.1 52.4 The present invention 289 52.5 52.5 － － The present invention 291 54.9 54.9 － － The present invention 292 61.2 61.6 － － The present invention 293 62.2 62.2 － － The present invention 294 51.4 51.4 － － The present invention 295 61.5 61.5 － － The present invention 296 64.4 64.4 － － The present invention 297 62.7 62.7 － － The present invention 299 69.1 69.1 － － The present invention 300 65.2 64.6 － － The present invention 301 58.5 58.6 － － The present invention 303 56.2 56.2 － － The present invention 304 63.6 63.6 － － The present invention 305 57.0 57.0 － － The present invention 306 62.5 62.4 － － The present invention 308 88.5 88.7 － － The present invention 309 84.5 86.7 － － The present invention 310 86.9 86.9 － － The present invention 311 53.1 53.2 － － The present invention 312 85.6 87.2 － － The present invention 313 84.1 84.1 － － The present invention 314 48.9 50.6 － － The present invention

[0963] (Table 18) Evaluation results of the dihedral angles of the core of a nitrogen-containing condensed ring compound and the tiles derived from an aromatic ring bonded to the core via a single bond.

[0964] Compound No. Dihedral angle 1[°] Dihedral angle 2[°] Dihedral angle 3[°] Dihedral angle 4[°] note 315 63.1 63.1 － － The present invention 316 67.0 67.0 － － The present invention 317 62.6 62.7 － － The present invention

[0965] [Emission peak wavelength and full width at half maximum (FWHM) of the emission spectrum peak in photoluminescence (PL) in film state]

[0966] On a quartz substrate, compounds D1 to D8 obtained above are present at a mass ratio of 1 mass% with respect to the host compound mCBP (3,3'-bis(9H-carbazol-9-yl)-1,1'-biphenyl(3,3´-di(9H-carbazol-9-yl)-1,1´-biphenyl)) (compound H9 in the description of the host material above), 10 -5 A thin film with a thickness of 50 nm was prepared by co-depositing at a vacuum of Pa. Each emission spectrum of the prepared thin film was measured at room temperature with an excitation wavelength of 360 nm using a spectrofluorescence photometer F7000 manufactured by Hitachi High-Tech Corp., and the peak wavelength (nm) of the emission and the full width at half maximum (FWHM) of the peak of the emission spectrum were evaluated.

[0967] The results of these evaluations are shown in Table 19 below. In addition, Table 19 below indicates the change in the full width at half maximum (FWHM) of the emission spectrum peaks measured in the above solution state with respect to the full width at half maximum (FWHM) of the emission spectrum peaks. Furthermore, the "maximum value of the dihedral angle of the substituent substituting the core part" in Table 19 below represents the maximum value among dihedral angles 1 to 4 calculated by the above "Evaluation of Compounds by Calculation 4". If only one dihedral angle is calculated for the above "Evaluation of Compounds by Calculation 4", the "maximum value of the dihedral angle of the substituent substituting the core part" represents the value of the dihedral angle. Additionally, since compound C1 does not have a substituent containing a group derived from an aromatic ring that is bonded to the core part via a single bond, dihedral angles 1 to 4 cannot be calculated, and the "maximum value of the dihedral angle of the substituent substituting the core part" is indicated as "-".

[0968] (Table 19) Emission peak wavelength and full width at half maximum (FWHM) of emission spectra of nitrogen-containing condensed ring compounds

[0969] Compound No. Evaluation results by simulation Film condition evaluation results Evaluation results of the solution state note The maximum dihedral angle of the core part of the substitutional substitution [°] PL-induced luminescence peak wavelength [nm] Full Width at Half Mouth (FWHM) of the peak of the emission spectrum due to PL [nm] Full Width at Half Mouth (FWHM) of the peak of the emission spectrum due to PL [nm] D1 90.0 458 15 12 The present invention D7 60.9 462 18 16 The present invention D8 67.5 454 12 11 The present invention C1 － 454 22 13 Comparative example

[0970] From the results of Table 19 above, it can be understood that when the nitrogen-containing condensed ring compound according to the present invention has one or more substituents including a group derived from an aromatic ring that is bonded to the core through a single bond, the dihedral angle between the core and at least one group derived from an aromatic ring that is bonded to the core through a single bond can be 50° or more. That is, it was confirmed that for such a nitrogen-containing condensed ring compound, the difference between the full width at half maximum (FWHMM) of the emission spectrum in a solution state and the full width at half maximum (FWHMM) of the emission spectrum in a film state is reduced. From this, it is presumed that since such a nitrogen-containing condensed ring compound can obtain a small full width at half maximum (FWHMM) of the emission spectrum even in a film state, it can also obtain a small full width at half maximum (FWHM) of the emission spectrum for an organic electroluminescent device using it. <Fabrication of Organic Electroluminescent Devices (Organic EL Devices)>

[0971] [Fabrication of Organic EL Devices]

[0972] (Preparation of materials to form each layer)

[0973] In addition to the compound D1 and comparative compound C1 obtained above, the following materials were prepared as materials used for forming each layer of an organic EL device. Here, the following compounds H-H1, H-E1, and phosphorescent complex Pt1 are the same compounds as the compounds H55, H77, and phosphorescent complex P6 described above, respectively.

[0974]

[0975]

[0976] (Example 1)

[0977] An ITO glass substrate was cut to a size of 50mm x 50mm x 0.5mm and ultrasonically cleaned for 15 minutes each in the order of acetone, isopropyl alcohol, and pure water, followed by UV ozone cleaning for 30 minutes. The following layer was deposited on the ITO electrode (anode) on the glass substrate using a vacuum deposition apparatus.

[0978] First, F6-TCNNQ was deposited on the above ITO electrode to form a hole injection layer with a film thickness of 10 nm. Next, compound HT1 was deposited on the hole injection layer to form a hole transport layer with a film thickness of 126 nm. Subsequently, compound H-H1 was deposited on the hole transport layer to form an electron blocking layer with a film thickness of 10 nm. In this way, a hole transport region was formed.

[0979] Compound H-H1, compound H-E1, phosphorescent complex Pt1, and compound D1 obtained above were co-deposited on the hole transport region to form an emissive layer with a film thickness of 40 nm. The emissive layer was formed such that the mass ratio of compound H-H1, compound H-E1, and phosphorescent complex Pt1 in the emissive layer was compound H-H1:compound H-E1:phosphorescent complex Pt1 = 60:40:10. Additionally, the emissive layer was formed such that the concentration of compound D1 in the emissive layer was 0.5 mass% relative to the total mass of compound H-H1, compound H-E1, phosphorescent complex Pt1, and compound D1 (i.e., the total mass of the emissive layer). Furthermore, compound H-H1 and compound H-E1 are host materials.

[0980] Compound H-E1 was vacuum-deposited on the above-mentioned emissive layer to form a hole-blocking layer with a film thickness of 10 nm. Then, compound ET1 and LiQ were co-deposited on the hole-blocking layer in a mass ratio of compound ET1:LiQ = 5:5 (unit: parts by mass) to form an electron transport layer with a film thickness of 36 nm. Subsequently, LiQ was deposited on the electron transport layer to form an electron injection layer with a film thickness of 0.5 nm. In this way, an electron transport region was formed.

[0981] An organic EL device was fabricated by depositing an Al (cathode) with a film thickness of 80 nm on the electron injection layer.

[0982] Afterwards, the organic EL device produced by the above process was encapsulated using a glass encapsulation tube with a desiccant and a UV-curing resin (MORESCO product name WB90US) in a glove box with a nitrogen atmosphere having a moisture concentration of 1 ppm or less and an oxygen concentration of 1 ppm or less. In this way, the organic EL device was completed.

[0983] (Examples 2 and 3)

[0984] When forming the light-emitting layer, each organic EL device was fabricated and encapsulated in the same manner as in Example 1, except that the concentration of compound D1 in the light-emitting layer was changed to 1.5 mass% and 3.0 mass% with respect to the total mass of compound H-H1, compound H-E1, phosphorescent complex Pt1, and compound D1 (i.e., the total mass of the light-emitting layer), respectively.

[0985] (Example 4)

[0986] Each organic EL device was fabricated in the same manner as in Example 2, except that the phosphorescent complex Pt1 was not used when forming the light-emitting layer, and the organic EL device was completed by encapsulating it.

[0987] (Comparative Example 1)

[0988] Each organic EL device was fabricated and encapsulated in the same manner as in Example 2, except that the type of nitrogen-containing condensed ring compound was changed to comparative compound C1 when forming the light-emitting layer, thereby completing the organic EL device.

[0989] <Evaluation of Organic EL Devices 1>

[0990] [Luminance, External Quantum Efficiency, and Device Lifetime]

[0991] The results of evaluating brightness, external quantum efficiency, and device lifetime according to the following methods are shown in Table 20 below.

[0992] Using a DC constant voltage power supply (KEITHLEY source meter 2400 type), the organic EL element was induced to emit light while varying the applied voltage, and the luminance emission spectrum and amount of light emitted at that time were measured using a luminance measuring device (Topcon SR-3).

[0993] Here, the external quantum efficiency was calculated from the emission spectrum emission amount and the current value during measurement.

[0994] In addition, the device lifespan (durability) is based on an initial brightness of 1000 cd / m² 2 The device was driven continuously at a current value, and the time until the luminous brightness, which decays over time, reached 50% of the initial brightness was measured as “LT50”. LT95 in Table 20 below represents an absolute value (unit: hours (hrs)) and a relative value with LT50 [hr] (LT50(hrs)) of Example 4 set to 1. Additionally, the device lifespan of Example 4 was 1 hour.

[0995] [Emission peak wavelength and full width at half maximum (FWHM) of the emission spectrum]

[0996] The emission peak wavelength and the full width at half maximum (FWHM) of the emission spectrum peak were read from the measurement results of the emission spectrum.

[0997] In this evaluation, it was determined that a smaller full width at half maximum (FWHM) of the peak of the emission spectrum is desirable, and that if it is 30 nm or less, it indicates high color purity, and if it is 25 nm or less, it indicates particularly excellent high color purity.

[0998] In addition, in this evaluation, the emission peak wavelength may be 450 nm or more and 470 nm or less, and specifically, 450 nm or more and 465 nm or less.

[0999] (Table 20) Composition and evaluation results of the light-emitting layer of each organic EL device

[1000] Organic EL device composition of the light-emitting layer Evaluation results of organic EL devices nitrogen-containing heterocyclic compounds phosphorescent complex Luminance [Cd / m 2 ] External Quantum Efficiency [%] Emission peak wavelength [nm] Full Width of the Emission Spectrum (FWHM) LT50 type density[%] Concentration [%] Example 1 D1 0.5 9 1000 6.20 458 19 14.0 Example 2 D1 1.5 9 1000 4.42 459 20 10.5 Example 3 D1 3.0 9 1000 3.19 459 22 7.5 Example 4 D1 1.5 0 1000 2.57 459 19 1 Comparative Example 1 C1 1.5 9 1000 2.45 456 41 -

[1001] As shown in Table 20 above, it was confirmed that the organic EL devices of Examples 1 to 4 using nitrogen-containing condensed ring compounds according to the present invention achieve a good blue light emission color, and that the full width at half maximum (FWHM) of the peaks in the emission spectrum from the organic EL devices is narrow, and that light emission with high color purity is achieved. In addition, it was confirmed that the organic EL devices of Examples 1 to 4 using nitrogen-containing condensed ring compounds according to the present invention also have excellent external quantum efficiency. On the other hand, it was confirmed that the organic EL device of Comparative Example 1 using a nitrogen-containing condensed ring compound with a structure outside the scope of the present invention has a wide full width at half maximum (FWHM) of the peaks in the emission spectrum and is inferior in color purity. In addition, as shown in Table 20 above, in a comparison of organic EL devices using the same nitrogen-containing condensed ring compound, it was confirmed that the organic EL devices using the nitrogen-containing condensed ring compound according to the present invention in combination with the phosphorescent complex of Examples 1 to 3 had higher external quantum efficiency and longer device lifespan compared to the organic EL device not using the phosphorescent complex of Example 4. In addition, as shown in Tables 10 and 20 above, in a comparison of these devices with the organic EL device of Comparative Example 1, it was confirmed that the organic EL devices of Examples 1 to 3 had higher external quantum efficiency compared to the organic EL device of Comparative Example 1. Furthermore, as shown in Examples 1 to 3, it was confirmed that the external quantum efficiency of the organic EL device can be further improved by adjusting the concentration of the nitrogen-containing condensed ring compound. Here, the organic EL devices of Examples 1 to 3 are organic EL devices using the nitrogen-containing condensed ring compound and the phosphorescent complex in combination, satisfying all of the above conditions (i) to (iv) according to the present invention. In addition, the organic EL device of Comparative Example 1 is a structure outside the scope of the present invention, and is an organic EL device that uses a phosphorescent complex with a comparative compound C1, which is considered not to satisfy condition (iii) and not to have TADF characteristics.

[1002] In addition, as shown in Examples 1 to 4 of Table 20 above, it was confirmed that the nitrogen-containing condensed ring compound according to the present invention achieves a good blue emission color even at high dopant concentrations, and also achieves high color purity emission with a narrow full width at half maximum (FWHM) of the peak of the emission spectrum from an organic EL device. This is presumed to be based on the aggregation inhibition effect of the substituents of the nitrogen-containing condensed ring compound according to the present invention.

[1003] In addition, as shown in Table 12 above, compounds D1 to D14 according to the present invention exhibited high solubility in mesitylene compared to comparative compound C1. From this, it is believed that the nitrogen-containing condensed ring compounds according to the present invention have a high aggregation inhibitory effect due to specific substituents.

[1004] In addition, as shown in Table 11 above, it was confirmed that other compounds D2 to D14 according to the present invention exhibit a good blue emission color in PL, similar to compound D1 according to the present invention, and that high color purity emission is realized. In addition, as shown in Table 12 above, it was confirmed that other compounds D2 to D14 according to the present invention exhibit high solubility in mesitylene, similar to compound D1 according to the present invention. From this, it is presumed that compounds D2 to D14 according to the present invention, similar to compound D1 according to the present invention, exhibit a good blue emission color in organic EL devices and that high efficiency and high color purity emission are realized. Furthermore, it is presumed that a long lifespan is realized when used in combination with a phosphorescent complex in organic EL devices.

[1005] In addition, as shown in Table 11 above, the emission peak wavelength in the PL of Comparative Compound C1 is blue, and the full width at half maximum (FWHM) of the peak in the PL of Comparative Compound C1 is narrow, and high color purity emission is realized. From this, it is believed that the blue emission color and good high color purity emission are attributed to the specific nitrogen-containing condensed ring structure that serves as the matrix. However, as shown in Table 20 above, the full width at half maximum (FWHM) of the peak in the emission spectrum of the organic EL device of Comparative Example 1 using Comparative Compound C1 is wide, and the color purity is inferior. It is speculated that this is because Comparative Compound C1 does not have a high aggregation inhibition effect due to the specific substituent as described above, so emission occurs from aggregates. From this, it is presumed that a nitrogen-containing condensed ring compound having a specific nitrogen-containing condensed ring structure as a matrix and a specific substituent for said structure, represented by the structure (1) according to the present invention, exhibits the excellent effects of the present invention, similar to compound D1 according to the present invention.

[1006] <Fabrication of Organic Electroluminescent Devices (Organic EL Devices) 2>

[1007] [Fabrication of Organic EL Devices]

[1008] (Example 5)

[1009] Organic EL devices were fabricated in the same manner as in Example 1 by changing various materials used. The procedure is described below.

[1010]

[1011] An ITO glass substrate was cut to a size of 50 mm × 50 mm × 0.5 mm, ultrasonically cleaned with acetone, isopropyl alcohol, and pure water for 15 minutes each, followed by UV ozone cleaning for 30 minutes. The following layer was deposited on the ITO electrode (anode) on the glass substrate using a vacuum deposition apparatus.

[1012] First, HAT-CN (prepared by e-Ray) was deposited on an ITO electrode to form a hole injection layer with a film thickness of 10 nm. Subsequently, compound HT1 was deposited on the hole injection layer to form a hole transport layer with a film thickness of 125 nm. Then, compound H-H2 was deposited on the hole transport layer to form an electron blocking layer with a film thickness of 10 nm. In this way, a hole transport region was formed.

[1013] A light-emitting layer with a film thickness of 40 nm was formed by co-depositing compound H-H2, compound H-E1, phosphorescent complex Pt2, and the obtained compound D3 on the hole transport region. Here, the film was formed such that the mass ratio of compound H-H2, compound H-E1, and phosphorescent complex Pt2 in the light-emitting layer was compound H-H2:compound H-E1:phosphorescent complex Pt2 = 60:40:10. In addition, the film was formed such that the concentration of compound D3 in the light-emitting layer was 0.5 mass% relative to the total mass of compound H-H2, compound H-E1, phosphorescent complex Pt2, and compound D3 (i.e., the total mass of the light-emitting layer). Furthermore, compound H-H2 and compound H-E1 are host materials.

[1014] A hole blocking layer with a film thickness of 10 nm was formed by vacuum depositing compound H-E1 on the above-mentioned light-emitting layer. Subsequently, an electron transport layer with a film thickness of 30 nm was formed by co-depositing compound ET1 and LiQ on the above-mentioned hole blocking layer in a mass ratio of compound ET1:LiQ = 5:5 (unit: parts by mass). Subsequently, an electron injection layer with a film thickness of 1 nm was formed by depositing LiQ on the above-mentioned electron transport layer. In this way, an electron transport region was formed. An organic EL device was fabricated by depositing Al (cathode) with a film thickness of 80 nm on the above-mentioned electron injection layer.

[1015] Subsequently, the organic EL device produced by the above process was sealed in a glove box with a nitrogen atmosphere having a moisture concentration of 1 ppm or less and an oxygen concentration of 1 ppm or less, using a glass sealing tube attached with a desiccant and a UV-curing resin (MORESCO, product name WB90US). In this way, the organic EL device was completed.

[1016] (Examples 6 to 9)

[1017] In the formation of the light-emitting layer, each organic EL device was fabricated and sealed in the same manner as in Example 5, except that the type of nitrogen-containing condensed ring compound was changed from D3 to D4, D5, D6, and D7, respectively, to complete the organic EL device.

[1018] (Comparative Example 2)

[1019] In the formation of the light-emitting layer, each organic EL device was fabricated and sealed in the same manner as in Example 5, except that the type of nitrogen-containing condensed ring compound was changed from D3 to comparative compound C1, and the organic EL device was completed.

[1020] <Evaluation of Organic EL Devices 2>

[1021] [Luminance, External Quantum Efficiency, and Device Lifetime]

[1022] The results of evaluating the same items as Evaluation 1 of the above organic EL devices for the organic EL devices of Examples 5 to 9 and Comparative Example 2 obtained are shown in Table 21 below.

[1023] Luminance, external quantum efficiency, emission peak wavelength, and full width at half maximum (FWHM) of the emission spectrum were evaluated by measuring in the same manner as in Evaluation 1 of the organic EL device described above. Device lifetime was determined at an initial luminance of 1,000 cd / m² 2Except for continuous driving at a current value and measuring the time until the luminous brightness, which decays over time, reaches 95% of the initial brightness as "LT95," the measurement was performed in the same manner as the method of Evaluation 1 of the above organic EL device. The LT95 in Table 21 below represents an absolute value (unit: time (hrs)).

[1024] (Table 21) Composition and evaluation results of the light-emitting layer of each organic EL device

[1025] Organic EL device Composition of the light-emitting layer Evaluation results of organic EL devices nitrogen-containing heterocyclic compounds phosphorescent complex Luminance [Cd / m²] 2 ] External Quantum Efficiency[%] Emission peak wavelength [nm] Full Width at Half Maximum (FWHM) of the emission spectrum peak [nm] LT[hrs] type Concentration [Mass %] Concentration [Mass %] Example 5 D3 0.5 9 1000 11.8 463 21 14.4 Example 6 D4 0.5 9 1000 13.3 466 22 28.2 Example 7 D5 0.5 9 1000 14.2 465 24 29.4 Example 8 D6 0.5 9 1000 15.3 468 25 34.6 Example 9 D7 0.5 9 1000 13.5 462 22 13.4 Comparative Example 2 C1 0.5 9 1000 3.6 454 21 1

[1026] As shown in Table 21 above, it was confirmed that the organic EL devices of Examples 5 to 9, which use nitrogen-containing condensed ring compounds according to the present invention, exhibit a narrow full width at half maximum (FWHM) of the peaks in the emission spectrum, realize high color purity emission, have excellent external quantum efficiency, and have a long device lifespan. On the other hand, it was confirmed that the organic EL device of Comparative Example 2, which uses a nitrogen-containing condensed ring compound with a structure outside the scope of the present invention, has low external quantum efficiency and a short device lifespan. Furthermore, in Table 21 above, the organic EL device of Comparative Example 2, which uses Comparative Compound C1, exhibits a narrow full width at half maximum (FWHM) of the peaks in the emission spectrum and obtains high color purity emission. It is presumed that this is because aggregates are difficult to form when the concentration of the nitrogen-containing condensed ring compound is low. However, the organic EL device of Comparative Example 2 showed inferior results in external quantum efficiency and device lifespan. Meanwhile, the organic EL devices of Examples 5 to 9 using the nitrogen-containing condensed ring compound of the present invention show significantly improved external quantum efficiency and device lifespan compared to the organic EL device of Comparative Example 2. It is presumed that this is because introducing specific substituents at specific positions suppresses intermolecular aggregation and simultaneously suppresses intermolecular interactions with other compounds constituting the light-emitting layer, thereby reducing non-luminous components and contributing to the improvement of external quantum efficiency and device lifespan.

[1027] <Fabrication of Organic Electroluminescent Devices (Organic EL Devices) 3>

[1028] [Fabrication of Organic EL Devices]

[1029] (Examples 10, 11)

[1030] Various materials were changed, and organic EL devices were fabricated using the same method as in Example 1. The fabrication procedure is described below.

[1031]

[1032] An ITO glass substrate was cut into pieces measuring 50 mm × 50 mm × 0.5 mm, ultrasonically cleaned with acetone, isopropyl alcohol, and pure water for 15 minutes each, and then UV ozone cleaned for 30 minutes. The following layers were deposited on the ITO electrode (anode) on the glass substrate using a vacuum deposition apparatus.

[1033] First, HAT-CN (e-Ray agent) was deposited on the ITO electrode to form a hole injection layer with a film thickness of 10 nm. Subsequently, compound HT1 was deposited on the hole injection layer to form a hole transport layer with a film thickness of 140 nm. Then, compound H-H3 was deposited on the hole transport layer to form an electron blocking layer with a film thickness of 5 nm. In this way, a hole transport region was formed.

[1034] A light-emitting layer with a film thickness of 40 nm was formed by co-depositing compound H-H3, a host material (HT-Host compound) having hole transport properties, mSiTrz (manufactured by LUMTEC), a host material (ET-Host compound) having electron transport properties, phosphorescent complex Pt2, and the obtained compound D5 on the hole transport region. Here, the mass ratio of compound H-H3 and mSiTrz in the light-emitting layer was formed as shown in Table 22 below. In addition, the film was formed such that the concentration of phosphorescent complex Pt2 in the light-emitting layer was 7 mass% relative to the total mass of compound H-H3, mSiTrz, phosphorescent complex Pt2, and compound D5 (i.e., the total mass of the light-emitting layer), and the concentration of compound D5 in the light-emitting layer was 0.2 mass% relative to the total mass of compound H-H3, mSiTrz, phosphorescent complex Pt2, and compound D5 (i.e., the total mass of the light-emitting layer). Additionally, compounds H-H3 and mSiTrz are host materials.

[1035] A hole blocking layer with a film thickness of 5 nm was formed by vacuum depositing mSiTrz on the above-mentioned light-emitting layer. Subsequently, an electron transport layer with a film thickness of 30 nm was formed by co-depositing TRE314 (manufactured by Tore Corporation, electron transport material) and LiQ on the above-mentioned hole blocking layer in a mass ratio of TRE314:LiQ = 5:5 (unit: parts by mass). Subsequently, an electron injection layer with a film thickness of 1 nm was formed by depositing LiQ on the above-mentioned electron transport layer. In this way, an electron transport region was formed.

[1036] An organic EL device was fabricated by depositing an Al (cathode) with a film thickness of 100 nm on the electron injection layer.

[1037] Afterwards, the organic EL device produced by the above process was encapsulated using a glass encapsulation tube with a desiccant attached and a UV-curing resin (MORESCO, product name WB90US) in a glove box with a nitrogen atmosphere having a moisture concentration of 1 ppm or less and an oxygen concentration of 1 ppm or less. In this way, the organic EL device was completed.

[1038] (Examples 12, 13)

[1039]

[1040] In Example 10, each organic EL device was fabricated and sealed in the same manner as in Example 10, except that the ET-Host compound in the film formation of the light-emitting layer was changed from mSiTrz to H-E2, the material used in the film formation of the hole blocking layer was changed from mSiTrz to H-E2, and the mass ratio of the compound H-H3 and mSiTrz in the light-emitting layer was set as shown in Table 22 below.

[1041] <Evaluation of Organic EL Devices 3>

[1042] [Luminance, External Quantum Efficiency, and Device Lifetime]

[1043] The results of evaluating the same items as Evaluation 1 of the above organic EL devices for the organic EL devices of Examples 10 to 13 obtained are shown in Table 22 below.

[1044] Luminance, external quantum efficiency, emission peak wavelength, and full width at half maximum (FWHM) of the emission spectrum were evaluated by measuring in the same manner as in Evaluation 1 of the organic EL device described above. Device lifetime was determined at an initial luminance of 1,000 cd / m² 2 Except for continuous driving at a current value and measuring the time until the luminous brightness decaying over time reaches 95% of the initial brightness as "LT95," the measurement was performed in the same manner as the method of Evaluation 1 of the above organic EL device. The LT95 in Table 22 below represents an absolute value (unit: time (hrs)).

[1045] (Table 22) Composition and evaluation results of the light-emitting layer of each organic EL device

[1046] Organic EL device Composition of the light-emitting layer Ratio of host ingredients nitrogen-containing heterocyclic compounds Phosphorescent complex Pt2 Compound H-H3 : ET-Host Compound [Mass Ratio] type Concentration [Mass %] Concentration [Mass %] Example 10 8.5:1.5 D5 0.2 7 Example 11 8:2 D5 0.2 7 Example 12 7.5:2.5 D5 0.2 7 Example 13 7:3 D5 0.2 7 Organic EL device Evaluation results of organic EL devices Luminance [Cd / m²] 2 ] External Quantum Efficiency[%] Emission peak wavelength [nm] Full Width at Half Maximum (FWHM) of the emission spectrum peak [nm] LT[hrs] Example 10 1000 11.5 463 18.8 10.5 Example 11 1000 11.2 463 19.6 17.0 Example 12 1000 10.3 464 22.5 19.4 Example 13 1000 10.5 464 22.5 17.5

[1047] As shown in Table 22 above, in the organic EL devices of Examples 10 and 11, in which a nitrogen-containing condensed ring compound according to the present invention and a compound having a triazine ring structure with a silyl group are used in combination as host materials, it was confirmed that the full width at half maximum (FWHM) of the emission spectrum is even narrower, high color purity emission is realized, and the external quantum efficiency is also excellent. It was also confirmed that the device lifespan is long. As such, the nitrogen-containing condensed ring compounds according to the present invention, including compounds D1 to D7, exhibited a precisely tuned blue emission color, good high color purity, and high luminous efficiency in organic EL devices. In particular, when used in combination with phosphorescent materials, a significant improvement in device lifespan was observed. These results are thought to sufficiently satisfy the specifications required for future wide color gamut devices such as BT2020, and enable the realization of high-definition next-generation displays.

[1048] Although the present invention has been described with reference to embodiments and examples, the present invention is not limited to specific embodiments and examples, and various modifications and changes are possible within the scope of the invention as described in the claims. Explanation of the symbols

[1049] 1: Substrate 2: First electrode 3: Hole transport zone 31: Hole injection layer 32: Hole transport layer 33: Electron blocking layer 4: Emissive layer 5: Electron transport region 51: Electron injection layer 52: Electron transport layer 53 : Hole blocking layer 6 : Second electrode 10 : Organic electroluminescent device.

Claims

Claim 1 delete Claim 2 delete Claim 3 delete Claim 4 delete Claim 5 delete Claim 6 delete Claim 7 delete Claim 8 A material for an organic electroluminescent device comprising a nitrogen-containing condensed ring compound having a structure represented by any of the following formulas (3-1) to (3-9) and a phosphorescent complex: Claim 9 delete Claim 10 A material for an organic electroluminescent device comprising a nitrogen-containing condensed ring compound having a structure selected from the group consisting of the following formulas (12) to (14) and a phosphorescent complex: In the above formulas (12) to (14), A 201 To A 204 is an independently unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted monovalent aromatic hydrocarbon group, or a substituted or unsubstituted monovalent aromatic heterocyclic group, and R 201 and R 202 is independently a halogen atom, a cyano group, an unsubstituted alkyl group having 1 to 20 carbon atoms, an unsubstituted haloalkyl group having 1 to 20 carbon atoms, an unsubstituted alkoxy group having 1 to 20 carbon atoms, an unsubstituted alkyl amino group having 1 to 20 carbon atoms, an unsubstituted aryl amino group having 6 to 20 carbon atoms, a substituted or unsubstituted monovalent aromatic hydrocarbon group, or a substituted or unsubstituted monovalent aromatic heterocyclic group, and R 203 and R 204 are independently a halogen atom, a cyano group, an unsubstituted alkyl group having 1 to 20 carbon atoms, an unsubstituted haloalkyl group having 1 to 20 carbon atoms, an unsubstituted alkoxy group having 1 to 20 carbon atoms, an unsubstituted haloalkoxy group having 1 to 20 carbon atoms, or an unsubstituted aryl amino group having 6 to 20 carbon atoms, and n201 and n202 are independently 0, 1, 2, 3, 4, or 5, and n203 and n204 are independently 0, 1, 2, 3, or 4, where each A 201 may be the same or different, and each A 202 may be the same or different, and each A 203 may be the same or different, and each A 204 may be the same or different, and 2 or more A 201 , 2 or more A 202 , 2 or more A 203 , 2 or more A 204 Each can form a ring, and also, if n201 is 2 or greater, each R 201 may be the same or different, and if n202 is 2 or greater, each R 202 may be the same or different, and if n203 is 2 or greater, each R 203 may be the same or different, and if n204 is 2 or greater, each R 204 may be the same or different, and in the above formula (12), each A 201 , each A 202 , each A 203 , each A 204 Each is not entirely an unsubstituted alkyl group having 1 to 20 carbon atoms, and in the above formula (13), each A 202 , each A 204 Each is not entirely an unsubstituted alkyl group having 1 to 20 carbon atoms, and in the above formula (14), each A 201 , each A 203 Each of them is not an unsubstituted alkyl group having 1 to 20 carbon atoms. Claim 11 delete Claim 12 delete Claim 13 In claim 10, the above-mentioned nitrogen-containing condensed ring compound is a material for an organic electroluminescent device satisfying all of the following conditions (i) to (iv): <condition (i)>ΔE ST > ΔE ST2 + ΔE' TT <Condition (ii)>0 eV < ΔE ST2 + ΔE' TT ≤ 1.0 eV<condition (iii)>0 eV<ΔE' TT ≤ 0.15 eV<condition (iv)>ΔE ST2 > 0 eV Under conditions (i) to (iv) above, ΔE ST (eV) represents the value of the difference between the lowest singlet excitation energy (eV) calculated for the S1 equilibrium structure and the lowest triplet excitation energy (eV) calculated for the T1 equilibrium structure; ΔE ST2 (eV) represents the value of the difference between the lowest singlet excitation energy (eV) calculated for the S1 equilibrium structure and the second lowest triplet excitation energy (eV) calculated for the T2 equilibrium structure; ΔE' TT (eV) represents the value of the difference between the second lowest triplet excitation energy (eV) calculated for a T2 equilibrium structure and the lowest triplet excitation energy (eV) calculated for a T2 equilibrium structure. Claim 14 In claim 10, the above nitrogen-containing condensed ring compound is a material for organic electroluminescent devices having a solubility in mesitylene of 1.0 g / L or more. Claim 15 In claim 10, the above phosphorescent complex is a platinum complex, a material for an organic electroluminescent device. Claim 16 A material for an organic electroluminescent device, comprising a host material in addition to the 10th item. Claim 17 In claim 16, the above host material is a material for an organic electroluminescent device comprising a compound having a structure represented by the following formula (5): In the above equation (5), Z 51 is CH, CR 51 or N and Z 52 is CH, CR 52 or N and Z 53 is CH, CR 53 or N and Z 54 is CH, CR 54 or N and Z 55 is CH, CR 55 or N and Z 56 is CH, CR 56 or N and Z 57 is CH, CR 57 or N and Z 58 is CH, CR 58 or N and, R 51 to R 58 is independently one of the following groups (5a) to (5h): (5a) a cyano group, (5b) a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, (5c) a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, (5d) a substituted or unsubstituted aryl amino group having 6 to 20 carbon atoms, (5e) a substituted or unsubstituted phosphoryl group (-POH2 group), (5f) a substituted or unsubstituted silyl group (-SiH3 group), (5g) a substituted or unsubstituted monovalent aromatic hydrocarbon group, (5h) a substituted or unsubstituted monovalent heterocyclic group, Ar 51 is a group comprising at least one of an aromatic hydrocarbon group and a heterocyclic group, m is 1, 2, 3, 4, 5 or 6, where R 51 and the above R 52 , above R 52 and the above R 53 , above R 53 and the above R 54 , above R 55 and the above R 56 , above R 56 and the above R 57 or the above R 57 and the above R 58 Each can form an aliphatic hydrocarbon ring, an aromatic hydrocarbon ring, or a heterocyclic ring containing a carbon atom bonded to it. Claim 18 In claim 16 or 17, the above host material is a material for an organic electroluminescent device comprising a compound having a structure represented by the following formula (6): In the above equation (6), Ar 61 or Ar 63 They are independently substituted or unsubstituted monovalent aromatic hydrocarbon groups or substituted or unsubstituted monovalent heterocyclic groups. Claim 19 delete Claim 20 delete Claim 21 delete Claim 22 delete Claim 23 delete Claim 24 delete Claim 25 delete Claim 26 A nitrogen-containing condensed ring compound having a structure represented by a formula selected from the group consisting of the following formulas (12) to (14), satisfying all of the following conditions (i) to (iv): In the above formulas (12) to (14), A 201 To A 204 is an independently unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted monovalent aromatic hydrocarbon group, or a substituted or unsubstituted monovalent aromatic heterocyclic group, and R 201 and R 202 is independently a halogen atom, a cyano group, an unsubstituted alkyl group having 1 to 20 carbon atoms, an unsubstituted haloalkyl group having 1 to 20 carbon atoms, an unsubstituted alkoxy group having 1 to 20 carbon atoms, an unsubstituted alkyl amino group having 1 to 20 carbon atoms, an unsubstituted aryl amino group having 6 to 20 carbon atoms, a substituted or unsubstituted monovalent aromatic hydrocarbon group, or a substituted or unsubstituted monovalent aromatic heterocyclic group, and R 203 and R 204 are independently a halogen atom, a cyano group, an unsubstituted alkyl group having 1 to 20 carbon atoms, an unsubstituted haloalkyl group having 1 to 20 carbon atoms, an unsubstituted alkoxy group having 1 to 20 carbon atoms, an unsubstituted haloalkoxy group having 1 to 20 carbon atoms, or an unsubstituted aryl amino group having 6 to 20 carbon atoms, and n201 and n202 are independently 0, 1, 2, 3, 4, or 5, and n203 and n204 are independently 0, 1, 2, 3, or 4, where each A 201 may be the same or different, and each A 202 may be the same or different, and each A 203 may be the same or different, and each A 204 may be the same or different, and 2 or more A 201 , 2 or more A 202 , 2 or more A 203 , 2 or more A 204 Each can form a ring, and also, if n201 is 2 or greater, each R 201 may be the same or different, and if n202 is 2 or greater, each R 202 may be the same or different, and if n203 is 2 or greater, each R 203 may be the same or different, and if n204 is 2 or greater, each R 204 may be the same or different, and in the above formula (12), each A 201 , each A 202 , each A 203 , each A 204 Each is not entirely an unsubstituted alkyl group having 1 to 20 carbon atoms, and in the above formula (13), each A 202 , each A 204 Each is not entirely an unsubstituted alkyl group having 1 to 20 carbon atoms, and in the above formula (14), each A 201 , each A 203 Each is not entirely an unsubstituted alkyl group having 1 to 20 carbon atoms, and <condition (i)> ΔE ST > ΔE ST2 + ΔE' TT <Condition (ii)>0 eV < ΔE ST2 + ΔE' TT ≤ 1.0 eV<condition (iii)>0 eV<ΔE' TT ≤ 0.15 eV<condition (iv)>ΔE ST2 > 0 eV Under conditions (i) to (iv) above, ΔE ST (eV) represents the value of the difference between the lowest singlet excitation energy (eV) calculated for the S1 equilibrium structure and the lowest triplet excitation energy (eV) calculated for the T1 equilibrium structure; ΔE ST2 (eV) represents the value of the difference between the lowest singlet excitation energy (eV) calculated for the S1 equilibrium structure and the second lowest triplet excitation energy (eV) calculated for the T2 equilibrium structure; ΔE' TT (eV) represents the value of the difference between the second lowest triplet excitation energy (eV) calculated for a T2 equilibrium structure and the lowest triplet excitation energy (eV) calculated for a T2 equilibrium structure. Claim 27 delete Claim 28 In claim 26, a nitrogen-containing condensed ring compound, wherein the structure represented by the above formulas (12) to (14) is a structure represented by one of the following formulas (3-1) to (3-9): Claim 29 delete Claim 30 delete Claim 31 In paragraph 26, a nitrogen-containing condensed ring compound having a solubility in mesitylene of 1.0 g / L or more. Claim 32 An organic electroluminescent device comprising a material for an organic electroluminescent device according to claim 8 or 10. Claim 33 An organic electroluminescent device comprising a nitrogen-containing condensed ring compound according to paragraph 26. Claim 34 An organic electroluminescent device comprising the above-mentioned nitrogen-containing condensed ring compound and a host material in paragraph 33. Claim 35 In paragraph 34, the above host material is an organic electroluminescent device comprising a compound having a structure represented by the following formula (5): In the above equation (5), Z 51 is CH, CR 51 or N and Z 52 is CH, CR 52 or N and Z 53 is CH, CR 53 or N and Z 54 is CH, CR 54 or N and Z 55 is CH, CR 55 or N and Z 56 is CH, CR 56 or N and Z 57 is CH, CR 57 or N and Z 58 is CH, CR 58 or N and, R 51 to R 58 is independently one of the following groups (5a) to (5h): (5a) a cyano group, (5b) a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, (5c) a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, (5d) a substituted or unsubstituted aryl amino group having 6 to 20 carbon atoms, (5e) a substituted or unsubstituted phosphoryl group (-POH2 group), (5f) a substituted or unsubstituted silyl group (-SiH3 group), (5g) a substituted or unsubstituted monovalent aromatic hydrocarbon group, (5h) a substituted or unsubstituted monovalent heterocyclic group, Ar 51 is a group comprising at least one of an aromatic hydrocarbon group and a heterocyclic group, m is 1, 2, 3, 4, 5 or 6, where R 51 and the above R 52 , above R 52 and the above R 53 , above R 53 and the above R 54 , above R 55 and the above R 56 , above R 56 and the above R 57 or the above R 57 and the above R 58 Each can form an aliphatic hydrocarbon ring, an aromatic hydrocarbon ring, or a heterocyclic ring containing a carbon atom bonded to it. Claim 36 In paragraph 34, the above host material is an organic electroluminescent device comprising a compound having a structure represented by the following formula (6): In the above equation (6), Ar 61 or Ar 63 They are independently substituted or unsubstituted monovalent aromatic hydrocarbon groups or substituted or unsubstituted monovalent heterocyclic groups. Claim 37 In claim 32, an organic electroluminescent device comprising a light-emitting layer, wherein the light-emitting layer comprises a material for the organic electroluminescent device.

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