Luminescent material composition and organic electroluminescent device

Abstract

The present invention belongs to the technical field of organic electronic devices, and specifically discloses a luminescent material composition, wherein the composition comprises a first metal complex and a second metal complex, and the first metal complex and the second metal complex are different from each other, and the first metal complex and the second metal complex are each independently selected from the compound represented by formula (I). The present invention also provides an organic electroluminescent device prepared using the luminescent material composition, which has lower voltage, higher efficiency and longer life.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic devices, and in particular to a luminescent material composition and an organic electroluminescent device prepared using the composition. Background Art

[0002] Organic electronic devices include but are not limited to the following categories: organic light emitting diodes (OLEDs), organic field effect transistors (O-FETs), organic light emitting transistors (OLETs), organic photovoltaic devices (COPVs), dye-sensitized solar cells (DSSCs), organic optical detectors, organic photoreceptors, organic field effect devices (OFQDs), light emitting electrochemical cells (LEGS), organic laser diodes and organic plasmonic light emitting devices.

[0003] In 1987, Tang et al. from Eastman Kodak Company in the United States first reported a green electroluminescent device made of a double-layer organic film. The device used indium tin oxide (ITO) as the anode, and a 75nm thick amorphous pinhole-free aromatic diamine film was evaporated on the anode for hole transport. Then, a 60nm thick 8-hydroxyquinoline aluminum film was plated on the aromatic diamine film to serve as an electron transport layer and light-emitting layer. The magnesium-silver alloy was used as the cathode. This double-layer film structure successfully reduced the turn-on voltage to 5.5V, achieved high radiant luminescence (>1000cd·m-2), a wavelength of 550nm, and an external quantum efficiency of 1.0%, which has great practical significance. In 1994, KH1do et al. from Japan prepared a white-light-emitting organic electroluminescent device for the first time. They doped blue, green and orange fluorescent dyes into poly(N-vinyl carbazole) (PVK) film as hole transport layer and emission layer, 1,2,4-triazole derivative (TAZ) as hole blocking layer, 8-hydroxyquinoline aluminum (Alq3) as electron transport layer, and the device composition was: glass substrate / ITO / PVK / TAZ / Alq3 / Mg:Ag multilayer structure. At a driving voltage of 14V, white light emission with a wide range of visible light and a brightness of up to 3400cd·m-2 was obtained. This high-brightness white emission was achieved by doping a polymer film with fluorescent compounds of various colors to form a single emission layer. This discovery by KIdo et al. has added a strong and colorful touch to the application of organic electroluminescence, opened the door to organic light-emitting devices in the field of lighting, and promoted the further development of organic light-emitting devices.

[0004] The light emitted by organic electroluminescent devices is divided into fluorescence and phosphorescence. The light emitted by the energy of singlet excitons is fluorescence, while the light emitted by the energy of both singlet and triplet excitons is phosphorescence. Since the number of singlet and triplet states formed by excitons has a fixed ratio of 1:3, theoretically, the internal quantum efficiency of a fluorescent device that only uses singlet excitons is only 25% at most, while the internal quantum efficiency of phosphorescence can reach 100%.

[0005] At present, organometallic complexes and organic electroluminescent devices with phosphorescent emission have been reported, but in many applications such as TV and lighting equipment, the life of OLED is insufficient, and more efficient OLED is still needed. Typically, the higher the brightness of the OLED, the shorter the life of the OLED. Therefore, for long-term use and high-resolution displays, OLEDs with high luminous efficiency or long life are needed.

[0006] A large number of phosphorescent materials are disclosed in the prior art. Some of these materials have a long lifespan and some have a high external quantum efficiency when used in organic electroluminescent devices. However, they often cannot have both lifespan and efficiency. In practical applications, they need to be selected according to the needs.

[0007] Through in-depth research, the present inventors have found that by using at least two luminescent guest materials with specific structures in the luminescent layer at the same time, an organic electroluminescent device with significantly improved comprehensive performance can be obtained. Summary of the invention

[0008] The present invention aims to provide a novel organic electroluminescent device, the light-emitting layer of which contains a variety of guest light-emitting materials and has excellent properties such as high purity, high brightness and high efficiency.

[0009] Specifically, in a first aspect, the present invention provides a luminescent material composition, comprising a first metal complex and a second metal complex; the first metal complex and the second metal complex are different and are each independently selected from the structure represented by general formula (1):

[0010]

[0011] in:

[0012] R 1 ~R 11 are independently selected from hydrogen atoms, deuterium atoms, substituted or unsubstituted alkyl groups, deuterated alkyl groups, substituted or unsubstituted alkoxy groups, substituted or unsubstituted alkylamino groups, substituted or unsubstituted alkylthio groups, halogen atoms, substituted or unsubstituted alicyclic hydrocarbon groups, substituted or unsubstituted aromatic groups and substituted or unsubstituted heterocyclic aromatic groups, and the substituted substituents are selected from C 1 ~C 10Straight or branched alkyl, halogen atom, C 1 ~C 10 Straight-chain or branched deuterated alkyl, C 6 ~C 20 The aromatic and C 3 ~C 20 and / or, R 1 ~R 11 Any two or more groups are connected by bridging to form a ring structure;

[0013] R' and R" are independently selected from hydrogen atom, substituted or unsubstituted alkyl, deuterated alkyl, halogen atom, substituted or unsubstituted alicyclic hydrocarbon group, substituted or unsubstituted alkoxy group, substituted or unsubstituted alkylamino group, substituted or unsubstituted alkylthio group and substituted or unsubstituted aromatic group, and the substituted substituent is selected from C 1 ~C 10 Straight or branched alkyl, halogen atom, C 1 ~C 10 Straight-chain or branched deuterated alkyl, C 6 ~C 20 The aromatic and C 3 ~C 20 heteroaryl;

[0014] L is a monovalent bidentate anionic ligand, wherein the bonding atoms X and Y are independently selected from oxygen atoms, nitrogen atoms, and carbon atoms;

[0015] n is 1, 2 or 3;

[0016] The weight ratio of the first metal complex to the second metal complex is 1:(0.01-99).

[0017] The weight ratio of the first metal complex to the second metal complex is 1:(0.25-5), preferably 1:(0.5-2), and more preferably 1:(0.8-1.3).

[0018] As a preferred embodiment of the present invention, L is phenylpyridyl, substituted phenylpyridyl, acetylacetonyl or substituted acetylacetonyl.

[0019] More preferably, L is a group represented by formula L1 or formula L2:

[0020]

[0021] Among them, in formula L1, R 12 ~R 19are independently selected from hydrogen atoms, deuterium atoms, substituted or unsubstituted alkyl groups, deuterated alkyl groups, substituted or unsubstituted alkoxy groups, substituted or unsubstituted alkylamino groups, substituted or unsubstituted alkylthio groups, halogen atoms, substituted or unsubstituted alicyclic hydrocarbon groups, substituted or unsubstituted aromatic groups and substituted or unsubstituted heterocyclic aromatic groups, and the substituted substituents are selected from C 1 ~C 10 Straight or branched alkyl, halogen atom, C 1 ~C 10 Straight-chain or branched deuterated alkyl, C 6 ~C 20 The aromatic and C 3 ~C 20 The substituted substituent is selected from C 1 ~C 10 Straight or branched alkyl, halogen atom, C 1 ~C 10 Straight-chain or branched deuterated alkyl, C 6 ~C 20 The aromatic and C 3 ~C 20 and / or, R 12 ~R 19 Any two or more groups are connected by bridging to form a ring structure;

[0022] In formula L2, R 20 ~R 26 are independently selected from hydrogen atoms, deuterium atoms, substituted or unsubstituted alkyl groups, deuterated alkyl groups, substituted or unsubstituted alkoxy groups, substituted or unsubstituted alkylamino groups, substituted or unsubstituted alkylthio groups, halogen atoms, substituted or unsubstituted alicyclic hydrocarbon groups, substituted or unsubstituted aromatic groups and substituted or unsubstituted heterocyclic aromatic groups, and the substituted substituents are selected from C 1 ~C 10 Straight or branched alkyl, halogen atom, C 1 ~C 10 Straight-chain or branched deuterated alkyl, C 6 ~C 20 The aromatic and C 3 ~C 20 The substituted substituent is selected from C 1 ~C 10 Straight or branched alkyl, halogen atom, C 1 ~C 10 Straight-chain or branched deuterated alkyl, C 6 ~C 20 The aromatic and C 3 ~C 20 and / or, R 20 ~R26 Any two or more groups are connected by bridges to form a ring structure.

[0023] As a preferred embodiment of the present invention, the iridium complex containing a benzimidazole structure is a compound represented by general formula I, general formula II or general formula III:

[0024]

[0025] Where m is 1 or 2,

[0026] R in Formula I, Formula II, and Formula III 1 ~R 26 and R′, R″ are as defined above.

[0027] As a preferred embodiment of the present invention, the R 1 ~R 11 are independently selected from hydrogen atoms, deuterium atoms, C 1 ~C 5 Straight-chain or branched alkyl, deuterated C 1 ~C 5 Straight or branched alkyl, C 5 ~C 20 alicyclic hydrocarbon groups, halogen atoms, alkoxy groups containing 1 to 5 C atoms, alkylamino groups containing 1 to 5 C atoms, alkylthio groups containing 1 to 5 C atoms, halogenated alkyl groups containing 1 to 5 C atoms such as trifluoromethyl, substituted or unsubstituted C 6 ~C 18 Aryl such as phenyl, substituted phenyl, substituted or unsubstituted C 3 ~C 18 and / or, R 1 ~R 11 Any two or more groups in the formula (a) are connected by a bridge to form a ring structure, wherein the ring structure is any one of a substituted or unsubstituted five-membered ring, a substituted or unsubstituted six-membered ring, a substituted or unsubstituted five-membered heterocycle and a substituted or unsubstituted six-membered heterocycle, and the substituents used are halogen atoms, C 1 ~C 5 Straight-chain or branched alkyl, phenyl, deuterated C 1 ~C 5 The five-membered heterocyclic ring or the six-membered heterocyclic ring contains at least one heteroatom, and the heteroatom is arbitrarily selected from an oxygen atom and a sulfur atom.

[0028] As a preferred embodiment of the present invention, said R' and R" are independently selected from hydrogen atoms, C 1 ~C 5Straight-chain or branched alkyl, deuterated C 1 ~C 5 Straight or branched alkyl, C 5 ~C 20 alicyclic hydrocarbon groups, halogen atoms, alkoxy groups containing 1 to 5 C atoms, alkylamino groups containing 1 to 5 C atoms, alkylthio groups containing 1 to 5 C atoms, trifluoromethyl groups, substituted or unsubstituted C 6 ~C 12 The aryl group may include, for example, phenyl and substituted phenyl.

[0029] As a preferred embodiment of the present invention, the R 12 ~R 19 are independently selected from hydrogen atoms, deuterium atoms, C 1 ~C 5 Straight-chain or branched alkyl, deuterated C 1 ~C 5 Straight or branched alkyl, C 3 ~C 20 alicyclic hydrocarbon groups, halogen atoms, alkoxy groups containing 1 to 5 C atoms, alkylamino groups containing 1 to 5 C atoms, alkylthio groups containing 1 to 5 C atoms, 1 ~C 5 haloalkyl such as trifluoromethyl, substituted or unsubstituted C 6 ~C 18 Aryl such as phenyl, substituted phenyl, substituted or unsubstituted C 3 ~C 18 and / or, R 12 ~R 19 Any two or more groups in the formula (a) are connected by a bridge to form a ring structure, wherein the ring structure is any one of a substituted or unsubstituted five-membered ring, a substituted or unsubstituted six-membered ring, a substituted or unsubstituted five-membered heterocycle and a substituted or unsubstituted six-membered heterocycle, and the substituent used is C 1 ~C 5 Straight-chain or branched alkyl, deuterated C 1 ~C 5 The five-membered heterocyclic ring or the six-membered heterocyclic ring contains at least one heteroatom, and the heteroatom is arbitrarily selected from an oxygen atom and a sulfur atom.

[0030] As a preferred embodiment of the present invention, the R 20 ~R 26 are independently selected from hydrogen atoms, deuterium atoms, C 1 ~C 5 Straight-chain or branched alkyl, deuterated C 1 ~C5 A linear or branched alkyl group, a halogen atom, an alkoxy group containing 1 to 5 C atoms, an alkylamino group containing 1 to 5 C atoms, an alkylthio group containing 1 to 5 C atoms, a 1 ~C 5 The haloalkyl group is for example trifluoromethyl.

[0031] As a further preferred embodiment of the present invention, the R 1 ~R 11 are independently selected from hydrogen atoms, deuterium atoms, C 1 ~C 5 Straight-chain or branched alkyl, deuterated C 1 ~C 5 Straight or branched alkyl, C 5 ~C 12 alicyclic hydrocarbon groups, halogen atoms, substituted or unsubstituted C 6 ~C 12 Aryl such as phenyl, substituted phenyl, substituted or unsubstituted C 3 ~C 12 heteroaryl such as pyridyl, substituted pyridyl; and / or, R 1 ~R 11 Any two or more groups in the formula (a) are connected by a bridge to form a ring structure, wherein the ring structure is any one of a substituted or unsubstituted six-membered ring such as a benzene ring, a substituted or unsubstituted five-membered heterocycle, and the substituents used are halogen atoms, C 1 ~C 5 Straight-chain or branched alkyl, deuterated C 1 ~C 5 The five-membered heterocyclic ring contains at least one heteroatom, and the heteroatom is arbitrarily selected from oxygen atom and sulfur atom.

[0032] More preferably, the R 1 ~R 11 are independently selected from hydrogen, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, adamantyl, cyclooctyl, deuterated methyl, deuterated ethyl, phenyl, fluorine, and bromine; and / or, R 1 ~R 11 Any two or more groups are bridged to form a ring structure, wherein the ring structure is any one of a substituted or unsubstituted benzene ring, a substituted or unsubstituted furan ring, and a substituted or unsubstituted thiophene ring, and the substituent used is a benzo group.

[0033] As a further preferred embodiment of the present invention, said R' and R" are independently selected from hydrogen atoms, C 1 ~C 5Straight-chain or branched alkyl, deuterated C 1 ~C 5 Straight or branched alkyl, C 5 ~C 10 alicyclic hydrocarbon groups, halogen atoms, substituted or unsubstituted C 6 ~C 12 The aryl group is, for example, phenyl and substituted phenyl.

[0034] More preferably, the R' and R" are independently selected from hydrogen atom, methyl group, ethyl group, n-propyl group, isopropyl group, fluorine atom, deuterated methyl group, cyclohexyl group and phenyl group.

[0035] As a further preferred embodiment of the present invention, the R 12 ~R 19 are independently selected from hydrogen atoms, deuterium atoms, C 1 ~C 5 Straight-chain or branched alkyl, deuterated C 1 ~C 5 Straight or branched alkyl, C 5 ~C 12 alicyclic hydrocarbon groups, halogen atoms, substituted or unsubstituted C 6 ~C 12 Aryl such as phenyl, substituted phenyl, substituted or unsubstituted C 3 ~C 12 heteroaryl such as pyridyl, substituted pyridyl; and / or, R 12 ~R 19 Any two or more groups in the formula (a) are connected by a bridge to form a ring structure, wherein the ring structure is any one of a substituted or unsubstituted six-membered ring, a substituted or unsubstituted five-membered heterocycle, and the substituents used are halogen atoms, C 1 ~C 5 Straight-chain or branched alkyl, deuterated C 1 ~C 5 The five-membered heterocyclic ring contains at least one heteroatom, and the heteroatom is arbitrarily selected from oxygen atom and sulfur atom.

[0036] More preferably, the R 12 ~R 19 are independently selected from hydrogen, fluorine, methyl, ethyl, isopropyl, n-propyl, n-butyl, tert-butyl, sec-butyl, isobutyl, adamantyl, deuterated methyl, phenyl, halogen or C 1 ~C 5 phenyl substituted by an alkyl radical, such as tolyl, xylyl, monofluorophenyl, bromophenyl, difluorophenyl; and / or, R 12~R 19 Any two or more groups in the formula (a) are connected by a bridge to form a ring structure, wherein the ring structure is any one of a substituted or unsubstituted six-membered ring and a substituted or unsubstituted five-membered heterocyclic ring, and the substituents used are bromine atoms, fluorine atoms, phenyl, benzoyl, methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, sec-butyl, isobutyl, pyrido, C 1 ~C 5 Alkyl or C 1 ~C 5 The five-membered heterocyclic ring contains at least one heteroatom, and the heteroatom is arbitrarily selected from oxygen atom and sulfur atom.

[0037] As a further preferred embodiment of the present invention, the R 20 ~R 26 are independently selected from hydrogen atoms, deuterium atoms, C 1 ~C 5 Straight-chain or branched alkyl, deuterated C 1 ~C 5 Straight chain or branched alkyl group, halogen atom.

[0038] More preferably, the R 20 ~R 26 Each is independently selected from a hydrogen atom, a methyl group and an ethyl group.

[0039] More preferably, L is arbitrarily selected from the following groups:

[0040]

[0041] As a preferred embodiment of the present invention, the first metal complex and the second metal complex are independently selected from the compounds represented by the following structural formulas:

[0042]

[0043]

[0044]

[0045]

[0046]

[0047]

[0048]

[0049] As a preferred embodiment of the present invention, the first metal complex and the second metal complex are both selected from the compounds represented by general formula I.

[0050] As a preferred embodiment of the present invention, the first metal complex and the second metal complex are both selected from the compounds shown in general formula I, and m of the first metal complex is the same as m of the second metal complex, for example, m of the first metal complex and m of the second metal complex are both 1 or m of the first metal complex and m of the second metal complex are both 2. Preferably, R′, R″, R 1 ~R 19 and R′, R″, R 1 ~R 19 At least one of is the same.

[0051] As a more preferred embodiment of the present invention, the first metal complex and the second metal complex are both selected from the compounds shown in the general formula I, m of the first metal complex is the same as m of the second metal complex, and R′, R″, R 1 ~R 11 and R′, R″, R 1 ~R 11 At least one of the first metal complex is the same as 12 ~R 19 The second metal complex R 12 ~R 19 In some embodiments, at least one of R′, R″, R 1 ~R 11 and R′, R″, R 1 ~R 11 any one of the same or any two of the same or any three of the same or any four of the same or any five of the same or any six of the same or any seven of the same or any eight of the same or any nine of the same or any ten of the same or any eleven of the same or any twelve of the same or all of the same. In some embodiments, R of the first metal complex 12 ~R 19 The second metal complex R 12 ~R 19 Any one of them is the same, or any two are the same, or any three are the same, or any four are the same, or any five are the same, or any six are the same, or any seven are the same, or all are the same.

[0052] As a more preferred embodiment of the present invention, the first metal complex and the second metal complex are both selected from the compounds shown in the general formula I, m of the first metal complex is the same as m of the second metal complex, and R′, R″, R 1 ~R 11 and R′, R″, R 1 ~R 11 Any one of the groups is different, and the remaining 12 groups are the same, and R of the first metal complex 12 ~R 19 The second metal complex R 12 ~R 19 Any one of the groups is different and each is independently selected from a hydrogen atom, a deuterium atom, a C 1 ~C 5 Straight-chain or branched alkyl, deuterated C 1 ~C 5 Straight or branched alkyl, C 5 ~C 12 alicyclic hydrocarbon groups, halogen atoms, substituted or unsubstituted C 6 ~C 12 Aryl, substituted or unsubstituted C 3 ~C 12 The remaining 7 groups are the same.

[0053] As a more preferred embodiment of the present invention, the first metal complex and the second metal complex are both selected from the compounds shown in general formula I, m of the first metal complex is the same as m of the second metal complex, R' and R" of the first metal complex are the same as R' and R" of the second metal complex, and R of the first metal complex is 1 ~R 11 The second metal complex R 1 ~R 11 Any one of the groups is different and each is independently selected from a hydrogen atom, a deuterium atom, a C 1 ~C 5 Straight-chain or branched alkyl, deuterated C 1 ~C 5 Straight or branched alkyl, C 5 ~C 12 alicyclic hydrocarbon groups, halogen atoms, substituted or unsubstituted C 6 ~C 12 Aryl, substituted or unsubstituted C 3 ~C 12 The remaining 10 groups are the same, and R 12 ~R 19The second metal complex R 12 ~R 19 Any one of the groups is different and each is independently selected from a hydrogen atom, a deuterium atom, a C 1 ~C 5 Straight-chain or branched alkyl, deuterated C 1 ~C 5 Straight or branched alkyl, C 5 ~C 12 alicyclic hydrocarbon groups, halogen atoms, substituted or unsubstituted C 6 ~C 12 Aryl, substituted or unsubstituted C 3 ~C 12 The remaining 7 groups are the same.

[0054] As a more preferred embodiment of the present invention, the first metal complex and the second metal complex are both selected from the compounds shown in general formula I, m of the first metal complex is the same as m of the second metal complex, and R of the first metal complex 12 ~R 19 The second metal complex R 12 ~R 19 are the same, and R′, R″, R 1 ~R 11 and R′, R″, R 1 ~R 11 In some embodiments, R′, R″, R 1 ~R 11 and R′, R″, R 1 ~R 11 Any one is the same or any two are the same or any three are the same or any four are the same or any five are the same or any six are the same or any seven are the same or any eight are the same or any nine are the same or any ten are the same or any eleven are the same or any twelve are the same.

[0055] As a more preferred embodiment of the present invention, the first metal complex and the second metal complex are both selected from the compounds shown in general formula I, m of the first metal complex is the same as m of the second metal complex, and R of the first metal complex is 1 ~R 19 , R″ and R of the second metal complex 1 ~R 19 , R″ are the same, R′ of the first metal complex is different from R′ of the second metal complex, and R′ of the first metal complex and R′ of the second metal complex are each independently selected from hydrogen atom, C1 ~C 5 Straight-chain or branched alkyl, deuterated C 1 ~C 5 Straight or branched alkyl, C 5 ~C 10 alicyclic hydrocarbon groups, halogen atoms, substituted or unsubstituted C 6 ~C 12 The aryl group is preferably a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, a fluorine atom, a deuterated methyl group, a cyclohexyl group or a phenyl group.

[0056] As a more preferred embodiment of the present invention, the first metal complex and the second metal complex are both selected from the compounds shown in general formula I, m of the first metal complex is the same as m of the second metal complex, and R of the first metal complex is 1 ~R 19 , R′ and R of the second metal complex 1 ~R 19 , R' are the same, R" of the first metal complex is different from R" of the second metal complex, and R" of the first metal complex and R" of the second metal complex are each independently selected from hydrogen atom, C 1 ~C 5 Straight-chain or branched alkyl, deuterated C 1 ~C 5 Straight or branched alkyl, C 5 ~C 10 alicyclic hydrocarbon groups, halogen atoms, substituted or unsubstituted C 6 ~C 12 The aryl group is preferably a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, a fluorine atom, a deuterated methyl group, a cyclohexyl group or a phenyl group.

[0057] As a preferred embodiment of the present invention, the first metal complex and the second metal complex are both selected from the compounds represented by general formula II.

[0058] As a preferred embodiment of the present invention, the first metal complex and the second metal complex are both selected from the compounds represented by general formula II, and R′, R″, R 1 ~R 11 , R 20 ~R 26 and R′, R″, R 1 ~R 11 , R 20 ~R 26 At least one of is the same.

[0059] As a more preferred embodiment of the present invention, the first metal complex and the second metal complex are both selected from the compounds represented by general formula II, and R′, R″, R 1 ~R 11 and R′, R″, R 1 ~R 11 are the same, and R of the first metal complex 20 ~R 26 The second metal complex R 20 ~R 26 At least one of the first metal complex is the same, for example, R 20 ~R 26 The second metal complex R 20 ~R 26 Preferably, the first metal complex and the second metal complex are both selected from the compounds of general formula II, and R′, R″, R 1 ~R 11 and R′, R″, R 1 ~R 11 , R 23 are the same, and R of the first metal complex 20 ~R 22 With the second metal complex R 20 ~R 22 At least one of the first metal complex is the same as 24 ~R 26 R 24 ~R 26 At least one of the R 20 ~R 22 , R 24 ~R 26 are each independently selected from a hydrogen atom, a deuterium atom, a C 1 ~C 5 Straight-chain or branched alkyl, deuterated C 1 ~C 5 A straight chain or branched alkyl group and a halogen atom.

[0060] As a more preferred embodiment of the present invention, the first metal complex and the second metal complex are both selected from the compounds represented by general formula II, and R of the first metal complex 20 ~R 26 The second metal complex R 20 ~R 26are the same, and R′, R″, R 1 ~R 11 and R′, R″, R 1 ~R 11 At least one of the R′, R″, R 1 ~R 11 and R′, R″, R 1 ~R 11 Any one of them is the same, or any two are the same, or any three are the same, or any four are the same, or any five are the same, or any six are the same, or any seven are the same, or any eight are the same, or any nine are the same, or any ten are the same, or any eleven are the same, or any twelve are the same.

[0061] As a more preferred embodiment of the present invention, the first metal complex and the second metal complex are both selected from the compounds represented by general formula II, and R of the first metal complex 20 ~R 26 The second metal complex R 20 ~R 26 are the same, and R′, R″, R 1 ~R 11 and R′, R″, R 1 ~R 11 At least two are the same or at least three are the same or at least four are the same or at least five are the same or at least six are the same or at least seven are the same or at least eight are the same or at least nine are the same or at least ten are the same or at least eleven are the same or at least twelve are the same.

[0062] As a more preferred embodiment of the present invention, the first metal complex and the second metal complex are both selected from the compounds represented by general formula II, and R of the first metal complex 1 ~R 11 , R″, R 20 ~R 26 The second metal complex R 1 ~R 11 , R″, R 20 ~R 26 are the same, R′ of the first metal complex is different from R′ of the second metal complex, and R′ of the first metal complex and R′ of the second metal complex are each independently selected from a hydrogen atom, a C 1 ~C 5 Straight-chain or branched alkyl, deuterated C 1 ~C 5 Straight or branched alkyl, C 5~C 10 alicyclic hydrocarbon groups, halogen atoms, substituted or unsubstituted C 6 ~C 12 The aryl group is preferably a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, a fluorine atom, a deuterated methyl group, a cyclohexyl group or a phenyl group.

[0063] As a more preferred embodiment of the present invention, the first metal complex and the second metal complex are both selected from the compounds represented by general formula II, and R of the first metal complex 1 ~R 11 , R′, R 20 ~R 26 The second metal complex R 1 ~R 11 , R′, R 20 ~R 26 are the same, R″ of the first metal complex is different from R″ of the second metal complex, and R″ of the first metal complex and R″ of the second metal complex are each independently selected from a hydrogen atom, a C 1 ~C 5 Straight-chain or branched alkyl, deuterated C 1 ~C 5 Straight or branched alkyl, C 5 ~C 10 alicyclic hydrocarbon groups, halogen atoms, substituted or unsubstituted C 6 ~C 12 The aryl group is preferably a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, a fluorine atom, a deuterated methyl group, a cyclohexyl group or a phenyl group.

[0064] As a preferred embodiment of the present invention, the first metal complex and the second metal complex are both selected from the compounds represented by the general formula III. Preferably, R′, R″, R 1 ~R 11 and R, R″, R 1 ~R 11 At least one of the R′, R″, R 1 ~R 11 and R′, R″, R 1 ~R 11 Any one of them is the same, or any two are the same, or any three are the same, or any four are the same, or any five are the same, or any six are the same, or any seven are the same, or any eight are the same, or any nine are the same, or any ten are the same, or any eleven are the same, or any twelve are the same.

[0065] As a more preferred embodiment of the present invention, the first metal complex and the second metal complex are both selected from the compounds of formula III, and R' and R" of the first metal complex are the same as R' and R" of the second metal complex. 1 ~R 11 The second metal complex R 1 ~R 11 Any one of them is different, and the other 10 are the same, and R of the first metal complex 1 ~R 11 and the second metal complex R 1 ~R 11 are each independently selected from a hydrogen atom, a deuterium atom, a C 1 ~C 5 Straight-chain or branched alkyl, deuterated C 1 ~C 5 Straight or branched alkyl, C 5 ~C 12 alicyclic hydrocarbon groups, halogen atoms, substituted or unsubstituted C 6 ~C 12 Aryl, substituted or unsubstituted C 3 ~C 12 The heteroaryl group is preferably a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an adamantyl group, a cyclooctyl group, a deuterated methyl group, a deuterated ethyl group, a phenyl group, a fluorine atom and a bromine atom.

[0066] As a more preferred embodiment of the present invention, the first metal complex and the second metal complex are both selected from compounds represented by general formula III, and R of the first metal complex 1 ~R 11 , R″ and R of the second metal complex 1 ~R 11 , R″ are the same, R′ of the first metal complex is different from R′ of the second metal complex, and R′ of the first metal complex and R′ of the second metal complex are each independently selected from hydrogen atom, C 1 ~C 5 Straight-chain or branched alkyl, deuterated C 1 ~C 5 Straight or branched alkyl, C 5 ~C 10 alicyclic hydrocarbon groups, halogen atoms, substituted or unsubstituted C 6 ~C 12 The aryl group is preferably a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, a fluorine atom, a deuterated methyl group, a cyclohexyl group or a phenyl group.

[0067] As a more preferred embodiment of the present invention, the first metal complex and the second metal complex are both selected from compounds represented by general formula III, and R of the first metal complex 1 ~R 11 , R′ and R of the second metal complex 1 ~R 11 , R' are the same, R" of the first metal complex is different from R" of the second metal complex, and R" of the first metal complex and R" of the second metal complex are each independently selected from hydrogen atom, C 1 ~C 5 Straight-chain or branched alkyl, deuterated C 1 ~C 5 Straight or branched alkyl, C 5 ~C 10 alicyclic hydrocarbon groups, halogen atoms, substituted or unsubstituted C 6 ~C 12 The aryl group is preferably a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, a fluorine atom, a deuterated methyl group, a cyclohexyl group or a phenyl group.

[0068] In a second aspect, the present invention provides use of the luminescent material composition described in the first aspect in an organic electroluminescent device.

[0069] Preferably, the luminescent material composition is used as a luminescent material in a luminescent layer in an organic electroluminescent device.

[0070] In a third aspect, the present invention provides an OLED light-emitting layer, comprising the light-emitting material composition described in the first aspect of the present invention.

[0071] Preferably, the light-emitting layer comprises at least one host material, and the host material comprises at least one chemical group selected from the group consisting of: benzene, pyridine, pyrimidine, triazine, carbazole, azacarbazole, indolecarbazole, dibenzothiophene, azadibenzothiophene, dibenzofuran, azadibenzofuran, dibenzoselenophene, triphenylene, azatriphenylene, fluorene, silylate, naphthalene, quinoline, isoquinoline, quinazoline, quinoxaline, phenanthrene, azaphenanthrene and combinations thereof.

[0072] Preferably, the luminescent material composition is doped in the at least one host material.

[0073] Preferably, in the composition, the total weight of the first metal complex and the second metal complex accounts for 1% to 20%, preferably 1% to 10%, of the total weight of the light-emitting layer.

[0074] Preferably, in the composition, the weight ratio of the first metal complex to the second metal complex is between 1:99 and 99:1, for example, 1:0.02, 1:0.05, 1:0.08, 1:0.1, 1:0.2, 1:0.25, 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1:1, 1:1.1, 1:1.2, 1:1.3, 1:1.4, 1:1.5, 1:1.8, 1:1.9, 1:2, 1:3, 1:4, 1:5, 1:8, 1:10, 1:20, 1:30, 1:40, 1:50, 1:60, 1:70, 1:80, 1:90, 1:95.

[0075] Preferably, in the composition, the weight ratio of the first metal complex to the second metal complex is between 1:4 and 5:1, for example, 1:0.2, 1:0.5, 1:0.8, 1:1, 1:1.2, 1:1.5, 1:2, 1:3, 1:4.

[0076] In a fourth aspect, the present invention provides an organic electroluminescent device, comprising an anode layer, a cathode layer and the light-emitting layer described in the third aspect of the present invention.

[0077] The electroluminescent device comprises an anode, a cathode, and an organic layer disposed between the anode and the cathode. Preferably, the organic layer is a light-emitting layer, and the light-emitting layer comprises the light-emitting material composition described in the third aspect of the present invention.

[0078] Preferably, the organic electroluminescent device further comprises one or more of a hole injection layer, a hole transport layer, an electron blocking layer, a light emitting layer, a hole blocking layer, an electron transport layer and an electron injection layer.

[0079] Preferably, the difference in evaporation temperature between the first metal complex and the second metal complex during device preparation is less than 15°C, more preferably less than 5°C.

[0080] Preferably, the electroluminescent device emits green light or yellow light.

[0081] In a fifth aspect, the present invention provides a display device, comprising the electroluminescent device described in the fourth aspect of the present invention.

[0082] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention combines at least two different metal complexes with the same structural formula to prepare an electroluminescent device with lower voltage, higher efficiency and longer life, which can significantly improve the performance of the device. DETAILED DESCRIPTION

[0083] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with embodiments. The specific embodiments described herein are only used to explain the present invention and are not intended to constitute any limitation to the present invention. In addition, in the following description, the description of known structures and technologies is omitted to avoid unnecessary confusion of the concepts disclosed herein.

[0084] It should be noted that, unless otherwise defined, all technical and scientific terms used in the present invention have the same meanings as commonly used in the field to which the present invention belongs.

[0085] The present invention C 1 ~C 5 The straight chain or branched alkyl group can be methyl, ethyl, propyl (such as n-propyl, isopropyl), butyl (such as n-butyl, isobutyl, sec-butyl, tert-butyl), pentyl (such as n-pentyl, neopentyl) and the like.

[0086] The deuterated C 1 ~C 5 The straight-chain or branched alkyl group refers to an alkyl group in which some hydrogen atoms are substituted by deuterium, for example, it can be deuterated methyl, deuterated isopropyl, deuterated pentyl, deuterated neopentyl, deuterated butyl (such as deuterated n-butyl, deuterated isobutyl, deuterated sec-butyl, deuterated tert-butyl), etc.

[0087] The halogen atom mentioned in the present invention is a fluorine atom, a bromine atom or the like.

[0088] The alkoxy group of the present invention is C n H 2n+1 The group represented by O-, wherein n is 1 to 20.

[0089] The alkoxy group containing 1 to 5 C atoms in the present invention is C n H 2n+1 The group represented by O-, wherein n is 1 to 5. The alkoxy group containing 1 to 5 carbon atoms may be methoxy, ethoxy, or the like.

[0090] The alkylthio group of the present invention is C n H 2n+1 The group represented by S-, wherein n is 1 to 20.

[0091] The alkylamino group of the present invention refers to amino-NH 2 A group obtained by replacing one or two H in the group by an alkyl group.

[0092] The substituted phenyl group of the present invention includes phenyl substituted with an alkyl group, phenyl substituted with a deuterated alkyl group, phenyl substituted with a halogen atom, and the like.

[0093] The paracyclic structure of the present invention can be a benzo ring, a furan ring, a thienyl ring, etc. The paracyclic structure can be further substituted by a substituent, for example, substituted by a benzo group, substituted by an alkyl group, substituted by an alkyl group (such as a methyl-substituted benzo group, an ethyl-substituted benzo group, a propyl-substituted benzo group), substituted by a deuterated alkyl group (such as a deuterated methyl-substituted benzo group, a deuterated propyl-substituted benzo group), etc.

[0094] In the present invention, OLED can be manufactured on various substrates, such as glass, plastic and metal. OLED has multiple layers, including substrate, anode, hole injection layer, hole transport layer, electron blocking layer, light emitting layer, hole blocking layer, electron transport layer, electron injection layer and cathode. It can be manufactured by depositing the described layers in sequence. The properties and functions of each layer and exemplary materials are described in more detail in columns 6-10 of U.S. Patent US7,279,704B2, the entire contents of which are incorporated herein by reference.

[0095] There are more examples of each of these layers. For example, a flexible and transparent substrate-anode combination is disclosed in U.S. Pat. No. 5,844,363, which is incorporated by reference in its entirety. An example of a p-doped hole transport layer is one doped with F at a molar ratio of 50:1. 4

[0013] An example of an n-doped electron transport layer is BPhen doped with Li at a 1:1 molar ratio, as disclosed in U.S. Patent Application Publication No. 2003 / 0230980, which is incorporated by reference in its entirety.

[0013] An example of an n-doped electron transport layer is BPhen doped with Li at a 1:1 molar ratio, as disclosed in U.S. Patent Application Publication No. 2003 / 0230980, which is incorporated by reference in its entirety.

[0013] U.S. Patent Nos. 5,703,436 and 5,707,745, which are incorporated by reference in their entirety, disclose examples of cathodes including composite cathodes having a thin layer of a metal such as Mg:Ag and an overlying transparent, conductive, sputter-deposited ITO layer. The principles and use of barrier layers are described in more detail in U.S. Patent No. 6,097,147 and U.S. Patent Application Publication No. 2003 / 0230980, which are incorporated by reference in their entirety. Examples of injection layers are provided in U.S. Patent Application Publication No. 2004 / 0174H6, which is incorporated by reference in its entirety. A description of protective layers can be found in U.S. Patent Application Publication No. 2004 / 0174H6, which is incorporated by reference in its entirety.

[0096] The functions of an OLED can be achieved by combining the various layers described above, or some layers can be omitted completely. It can also include other layers that are not explicitly described. Within each layer, a single material or a mixture of multiple materials can be used to achieve optimal performance. Any functional layer can include several sublayers. For example, a light-emitting layer can have two layers of different light-emitting materials to achieve a desired light-emitting spectrum.

[0097] Devices manufactured according to embodiments of the present invention can be incorporated into various consumer products having one or more electronic component modules (or units) of the device. Some examples of these consumer products include flat panel displays, monitors, medical monitors, televisions, billboards, lights for indoor or outdoor lighting and / or signaling, heads-up displays, fully or partially transparent displays, flexible displays, smart phones, tablet computers, tablet phones, wearable devices, smart watches, laptop computers, digital cameras, camcorders, viewfinders, micro displays, 3-D displays, vehicle displays, and taillights.

[0098] The materials and structures described herein may also be used in other organic electronic devices listed above.

[0099] As used herein, "top" means farthest from the substrate, while "bottom" means closest to the substrate. Where a first layer is described as being "disposed" "on" a second layer, the first layer is disposed farther from the substrate. Unless it is specified that the first layer is "in contact with" the second layer, other layers may be present between the first and second layers. For example, a cathode may be described as being "disposed" "on" an anode even though various organic layers are present between the cathode and the anode.

[0100] As used herein, "solution processable" means capable of being dissolved, dispersed or transported in and / or deposited from a liquid medium in the form of a solution or suspension.

[0101] When the ligand is believed to directly contribute to the photosensitive property of the emissive material, the ligand may be referred to as "photosensitive". When the ligand is not believed to contribute to the photosensitive property of the emissive material, the ligand may be referred to as "ancillary", but the ancillary ligand may modify the properties of the photosensitive ligand.

[0102] It is believed that the internal quantum efficiency (IQE) of fluorescent OLEDs can exceed the 25% spin-statistical limit through delayed fluorescence. Delayed fluorescence can generally be divided into two types, namely p-type delayed fluorescence and E-type delayed fluorescence. P-type delayed fluorescence is generated by triplet-triplet annihilation (TTA).

[0103] On the other hand, E-type delayed fluorescence does not rely on the collision of two triplets, but on the conversion between triplet and singlet excited state. Compounds capable of producing E-type delayed fluorescence need to have a very small single-triplet gap for the conversion between energy states. Thermal energy can activate the transition from triplet back to singlet. This type of delayed fluorescence is also called thermally activated delayed fluorescence (TADF). The notable feature of TADF is that the delayed component increases with increasing temperature. If the reverse intersystem crossing (RISC) rate is fast enough to minimize the non-radiative decay by triplet, the fraction of backfilling singlet excited state may reach 75%. The total singlet fraction can be 100%, far exceeding the 25% of the spin statistics of the excitons generated by electricity.

[0104] The E-type delayed fluorescence feature can be seen in an exciplex system or a single compound. Without being bound by theory, it is believed that the E-type delayed fluorescence requires the luminescent material to have a small singlet-triplet energy gap (ΔE S-T ). Organic non-metal-containing donor-acceptor luminescent materials may be able to achieve this. The emission of these materials is usually characterized by donor-acceptor charge transfer (CT) type emission. The spatial separation of the HOMO and LUMO in these donor-acceptor type compounds usually produces a small ΔE S-T These states may include CT states. Generally, donor-acceptor light-emitting materials are constructed by linking an electron donor moiety (eg, an amino group or a carbazole derivative) to an electron acceptor moiety (eg, a six-membered aromatic ring containing N).

[0105] The specific materials used in the organic light-emitting devices described in the present invention can be used in combination with various other materials present in the device. The combination of these materials is described in detail in paragraphs 0132-0161 of U.S. Patent Application US2016 / 0359122A1, the entire contents of which are incorporated herein by reference. The materials described or mentioned therein are non-limiting examples of materials that can be used in combination with the compounds disclosed herein, and those skilled in the art can easily consult the literature to identify other materials that can be used in combination.

[0106] The materials described herein as specific layers that can be used in organic light-emitting devices can be used in combination with a variety of other materials present in the device. For example, the compounds disclosed herein can be used in combination with a variety of hosts, transport layers, barrier layers, injection layers, electrodes, and other layers that may be present. The combination of these materials is described in detail in paragraphs 0080-0101 of U.S. Patent Application US2015 / 0349273A1, the entire contents of which are incorporated herein by reference. The materials described or mentioned therein are non-limiting examples of materials that can be used in combination with the compounds disclosed herein, and those skilled in the art can easily consult the literature to identify other materials that can be used in combination.

[0107] In the embodiment of material synthesis, unless otherwise stated, all reactions are carried out under nitrogen protection. All reaction solvents are anhydrous and used as they are from commercial sources. The synthetic product uses one or more conventional equipment in the art (including but not limited to Agilent's liquid chromatograph, liquid chromatography-mass spectrometer, gas chromatography-mass spectrometer, differential scanning calorimeter, fluorescence spectrophotometer, electrochemical workstation, sublimator, etc.), and the structure is confirmed and the characteristics are tested by methods well known to those skilled in the art. In the embodiment of the device, the characteristics of the device are also tested by methods well known to those skilled in the art using conventional equipment in the art (including but not limited to the evaporation machine produced by Nanjing Institute of Micro-Science, the optical test system and life test system produced by Suzhou Fushida, the ellipsometer produced by Wuhan Yiguang Technology, etc.). Since those skilled in the art are aware of the relevant contents such as the use of the above-mentioned equipment and the test method, the inherent data of the sample can be obtained with certainty and without being affected, so the above-mentioned relevant contents will not be elaborated in this patent.

[0108] Material synthesis:

[0109] The preparation methods of the first metal complex and the second metal complex selected in the present invention are not limited. The following compounds are typically but not limitedly exemplified, and their synthesis routes and preparation methods are as follows:

[0110] Synthesis Example 1: Synthesis of Compound II-1

[0111]

[0112] The reaction formula is as follows:

[0113]

[0114] The specific experimental steps are:

[0115] (1) In a 500 mL three-necked flask equipped with a mechanical stirrer, a reflux condenser and a nitrogen protection device, add ligand P1 (25 mmol, 7.76 g), hydrated iridium trichloride (10 mmol, 3.35 g), 90 mL of ethylene glycol monoethyl ether and 30 mL of distilled water in sequence. Evacuate the flask and fill it with N 2 , repeat 5 times to remove oxygen from the system. Heat to 110℃ and reflux for 24 hours. After natural cooling, add 10mL of distilled water, shake, filter, wash with water, and wash with ethanol. Vacuum dry to obtain 7.51g of crude dichlorobridged intermediate M6 as a yellow solid with a yield of 71%.

[0116] (2) In a 250 ml three-necked flask equipped with a magnetic stirrer and a reflux condenser, the intermediate M6 (5 mmol, 8.46 g), acetylacetone (25 mmol, 2.5 g, 2.6 mL), anhydrous Na2 CO 3 (22mmol, 2.35g) and 100mL of ethylene glycol monoethyl ether. Vacuum and fill with N 2 , repeat 5 times to remove oxygen from the system. 2 Heat under reflux at 120°C oil bath for 24 hours under protection. Cool naturally to room temperature, filter, wash with water, n-hexane, and ether in sequence, and dry to obtain a yellow crude product. 2 Cl 2 Dissolve and separate on column, eluent CH 2 Cl 2 After washing and drying the solvent, 7.55 g of yellow powder was obtained with a yield of 83%.

[0117] Product MS (m / e): 910.29; Elemental analysis (C 49 H 41 Ir 4 O 2 ): Theoretical value C: 64.67%, H: 4.54%, N: 6.16%; Measured value C: 65.35%, H: 4.62%, N: 6.07%.

[0118] Synthesis Example 2: Synthesis of Compound II-2

[0119]

[0120] Substituting acetylacetone with 2,2,6,6-tetramethylheptane-3,5-dione, and the other raw materials and steps were the same as those in Synthesis Example 1, compound II-2 was obtained.

[0121] Product MS (m / e): 994.48; Elemental analysis (C 55 H 53 Ir 4 O 2 ): Theoretical value C: 66.44%, H: 5.37%, N: 5.64%; Measured value C: 66.52%, H: 5.31%, N: 5.59%.

[0122] Synthesis Example 3: Synthesis of Compound II-3

[0123]

[0124] Using 3,7-diethylnonane-4,6-dione instead of acetylacetone, the other raw materials and steps are the same as those in Synthesis Example 1 to obtain compound II-3.

[0125] Product MS (m / e): 1022.53; Elemental analysis (C 57 H 57 Ir 4 O2 ): Theoretical value C: 66.97%, H: 5.62%, N: 5.48%; Measured value C: 66.92%, H: 5.66%, N: 5.45%.

[0126] Synthesis Example 4: Synthesis of Compound III-1

[0127]

[0128] The reaction formula is as follows:

[0129]

[0130] The specific experimental steps are as follows: In a 250ml three-necked flask equipped with a magnetic stirrer and a reflux condenser, add Ir(acac) 3 (10 mmol, 4.9 g), ligand P1 (40 mmol, 12.42 g), 150 mL of glycerol. Vacuum and fill with N 2 , repeat 5 times to remove oxygen from the system. 2 Heat under reflux at 190℃ oil bath for 24 hours under protection. Cool naturally to room temperature, filter, wash with water, n-hexane and ether in sequence, and dry to obtain a yellow crude product. 2 Cl 2 Dissolve and separate on column, eluent CH 2 Cl 2 After washing and drying the solvent, 6.12 g of yellow powder was obtained with a yield of 41%.

[0131] Product MS (m / e): 1119.37; Elemental analysis (C 66 H 50 Ir 6 ): Theoretical value C: 70.82%, H: 4.5%, N: 7.51%; Measured value C: 70.93%, H: 4.62%, N: 7.44%.

[0132] Synthesis Example 5: Synthesis of Compound I-46

[0133]

[0134] The reaction formula is as follows:

[0135]

[0136] The specific experimental steps are:

[0137] (1) In a 100 mL three-necked flask equipped with a mechanical stirrer, a reflux condenser and a nitrogen protection device, add phenylpyridine (15 mmol, 2.5 mL), iridium trichloride hydrate (6 mmol, 2.01 g), ethylene glycol monoethyl ether 45 mL and distilled water 15 mL in sequence. Evacuate the flask and fill it with N 2 , repeat five times to remove oxygen from the system. Heat to 110℃ and reflux for 24 hours. After natural cooling, add 10mL of distilled water, shake, filter, wash with water, and wash with ethanol. Vacuum dry to obtain 2.6g of crude dichlorobridged intermediate M7 as a yellow solid with a yield of 81.0%.

[0138] (2) In a 500 mL three-necked flask equipped with a nitrogen protection device, add the dichloro bridged intermediate M7 (10.7 g, 10 mmol) and 150 ml of dichloromethane in sequence, stir well, then add a 200 ml methanol solution of silver trifluoromethanesulfonate (6.4 g, 25 mmol), stir for 24 hours under light-proof conditions, cool to room temperature, filter out the generated AgCl with diatomaceous earth, and spin dry the filtrate to obtain a yellowish brown solid powder. This solid is used directly in the next step without treatment.

[0139] (3) In a 250 ml three-necked flask, add the khaki solid (5.1 g, 6.9 mmol) obtained in step (2) and ligand P1 (6.5 g, 21 mmol), then add 100 ml of ethanol, heat the mixture under reflux for 36 hours, cool the reactants to room temperature, filter the generated yellow solid, dissolve the solid in dichloromethane, and separate by column chromatography to obtain 3.58 g of a yellow solid with a yield of 64%.

[0140] Product MS (m / e): 810.23; Elemental analysis (C 41 H 27 Ir 4 O): Theoretical value C: 65.25%, H: 4.11%, N: 6.92%; Measured value C: 65.19%, H: 4.14%, N: 6.98%.

[0141] Other compounds such as compound III-2 and I-48 were prepared and synthesized with reference to patent CN112321647B.

[0142] Those skilled in the art should be aware that the above preparation method is only an illustrative example, and those skilled in the art can obtain other compound structures of the present invention by improving it.

[0143] The method for making the electroluminescent device is not particularly limited. The preparation method of the following embodiment is only an example and should not be construed as limiting. A person skilled in the art can reasonably improve the preparation method of the following embodiment based on the prior art. For example, the ratio of various materials in the light-emitting layer is not particularly limited, and a person skilled in the art can reasonably select within a certain range based on the prior art. For example, based on the total weight of the light-emitting layer material, the main material accounts for 80% to 99%, and the first metal complex and the second metal complex account for 1% to 20% or preferably 1% to 10%.

[0144] Device Example 1

[0145] First, the glass substrate with a 120nm thick indium tin oxide (ITO) anode was cleaned and then treated with UV ozone and oxygen plasma. After treatment, the substrate was dried in a nitrogen-filled glove box to remove moisture, and then the substrate was mounted on a substrate holder and loaded into a vacuum chamber. The organic layers specified below were placed in a vacuum of approximately 10 -8 Torr's case The ITO anode was deposited sequentially by thermal vacuum deposition at a rate of . At the same time, the deposited compounds HT and NDP-9 were used as hole injection layers (HIL) with a thickness of Compound HT was used as a hole transport layer (HTL) with a thickness of The compound TAPC is used as an electron blocking layer (EBL) with a thickness of Then, DIC-TRZ as the host compound and compound II-1 as the first dopant and compound II-2 as the second dopant were co-evaporated to form an emitting layer (EML) with a thickness of The compound DIC-TRZ accounts for 94% of the total weight of the light-emitting layer, the compound II-1 accounts for 3% of the total weight of the light-emitting layer, and the compound II-2 accounts for 3% of the total weight of the light-emitting layer. The compound TPBI is used as the hole blocking layer (HBL) with a thickness of On the hole blocking layer, compound ET01 and 8-hydroxyquinoline-lithium (Liq) were co-evaporated as an electron transport layer (ETL) with a thickness of The compound ET01 and Liq each account for 50% of the total weight of the electron transport layer. LiF with a thickness of 1000 mm was used as an electron injection layer (EIL), and the The device was then transferred back to the glove box and encapsulated with a glass lid to complete the device.

[0146] Device Example 2

[0147] The implementation method of Device Example 2 is the same as that of Device Example 1, except that the weight of Compound II-2 in the light emitting layer (EML) is changed from 3% to 6% and the weight of the host material is changed to 91%.

[0148] Device Example 3

[0149] The implementation method of device example 3 is the same as that of device example 1, except that in the light emitting layer (EML), the total weight of compound II-1 is changed from 3% to 1%, the total weight of compound II-2 is changed from 3% to 4%, and the weight of the host material is changed to 95%.

[0150] Device Example 4

[0151] The implementation method of Device Example 4 is the same as that of Device Example 1, except that Compound II-3 is used instead of Compound II-2 as the second dopant in the emission layer (EML).

[0152] Device Example 5

[0153] The implementation method of Device Example 5 is the same as that of Device Example 1, except that Compound II-3 is used instead of Compound II-1 as the first dopant in the light emitting layer (EML).

[0154] Device Example 6

[0155] The implementation method of Device Example 6 is the same as that of Device Example 1, except that Compound III-1 is used instead of Compound II-1 as the first dopant, and Compound III-2 is used instead of Compound II-2 as the second dopant in the light emitting layer (EML).

[0156] Device Example 7

[0157] The implementation method of Device Example 7 is the same as that of Device Example 1 except that Compound I-46 is used instead of Compound II-1 as the first dopant, and Compound I-48 is used instead of Compound II-2 as the second dopant in the emission layer (EML).

[0158] Device Example 8

[0159] The implementation method of Device Example 8 is the same as that of Device Example 1, except that Compound III-1 is used as the second dopant in the light emitting layer (EML) instead of Compound II-2.

[0160] Device Example 9

[0161] The implementation method of Device Example 9 is the same as that of Device Example 1, except that Compound I-46 is used as the second dopant in the emission layer (EML) instead of Compound II-2.

[0162] Device Comparison Example 1

[0163] The implementation of Comparative Device Example 1 is the same as that of Example 1, except that the first and second dopants are replaced with Compound II-1 in the light emitting layer (EML).

[0164] Device Comparison Example 2

[0165] The implementation of Comparative Device Example 2 is the same as that of Example Device 2, except that the first and second dopants are replaced with Compound III-1 in the light emitting layer (EML).

[0166] Device Comparison Example 3

[0167] The implementation of Comparative Device Example 3 is the same as that of Example Device 3, except that Compound I-46 is used instead of the first and second dopants in the emission layer (EML).

[0168] The detailed device layer structures and thicknesses are shown in Table 1. For layers using more than one material, different compounds are doped in the stated weight ratios.

[0169] Table 1 Device structures of device embodiments and comparative examples

[0170]

[0171]

[0172]

[0173] The material structure used in the device is shown below:

[0174]

[0175] Table 2 lists the 2 Under the above conditions, the voltage, current efficiency and device life of device embodiments 1-9 and device comparative examples 1-3 were measured.

[0176] Table 2 Device data

[0177]

[0178]

[0179] in conclusion:

[0180] Through the device data, we can find that compared with the device data of Examples 1, 4 to 9 using the combination of the present invention and Comparative Examples 1 to 3, whether it is voltage, current efficiency or life, using two metal complexes as dopants is better than using a single metal complex as a dopant, which brings unexpected effects to device performance.

[0181] It can be seen from the device data of Examples 1 to 3 that by changing the ratio of the two dopants to the total weight of the light-emitting layer, the device data obtained is also different. When the doping ratio of compound II-1 and compound II-2 is 1:1, the device voltage is the smallest, the current efficiency is the largest, and the life is the longest.

[0182] From the device data of Examples 1 and 4-7 compared with Examples 8-9, it can be seen that when using dual dopants, the more similar the structures of the two compounds are, the better the performance of the prepared devices is, especially Examples 6 and 7, whose current efficiency is significantly improved and the lifespan is unexpectedly improved.

[0183] In summary, the combination of the first metal complex and the second metal complex disclosed in the present invention can exhibit excellent comprehensive device performance in the device, such as lower driving voltage, higher efficiency and ultra-long device life, because the two types of compounds can match each other well in energy.

[0184] It should be understood that the various embodiments described herein are only examples and are not intended to limit the scope of the present invention. Therefore, as will be apparent to those skilled in the art, the claimed invention may include variations of the specific embodiments and preferred embodiments described herein. Many of the materials and structures described herein may be replaced with other materials and structures without departing from the spirit of the present invention. It should be understood that the various theories about why the present invention works are not intended to be restrictive.

Claims

1. A luminescent material composition, comprising a first metal complex and a second metal complex, wherein the first metal complex and the second metal complex are different from each other, and the first metal complex and the second metal complex are each independently selected from the compound represented by formula (I-1) or formula (I-2) or formula (I-3), in, R1~R 11 are independently selected from a hydrogen atom, a deuterium atom, a C1-C5 straight chain or branched alkyl group, a deuterated C1-C5 straight chain or branched alkyl group, and a halogen atom; R' and R" are independently selected from hydrogen atom, C1-C5 straight chain or branched alkyl group, deuterated C1-C5 straight chain or branched alkyl group, halogen atom; R 12 ~R 19 are independently selected from a hydrogen atom, a deuterium atom, a C1-C5 straight chain or branched alkyl group, a deuterated C1-C5 straight chain or branched alkyl group, and a halogen atom; R 20 ~R 26 Each of the following is independently selected from a hydrogen atom, a deuterium atom, a C1-C5 straight chain or branched alkyl group, and a deuterated C1-C5 straight chain or branched alkyl group; m is 1; The weight ratio of the first metal complex to the second metal complex is 1:(0.5-2).

2. The composition according to claim 1, characterized in that The R' and R" are independently selected from C1-C5 straight chain or branched alkyl, deuterated C1-C5 straight chain or branched alkyl.

3. The composition according to claim 1, characterized in that The R' and R" are independently selected from methyl, ethyl, n-propyl, isopropyl or deuterated methyl.

4. The composition according to claim 1, characterized in that R1~R 11 Each of them is independently selected from a hydrogen atom, a deuterium atom, a C1-C5 straight chain or branched alkyl group, and a deuterated C1-C5 straight chain or branched alkyl group.

5. The composition according to claim 1, characterized in that R1~R 11 Each of the above groups is independently selected from a hydrogen atom, a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a deuterated methyl group and a deuterated ethyl group.

6. The composition according to claim 1, characterized in that R 12 ~R 19 Each of them is independently selected from a hydrogen atom, a deuterium atom, a C1-C5 straight chain or branched alkyl group, and a deuterated C1-C5 straight chain or branched alkyl group.

7. The composition according to claim 1, characterized in that The R 12 ~R 19 are independently selected from the group consisting of hydrogen, fluorine, methyl, ethyl, isopropyl, n-propyl, n-butyl, tert-butyl, sec-butyl, isobutyl and deuterated methyl; and / or R 20 ~R 26 Each of them is independently selected from a hydrogen atom, a C1-C5 straight-chain or branched alkyl group.

8. The composition according to claim 7, characterized in that R 20 ~R 26 They are each independently arbitrarily selected from a hydrogen atom, a methyl group and an ethyl group.

9. The composition according to claim 1, characterized in that Said Selected from the following groups: and / or, Said Selected from the following groups:

10. A luminescent material composition, comprising a first metal complex and a second metal complex, wherein the first metal complex and the second metal complex are different from each other, and the first metal complex and the second metal complex are selected from the following structures: in, The weight ratio of the first metal complex to the second metal complex is 1:(0.5-2).

11. The composition according to any one of claims 1 to 9, characterized in that The first metal complex and the second metal complex are both selected from the compound represented by formula (I-1).

12. The composition according to claim 11, characterized in that The groups R', R", R1-R 19 and the groups R', R", R1-R 19 At least one of is the same.

13. The composition according to any one of claims 1 to 9, characterized in that The first metal complex and the second metal complex are both selected from the compound represented by formula (I-2).

14. The composition according to claim 13, characterized in that The groups R', R", R1-R 11 , R 20 ~R 26 and the groups R', R", R1-R 11 , R 20 ~R 26 At least one of is the same.

15. The composition according to any one of claims 1 to 9, characterized in that The first metal complex and the second metal complex are both selected from the compound represented by formula (I-3).

16. The composition according to claim 15, characterized in that The groups R', R", R1-R 11 and the groups R, R″, R1 to R 11 At least one of is the same.

17. The composition according to any one of claims 1 to 10, characterized in that The weight ratio of the first metal complex to the second metal complex is 1:(0.8-1.3).

18. Use of the composition according to any one of claims 1 to 17 in the preparation of an organic electroluminescent device, wherein: The composition is used as a light-emitting material in a light-emitting layer in an organic electroluminescent device.

19. An OLED light-emitting layer, comprising the composition according to any one of claims 1 to 17, wherein: The sum of the weights of the first metal complex and the second metal complex in the composition accounts for 1% to 10% of the total weight of the light-emitting layer.

20. An organic electroluminescent device comprising an anode layer, a cathode layer and the light-emitting layer according to claim 19.

21. The device according to claim 20, characterized in that The organic electroluminescent device further comprises one or more of a hole injection layer, a hole transport layer, an electron blocking layer, a light emitting layer, a hole blocking layer, an electron transport layer, and an electron injection layer.

22. A display device comprising the organic electroluminescent device according to claim 20 or 21.

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