Patent Application
20230301183
The present disclosure relates to an organic light emitting device.
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 new materials for the organic materials used in the organic light emitting devices as described above.
(Patent Literature 0001) Korean Unexamined Patent Publication No. 10-2000-0051826
The present disclosure relates to an organic light emitting device.
In the present disclosure, there is provided an organic light emitting device including:
wherein in the Chemical Formula 1:
wherein in the Chemical Formula 2:
wherein in the Chemical Formula 3,
The above-described organic light emitting device can exhibit improved efficiency, driving voltage, and/or lifespan by including two kinds of host compounds in the light emitting layer.
Hereinafter, embodiments of the present disclosure will be described in more detail to facilitate understanding of the invention.
As used herein, the notation
means a bond linked to another substituent group, D means deuterium, and Ph means a phenyl 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 cyano 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 heteroaryl 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. For example, the term “substituted or unsubstituted” can be understood to mean “unsubstituted or substituted with at least one substituent, e.g., 1 to 5 substituents, selected from the group consisting of deuterium, halogen, cyano, C1-10 alkyl, C1-10 alkoxy and C6-20 aryl”. Also, in the present disclosure, the term “substituted with at least one substituent” can be understood to mean “substituted with 1 to 10 substituents”; “substituted with 1 to 5 substituents”; or “substituted with 1 or 2 substituents”.
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. 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-ethylbutyl, pentyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, 1-ethyl-propyl, 1,1-dimethylpropyl, hexyl, n-hexyl, 1-methylpentyl, 2-methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl, 2-ethylbutyl, heptyl, n-heptyl, isohexyl, 1-methylhexyl, 2-methylhexyl, 3-methylhexyl, 4-methylhexyl, 5-methylhexyl, cyclopentylmethyl, cyclohexylmethyl, octyl, n-octyl, tert-octyl, 1-methylheptyl, 2-ethylhexyl, 2,4,4-trimethyl-1-pentyl, 2,4,4-trimethyl-2-pentyl, 2-propylpentyl, n-nonyl, 2,2-dimethylheptyl, 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, adamantyl, 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 anthryl 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, the heteroaryl is heteroaryl 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 heteroaryl 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, the arylamine group, and the arylsilyl 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 group can apply the aforementioned description of the heteroaryl. 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 heteroaryl 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 heteroaryl can be applied, except that the heterocycle is not a monovalent group but formed by combining two substituent groups.
As used herein, the term “deuterated or substituted with deuterium” means that at least one available hydrogen in each Chemical Formula is substituted with deuterium. Specifically, “substituted with deuterium” in the definition of each Chemical Formula or substituent means that at least one or more positions at which hydrogen can be bonded in the molecule are substituted with deuterium. More specifically, it means that at least 10% of the available hydrogen is substituted with deuterium. For example, at least 20%, at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, or 100% are deuterated in each Chemical Formula.
Meanwhile, the organic light emitting device according to an embodiment includes an anode; a cathode that is provided opposite to the anode; and a light emitting layer that is provided between the anode and the cathode, wherein the light emitting layer includes a first compound of Chemical Formula 1, a second compound of Chemical Formula 2 and a third compound of Chemical Formula 3 as host materials of the light emitting layer.
The organic light emitting device according to the present disclosure includes three types of compounds having a specific structure as host materials in the light emitting layer at the same time, thereby improving efficiency, driving voltage, and/or lifespan of the organic light emitting device.
Hereinafter, the present invention will be described in detail for each configuration.
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.
The organic light emitting device according to the present disclosure can include a hole injection layer between an anode and a hole transport layer to be described later, if necessary.
The hole injection layer located on the anode is a layer for injecting holes from the anode, and includes a hole injection material. 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 porphyrine, 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.
The organic light emitting device according to the present disclosure can include a hole transport layer between an anode and a light emitting layer. The hole transport layer is a layer that receives holes from an anode or a hole injection layer formed on the anode and transports the holes to the light emitting layer, and includes a hole transport material. 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 thereof 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.
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.
The organic light emitting device according to the present disclosure can include a light emitting layer between an anode and a cathode, and the light emitting layer includes the first compound, the second compound and the third compound as host materials. Specifically, the first compound and the second compound function as a P-type host material having a hole transport ability superior to an electron transport ability, and the third compound functions as an N-type host material having an electron transport ability superior to a hole transport ability, thereby maintaining the ratio of holes to electrons in the light emitting layer. In particular, when the above two types of compounds are used as the P-type host material, low voltage and long lifespan can be exhibited compared to the case where only one type of compound is used. In addition, the device including the above three types of host materials can exhibit high efficiency and long lifespan compared to devices including a combination of other compounds.
Hereinafter, the first compound, the second compound and the third compound will be described.
The first compound is the following Chemical Formula 1. Specifically, the first compound is an indolocarbazole compound, can efficiently transfer holes to a dopant material, and thus can increase the probability of hole-electron recombination in the light emitting layer together with a third compound to be described later having excellent electron transport ability.
The first compound can be represented by any one of the following Chemical Formulae 1-1 to 1-5, depending on the fused position of A:
wherein in the Chemical Formulae 1-1 to 1-5:
In addition, in the Chemical Formula 1, L1 and L2 can each independently be a single bond, or unsubstituted or deuterium-substituted C6-20 arylene.
Specifically, L1 and L2 can each independently be a single bond, or phenylene.
More specifically, L1 and L2 can each independently be a single bond, 1,2-phenylene, 1,3-phenylene, or 1,4-phenylene. For example, both of L1 and L2 are a single bond; or one of L1 and L2 is a single bond, and the other is 1,3-phenylene, or 1,4-phenylene.
In addition, Ar1 and Ar2 can each independently be C6-20 aryl which is unsubstituted or substituted with at least one substituent selected from the group consisting of deuterium, C1-10 alkyl and C6-20 aryl; or C2-20 heteroaryl containing one heteroatom of N, O and S which is unsubstituted or substituted with at least one substituent selected from the group consisting of deuterium, C1-10 alkyl and C6-20 aryl.
Specifically, both of Ar1 and Ar2 can be C6-20 aryl which is unsubstituted or substituted with one or two substituents selected from the group consisting of deuterium, and C1-10 alkyl; or one of Ar1 and Ar2 can be C6-20 aryl which is unsubstituted or substituted with one or two substituents selected from the group consisting of deuterium, and C1-10 alkyl, and the other can be C2-20 heteroaryl containing one heteroatom of N, O and S which is unsubstituted or substituted with deuterium.
More specifically, Ar1 and Ar2 can each independently be phenyl, biphenylyl, terphenylyl, naphthyl, fluorenyl, dibenzofuranyl, or dibenzothiophenyl, and
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.
In other words, Ar1 and Ar2 may not include a 6-membered heterocyclic ring containing N heteroatom.
For example, Ar1 and Ar2 can be any one selected from the group consisting of the following, but are not limited thereto:
Herein, Ar1 and Ar2 can be the same as or different from each other.
In addition, all of R1 to R3 can be hydrogen or deuterium.
Herein, a representing the number of R1 is 0, 1, 2, 3, or 4, b representing the number of R2 is 0, 1, or 2, and c representing the number of R3 is 0, 1, 2, 3, or 4.
Representative examples of the first compound of Chemical Formula 1 are as follows:
Meanwhile, the first compound can be prepared by, for example, a preparation method as shown in Reaction Scheme 1 below.
wherein in the Reaction Scheme 1, each X is independently halogen, preferably bromo, or chloro, and the definitions of other substituents are the same as described above.
Specifically, the compound of Chemical Formula 1 is prepared by combining starting materials of SM1 and SM2 through an amine substitution reaction. Such an amine substitution reaction is preferably performed in the presence of a palladium catalyst and a base. In addition, the reactive group for the amine substitution reaction can be appropriately changed, and the method for preparing the compound of Chemical Formula 1 can be more specifically described in Preparation Examples described below.
The second compound is a biscarbazole-based compound of the following Chemical Formula 2, and acts as a P-type host like the first compound. Accordingly, it can efficiently transfer holes in the light emitting layer, and thus can increase the probability of hole-electron recombination in the light emitting layer together with a third compound to be described later having excellent electron transport ability.
In compound of Chemical Formula 2, the bonding positions of two carbazole structures are as follows:
wherein in the Chemical Formula 2:
the description of each substituent is the same as described above, and
a single bond connecting the two carbazole structures can be connected
to one of the carbon at position *1, the carbon at position *2, the carbon at position *3, and the carbon at position *4 of the left carbazole structure, and
one of the carbon at position *1′, the carbon at position *2′, the carbon at position *3′, and the carbon at position *4′ of the right carbazole structure.
More specifically, the second compound can be a compound in which (carbon at position *1, carbon at position *1′), (carbon at position *2, carbon at position *2′), (carbon at position *3, carbon at position *3′), or (carbon at position *4, carbon at position *4′) in the left carbazole structure and the right carbazole structure are linked and bonded to each other.
According to one embodiment, the second compound can be the following Chemical Formula 2-1 having a structure in which (carbon at position *3 of the left carbazole structure, carbon at position *3′ of the right carbazole structure) are bonded to each other:
wherein in the Chemical Formula 2-1:
In addition, Ar11 and Ar12 can each independently be C6-20 aryl which is unsubstituted or substituted with at least one substituent selected from the group consisting of deuterium, C1-10 alkyl and C6-20 aryl; or C2-20 heteroaryl containing at least one heteroatom of N, O and S which is unsubstituted or substituted with at least one substituent selected from the group consisting of deuterium, C1-10 alkyl and C6-20 aryl.
Specifically, both of Ar11 and Ar12 can be C6-20 aryl which is unsubstituted or substituted with one or two substituents selected from the group consisting of deuterium, and C1-10 alkyl; or one of Ar11 and Ar12 can be C6-20 aryl which is unsubstituted or substituted with one or two substituents selected from the group consisting of deuterium, and C1-10 alkyl, and the other can be C2-20 heteroaryl containing at least one heteroatom of N, O and S which is unsubstituted or substituted with deuterium.
More specifically, Ar11 and Ar12 can each independently be phenyl, biphenylyl, terphenylyl, naphthyl, fluorenyl, dibenzofuranyl, or dibenzothiophenyl, and
Ar11 and Ar12 can be unsubstituted or substituted with at least one substituent selected from the group consisting of deuterium, C1-10 alkyl and C6-20 aryl.
In other words, Ar11 and Ar12 may not include a 6-membered heterocyclic ring containing N heteroatom.
For example, Ar11 and Ar12 can be any one selected from the group consisting of the following, but are not limited thereto:
wherein,
Herein, at least one of Ar11 and Ar12 can be phenyl or biphenylyl.
In addition, Ar11 and Ar12 can be the same as or different from each other.
In addition, in the Chemical Formula 2, R11 and R12 can each independently be hydrogen, deuterium, or C6-20 aryl which is unsubstituted or substituted with deuterium.
For example, R11 and R12 can each independently be hydrogen, deuterium, or phenyl, but the present disclosure is not limited thereto.
In addition, d and e, each representing the number of R11 and R12, can independently be 0, 1, 2, 3, 4, 5, 6, or 7.
More specifically, d and e can each independently be 0, 1, or 7.
For example, d+e can be 0 or 1.
Representative examples of the second compound of Chemical Formula 2 are as follows:
Meanwhile, the second compound can be prepared by, for example, a preparation method as shown in Reaction Scheme 2 below.
in the Reaction Scheme 2, each X is independently halogen, preferably bromo, or chloro, and the definitions of other substituents are the same as described above.
Specifically, the compound of Chemical Formula 2 is prepared by combining starting materials of SM3 and SM4 through an amine substitution reaction. Such an amine substitution reaction is preferably performed in the presence of a palladium catalyst and a base. In addition, the reactive group for the amine substitution reaction can be appropriately changed, and the method for preparing the compound of Chemical Formula 2 can be more specifically described in Preparation Examples described below.
The compound has a structure in which an N-containing 6-membered heterocyclic ring is substituted in one benzene ring of dibenzofuran/dibenzothiophene core and one aryl/heteroaryl group is substituted in the other benzene ring. The third compound has superior electron transport ability compared to i) a compound in which an N-containing 6-membered heterocyclic ring is substituted in one benzene ring of the dibenzofuran/dibenzothiophene core, but the other benzene ring does not have a substituent other than deuterium, and ii) a compound in which an N-containing 6-membered heterocyclic ring and an aryl/heteroaryl group are simultaneously substituted in one benzene ring of the dibenzofuran/dibenzothiophene core, so that electrons are efficiently transferred to a dopant material, thereby increasing the probability of electron-hole recombination in the light emitting layer.
In the Chemical Formula 3, all of X1 to X3 are N; or two of X1 to X3 are N, and the other is CH.
In addition, L can be a single bond.
In addition, Ar21 can be C6-20 aryl which is unsubstituted or substituted with deuterium.
Alternatively, Ar21 can be C2-20 heteroaryl containing O or S heteroatom which is unsubstituted or substituted with deuterium.
Alternatively, Ar21 can be C2-20 heteroaryl containing one or two N heteroatoms which is unsubstituted or substituted with at least one substituent selected from the group consisting of deuterium, phenyl and deuterium-substituted phenyl.
Specifically, Ar21 can be represented by any one of the following Chemical Formulae 4a to 4t:
in the Chemical Formulae 4a to 4t,
Herein, n1 is 0, or 5,
In addition, when Ar21 is C6-20 aryl which is unsubstituted or substituted with deuterium, Ar21 can be any one of Chemical Formulae 4a to 4j.
In addition, when Ar21 is C2-20 heteroaryl containing O or S heteroatom which is unsubstituted or substituted with deuterium, Ar21 can be any one of Chemical Formula 4s or 4t.
In addition, when Ar21 is C2-20 heteroaryl containing one or two N heteroatoms which is unsubstituted or substituted with at least one substituent selected from the group consisting of deuterium, phenyl and deuterium-substituted phenyl, Ar21 can be any one of Chemical Formulae 4k to 4r.
In addition, Ar22 and Ar23 can each independently be C6-20 aryl which is unsubstituted or substituted with at least one substituent selected from the group consisting of deuterium, C1-10 alkyl, and unsubstituted or deuterium-substituted C6-20 aryl; or C2-20 heteroaryl containing one heteroatom of N, O and S which is unsubstituted or substituted with at least one substituent selected from the group consisting of deuterium, C1-10 alkyl, and unsubstituted or deuterium-substituted C6-20 aryl.
However, when one of Ar22 and Ar23 is dibenzofuranyl, the other can be neither dibenzofuranyl nor dibenzothiophenyl, and when one of Ar22 and Ar23 is dibenzothiophenyl, the other can be neither dibenzofuranyl nor dibenzothiophenyl.
Specifically, Ar22 and Ar23 are each independently phenyl, biphenylyl, terphenylyl, naphthyl, fluorenyl, dibenzofuranyl, dibenzothiophenyl, or carbazolyl, and
Ar22 and Ar23 can be unsubstituted or substituted with at least one substituent selected from the group consisting of deuterium, C1-10 alkyl, and unsubstituted or deuterium-substituted C6-20 aryl, for example, selected from the group consisting of deuterium, methyl, phenyl and deuterium-substituted phenyl.
For example, Ar22 and Ar23 can each independently be any one selected from the group consisting of the following, but are not limited thereto:
Herein, at least one of Ar22 and Ar23 can be
In addition, Ar22 and Ar23 can be the same as or different from each other.
In addition, in the Chemical Formula 3, f representing the number of R21 can be 0, 1, 2, 3, 4, 5, or 6.
In addition, R21 can be deuterium, and when f is 0, at least one of Ar21 to Ar23 can be substituted with deuterium.
Meanwhile, the third compound can be the following Chemical Formula 3-1:
wherein in Chemical Formula 3-1:
Alternatively, the third compound can be the following Chemical Formula 3-2:
wherein in the Chemical Formula 3-2:
Alternatively, the third compound can be the following Chemical Formula 3-3:
wherein in the Chemical Formula 3-3:
Alternatively, the third compound can be the following Chemical Formula 3-4:
wherein in the Chemical Formula 3-4:
Representative examples of the third compound of Chemical Formula 3 are as follows:
Meanwhile, the third compound can be prepared by, for example, a preparation method as shown in Reaction Scheme 3 below.
wherein in the Reaction Scheme 3, each X is independently halogen, preferably bromo, or chloro, and the definitions of other substituents are the same as described above.
Specifically, the compound of Chemical Formula 3 is prepared by combining starting materials of SM5 and SM6 through the Suzuki-coupling reaction. The Suzuki-coupling reaction is preferably performed in the presence of a palladium catalyst and a base. In addition, the reactive group for the Suzuki-coupling reaction can be appropriately changed, and the method for preparing the compound of Chemical Formula 3 can be more specifically described in Preparation Examples described below.
Also, in one embodiment, at least one of the first compound, the second compound, and the third compound can contain deuterium in the compound. More specifically, the second compound can contain deuterium; the third compound can contain deuterium; or the second compound and the third compound can contain deuterium at the same time. In this case, deuterium (D) contained in the compound in the light emitting layer lowers vibration energy in the radical anion state of the deuterium-containing compound, and accordingly, the compound can have stable energy, and the formed exciplex can also be in a more stable state.
Meanwhile, a ratio of (total weight of first compound and second compound) to (weight of third compound) can be 90:10 to 10:90 in the light emitting layer. More specifically, the ratio of (total weight of first compound and second compound) to (weight of third compound) can be 90:10 to 50:50, or 85:15 to 75:25 in the light emitting layer. Preferably, the ratio of (total weight of first compound and second compound) to (weight of third compound) can be 80:20 in the light emitting layer.
In other words, the third compound can be included in the light emitting layer in an amount of 10 wt % to 50 wt % based on a total weight of the first compound, the second compound, and the third compound. When the third compound is included in an amount of less than 10 wt % based on the total weight of the first compound, the second compound, and the third compound, electron transport in the light emitting layer is not smooth, so that holes and electrons are not balanced throughout the device, resulting in problems in voltage, efficiency, and lifespan of the manufactured device. When the third compound is included in an amount exceeding 50 wt %, there can be a problem in that lifespan of the device is lowered.
For example, the third compound can be included in the light emitting layer in an amount of 10 wt % or more, or 15 wt % or more, and 40 wt % or less, 30 wt % or less, or 25 wt % or less based on the total weight of the first compound, the second compound, and the third compound.
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 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 driving voltage is increased, and when the second compound is included in an excessive amount, there can be a problem in that efficiency is lowered. For example, a weight ratio of the first compound to the second compound in the light emitting layer can be 2:8 to 8:2, 2.5:7.5 to 7:3, 2.5:7.5 to 6:4, or 2.5:7.5 to 5:5. Preferably, the second compound can be included in the light emitting layer in an amount equal to or greater than that of the first compound.
Meanwhile, the light emitting layer can further include a dopant material other than the three 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.
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 and the dopant material.
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 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 an hole blocking material, and as an example of such an hole blocking material, compounds having introduced electron attracting groups, such as azine-based derivatives including triazine; triazole derivatives; oxadiazole derivatives; phenanthroline derivatives; phosphine oxide derivatives can be used, but is not limited thereto.
The electron transport layer is formed between the light emitting layer and the cathode to receive electrons from an electron injection layer and transport 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 injection and transport material include: an Al 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 organic light emitting device according to the present disclosure can include an electron injection layer between an electron transport layer and a cathode, if necessary.
The electron injection layer is located between the electron transport layer and a cathode, and injects electrons from the cathode. The electron injection layer includes an electron injection material, and a material capable of transporting electrons, having an excellent effect of injecting electrons to a light emitting layer or a light emitting material, and excellent in forming a thin film is suitable.
Specific examples of the electron injection material include LiF, NaCl, CsF, Li2O, BaO, fluorenone, anthraquinodimethane, diphenoquinone, thiopyran dioxide, oxazole, oxadiazole, triazole, imidazole, perylenetetracarboxylic acid, fluorenylidene methane, anthrone, and the like, and derivatives thereof, a metal complex compound, a nitrogen-containing 5-membered ring derivative, and the like, but are not limited thereto.
Examples of the metal complex compound include 8-hydroxyquinolinato lithium, bis(8-hydroxyquinolinato)zinc, bis(8-hydroxy-quinolinato)copper, bis(8-hydroxyquinolinato)manganese, tris(8-hydroxy-quinolinato)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.
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-mentioned 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 a cathode material, an organic material layer and an anode material on a substrate. 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.
Meanwhile, the organic light emitting device according to the present disclosure can be a front side emission type, a backside emission type, or a double-sided emission type according to the used material.
The preparation of the organic light emitting device will be described in detail in the following examples. However, these examples are presented for illustrative purposes only, and are not intended to limit the scope of the present disclosure.
11,12-dihydroindolo[2,3-a]carbazole (15.0 g, 58.5 mmol) and 4-bromo-1,1′-biphenyl (30.0 g, 128.8 mmol) were added to toluene (300 ml) under a nitrogen atmosphere, and the mixture was stirred and refluxed. Then, sodium tert-butoxide (16.9 g, 175.6 mmol) and bis(tri-tert-butylphosphine)palladium(0) (0.9 g, 1.8 mmol) were added thereto. After 12 hours of reaction, it was cooled to room temperature and the organic layer was separated using chloroform and water, and then the organic layer was distilled. Then, this was dissolved again in chloroform, 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 purified by silica gel column chromatography, and then 9.8 g of Compound 1-1 was prepared through sublimation purification (yield 30%, MS: [M+H]+=562).
11,12-dihydroindolo[2,3-a]carbazole (15.0 g, 58.5 mmol) and 5′-bromo-1,1′:3,1″-terphenyl (19.9 g, 64.4 mmol) were added to toluene (300 ml) under a nitrogen atmosphere, and the mixture was stirred and refluxed. Then, sodium tert-butoxide (8.4 g, 87.8 mmol) and bis(tri-tert-butylphosphine)palladium(0) (0.9 g, 1.8 mmol) were added thereto. After 11 hours of reaction, it was cooled to room temperature and the organic layer was separated using chloroform and water, and then the organic layer was distilled. Then, this was dissolved again in chloroform, 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 purified by silica gel column chromatography to prepare 19.3 g of Intermediate 1-2-1 (yield 68%, MS: [M+H]+=486).
Intermediate 1-2-1 (15.0 g, 31.0 mmol) and 4-bromo-1,1′-biphenyl (7.9 g, 34.0 mmol) were added to toluene (300 ml) under a nitrogen atmosphere, and the mixture was stirred and refluxed. Then, sodium tert-butoxide (4.5 g, 46.4 mmol) and bis(tri-tert-butylphosphine)palladium(0) (0.5 g, 0.9 mmol) were added thereto. After 7 hours of reaction, it was cooled to room temperature and the organic layer was separated using chloroform and water, and then the organic layer was distilled. Then, this was dissolved again in chloroform, 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 purified by silica gel column chromatography, and then 9.5 g of Compound 1-2 was prepared through sublimation purification (yield 48%, MS: [M+H]+=638).
Compound 1-3 was prepared in the same manner as in the preparation method of Compound 1-2, except that 5,8-dihydroindolo[2,3-c]carbazole was changed to 5,11-dihydroindolo[3,2-b]carbazole, 5′-bromo-1,1′:3′,1″-terphenyl was changed to 4-bromo-1,1′-biphenyl, and 4-bromo-1,1′-biphenyl was changed to 4-chloro-1,1′:3′,1″-terphenyl in Preparation Example 1-2 (MS: [M+H]+=638).
Compound 1-4 was prepared in the same manner as in the preparation method of Compound 1-2, except that 5,8-dihydroindolo[2,3-c]carbazole was changed to 5,12-dihydroindolo[3,2-a]carbazole, and 5′-bromo-1,1′:3′,1″-terphenyl′ was changed to 2-bromodibenzo[b,d]furan in Preparation Example 1-2 (MS: [M+H]+=576).
Compound 1-5 was prepared in the same manner as in the preparation method of Compound 1-2, except that 5′-bromo-1,1′:3′,1″-terphenyl′ was changed to 4-bromo-1,1′-biphenyl and 4-bromo-1,1′-biphenyl was changed to 3-bromo-1,1′-biphenyl in Preparation Example 1-2 (MS: [M+H]+=562).
Compound 1-6 was prepared in the same manner as in the preparation method of Compound 1-2, except that 5′-bromo-1,1′:3′,1″-terphenyl′ was changed to 4-bromo-1,1′-biphenyl and 4-bromo-1,1′-biphenyl was changed to 4-chloro-1,1′:3′,1″-terphenyl in Preparation Example 1-2 (MS: [M+H]+=638).
3-bromo-9H-carbazole (15.0 g, 60.9 mmol) and 9-phenyl-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolane-2-yl)-9H-carbazole (24.8 g, 67.0 mmol) were added to 300 ml of THF under a nitrogen atmosphere, and the mixture was stirred and refluxed. Then, potassium carbonate (33.7 g, 243.8 mmol) was dissolved in water (101 ml), and then added thereto. Thereafter, it was stirred sufficiently, followed by adding tetrakis(triphenylphosphine)palladium(0) (2.1 g, 1.8 mmol). After 10 hours of reaction, it was cooled to room temperature and the organic layer was separated from the water layer, and then the organic layer was distilled. Then, this was dissolved again in chloroform, 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 purified by silica gel column chromatography to prepare 15.2 g of Compound 2-1-1 (yield 61%, MS: [M+H]+=410).
Compound 2-1-1 (15.0 g, 36.7 mmol) and 4-bromo-1,1′-biphenyl (9.4 g, 40.4 mmol) were added to toluene (300 ml) under a nitrogen atmosphere, and the mixture was stirred and refluxed. Then, sodium tert-butoxide (5.3 g, 55.1 mmol) and bis(tri-tert-butylphosphine)palladium(0) (0.6 g, 1.1 mmol) were added thereto. After 10 hours of reaction, it was cooled to room temperature and the organic layer was separated using chloroform and water, and then the organic layer was distilled. Then, this was dissolved again in chloroform, 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 purified by silica gel column chromatography, and then 9.7 g of Compound 2-1 was prepared through sublimation purification (yield 47%, MS: [M+H]+=561).
Compound 2-2 was prepared in the same manner as in the preparation method of Compound 2-1, except that 9-phenyl-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-9H-carbazole was changed to 9-([1,1′-biphenyl]-3-yl)-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-9H-carbazole and 4-bromo-1,1′-biphenyl was changed to 3-bromo-1,1′-biphenyl in Preparation Example 2-1 (MS: [M+H]+=637).
Compound 2-3 was prepared in the same manner as in the preparation method of Compound 2-1, except that 4-bromo-1,1′-biphenyl was changed to 2-bromodibenzo[b, d]furan in step 2 of Preparation Example 2-1 (MS: [M+H]+=576).
Compound 2-4 was prepared in the same manner as in the preparation method of Compound 2-1, except that 4-bromo-1,1′-biphenyl was changed to 2-chloro-9,9-dimethyl-9H-fluorene in Preparation Example 2-1 (MS: [M+H]+=602).
Compound 2-5 was prepared in the same manner as in the preparation method of Compound 2-1, except that Compound 2-1-1 was changed to Compound 2-2-1 in step 2 of Preparation Example 2-1 (MS: [M+H]+=637).
After dispersing 9-(1,1′-biphenyl)-4-yl)-3-bromo-9H-carbazole (15 g, 37.7 mmol) and 9-([1,1′-biphenyl]-4-yl)-9H-carbazol-3-yl)boronic acid (13.7 g, 37.7 mmol) in tetrahydrofuran (300 mL), 2M aqueous potassium carbonate solution (aq. K2CO3, 100 mL, 75.3 mmol) was added thereto. Then, tetrakistriphenylphosphinepalladium [Pd(PPh3)4](0.4 g, 1 mol %) was added thereto, and the mixture was stirred and refluxed for 3 hours. Thereafter, it was cooled to room temperature and the water layer was removed, followed by concentration under reduced pressure. Then, ethyl acetate was added, stirred under reflux for 1 hour, cooled to room temperature, and the solid was filtered. The resulting solid was dissolved in chloroform under reflux, and ethyl acetate was added to prepare Compound 2-6 by recrystallization (13.5 g, yield 56%, MS:[M+H]+=637).
Compound 2-7 was prepared in the same manner as in the preparation method of Compound 2-6, except that 9-(1,1′-biphenyl)-4-yl)-3-bromo-9H-carbazole was changed to 9-([1,1′-biphenyl]-2-yl)-3-bromo-9H-carbazole in Preparation Example 2-6 (MS: [M+H]+=637).
Compound 2-1 (20 g, 31.41 mmol) was added to 200 mL of Benzen-D6 under a nitrogen atmosphere, and the mixture was stirred. Thereafter, triflic acid (3.4 g, 22.65 mmol) was added thereto, and the mixture was heated and stirred. After 4 hours of reaction, it was cooled to room temperature, and ethanol was added thereto, followed by filtration of the resulting solid. The solid was dissolved in 886 mL of chloroform corresponding to 30 times, 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 purified by silica column using chloroform and ethyl acetate to prepare Compound 2-8 in the form of white solid (13.2 g, 64%, MS: [M+H]+=578.8).
Compound 2-9 was prepared in the same manner as in the preparation method of Compound 2-8, except that Compound 2-1 was changed to Compound 2-2 in Preparation Example 2-8 (MS: [M+H]+=656).
9-([1,1′-biphenyl]-3-yl)-9′-(4-chlorophenyl)-9H,9′H-3,3′-bicarbazole (15 g, 25.2 mmol) and (phenyl-d5)boronic acid (3.2 g, 25.2 mmol) were added to 300 mL of dioxin under a nitrogen atmosphere, and the mixture was stirred and refluxed. Thereafter, potassium triphosphate (16.1 g, 75.6 mmol) was dissolved in 16 mL of water, and sufficiently stirred, followed by adding dibenzylideneacetonepalladium (0.4 g, 0.8 mmol) and tricyclohexylphosphine (0.4 g, 1.5 mmol). After 9 hours of reaction, it was cooled to room temperature, and the resulting solid was filtered. The solid was dissolved in 485 mL of dichlorobenzene (DCB) corresponding to 30 times, 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 DCB and ethyl acetate to prepare Compound 2-10 in the form of white solid (9.9 g, 61%, MS: [M+H]+=642.8).
1-bromo-3-fluoro-2-iodobenzene (75 g, 249.3 mmol), and (5-chloro-2-methoxyphenyl) boronic acid (51.1 g, 249.3 mmol) were dissolved in 550 mL of tetra hydrofuran. 2M sodium carbonate (Na2CO3) solution (350 mL) and tetrakis(triphenylphosphine)palladium(0) (2.88 g, 2.49 mmol) were added thereto, and the mixture was refluxed for 11 hours. After the reaction, it was cooled to room temperature, and the water layer was separated to remove. After drying with anhydrous magnesium sulfate, the mixture was concentrated under reduced pressure and then recrystallized using chloroform and ethanol to obtain Compound A-1 (63.2 g, yield 80%; MS: [M+H]+=314).
Compound A-1 (63.2 g, 200.3 mmol) was dissolved in 750 mL of dichloromethane, and then cooled to 0° C. Boron tribromide (20.0 mL, 210.3 mmol) was slowly added dropwise thereto, followed by stirring for 12 hours. After completion of the reaction, it was washed with water three times, dried with magnesium sulfate, and filtered. The filtrate was distilled under reduced pressure and purified by column chromatography to obtain Compound A-2 (57.9 g, yield 96%; MS:[M+H]+=300).
Compound A-2 (57.9 g, 192.0 mmol) and calcium carbonate (79.6 g, 576.0 mol) were dissolved in 350 mL of N-methyl-2-pyrrolidone, followed by heating and stirring for 2 hours. After lowering the temperature to room temperature, it was filtered by reverse precipitation in water. Then, it was completely dissolved in dichloromethane and washed with water. Thereafter, it was dried with anhydrous magnesium sulfate, concentrated under reduced pressure, and dried by recrystallization using ethanol to obtain Compound A-3 (42.1 g, yield 78%; MS:[M+H]+=280).
After dissolving Compound A-3 (42.1 g, 149.5 mmol) in tetrahydrofuran (330 mL), the temperature was lowered to −78° C., and 2.5 M tert-butyllithium (t-BuLi, 60.4 mL, 151.0 mmol) was slowly added thereto. After stirring at the same temperature for 1 hour, triisopropyl borate (51.8 mL, 224.3 mmol) was added, and the mixture was stirred for 3 hours while slowly raising the temperature to room temperature. 2 N hydrochloric acid (300 mL) was added to the reaction mixture and stirred at room temperature for 1.5 hours. The resulting precipitate was filtered, washed sequentially with water and ethyl ether, and then vacuum-dried to prepare Intermediate A-4 (34.3 g, yield 93%; MS:[M+H]+=247).
After dissolving 1-bromo-3-chloro-2-methoxybenzene (100.0 g, 451.5 mmol) in tetrahydrofuran (1000 mL), the temperature was lowered to −78° C., and 2.5 M tert-butyllithium (t-BuLi, 182.4 mL, 456.0 mmol) was slowly added thereto. After stirring at the same temperature for 1 hour, triisopropyl borate (B(OiPr)3, 156.3 mL, 677.3 mmol) was added, and the mixture was stirred for 3 hours while slowly raising the temperature to room temperature. 2 N hydrochloric acid (150 mL) was added to the reaction mixture and stirred at room temperature for 1.5 hours. The resulting precipitate was filtered, washed sequentially with water and ethyl ether, and then vacuum-dried. Thereafter, it was recrystallized using chloroform and ethyl acetate, and dried to prepare Compound B-1 (84.2 g, yield 90%; MS:[M+H]+=230).
Compound B-2 (74.6 g, yield 52%; MS:[M+H]+=314) was prepared in the same manner as in the preparation method of Compound A-1 of Preparation Example 3-1, except that Compound B-1 (84.2 g, 451.7 mmol) was used instead of (5-chloro-2-methoxyphenyl) boronic acid.
Compound B-3 (60.3 g, yield 85%; MS:[M+H]+=300) was prepared in the same manner as in the preparation method of Compound A-2, except that Compound B-2 (74.6 g, 236.4 mmol) was used instead of Compound A-1.
Compound B-4 (48.1 g, yield 85%; MS:[M+H]+=280) was prepared in the same manner as in the preparation method of Compound A-3, except that Compound B-3 (60.3 g, 199.9 mmol) was used instead of Compound A-2.
Compound B-5 (40.1 g, yield 95%; MS:[M+H]+=247) was prepared in the same manner as in the preparation method of Compound A-4, except that Compound B-3 (48.1 g, 170.9 mmol) was used instead of Compound A-3.
Compound C-1 (60.1 g, yield 76%; MS:[M+H]+=314) was prepared in the same manner as in the preparation method of Compound A-1 of Preparation Example 1, except that (4-chloro-2-methoxyphenyl) boronic acid (51.1 g, 249.3 mmol) was used instead of (5-chloro-2-methoxyphenyl) boronic acid.
Compound C-2 (54.0 g, yield 94%; MS:[M+H]+=300) was prepared in the same manner as in the preparation method of Compound A-2, except that Compound C-1 (60.1 g, 190.4 mmol) was used instead of Compound A-1.
Compound C-3 (42.2 g, yield 83%; MS:[M+H]+=280) was prepared in the same manner as in the preparation method of Compound A-3, except that Compound C-2 (54.0 g, 179.1 mmol) was used instead of Compound A-2.
Compound C-4 (34.1 g, yield 92%; MS:[M+H]+=247) was prepared in the same manner as in the preparation method of Compound A-4, except that Compound C-3 (42.2 g, 170.9 mmol) was used instead of Compound A-3.
Compound D-1 (63.5 g, yield 81%; MS:[M+H]+=314) was prepared in the same manner as in the preparation method of Compound A-1 of Preparation Example 1, except that (2-chloro-6-methoxyphenyl) boronic acid (51.1 g, 249.3 mmol) was used instead of (5-chloro-2-methoxyphenyl) boronic acid.
Compound D-2 (55.1 g, yield 91%; MS:[M+H]+=300) was prepared in the same manner as in the preparation method of Compound A-2, except that Compound D-1 (63.5 g, 201.2 mmol) was used instead of Compound A-1.
Compound D-3 (42.0 g, yield 82%; MS:[M+H]+=280) was prepared in the same manner as in the preparation method of Compound A-3, except that Compound C-2 (55.1 g, 182.7 mmol) was used instead of Compound A-2.
Compound D-4 (35.7 g, yield 85%; MS:[M+H]+=247) was prepared in the same manner as in the preparation method of Compound A-4, except that Compound C-3 (42.0 g, 149.2 mmol) was used instead of Compound A-3.
Compound E-4 (MS: [M+H]+=247) was prepared in the same manner as in the preparation method of Compound 3-1, except that 1-bromo-3-fluoro-2-iodobenzene was changed to 4-bromo-2-fluoro-1-iodobenzene in Preparation Example 3-1.
Compound F-4 (MS: [M+H]+=247) was prepared in the same manner as in the preparation method of Compound 3-1, except that 1-bromo-3-fluoro-2-iodobenzene was changed to 4-bromo-1-fluoro-2-iodobenzene in Preparation Example 3-1.
Compound G-4 (MS: [M+H]+=247) was prepared in the same manner as in the preparation method of Compound 3-1, except that 1-bromo-3-fluoro-2-iodobenzene was changed to 1-bromo-2-fluoro-3-iodobenzene and (5-chloro-2-methoxyphenyl)boronic acid was changed to (4-chloro-2-methoxyphenyl)boronic acid in Preparation Example 3-1.
Compound H-4 (MS: [M+H]+=247) was prepared in the same manner as in the preparation method of Compound 3-1, except that 1-bromo-3-fluoro-2-iodobenzene was changed to 4-bromo-2-fluoro-1-iodobenzene and (5-chloro-2-methoxyphenyl)boronic acid was changed to (4-chloro-2-methoxyphenyl)boronic acid in Preparation Example 3-1.
Compound 1-5 (MS: [M+H]+=247) was prepared in the same manner as in the preparation method of Compound 3-1, except that 1-bromo-3-fluoro-2-iodobenzene was changed to 1-bromo-2-fluoro-3-iodobenzene and (5-chloro-2-methoxyphenyl)boronic acid was changed to Compound 1-1 prepared in the same manner as in the preparation method of Compound 3-2 in Preparation Example 3-1.
Compound J-4 (MS: [M+H]+=247) was prepared in the same manner as in the preparation method of Compound 3-1, except that 1-bromo-3-fluoro-2-iodobenzene was changed to 1-bromo-2-fluoro-3-iodobenzene in Preparation Example 3-1.
A-4 (20 g, 81.2 mmol) and 2-chloro-4-phenyl-6-(phenyl-d5)-1,3,5-triazine (22.1 g, 81.2 mmol) were added to 500 ml of tetrahydrofuran under a nitrogen atmosphere, and the mixture was stirred and refluxed. Then, potassium carbonate (33.6 g, 243.5 mmol) was dissolved in 34 ml of water, and then added thereto. Thereafter, it was stirred sufficiently, followed by adding bis(tri-tert-butylphosphine)palladium (1.2 g, 2.4 mmol). After 7 hours of reaction, it was cooled to room temperature and the resulting solid was filtered. The solid was dissolved in 1781 mL of tetrahydrofuran, 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 tetrahydrofuran and ethyl acetate to prepare Compound 3-1-1 in the form of white solid (27.4 g, 77%, MS: [M+H]+=439.9).
3-1-1 (10 g, 22.8 mmol) and triphenylen-2-ylboronic acid (6.2 g, 22.8 mmol) were added to 200 ml of Diox under a nitrogen atmosphere, and the mixture was stirred and refluxed. Then, potassium triphosphate (14.5 g, 68.3 mmol) was dissolved in water (15 ml), and then added thereto. Thereafter, it was stirred sufficiently, followed by adding dibenzylideneacetonepalladium (0.4 g, 0.7 mmol) and tricyclohexylphosphine (0.4 g, 1.4 mmol). After 7 hours of reaction, it was cooled to room temperature and the resulting solid was filtered. The solid was dissolved in 431 mL of dichlorobenzene, 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 dichlorobenzene and ethyl acetate to prepare Compound 3-1 in the form of solid (10.5 g, 73%, MS: [M+H]+=631.8).
Compound 3-2-1 (MS: [M+H]+=524) was prepared in the same manner as in step 1 of the preparation method of Compound 3-1, except that A-4 was changed to B-5, and 2-chloro-4-phenyl-6-(phenyl-d5)-1,3,5-triazine was changed to 2-chloro-4-(dibenzo[b, d]furan-3-yl)-6-phenyl-1,3,5-triazine in step 1 of Preparation Example 3-11.
3-2-1 (10 g, 19.1 mmol) and 9H-carbazole-1,3,6,8-d4 (4.7 g, 19.1 mmol) were added to 200 ml of xylene under a nitrogen atmosphere, and the mixture was stirred and refluxed. Then, sodium tert-butoxide (5.5 g, 57.3 mmol) was added thereto. Thereafter, it was stirred sufficiently, followed by adding bis(tri-tert-butylphosphine) palladium (0.3 g, 0.6 mmol). After 4 hours of reaction, it was cooled to room temperature and the resulting solid was filtered. The solid was dissolved in 377 mL of dichlorobenzene, 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 purified by silica column using dichlorobenzene and ethyl acetate to prepare Compound 3-2 in the form of solid (12 g, 95%, MS: [M+H]+=659.2).
Compound 3-3 (MS: [M+H]+=646) was prepared in the same manner as in the preparation method of Compound 3-2, except that Compound B-5 was changed to Compound C-4, 2-chloro-4-(dibenzo[b,d]furan-3-yl)-6-phenyl-1,3,5-triazine was changed to 2-chloro-4,6-diphenyl-1,3,5-triazine, and 9H-carbazole-1,3,6,8-d4 was changed to 3-(phenyl-d5)-9H-carbazole in Preparation Example 3-12.
Compound 3-4 (MS: [M+H]+=633) was prepared in the same manner as in the preparation method of Compound 3-11, except that Compound A-4 was changed to Compound D-4, 2-chloro-4-phenyl-6-(phenyl-d5)-1,3,5-triazine was changed to 2-chloro-4,6-diphenyl-1,3,5-triazine, and triphenylene-2-yl boronic acid was changed to ([1,1′:4′,1″-terphenyl]-4-yl-2″,3″,4″,5″,6″-d5) boronic acid in Preparation Example 3-11.
Compound 3-5-1 (MS: [M+H]+=444) was prepared in the same manner as in step 1 of the preparation method of Compound 3-1, except that 2-chloro-4-phenyl-6-(phenyl-d5)-1,3,5-triazine was changed to 3-bromo-9-phenyl-9H-carbazole in step 1 of Preparation Example 3-11.
Compound 3-5-1 (21.7 g, 49 mmol) and bis(pinacolato) diboron (14.9 g, 58.8 mmol) were added to 434 ml of Diox under a nitrogen atmosphere, and the mixture was stirred and refluxed. Then, potassium acetate (14.1 g, 146.9 mmol) was added thereto. Thereafter, it was stirred sufficiently, followed by adding palladium dibenzylideneacetone palladium (0.8 g, 1.5 mmol) and tricyclohexylphosphine (0.8 g, 2.9 mmol). After 3 hours of reaction, it was cooled to room temperature and the organic layer was filtered to remove salt. Then, the filtered organic layer was distilled. This was dissolved again in 786 mL of chloroform, 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 3-5-2 in the form of solid (20.2 g, 77%, MS: [M+H]+=536.2).
Compound 3-5 (MS: [M+H]+=722) was prepared in the same manner as in step 2 of the preparation method of Compound 3-1, except that Compound 3-1-1 was changed to Compound 3-5-2 and triphenylen-2-yl boronic acid was changed to 2-([1,1′-biphenyl]-3-yl-2′,3′,4′,5′,6′-d5)-4-chloro-6-phenyl-1,3,5-triazine in step 2 of Preparation Example 3-11.
Compound 3-6 (MS: [M+H]+=737) was prepared in the same manner as in the preparation method of Compound 3-2, except that Compound B-5 was changed to Compound F-4, 2-chloro-4-(dibenzo[b,d]furan-3-yl)-6-phenyl-1,3,5-triazine was changed to 2-chloro-4,6-diphenyl-1,3,5-triazine, and 9H-carbazole-1,3,6,8-d4 was changed to 11-phenyl-11,12-dihydroindolo[2,3-a]carbazole-1,3,5,6,7,8,10-d7 in Preparation Example 3-12.
Compound 3-7 (MS: [M+H]+=672) was prepared in the same manner as in the preparation method of Compound 3-5, except that Compound A-4 was changed to Compound E-4, 3-bromo-9-phenyl-9H-carbazole was changed to 4-bromodibenzo[b,d]thiophene, and 2-([1,1′-biphenyl]-3-yl-2′,3′,4′,5′,6′-d5)-4-chloro-6-phenyl-1,3,5-triazine was changed to 2-chloro-4-(dibenzo[b,d]furan-4-yl)-6-phenyl-1,3,5-triazine in Preparation Example 3-15.
Compound 3-8 (MS: [M+H]+=571) was prepared in the same manner as in the preparation method of Compound 3-5, except that Compound A-4 was changed to Compound J-4, 3-bromo-9-phenyl-9H-carbazole was changed to 1-brorobenzene-2,3,4,5,6-d5, and 2-([1,1′-biphenyl]-3-yl-2′,3′,4′,5′,6′-d5)-4-chloro-6-phenyl-1,3,5-triazine was changed to 2-chloro-4-(dibenzo[b,d]furan-3-yl)-6-phenyl-1,3,5-triazine in Preparation Example 3-15.
Compound 3-9-1 was prepared in the same manner as in step 2 of the preparation method of Compound 3-2, except that Compound 3-2-1 was changed to Compound C-3, and 9H-carbazole-1,3,6,8-d4 was changed to 9H-carbazole-1,2,3,4,5,6,7,8-d8 in step 2 of Preparation Example 3-12. Then, Compound 3-8 (MS: [M+H]+=662) was prepared in the same manner as in the preparation method of Compound 3-5, except that Compound 3-5-1 was changed to Compound 3-9-1, and 2-([1,1′-biphenyl]-3-yl-2′,3′,4′,5′,6′-d5)-4-chloro-6-phenyl-1,3,5-triazine was changed to 9-(4-chloro-6-phenyl-1,3,5-triazin-2-yl)-9H-carbazole in step 2-3 of Preparation Example 3-15.
Compound 3-10 (MS: [M+H]+=571) was prepared in the same manner as in the preparation method of Compound 3-2, except that Compound B-5 was changed to Compound E-4, 2-chloro-4-(dibenzo[b,d]furan-3-yl)-6-phenyl-1,3,5-triazine was changed to 2-chloro-4,6-diphenyl-1,3,5-triazine, and 9H-carbazole-1,3,6,8-d4 was changed to 9H-carbazole-1,3,4,5,6,8-d6 in Preparation Example 3-12.
Compound 3-11 (MS: [M+H]+=651) was prepared in the same manner as in the preparation method of Compound 3-2, except that Compound B-5 was changed to Compound H-4, 2-chloro-4-(dibenzo[b,d]furan-3-yl)-6-phenyl-1,3,5-triazine was changed to 2-chloro-4,6-bis(phenyl-d5)-1,3,5-triazine, and 9H-carbazole-1,3,6,8-d4 was changed to 3-phenyl-9H-carbazole in Preparation Example 3-12.
Compound 3-12-1 was prepared in the same manner as in step 2 of the preparation method of Compound 3-2, except that Compound 3-2-1 was changed to Compound G-3, and 9H-carbazole-1,3,6,8-d4 was changed to 9H-carbazole-1,3,4,5,6,8-d6 in step 2 of Preparation Example 3-12. Then, Compound 3-12 (MS: [M+H]+=647) was prepared in the same manner as in the preparation method of Compound 3-5, except that Compound 3-5-1 was changed to Compound 3-12-1, and 2-([1,1′-biphenyl]-3-yl-2′,3′,4′,5′,6′-d5)-4-chloro-6-phenyl-1,3,5-triazine was changed to 2-([1,1′-biphenyl]-3-yl)-4-chloro-6-phenyl-1,3,5-triazine in step 2-3 of Preparation Example 3-15.
Compound 3-13 (MS: [M+H]+=647) was prepared in the same manner as in the preparation method of Compound 3-5, except that Compound A-4 was changed to Compound B-5, 3-bromo-9-phenyl-9H-carbazole was changed to 4-bromo-1,1′-biphenyl, and 2-([1,1′-biphenyl]-3-yl-2′,3′,4′,5′,6′-d5)-4-chloro-6-phenyl-1,3,5-triazine was changed to 2-chloro-4-(dibenzo[b,d]furan-1-yl)-6-(phenyl-d5)-1,3,5-triazine in Preparation Example 3-15.
4-chlorodibenzothiophene (20 g, 0.09 mol) was dissolved in 200 mL of DMF in a 500 mL round-bottom flask under a nitrogen atmosphere, and then NBS (16.5 g, 0.09 mol) was divided into 5 portions and added thereto at 0° C., followed by stirring at room temperature for 6 hours. Thereafter, the solution was depressurized, dissolved in ethyl acetate, and washed with water. Then, the organic layer was separated and all solvents were removed under reduced pressure. This was subjected to column chromatography to obtain Intermediate 3-14-1 (20.6 g, yield 76%, MS:[M+H]+=297).
Compound 3-14-2 was prepared in the same manner as in step 2 of the preparation method of Compound 3-2, except that Compound 3-2-1 was changed to Compound 3-14-1, and 9H-carbazole-1,3,6,8-d4 was changed to 9H-carbazole-1,3,4,5,6,8-d6 in step 2 of Preparation Example 3-12. Then, Compound 3-14 (MS: [M+H]+=592) was prepared in the same manner as in the preparation method of Compound 3-15, except that Compound 3-5-1 was changed to Compound 3-14-2, and 2-([1,1′-biphenyl]-3-yl-2′,3′,4′,5′,6′-d5)-4-chloro-6-phenyl-1,3,5-triazine was changed to 2-chloro-4-phenyl-6-(phenyl-d5)-1,3,5-triazine in step 2-3 of Preparation Example 3-15.
Compound 3-15 (MS: [M+H]+=570) was prepared in the same manner as in the preparation method of Compound 3-2, except that Compound B-5 was changed to Compound G-4, 2-chloro-4-(dibenzo[b,d]furan-3-yl)-6-phenyl-1,3,5-triazine was changed to 2-chloro-4-phenyl-6-(phenyl-d5)-1,3,5-triazine, and 9H-carbazole-1,3,6,8-d4 was changed to 9H-carbazole in Preparation Example 3-12.
Compound 3-16 (MS: [M+H]+=576) was prepared in the same manner as in the preparation method of Compound 3-2, except that Compound B-5 was changed to Compound 1-5, 2-chloro-4-(dibenzo[b,d]furan-3-yl)-6-phenyl-1,3,5-triazine was changed to 2-chloro-4,6-bis(phenyl-d5)-1,3,5-triazine, and 9H-carbazole-1,3,6,8-d4 was changed to dibenzo[b,d]furan-4-yl boronic acid in Preparation Example 3-12.
A glass substrate on which ITO (Indium Tin Oxide) was coated as a thin film to a thickness of 1400 Å 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.
95 wt % of the following compound HT-A and 5 wt % of the following compound PD were thermally vacuum-deposited on the prepared ITO transparent electrode to a thickness of 100 Å to form a hole injection layer. Then, only the following compound HT-A material was deposited to a thickness of 1150 Å to form a hole transport layer. The following compound HT-B was thermally vacuum-deposited thereon to a thickness of 450 Å as an electron blocking layer.
Thereafter, 92 wt % of host materials containing Compound 1-1 as a first host, Compound 2-1 as a second host, and Compound 3-10 as a third host in a weight ratio of 35:35:30 and 8 wt % of the following compound GD were vacuum-deposited to a thickness of 350 Å on the electron blocking layer to form a light emitting layer.
Then, the following compound ET-A was vacuum-deposited to a thickness of 50 Å as a hole blocking layer. Subsequently, the following compounds ET-B and Liq were thermally vacuum-deposited at a ratio 1:1 to a thickness of 300 Å as an electron transport layer, and then Yb was vacuum-deposited to a thickness of 10 Å as an electron injection layer.
Magnesium and silver were deposited on the electron injection layer at a ratio of 1:4 to a thickness of 150 Å 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 to 0.7 Å/sec, the deposition rate of magnesium and silver was maintained at 2 Å/sec, and the degree of vacuum during the deposition was maintained at 2×10−7 to 5×10−6 torr, thereby manufacturing an organic light emitting device.
Organic light emitting devices of Examples 2 to 38 and Comparative Examples 1 to 10 were respectively manufactured in the same manner as in the Example 1, except that the host materials were changed as shown in Table 1 to Table 3 below. Herein, the ratio refers to a weight ratio of the first host, second host and third host. In addition, compounds GH-A, GH-B, and GH-C listed in Table 1 are as follows.
The organic light emitting devices prepared in the above Examples 1 to 38 and Comparative Examples 1 to 10 were heat-treated in an oven at 120° C. for 30 minutes, and then taken out. Then, the voltage, efficiency, and lifespan (T95) were measured by applying a current, and the results are shown in Table 1 to Table 3 below. Herein, the voltage and efficiency were measured by applying a current density of 10 mA/cm2, and T95 means the time taken (hr) until the initial luminance decreases to 95% at a current density of 20 mA/cm2.
In Tables 1 to 3, it was confirmed that the organic light emitting devices of Examples 1 to 38 had significantly lower driving voltage and significantly improved efficiency and lifespan compared to the organic light emitting devices of Comparative Examples 1 to 10.
The indolocarbazole-based compound (first compound) and the biscarbazole-based compound (second compound) have excellent hole transport ability, thereby serving as a P-type host; and the compound in which pyridine, pyrimidine, or triazine is bonded to N of indolocarbazole (third compound) serves as an N-type host.
Since an exciplex is formed when a P-type host and an N-type host are mixed and applied as the host of the light emitting layer, the characteristics of the device can be further improved compared to the case in which only one of the P-type host and the N-type host is applied. This could be confirmed from the fact that the organic light emitting devices of Examples 1 to 38 in which a P-type host and an N-type host are mixed and applied as the host of the light emitting layer had significantly lower driving voltage and significantly improved efficiency and lifespan compared to the organic light emitting devices of Comparative Examples 1 to 4 in which only one of the P-type host and the N-type host is applied.
Further, it was confirmed that the organic light emitting devices of Examples using the two P-type hosts which are the first compound and the second compound, and the N-type host of the third compound (first compound+second compound+third compound) had improved device characteristics compared to the organic light emitting devices of Comparative Example 5 or 6 in which only one P-type host is mixed with the N-type host (first compound+third compound; or second compound+third compound).
The P-type host of the Chemical Formula 1 exhibits low voltage due to its structure containing indolocarbazole, and the P-type host of the Chemical Formula 2 exhibits high efficiency and long lifespan due to its structure containing biscarbazole. Therefore, using a mixture thereof is advantageous for uniformly improving the voltage, efficiency, and lifespan of the device.
In addition, it can be seen that when the mixing ratio of the two P-type hosts of the first compound and the second compound, and the N-type host of the third compound is changed, the voltage, efficiency, and lifespan are changed. Specifically, it was confirmed that the organic light emitting devices of Examples 7 to 9 in which the ratio of the P-type host (structure including biscarbazole) of the second compound is increased compared to the organic light emitting devices of Examples 1 to 3 had simultaneously improved efficiency and lifespan compared to the organic light emitting devices of Examples 1 to 3, since the P-type host of the second compound has high efficiency and long lifespan characteristics.
In addition, it was confirmed that the organic light emitting devices of the Examples had overall improved voltage, efficiency, and lifespan even compared to the organic light emitting device of Comparative Example 8 using a compound having a structure completely different from that of the third compound as an N-type host. This means that the P-type host combination of the first and second compounds exhibits a synergistic effect in all of voltage, efficiency, and lifespan when used in combination with the N-type host of the third compound.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2020-0089021 | Jul 2020 | KR | national |
| 10-2021-0093118 | Jul 2021 | KR | national |
This application is a National Stage Application of International Application No. PCT/KR2021/009191 filed on Jul. 16, 2021, which claims priority to and the benefit of Korean Patent Applications No. 10-2020-0089021 filed on Jul. 17, 2020 and No. 10-2021-0093118 filed on Jul. 15, 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/KR2021/009191 | 7/16/2021 | WO |
