Hybrid composition and organic electroluminescent element

Abstract

Provided are: a practically useful organic EL element which has a low driving voltage, high efficiency, and a long service life; and a material suitable for the organic EL element. A mixed composition containing a compound represented by general formula (1) and a compound represented by general formula (2), the compound represented by general formula (1) being an indolocarbazole compound having a structure in which a substituted triazine ring is bonded to one N of an indolocarbazole ring and a phenyl-substituted ortho-phenylene group is bonded to the other N, the compound represented by general formula (2) is a bicarbazole compound having a structure in which an aromatic hydrocarbon group is substituted on the N of the carbazole ring.

Description

Technical Field

[0001] The present invention relates to a mixed composition and an organic electroluminescent element (referred to as an organic EL element) using the mixed composition. Specifically, it relates to a mixed composition containing an indolocarbazole compound and a dicarbazole compound, and an organic EL element using the mixed composition. Background Art

[0002] By applying a voltage to an organic electroluminescence element (referred to as an organic EL element), holes are injected into the light-emitting layer from the anode, and electrons are injected into the light-emitting layer from the cathode. Moreover, in the light-emitting layer, the injected holes and electrons recombine 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 a fluorescent organic EL element that uses light emission generated by singlet excitons, it is considered that the limit of the internal quantum efficiency is 25%. On the other hand, it is known that in a phosphorescent organic EL element that uses light emission generated by triplet excitons, when intersystem crossing is efficiently performed from singlet excitons, the internal quantum efficiency is increased to 100%.

[0003] However, regarding phosphorescent organic EL elements, extending the lifetime has become a technical issue.

[0004] Furthermore, recently, highly efficient organic EL elements utilizing delayed fluorescence have been developed. For example, Patent Document 1 discloses an organic EL element that utilizes the Triplet-Triplet Fusion (TTF) mechanism, which is one of the mechanisms of delayed fluorescence. The TTF mechanism utilizes the phenomenon of generating singlet excitons through the collision of two triplet excitons and is considered to theoretically increase the internal quantum efficiency to 40%. However, when compared with phosphorescent organic EL elements, the efficiency is low, and thus further improvement in efficiency is required.

[0005] On the other hand, Patent Document 2 discloses an organic EL element that utilizes the Thermally Activated Delayed Fluorescence (TADF) mechanism. The TADF mechanism is a mechanism that utilizes the phenomenon of reverse intersystem crossing from triplet excitons to singlet excitons in a material with a small energy difference between the singlet energy level and the triplet energy level, and is considered to theoretically increase the internal quantum efficiency to 100%. However, similar to phosphorescent elements, further improvement in lifetime characteristics is required.

[0006] Prior Art Documents

[0007] Patent document

[0008] Patent document 1: WO2010 / 134350

[0009] Patent document 2: WO2011 / 070963

[0010] Patent document 3: WO2008 / 056746

[0011] Patent document 4: KR Patent Publication No. 2013 / 132226

[0012] Patent document 5: Japanese Patent Laid-Open No. 2003-133075

[0013] Patent document 6: US Patent Publication 2014 / 0197386

[0014] Patent document 7: US Patent Publication 2015 / 0001488

[0015] Patent document 8: US Patent Publication 2008 / 0286605

[0016] Patent document 9: WO2016 / 194604

[0017] Patent document 10: WO2018 / 198844

[0018] Patent document 11: WO2018 / 061446

[0019] Patent document 12: WO2022 / 255243

[0020] Patent document 13: WO2023 / 008501

[0021] The use of indolocarbazole compounds as host materials is disclosed in Patent Document 3 and Patent Document 4. The use of biscarbazole compounds as host materials is disclosed in Patent Document 5.

[0022] The use of indolocarbazole compounds and biscarbazole compounds as a mixed host is disclosed in Patent Document 6 and Patent Document 7. In addition, the use of deuterated carbazole compounds as host materials is disclosed in Patent Document 8.

[0023] The use of a mixed composition of multiple indolocarbazole compounds and biscarbazole compounds as a host material is disclosed in Patent Document 9, Patent Document 10, and Patent Document 11.

[0024] The use of a mixed composition of multiple indolocarbazole compounds and deuterated biscarbazole compounds as a host material is disclosed in Patent Document 12.

[0025] In Patent Document 13, a mixed composition of a specified indolocarbazole compound and a deuterated dicarbazole compound is disclosed as a host material.

[0026] However, in terms of achieving a reduction in the driving voltage of the device, an improvement in luminous efficiency, and a longer lifespan, it cannot be said to be sufficient, and further improvement is desired. Summary of the Invention

[0027] Problems to be Solved by the Invention

[0028] In order to apply an organic EL device to display devices such as flat panel displays, it is necessary to sufficiently ensure the long lifespan characteristics of the device while improving the luminous efficiency of the device. In view of the above situation, an object of the present invention is to provide a practically useful organic EL device with a low driving voltage, high efficiency, and long lifespan, and a compound suitable therefor.

[0029] Technical Means for Solving the Problems

[0030] The inventors of the present invention conducted intensive research and as a result, found that by using a mixed composition of a specific indolocarbazole compound and a dicarbazole compound in an organic EL device, excellent characteristics are exhibited, thereby completing the present invention.

[0031] The present invention is a mixed composition containing a compound represented by the general formula (1) and a compound represented by the following general formula (2).

[0032] [Chemical Formula 1]

[0033]

[0034] Here, ring A is a heterocycle represented by the formula (1a) condensed with two adjacent rings at an arbitrary position. Ar 1 and Ar 2 are each independently a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted terphenyl group, or a substituted or unsubstituted quaterphenyl group. The total number of benzene rings contained in Ar 1 and Ar 2 is preferably 2 - 6, more preferably 2 - 4.

[0035] R 1 are each independently a substituted or unsubstituted aromatic hydrocarbon group having 6 - 10 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 - 12 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to five of these aromatic groups. The aromatic hydrocarbon group or aromatic heterocyclic group during linking may be the same or different from each other.

[0036] a to c represent the number of substituents, where a and c are integers from 0 to 4, b is an integer from 0 to 2, preferably a and c are integers from 0 to 2, and b is an integer from 0 to 1. x is the number of substituents, an integer from 0 to 5, preferably from 0 to 3, more preferably from 0 to 2, and even more preferably from 0 to 1. Additionally, when x is from 2 to 5, since it becomes a bulky substituent, intermolecular interactions can be suppressed, and the effect of forming a film with high amorphous stability can be expected.

[0037] [Chemical Formula 2]

[0038]

[0039] Here, Ar 3 and Ar 4 each independently represent a substituted or unsubstituted aromatic hydrocarbon group having 6 to 14 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two of these aromatic hydrocarbon groups. The aromatic hydrocarbon groups during linking can be the same or different. Ar 3 and Ar 4 are preferably a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted naphthyl group, or a substituted or unsubstituted phenanthryl group, and more preferably an unsubstituted phenyl group.

[0040] Additionally, L 1 and L 2 each independently represent a direct bond or a substituted or unsubstituted phenylene group. y and z each independently represent an integer from 1 to 2, preferably y = z = 1. When y or z is 2, L 1 or L 2 is not a direct bond, and the phenylene group becomes a trivalent phenylene group.

[0041] The mixed composition is preferably such that, relative to the total of the compound represented by the general formula (1) and the compound represented by the general formula (2), the compound represented by the general formula (1) is 20 wt% or more and 70 wt% or less.

[0042] At least one of the compound represented by the general formula (1) or the compound represented by the general formula (2) is preferably such that part or all of the hydrogen is substituted with deuterium.

[0043] Additionally, in the compound represented by the general formula (1) or the general formula (2), when part or all of the hydrogen is substituted with deuterium, the average deuteration rate is preferably 30% or more, and more preferably 40% or more.

[0044] It can be that the mixed composition is a material for at least one layer for manufacturing an organic electroluminescent element by a vapor deposition method, and is a premix premixed before vapor deposition.

[0045] In the pre-mixture, the difference between the 50% weight reduction temperatures of the compound represented by the general formula (1) and the compound represented by the general formula (2) is preferably within 20 °C.

[0046] Furthermore, the present invention relates to an organic electroluminescent device having a plurality of organic layers between an anode and a cathode, and is characterized in that at least one of the organic layers contains the mixed composition.

[0047] Preferably, the organic layer containing the mixed composition is at least one layer selected from the group consisting of a light-emitting layer, a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, a hole blocking layer, and an electron blocking layer, and more preferably a light-emitting layer. In addition, when the organic layer containing the mixed composition is a light-emitting layer, the light-emitting layer preferably contains at least one light-emitting dopant, and further preferably contains the compound represented by the general formula (1) as a first host and the compound represented by the general formula (2) as a second host, and the light-emitting layer contains at least one light-emitting dopant.

[0048] Furthermore, the present invention relates to a method for manufacturing an organic electroluminescent device, which is a method for manufacturing an organic electroluminescent device having a plurality of organic layers including a light-emitting layer between an anode and a cathode, and is characterized by having the following steps: preparing the above-mentioned mixed composition, evaporating and depositing it from one evaporation source using the mixed composition, thereby forming a light-emitting layer.

[0049] Effects of the Invention

[0050] In order to improve the characteristics of an organic EL device, it is necessary for the materials used in the organic layers to have high durability against charges. In particular, in the light-emitting layer, it is important to suppress the leakage of excitons and charges to the surrounding layers. For suppressing the leakage of the charges / excitons, it is effective to improve the shift of the light-emitting region in the light-emitting layer. For this purpose, it is necessary to control the injection amounts of the two charges (electrons / holes) into the light-emitting layer or the transportability of the two charges in the light-emitting layer within a preferable range.

[0051] The injection and transportability of the two charges of the materials used in the organic layers are greatly affected by the energy levels of the molecular orbitals of the materials and the magnitude of the intermolecular interactions. When the mixed composition of the present invention is used as a material for an organic EL device, since it contains an indolocarbazole compound having an ortho-linked biphenyldiyl represented by the formula (1a), the electron injection and transport ability is particularly high. However, due to the steric hindrance effect of the biphenyldiyl, the approach of indolocarbazole molecules to each other can be suppressed.

[0052] Moreover, it is considered that by changing the type or bonding position of the substituents of the biphenyldiyl, the intermolecular interaction of the molecular orbitals that contribute greatly to the electron injection and transport to the light-emitting layer can be controlled at a high level, thereby providing an excellent organic EL device. Description of the Drawings

[0053] Figure 1 is a cross-sectional view showing an example of the structure of an organic EL element. Detailed Description of the Invention

[0054] The hybrid composition of the present invention comprises the compound represented by the general formula (1) and the compound represented by the general formula (2).

[0055] In the general formula (1), ring A is a five-membered heterocyclic ring represented by the formula (1a), and the heterocyclic ring is condensed with two adjacent rings at an arbitrary position, but not condensed on the side containing N. Therefore, the indolocarbazole ring has several isomeric structures, but the number thereof is limited.

[0056] Specifically, as the compound represented by the general formula (1), there is an aspect represented by any one of the following formulas (3) to (8), preferably formulas (6) to (8), and more preferably the structure represented by formula (8). In addition, in formulas (3) to (8), the notations common to the general formula (1) have the same meanings.

[0057] [Chemical Formula 3]

[0058]

[0059] In the general formula (1), Ar 1 and Ar 2 are each independently a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted terphenyl group, or a substituted or unsubstituted quaterphenyl group. Preferably, the sum of the number of benzene rings of Ar 1 and Ar 2 is 5 or less, and more preferably 4 or less. The biphenyl group, terphenyl group, or quaterphenyl group has a structure in which two, three, or four benzene rings are connected, but the bonding positions of each benzene ring can be any of ortho, meta, and para positions. In addition, it can be linear or branched.

[0060] R 1 are each independently a substituted or unsubstituted aromatic hydrocarbon group having 6 to 10 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 12 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to five of these aromatic groups. When linking, the aromatic hydrocarbon groups or aromatic heterocyclic groups can be the same or different from each other.

[0061] ​In this specification, a linked aromatic group refers to an aromatic group formed by bonding and linking the aromatic rings of two or more aromatic groups with single bonds. These linked aromatic groups may be linear or branched. When benzene rings are linked to each other, the linking position may be any of ortho, meta, or para positions, but para-linking or meta-linking is preferred. The aromatic group may be an aromatic hydrocarbon group or an aromatic heterocyclic group, and multiple aromatic groups may be the same or different.

[0062] As R 1 Specific examples of an unsubstituted aromatic hydrocarbon group having 6 to 10 carbon atoms, an unsubstituted aromatic heterocyclic group having 3 to 12 carbon atoms, or an unsubstituted linked aromatic group formed by linking two to five of these aromatic groups include groups generated from compounds formed by linking 2 to 5 of benzene, naphthalene, pyridine, pyrimidine, triazine, thiophene, isothiazole, thiazole, pyridazine, pyrrole, pyrazole, imidazole, triazole, thiadiazole, pyrazine, furan, isoxazole, quinoline, isoquinoline, quinoxaline, quinazoline, thiadiazole, phthalazine, dibenzofuran, dibenzothiophene, dibenzoselenophene, carbazole, or the like.

[0063] In this specification, the aromatic hydrocarbon group, the aromatic heterocyclic group, or the linked aromatic group may each have a substituent. When having a substituent, the substituent is preferably deuterium, a halogen, a cyano group, a triarylsilyl group, 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 linear, branched, or cyclic. When the triarylsilyl group or the diarylamino group becomes a substituent of the aromatic hydrocarbon group, the aromatic heterocyclic group, or the linked aromatic group, silicon and carbon, or nitrogen and carbon are bonded with a single bond, respectively.

[0064] In addition, the number of the substituents is preferably 0 to 5, more preferably 0 to 2. Further, when calculating the number of carbon atoms in the case where the aromatic hydrocarbon group and the aromatic heterocyclic group have substituents, the number of carbon atoms of the substituents is not included. However, it is preferred that the total number of carbon atoms including the carbon atoms of the substituents satisfies the above range.

[0065] Specific examples of the substituent include deuterium, a cyano group, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a tert-butyl group, a pentyl group, a neopentyl group, a cyclopentyl group, a hexyl group, a cyclohexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, a vinyl group, an allyl group, a butenyl group, a pentenyl group, a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a diphenylamino group, a naphthylphenylamino group, a dinaphthylamino group, a dianthrylamino group, a diphenanthrylamino group, a dipyrenylamino group, etc. Preferred examples include deuterium, a cyano group, a methyl group, an ethyl group, a tert-butyl group, a propyl group, a butyl group, a pentyl group, a neopentyl group, a hexyl group, a heptyl group, an octyl group, or an octyldiphenylamino group, a naphthylphenylamino group, or a dinaphthylamino group.

[0066] Specific examples of the general formula (1) are shown below, but are not limited to these exemplified compounds. In addition, in the following structural formulas, the substitution number n of the substituted deuterium (D) refers to the average number and varies according to the average deuteration rate.

[0067] [Chemical formula 4]

[0068]

[0069] [Chemical formula 5]

[0070]

[0071] [Chemical formula 6]

[0072]

[0073] [Chemical formula 7]

[0074]

[0075] [Chemical formula 8]

[0076]

[0077] [Chemical formula 9]

[0078]

[0079] [Chemical formula 10]

[0080]

[0081] [Chemical formula 11]

[0082]

[0083] [Chemical formula 12]

[0084]

[0085] [Chemical formula 13]

[0086]

[0087] [Chemical formula 14]

[0088]

[0089] [Chemical formula 15]

[0090]

[0091] [Chemical formula 16]

[0092]

[0093] [Chemical Formula 17]

[0094]

[0095] [Chemical Formula 18]

[0096]

[0097] [Chemical Formula 19]

[0098]

[0099] [Chemical Formula 20]

[0100]

[0101] [Chemical Formula 21]

[0102]

[0103] [Chemical Formula 22]

[0104]

[0105] [Chemical Formula 23]

[0106]

[0107] [Chemical Formula 24]

[0108]

[0109] [Chemical Formula 25]

[0110]

[0111] [Chemical Formula 26]

[0112]

[0113] [Chemical Formula 27]

[0114]

[0115] [Chemical Formula 28]

[0116]

[0117] [Chemical Formula 29]

[0118]

[0119] [Chemical Formula 30]

[0120]

[0121] [Chemical Formula 31]

[0122]

[0123] [Chemical Formula 32]

[0124]

[0125] [Chemical Formula 33]

[0126]

[0127] Among these specifically exemplified compounds, preferred examples include compounds 104, 106, 108, 110, 111, 112, 114, 116, 117, 118, 119, 120, 121, 123, 125, 126, 127, 128, 129, 192, 201, 208, 220, 301, 302, 303, 304, 305, 306, 307, 308, 309, 310, 311, 312, 313, 314, 331, 340, 341, 342, 343, 348, 349, 350, 354, 355, 356, 360, 361, and 362.

[0128] In the general formula (2), Ar 3 and Ar 4 each independently represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 14 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two of these aromatic hydrocarbon groups. Preferred are a substituted or unsubstituted aromatic hydrocarbon group having 6 to 10 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two of these aromatic hydrocarbon groups. More preferred are a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted naphthyl group, or a substituted or unsubstituted phenanthryl group, and even more preferred is an unsubstituted phenyl group. The biphenyl group has a structure formed by linking two benzene rings, and the bonding position of each benzene ring can be any of ortho, meta, and para positions.

[0129] In Ar 3 and Ar 4 as specific examples of the unsubstituted aromatic hydrocarbon group having 6 to 14 carbon atoms or the unsubstituted linked aromatic group formed by linking two of these aromatic groups, groups derived from compounds formed by benzene, naphthalene, phenanthrene, or linking two of these can be cited.

[0130] L 1 and L 2 represent a direct bond or a substituted or unsubstituted phenylene group. The phenylene group can be any of ortho-bonded, meta-bonded, and para-bonded.

[0131] y and z represent the number of substitutions and independently represent 1 or 2, preferably 1. In the case of 2, L 1 or L 2 is a trivalent phenylene group.

[0132] Specific examples of the general formula (2) are shown below, but are not limited to these exemplified compounds. In addition, in the following structural formulas, the meanings of D and m are the same as those of the aforementioned n.

[0133] [Chemical formula 34]

[0134]

[0135] [Chemical formula 35]

[0136]

[0137] [Chemical formula 36]

[0138]

[0139] [Chemical formula 37]

[0140]

[0141] [Chemical formula 38]

[0142]

[0143] [Chemical formula 39]

[0144]

[0145] Among these specifically exemplified compounds, preferred examples include compounds 602, 603, 605, 606, 607, 608, 609, 610, 611, 613, 615, 616, 617, 618, 619, 620, 701, 702, 703, 704, 705, 706, 707, 708, 709, 710, 711, 712, 713, and 714.

[0146] The hydrogen in the compounds contained in the mixed composition of the present invention may be deuterium. That is, in the general formula (1), the hydrogen in the condensed ring (indolocarbazole ring) containing ring A, the hydrogen in the biphenyl or terphenyl substituted on the indolocarbazole ring, and Ar 1 Ar 2 , and R 1 in the aromatic rings of, and a part or all of the hydrogen in the substituents substituted on these aromatic rings may be deuterium. In addition, the hydrogen in the two carbazole rings of the compound represented by the general formula (2), or Ar 3 Ar4 , L 1 and L 2 and the hydrogen of the aromatic ring in L 3 , Ar 4 , L 1 and L 2 Part or all of the hydrogen of the substituents possessed by may be deuterium.

[0147] In addition, in the case of deuterides in which part or all of the hydrogen of these compounds is deuterated, the compounds represented by the general formula (1) or the general formula (2) include both the case of containing a single compound and the case of a mixture containing two or more compounds. That is, the compounds represented by the general formula (1) or the general formula (2) may be two or more of the compounds contained in these formulas, or may be a mixture of compounds having different deuteration numbers or deuteration positions.

[0148] In addition, all of the compounds contained in the mixed composition may be deuterated, or only some of the compounds may be deuterated.

[0149] For the compounds represented by the general formula (1) or the general formula (2), the average deuteration rate is preferably 30% or more, more preferably 40% or more.

[0150] Here, when specifically explaining the average deuteration rate, when the average deuteration rate is 50%, it means that on average half of all the hydrogens are substituted with deuterium.

[0151] The average deuteration rate can be determined by mass analysis or proton nuclear magnetic resonance spectroscopy. For example, in the case of determining by proton nuclear magnetic resonance spectroscopy, first, a measurement sample is prepared by adding the compound and an internal standard substance to a deuterated solvent and dissolving them. According to the integral intensity ratio of the internal standard substance and the compound source, the proton concentration [mol / g] of the compound contained in the measurement sample is calculated. 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, whereby the average deuteration rate of the deuterated compound can be calculated.

[0152] The mixed composition of the present invention contains the compound represented by the general formula (1) and the compound represented by the general formula (2), and the mixing ratio (weight ratio) thereof, with respect to the total of the two, the compound represented by the general formula (1) is preferably 20 wt% to 70 wt%, more preferably 20 wt% to 60 wt%.

[0153] In addition to the compound represented by the general formula (1) and the compound represented by the general formula (2), the mixed composition may contain other compounds. As the other compounds, there are known host materials, luminescent dopants, etc. However, the compound represented by the general formula (1) and the compound represented by the general formula (2) should preferably be 50 wt% or more, more preferably 75 wt% or more, of the whole.

[0154] The mixed composition of the present invention is suitable as a material or component of an organic EL element.

[0155] When it becomes a component of an organic EL element, the mixed composition is contained in the organic layer of the organic EL element. As the organic layer, it is preferably selected from the group consisting of a light-emitting layer, a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, a hole blocking layer, and an electron blocking layer. Preferably it is a light-emitting layer, and the light-emitting layer preferably contains at least one luminescent dopant.

[0156] When the mixed composition of the present invention is contained in the light-emitting layer, it is preferably contained as the host of the light-emitting layer. Advantageously, the compound represented by the general formula (1) is preferably contained as the first host, and the compound represented by the general formula (2) is contained as the second host.

[0157] When the mixed composition of the present invention is made into a component of an organic EL element, the following method may also be adopted: evaporating the compound represented by the general formula (1) and a plurality of compounds such as the compound represented by the general formula (2) from different evaporation sources respectively, and performing evaporation plating, etc. However, it is preferably pre-mixed before evaporation plating to form a pre-mixture, and then the pre-mixture is simultaneously evaporated from one evaporation source and evaporated to form an organic layer, preferably to form a light-emitting layer.

[0158] When using the pre-mixture to form a light-emitting layer as the mixed composition of the present invention, a required luminescent dopant material or other host materials used as needed can be mixed. However, when there is a large difference in the temperature at which the desired vapor pressure exists, it is preferably to evaporate the luminescent dopant material or other host from different evaporation sources.

[0159] When the mixed composition of the present invention is the pre-mixture, in order to perform evaporation plating stably, the 50% weight loss temperature of the compound represented by the general formula (1) and the compound represented by the general formula (2) is preferably within 20 °C. More preferably within 15 °C.

[0160] The organic EL element of the present invention has a plurality of organic layers between opposing electrodes, and at least one of the organic layers is a light-emitting layer. At least one light-emitting layer preferably contains the mixed composition as the host. When the light-emitting layer contains the mixed composition, it preferably contains at least one luminescent dopant.

[0161] Next, the structure of the organic EL element of the present invention will be described with reference to the accompanying drawings, but the structure of the organic EL element of the present invention is not limited thereto.

[0162] Figure 1 FIG. 1 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, or may be inserted into both sides simultaneously. In the organic EL element of the present invention, an anode, a light-emitting layer, and a cathode are provided as essential layers. However, in addition to the essential layers, a hole injection / transport layer and an electron injection / transport layer are preferably provided, and a hole blocking layer is preferably provided between the light-emitting layer and the electron injection / transport layer. In addition, the hole injection / transport layer means either one or both of the hole injection layer and the hole transport layer, and the electron injection / transport layer means either one or both of the electron injection layer and the electron transport layer.

[0163] It can also be Figure 1 a reverse structure, that is, a cathode 7, an electron transport layer 6, a light-emitting layer 5, a hole transport layer 4, a hole injection layer 3, and an anode 2 are sequentially stacked on the substrate 1. In this case, layers can also be added or omitted as needed.

[0164] - Substrate -

[0165] The organic EL element of the present invention is preferably supported on a substrate. The substrate is not particularly limited as long as it has been used for organic EL elements before. For example, a substrate containing glass, transparent plastic, quartz, etc. can be used.

[0166] - Anode -

[0167] As an anode material in an organic EL element, a material containing a metal, alloy, conductive compound, or a mixture thereof having 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), SnO2, ZnO, and other conductive transparent materials. In addition, amorphous materials such as IDIXO (In2O3-ZnO) that can form a transparent conductive film can also be used. The anode can be formed by methods such as evaporation or sputtering to form a thin film of these electrode materials, and a pattern of a desired shape can be formed using photolithography. Or, when the pattern accuracy is not very required (about 100 μm or more), a mask of a desired shape can be interposed during the evaporation or sputtering of the electrode materials to form a pattern. Or, in the case of using a material that can be coated such as an organic conductive compound, wet film-forming methods such as printing and coating methods can also be used. When light is emitted from the anode, it is desirable that the transmittance is greater than 10%, and the sheet resistance of the anode is preferably several hundred Ω / square or less. The film thickness also depends on the material and is usually selected in the range of 10 nm to 1000 nm, preferably 10 nm to 200 nm.

[0168] - Cathode -

[0169] As a cathode material, a material containing a metal (electron injection metal), alloy, conductive compound, or a mixture thereof having a small work function (4 eV or less) can be used. Specific examples of such electrode materials include sodium, sodium-potassium alloy, magnesium, lithium, magnesium / copper mixture, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, aluminum / aluminum oxide (Al2O3) mixture, indium, lithium / aluminum mixture, rare earth metals, etc. Among these, in terms of electron injection properties and durability against oxidation and the like, a mixture of an electron injection metal and a second metal having a larger and more stable work function value than it, such as a magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, aluminum / aluminum oxide mixture, lithium / aluminum mixture, aluminum, etc., is suitable. The cathode can be fabricated by forming a thin film of these cathode materials using methods such as evaporation or sputtering. In addition, as the cathode, the sheet resistance is preferably several hundred Ω / square or less, and the film thickness is usually selected in the range of 10 nm to 5 μm, preferably 50 nm to 200 nm. Furthermore, in order to allow the emitted light to pass through, it is appropriate if either the anode or the cathode of the organic EL element is transparent or translucent, thereby increasing the emission brightness.

[0170] In addition, after forming the metal on the cathode with a film thickness of 1 nm to 20 nm, a conductive transparent material listed in the description of the anode is formed thereon, whereby a transparent or translucent cathode can be fabricated. By applying the method, an element having light transmissivity for both the anode and the cathode can be fabricated.

[0171] -Light-emitting layer-

[0172] The light-emitting layer is a layer that emits light after excitons are generated by recombination of holes and electrons respectively injected from the anode and the cathode, and the light-emitting layer contains a light-emitting dopant material and a host.

[0173] The hybrid composition of the present invention can be suitably used as a material for an organic electroluminescent element, preferably as a host. Preferably, a compound represented by the general formula (1) is used as the first host and a compound represented by the general formula (2) is used as the second host in the host. One kind of the first host or the second host can be used, or two or more different compounds can be used. According to need, one or more other known host materials can also be used in combination, but the amount used is preferably 50 wt% or less, more preferably 25 wt% or less, based on the total amount of the host materials.

[0174] The method for manufacturing the organic electroluminescent element of the present invention includes the following steps: preparing the above-mentioned premix; and evaporating the premix from one evaporation source and depositing it to form a light-emitting layer. Moreover, a method of vaporizing the premix from a single evaporation source and depositing it is more preferably used. Here, the premix is preferably a uniform composition.

[0175] When the first host and the second host are premixed and used, in order to fabricate an organic EL element with good characteristics with good reproducibility, it is desirable that the difference in the 50% weight loss temperature (T50) is small. The 50% weight loss temperature refers to the temperature at which the weight decreases by 50% when the temperature is raised from room temperature to 550 °C at a rate of 10 °C per minute in a thermogravimetry-differential thermal analysis (TG-DTA) measurement under reduced pressure of nitrogen gas (1 Pa). It is considered that gasification caused by evaporation or sublimation is most intense near the above temperature.

[0176] When the difference in the 50% weight loss temperature is within 20 °C, when the premix is vaporized from a single evaporation source and deposited, a uniform deposited film can be obtained, so it is preferred. At this time, a light-emitting dopant material required to form a light-emitting layer or other hosts used as needed can also be mixed in the premix.

[0177] As a method for preparing a premix by premixing, a method that can be mixed as uniformly as possible is desirable. Examples include pulverization mixing, or a method of heating and melting under reduced pressure or in an inert gas environment such as nitrogen, or sublimation, etc., but the method is not limited to these.

[0178] The form of the premix can be powder, rod-shaped, or granular.

[0179] When the compound represented by the general formula (1) or the compound represented by the general formula (2) is a deuteride, methods of manufacturing using all or part of deuterated starting materials and methods of manufacturing by hydrogen / deuterium exchange reaction are known. All or part of the deuterated raw materials can be purchased from commercial supply sources or manufactured by known hydrogen / deuterium exchange reactions. As known hydrogen / deuterium exchange reactions, there are methods of allowing deuterium gas or its equivalent to act on a non-deuterated body in the presence of a transition metal catalyst, or methods of treating a non-deuterated body with a deuterated solvent (such as deuterated benzene) in the presence of an acid catalyst, etc.

[0180] When using a phosphorescent light-emitting dopant as the light-emitting dopant material, as the phosphorescent light-emitting dopant, it is preferable to contain an organometallic complex containing at least one metal selected from ruthenium, rhodium, palladium, silver, rhenium, osmium, iridium, platinum, and gold. Specifically, iridium complexes described in Journal of the American Chemical Society (J.Am.Chem.Soc.) 2001, 123, 4304, JP2013-530515A, US2016 / 0049599A, US2017 / 0069848A, US2018 / 0282356A, or US2019 / 0036043A, etc., or platinum complexes described in US2018 / 0013078A, or KR2018-094482A, etc. can be suitably used, but it is not limited to these.

[0181] The phosphorescent light-emitting dopant material may contain only one kind in the light-emitting layer or may contain two or more kinds. The content of the phosphorescent light-emitting dopant material is preferably 0.1 wt% to 30 wt%, more preferably 1 wt% to 20 wt% relative to the host material.

[0182] The phosphorescent light-emitting dopant material is not particularly limited, and specifically, compounds such as the following can be cited.

[0183] [Chemical formula 40]

[0184]

[0185] [Chemical formula 41]

[0186]

[0187] [Chemical formula 42]

[0188]

[0189] In the case of using a fluorescent light-emitting dopant as the light-emitting dopant material, there is no particular limitation on the fluorescent light-emitting dopant. For example, examples include: benzoxazole derivatives, benzothiazole derivatives, benzimidazole derivatives, styrylbenzene derivatives, polyphenyl derivatives, diphenylbutadiene derivatives, tetraphenylbutadiene derivatives, naphthalenedicarboximide derivatives, coumarin derivatives, condensed aromatic compounds, perinone derivatives, oxadiazole derivatives, oxazine derivatives, aldazine derivatives, pyrrolidine derivatives, cyclopentadiene derivatives, bisstyrylanthracene derivatives, quinacridone derivatives, pyrrolopyridine derivatives, thiadiazolopyridine derivatives, styrylamine derivatives, diketopyrrolopyrrole derivatives, aromatic methylene compounds, metal complexes of 8-hydroxyquinoline derivatives or metal complexes of pyrromethene derivatives, rare earth complexes, various metal complexes represented by transition metal complexes, etc., polythiophene, polyphenylene, poly(phenylacetylene) and other polymer compounds, organosilane derivatives, etc. Preferred examples include condensed aromatic derivatives, styryl derivatives, diketopyrrolopyrrole derivatives, oxazine derivatives, pyrromethene metal complexes, transition metal complexes, or lanthanide complexes. More preferred examples include naphthalene, pyrene, , triphenylene, benzo[c]phenanthrene, benzo[a]anthracene, pentacene, perylene, fluoranthene, acenaphthenequinone, dibenzo[a,j]anthracene, dibenzo[a,h]anthracene, benzo[a]naphthalene, hexacene, naphtho[2,1-f]isoquinoline, α-naphthaphenanthridine, phenoxazole, quinoline[6,5-f]quinoline, benzonaphtho[2,3-b]thiophene, etc. These may also have an alkyl group, an aryl group, an aromatic heterocyclic group, or a diarylamino group as a substituent.

[0190] In the case of using a thermally activated delayed fluorescence (TADF) light-emitting dopant as the light-emitting dopant material, there is no particular limitation on the TADF light-emitting dopant. Examples include: metal complexes such as tin complexes or copper complexes, or indolocarbazole derivatives described in WO2011 / 070963A, cyanobenzene derivatives described in "Nature" 2012, 492, 234, carbazole derivatives, phenazine derivatives described in "Nature Photonics" 2014, 8, 326, oxadiazole derivatives, triazole derivatives, sulfone derivatives, phenoxazine derivatives, acridine derivatives, etc.

[0191] There is no particular limitation on the thermally activated delayed fluorescence light-emitting dopant material. Specifically, examples of the compound are as follows.

[0192] [Chemical formula 43]

[0193]

[0194] The thermally activated delayed fluorescence (TADF) emitting dopant material may contain only one kind or two or more kinds in the light-emitting layer. In addition, the TADF emitting dopant may be used in combination with a phosphorescent emitting dopant or a fluorescent emitting dopant. The content of the TADF emitting dopant material is preferably 0.1 wt% to 50 wt%, more preferably 1 wt% to 30 wt% relative to the host material.

[0195] - Injection layer -

[0196] The so-called injection layer is a layer provided between the electrode and the organic layer to reduce the driving voltage or increase the light-emitting luminance. There are a hole injection layer and an electron injection layer, which may 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.

[0197] - Hole blocking layer -

[0198] Broadly speaking, the so-called hole blocking layer has the function of an electron transport layer, and includes a hole blocking material having the function of transporting electrons and significantly small ability to transport holes. The recombination probability of electrons and holes in the light-emitting layer can be increased by transporting electrons and blocking holes.

[0199] - Electron blocking layer -

[0200] Broadly speaking, the so-called electron blocking layer has the function of a hole transport layer, and can increase the recombination probability of electrons and holes in the light-emitting layer by transporting holes and blocking electrons.

[0201] As the material of the electron blocking layer, known electron blocking layer materials can be used. In addition, materials of the hole transport layer described later can be used as needed. The film thickness of the electron blocking layer is preferably 3 nm to 100 nm, more preferably 5 nm to 30 nm.

[0202] - Exciton blocking layer -

[0203] The so-called exciton blocking layer is a layer for blocking the diffusion of excitons generated by the recombination of holes and electrons in the light-emitting layer to the charge transport layer. By inserting this layer, excitons can be efficiently enclosed in the light-emitting layer, and the luminous efficiency of the device can be improved. The exciton blocking layer can be inserted between two adjacent light-emitting layers in a device with two or more adjacent light-emitting layers.

[0204] As the material of the exciton blocking layer, known exciton blocking layer materials can be used. For example, 1,3 - dicarbazolylbenzene (mCP), or bis(8 - hydroxy - 2 - methylquinoline)-(4 - phenylphenoxy)aluminum(III) (BAlq), etc. can be cited.

[0205] -Hole transport layer-

[0206] The so-called hole transport layer contains a hole transport material having the function of transporting holes, and the hole transport layer can be provided as a single layer or multiple layers.

[0207] As the hole transport material, it is a material having any one of the functions of hole injection or transport and electron barrier properties, and can be either an organic material or an inorganic material. Any one can be selected from previously known compounds and used in the hole transport layer. 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, stilbene derivatives, silazane derivatives, aniline-based copolymers, and conductive polymer oligomers, especially thiophene oligomers, etc. are exemplified. It is preferably to use porphyrin derivatives, arylamine derivatives and styrylamine derivatives, and more preferably to use arylamine derivative compounds.

[0208] -Electron transport layer-

[0209] The so-called electron transport layer contains a material having the function of transporting electrons, and the electron transport layer can be provided as a single layer or multiple layers.

[0210] As the electron transport material (sometimes also serving as a hole blocking material), it only needs to have the function of transferring the electrons injected from the cathode to the light-emitting layer. Any one can be selected from previously known compounds and used in the electron transport layer. 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, thianthrene dioxide derivatives, carbodiimide, fluoreneylidene methane derivatives, anthraquinone dimethane derivatives and anthrone derivatives, bipyridine derivatives, quinoline derivatives, oxadiazole derivatives, benzimidazole derivatives, benzothiazole derivatives, indolocarbazole derivatives, etc. are exemplified. Furthermore, a polymer material in which these materials are introduced into the polymer chain or these materials are used as the main chain of the polymer can also be used.

[0211] Examples

[0212] Hereinafter, the present invention will be described in more detail by way of examples. However, the present invention is not limited to these examples and can be implemented in various forms as long as it does not exceed the gist thereof.

[0213] Synthesis Example 1

[0214] [Chemical formula 44]

[0215]

[0216] To 5 g of compound (a), 5.6 g of compound (b), 8.6 g of tripotassium phosphate, and 60 ml of 1,3-dimethyl-2-imidazolidinone were added, and the mixture was stirred at 200 °C for 48 hours under a nitrogen atmosphere. After cooling to room temperature, it was purified by silica gel column chromatography and recrystallization purification to obtain 6.6 g (yield 70%) of intermediate (1-1) in the form of a white solid.

[0217] Under a nitrogen atmosphere, a suspension was prepared by adding 1.3 g of 60 wt% sodium hydride to 30 ml of N,N'-dimethylacetamide. To this, 6 g of intermediate (1-1) dissolved in 170 mL of N,N'-dimethylacetamide was added, and the mixture was stirred for 30 minutes. After adding 5.1 g of compound (c) thereto, the mixture was stirred for 6 hours. The reaction solution was added to a mixed solution of methanol (300 ml) and distilled water (100 ml) while stirring, and the precipitated solid obtained was separated by filtration. The obtained solid was purified by silica gel column chromatography and recrystallization purification to obtain 6.5 g (yield 66%) of compound 114 (APCI-TOFMS, m / z 792 [M+H]+) in the form of a yellow solid.

[0218] Synthesis Example 2

[0219] Compound 405 was synthesized according to the following reaction.

[0220] [Chemical Formula 45]

[0221]

[0222] To 8.3 g of compound 608, 160 ml of deuterated benzene (C6D6) and 10.0 g of deuterated trifluoromethanesulfonic acid (Trifluoromethane sulfonic acid, TfOD) were added, and the mixture was heated and stirred at 50 °C for 6.5 hours under a nitrogen atmosphere. The reaction solution was quenched by adding it to a deuterated aqueous solution (200 ml) of sodium carbonate (7.4 g), and separated and purified to obtain 2.5 g of compound 705 as a deuterated white solid.

[0223] For compound 705, the average degree of deuteration was determined by proton nuclear magnetic resonance spectroscopy. A measurement sample was prepared by dissolving compound 405 (5.0 mg) and dimethyl sulfoxide (2.0 mg) as an internal standard substance in deuterated tetrahydrofuran (1.0 ml). The average proton concentration [mol / g] of compound 705 contained in the measurement sample was calculated based on the integral intensity ratio between the internal standard substance and compound 705. Similarly, the average proton concentration [mol / g] of the non-deuterated form of compound 705 (compound 608) was also calculated. Next, the ratio of the proton concentration of compound 705 to the proton concentration of compound 608 was calculated and subtracted from 1, whereby the average degree of deuteration of compound 705 was found to be 68.8%.

[0224] Synthesis Example 3

[0225] [Chemical Formula 46]

[0226]

[0227] To 8.4 g of compound (1-1), 200 ml of deuterated benzene (C6D6) and 12.7 g of deuterated trifluoromethanesulfonic acid (TfOD) were added, and the mixture was heated and stirred at 50 °C for 4 hours under a nitrogen atmosphere. The reaction solution was quenched by adding it to an aqueous deuterated solution (130 ml) of sodium carbonate (10.2 g), and separated and purified to obtain 6.8 g of compound (1-1-D) as a deuterated product.

[0228] [Chemical Formula 47]

[0229]

[0230] Under a nitrogen atmosphere, a suspension was prepared by adding 1.8 g of 60 wt% sodium hydride to 45 ml of N,N'-dimethylacetamide. To this, 6.9 g of intermediate (1-1-D) dissolved in 240 mL of N,N'-dimethylacetamide was added and stirred for 30 minutes. After adding 6.0 g of compound (c) thereto, the mixture was stirred for 6 hours. The reaction solution was added to a mixed solution of methanol (400 ml) and distilled water (150 ml) while stirring, and the solid obtained after precipitation was separated by filtration. The obtained solid was purified by silica gel column chromatography and recrystallization purification to obtain 7.8 g (yield 69%) of compound 306 as a yellow solid.

[0231] For Compound 306, the average deuteration rate was determined by proton nuclear magnetic resonance spectroscopy. A measurement sample was prepared by dissolving Compound 218 (5.0 mg) and dimethyl sulfone (2.0 mg) as an internal standard substance in deuterated tetrahydrofuran (1.0 ml). The average proton concentration [mol / g] of Compound 306 contained in the measurement sample was calculated based on the integral intensity ratio of the internal standard substance to the source of Compound 306. Similarly, the average proton concentration [mol / g] of the non-deuterated form (Compound 114) of Compound 306 was also calculated. Next, the ratio of the proton concentration of Compound 306 to the proton concentration of Compound 114 was calculated and subtracted from 1, whereby the average deuteration rate of Compound 306 was found to be 53.4%.

[0232] Synthesis Example 4

[0233] The reaction was carried out in the same manner as in Synthesis Examples 2 to 3 to synthesize Compounds 701, 707, 301, 309, 310, 331, and 340 as deuterides. In addition, similar to 705 and 306, the results of calculating the average deuteration rates of these are shown in Table 1.

[0234] [Table 1]

[0235] Compound Average deuteration rate 705 68.8％ 701 74.0％ 707 68.6％ 306 53.4％ 301 44.5％ 309 52.4％ 310 52.8％ 331 58.5％ 340 82.3％

[0236] The compounds used in the Examples and Comparative Examples are shown below.

[0237] [Chemical Formula 48]

[0238]

[0239] Example 1

[0240] On a glass substrate having an anode containing ITO with a film thickness of 110 nm, each thin film was laminated by vacuum evaporation at a vacuum degree of 4.0×10 -5 Pa.

[0241] First, as a hole injection layer on ITO, Compound A and Compound B were co-evaporated from separate evaporation sources to form a thickness of 10 nm. At this time, co-evaporation was carried out under the evaporation conditions where the concentration of Compound B became 3 wt%.

[0242] Next, Compound A was formed to a thickness of 110 nm as the first hole transport layer.

[0243] Next, Compound C was formed to a thickness of 10 nm as the second hole transport layer.

[0244] Next, Compound D was formed to a thickness of 5 nm as an electron blocking layer.

[0245] Next, a premix of compound 114 (the first host) and compound 608 (the second host) as the main body was evaporated from a single evaporation source, compound E as the light-emitting dopant was evaporated from a different evaporation source, and co-evaporation was carried out to form the light-emitting layer to a thickness of 40 nm. At this time, co-evaporation was carried out under the evaporation conditions where the concentration of compound E was 15 wt% and the weight ratio of the first host to the second host was 50:50.

[0246] Next, compound F was formed to a thickness of 5 nm as the hole blocking layer.

[0247] Next, compound G was formed to a thickness of 30 nm as the electron transport layer.

[0248] Furthermore, LiF was formed to a thickness of 1 nm as the electron injection layer on the electron transport layer.

[0249] Finally, on the electron injection layer, Al was formed to a thickness of 70 nm as the cathode, thereby fabricating an organic EL element.

[0250] Examples 2 to 30, Comparative Examples 1 to 8

[0251] As the first host and the second host, the compounds shown in Table 2 were used and set to the weight ratios shown in Table 2, and an organic EL element was fabricated in the same manner as in Example 1 except for this.

[0252] The evaluation results of the fabricated organic EL elements are shown in Table 2. In the table, the luminance, voltage, and current efficiency are the values at a driving current of 10 mA / cm 2 and are the initial characteristics. LT70 is the time taken for the luminance to decay to 70% when driven at an initial luminance of 9000 nits, representing the lifetime characteristics. The numbers of the first host and the second host are the numbers attached to the exemplified compounds, and the weight ratio is the first host: the second host. In addition, any characteristics are marked with relative values with the characteristics of Comparative Example 1 set to 100%.

[0253] [Table 2]

[0254]

[0255]

[0256] Examples 31 to 50, Comparative Examples 9 to 14

[0257] As the first host and the second host, the compounds shown in Table 3 were used and co-evaporated from separate evaporation sources at the weight ratios shown in Table 3, and an organic EL element was fabricated in the same manner as in Example 1 except for this.

[0258] For the obtained organic EL elements, evaluation was carried out in the same manner as in the previous Example 1 and the like. The results are shown in Table 3. In addition, any characteristic is marked with a relative value with the characteristic of Comparative Example 9 set to 100%.

[0259] [Table 3]

[0260]

[0261] From the above results, it can be seen that in Examples 1 to 50, while maintaining the same lifetime characteristics as in the comparative examples, the efficiency is improved, showing good characteristics. Generally, efficiency and lifetime are sometimes in a trade-off relationship, and it is difficult to improve both current efficiency and lifetime characteristics. Among them, improving current efficiency is related to low power consumption or increased brightness. Therefore, if current efficiency can be improved while obtaining a certain level of lifetime characteristics, it can become a more practical element. From this point of view, in Examples 1 to 50 using the hybrid composition of the present invention, compared with Comparative Examples 1 and 9 in which a previous compound was used for a part of the host material, about 90% of the lifetime characteristics can be maintained, or more than 100% of the lifetime characteristics can be exhibited, and at the same time, a current efficiency of more than 110% can be achieved, and a practically advantageous organic EL element can be obtained.

[0262] In addition, the 50% weight loss temperature (T50) of Compounds 104, 114, 121, 123, 301, 309, 310, 318, 602, 608, 701, 705, 707, 192, 331, 201, 340, 208, 220, H, I, J, and K is described in Table 4.

[0263] [Table 4]

[0264] Compound T50[℃] 608 275 705 278 602 265 701 267 707 269 114 265 306 268 104 277 301 275 121 263 309 263 123 272 310 271 192 264 331 264 201 295 340 295 208 273 220 271 H 268 I 267 J 286 K 285

[0265] Explanation of reference numerals

[0266] 1: Substrate

[0267] 2: Anode

[0268] 3: Hole injection layer

[0269] 4: Hole transport layer

[0270] 5: Light-emitting layer

[0271] 6: Electron transport layer

[0272] 7: Cathode

Claims

1. A mixed composition comprising a compound represented by the following general formula (1) and a compound represented by the following general formula (2). [Chemical formula 1] (Here, ring A is a heterocyclic ring represented by formula (1a) condensed with two adjacent rings at any position. Ar 1 and Ar 2 are each independently a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted terphenyl group, or a substituted or unsubstituted quaterphenyl group. R 1 are each independently a substituted or unsubstituted aromatic hydrocarbon group having 6 to 10 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 12 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to five of these aromatic groups, and the aromatic hydrocarbon group or aromatic heterocyclic group at the time of linking may be the same or different from each other. a to c are the number of substituents, a and c are each independently an integer of 0 to 4, b is an integer of 0 to 2. x is the number of substituents and is an integer of 0 to 5.) [Chemical formula 2] (Here, Ar 3 and Ar 4 each independently represent a substituted or unsubstituted aromatic hydrocarbon group having 6 to 14 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two of these aromatic hydrocarbon groups, and the aromatic hydrocarbon groups at the time of linking may be the same or different. L 1 and L 2 each independently represent a direct bond or a substituted or unsubstituted phenylene group. y and z represent the number of substitutions and each independently represent an integer of 1 to 2).

2. The hybrid composition according to claim 1, characterized in that, Based on the total of the compound represented by the general formula (1) and the compound represented by the general formula (2), the compound represented by the general formula (1) is 20 wt% or more and 70 wt% or less.

3. The mixed composition according to claim 1, wherein in at least one of the compounds represented by the general formula (1) and the general formula (2), part or all of the hydrogen is substituted with deuterium.

4. The mixed composition according to claim 1, wherein in the compound represented by the general formula (2), part or all of the hydrogen is substituted with deuterium, and its average deuteration rate is 30% or more.

5. The hybrid composition according to claim 1, characterized in that, The mixed composition is a material for at least one layer used to manufacture an organic electroluminescent element by a vapor deposition method, and is a premix premixed before vapor deposition.

6. The hybrid composition according to claim 5, wherein The difference in the 50% weight loss temperature between the compound represented by the general formula (1) and the compound represented by the general formula (2) is within 20 °C.

7. An organic electroluminescent element having a plurality of organic layers between an anode and a cathode, characterized in that at least one layer of the organic layers contains the mixed composition according to any one of claims 1 to 6.

8. The organic electroluminescent element according to claim 7, wherein the organic layer containing the mixed composition is at least one layer selected from the group consisting of a light-emitting layer, a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, a hole blocking layer, and an electron blocking layer.

9. The organic electroluminescent element according to claim 7, wherein the organic layer containing the mixed composition is a light-emitting layer, containing the compound represented by the general formula (1) as a first host and the compound represented by the general formula (2) as a second host, and the light-emitting layer contains at least one light-emitting dopant.

10. A method for manufacturing an organic electroluminescent device, which is a method for manufacturing an organic electroluminescent device having a plurality of organic layers including a light-emitting layer between an anode and a cathode, wherein the method for manufacturing the organic electroluminescent device is characterized by comprising the following steps, and the steps include: Prepare the mixed composition according to claim 5; and evaporate the mixed composition from one evaporation source and deposit it to form a light-emitting layer.

11. The mixed composition according to claim 1, wherein in the compound represented by the general formula (1), the substitution number x is an integer of 0 to 2.

12. The hybrid composition according to claim 1, wherein the compound represented by the general formula (1) is any one selected from the group consisting of the following, where n represents the average number of substituted deuteriums (D) and varies according to the average deuteration rate. [Chemical formula 3] [Chemical formula 4] [Chemical formula 5] [Chemical formula 6] [Chemical formula 7] [Chemical formula 8] [Chemical formula 9] [Chemical formula 10] [Chemical formula 11] [Chemical formula 12] [Chemical formula 13] 13. The hybrid composition according to claim 1, wherein the compound represented by the general formula (1) is any one selected from the group consisting of the following, where n represents the average number of substituted deuteriums (D) and varies according to the average deuteration rate. [Chemical formula 14] [Chemical formula 15] [Chemical formula 16] [Chemical formula 17] [Chemical formula 18] [Chemical formula 19] [Chemical formula 20] [Chemical formula 21] [Chemical formula 22] 14. The hybrid composition according to claim 1, wherein the compound represented by the general formula (2) is any one selected from the group consisting of the following. Among them, m represents the average number of substituted deuteriums (D) and varies according to the average deuteration rate. [Chemical formula 23] [Chemical formula 24] [Chemical formula 25] [Chemical formula 26] [Chemical formula 27]

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