Organic electroluminescent element

Abstract

Provided is a practically useful organic electroluminescent element having low voltage, high efficiency, and long life characteristics. Specifically, the organic electroluminescent element includes a light-emitting layer containing a first host that is an indolocarbazole derivative represented by general formula (1), a second host that is a dicarbazole derivative represented by general formula (2), and a light-emitting dopant material. (Ring G is represented by formula (1a), Ring H is represented by formula (1b), L1 is a single bond or the like, X is N or the like, Ar1 and Ar2 are aromatic hydrocarbon groups, aromatic hetero groups or the like and at least one is phenyl dibenzofuranyl groups or the like, and R1 and R2 are deuterium or the like. ) (Ar3 and Ar4 are aromatic hydrocarbon groups or the like, L is a single bond or the like, and R3, R6 and R7 are deuterium or the like. > # imgabs0 #

Description

Technical Field

[0001] The present invention relates to an organic electroluminescent element (hereinafter referred to as an organic EL element), and more particularly to an organic EL element including a specific mixed host material. Background Art

[0002] By applying voltage to the organic EL (electroluminescence) element, holes are injected from the anode into the light-emitting layer, and electrons are injected from the cathode into the light-emitting layer. In addition, in the light-emitting layer, the injected holes recombine with the electrons to generate excitons. At this time, according to the statistical law of electron spin, singlet excitons and triplet excitons are generated in a ratio of 1:3. Regarding fluorescent organic EL elements using light generated by singlet excitons, the limit of the internal quantum efficiency is considered to be 25%. On the other hand, it is known that phosphorescent organic EL elements using light generated by triplet excitons can increase the internal quantum efficiency to 100% when intersystem crossing is efficiently performed from singlet excitons.

[0003] Recently, a highly efficient organic EL element utilizing delayed fluorescence is being developed. For example, Patent Document 1 discloses an organic EL element utilizing a triplet-triplet fusion (TTF) mechanism, which is one of the mechanisms of delayed fluorescence. The TTF mechanism utilizes the phenomenon of generating singlet excitons by the collision of two triplet excitons, and is believed to theoretically increase the internal quantum efficiency to 40%. However, when compared with a phosphorescent organic EL element, the efficiency is low, and therefore further improvements in efficiency and low voltage characteristics are required.

[0004] In addition, Patent Document 2 discloses an organic EL element that utilizes the thermally activated delayed fluorescence (TADF) mechanism. The TADF mechanism utilizes the following phenomenon: in a material with a small energy difference between the singlet energy level and the triplet energy level, reverse intersystem crossing from triplet excitons to singlet excitons occurs; it is believed that the internal quantum efficiency can be increased to 100% in theory.

[0005] However, in any mechanism, there is room for improvement in efficiency and lifespan, and in addition, there is also demand for improvement in reducing the driving voltage.

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent document 1: WO2010 / 134350

[0009] Patent Document 2: WO2011 / 070963

[0010] Patent Document 3: WO2008 / 056746

[0011] Patent Document 4: WO2018 / 198844

[0012] Patent document 5: US10333077B2

[0013] Patent document 6: CN patent publication No. 111233847

[0014] Patent Document 7: KR Patent Publication No. 2019-0009211

[0015] Patent Document 8: KR Patent Publication No. 2019-0001357

[0016] Patent Document 9: WO2013 / 122402

[0017] Patent Document 10: KR Patent Publication No. 2021-0062771

[0018] Patent Document 3 discloses the use of an indolocarbazole compound as a host material for a light-emitting layer.

[0019] Patent Documents 4 and 5 disclose using an indolocarbazole compound and a biscarbazole compound as a mixed host material for a light-emitting layer.

[0020] Patent Documents 6, 7, and 8 disclose using an indolocarbazole compound substituted with a phenyldibenzofuranyl group as a host material for a light-emitting layer.

[0021] Patent Documents 9 and 10 disclose using an indolocarbazole compound substituted with a phenyldibenzofuranyl group and a biscarbazole compound as a mixed host material for a light-emitting layer.

[0022] However, none of them can be said to be sufficient, and further improvements are desired. Summary of the invention

[0023] Problems to be solved by the invention

[0024] Compared with liquid crystal displays, organic EL displays are thin and light, have high contrast, and can display high-speed animations. In addition, their design features such as curved and flexible surfaces are also highly valued, and they are widely used in display devices represented by mobile phones and televisions. However, in order to suppress battery consumption when used as portable terminals, further low voltage is required. In addition, as a light source, it is inferior to inorganic light-emitting diodes (LEDs) in terms of brightness or life, so it is required to improve efficiency or increase component life. In view of the above situation, the purpose of the present invention is to provide a practically useful organic EL element with low voltage, high efficiency, and long life characteristics.

[0025] Technical means of solving problems

[0026] The present inventors have conducted intensive studies and, as a result, have found that an organic electroluminescent device using a specific mixed host material in a light-emitting layer can solve the above-mentioned problems, thereby completing the present invention.

[0027] The present invention relates to an organic electric field light-emitting element, comprising one or more light-emitting layers between an anode and a cathode facing each other, wherein at least one light-emitting layer contains: a first host selected from a compound represented by the following general formula (1); a second host selected from a compound represented by the following general formula (2); and a light-emitting dopant material.

[0028] [Chemistry 1]

[0029]

[0030] In the general formula (1), ring G is an aromatic ring represented by formula (1a) and is condensed with two adjacent rings. Ring H is a heterocyclic ring represented by formula (1b) and is condensed with two adjacent rings at any position but not on the side including N.

[0031] X is independently N, CH, or CR, and at least one of them is N. Y is O or S.

[0032] Ar 1 It represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group in which two to five aromatic rings of an aromatic group selected from the above aromatic hydrocarbon groups and the above aromatic heterocyclic groups are linked.

[0033] Ar 2independently represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 17 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group in which two to five aromatic rings of an aromatic group selected from the above aromatic hydrocarbon groups and the above aromatic heterocyclic groups are linked.

[0034] Among them, Ar 1 and two Ar 2 At least one of them is a group represented by formula (1c). In addition, * represents a bonding position.

[0035] L 1 represents a single bond, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms,

[0036] R 1 Each independently represents deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking 2 to 5 aromatic rings of aromatic groups selected from the aromatic hydrocarbon groups and the aromatic heterocyclic groups. 1 When it is an aromatic hydrocarbon group, it can be 1 The bonded benzene rings are condensed to form a ring.

[0037] R 2 Each independently represents deuterium or an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a to f represent the number of substitutions, a and b each independently represent an integer of 0 to 4, c represents an integer of 0 to 2, d each independently represents an integer of 0 to 13, e represents an integer of 0 to 3, and f each independently represents an integer of 0 to 4. n represents the number of repetitions and represents an integer of 1 to 4.

[0038] [Chemistry 2]

[0039]

[0040] In formula (2), Ar 3 , and Ar 4 Each independently represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group in which two to five aromatic rings of these aromatic groups are linked.

[0041] L each independently represents a single bond, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms,

[0042] R 3 , R 6 , and R 7 Each independently represents deuterium or an aliphatic hydrocarbon group having 1 to 10 carbon atoms.

[0043] g to j and p to q represent the number of substitutions, g and h each independently represent an integer of 0 to 4, i and j each independently represent an integer of 0 to 3, and p and q each independently represent 0 to 12.

[0044] A preferred embodiment of the present invention is that in the general formula (1), all X are N, R 1 Deuterium, R 2 is deuterium, and Y is O.

[0045] In the general formula (1), there is Ar 2 At least one embodiment represented by any one of formula (3) to formula (5), more preferably the embodiment represented by formula (3).

[0046] [Chemistry 3]

[0047]

[0048] The compound represented by the general formula (1) may be in a form represented by any one of the following formulae (6) to (9).

[0049] [Chemistry 4]

[0050]

[0051] In the compound represented by the general formula (2), Ar 3 , and Ar 4 Each independently represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to three aromatic rings of these aromatic groups, and more preferably a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, or a substituted or unsubstituted terphenyl group. In the compound represented by the general formula (2), preferably R 3 A preferred embodiment of the present invention is that in the compound represented by the general formula (2), Ar 3 , and Ar 4 is a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, or a substituted or unsubstituted terphenyl group, or R 3 Any one of deuterium.

[0052] The compound of the general formula (2) may be in a form represented by the following formula (10).

[0053] [Chemistry 5]

[0054]

[0055] The organic electric field light-emitting element of the present invention is an organic electric field light-emitting element including the following light-emitting layer, that is, the light-emitting layer has a mixed host including two compounds and a dopant (luminescent dopant material). As the mixed host, the ratio of the compound represented by the general formula (1) to the total of the compound represented by the general formula (1) and the compound represented by the general formula (2) is preferably 10wt% or more and less than 80wt%, more preferably 20wt% or more and less than 70wt%. In addition, the more preferred luminescent dopant is an organic metal complex containing at least one metal selected from the group consisting of ruthenium, rhodium, palladium, silver, rhenium, osmium, iridium, platinum and gold, or a thermally activated delayed fluorescence luminescent dopant.

[0056] The present invention relates to a premixture comprising a first host and a second host, and is used to form a light-emitting layer in an organic electric field light-emitting element. The organic electric field light-emitting element includes the light-emitting layer containing the host and a light-emitting dopant material between an anode and a cathode facing each other. The premixture is characterized in that the first host is selected from the compound represented by the general formula (1), and the second host is selected from the compound represented by the general formula (2).

[0057] In addition, when manufacturing the organic electroluminescent element, it is preferred to include the following steps: after mixing the first host represented by the general formula (1) and the second host represented by the general formula (2) to prepare a premix, vapor depositing the host material containing the premix to form a light-emitting layer.

[0058] In the method for manufacturing the organic electroluminescent element, the difference between the 50% weight reduction temperatures of the first body and the second body is preferably within 20°C.

[0059] Effects of the Invention

[0060] According to the present invention, an organic EL element having low voltage, high efficiency and long life can be obtained by mixing a first host having a nitrogen-containing six-membered ring and a phenyldibenzofuranyl group or a phenyldibenzothiophene group in indolocarbazole and a biscarbazole compound as a second host. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] [ Figure 1 ] is a schematic cross-sectional view showing an example of an organic EL element. DETAILED DESCRIPTION

[0062] The organic electric field light-emitting element of the present invention is an organic electric field light-emitting element having multiple organic layers between an anode and a cathode, and is characterized in that the organic layer includes at least one light-emitting layer, and the light-emitting layer contains a first main body represented by the general formula (1), a second main body represented by the general formula (2), and a light-emitting dopant material.

[0063] In the general formula (1), ring G is an aromatic ring represented by formula (1a), which is condensed with two adjacent rings. In addition, ring H is a five-membered heterocyclic ring represented by formula (1b), which is condensed with two adjacent rings at any position, but not on the side including N. Therefore, the indolecarbazole ring has several isomeric structures, but their number is limited. According to the isomeric structure of the indolecarbazole ring, the compound represented by the general formula (1) is specifically represented by a structure such as formula (6) to formula (9), preferably formula (7) to formula (9), and more preferably a form represented by formula (9).

[0064] In general formula (1) and formula (6) to formula (9), common symbols have the same meanings. X is independently N, CH, or CR, and at least one is N. Preferably, at least two X are N, and more preferably, all X are N.

[0065] In formula (1c), and formula (3) to formula (5), common symbols have the same meanings. Formula (1c) can be represented by formula (3) to formula (5), preferably Ar 2 At least one of is represented by any one of formula (3) to formula (5), and is more preferably represented by formula (3).

[0066] Y is independently O or S, preferably O.

[0067] a to f represent the number of substitutions, a, b and f each independently represent an integer of 0 to 4, c represents an integer of 0 to 2, d each independently represent an integer of 0 to 13, and e represents an integer of 0 to 3. n represents the number of repetitions and is an integer of 1 to 4. Preferably, a and b each independently represent an integer of 1 to 4, c is an integer of 1 to 2, f each independently represent an integer of 0 or 4, and n is an integer of 1 or 2, and more preferably, a and b each independently represent an integer of 4, and c is an integer of 2.

[0068] Ar 1Each is independently a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking 2 to 5 aromatic rings of these aromatic groups, or a group represented by formula (1c). Preferably, it is a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking 2 to 5 aromatic hydrocarbon groups, or a group represented by formula (1c). More preferably, it is a substituted or unsubstituted phenyl group, or a substituted or unsubstituted linked aromatic group formed by linking 2 to 3 phenyl groups. The linking pattern of the phenyl groups is meta-linked or para-linked.

[0069] Ar 2 Each is independently a substituted or unsubstituted aromatic hydrocarbon group having 6 to 17 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group in which two to five aromatic rings of these aromatic groups are linked, or a group represented by formula (1c). Preferably, it is a substituted or unsubstituted aromatic hydrocarbon group having 6 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group in which two to five aromatic hydrocarbon groups are linked, or a group represented by formula (1c). More preferably, it is a substituted or unsubstituted phenyl group, or a substituted or unsubstituted linked aromatic group in which two to three phenyl groups are linked, or a group represented by formula (1c).

[0070] Ar 1 and two Ar 2 At least one of them is a group represented by formula (1c).

[0071] L 1 It is a single bond, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms. It is preferably a single bond or a substituted or unsubstituted phenylene group, and the connection pattern of the phenylene group may be either meta-linked or para-linked.

[0072] As the Ar 1 Specific examples of an unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, an unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a linked aromatic group in which two to five aromatic rings thereof are linked include: benzene, naphthalene, dihydroacenaphthene, acenaphthene, azulene, anthracene, Pyrene, phenanthrene, fluorene, triphenylene, pyridine, pyrimidine, triazine, thiophene, isothiazole, thiazole, pyridazine, pyrrole, pyrazole, imidazole, triazole, thiadiazole, pyrazine, furan, isoxazole, quinoline, isoquinoline, quinoxaline, quinazoline, thiadiazole, phthalazine, tetrazole, indole, benzofuran, benzothiophene, benzoxazole, benzothiazole, indazole, benzimidazole, benzotriazole, benzisothiazole, benzothiadiazole, purine, pyrone, coumarin, isocoumarin, chromone, dibenzofuran, dibenzothiophene, dibenzoselenophene, carbazole, or a group formed by removing one hydrogen from a compound composed of two to five of these linked together. Preferred examples include: benzene, naphthalene, dihydroacenaphthene, acenaphthene, azulene, anthracene, The terphenyl group may be pyrene, phenanthrene, fluorene, triphenylene, or a compound composed of 2 to 5 of these groups linked together. More preferably, it is phenyl, biphenyl, or terphenyl. The terphenyl group may be linked in a straight chain or may be branched.

[0073] As the Ar 2 Specific examples of the linked aromatic group which is an unsubstituted aromatic hydrocarbon group having 6 to 17 carbon atoms, an unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or two to five linked aromatic rings of these aromatic groups include benzene, naphthalene, acenaphthene, acenaphthene, azulene, anthracene, pyrene, phenanthrene, fluorene, pyridine, pyrimidine, triazine, thiophene, isothiazole, thiazole, pyridazine, pyrrole, pyrazole, imidazole, triazole, thiadiazole, pyrazine, furan, isoxazole , quinoline, isoquinoline, quinoxaline, quinazoline, thiadiazole, phthalazine, tetrazole, indole, benzofuran, benzothiophene, benzoxazole, benzothiazole, indazole, benzimidazole, benzotriazole, benzisothiazole, benzothiadiazole, purine, pyrone, coumarin, isocoumarin, chromone, dibenzofuran, dibenzothiophene, dibenzoselenophene, carbazole, or a group generated by taking out one hydrogen from a compound composed of 2 to 5 of these linked together. Preferred examples include: a group generated from a compound composed of benzene, naphthalene, dihydroacenaphthene, acenaphthene, azulene, anthracene, pyrene, phenanthrene, fluorene, or 2 to 5 of these linked together. More preferred are phenyl, biphenyl or terphenyl. The terphenyl may be linked in a straight chain or branched.

[0074] In L 1 In the case of an unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, the following groups are present in the same group as Ar 1 The same applies to the case of an unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms. Preferably, it is a substituted or unsubstituted phenylene group.

[0075] R 1Each independently represents deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking 2 to 5 aromatic rings of aromatic groups selected from the aromatic hydrocarbon group and the aromatic heterocyclic group. Deuterium or substituted or unsubstituted phenyl is preferred. Deuterium is more preferred. In addition, when R 1 When it is an aromatic hydrocarbon group, it can be 1 The bonded benzene rings are condensed to form a ring.

[0076] R 1 Specific examples of the unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, the unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or the unsubstituted linked aromatic group formed by linking 2 to 5 aromatic rings of these aromatic groups are the same as those described above for Ar 1 The same situation.

[0077] R 2 Each independently represents deuterium or an aliphatic hydrocarbon group having 1 to 10 carbon atoms, preferably deuterium.

[0078] Specific examples of the aliphatic hydrocarbon group having 1 to 10 carbon atoms include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, and decyl. An alkyl group having 1 to 4 carbon atoms is preferred.

[0079] In the general formula (2), the two carbazole rings may be bonded at the 2-position, 3-position, or 4-position, and are preferably bonded at the 3-position as shown in the formula (10). In the general formula (2) and the formula (10), the same symbols have the same meanings.

[0080] Ar 3 and Ar 4 Each independently represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking 2 to 5 aromatic rings of these aromatic groups. Preferably, it is a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a linked aromatic group formed by linking 2 to 3 aromatic rings of the aromatic hydrocarbon group, and more preferably, it is a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, or a substituted or unsubstituted terphenyl group. The terphenyl group may be linked in a straight chain or branched. In addition, as Ar 3 , and Ar 4Specific examples of the unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, the unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a linked aromatic group in which two to five aromatic rings thereof are linked are the same as those described above for Ar1.

[0081] L is independently a single bond, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms. It is preferably a single bond or a substituted or unsubstituted phenylene group. The connection pattern may be any one of ortho-, meta- or para-connection. In addition, as a specific example when L is an unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or an unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, it is the same as the case described in Ar1 except for the group generated by removing two hydrogen atoms.

[0082] R 3 , R 6 , and R 7 Each independently represents deuterium or an aliphatic hydrocarbon group having 1 to 10 carbon atoms. Deuterium is preferred. Specific examples of the aliphatic hydrocarbon group having 1 to 10 carbon atoms are the same as those described above for R2.

[0083] g to j and p to q represent the number of substitutions, g and h each independently represent an integer of 0 to 4, i and j each independently represent an integer of 0 to 3, and p and q each independently represent an integer of 0 to 12. Preferably, g and h each independently represent an integer of 1 to 4, i and j each independently represent an integer of 1 to 3, and p and q each independently represent an integer of 1 to 12, and more preferably, g and h each independently represent an integer of 4, and i and j each independently represent an integer of 3.

[0084] In this specification, a linked aromatic group refers to an aromatic group formed by linking two or more aromatic rings of an aromatic group using a single bond. These linked aromatic groups may be straight-chain or branched. The linking position when the benzene rings are linked to each other may be any one of the ortho position, meta position, or para position, but preferably the para position or meta position is linked. The aromatic group may be an aromatic hydrocarbon group or an aromatic heterocyclic group, and a plurality of aromatic groups may be the same or different.

[0085] In the present specification, the aromatic hydrocarbon group, the aromatic heterocyclic group, or the linked aromatic group may have a substituent. When having a substituent, the substituent is preferably deuterium, halogen, cyano, triarylsilyl, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or a diarylamino group having 12 to 44 carbon atoms. Here, when the substituent is an aliphatic hydrocarbon group having 1 to 10 carbon atoms, it may be straight-chain, branched, or cyclic. In addition, when the triarylsilyl group or the diarylamino group replaces the aromatic hydrocarbon group, the aromatic heterocyclic group, or the linked aromatic group, silicon and carbon, or nitrogen and carbon are bonded to a single bond, respectively.

[0086] In addition, the number of the substituents is preferably 0 to 5, preferably 0 to 2. In addition, when calculating the carbon number of an aromatic hydrocarbon group or an aromatic heterocyclic group having a substituent, the carbon number of the substituent is not included. However, it is preferred that the total carbon number including the carbon number of the substituent satisfies the above range.

[0087] Specific examples of the substituent include deuterium, cyano, methyl, ethyl, propyl, isopropyl, butyl, tert-butyl, pentyl, neopentyl, cyclopentyl, hexyl, cyclohexyl, heptyl, octyl, nonyl, decyl, vinyl, propenyl, butenyl, pentenyl, methoxy, ethoxy, propoxy, butoxy, pentyloxy, diphenylamino, naphthylphenylamino, dinaphthylamino, dianthrylamino, diphenanthrylamino, dipyrenylamino, etc. Preferably, deuterium, cyano, methyl, ethyl, tert-butyl, propyl, butyl, pentyl, neopentyl, hexyl, heptyl, or octyldiphenylamino, naphthylphenylamino, or dinaphthylamino.

[0088] In addition, part or all of the hydrogen atoms in the unsubstituted aromatic hydrocarbon group, the unsubstituted aromatic heterocyclic group, the unsubstituted linked aromatic group, the substituents of these aromatic groups, or the aliphatic hydrocarbon group may be deuterated. That is, part or all of the hydrogen atoms in the compounds represented by general formulae (1) to (2) and formulae (6) to (10) may be deuterated. In addition, deuterated compounds include both the case where a single compound is included and the case where a mixture of two or more compounds is included. That is, if the deuteration rate is specifically described, when the deuteration rate is 50%, it means that on average half of the hydrogen atoms in all the hydrogen atoms are replaced by deuterium. The deuterated compound may be a single compound or a mixture of compounds having different deuteration rates.

[0089] When part of the hydrogen atoms in the compounds represented by general formulae (1) to (2) and (6) to (10) are deuterated, it is preferred that 20% or more of the hydrogen atoms are deuterated, more preferably 40% or more, and even more preferably 50% or more.

[0090] The deuteration rate can be obtained by mass spectrometry or proton nuclear magnetic resonance spectroscopy. For example, in the case of obtaining by proton nuclear magnetic resonance spectroscopy, first, the compound and the internal standard substance are added to the deuterated solvent and dissolved to prepare the measurement sample, and the proton concentration [mol / g] of the compound contained in the measurement sample is calculated based on the integrated intensity ratio of the internal standard substance and the compound source. Next, the ratio of the proton concentration of the deuterated compound to the proton concentration of the corresponding non-deuterated compound is calculated and subtracted from 1, thereby calculating the deuteration rate of the deuterated compound. In addition, the deuteration rate of the partial structure can be calculated according to the integrated intensity of the chemical shift derived from the partial structure as the object, according to the same process as above.

[0091] Specific examples of the compound represented by the general formula (1) are shown below, but the compound is not limited to these exemplified compounds.

[0092] [Chemistry 6]

[0093]

[0094] [Chemistry 7]

[0095]

[0096] [Chemistry 8]

[0097]

[0098] [Chemistry 9-1]

[0099]

[0100] [Chemistry 9-2]

[0101]

[0102] [Chemistry 9-3]

[0103]

[0104] Specific examples of the compound represented by the general formula (2) are shown below, but the compound is not limited to these exemplified compounds.

[0105] [Chemistry 10]

[0106]

[0107] [Chemistry 11]

[0108]

[0109] [Chemistry 12]

[0110]

[0111] [Chemistry 13]

[0112]

[0113] [Chemistry 14]

[0114]

[0115] [Chemistry 15-1]

[0116]

[0117] [Chemistry 15-2]

[0118]

[0119] The host material for an organic EL device of the present invention is suitably used as a host material for a light-emitting layer.

[0120] Next, the structure of the organic EL element of the present invention will be described with reference to the drawings, but the structure of the organic EL element of the present invention is not limited thereto.

[0121] Figure 1 It is a cross-sectional view showing a structural example of a general organic EL element used in the present invention, 1 represents a substrate, 2 represents an anode, 3 represents a hole injection layer, 4 represents a hole transport layer, 5 represents a light-emitting layer, 6 represents an electron transport layer, and 7 represents a cathode. In the organic EL element of the present invention, an exciton blocking layer may be adjacent to the light-emitting layer, and an electron blocking layer may also be provided between the light-emitting layer and the hole injection layer. The exciton blocking layer may be inserted into either the anode side or the cathode side of the light-emitting layer, and may also be inserted into both sides at the same time. In the organic EL element of the present invention, an anode, a light-emitting layer, and a cathode are provided as necessary layers, but in addition to the necessary layers, a hole injection transport layer and an electron injection transport layer may also be provided, and a hole blocking layer may also be provided between the light-emitting layer and the electron injection transport layer. In addition, a hole injection transport layer refers to either or both of a hole injection layer and a hole transport layer, and an electron injection transport layer refers to either or both of an electron injection layer and an electron transport layer.

[0122] It can also be used with Figure 1 In the opposite structure, that is, the cathode 7, the electron transport layer 6, the light emitting layer 5, the hole transport layer 4, the hole injection layer 3, and the anode 2 are sequentially stacked on the substrate 1, in which case the layers can be added or omitted as needed.

[0123] -Substrate-

[0124] The organic EL element of the present invention is preferably supported on a substrate. The substrate is not particularly limited as long as it is a substrate conventionally used for organic EL elements, and for example, a substrate made of glass, transparent plastic, quartz, etc. can be used.

[0125] -anode-

[0126] As the anode material in the organic EL element, a material containing a metal, alloy, electrically conductive compound or a mixture thereof with a large work function (4 eV or more) can be preferably used. Specific examples of such electrode materials include: metals such as Au; CuI, indium tin oxide (ITO), SnO 2 , ZnO and other conductive transparent materials. In addition, IDIXO (In 2 O 3 -ZnO) and other amorphous materials that can be made into transparent conductive films. The anode can be formed into a thin film by evaporation or sputtering, and a pattern of the desired shape can be formed by photolithography. Or, when the pattern accuracy is not very necessary (about 100μm or more), a mask of the desired shape can be used to form a pattern when the electrode material is evaporated or sputtered. Alternatively, when a coatable substance such as an organic conductive compound is used, a wet film forming method such as printing or coating can be used. When light is taken out from the anode, it is ideal to make the transmittance greater than 10%. In addition, the sheet resistance of the anode is preferably less than several hundred Ω / Υ. The film thickness also depends on the material, and is usually selected in the range of 10nm to 1000nm, preferably 10nm to 200nm.

[0127] -cathode-

[0128] On the other hand, as the cathode material, a material containing a metal (electron injecting metal) with a small work function (less than 4 eV), an alloy, an electrically conductive compound, or a mixture thereof can be used. Specific examples of such electrode materials include sodium, sodium-potassium alloy, magnesium, lithium, a magnesium / copper mixture, a magnesium / silver mixture, a magnesium / aluminum mixture, a magnesium / indium mixture, an aluminum / aluminum oxide (Al2O3), and a magnesium / silver mixture. 2 O 3) mixture, indium, lithium / aluminum mixture, rare earth metals, etc. Among these, in terms of electron injectability and durability to oxidation, etc., a mixture of an electron injectable metal and a second metal whose work function value is larger than that of the metal and stable is suitable, such as a magnesium / silver mixture, a magnesium / aluminum mixture, a magnesium / indium mixture, an aluminum / aluminum oxide mixture, a lithium / aluminum mixture, aluminum, etc. The cathode can be made as follows: these cathode materials are formed into a thin film by methods such as evaporation or sputtering. In addition, as a cathode, the sheet resistance is preferably less than hundreds of Ω / Y, and the film thickness is usually selected in the range of 10nm to 5μm, preferably 50nm to 200nm. In addition, in order to make the emitted light transparent, if either the anode or cathode of the organic EL element is transparent or translucent, the luminous brightness is improved, which is suitable.

[0129] In addition, after the metal is formed on the cathode with a film thickness of 1nm to 20nm, the conductive transparent material listed in the description of the anode is formed thereon, thereby making a transparent or translucent cathode. By applying the method, an element in which both the anode and the cathode are transparent can be made.

[0130] -Luminous layer-

[0131] The light-emitting layer is a layer that emits light after excitons are generated by recombination of holes and electrons injected from the anode and the cathode, respectively, and the light-emitting layer may contain an organic light-emitting dopant material and a host material.

[0132] The host material (also referred to as the host material of the present invention) represented by any one of the general formula (1) and general formula (6) to general formula (9) is used in the host. The host material of the present invention can be one, or two or more different compounds can be used, or other host materials such as one or more types of known host materials can be used in combination. As other host materials, it is preferred that the compound has hole transport ability, electron transport ability, prevents the long wavelength of luminescence, and has a high glass transition temperature.

[0133] When the host material of the present invention is included as the first host material, it is particularly preferred to use a compound represented by any one of the general formula (2) and the general formula (10) as the second host material, but other host materials shown below may also be used as the second host. In addition, when the host material of the present invention is used as the first host material and the compound represented by any one of the general formula (2) and the general formula (10) is used as the second host material, other host materials may be used as the third host material.

[0134] Other host materials are known in a number of patent documents and the like, and can be selected from these. Specific examples of the host material are not particularly limited, and examples thereof include indolecarbazole derivatives described in WO2008 / 056746A1 or WO2008 / 146839A1, carbazole derivatives described in WO2009 / 086028A1 or WO2012 / 077520A1, CBP (N,N-biscarbazolylbiphenyl) derivatives, triazine derivatives described in WO2014 / 185595A1 or WO2018 / 021663A1, indenocarbazole derivatives described in WO2010 / 136109A1 or WO2011 / 000455A1, dibenzofuran derivatives described in WO2015 / 169412A1, triazole derivatives, indole derivatives, oxazole derivatives, oxadiazole derivatives, imidazole derivatives, and polyarylalkane derivatives. , pyrazoline derivatives, pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, distyrene derivatives, silazane derivatives, aromatic tertiary amine compounds, styrylamine compounds, aromatic dimethylene compounds, porphyrin compounds, anthraquinone dimethane derivatives, anthrone derivatives, diphenylquinone derivatives, dioxythiopyran derivatives, naphthylperylene and other heterocyclic tetracarboxylic anhydrides, phthalocyanine derivatives, metal complexes of 8-hydroxyquinoline derivatives or metal phthalocyanines, various metal complexes represented by metal complexes of benzoxazole or benzothiazole derivatives, polysilane compounds, poly(N-vinylcarbazole) derivatives, aniline copolymers, thiophene oligomers, polythiophene derivatives, polyphenylene derivatives, polyparaphenylenevinylene derivatives, polyfluorene derivatives and other polymer compounds, etc.

[0135] Specific examples of the other host materials are shown below, but the present invention is not limited to these.

[0136] [Chemistry 16]

[0137]

[0138] Preferred examples of the organic light-emitting dopant material include phosphorescent dopants, fluorescent dopants, and thermally activated delayed fluorescent dopants.

[0139] As a phosphorescent dopant, an organic metal complex comprising at least one metal selected from ruthenium, rhodium, palladium, silver, rhenium, osmium, iridium, platinum and gold may be contained. Specifically, iridium complexes described in "Journal of the American Chemical Society (J.Am.Chem.Soc.)" 2001,123,4304, JP2013-530515A, US2016 / 0049599A1, US2017 / 0069848A1, US2018 / 0282356A1, or US2019 / 0036043A1, or platinum complexes described in US2018 / 0013078A1, or KR2018 / 094482A, etc. may be suitably used, but are not limited to these.

[0140] The phosphorescent dopant material may be contained in the light emitting layer in one kind or in two or more kinds. The content of the phosphorescent dopant material is preferably 0.1 wt% to 30 wt%, more preferably 1 wt% to 20 wt%, based on the host material.

[0141] The phosphorescent dopant material is not particularly limited, and specific examples include the following.

[0142] [Chemistry 17]

[0143]

[0144] [Chemistry 18-1]

[0145]

[0146] [Chemistry 18-2]

[0147]

[0148] The fluorescent dopant is not particularly limited, and examples thereof include benzoxazole derivatives, benzothiazole derivatives, benzimidazole derivatives, styrylbenzene derivatives, polyphenyl derivatives, diphenylbutadiene derivatives, tetraphenylbutadiene derivatives, naphthalimide derivatives, coumarin derivatives, condensed aromatic compounds, perinone derivatives, oxadiazole derivatives, oxazine derivatives, aldazine derivatives, pyrrolidine derivatives, cyclopentadiene derivatives, distyrylanthracene derivatives, quinacridone derivatives, pyrrolopyridine derivatives, thiadiazolopyridine derivatives, styrylamine derivatives, diketopyrrolopyrrole derivatives, aromatic dimethyl compounds, metal complexes of 8-hydroxyquinoline derivatives or metal complexes of pyrromethene derivatives, rare earth complexes, various metal complexes represented by transition metal complexes, polymer compounds such as polythiophene, polyphenylene, and polyphenylene vinylene, and organosilane derivatives. Preferred examples include condensed aromatic derivatives, styryl derivatives, diketopyrrolopyrrole derivatives, oxazine derivatives, pyrromethene metal complexes, transition metal complexes, or lanthanide complexes, and more preferred examples include naphthalene, pyrene, Triphenylene, benzo[c]phenanthrene, benzo[a]anthracene, pentacene, perylene, fluoranthene, acenaphthofluoranthene, dibenzo[a,j]anthracene, dibenzo[a,h]anthracene, benzo[a]naphthalene, hexacene, naphtho[2,1-f]isoquinoline, α-naphthaphenanthridine, phenanthrooxazole, quinolino[6,5-f]quinoline, benzonaphtho[2,3-b]thiophene, etc. These may have an alkyl group, an aryl group, an aromatic heterocyclic group, or a diarylamino group as a substituent.

[0149] The light-emitting layer may contain only one type of fluorescent dopant material or two or more types of fluorescent dopant materials. The content of the fluorescent dopant material is preferably 0.1 wt% to 20 wt%, more preferably 1 wt% to 10 wt%, based on the host material.

[0150] The thermally activated delayed fluorescence dopant is not particularly limited, and examples thereof include metal complexes such as tin complexes or copper complexes, or indolecarbazole derivatives described in WO2011 / 070963A1, cyanobenzene derivatives and carbazole derivatives described in Nature 2012, 492, 234, phenazine derivatives, oxadiazole derivatives, triazole derivatives, sulfone derivatives, phenoxazine derivatives, and acridine derivatives described in Nature Photonics 2014, 8, 326.

[0151] The thermally activated delayed fluorescence dopant material is not particularly limited, and specific examples thereof include the following.

[0152] [Chemistry 19]

[0153]

[0154] The thermally activated delayed fluorescent dopant material may contain only one or more than one in the light-emitting layer. In addition, the thermally activated delayed fluorescent dopant may be mixed with a phosphorescent dopant or a fluorescent dopant. The content of the thermally activated delayed fluorescent dopant material is preferably 0.1wt% to 50wt%, more preferably 1wt% to 30wt% relative to the host material.

[0155] -Injection layer-

[0156] The so-called injection layer is a layer provided between the electrode and the organic layer in order to reduce the driving voltage or increase the luminous brightness. There are hole injection layer and electron injection layer, which can exist between the anode and the light-emitting layer or the hole transport layer, and between the cathode and the light-emitting layer or the electron transport layer. The injection layer can be provided as needed.

[0157] -Hole blocking layer-

[0158] The so-called hole blocking layer, in a broad sense, has the function of an electron transport layer and includes a hole blocking material that has the function of transporting electrons but has a significantly lower ability to transport holes. It can increase the probability of recombination between electrons and holes in the light-emitting layer by transporting electrons and blocking holes.

[0159] -Electron blocking layer-

[0160] The electron blocking layer, in a broad sense, has the function of a hole transporting layer, and can increase the probability of recombination between electrons and holes in the light-emitting layer by transporting holes and blocking electrons.

[0161] As the material of the electron blocking layer, a known electron blocking layer material can be used, and the material of the hole transport layer described later can be used as necessary. The film thickness of the electron blocking layer is preferably 3 nm to 100 nm, more preferably 5 nm to 30 nm.

[0162] - Exciton blocking layer -

[0163] The so-called exciton blocking layer is a layer used to block the excitons generated by the recombination of holes and electrons in the light-emitting layer from diffusing to the charge transport layer. By inserting this layer, the excitons can be efficiently sealed in the light-emitting layer, which can improve the luminous efficiency of the element. In an element with two or more light-emitting layers adjacent to each other, the exciton blocking layer can be inserted between two adjacent light-emitting layers.

[0164] As the material of the exciton-blocking layer, a known exciton-blocking layer material can be used, for example, 1,3-dicarbazolylbenzene (mCP) or bis(2-methyl-8-hydroxyquinoline)-4-phenylphenol aluminum (III) (BAlq) can be mentioned.

[0165] -Hole transport layer-

[0166] The hole transport layer includes a hole transport material having the function of transporting holes, and the hole transport layer may be provided as a single layer or multiple layers.

[0167] As a hole transport material, it is a material having any of the properties of hole injection or transport and electron barrier, and can be any of organic and inorganic substances. In the hole transport layer, any one can be selected from previously known compounds and used. As the hole transport material, for example, porphyrin derivatives, arylamine derivatives, triazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives and pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, oxazole derivatives, styryl anthracene derivatives, fluorenone derivatives, hydrazone derivatives, distyrene derivatives, silazane derivatives, aniline copolymers, and conductive polymer oligomers, especially thiophene oligomers, etc., preferably using porphyrin derivatives, arylamine derivatives and styrylamine derivatives, more preferably using arylamine derivatives.

[0168] -Electron transport layer-

[0169] The electron transport layer includes a material having a function of transporting electrons, and the electron transport layer may be provided as a single layer or multiple layers.

[0170] As an electron transport material (sometimes also serving as a hole blocking material), it is sufficient as long as it has the function of transmitting the electrons injected from the cathode to the light-emitting layer. The electron transport layer can be selected from any of the previously known compounds, for example, polycyclic aromatic derivatives such as naphthalene, anthracene, and phenanthroline, tris(8-hydroxyquinoline)aluminum(III) derivatives, phosphine oxide derivatives, nitro-substituted fluorene derivatives, diphenylquinone derivatives, dioxide thiopyran derivatives, carbodiimide, fluorenyl methane derivatives, anthraquinone dimethane derivatives and anthrone derivatives, bipyridine derivatives, quinoline derivatives, oxadiazole derivatives, benzimidazole derivatives, benzothiazole derivatives, indole and carbazole derivatives, etc., and further, polymer materials that introduce these materials into polymer chains or use these materials as the main chain of polymers can also be used.

[0171] The method for manufacturing an organic electroluminescent element of the present invention comprises: a step of premixing the first host material and the second host material, and a step of forming a light-emitting layer by vapor deposition of the obtained mixture from a vapor deposition source. By premixing the two host materials in this way, the performance of the organic EL element can be improved. As a mixing method, powder mixing or melt mixing can be used.

[0172] The composition obtained by the premixing is preferably such that the difference in 50% weight loss temperature between the first host material and the second host material is within 20°C. Here, the 50% weight loss temperature refers to the temperature at which the weight is reduced by 50% when the temperature is increased from room temperature to 550°C at a rate of 10°C per minute in a nitrogen flow reduced pressure (1 Pa) thermogravimetry-differential thermal analysis (TG-DTA) measurement. It is believed that gasification caused by evaporation or sublimation is most intense near the temperature.

[0173] Example

[0174] Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples and can be implemented in various forms without departing from the gist of the present invention.

[0175] As representative examples, the synthesis examples of compound 1-1, compound 1-3, compound 1-8, compound 1-13, compound 1-29, compound 1-44, compound 1-55 and compound 1-57 are shown. Other compounds were synthesized using similar methods. In addition, the deuteration rate was determined by proton nuclear magnetic resonance spectroscopy.

[0176] Synthesis example 1

[0177] [Chemistry 20]

[0178]

[0179] To 7.0 g (13.4 mmol) of compound (a), 5.0 g (13.5 mmol) of compound (b), 0.12 g (0.21 mmol) of CX21, 3.2 g (30.2 mmol) of sodium carbonate, 250 mL of toluene, 100 mL of ethanol, and 20 mL of water were added, and the mixture was stirred at 75° C. for 2 hours under a nitrogen atmosphere. After cooling to room temperature, 50 mL of water was added, and the organic phase was extracted with toluene, and MgSO 4 The organic phase was dried and concentrated to dryness, thereby obtaining 10.7 g of a yellow solid. The obtained solid was purified by silica gel column chromatography and crystallization to obtain 3.5 g (4.80 mmol, yield 36%) of compound (1-1) as a yellow solid (APCI-TOFMS (Atmospheric pressure chemical ionization-time-of-flight mass spectrometer), m / z 730 [M+H] + ).

[0180] Synthesis example 2

[0181] [Chemistry 21]

[0182]

[0183] To 5.9 g (9.86 mmol) of compound (c), 3.6 g (9.72 mmol) of compound (b), 2.3 g (21.7 mmol) of sodium carbonate, 80 mg (0.14 mmol) of CX21, 80 g of m-xylene, 40 g of ethanol, and 8.0 g of water were added, and the mixture was stirred at 110° C. for 2.5 hours under a nitrogen atmosphere. After cooling to room temperature, 50 mL of water was added, and the organic phase was extracted with toluene, and MgSO 4 The product was dried and concentrated to dryness to obtain 7.7 g of a yellow solid. The product was purified by silica gel column chromatography to obtain 5.4 g (6.70 mmol, yield 68%) of compound (1-3) as a yellow solid (APCI-TOFMS, m / z 806 [M+H] + ).

[0184] Synthesis example 3

[0185] [Chemistry 22]

[0186]

[0187] To 39.0 g (75 mmol) of compound (a), 15 g (75 mmol) of compound (e), 4.3 g (3.75 mmol) of tetrakis-triphenylphosphine palladium (0), 48.8 g (150 mmol) of cesium carbonate, and 500 mL of 1,4-dioxane were added, and stirred at 110° C. for 4 hours under a nitrogen atmosphere. After cooling to room temperature, the reaction solution was added to 1 L of water, and the obtained yellow solid was purified by silica gel column chromatography to obtain 15.2 g (24 mmol, yield 32%) of intermediate (f) as a yellow solid. Next, 2.5 g (6.75 mmol) of compound (b), 57.9 mg (0.10 mmol) of Cx21, 1.8 g (13.5 mmol) of potassium carbonate, 18.7 g of water, and 145 g of m-xylene were added to 4.3 g (6.75 mmol) of the obtained intermediate (f), and stirred at 110° C. overnight under a nitrogen atmosphere. After cooling to room temperature, 50 mL of water was added, and the organic phase was extracted with toluene, and MgSO 4The mixture was dried and concentrated to dryness to obtain 2.7 g of a yellow solid. The mixture was purified by silica gel column chromatography to obtain 1.2 g (1.49 mmol, yield 22%) of compound (1-13) as a yellow solid (APCI-TOFMS, m / z 806 [M+H] + ).

[0188] Synthesis example 4

[0189] [Chemistry 23]

[0190]

[0191] To 10.0 g (29.6 mmol) of compound (g) was added 100 mL of deuterated benzene (C 6 D 6 ), 30.0 g (200 mmol) of trifluoromethanesulfonic acid (TfOH), heated and stirred at 50° C. for 3 hours under a nitrogen atmosphere. The reaction solution was added to a deuterated aqueous solution (200 mL) of sodium carbonate (23.0 g) for quenching, and separated and purified to obtain 8.7 g (25.0 mmol, yield 84%, deuteration rate 93%) of compound (h) as a deuterated product.

[0192] Synthesis example 5

[0193] [Chemistry 24]

[0194]

[0195] Under a nitrogen atmosphere, add 0.8 g of 60 wt% sodium hydride to 100 mL of N,N'-dimethylacetamide to prepare a suspension. Add 5.0 g (14.4 mmol) of the intermediate (h) dissolved in 160 mL of N,N'-dimethylacetamide and stir for 30 minutes. Add 4.1 g (18.1 mmol) of compound (i) and stir for 1 hour. Add the reaction solution to a mixed solution of distilled water (500 mL) while stirring, and filter out the precipitated solid. The obtained solid is refined and crystallized by silica gel column chromatography to obtain 3.9 g (7.26 mmol, yield 50%) of compound (j) as a yellow solid.

[0196] Next, 1.5 g (4.09 mmol) of compound (b), 31.9 mg (0.056 mmol) of Cx21, 1.0 g (7.44 mmol) of potassium carbonate, 10.3 g of water, and 80.0 g of m-xylene were added to 2.0 g (3.72 mmol) of the obtained intermediate (j), and stirred at 110° C. overnight under a nitrogen atmosphere. After cooling to room temperature, 50 mL of water was added, and the organic phase was extracted with toluene, and MgSO 4 The mixture was dried and concentrated to dryness to obtain 3.1 g of a yellow solid. The mixture was purified by silica gel column chromatography to obtain 1.6 g (2.15 mmol, yield 58%, deuteration rate 43%) of compound (1-29) as a yellow solid (APCI-TOFMS, m / z 745 [M+H] + ).

[0197] Synthesis example 6

[0198] [Chemistry 25]

[0199]

[0200] To 2.8 g (5.36 mmol) of compound (a), 2.0 g (5.40 mmol) of compound (k), 50 mg (0.087 mmol) of CX21, 1.3 g (12.3 mmol) of sodium carbonate, 100 mL of toluene, 40 mL of ethanol, and 10 mL of water were added, and the mixture was stirred at 75° C. for 2 hours under a nitrogen atmosphere. After cooling to room temperature, 20 mL of water was added, and the organic phase was extracted with toluene, and MgSO 4 The organic phase was dried and concentrated to dryness to obtain 3.4 g of a yellow solid. The obtained solid was purified by silica gel column chromatography and crystallization to obtain 1.0 g (1.37 mmol, yield 26%) of compound (1-55) as a yellow solid (APCI-TOFMS, m / z 730 [M+H] + ).

[0201] Synthesis Example 7

[0202] [Chemistry 26]

[0203]

[0204] To 4.3 g (16.9 mmol) of compound (n), 6.0 g (18.6 mmol) of compound (o), 0.32 g (1.68 mmol) of copper (I) iodide, 0.49 g (3.38 mmol) of 8-hydroxyquinoline, 4.7 g (34.0 mmol) of potassium carbonate, and 300 mL of 1,3-dimethyl-2-imidazolidinone were added, and the mixture was stirred overnight at 140°C under a nitrogen atmosphere. After cooling to room temperature, the reaction solution was added to a mixed solution of distilled water (500 mL) while stirring, and the precipitated solid obtained was filtered out. The obtained solid was purified by silica gel column chromatography and crystallized to obtain 3.38 g (6.78 mmol, yield 40%) of intermediate (p) as a white solid.

[0205] Next, under a nitrogen atmosphere, 0.24 g of 60 wt% sodium hydride was added to 40 mL of N,N'-dimethylacetamide to prepare a suspension. 2.0 g (4.01 mmol) of the intermediate (p) dissolved in 100 mL of N,N'-dimethylacetamide was added thereto, and the mixture was stirred for 30 minutes. After 1.7 g (4.81 mmol) of compound (q) was added thereto, the mixture was stirred for 1 hour. The reaction solution was added to a mixed solution of methanol (100 mL) and distilled water (25 mL) while stirring, and the precipitated solid obtained was filtered out. The obtained solid was refined and crystallized by silica gel column chromatography to obtain 0.97 g (1.20 mmol, yield 30%) of compound 1-57 as a yellow solid (APCI-TOFMS, m / z 806 [M+H] + ).

[0206] Synthesis example 8

[0207] [Chemistry 27]

[0208]

[0209] To 12.0 g (23.0 mmol) of compound (a), 7.9 g (27.4 mmol) of compound (r), 0.20 g (0.34 mmol) of CX21, 5.5 g (51.7 mmol) of sodium carbonate, 500 g of toluene, 300 g of ethanol, and 50 g of water were added, and the mixture was stirred at 75°C for 16 hours under a nitrogen atmosphere. After cooling to room temperature, 100 mL of water was added, and the organic phase was extracted with toluene, and MgSO 4The organic phase was dried and concentrated to dryness to obtain 17.0 g of a light yellow solid. The obtained solid was purified by silica gel column chromatography and crystallization to obtain 7.1 g (9.74 mmol, yield 42%) of compound (1-44) as a yellow solid (APCI-TOFMS, m / z 730 [M+H] + ).

[0210] Synthesis example 9

[0211] [Chemistry 28]

[0212]

[0213] Under a nitrogen atmosphere, 1.1 g of 60 wt% sodium hydride was added to 30 ml of N,N'-dimethylacetamide to prepare a suspension. 9.9 g (19.9 mmol) of the intermediate (p) dissolved in 170 mL of N,N'-dimethylacetamide was added thereto and stirred for 30 minutes. 6.4 g (23.9 mmol) of compound (s) was added thereto and stirred for 1 hour. The reaction solution was added to a mixed solution of methanol (500 mL) and distilled water (500 mL) while stirring, and the precipitated solid obtained was filtered out. 13.6 g of the obtained solid was purified and crystallized by silica gel column chromatography to obtain 11.3 g (15.5 mmol, yield 78%) of compound 1-8 (APCI-TOFMS, m / z 730 [M+H]+) as a yellow solid.

[0214] Synthesis example 10

[0215] [Chemistry 29]

[0216]

[0217] To 3.0 g (7.10 mmol) of compound (t) were added 2.0 g (8.58 mmol) of compound (u), 100 mL of m-xylene, 0.2 g (0.39 mmol) of bis(tri-tert-butylphosphine)palladium, and 4.9 g (35.5 mmol) of potassium carbonate, and the mixture was stirred for 5 hours under heating reflux in a nitrogen atmosphere. After the reaction solution was cooled, it was separated and purified to obtain 1.5 g (2.61 mmol, yield 37%, deuteration rate 46%) of compound (2-109) as a white solid. (APCI-TOFMS, m / z 575 [M+H]+).

[0218] Synthesis example 11

[0219] [Chemistry 30]

[0220]

[0221] To 8.3 g (14.8 mmol) of compound (2-2) was added 160 mL of deuterated benzene (C 6 D 6 ), 10.0 g of deuterated trifluoromethanesulfonic acid-d (TfOD), heated and stirred at 50°C under a nitrogen atmosphere for 6.5 hours. The reaction solution was added to a deuterated aqueous solution (200 mL) of sodium carbonate (7.4 g) for quenching, and separated and purified to obtain 2.5 g (4.25 mmol, yield 29%, deuteration rate 79%) of white solid compound (2-116) (APCI-TOFMS, m / z 589 [M+H] +).

[0222] Compound 1-32, which is a deuterated product, was synthesized by reacting in the same manner as in Synthesis Example 4. The deuteration rate was calculated in the same manner as in Compound 1-29 and was found to be 90% for Compound 1-32.

[0223] Compound 2-118, which is a deuterated product, was synthesized by reacting in the same manner as in Synthesis Example 11. The deuteration rate was calculated in the same manner as in Compound 2-109 and Compound 2-116 and was found to be 71% for Compound 2-118.

[0224] The compounds used in Examples and Comparative Examples are shown below.

[0225] [Chemistry 31]

[0226]

[0227] Example 1

[0228] On a glass substrate on which an anode made of ITO with a film thickness of 110 nm was formed, a vacuum deposition method was used at a vacuum degree of 4.0×10 -5 Pa is used to stack each thin film. First, HAT-CN is formed into a 25nm thickness on ITO as a hole injection layer, and then Spiro (spiro)-TPD is formed into a 30nm thickness as a hole transport layer. Next, HT-1 is formed into a 10nm thickness as an electron blocking layer. Next, compound 1-1 as the first main body, compound 2-2 as the second main body, and Ir (ppy) as a light-emitting dopant are co-deposited from different evaporation sources. 3 , forming a light-emitting layer with a thickness of 40nm. At this time, in Ir(ppy) 3Co-evaporation was performed under the evaporation conditions in which the concentration of ET-1 became 10wt%. Next, ET-1 was formed into a thickness of 20nm as an electron transport layer. Furthermore, LiF was formed into a thickness of 1nm as an electron injection layer on the electron transport layer. Finally, Al was formed into a thickness of 70nm as a cathode on the electron injection layer to produce an organic EL element.

[0229] Embodiments 2 to 21

[0230] An organic EL device was produced in the same manner as in Example 1 except that the compounds shown in Table 1 were used as the first host and the second host and the weight ratios shown in Table 1 were used.

[0231] Examples 22 to 26

[0232] An organic EL element was produced in the same manner as in Example 1 except that the first main body and the second main body shown in Table 1 were weighed in a weight ratio shown in Table 1 and ground and mixed in a mortar to obtain a premix, and the premix was vapor-deposited from a vapor deposition source.

[0233] Comparative Examples 1 to 6

[0234] An organic EL device was produced in the same manner as in Example 1 except that the compounds shown in Table 1 were used as the first host and the second host and the weight ratios shown in Table 1 were used.

[0235] Comparative Examples 7 to 12

[0236] An organic EL element was produced in the same manner as in Example 1 except that the first main body and the second main body shown in Table 1 were weighed in a weight ratio shown in Table 1 and ground and mixed in a mortar to obtain a premix, and the premix was vapor-deposited from a vapor deposition source.

[0237] The evaluation results of the produced organic EL elements are shown in Table 1. In the table, the luminance, voltage, and power efficiency are given by the drive current of 10 mA / cm 2 The value at the time of LT97 is the initial characteristic. 2 The time it takes for the brightness to decay to 97% when the initial brightness is 100%, and the lifetime characteristics are shown. The numbers of the host compound, the first host, and the second host are the numbers added to the exemplary compounds, and the weight ratio is first host:second host.

[0238] [Table 1]

[0239]

[0240] From the results in Table 1, it can be seen that Examples 1 to 26 have improved power efficiency and lifespan compared to Comparative Examples, showing good characteristics.

[0241] Table 2 shows the 50% weight loss temperatures (T 50 ).

[0242] [Table 2]

[0243] Compound <![CDATA[T 50 [℃]]]> 1-1 289 2-2 266 2-42 292 2-43 296 2-118 296 A 269 D 262

[0244] Industrial Applicability

[0245] According to the present invention, an organic EL element having low voltage, high efficiency and long life can be obtained by mixing a first host having a nitrogen-containing six-membered ring and a phenyldibenzofuranyl group or a phenyldibenzothiophene group in indolocarbazole and a biscarbazole compound as a second host.

[0246] Explanation of symbols

[0247] 1: Substrate

[0248] 2: Anode

[0249] 3: Hole injection layer

[0250] 4: Hole transport layer

[0251] 5: Luminous layer

[0252] 6: Electron transport layer

[0253] 7: Cathode

Claims

1. An organic electric field light-emitting element, comprising one or more light-emitting layers between an anode and a cathode facing each other, wherein at least one light-emitting layer contains: a first host selected from a compound represented by the following general formula (1); a second host selected from a compound represented by the following general formula (2); and a light-emitting dopant material. [Chemistry 1] (Herein, ring G is an aromatic ring represented by formula (1a), and is condensed with two adjacent rings; ring H is a heterocyclic ring represented by formula (1b), and is condensed with two adjacent rings at any position but not on the side including N; X is independently N, CH, or CR, and at least one is N; and Y is O or S. Ar 1 It represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group in which two to five aromatic rings of an aromatic group selected from the above aromatic hydrocarbon groups and the above aromatic heterocyclic groups are linked. Ar 2 independently represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 17 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group in which two to five aromatic rings of an aromatic group selected from the above aromatic hydrocarbon groups and the above aromatic heterocyclic groups are linked. in, Ar 1 and two Ar 2 At least one of them represents a group represented by formula (1c), and * represents a bonding position. L 1 represents a single bond, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, R 1 each independently represents deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking 2 to 5 aromatic rings of an aromatic group selected from the aromatic hydrocarbon group and the aromatic heterocyclic group, wherein R 1 When it is an aromatic hydrocarbon group, it can be 1 The bonded benzene rings are condensed to form a ring. R 2 each independently represents deuterium or an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a to f represent the number of substitutions, a and b each independently represent an integer of 0 to 4, c represents an integer of 0 to 2, d each independently represents an integer of 0 to 13, e represents an integer of 0 to 3, f each independently represents an integer of 0 to 4, and n represents the number of repetitions and represents an integer of 1 to 4.) [Chemistry 2] (Here, Ar 3 , and Ar 4 Each independently represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group in which two to five aromatic rings of these aromatic groups are linked. Each independently represents a single bond, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, and R 3 , R 6 , and R 7 Each of them independently represents deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, g to j and p to q represent the number of substitutions, g and h independently represent an integer of 0 to 4, i and j independently represent an integer of 0 to 3, and p and q independently represent 0 to 12.

2. The organic electroluminescent element according to claim 1, characterized in that: All of the X are N.

3. The organic electroluminescent element according to claim 1, characterized in that: The Ar 2 At least one of is represented by any one of formulas (3) to (5). [Chemistry 3] (Here, *, Y, R 2 , e, f and n have the same meanings as in the general formula (1c).

4. The organic electroluminescent element according to claim 3, characterized in that: The Ar 2 At least one of them is a group represented by formula (3).

5. The organic electroluminescent element according to claim 1, characterized in that: Said Y is O.

6. The organic electroluminescent element according to claim 1, characterized in that: The compound represented by the general formula (1) is represented by any one of the following formulas (6) to (9). [Chemistry 4] (Here, Ar 1 ,Ar 2 , L 1 , R 1 , R 2 , a, b, c and d have the same meanings as in the general formula (1).

7. The organic electroluminescent element according to claim 1, characterized in that: The R 1 For deuterium.

8. The organic electroluminescent element according to claim 1, characterized in that: The R 2 For deuterium.

9. The organic electroluminescent element according to claim 1, characterized in that: The general formula (2) is represented by the following formula (10). [Chemistry 5] (Here, Ar 3 ,Ar 4 , L, R 3 , R 6 , R 7 , g to j, and p to q have the same meanings as in the general formula (2).

10. The organic electroluminescent element according to claim 1, wherein the Ar 3 and Ar 4 are each independently a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, or a substituted or unsubstituted terphenyl group.

11. The organic electroluminescent element according to claim 1, characterized in that: The R 3 For deuterium.

12. The organic electroluminescent element according to any one of claims 1 to 11, characterized in that: The light-emitting dopant material is an organic metal complex containing at least one metal selected from ruthenium, rhodium, palladium, silver, rhenium, osmium, iridium, platinum and gold.

13. The organic electroluminescent element according to any one of claims 1 to 11, characterized in that: The luminescent dopant material is a thermally activated delayed fluorescent luminescent dopant material.

14. A premixture comprising a first host and a second host, used to form a light-emitting layer in an organic electric field light-emitting element, wherein the organic electric field light-emitting element includes the light-emitting layer containing the host and a light-emitting dopant material between opposite anode and cathode, wherein the premixture is characterized in that the first host is selected from a compound represented by the following general formula (1), and the second host is selected from a compound represented by the following general formula (2). [Chemistry 6] (Here, ring G is an aromatic ring represented by formula (1a), and ring H is a heterocyclic ring represented by formula (1b). X is independently N, CH, or CR, and at least one of them is N. Y is O or S. Ar 1 It represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group in which two to five aromatic rings of an aromatic group selected from the above aromatic hydrocarbon groups and the above aromatic heterocyclic groups are linked. Ar 2 Each independently represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 17 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group in which 2 to 5 aromatic rings of an aromatic group selected from the aromatic hydrocarbon group and the aromatic heterocyclic group are linked, wherein: Ar 1 and two Ar 2 At least one of them is a group represented by formula (1c). L each independently represents a single bond, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, and R 1 each independently represents deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking 2 to 5 aromatic rings of an aromatic group selected from the aromatic hydrocarbon group and the aromatic heterocyclic group, wherein R 1 When it is an aromatic hydrocarbon group, it can be 1 The bonded benzene rings condense to form a ring, R 2 each independently represents deuterium or an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a to f represent the number of substitutions, a and b each independently represent an integer of 0 to 4, c represents an integer of 0 to 2, d each independently represents an integer of 0 to 13, e represents an integer of 0 to 3, f each independently represents an integer of 0 to 4, and n represents the number of repetitions and represents an integer of 1 to 4.) [Chemistry 7] (Here, Ar 3 , and Ar 4 Each independently represents an aromatic hydrocarbon group having 6 to 18 carbon atoms, an aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group in which two to five of these aromatic groups are linked. Each independently represents a single bond, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, and R 3 , R 6 , and R 7 Each of them independently represents deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, g to j and p to q represent the number of substitutions, g and h independently represent an integer of 0 to 4, i and j independently represent an integer of 0 to 3, and p and q independently represent 0 to 12.

15. The premix according to claim 14, characterized in that The difference between the 50% weight reduction temperatures of the first body and the second body is within 20°C.

16. A method for manufacturing an organic electroluminescent element, characterized in that: When manufacturing the organic electroluminescent element according to any one of claims 1 to 13, the process comprises the following steps: after mixing the first host and the second host to prepare a premix, vapor-depositing a host material including the premix to form a light-emitting layer.

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