Patent Application
20240206332
The present disclosure relates to an organic light emitting device having improved driving voltage, efficiency, and lifespan.
In general, an organic light emitting phenomenon refers to a phenomenon where electric energy is converted into light energy by using an organic material. The organic light emitting device using the organic light emitting phenomenon has characteristics such as a wide viewing angle, an excellent contrast, a fast response time, an excellent luminance, driving voltage and response speed, and thus many studies have proceeded.
The organic light emitting device generally has a structure which comprises an anode, a cathode, and an organic material layer interposed between the anode and the cathode. The organic material layer frequently has a multilayered structure that comprises different materials in order to enhance efficiency and stability of the organic light emitting device, and for example, the organic material layer can be formed of a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer, and the like. In the structure of the organic light emitting device, if a voltage is applied between two electrodes, the holes are injected from an anode into the organic material layer and the electrons are injected from the cathode into the organic material layer, and when the injected holes and electrons meet each other, an exciton is formed, and light is emitted when the exciton falls to a ground state again.
There is a continuing need for the development of an organic light emitting device having improved driving voltage, efficiency, and lifespan.
(Patent Literature 0001) Korean Unexamined Patent Publication No. 10-2000-0051826
The present disclosure relates to an organic light emitting device having improved driving voltage, efficiency, and lifespan.
In the present disclosure, provided is an organic light emitting device including
The above-described organic light emitting device includes the compound of Chemical Formula 1 and the compound of Chemical Formula 2 in the light emitting layer, and thus can have improved efficiency, low driving voltage, and/or lifespan.
Hereinafter, embodiments of the present disclosure will be described in more detail to facilitate understanding of the invention.
As used herein, the notation ,
or means a bond linked to another substituent group.
As used herein, the term “substituted or unsubstituted” means being unsubstituted or substituted with one or more substituents selected from the group consisting of deuterium, a halogen group, a nitrile group, a nitro group, a hydroxyl group, a carbonyl group, an ester group, an imide group, an amino group, a phosphine oxide group, an alkoxy group, an aryloxy group, an alkylthioxy group, an arylthioxy group, an alkylsulfoxy group, an arylsulfoxy group, a silyl group, a boron group, an alkyl group, a cycloalkyl group, an alkenyl group, an aryl group, an aralkyl group, an aralkenyl group, an alkylaryl group, an alkylamine group, an aralkylamine group, a heteroarylamine group, an arylamine group, an arylphosphine group, and a heterocyclic group containing at least one of N, O and S atoms, or being unsubstituted or substituted with a substituent in which two or more substituents of the above-exemplified substituents are connected. For example, “a substituent in which two or more substituents are connected” can be a biphenyl group. Namely, a biphenyl group can be an aryl group, or it can also be interpreted as a substituent in which two phenyl groups are connected.
In the present disclosure, the carbon number of a carbonyl group is not particularly limited, but is preferably 1 to 40. Specifically, the carbonyl group can be a substituent having the following structural formulae, but is not limited thereto:
In the present disclosure, an ester group can have a structure in which oxygen of the ester group is substituted by a straight-chain, branched-chain, or cyclic alkyl group having 1 to 25 carbon atoms, or an aryl group having 6 to 25 carbon atoms. Specifically, the ester group can be a substituent having the following structural formulae, but is not limited thereto:
In the present disclosure, the carbon number of an imide group is not particularly limited, but is preferably 1 to 25. Specifically, the imide group can be a substituent having the following structural formulae, but is not limited thereto:
In the present disclosure, a silyl group specifically includes a trimethylsilyl group, a triethylsilyl group, a t-butyldimethylsilyl group, a vinyldimethylsilyl group, a propyldimethylsilyl group, a triphenylsilyl group, a diphenylsilyl group, a phenylsilyl group and the like, but is not limited thereto.
In the present disclosure, a boron group specifically includes a trimethylboron group, a triethylboron group, a t-butyldimethylboron group, a triphenylboron group, a phenylboron group and the like, but is not limited thereto.
In the present disclosure, examples of a halogen group include fluorine, chlorine, bromine, or iodine.
In the present disclosure, the alkyl group can be straight-chain, or branched-chain, and the carbon number thereof is not particularly limited, but is preferably 1 to 40. According to one embodiment, the carbon number of the alkyl group is 1 to 20. According to another embodiment, the carbon number of the alkyl group is 1 to 10. According to another embodiment, the carbon number of the alkyl group is 1 to 6. Specific examples of the alkyl group include methyl, ethyl, propyl, n-propyl, isopropyl, butyl, n-butyl, isobutyl, tert-butyl, sec-butyl, 1-methyl-butyl, 1-ethyl-butyl, pentyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, hexyl, n-hexyl, 1-methylpentyl, 2-methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl, 2-ethylbutyl, heptyl, n-heptyl, 1-methylhexyl, cyclopentylmethyl, cyclohexylmethyl, octyl, n-octyl, tert-octyl, 1-methylheptyl, 2-ethylhexyl, 2-propylpentyl, n-nonyl, 2,2-dimethylheptyl, 1-ethyl-propyl, 1,1-dimethyl-propyl, isohexyl, 4-methylhexyl, 5-methylhexyl, and the like, but are not limited thereto.
In the present disclosure, the alkenyl group can be straight-chain or branched-chain, and the carbon number thereof is not particularly limited, but is preferably 2 to 40. According to one embodiment, the carbon number of the alkenyl group is 2 to 20. According to another embodiment, the carbon number of the alkenyl group is 2 to 10. According to another embodiment, the carbon number of the alkenyl group is 2 to 6. Specific examples thereof include vinyl, 1-propenyl, isopropenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-pentenyl, 2-pentenyl, 3-pentenyl, 3-methyl-1-butenyl, 1,3-butadienyl, allyl, 1-phenylvinyl-1-yl, 2-phenylvinyl-1-yl, 2,2-diphenylvinyl-1-yl, 2-phenyl-2-(naphthyl-1-yl)vinyl-1-yl, 2,2-bis(diphenyl-1-yl)vinyl-1-yl, a stilbenyl group, a styrenyl group, and the like, but are not limited thereto.
In the present disclosure, a cycloalkyl group is not particularly limited, but the carbon number thereof is preferably 3 to 60. According to one embodiment, the carbon number of the cycloalkyl group is 3 to 30. According to another embodiment, the carbon number of the cycloalkyl group is 3 to 20. According to another embodiment, the carbon number of the cycloalkyl group is 3 to 6. Specific examples thereof include cyclopropyl, cyclobutyl, cyclopentyl, 3-methylcyclopentyl, 2,3-dimethylcyclopentyl, cyclohexyl, 3-methylcyclohexyl, 4-methylcyclohexyl, 2,3-dimethylcyclohexyl, 3,4,5-trimethylcyclohexyl, 4-tert-butylcyclohexyl, cycloheptyl, cyclooctyl, and the like, but are not limited thereto.
In the present disclosure, an aryl group is not particularly limited, but the carbon number thereof is preferably 6 to 60, and it can be a monocyclic aryl group or a polycyclic aryl group. According to one embodiment, the carbon number of the aryl group is 6 to 30. According to one embodiment, the carbon number of the aryl group is 6 to 20. The monocyclic aryl group includes a phenyl group, a biphenyl group, a terphenyl group and the like, but is not limited thereto. The polycyclic aryl group includes a naphthyl group, an anthracenyl group, a phenanthryl group, a pyrenyl group, a perylenyl group, a chrysenyl group, a fluorenyl group or the like, but is not limited thereto.
In the present disclosure, a fluorenyl group can be substituted, and two substituents can be bonded to each other to form a spiro structure. In the case where the fluorenyl group is substituted,
and the like can be formed. However, the structure is not limited thereto.
In the present disclosure, a heterocyclic group is a heterocyclic group containing at least one heteroatom of O, N, Si and S as a heterogeneous element, and the carbon number thereof is not particularly limited, but is preferably 2 to 60. Examples of the heterocyclic group include a thiophene group, a furan group, a pyrrole group, an imidazole group, a thiazole group, an oxazol group, an oxadiazol group, a triazol group, a pyridyl group, a bipyridyl group, a pyrimidyl group, a triazine group, an acridyl group, a pyridazine group, a pyrazinyl group, a quinolinyl group, a quinazoline group, a quinoxalinyl group, a phthalazinyl group, a pyridopyrimidinyl group, a pyridopyrazinyl group, a pyrazinopyrazinyl group, an isoquinoline group, an indole group, a carbazole group, a benzoxazole group, a benzoimidazole group, a benzothiazol group, a benzocarbazole group, a benzothiophene group, a dibenzothiophene group, a benzofuranyl group, a phenanthroline group, an isoxazolyl group, a thiadiazolyl group, a phenothiazinyl group, a dibenzofuranyl group, and the like, but are not limited thereto.
In the present disclosure, the aryl group in the aralkyl group, the aralkenyl group, the alkylaryl group, and the arylamine group is the same as the aforementioned examples of the aryl group. In the present disclosure, the alkyl group in the aralkyl group, the alkylaryl group and the alkylamine group is the same as the aforementioned examples of the alkyl group. In the present disclosure, the heteroaryl in the heteroarylamine can apply the aforementioned description of the heterocyclic group. In the present disclosure, the alkenyl group in the aralkenyl group is the same as the aforementioned examples of the alkenyl group. In the present disclosure, the aforementioned description of the aryl group can be applied except that the arylene is a divalent group. In the present disclosure, the aforementioned description of the heterocyclic group can be applied except that the heteroarylene is a divalent group. In the present disclosure, the aforementioned description of the aryl group or cycloalkyl group can be applied except that the hydrocarbon ring is not a monovalent group but formed by combining two substituent groups. In the present disclosure, the aforementioned description of the heterocyclic group can be applied, except that the heterocycle is not a monovalent group but formed by combining two substituent groups.
The present disclosure will be described in detail for each configuration.
Anode and Cathode
The anode and cathode used in the present disclosure refer to electrodes used in an organic light emitting device.
As the anode material, generally, a material having a large work function is preferably used so that holes can be smoothly injected into the organic material layer. Specific examples of the anode material include metals such as vanadium, chrome, copper, zinc, and gold, or an alloy thereof; metal oxides such as zinc oxides, indium oxides, indium tin oxides (ITO), and indium zinc oxides (IZO); a combination of metals and oxides such as ZnO:Al or SnO2:Sb; conductive polymers such as poly(3-methylthiophene), poly[3,4-(ethylene-1,2-dioxy)thiophene](PEDOT), polypyrrole, and polyaniline, and the like, but are not limited thereto.
As the cathode material, generally, a material having a small work function is preferably used so that electrons can be easily injected into the organic material layer. Specific examples of the cathode material include metals such as magnesium, calcium, sodium, potassium, titanium, indium, yttrium, lithium, gadolinium, aluminum, silver, tin, and lead, or an alloy thereof; a multilayered structure material such as LiF/Al or LiO2/Al, and the like, but are not limited thereto.
Hole Injection Layer
The organic light emitting device according to the present disclosure can further include a hole injection layer on the anode, if necessary.
The hole injection layer is a layer for injecting holes from the electrode, and the hole injection material is preferably a compound which can transport the holes, thus has a hole-injecting effect in the anode and an excellent hole-injecting effect to the light emitting layer or the light emitting material, prevents excitons produced in the light emitting layer from moving to an electron injection layer or the electron injection material, and is excellent in the ability to form a thin film. It is preferable that a HOMO (highest occupied molecular orbital) of the hole injection material is between the work function of the anode material and a HOMO of a peripheral organic material layer.
Specific examples of the hole injection material include metal porphyrin, oligothiophene, an arylamine-based organic material, a hexanitrilehexaazatriphenylene-based organic material, a quinacridone-based organic material, a perylene-based organic material, anthraquinone, polyaniline and polythiophene-based conductive polymer, and the like, but are not limited thereto.
Hole Transport Layer
The organic light emitting device according to the present disclosure can include a hole transport layer on the anode (or on the hole injection layer if there is a hole injection layer), if necessary.
The hole transport layer is a layer that receives holes from an anode or a hole injection layer and transports the holes to the light emitting layer. The hole transport material is suitably a material having large mobility to the holes, which can receive holes from the anode or the hole injection layer and transfer the holes to the light emitting layer.
Specific examples of the hole transport material include an arylamine-based organic material, a conductive polymer, a block copolymer in which a conjugate portion and a non-conjugate portion are present together, and the like, but are not limited thereto.
Electron Blocking Layer
The organic light emitting device according to the present disclosure can include an electron blocking layer between a hole transport layer and a light emitting layer, if necessary.
The electron blocking layer is a layer which is formed on the hole transport layer, is preferably provided in contact with the light emitting layer, and thus serves to control hole mobility, to prevent excessive movement of electrons, and to increase the probability of hole-electron bonding, thereby improving the efficiency of the organic light emitting device.
The electron blocking layer includes an electron blocking material, and an arylamine-based organic material can be used as the electron blocking material, but is not limited thereto.
Light Emitting Layer
The organic light emitting device according to the present disclosure includes a light emitting layer between an anode and a cathode, and the light emitting layer includes the first compound and the second compound as host materials. Specifically, the first compound functions as an N-type host material having an electron transport ability superior to a hole transport ability, and the second compound functions as a P-type host material having a hole transport ability superior to an electron transport ability, thereby maintaining the ratio of holes to electrons in the light emitting layer. Accordingly, the excitons emit lights evenly throughout the light emitting layer, so that the luminous efficiency and lifespan of the organic light emitting device can be simultaneously improved.
Hereinafter, the first compound and the second compound will be described.
(First Compound)
The first compound is the following Chemical Formula 1. Specifically, it has a structure in which carbazole and triazine are bonded together around benzofuran, so that electrons can be efficiently transferred to a dopant material. Accordingly, the first compound has an indolocarbazole-based structure and deuterium is substituted in each of the indolocarbazole core and its substituents to increase the probability of recombination of holes and electrons in the light emitting layer together with the second compound having an excellent hole transport ability.
In Chemical Formula 1:
Specifically, in Chemical Formula 1, n2 and n3 can each be an integer of 0 to 4, and n2+n3 is an integer selected within the range of 0 to 6.
Preferably, the compound of Chemical Formula 1 is the following Chemical Formula 1-1 or Chemical Formula 1-2:
Herein, in Chemical Formula 1-1, n2 and n3 are each an integer of 0 to 3. In Chemical Formula 1-2, n2 is an integer of 0 to 2, and n3 is an integer of 0 to 4.
Specifically, the first compound can be any one of the following Chemical Formulae 1A to 1E:
Herein, in Chemical Formulae 1A to 1D, n2 and n3 are each an integer of 0 to 3. In Chemical Formula 1E, n2 is an integer of 0 to 2, and n3 is an integer of 0 to 4.
More specifically, the compound of Chemical Formula 1C can be the following Chemical Formula 1C-1 (position 6 of the core), Chemical Formula 1C-2 (position 7 of the core), Chemical Formula 1C-3 (position 8 of the core), or Chemical Formula 1C-4 (position 9 of the core) depending on the substitution position of the N-containing 6-membered heterocyclic group:
In Chemical Formulae 1, 1-1, 1-2, 1A to 1E, and 1C-1 to 1C-4, Y is O or S.
In addition, in Chemical Formulae 1, 1-1, 1-2, 1A to 1E, and 1C-1 to 1C-4, X1, X2 and X3 are each independently CH or N, provided that at least one of X1, X2 and X3 is N.
Preferably, X1 to X3 are all N;
In addition, in Chemical Formulae 1, 1-1, 1-2, 1A to 1E, and 1C-1 to 1C-4, Ar1 and Ar2 are each independently substituted or unsubstituted C6-60 aryl or substituted or unsubstituted C2-60 heteroaryl containing at least one heteroatom selected from the group consisting of N, O and S.
For example, Ar1 is substituted or unsubstituted C6-60 aryl, and Ar2 is substituted or unsubstituted C6-60 aryl or substituted or unsubstituted C2-60 heteroaryl containing at least one heteroatom selected from the group consisting of N, O and S.
Preferably, Ar1 and Ar2 are each independently substituted or unsubstituted C6-20 aryl or substituted or unsubstituted C2-20 heteroaryl containing at least one heteroatom selected from the group consisting of N, O and S, wherein Ar1 and Ar2 are unsubstituted or substituted with at least one substituent selected from the group consisting of deuterium, C1-10 alkyl, and C6-20 aryl.
For example, Ar1 and Ar2 are each independently substituted or unsubstituted C6-20 aryl or substituted or unsubstituted C2-20 heteroaryl containing at least one heteroatom selected from the group consisting of N, O and S, wherein Ar1 and Ar2 are unsubstituted or substituted with at least one substituent selected from the group consisting of deuterium, C1-10 alkyl, and C6-20 aryl.
More preferably, Ar1 and Ar2 are each independently phenyl, biphenylyl, terphenylyl, naphthyl, phenanthryl, carbazolyl, dibenzofuranyl, dibenzothiophenyl, benzoxazolyl, or benzothiazolyl, wherein Ar1 and Ar2 can be unsubstituted or substituted with at least one substituent selected from the group consisting of deuterium, C1-10 alkyl, and C6-20 aryl.
More preferably, Ar1 and Ar2 can each independently be any one selected from the group consisting of:
Specifically, Ar1 and Ar2 can each independently be phenyl, biphenylyl, terphenylyl, naphthyl, phenanthrenyl, dibenzofuranyl, dibenzothiophenyl, carbazolyl, carbazolyl substituted with phenyl, benzoxazolyl, benzoxazolyl substituted with phenyl, benzothiazolyl, benzothiazolyl substituted with phenyl, phenyl substituted with 5 deuterium, biphenylyl substituted with 9 deuterium, terphenylyl substituted with 5 deuterium, dibenzofuranyl substituted with 7 deuterium, dibenzothiophenyl substituted with 7 deuterium, carbazolyl substituted with 8 deuterium, or carbazolyl substituted with phenyl substituted with 5 deuterium.
For example, Ar1 can be phenyl, biphenylyl, phenyl substituted with 5 deuterium, or biphenylyl substituted with 9 deuterium, and Ar2 can be phenyl, biphenylyl, terphenylyl, naphthyl, phenanthrenyl, dibenzofuranyl, dibenzothiophenyl, carbazolyl, carbazolyl substituted with phenyl, benzoxazolyl, benzoxazolyl substituted with phenyl, benzothiazolyl, benzothiazolyl substituted with phenyl, phenyl substituted with 5 deuterium, biphenylyl substituted with 9 deuterium, terphenylyl substituted with 5 deuterium, dibenzofuranyl substituted with 7 deuterium, dibenzothiophenyl substituted with 7 deuterium, carbazolyl substituted with 8 deuterium, or carbazolyl substituted with phenyl substituted with 5 deuterium.
In addition, at least one of Ar1 and Ar2 can be phenyl or phenyl substituted with 5 deuterium.
Also, Ar1 and Ar2 can be the same. Alternatively, Ar1 and Ar2 can be different.
In addition, in Chemical Formulae 1, 1-1, 1-2, 1A to 1E, or 1C-1 to 1C-4, R1, R2, and R3 are each independently hydrogen; deuterium; substituted or unsubstituted C6-60 aryl; or substituted or unsubstituted C2-60 heteroaryl containing at least one selected from the group consisting of N, O and S.
Preferably, each R1 can independently be hydrogen, deuterium, substituted or unsubstituted C6-20 aryl, or substituted or unsubstituted C2-20 heteroaryl containing at least one selected from the group consisting of N, O and S. More preferably, each R1 can independently be hydrogen, deuterium, phenyl, dibenzofuranyl, dibenzothiophenyl, carbazolyl, phenyl substituted with 5 deuterium, dibenzofuranyl substituted with 7 deuterium, dibenzothiophenyl substituted with 7 deuterium, or carbazolyl substituted with 8 deuterium. Most preferably, each R1 can independently be hydrogen, deuterium, or any one selected from the group consisting of:
Preferably, R2, and R3 can each independently be hydrogen, deuterium, substituted or unsubstituted C6-20 aryl, or substituted or unsubstituted C2-20 heteroaryl containing at least one selected from the group consisting of N, O and S. More preferably, R2, and R3 can each independently be hydrogen, deuterium, phenyl, dibenzothiophenyl, carbazolyl, or phenyl substituted with 5 deuterium. Most preferably, R2, and R3 can each independently be hydrogen, deuterium, or any one selected from the group consisting of:
In addition, in Chemical Formula 1, 1-1, 1-2, 1A to 1E, or 1C-1 to 1C-4,
the substituent can be any one of the substituents of the following Chemical Formulae 3a to 3i:
In Chemical Formulae 3a to 3i,
In addition, in Chemical Formula 1, 1-1, 1-2, 1A to 1E, or 1C-1 to 1C-4, n1 representing the number of R1 is 0, 1, 2, 3, 4, 5, 6, 7, or 8, and n2+n3 representing the sum of the number of R2 and the number of R3 is 0, 1, 2, 3, 4, 5, or 6.
Preferably, n1 can be 0, 1, 2, or 8, and n2+n3 can be 0, 1, 2, or 6. When n1 is 8, R1 can be deuterium, and when n2+n3 is 6, both R2 and R3 can be deuterium.
Meanwhile, the compound of Chemical Formula 1 may not be substituted with deuterium or can be substituted with at least one deuterium, and can be substituted with deuterium up to the total number of hydrogens in each compound. For example, the compound of Chemical Formula 1 can be unsubstituted or substituted with 1 to 51, 1 to 31, or 1 to 13 deuterium. In this case, a deuterium substitution rate of Chemical Formula 1 can be 0 to 100%. The ‘deuterium substitution rate’ refers to the number of deuterium contained in Chemical Formula 1 compared to the total number of hydrogens that can be present in Chemical Formula 1. For example, the deuterium substitution rate of Chemical Formula 1 can be 1% or more, 2% or more, 5% or more, 10% or more, 12% or more, or 15% or more, and 99% or less, 95% or less, 90% or less, 80% or less, 60% or less, 55% or less, 50% or less, or 48% or less.
For example, in Chemical Formula 1, 1-1, 1-2, 1A to 1E, or 1C-1 to 1C-4, at least one of Ar1 and Ar2 is deuterium-substituted C6-60 aryl; or deuterium-substituted C2-60 heteroaryl containing at least one heteroatom selected from the group consisting of N, O and S; or at least one of R1 to R3 is deuterium; deuterium-substituted C6-60 aryl; or deuterium-substituted C2-60 heteroaryl containing at least one heteroatom selected from the group consisting of N, O and S, and n1+n2+n3 is 1 or more.
Representative examples of the compound of Chemical Formula 1 are as follows:
Meanwhile, the compound of Chemical Formula 1 can be prepared by, for example, a preparation method as shown in Reaction Scheme 1 below, and other compounds can be prepared similarly. The preparation method can be more specifically described in Synthesis Examples described below.
In Reaction Scheme 1, Xa and X′ are each independently halogen. Preferably Xa is fluoro or chloro. Preferably, X′ is bromo, or chloro, more preferably chloro. In the Reaction Scheme 1, the definitions of other substituents are the same as described above.
Specifically, the compound of Chemical Formula 1 can be prepared through steps 1-1 and 1-2.
The step 1-1 is to prepare an intermediate compound A3 by the Suzuki-coupling reaction of starting materials A1 and A2. The Suzuki-coupling reaction is preferably performed in the presence of a palladium catalyst and a base, respectively, and the reactive group for the Suzuki-coupling reaction can be appropriately changed.
In addition, the step 1-2 is to prepare a compound of Chemical Formula 1 in which a carbazole group is introduced into the intermediate compound A3 by an amine substitution reaction of the intermediate compound A3 and the compound A4. The amine substitution reaction is preferably performed in the presence of a base or in the presence of a palladium catalyst and a base. In addition, the reactive group for the amine substitution reaction can also be appropriately changed as known in the art.
For example, in the Reaction Scheme 1, sodium tert-butoxide (NaOtBu), potassium carbonate (K2CO3), sodium bicarbonate (NaHCO3), cesium carbonate (Cs2CO3), sodium acetate (NaOAc), potassium acetate (KOAc), sodium ethoxide (NaOEt), triethylamine (Et3N), N,N-diisopropylethylamine (EtN(iPr)2), or the like can be used as the base component. Preferably, the base component can be sodium tert-butoxide (NaOtBu), potassium carbonate (K2CO3), cesium carbonate (Cs2CO3), potassium acetate (KOAc), or N,N-diisopropylethylamine (EtN(iPr)2). In particular, in the Reaction Scheme 1, potassium carbonate (K2CO3), sodium tert-butoxide (NaOtBu), or cesium carbonate (Cs2CO3) can be used as the base component.
In addition, in the Reaction Scheme 1, bis(tri-(tert-butyl)-phosphine)palladium(0) (Pd(P-tBu3)2), tetrakis(triphenylphosphine)-palladium(0) (Pd(PPh3)4), tris(dibenzylideneacetone)-dipalladium(0) (Pd2(dba)3), bis(dibenzylideneacetone)palladium(0) (Pd(dba)2), palladium(II) acetate (Pd(OAc)2), or the like can be used as the palladium catalyst. Preferably, the palladium catalyst can be bis(tri-(tert-butyl)phosphine)palladium(0) (Pd(P-tBu3)2), tetrakis(triphenylphosphine)-palladium(0) (Pd(PPh3)4), or bis(dibenzylideneacetone)palladium(0) (Pd(dba)2). In particular, in the Reaction Scheme 1, tetrakis(triphenylphosphine)palladium(0) (Pd(PPh3)4), or bis(tri-(tert-butyl)phosphine)palladium(0) (Pd(P-tBu3)2) can be used as the palladium catalyst.
The method for preparing the compound of Chemical Formula 1 can be more specifically described in Synthesis Examples described below.
(Second Compound)
The second compound is represented by Chemical Formula 2. Specifically, it has a structure in which two N atoms of an indolocarbazole core are substituted with an aryl group or a heteroaryl group, respectively, and deuterium is substituted in each of the indolocarbazole core and the aryl group or heteroaryl group. The second compound is characterized in that it contains at least two or more deuterium (D).
In Chemical Formula 2,
Preferably, the compound of Chemical Formula 2 can be any one of the following Chemical Formulae 2-1 to 2-5:
In Chemical Formulae 2 and 2-1 to 2-5, Ar3 and Ar4 are each independently substituted or unsubstituted C6-60 aryl or substituted or unsubstituted C2-60 heteroaryl containing at least one heteroatom selected from the group consisting of O and S, provided that at least one of Ar3 and Ar4 is substituted with at least one deuterium.
For example, Ar3 can be substituted or unsubstituted C6-60 aryl, and Ar4 can be substituted or unsubstituted C6-60 aryl or substituted or unsubstituted C2-60 heteroaryl containing at least one heteroatom selected from the group consisting of N, O and S, provided that at least one of Ar3 and Ar4 is substituted with at least one deuterium.
Preferably, in Chemical Formulae 2 and 2-1 to 2-5, Ar3 and Ar4 can each independently be substituted or unsubstituted C6-20 aryl or substituted or unsubstituted C2-20 heteroaryl containing at least one heteroatom selected from the group consisting of O and S. More preferably, Ar3 and Ar4 can each independently be phenyl, biphenylyl, terphenylyl, dibenzofuranyl, dibenzothiophenyl, dimethylfluorenyl, dibenzofuranyl phenyl, dibenzothiophenyl phenyl, or dimethylfluorenyl phenyl, and the phenyl, biphenylyl, terphenylyl, dibenzofuranyl, dibenzothiophenyl, dimethylfluorenyl, dibenzofuranyl phenyl, dibenzothiophenyl phenyl, or dimethylfluorenyl phenyl can be unsubstituted or substituted with deuterium. However, at least one of Ar3 and Ar4 is substituted with at least one deuterium.
For example, one of Ar3 and Ar4 can be phenyl, biphenylyl, or terphenylyl, and the other can be phenyl, biphenylyl, terphenylyl, dibenzofuranyl, dibenzothiophenyl, dimethylfluorenyl, dibenzofuranyl phenyl, dibenzothiophenyl phenyl, or dimethylfluorenyl phenyl, and the phenyl, biphenylyl, terphenylyl, dibenzofuranyl, dibenzothiophenyl, dimethylfluorenyl, dibenzofuranyl phenyl, dibenzothiophenyl phenyl, or dimethylfluorenyl phenyl can be unsubstituted or substituted with deuterium. However, at least one of Ar3 and Ar4 is substituted with at least one deuterium.
Specifically, one of Ar3 and Ar4 can be biphenylyl, or deuterium-substituted biphenylyl, and the other can be biphenylyl, deuterium-substituted biphenylyl, terphenylyl, deuterium-substituted terphenylyl, dibenzofuranyl, deuterium-substituted dibenzofuranyl, dibenzothiophenyl, deuterium-substituted dibenzothiophenyl, dimethylfluorenyl, deuterium-substituted dimethylfluorenyl, dibenzofuranyl phenyl, deuterium-substituted dibenzofuranyl phenyl, dibenzothiophenyl phenyl, deuterium-substituted dibenzothiophenyl phenyl, dimethylfluorenyl phenyl, or deuterium-substituted dimethylfluorenyl phenyl. However, at least one of Ar3 and Ar4 is substituted with at least one deuterium.
Alternatively, Ar3 and Ar4 are each independently any one selected from the group consisting of the following structural formulae, provided that at least one of Ar3 and Ar4 is substituted with at least one deuterium:
More preferably, in Chemical Formulae 2 and 2-1 to 2-5, Ar3 can be substituted with at least one deuterium, and Ar4 can be substituted with at least one deuterium.
For example, in Chemical Formulae 2 and 2-1 to 2-5, Ar3 and Ar4 can each independently be any one selected from the group consisting of:
For example, Ar3 can be biphenylyl, biphenylyl substituted with 1 deuterium, biphenylyl substituted with 3 to 6 deuterium, biphenylyl substituted with 8 deuterium, or biphenylyl substituted with 9 deuterium, and Ar4 can be biphenylyl, terphenylyl, dibenzofuranyl, dibenzothiophenyl, fluorenyl, dibenzofuranyl-substituted phenyl, dibenzothiophenyl-substituted phenyl, fluorenyl-substituted phenyl, biphenylyl substituted with 1 deuterium, biphenylyl substituted with 3 to 6 deuterium, biphenylyl substituted with 8 deuterium, biphenylyl substituted with 9 deuterium, terphenylyl substituted with 5 to 7 deuterium, dibenzofuranyl substituted with 6 to 7 deuterium, dibenzothiophenyl substituted with 6 to 7 deuterium, fluorenyl substituted with 7 deuterium, phenyl substituted with dibenzofuranyl substituted with 6 to 7 deuterium, phenyl substituted with dibenzothiophenyl substituted with 6 to 7 deuterium, phenyl substituted with fluorenyl substituted with 7 deuterium, phenyl substituted with dibenzofuranyl substituted with 4 deuterium, phenyl substituted with dibenzothiophenyl substituted with 4 deuterium, or phenyl substituted with fluorenyl substituted with 4 deuterium. However, at least one of Ar3 and Ar4 is substituted with at least one deuterium.
Preferably, Ar3 and Ar4 are each independently substituted with at least one deuterium.
Meanwhile, in Chemical Formulae 2 and 2-1 to 2-5, each R4 is independently hydrogen, deuterium, substituted or unsubstituted C6-60 aryl, or substituted or unsubstituted C2-60 heteroaryl containing at least one heteroatom selected from the group consisting of N, O and S, provided that at least one of R4 is deuterium.
Preferably, each R4 can independently be hydrogen, deuterium, substituted or unsubstituted C6-20 aryl, or substituted or unsubstituted C2-20 heteroaryl containing at least one heteroatom selected from the group consisting of N, O and S. More preferably, each R4 can independently be hydrogen or deuterium. However, at least one of R4 is deuterium. Preferably, at least two of R4 are deuterium, and more preferably, at least six of R4 are deuterium.
For example, in Chemical Formulae 2 and 2-1 to 2-5, Ar3 is substituted with at least one deuterium, and Ar4 is substituted with at least one deuterium. At least one of R4 can be deuterium. Preferably, at least two of R4 can be deuterium, and more preferably, at least six of R4 can be deuterium.
The compound of Chemical Formula 2 can be any one of Chemical Formula 2A-1 to Chemical Formula 2A-9, Chemical Formula 2B-1 to Chemical Formula 2B-8, Chemical Formula 2C-1 to Chemical Formula 2C-7, Chemical Formula 2D-1 to Chemical Formula 2D-6, Chemical Formula 2E-1 to Chemical Formula 2E-5, and Chemical Formula 2F-1 to Chemical Formula 2F-3:
In addition, the compound of Chemical Formula 2 has an indolocarbazole-based structure, and deuterium is substituted in each of the indolocarbazole core and its substituents. It is substituted with at least two or more, preferably at least three or more deuterium, and can be substituted with deuterium up to the total number of hydrogens in each compound. For example, the compound of Chemical Formula 2 can be substituted with 2 to 50, 2 to 46, or 2 to 44 deuterium. Preferably, it can be substituted with 3 or more, 4 or more, 6 or more, 8 or more, 10 or more, or 14 or more deuterium. In this case, a deuterium substitution rate of Chemical Formula 2 can be 50% or more to 100% or less. The ‘deuterium substitution rate’ refers to the number of deuterium contained in Chemical Formula 2 compared to the total number of hydrogens that can be present in Chemical Formula 2. For example, the deuterium substitution rate of Chemical Formula 2 can be 52% or more, 55% or more, 58% or more, 60% or more, 65% or more, 70% or more, 75% or more, 80% or more, 85% or more, or 90% or more, and 99% or less, 98% or less, 97% or less, 96% or less, 95% or less, 94% or less, 93% or less, or 92% or less.
Representative examples of the compound of Chemical Formula 2 are as follows:
Meanwhile, the compound of Chemical Formula 2 can be prepared by, for example, a preparation method as shown in Reaction Scheme 2 below. The preparation method can be more specifically described in Synthesis Examples described below.
In Reaction Scheme 2, X″s are the same as or different from each other, and each independently represents halogen. Preferably, each X″ is bromo or chloro, and more preferably, both are bromo. In the Reaction Scheme 2, the definitions of the other substituents are the same as described above.
Specifically, the compound of Chemical Formula 2 can be prepared through steps 2-1 and 2-2.
The step 2-1 is to prepare an intermediate compound B3 by an amine substitution reaction of a starting material B1 and the compound B2. Thereafter, the step 2-2 is to prepare the compound of Chemical Formula 2 by an amine substitution reaction of the intermediate compound B3 and the compound B4. The amine substitution reaction is preferably performed in the presence of a base or in the presence of a palladium catalyst and a base. In addition, the reactive group for the amine substitution reaction can also be appropriately changed as known in the art.
For example, in the Reaction Scheme 2, sodium tert-butoxide (NaOtBu), potassium carbonate (K2CO3), sodium bicarbonate (NaHCO3), cesium carbonate (Cs2CO3), sodium acetate (NaOAc), potassium acetate (KOAc), sodium ethoxide (NaOEt), triethylamine (Et3N), N,N-diisopropylethylamine (EtN(iPr)2), or the like can be used as the base component. Preferably, the base component can be sodium tert-butoxide (NaOtBu), potassium carbonate (K2CO3), cesium carbonate (Cs2CO3), potassium acetate (KOAc), or N,N-diisopropylethylamine (EtN(iPr)2). In particular, in the Reaction Scheme 2, sodium tert-butoxide (NaOtBu) can be used as the base component.
In addition, in the Reaction Scheme 2, bis(tri-(tert-butyl)phosphine)palladium(0) (Pd(P-tBu3)2), tetrakis(triphenylphosphine)-palladium(0) (Pd(PPh3)4), tris(dibenzylideneacetone)-dipalladium(0) (Pd2(dba)3), bis(dibenzylideneacetone)palladium(0) (Pd(dba)2), palladium(II) acetate (Pd(OAc)2), or the like can be used as the palladium catalyst. Preferably, the palladium catalyst can be bis(tri-(tert-butyl)-phosphine)palladium(0) (Pd(P-tBu3)2), tetrakis(triphenylphosphine)-palladium(0) (Pd(PPh3)4), or bis(dibenzylideneacetone)palladium(0) (Pd(dba)2). In particular, in Reaction Scheme 2, bis(tri-(tert-butyl)phosphine)palladium(0) (Pd(P-tBu3)2) can be used as the palladium catalyst.
The method for preparing the compound of Chemical Formula 2 can be more specifically described in Synthesis Examples described below.
In addition, the first compound and the second compound can be included in the light emitting layer at a weight ratio of 1:9 to 9:1. When the first compound is included in the light emitting layer in an excessively small amount, electron transport in the light emitting layer is not smooth, and thus holes and electrons are not balanced throughout the device, which can cause problems in voltage, efficiency, and lifespan of the manufactured device. When the second compound is included in the light emitting layer in an excessively small amount compared to the first compound, there can be a problem in that the lifespan is reduced. For example, a weight ratio of the first compound and the second compound in the light emitting layer can be 2:8 to 8:2, 3:7 to 7:3, 4:6 to 6:4, or 4:6 to 5:5.
Meanwhile, the light emitting layer can further include a dopant material other than the two kinds of host materials. Examples of the dopant material include an aromatic amine derivative, a styrylamine compound, a boron complex, a fluoranthene compound, a metal complex, and the like. Specifically, the aromatic amine derivative is a substituted or unsubstituted fused aromatic ring derivative having an arylamino group, and examples thereof include pyrene, anthracene, chrysene, periflanthene and the like, which have an arylamino group. The styrylamine compound is a compound where at least one arylvinyl group is substituted in substituted or unsubstituted arylamine, in which one or two or more substituent groups selected from the group consisting of an aryl group, a silyl group, an alkyl group, a cycloalkyl group, and an arylamino group are substituted or unsubstituted. Specific examples thereof include styrylamine, styryldiamine, styryltriamine, styryltetramine, and the like, but are not limited thereto. Further, the metal complex includes an iridium complex, a platinum complex, and the like, but is not limited thereto. Specifically, the dopant material is an iridium-based metal complex.
For example, the light emitting layer can include a green dopant material. In particular, the combination of the compound of Chemical Formula 1 as a first host and the compound of Chemical Formula 2 as a second host can facilitate energy transfer to the green dopant in the green light emitting layer, and thus can reduce the driving voltage and increase efficiency and lifespan in the organic light emitting device.
Herein, the dopant material can be included in the light emitting layer in an amount of 1 to 25 wt % based on a total weight of the host material (the sum of the weight of the compound of Chemical Formula 1 and the weight of the compound of Chemical Formula 2) and the dopant material. For example, the dopant material can be included in an amount of 2 to 22 wt %, 5 to 20 wt %, 8 to 20 wt %, or 10 to 18 wt %.
Hole Blocking Layer
The organic light emitting device according to the present disclosure can include a hole blocking layer between a light emitting layer and an electron transport layer (or an electron transport and injection layer) to be described later, if necessary.
The hole blocking layer means a layer which is formed on the light emitting layer, is preferably provided in contact with the light emitting layer, and thus serves to control electron mobility, to prevent excessive movement of holes, and to increase the probability of hole-electron bonding, thereby improving the efficiency of the organic light emitting device.
The hole blocking layer includes a hole blocking material, and as an example of such a hole blocking material, compounds having an electron attracting group such as azine-based derivatives including triazine; triazole derivatives; oxadiazole derivatives; phenanthroline derivatives; phosphine oxide derivatives can be used, but is not limited thereto.
Electron Transport Layer
The organic light emitting device according to the present disclosure can include an electron transport layer on the light emitting layer (or on the hole blocking layer if there is a hole blocking layer), if necessary.
The electron transport layer receives electrons from a cathode or an electron injection layer formed on the cathode and transports the electrons to a light emitting layer. The electron transport layer includes an electron transport material, and the electron transport material is suitably a material which can receive electrons well from a cathode and transfer the electrons to a light emitting layer and has large mobility for electrons.
Specific examples of the electron transport material include: an A1 complex of 8-hydroxyquinoline; a complex including Alq3; an organic radical compound; a hydroxyflavone-metal complex; and the like, but are not limited thereto. The electron transport layer can be used with any desired cathode material, as used in the related art. In particular, appropriate examples of the cathode material are typical materials having a low work function, followed by an aluminum layer or a silver layer. Specific examples thereof include cesium, barium, calcium, ytterbium, and samarium, in each case followed by an aluminum layer or a silver layer.
Electron Transport and Injection Layer
The organic light emitting device according to the present disclosure can include an electron injection layer on the light emitting layer (or on the hole blocking layer if there is a hole blocking layer, or on the electron transport layer if there is an electron transport layer), if necessary. The organic light emitting device according to the present disclosure can include an electron transport and injection layer between a light emitting layer (or on the hole blocking layer if there is a hole blocking layer) and a cathode, if necessary.
The electron transport and injection layer is a layer that simultaneously serves as an electron transport layer and an electron injection layer by injecting electrons from an electrode and transferring the received electrons to a light emitting layer, and is formed on the light emitting layer or the electron blocking layer. An electron injection and transport material is suitably a material which can receive electrons well from a cathode and transfer the electrons to alight emitting layer and has large mobility for electrons. Specific examples of the electron injection and transport material include: an A1 complex of 8-hydroxyquinoline; a complex including Alq3; an organic radical compound; a hydroxyflavone-metal complex; a triazine derivative, and the like, but are not limited thereto. Alternatively, it can be used together with fluorenone, anthraquinodimethane, diphenoquinone, thiopyran dioxide, oxazole, oxadiazole, triazole, imidazole, perylenetetracarboxylic acid, fluorenylidene methane, anthrone, or derivatives thereof, a metal complex compound, a nitrogen-containing 5-membered ring derivative, or the like, but are not limited thereto.
The electron transport and injection layer can also be formed separately such as an electron injection layer and an electron transport layer. In this case, the electron transport layer is formed on the light emitting layer or the hole blocking layer, and the electron injection and transport material described above can be used as the electron transport material included in the electron transport layer. In addition, the electron injection layer is formed on the electron transport layer, and the electron injection material included in the electron injection layer can include LiF, NaCl, CsF, Li2O, BaO, fluorenone, anthraquinodimethane, diphenoquinone, thiopyran dioxide, oxazole, oxadiazole, triazole, imidazole, perylenetetracarboxylic acid, fluorenylidene methane, anthrone, and derivatives thereof, a metal complex compound, a nitrogen-containing 5-membered ring derivative, and the like.
Examples of the metal complex compound include 8-hydroxyquinolinato lithium, bis(8-hydroxyquinolinato)zinc, bis(8-hydroxyquinolinato)copper, bis(8-hydroxyquinolinato)manganese, tris(8-hydroxyquinolinato)aluminum, tris(2-methyl-8-hydroxyquinolinato)aluminum, tris(8-hydroxyquinolinato)gallium, bis(10-hydroxybenzo[h]quinolinato)-beryllium, bis(10-hydroxybenzo[h]quinolinato)zinc, bis(2-methyl-8-quinolinato)chlorogallium, bis(2-methyl-8-quinolinato)(o-cresolato)gallium, bis(2-methyl-8-quinolinato)(1-naphtholato)aluminum, bis(2-methyl-8-quinolinato)(2-naphtholato)gallium, and the like, but are not limited thereto.
Organic Light Emitting Device
A structure of the organic light emitting device according to the present disclosure is illustrated in
The organic light emitting device according to the present disclosure can be manufactured by sequentially laminating the above-described components. In this case, the organic light emitting device can be manufactured by depositing a metal, metal oxides having conductivity, or an alloy thereof on the substrate using a PVD (physical vapor deposition) method such as a sputtering method or an e-beam evaporation method to form an anode, forming the above-mentioned respective layers thereon, and then depositing a material that can be used as the cathode thereon. In addition to such a method, the organic light emitting device can be manufactured by sequentially depositing the above-described components from a cathode material to an anode material in the reverse order on a substrate (WO 2003/012890). Further, the light emitting layer can be formed using the host and the dopant by a solution coating method as well as a vacuum deposition method. Herein, the solution coating method means a spin coating, a dip coating, a doctor blading, an inkjet printing, a screen printing, a spray method, a roll coating, or the like, but is not limited thereto.
In addition to such a method, the organic light emitting device can be manufactured by sequentially depositing a cathode material, an organic material layer and an anode material on a substrate (International Publication WO2003/012890). However, the manufacturing method is not limited thereto.
The organic light emitting device according to the present disclosure can be a bottom emission device, a top emission device, or a double-sided light emitting device, and in particular, can be a bottom emission device requiring relatively high luminous efficiency.
Hereinafter, it will be described in more detail to help the understanding of the present invention. However, the following examples are presented for illustrative purposes only, and are not intended to limit the scope of the present invention.
(Preparation of First Compound)
2-bromo-5-chlorophenol (20 g, 96.4 mmol) and (2,5-difluorophenyl)boronic acid (15.2 g, 96.4 mmol) were added to 400 ml of tetrahydrofuran under a nitrogen atmosphere, and the mixture was stirred and refluxed. Then, potassium carbonate (40 g, 289.2 mmol) was dissolved in 40 ml of water, and then added thereto. Thereafter, it was stirred sufficiently, followed by adding tetrakis(triphenylphosphine)palladium (3.3 g, 2.9 mmol). After 1 hour of reaction, cooling was performed to room temperature. Then, the organic layer was separated from the water layer, and then the organic layer was distilled to remove the solvent. Then, this was dissolved again in 464 mL of chloroform corresponding to 20 times (by volume), and washed twice with water. Thereafter, the organic layer was separated, treated with anhydrous magnesium sulfate, stirred, then filtered, and the filtrate was distilled under reduced pressure. The concentrated compound was recrystallized using chloroform and ethyl acetate to prepare Compound 1-1-a in the form of white solid (16.2 g, 70%, MS: [M+H]+=241.6).
The Compound 1-1-a (20 g, 83.1 mmol) was added to 400 mL of dimethylformamide under a nitrogen atmosphere, and the mixture was stirred and refluxed. Then, cesium carbonate (81.2 g, 249.3 mmol) was added thereto, followed by heating and stirring. After 3 hours of reaction, cooling was performed to room temperature, and the resulting solid was filtered. Then, the solid was dissolved in 550 mL of chloroform corresponding to 30 times (by volume), and washed twice with water. Thereafter, the organic layer was separated, treated with anhydrous magnesium sulfate, stirred, then filtered, and the filtrate was distilled under reduced pressure. The concentrated compound was recrystallized using chloroform and ethyl acetate to prepare Compound 1-1-b in the form of white solid (13.2 g, 72%, MS: [M+H]+=221.6).
The Compound 1-1-b (20 g, 90.6 mmol) and bis(pinacolato)diboron (23 g, 90.6 mmol) were added to 400 mL of 1,4-dioxane under a nitrogen atmosphere, and the mixture was stirred and refluxed. Thereafter, potassium acetate (57.7 g, 271.9 mmol) was added thereto, and sufficiently stirred, followed by adding bis(dibenzylideneacetone)palladium (1.6 g, 2.7 mmol) and tricyclohexylphosphine (1.5 g, 5.4 mmol). After 7 hours of reaction, cooling was performed to room temperature, the organic layer was filtered to remove the salt, and the filtered organic layer was distilled to remove the solvent. Then, this was dissolved again in 283 mL of chloroform corresponding to 10 times (by volume), and washed twice with water. Thereafter, the organic layer was separated, treated with anhydrous magnesium sulfate, stirred, then filtered, and the filtrate was distilled under reduced pressure. The concentrated compound was recrystallized using chloroform and ethanol to prepare Compound 1-1-c in the form of white solid (20.9 g, 74%, MS: [M+H]+=313.2).
The Compound 1-1-c (20 g, 64.1 mmol) and 2-chloro-4,6-diphenyl-1,3,5-triazine (17.2 g, 64.1 mmol) were added to 400 ml of tetrahydrofuran under a nitrogen atmosphere, and the mixture was stirred and refluxed. Then, potassium carbonate (26.6 g, 192.2 mmol) was dissolved in 27 ml of water, and then added thereto. Thereafter, it was stirred sufficiently, followed by adding tetrakis(triphenylphosphine)palladium (2.2 g, 1.9 mmol). After 3 hours of reaction, cooling was performed to room temperature. Then, the organic layer was separated from the water layer, and then the organic layer was distilled to remove the solvent. Then, this was dissolved again in 535 mL of chloroform corresponding to 20 times (by volume), and washed twice with water. Thereafter, the organic layer was separated, treated with anhydrous magnesium sulfate, stirred, then filtered, and the filtrate was distilled under reduced pressure. The concentrated compound was recrystallized using chloroform and ethyl acetate to prepare Compound 1-1-d in the form of white solid (19.3 g, 72%, MS: [M+H]+=418.4).
The Compound 1-1-d (20 g, 47.9 mmol) and 9H-carbazole-1,2,3,4,5,6,7,8-d8 (8.4 g, 47.9 mmol) were added to 400 mL of dimethylformamide under a nitrogen atmosphere, and the mixture was stirred and refluxed. Then, cesium carbonate (46.8 g, 143.7 mmol) was added thereto, followed by heating and stirring. After 3 hours of reaction, cooling was performed to room temperature, and the resulting solid was filtered. Then, the solid was dissolved in 823 mL of chloroform corresponding to 30 times (by volume), and washed twice with water. Thereafter, the organic layer was separated, treated with anhydrous magnesium sulfate, stirred, then filtered, and the filtrate was distilled under reduced pressure. The concentrated compound was recrystallized using chloroform and ethyl acetate to prepare Compound 1-1 in the form of white solid (20.9 g, 76%, MS: [M+H]+=573.7).
Compound 1-2 (MS: [M+H]+=649.8) was prepared in the same manner as in the preparation of Compound 1-1 in Synthesis Example 1, except that (2,6-difluorophenyl)boronic acid and 2-([1,1′-biphenyl]-3-yl)-4-chloro-6-phenyl-1,3,5-triazine was used instead of (2,5-difluorophenyl)boronic acid and 2-chloro-4,6-diphenyl-1,3,5-triazine, respectively, in Synthesis Example 1.
Compound 1-3 (MS: [M+H]+=679.8) was prepared in the same manner as in the preparation of Compound 1-1 in Synthesis Example 1, except that (2,4-difluorophenyl)boronic acid and 2-chloro-4-(dibenzo[b,d]thiophen-3-yl)-6-phenyl-1,3,5-triazine were used instead of (2,5-difluorophenyl)boronic acid and 2-chloro-4,6-diphenyl-1,3,5-triazine, respectively, in Synthesis Example 1.
Compound 1-4 (MS: [M+H]+=679.8) was prepared in the same manner as in the preparation of Compound 1-1 in Synthesis Example 1, except that 2-bromo-3-chlorophenol, (2,4-difluorophenyl)boronic acid and 2-chloro-4-(dibenzo[b,d]thiophen-4-yl)-6-phenyl-1,3,5-triazine were used instead of 2-bromo-5-chlorophenol, (2,5-difluorophenyl)boronic acid and 2-chloro-4,6-diphenyl-1,3,5-triazine, respectively, in Synthesis Example 1.
Compound 1-5 (MS: [M+H]+=746.9) was prepared in the same manner as in the preparation of Compound 1-1 in Synthesis Example 1, except that 2-bromo-6-chlorophenol, (2,4-difluorophenyl)boronic acid, 2-chloro-4-(phenanthren-2-yl)-6-phenyl-1,3,5-triazine and 4-(phenyl-d5)-9H-carbazole were used instead of 2-bromo-5-chlorophenol, (2,5-difluorophenyl)boronic acid, 2-chloro-4,6-diphenyl-1,3,5-triazine, and 9H-carbazole-1,2,3,4,5,6,7,8-d8, respectively, in Synthesis Example 1.
Compound 1-6 (MS: [M+H]+=645.8) was prepared in the same manner as in the preparation of Compound 1-1 in Synthesis Example 1, except that 6-bromo-3-chloro-2-fluorophenol, (2-fluorophenyl)boronic acid, 4-chloro-2,6-diphenylpyrimidine and 4-(phenyl-d5)-9H-carbazole were used instead of 2-bromo-5-chlorophenol, (2,5-difluorophenyl)boronic acid, 2-chloro-4,6-diphenyl-1,3,5-triazine, and 9H-carbazole-1,2,3,4,5,6,7,8-d8, respectively, in Synthesis Example 1.
Compound 1-7 (MS: [M+H]+=647.8) was prepared in the same manner as in the preparation of Compound 1-1 in Synthesis Example 1, except that 2-bromo-3-chlorophe-4,5,6-d3-nol, (2,4-difluorophenyl-3,5,6-d3)boronic acid and 3-phenyl-9H-carbazole were used instead of 2-bromo-5-chlorophenol, (2,5-difluorophenyl)boronic acid, and 9H-carbazole-1,2,3,4,5,6,7,8-d8, respectively, in Synthesis Example 1.
Compound 1-8 (MS: [M+H]+=722.8) was prepared in the same manner as in the preparation of Compound 1-1 in Synthesis Example 1, except that 2-bromo-3-chlorophenol, (2,6-difluoro-[1,1′-biphenyl]-3-yl)boronic acid, 2-chloro-4-phenyl-6-(phenyl-d5)-1,3,5-triazine and 1-phenyl-9H-carbazole were used instead of 2-bromo-5-chlorophenol, (2,5-difluorophenyl)boronic acid, 2-chloro-4,6-diphenyl-1,3,5-triazine, and 9H-carbazole-1,2,3,4,5,6,7,8-d8, respectively, in Synthesis Example 1.
Compound 1-9 (MS: [M+H]+=755.9) was prepared in the same manner as in the preparation of Compound 1-1 in Synthesis Example 1, except that 2-bromo-3-chloro-6-(dibenzo[b,d]thiophen-4-yl)phenol and (2,4-difluorophenyl)-boronic acid were used instead of 2-bromo-5-chlorophenol and (2,5-difluorophenyl)boronic acid, respectively, in Synthesis Example 1.
Compound 1-10 (MS: [M+H]+=720.9) was prepared in the same manner as in the preparation of Compound 1-1 in Synthesis Example 1, except that 2-bromo-3-chlorophenol, (2,3-difluorophenyl)boronic acid, 2-chloro-6-phenyl-4-(phenyl-d5)pyridine and 1,3-diphenyl-9H-carbazole were used instead of 2-bromo-5-chlorophenol, (2,5-difluorophenyl)boronic acid, 2-chloro-4,6-diphenyl-1,3,5-triazine, and 9H-carbazole-1,2,3,4,5,6,7,8-d8, respectively, in Synthesis Example 1.
Compound 1-11 (MS: [M+H]+=644.7) was prepared in the same manner as in the preparation of Compound 1-1 in Synthesis Example 1, except that 2-bromo-3-chloro-6-fluorophenol, (2-fluoro-[1,1′-biphenyl]-3-yl)boronic acid, 4-chloro-6-phenyl-2-(phenyl-d5)pyridine and 9H-carbazole were used instead of 2-bromo-5-chlorophenol, (2,5-difluorophenyl)boronic acid, 2-chloro-4,6-diphenyl-1,3,5-triazine, and 9H-carbazole-1,2,3,4,5,6,7,8-d8, respectively, in Synthesis Example 1.
1-bromo-3-iodo-2-(methylthio)benzene (100 g, 304 mmol) and (3-chlorophenyl)boronic acid (47.5 g, 304 mmol) were added to 2000 ml of tetrahydrofuran under a nitrogen atmosphere, and the mixture was stirred and refluxed. Then, potassium carbonate (126 g, 911.9 mmol) was dissolved in 126 ml of water, and then added thereto. Thereafter, it was stirred sufficiently, followed by adding tetrakis(triphenylphosphine)palladium (10.5 g, 9.1 mmol). After 1 hour of reaction, cooling was performed to room temperature. Then, the organic layer was separated from the water layer, and then the organic layer was distilled to remove the solvent. Then, this was dissolved again in 1907 mL of chloroform corresponding to 20 times (by volume), and washed twice with water. Thereafter, the organic layer was separated, treated with anhydrous magnesium sulfate, stirred, then filtered, and the filtrate was distilled under reduced pressure. The concentrated compound was recrystallized using chloroform and ethyl acetate to prepare Compound 1-12-a in the form of white solid (81 g, 85%, MS: [M+H]+=314.6).
The Compound 1-12-a (78.7 g, 252.3 mmol) was dissolved in 750 mL of acetic acid under a nitrogen atmosphere, and then cooled to 0° C. 35% hydrogen peroxide (8.6 g, 252.3 mmol) was added thereto, and stirred at room temperature for 2 hours. When the reaction was completed, water was added for neutralization. Then, the organic layer was separated, treated with anhydrous magnesium sulfate, stirred, then filtered, and the filtrate was distilled under reduced pressure to prepare Compound 1-12-b (72 g, 87%, MS: [M+H]+=328.9).
The Compound 1-12-b (72.0 g, 219.6 mmol) and 290 mL of sulfuric acid were added to a flask at 5° C., and the temperature was gradually increased while stirring, followed by stirring at room temperature for 1.5 hours. After the reaction, it was added dropwise to 3000 mL of ice water, and neutralized with an aqueous potassium carbonate solution. Then, the organic layer was separated using ethyl acetate, treated with anhydrous magnesium sulfate, stirred, then filtered, and the filtrate was distilled under reduced pressure to prepare Compound 1-12-c (40.3 g, 62%, MS: [M+H]+=296.9).
The Compound 1-12-c (40 g, 134.4 mmol) and bis(pinacolato)diboron (34.1 g, 134.4 mmol) were added to 800 mL of 1,4-dioxane under a nitrogen atmosphere, and the mixture was stirred and refluxed. Thereafter, potassium acetate (85.6 g, 403.2 mmol) was added thereto, and sufficiently stirred, followed by adding bis(dibenzylideneacetone)palladium (2.3 g, 4 mmol) and tricyclohexylphosphine (2.3 g, 8.1 mmol). After 5 hours of reaction, cooling was performed to room temperature, the organic layer was filtered to remove the salt, and the filtered organic layer was distilled to remove the solvent. Then, this was dissolved again in 463 mL of chloroform corresponding to 10 times (by volume), and washed twice with water. Thereafter, the organic layer was separated, treated with anhydrous magnesium sulfate, stirred, then filtered, and the filtrate was distilled under reduced pressure. The concentrated compound was recrystallized using chloroform and ethanol to prepare Compound 1-12-d in the form of white solid (23.2 g, 50%, MS: [M+H]+=345.7).
The Compound 1-12-d (23 g, 66.7 mmol) and 2-chloro-4-phenyl-6-(phenyl-d5)-1,3,5-triazine (18.2 g, 66.7 mmol) were added to 460 ml of tetrahydrofuran under a nitrogen atmosphere, and the mixture was stirred and refluxed. Then, potassium carbonate (27.7 g, 200.2 mmol) was dissolved in 28 ml of water, and then added thereto. Thereafter, it was stirred sufficiently, followed by adding tetrakis(triphenylphosphine)palladium (2.3 g, 2 mmol). After 2 hours of reaction, cooling was performed to room temperature. Then, the organic layer was separated from the water layer, and then the organic layer was distilled to remove the solvent. Then, this was dissolved again in 606 mL of chloroform corresponding to 20 times (by volume), and washed twice with water. Thereafter, the organic layer was separated, treated with anhydrous magnesium sulfate, stirred, then filtered, and the filtrate was distilled under reduced pressure. The concentrated compound was recrystallized using chloroform and ethyl acetate to prepare Compound 1-12-e in the form of yellow solid (21.5 g, 71%, MS: [M+H]+=455.1).
The Compound 1-12-e (20 g, 44 mmol) and 3-phenyl-9H-carbazole (10.7 g, 44 mmol) were added to 400 mL of xylene under a nitrogen atmosphere, and the mixture was stirred and refluxed. Then, sodium tert-butoxide (12.7 g, 131.9 mmol) was added thereto, and sufficiently stirred, followed by adding bis(tri-tertiary-butylphosphine)palladium (0.7 g, 1.3 mmol). After 4 hours of reaction, cooling was performed to room temperature, the organic layer was filtered to remove the salt, and the filtered organic layer was distilled to remove the solvent. Then, this was dissolved again in 291 mL of chloroform corresponding to 10 times (by volume), and washed twice with water. Thereafter, the organic layer was separated, treated with anhydrous magnesium sulfate, stirred, then filtered, and the filtrate was distilled under reduced pressure. The concentrated compound was recrystallized using chloroform and ethyl acetate to prepare Compound 1-12 in the form of yellow solid (19.2 g, 66%, MS: [M+H]+=662.2).
Compound 1-13 (MS: [M+H]+=667.3) was prepared in the same manner as in the preparation of Compound 1-12 in Synthesis Example 12, except that 1-bromo-4-iodo-3-(methylthio)benzene, (2-chlorophenyl)boronic acid, 2-chloro-4,6-bis(phenyl-d5)-1,3,5-triazine and 4-phenyl-9H-carbazole were used instead of 1-bromo-3-iodo-2-(methylthio)benzene, (3-chlorophenyl)boronic acid, 2-chloro-4-phenyl-6-(phenyl-d5)-1,3,5-triazine and 3-phenyl-9H-carbazole, respectively, in Synthesis Example 12.
Compound 1-14 (MS: [M+H]+=679.3) was prepared in the same manner as in the preparation of Compound 1-12 in Synthesis Example 12, except that 4-bromo-1-iodo-2-(methylthio)benzene, (3-chlorophenyl)boronic acid, 2-chloro-4-(dibenzo[b,d]furan-1-yl)-6-phenyl-1,3,5-triazine and 9H-carbazole-1,2,3,4,5,6,7,8-d8 were used instead of 1-bromo-3-iodo-2-(methylthio)benzene, (3-chlorophenyl)boronic acid, 2-chloro-4-phenyl-6-(phenyl-d5)-1,3,5-triazine and 3-phenyl-9H-carbazole, respectively, in Synthesis Example 12.
Compound 1-15 (MS: [M+H]+=738.3) was prepared in the same manner as in the preparation of Compound 1-12 in Synthesis Example 12, except that (4-bromo-3-iodo-[1,1′-biphenyl]-2-yl)(methyl)sulfane, (3-chlorophenyl)boronic acid, 2-chloro-4,6-diphenyl-1,3,5-triazine and 4-(phenyl-d5)-9H-carbazole were used instead of 1-bromo-3-iodo-2-(methylthio)-benzene, (3-chlorophenyl)boronic acid, 2-chloro-4-phenyl-6-(phenyl-d5)-1,3,5-triazine and 3-phenyl-9H-carbazole, respectively, in Synthesis Example 12.
(Preparation of Second Compound)
5,8-dihydroindolo[2,3-c]carbazole-1,2,3,4,6,7,9,10,11,12-d10 (50 g, 187.7 mmol) and 4-bromo-1,1′-biphenyl-2,3′, 6-d3 (44.3 g, 187.7 mmol) were added to 1000 mL of toluene under a nitrogen atmosphere, and the mixture was stirred and refluxed. Then, sodium tert-butoxide (54.1 g, 563.1 mmol) was added thereto, and sufficiently stirred, followed by adding bis(tri-tertiary-butylphosphine)palladium (2.9 g, 5.6 mmol). After 5 hours of reaction, cooling was performed to room temperature, the organic layer was filtered to remove the salt, and the filtered organic layer was distilled to remove the solvent. Then, this was dissolved again in 793 mL of chloroform corresponding to 10 times (by volume), and washed twice with water. Thereafter, the organic layer was separated, treated with anhydrous magnesium sulfate, stirred, then filtered, and the filtrate was distilled under reduced pressure. The concentrated compound was recrystallized using chloroform and ethyl acetate to prepare Compound 2-1-a in the form of white solid (71.4 g, 90%, MS: [M+H]+=423.6).
The Compound 2-1-a (50 g, 118.3 mmol) and 4-bromo-1,1′-biphenyl-2,3,3′,6-d4 (28.1 g, 118.3 mmol) were added to 1000 mL of toluene under a nitrogen atmosphere, and the mixture was stirred and refluxed. Then, sodium tert-butoxide (34.1 g, 355 mmol) was added thereto, and sufficiently stirred, followed by adding bis(tri-tertiary-butylphosphine)palladium (1.8 g, 3.5 mmol). After 3 hours of reaction, cooling was performed to room temperature, the organic layer was filtered to remove the salt, and the filtered organic layer was distilled to remove the solvent. Then, this was dissolved again in 683 mL of chloroform corresponding to 10 times (by volume), and washed twice with water. Thereafter, the organic layer was separated, treated with anhydrous magnesium sulfate, stirred, then filtered, and the filtrate was distilled under reduced pressure. The concentrated compound was recrystallized using chloroform and ethyl acetate to prepare Compound 2-1 in the form of white solid (41.7 g, 61%, MS: [M+H]+=578.3).
Compound 2-2 (MS: [M+H]+=582.4) was prepared in the same manner as in the preparation of Compound 2-1 in Synthesis Example 16, except that 4-bromo-1,1′-biphenyl-2,3′,5′-d3 and 3-bromo-1,1′-biphenyl-2,2′,3′,4′,5,5′,6,6′-d8 were used instead of 4-bromo-1,1′-biphenyl-2,3′,6-d3 and 4-bromo-1,1′-biphenyl-2,3,3′,6-d4, respectively, in Synthesis Example 16.
Compound 2-3 (MS: [M+H]+=596.4) was prepared in the same manner as in the preparation of Compound 2-1 in Synthesis Example 16, except that 4-bromo-1,1′-biphenyl-2,3′,5,5′-d4 and 4-bromodibenzo[b,d]furan-1,2,3,6,7,8,9-d7 were used instead of 4-bromo-1,1′-biphenyl-2,3′,6-d3 and 4-bromo-1,1′-biphenyl-2,3,3′,6-d4, respectively, in Synthesis Example 16.
Compound 2-4 (MS: [M+H]+=611.4) was prepared in the same manner as in the preparation of Compound 2-1 in Synthesis Example 16, except that 4-bromodibenzo [b, d]thiophene-1,2,3,6,7,8,9-d7 was used instead of 4-bromo-1,1′-biphenyl-2,3,3′,6-d4 in Synthesis Example 16.
Compound 2-5 (MS: [M+H]+=577.4) was prepared in the same manner as in the preparation of Compound 2-1 in Synthesis Example 16, except that 5,7-dihydroindolo[2,3-b]carbazole-2,3,4,6,8,9,10,12-d8, 4-bromo-1,1′-biphenyl-2,3′,5′-d3, and 3-bromo-1,1′-biphenyl-2,3′,5,5′,6-d5 were used instead of 5,8-dihydroindolo[2,3-c]carbazole-1,2,3,4,6,7,9,10,11,12-d10, 4-bromo-1,1′-biphenyl-2,3′,6-d3 and 4-bromo-1,1′-biphenyl-2,3,3′,6-d4, respectively, in Synthesis Example 16.
Compound 2-6 (MS: [M+H]+=687.5) was prepared in the same manner as in the preparation of Compound 2-1 in Synthesis Example 16, except that 5,7-dihydroindolo[2,3-b]carbazole-1,2,3,4,6,8,9,10,11,12-d10, 4-bromo-1,1′-biphenyl-2,2′,3,4′,5′,6-d6, and 1-(4-bromophenyl-2,3,5,6-d4)dibenzo[b,d]-thiophene were used instead of 5,8-dihydroindolo[2,3-c]carbazole-1,2,3,4,6,7,9,10,11,12-d10, 4-bromo-1,1′-biphenyl-2,3′,6-d3 and 4-bromo-1,1′-biphenyl-2,3,3′,6-d4, respectively, in Synthesis Example 16.
Compound 2-7 (MS: [M+H]+=654.3) was prepared in the same manner as in the preparation of Compound 2-1 in Synthesis Example 16, except that 5,11-dihydroindolo[3,2-b]carbazole-2,4,6,8,10,12-d6, 4-bromo-1,1′-biphenyl-2,4′,6-d3, and 5′-bromo-1,1′: 3′,1″-terphenyl-2′,3,3″,4′,5,5″,6′-d7 were used instead of 5,8-dihydroindolo[2,3-c]carbazole-1,2,3,4,6,7,9,10,11,12-d10, 4-bromo-1,1′-biphenyl-2,3′,6-d3 and 4-bromo-1,1′-biphenyl-2,3,3′,6-d4, respectively, in Synthesis Example 16.
Compound 2-8 (MS: [M+H]+=693.3) was prepared in the same manner as in the preparation of Compound 2-1 in Synthesis Example 16, except that 5,11-dihydroindolo[3,2-b]carbazole-2,4,6,8,10,12-d6, 4-bromo-1,1′-biphenyl-2,4′,6-d3, and 2-(4-bromophenyl)-9,9-dimethyl-9H-fluorene-1,3,4,5,6,7,8-d7 were used instead of 5,8-dihydroindolo[2,3-c]carbazole-1,2,3,4,6,7,9,10,11,12-d10, 4-bromo-1,1′-biphenyl-2,3′,6-d3 and 4-bromo-1,1′-biphenyl-2,3,3′,6-d4, respectively, in Synthesis Example 16.
Compound 2-9 (MS: [M+H]+=653.3) was prepared in the same manner as in the preparation of Compound 2-1 in Synthesis Example 16, except that 5,12-dihydroindolo[3,2-a]carbazole-6,7-d2, 3-bromo-1,1′-biphenyl-2,2′,3′,4,4′,5,5′,6,6′-d9, and 3-bromo-1,1′:3′,1″-terphenyl-2″,3″,4″,5″,6″-d5 were used instead of 5,8-dihydroindolo[2,3-c]carbazole-1,2,3,4,6,7,9,10,11,12-d10, 4-bromo-1,1′-biphenyl-2,3′,6-d3 and 4-bromo-1,1′-biphenyl-2,3,3′,6-d4, respectively, in Synthesis Example 16.
Compound 2-10 (MS: [M+H]+=590.3) was prepared in the same manner as in the preparation of Compound 2-1 in Synthesis Example 16, except that 5,12-dihydroindolo[3,2-a]carbazole-2,4,6,7,9,11-d6, 4-bromo-1,1′-biphenyl-2,3′,5′-d3, and 3-bromodibenzo[b,d]furan-1,2,4,7,8,9-d6 were used instead of 5,8-dihydroindolo[2,3-c]carbazole-1,2,3,4,6,7,9,10,11,12-d10, 4-bromo-1,1′-biphenyl-2,3′,6-d3 and 4-bromo-1,1′-biphenyl-2,3,3′,6-d4, respectively, in Synthesis Example 16.
Compound 2-11 (MS: [M+H]+=565.2) was prepared in the same manner as in the preparation of Compound 2-1 in Synthesis Example 16, except that 11,12-dihydroindolo[2,3-a]carbazole-5,6-d2, 4-bromo-1,1′-biphenyl-4′-d, and 4-bromo-1,1′-biphenyl-4′-d were used instead of 5,8-dihydroindolo[2,3-c]carbazole-1,2,3,4,6,7,9,10,11,12-d10, 4-bromo-1,1′-biphenyl-2,3′,6-d3 and 4-bromo-1,1′-biphenyl-2,3,3′,6-d4, respectively, in Synthesis Example 16.
Compound 2-12 (MS: [M+H]+=619.2) was prepared in the same manner as in the preparation of Compound 2-1 in Synthesis Example 16, except that 11,12-dihydroindolo[2,3-a]carbazole-1,2,3,5,6,8,9,10-d8, 4-bromo-1,1′-biphenyl-2,3′,5′-d3, and 2-bromo-9,9-dimethyl-9H-fluorene-1,3,4,5,6,7,8-d7 were used instead of 5,8-dihydroindolo[2,3-c]carbazole-1,2,3,4,6,7,9,10,11,12-d10, 4-bromo-1,1′-biphenyl-2,3′,6-d3 and 4-bromo-1,1′-biphenyl-2,3,3′,6-d4, respectively, in Synthesis Example 16.
A glass substrate on which ITO (Indium Tin Oxide) was coated as a thin film to a thickness of 1400 Å (angstrom) was put into distilled water in which a detergent was dissolved, and ultrasonically cleaned. At this time, a product manufactured by Fischer Co. was used as the detergent, and distilled water filtered twice using a filter manufactured by Millipore Co. was used as the distilled water. After the ITO was cleaned for 30 minutes, ultrasonic cleaning was repeated twice using distilled water for 10 minutes. After the cleaning with distilled water was completed, the substrate was ultrasonically cleaned with solvents of isopropyl alcohol, acetone, and methanol, dried, and then transferred to a plasma cleaner. In addition, the substrate was cleaned for 5 minutes using oxygen plasma and then transferred to a vacuum depositor.
On the prepared ITO transparent electrode, the following Compound HT-A and the following Compound PD were thermally vacuum-deposited to a thickness of 100 Å at a weight ratio of 95:5 to form a hole injection layer. Then, only the following Compound HT-A was deposited to a thickness of 1150 Å to form a hole transport layer. On the hole transport layer, the following Compound HT-B was thermally vacuum-deposited to a thickness of 450 Å to form an electron blocking layer.
On the electron blocking layer, the Compound 1-1 and the Compound 2-1 as a host compound and the following Compound GD as a dopant compound were vacuum-deposited to a thickness of 400 Å at a weight ratio of 85:15 to form a light emitting layer. At this time, a weight ratio of the Compound 1-1 and the Compound 2-1 was 1:1.
On the light emitting layer, the following Compound ET-A was vacuum-deposited to a thickness of 50 Å to form a hole blocking layer. On the hole blocking layer, the following Compound ET-B and the following Compound Liq were thermally vacuum-deposited to a thickness of 250 Å at a weight ratio of 2:1, and then LiF and magnesium were vacuum-deposited to a thickness of 30 Å at a weight ratio of 1:1 to form an electron injection and transport layer. On the electron injection and transport layer, magnesium and silver were deposited to a thickness of 160 Å at a weight ratio of 1:4 to form a cathode, thereby manufacturing an organic light emitting device.
In the above process, the deposition rate of the organic material was maintained at 0.4 Å/sec to 0.7 Å/sec, the deposition rate of lithium fluoride of the cathode was maintained at 0.3 Å/sec, and the deposition rate of silver and aluminum was maintained at 2 Å/sec. In addition, the degree of vacuum during the deposition was maintained at 2×10−7 torr to 5×10−6 torr, thereby manufacturing an organic light emitting device.
An organic light emitting device was manufactured in the same manner as in Example 1, except that the compound of Chemical Formula 1 as a first host and the compound of Chemical Formula 2 as a second host were used by co-deposition at a weight ratio of 1:1 as shown in Table 1 below instead of Compound 1-1 as a first host and Compound 2-1 as a second host in the organic light emitting device of Example 1.
At this time, the structure of the compounds used in Examples is summarized as follows.
An organic light emitting device was manufactured in the same manner as in Example 1, except that the Compound 1-1, Compound 1-2, or Compound 2-1 was used as a single host instead of using the first host and the second host by co-deposition as shown in Table 1 below in the organic light emitting device of Example 1.
An organic light emitting device was manufactured in the same manner as in Example 1, except that the following Compound C1 as a first host and the Compound 2-2 as a second host were used by co-deposition at a weight ratio of 1:1 as shown in Table 1 below in the organic light emitting device of Example 1.
An organic light emitting device was manufactured in the same manner as in Example 1, except that the Compound 1-2, the Compound 1-12, or the following Compound C1 as a first host and the following Compound H1 to H4 as a second host were used by co-deposition at a weight ratio of 1:1 as shown in Table 1 below in the organic light emitting device of Example 1.
At this time, Compounds C1 and H1 to H4 used in Table 1 below are as follows.
For the organic light emitting devices prepared in Examples and Comparative Examples, the voltage, efficiency, and lifespan (T95) were measured by applying a current, and the results are shown in Table 1 below. At this time, the voltage and efficiency were measured by applying a current density of 10 mA/cm2. In addition, T95 means the time (hr) taken until the initial luminance decreases to 95% at a current density of 20 mA/cm2.
As shown in Table 1, the organic light emitting devices of the Examples using both the first compound and the second compound of the present disclosure as a host exhibited superior characteristics in terms of efficiency and lifespan compared to the organic light emitting devices of Comparative Examples 1 to 3 using the first compound or the second compound as a single host, and the organic light emitting devices of Comparative Examples 4 and 11 employing a combination of other hosts instead of the combination of the first compound and the second compound.
Specifically, the organic light emitting devices of Examples 1 to 18 according to the present disclosure had the efficiency improved by about 50% or more, or by about 230% or more in some cases, and the lifespan improved by about 200% or more, compared to the organic light emitting devices of Comparative Examples 1 to 3 using the first compound or the second compound alone. Further, the organic light emitting devices of Examples 1 to 18 according to the present disclosure were greatly improved in both efficiency and lifespan, compared to the organic light emitting device of Comparative Example 4 using the second compound and a compound having a structure different from that of the first compound and the organic light emitting device of Comparative Example 5 using compounds having a structure different from that of the first compound and the second compound. In addition, the organic light emitting devices of Examples 1 to 18 according to the present disclosure had the lifespan improved by about 20% to about 30%, compared to the organic light emitting devices of Comparative Examples 6 to 11 using the first compound and a compound having a structure different from that of the second compound. In particular, the organic light emitting devices of Examples 3 and 14 using Compound 2-2 and Compound 2-4 containing deuterium-substituted indolocarbazole having improved hole transport properties as the second compound, respectively, were very advantageous in balancing charges according to the change of common layers, compared to Comparative Examples 8 and 11 using the conventionally known Compound H4 having a biscarbazole structure as the second host.
Inferred from these results, it can be confirmed that the increase in efficiency and lifespan while maintaining the low driving voltage of the organic light emitting device is because the combination of the compound of Chemical Formula 1 as a first host and the compound of Chemical Formula 2 as a second host facilitates energy transfer to the green dopant in the green light emitting layer. It can be also confirmed that the combination of the compounds of the Examples according to the present disclosure, that is, the combination of the compound of Chemical Formula 1 and the compound of Chemical Formula 2, facilitates electron-hole bonding in a more stable balance to form excitons in the light emitting layer, thereby greatly increasing the efficiency and lifespan. In conclusion, when the compound of Chemical Formula 1 and the compound of Chemical Formula 2 of the present disclosure are combined and co-deposited to be used as a host for the green light emitting layer, it is possible to significantly improve the lifespan while maintaining the low driving voltage and high luminous efficiency of the organic light emitting device.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2021-0051874 | Apr 2021 | KR | national |
This application is a National Stage Application of International Application No. PCT/KR2022/005724 filed on Apr. 21, 2022, which claims the benefit of Korean Patent Application No. 10-2021-0051874 filed on Apr. 21, 2021 in the Korean Intellectual Property Office, the disclosures of which are incorporated herein by reference in their entirety.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/KR2022/005724 | 4/21/2022 | WO |
