Organic light-emitting device

JP7631633B2Active Publication Date: 2025-02-19LG CHEM LTD
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Patent Information

Application Number
JP2023537458
Authority / Receiving Office
JP · JP
Patent Type
Patents
Current Assignee / Owner
Priority Date
2022-05-04
Filing Date
2022-05-06
Publication Date
2025-02-19
Estimated Expiration
2042-05-06

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Benefits of technology

【0009】 上述した有機発光素子は、発光層に前記化学式1で表される化合物および前記化学式2で表される化合物の有機アロイを含むことによって、有機発光素子において効率の向上、低い駆動電圧および/または寿命特性を向上させることができる。

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Abstract

The present invention provides an organic light emitting device with improved driving voltage, efficiency and lifetime.
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Description

[Technical field]

[0001] [CROSS REFERENCE TO RELATED APPLICATIONS] This application claims the benefit of priority based on Korean Patent Application No. 10-2021-0058831 dated May 6, 2021 and Korean Patent Application No. 10-2022-0055698 dated May 4, 2022, and all contents disclosed in the documents of said Korean patent applications are incorporated herein by reference.

[0002] The present invention relates to an organic light emitting device with improved driving voltage, efficiency and lifetime. [Background technology]

[0003] Generally, organic light emitting phenomenon refers to a phenomenon in which electrical energy is converted into light energy using an organic material. Organic light emitting devices using the organic light emitting phenomenon have a wide viewing angle, excellent contrast, and fast response time, and are excellent in brightness, driving voltage, and response speed characteristics, and therefore many researches are being conducted on these devices.

[0004] An organic light-emitting device generally has a structure including a positive electrode, a negative electrode, and an organic layer between the positive electrode and the negative electrode. The organic layer is often a multi-layer structure composed of different materials to improve the efficiency and safety of the organic light-emitting device, for example, a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, an electron injection layer, etc. In such an organic light-emitting device structure, when a voltage is applied between two electrodes, holes are injected from the positive electrode and electrons are injected from the negative electrode into the organic layer. When the injected holes and electrons come into contact with each other, excitons are formed, and when the excitons fall back to the ground state, light is emitted.

[0005] In the above organic light emitting devices, there is a continuing demand for development of organic light emitting devices having improved driving voltage, efficiency and life span. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Korean Patent Publication No. 10-2000-0051826 Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention relates to an organic light emitting device with improved driving voltage, efficiency and lifetime. [Means for solving the problem]

[0008] The present invention provides an organic light-emitting device comprising: a positive electrode; a negative electrode; and a light-emitting layer between the positive electrode and the negative electrode, The light-emitting layer is an organic compound represented by the following Chemical Formula 1 and the following Chemical Formula 2: Alloy An organic light emitting device, comprising: [Chemical formula 1] [ka] In the above Chemical Formula 1, A is a benzene ring fused to two adjacent rings; X1, X2 and X3 are each independently CH or N, and at least one of X1, X2 and X3 is N; Ar1 and Ar2 are each independently a substituted or unsubstituted aryl having 6 to 60 carbon atoms; or a substituted or unsubstituted heteroaryl having 2 to 60 carbon atoms containing at least one selected from the group consisting of N, O, and S; Ar3 is a substituted or unsubstituted aryl having 6 to 60 carbon atoms; or a substituted or unsubstituted heteroaryl having 2 to 60 carbon atoms containing at least one selected from the group consisting of N, O, and S; R1 is independently hydrogen; deuterium; a substituted or unsubstituted aryl having 6 to 60 carbon atoms; or a substituted or unsubstituted heteroaryl having 2 to 60 carbon atoms containing at least one selected from the group consisting of N, O, and S; n1 is an integer from 1 to 10, [Chemical formula 2] [ka] In the above Chemical Formula 2, Ar4 and Ar5 are each independently a substituted or unsubstituted aryl having 6 to 60 carbon atoms; or a substituted or unsubstituted heteroaryl having 2 to 60 carbon atoms containing at least one selected from the group consisting of N, O, and S; R2 is independently hydrogen; deuterium; a substituted or unsubstituted aryl having 6 to 60 carbon atoms; or a substituted or unsubstituted heteroaryl having 2 to 60 carbon atoms containing at least one selected from the group consisting of N, O, and S; At least one of Ar4 and Ar5 is substituted with one or more deuterium atoms or at least one of R2 is deuterium; n2 is an integer from 1 to 10. Effect of the Invention

[0009] The organic light-emitting device described above includes an organic compound represented by the chemical formula 1 and an organic compound represented by the chemical formula 2 in an emitting layer. Alloy By including the compound, it is possible to improve the efficiency, reduce the driving voltage, and / or improve the life characteristics of the organic light emitting device. [Brief description of the drawings]

[0010] [Figure 1] 1 is a diagram showing an example of an organic light-emitting device composed of a substrate 1, a positive electrode 2, a light-emitting layer 3, and a negative electrode 4. FIG. [Diagram 2] FIG. 1 shows an example of an organic light-emitting device consisting of a substrate 1, a positive electrode 2, a hole injection layer 5, a hole transport layer 6, an electron blocking layer 7, a light-emitting layer 3, a hole blocking layer 8, an electron transport layer 9, an electron injection layer 10, and a negative electrode 4. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] The present invention will now be described in more detail to aid in its understanding.

[0012] In this specification, [ka] or [ka] denotes a bond that is connected to another substituent.

[0013] In the present specification, the term "substituted or unsubstituted" means that the group is substituted or unsubstituted with one or more substituents selected from the group consisting of deuterium, halogen, nitrile, nitro, hydroxy, carbonyl, ester, imide, amino, phosphine oxide, alkoxy, aryloxy, alkylthio, arylthio, alkylsulfoxy, arylsulfoxy, silyl, boron, alkyl, cycloalkyl, alkenyl, aryl, aralkyl, aralkenyl, alkylaryl, alkylamine, aralkylamine, heteroarylamine, arylamine, arylphosphine, or heterocyclic group containing one or more of N, O, and S atoms, or that the group is substituted or unsubstituted with two or more of the above-listed substituents. For example, the "substituent having two or more substituents connected" may be a biphenyl group. That is, the biphenyl group may be an aryl group, and may be interpreted as a substituent having two phenyl groups connected.

[0014] In this specification, the number of carbon atoms in the carbonyl group is not particularly limited, but it is preferable that the number of carbon atoms is 1 to 40.

[0015] Specifically, the substituent may have the following structure, but is not limited thereto. [ka]

[0016] In this specification, the oxygen of the ester group may be substituted with a linear, branched or cyclic alkyl group having 1 to 25 carbon atoms, or an aryl group having 6 to 25 carbon atoms. Specifically, the substituent may be one of the following structural formulas, but is not limited thereto. [ka]

[0017] In this specification, the number of carbon atoms of the imido group is not particularly limited, but is preferably 1 to 25. Specifically, the imido group may have a substituent having the following structure, but is not limited thereto. [ka]

[0018] In this specification, specific examples of the silyl group include a trimethylsilyl group, a triethylsilyl group, a t-butyldimethylsilyl group, a vinyldimethylsilyl group, a propyldimethylsilyl group, a triphenylsilyl group, a diphenylsilyl group, and a phenylsilyl group, but are not limited to these.

[0019] In this specification, specific examples of the boron group include a trimethyl boron group, a triethyl boron group, a t-butyl dimethyl boron group, a triphenyl boron group, and a phenyl boron group, but are not limited to these.

[0020] As used herein, examples of halogen groups include fluorine, chlorine, bromine, or iodine.

[0021] In this specification, the alkyl group may be linear or branched, and the number of carbon atoms is not particularly limited, but is preferably 1 to 40. According to one embodiment, the number of carbon atoms of the alkyl group is 1 to 20. According to yet another embodiment, the number of carbon atoms of the alkyl group is 1 to 10. According to yet another embodiment, the number of carbon atoms of the alkyl group is 1 to 6. Specific examples of alkyl groups include, but are not limited to, 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-methylbutyl, 2-ethylhexyl, 2-propylpentyl, n-nonyl, 2,2-dimethylheptyl, 1-ethyl-propyl, 1,1-dimethyl-propyl, isohexyl, 4-methylhexyl, 5-methylhexyl, and the like.

[0022] In this specification, the alkenyl group may be linear or branched, and the number of carbon atoms is not particularly limited, but is preferably 2 to 40. According to one embodiment, the number of carbon atoms of the alkenyl group is 2 to 20. According to yet another embodiment, the number of carbon atoms of the alkenyl group is 2 to 10. According to yet another embodiment, the number of carbon atoms of the alkenyl group is 2 to 6. Specific examples include, but are not limited to, 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, and a styrenyl group.

[0023] In the present specification, the cycloalkyl group is not particularly limited, but preferably has 3 to 60 carbon atoms, and in one embodiment, the cycloalkyl group has 3 to 30 carbon atoms. In another embodiment, the cycloalkyl group has 3 to 20 carbon atoms. In another embodiment, the cycloalkyl group has 3 to 6 carbon atoms. Specific examples include, but are not limited to, cyclopropyl, cyclobutyl, cyclopentyl, 3-methylcyclopentyl, 2,3-dimethylcyclopentyl, cyclohexyl, 3-methylcyclohexyl, 4-methylcyclohexyl, 2,3-dimethylcyclohexyl, 3,4,5-trimethylcyclohexyl, 4-tert-butylcyclohexyl, cycloheptyl, and cyclooctyl.

[0024] In the present specification, the aryl group is not particularly limited, but preferably has 6 to 60 carbon atoms, and may be a monocyclic aryl group or a polycyclic aryl group. According to one embodiment, the aryl group has 6 to 30 carbon atoms. According to one embodiment, the aryl group has 6 to 20 carbon atoms. The monocyclic aryl group may be, but is not limited to, a phenyl group, a biphenyl group, a terphenyl group, etc. The polycyclic aryl group may be, but is not limited to, a naphthyl group, an anthracenyl group, a phenanthryl group, a pyrenyl group, a perylenyl group, a chrysenyl group, a fluorenyl group, etc.

[0025] In the present specification, the fluorenyl group may be substituted, and two substituents may be bonded to each other to form a spiro structure. When the fluorenyl group is substituted, [ka] However, the present invention is not limited to these.

[0026] In this specification, the heterocyclic group is a heterocyclic group containing one or more of O, N, Si and S as a hetero element, and the number of carbon atoms is not particularly limited, but preferably has 2 to 60 carbon atoms. Examples of heterocyclic groups include, but are not limited to, thiophene, furan, pyrrole, imidazole, thiazole, oxazole, oxadiazole, triazole, pyridyl, bipyridyl, pyrimidyl, triazine, acridyl, pyridacin, pyrazinyl, quinolinyl, quinazoline, quinoxalinyl, phthalazinyl, pyridopyrimidinyl, pyridopyrazinyl, pyrazinopyrazinyl, isoquinoline, indole, carbazole, benzoxazole, benzimidazole, benzothiazole, benzocarbazole, benzothiophene, dibenzothiophene, benzofuranyl, phenanthroline, isoxazolyl, thiadiazolyl, phenothiazinyl, and dibenzofuranyl.

[0027] In this specification, the above-mentioned explanation regarding the aryl group is applicable to the aryl group among the aralkyl group, the aralkenyl group, the alkylaryl group, and the arylamine group. In this specification, the above-mentioned explanation regarding the alkyl group is applicable to the alkyl group among the aralkyl group, the alkylaryl group, and the alkylamine group. In this specification, the above-mentioned explanation regarding the heterocyclic group is applicable to the heteroaryl among the heteroarylamine. In this specification, the above-mentioned explanation regarding the alkenyl group is applicable to the alkenyl group among the aralkenyl group. In this specification, the above-mentioned explanation regarding the aryl group is applicable to the arylene, except that it is a divalent group. In this specification, the above-mentioned explanation regarding the heterocyclic group is applicable to the heteroarylene, except that it is a divalent group. In this specification, the above-mentioned explanation regarding the aryl group or the cycloalkyl group is applicable to the hydrocarbon ring, except that it is not a monovalent group but is formed by bonding two substituents. In this specification, the above-mentioned explanation regarding the heterocyclic group is applicable to the heterocycle, except that it is not a monovalent group but is formed by bonding two substituents.

[0028] On the other hand, in the present invention, Alloy The term "organic alloy" refers to a result of a pre-treatment of two or more single organic compounds, which may result in a chemical interaction between the single organic compounds. The pre-treatment may be, for example, a heat treatment process such as heating and sublimation followed by cooling, but is not limited thereto.

[0029] The present invention will be described in detail below for each component.

[0030] Positive and negative electrodes The positive electrode and the negative electrode used in the present invention refer to electrodes used in an organic light-emitting device.

[0031] The positive electrode material is preferably a material having a large work function so that holes can be easily injected into the organic layer. Specific examples of the positive electrode material include, but are not limited to, metals such as vanadium, chromium, copper, zinc, and gold, or alloys thereof; metal oxides such as zinc oxide, indium oxide, indium tin oxide (ITO), and indium zinc oxide (IZO); combinations of metals and oxides such as ZnO:Al or SnO2:Sb; and conductive polymers such as poly(3-methylthiophene), poly[3,4-(ethylene-1,2-dioxy)thiophene] (PEDOT), polypyrrole, and polyaniline.

[0032] The negative electrode material is preferably a material having a small work function so that electrons can be easily injected into the organic layer. Specific examples of the negative electrode material include, but are not limited to, metals such as magnesium, calcium, sodium, potassium, titanium, indium, yttrium, lithium, gadolinium, aluminum, silver, tin, and lead, or alloys thereof; and multilayer structures such as LiF / Al or LiO2 / Al.

[0033] Hole injection layer The organic light-emitting device according to the present invention may further include a hole injection layer on the positive electrode, if necessary.

[0034] The hole injection layer is a layer that injects holes from the electrode, and the hole injection material is preferably a compound that has the ability to transport holes, has a hole injection effect from the positive electrode, has an excellent hole injection effect on the light emitting layer or light emitting material, prevents the movement of excitons generated in the light emitting layer to the electron injection layer or electron injection material, and has excellent thin film forming ability. In addition, it is preferable that the HOMO (highest occupied molecular orbital) of the hole injection material is between the work function of the positive electrode material and the HOMO of the surrounding organic layer.

[0035] Specific examples of hole injection materials include, but are not limited to, metal porphyrin, oligothiophene, arylamine-based organic materials, hexanitrile hexaazatriphenylene-based organic materials, quinacridone-based organic materials, perylene-based organic materials, anthraquinone, and polyaniline and polythiophene-based conductive polymers.

[0036] Hole transport layer The organic light-emitting device according to the present invention may optionally include a hole transport layer on the anode (or on the hole injection layer, if present).

[0037] The hole transport layer is a layer that receives holes from the positive electrode or the hole injection layer and transports the holes to the light emitting layer. As the hole transport material, a material that can receive holes from the positive electrode or the hole injection layer and move them to the light emitting layer and has high mobility for holes is preferable.

[0038] Specific examples of the hole transport material include, but are not limited to, arylamine-based organic materials, conductive polymers, and block copolymers having both conjugated and non-conjugated portions.

[0039] electron blocking layer The organic light-emitting device according to the present invention may optionally include an electron blocking layer on the hole transport layer.

[0040] The electron blocking layer is a layer placed between the hole transport layer and the light emitting layer to prevent the electrons injected from the negative electrode from passing to the hole transport layer without being recombined in the light emitting layer, and is also called an electron inhibiting layer. The electron blocking layer is preferably made of a material having a smaller electron affinity than the electron transport layer.

[0041] Emitting layer The light-emitting layer used in the present invention means a layer capable of emitting light in the visible light region by combining holes and electrons transferred from the positive and negative electrodes. In general, the light-emitting layer includes a host material and a dopant material, and the present invention includes an organic layer obtained by pretreating the compound represented by the above Chemical Formula 1 and the compound represented by the above Chemical Formula 2. Alloy is available to the host.

[0042] Preferably, the compound represented by Chemical Formula 1 is represented by any one of the following Chemical Formulas 1-1 to 1-4: [ka] In the above Chemical Formula 1-1 to Chemical Formula 1-4, X1, X2, X3, Ar1 to Ar3, R1 and n1 are as defined in Chemical Formula 1 above.

[0043] Preferably, Ar1 and Ar2 may each independently be a substituted or unsubstituted aryl having 6 to 20 carbon atoms; or a substituted or unsubstituted heteroaryl having 2 to 20 carbon atoms containing at least one selected from the group consisting of N, O, and S. More preferably, Ar1 and Ar2 may each independently be phenyl, biphenylyl, terphenylyl, dibenzofuranyl, dibenzothiophenyl, dimethylfluorenyl, or phenyl substituted with five deuterium atoms. Most preferably, Ar1 and Ar2 may each independently be any one selected from the group consisting of: [ka]

[0044] Preferably, Ar3 may be a substituted or unsubstituted aryl having 6 to 20 carbon atoms; or a substituted or unsubstituted heteroaryl having 2 to 20 carbon atoms containing at least one selected from the group consisting of N, O and S. More preferably, Ar3 may be a substituted or unsubstituted aryl having 6 to 20 carbon atoms. More preferably, Ar3 may be phenyl, biphenylyl, terphenylyl, phenyl substituted with 5 deuterium atoms, or terphenylyl substituted with 5 to 13 deuterium atoms. Most preferably, Ar3 may be any one selected from the group consisting of: [ka] Preferably, R1 may be hydrogen or deuterium.

[0045] Representative examples of the compound represented by Formula 1 are as follows: [ka] [ka] [ka] [ka] [ka] [ka] [ka] The compound represented by Chemical Formula 1 can be prepared, for example, by the method shown in Reaction Scheme 1 below, and the remaining compounds can be prepared by similar methods.

[0046] [Reaction Scheme 1] [ka]

[0047] In the reaction formula 1, A, X1, X2, X3, Ar1, Ar2, Ar3, R1 and n1 are as defined in the chemical formula 1, and Z1 is a halogen, preferably Z1 is chloro or bromo.

[0048] The reaction scheme 1 is an amine substitution reaction, which is preferably carried out in the presence of a palladium catalyst and a base, and the reactive group for the amine substitution reaction can be changed according to those known in the art. The preparation method is more specifically described in the preparation examples described below.

[0049] Preferably, Ar4 and Ar5 may each independently be a substituted or unsubstituted aryl having 6 to 20 carbon atoms; or a substituted or unsubstituted heteroaryl having 2 to 20 carbon atoms containing at least one selected from the group consisting of N, O, and S. More preferably, Ar4 and Ar5 may each independently be phenyl, biphenylyl, biphenylyl substituted with one methyl, terphenylyl, dimethylfluorenyl, dimethylfluorenylphenyl, dibenzofuranyl, dibenzothiophenyl, dibenzofuranylphenyl, or dibenzothiophenylphenyl, and the phenyl, biphenylyl, biphenylyl substituted with one methyl, terphenylyl, dimethylfluorenyl, dimethylfluorenylphenyl, dibenzofuranyl, dibenzothiophenyl, dibenzofuranylphenyl, or dibenzothiophenylphenyl may be unsubstituted or substituted with deuterium.

[0050] Preferably, each R2 may be independently hydrogen, deuterium, a substituted or unsubstituted aryl having 6 to 20 carbon atoms, or a substituted or unsubstituted heteroaryl having 2 to 20 carbon atoms containing at least one selected from the group consisting of N, O, and S. More preferably, each R2 may be independently hydrogen or deuterium (D).

[0051] Representative examples of the compound represented by Formula 2 are as follows: [ka] In the above group, a+b+c+d+e are integers from 1 to 28, [ka] In the above group, a+b+c+d+e+f are integers from 1 to 32, [ka] In the above group, a+b+c+d is an integer between 1 and 26, [ka] [ka] [ka] [ka] [ka] In the above group, a+b+c+d+e are integers from 1 to 30, [ka] In the above group, a+b+c+d are integers from 1 to 32, [ka] [ka] In the above group, a+b+c+d+e are integers from 1 to 36, [ka] In the above group, a+b+c+d+e are integers from 1 to 30, [ka] In the above group, a+b+c+d+e are integers from 1 to 32, [ka] In the above group, a+b+c+d+e is an integer between 1 and 36.

[0052] The compound represented by Chemical Formula 2 can be prepared, for example, by a method as shown in Reaction Scheme 2 below, and the remaining compounds can be prepared by a similar method.

[0053] [Reaction Scheme 2] [ka]

[0054] In the above reaction formula 2, Ar4, Ar5, R2 and n2 are as defined in the above chemical formula 2, Z2 and Z3 are each independently a halogen, preferably Z2 and Z3 are each independently chloro or bromo.

[0055] The reaction scheme 2 is an amine substitution reaction, which is preferably carried out in the presence of a palladium catalyst and a base, and the reactive group for the amine substitution reaction can be changed according to those known in the art. The preparation method is more specifically described in the preparation examples described below.

[0056] Preferably, the organic Alloy In the composition, the weight ratio of the compound represented by Chemical Formula 1 to the compound represented by Chemical Formula 2 is 10:90 to 90:10, and more preferably 20:80 to 80:20, 30:70 to 70:30, or 40:60 to 60:40.

[0057] Meanwhile, the light-emitting layer may further include a dopant in addition to the host. The dopant material is not particularly limited as long as it is a material used in an organic light-emitting device. For example, aromatic amine derivatives, styrylamine compounds, boron complexes, fluoranthene compounds, metal complexes, etc. are included. Specifically, aromatic amine derivatives are condensed aromatic ring derivatives having a substituted or unsubstituted arylamino group, such as pyrene, anthracene, chrysene, and periplanthene, which have an arylamino group, and styrylamine compounds are compounds in which at least one arylvinyl group is substituted on a substituted or unsubstituted arylamine, and one or more substituents 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. Specifically, styrylamine, styryldiamine, styryltriamine, styryltetraamine, etc. are included, but are not limited thereto. In addition, metal complexes include, but are not limited to, iridium complexes and platinum complexes.

[0058] Hole Blocking Layer The organic light-emitting device according to the present invention may optionally include a hole-blocking layer on the light-emitting layer.

[0059] The hole blocking layer is a layer disposed between the electron transport layer and the light emitting layer to prevent holes injected from the positive electrode from being recombined in the light emitting layer and passing to the electron transport layer, and is also called a hole blocking layer. A material having a large ionization energy is preferable for the hole blocking layer.

[0060] electron transport layer The organic light-emitting device according to the present invention may optionally include an electron transport layer on the light-emitting layer.

[0061] The electron transport layer is a layer that receives electrons from the negative electrode or the electron injection layer formed on the negative electrode, transports the electrons to the light-emitting layer, and suppresses the transmission of holes from the light-emitting layer. As the electron transport material, a material that can efficiently receive electrons injected from the negative electrode and transfer them to the light-emitting layer and has high mobility for electrons is preferable.

[0062] Specific examples of the electron transport material include, but are not limited to, Al complex of 8-hydroxyquinoline; complexes containing Alq3; organic radical compounds; hydroxyflavone-metal complexes. The electron transport layer can be used with any desired cathode material as used according to the prior art. In particular, examples of suitable cathode materials are those that have a low work function and are usually followed by an aluminum or silver layer. In particular, cesium, barium, calcium, ytterbium and samarium, each followed by an aluminum or silver layer.

[0063] electron injection layer The organic light-emitting device according to the present invention may further comprise an electron injection layer on the light-emitting layer (or on the electron transport layer, if present) as required.

[0064] The electron injection layer is a layer that injects electrons from an electrode, and it is preferable to use a compound that has the ability to transport electrons, has an excellent electron injection effect from the negative electrode, an excellent electron injection effect for the light-emitting layer or the light-emitting material, prevents the movement of excitons generated in the light-emitting layer to the hole injection layer, and has excellent thin-film forming ability.

[0065] Specific examples of the substance used in the electron injection layer include, but are not limited to, fluorenone, anthraquinone dimethane, diphenoquinone, thiopyran dioxide, oxazole, oxadiazole, triazole, imidazole, perylene tetracarboxylic acid, preolenylidene methane, anthrone, and derivatives thereof, metal complex compounds, and nitrogen-containing five-membered ring derivatives.

[0066] Examples of the metal complex compound include, but are not limited to, 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, and bis(2-methyl-8-quinolinato)(2-naphtholato)gallium.

[0067] Organic light-emitting device The structure of an organic light-emitting device according to the present invention is shown in Figures 1 and 2. Figure 1 is a diagram showing an example of an organic light-emitting device consisting of a substrate 1, a positive electrode 2, a light-emitting layer 3, and a negative electrode 4. Figure 2 is a diagram showing an example of an organic light-emitting device consisting of a substrate 1, a positive electrode 2, a hole injection layer 5, a hole transport layer 6, an electron blocking layer 7, a light-emitting layer 3, a hole blocking layer 8, an electron transport layer 9, an electron injection layer 10, and a negative electrode 4.

[0068] The organic light emitting device according to the present invention may be manufactured by sequentially stacking the above-mentioned components. In this case, a metal or conductive metal oxide or alloy thereof may be deposited on a substrate using a physical vapor deposition (PVD) method such as sputtering or e-beam evaporation to form a positive electrode, and the above-mentioned layers may be formed thereon, and then a material to be used as a negative electrode may be deposited thereon. In addition to this method, an organic light emitting device may be manufactured by sequentially depositing a negative electrode material on a substrate in the reverse order of the above-mentioned components to a positive electrode material (WO2003 / 012890). In addition, the light emitting layer may be formed by a solution coating method as well as a vacuum deposition method of a host and a dopant. Here, the solution coating method means, but is not limited to, spin coating, dip coating, doctor blading, ink jet printing, screen printing, spraying, roll coating, etc.

[0069] Meanwhile, the organic light emitting device according to the present invention may be a bottom emission device, a top emission device, or a double-sided emission device, and may be a bottom emission device which requires relatively high light emitting efficiency.

[0070] The present invention will be described in more detail below to help understanding of the present invention, however, the following examples are merely illustrative of the present invention and are not intended to limit the scope of the present invention.

[0071] [Production Example 1: Synthesis of Compound] Preparation Example 1-1: Synthesis of Compound 1-1

[0072] Step 1) Synthesis of compound 1-1-a [ka] In a nitrogen atmosphere, 11,12-dihydroindolo[2,3-a]carbazole (15.0 g, 58.5 mmol) and 3-bromo-1,1':3',1''-terphenyl (19.9 g, 64.4 mmol) were added to toluene 300 ml and 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. After 9 hours of reaction, the mixture was cooled to room temperature, and the organic layer was separated using chloroform and water, and the organic layer was distilled. This was further dissolved in chloroform, washed twice with water, and the organic layer was separated. After stirring with anhydrous magnesium sulfate, the mixture was filtered and the filtrate was distilled under reduced pressure. The concentrated compound was purified by silica gel column chromatography to produce 17.6 g of compound 1-1-a (yield 62%, MS: [M+H] + =486).

[0073] Step 2) Synthesis of compound 1-1 [ka] Compound 1-1-a (15.0 g, 31.0 mmol) and 2-chloro-4,6-diphenyl-1,3,5-triazine (9.1 g, 34 mmol) were added to toluene 300 ml and stirred and refluxed in a nitrogen atmosphere. 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. After reacting for 11 hours, the mixture was cooled to room temperature, and the organic layer was separated using chloroform and water, and the organic layer was distilled. This was further dissolved in chloroform, washed twice with water, and the organic layer was separated. After stirring, anhydrous magnesium sulfate was added and filtered, and the filtrate was distilled under reduced pressure. The concentrated compound was purified by silica gel column chromatography, and then sublimation purification was performed to produce 8.2 g of compound 1-1 (yield 37%, MS: [M+H] + =717).

[0074] Preparation Example 1-2: Synthesis of Compound 1-2 [ka] Compound 1-2 was prepared in the same manner as compound 1-1, except that in preparation example 1-1, 3-bromo-1,1':3',1''-terphenyl was replaced with 4-bromo-1,1'-biphenyl and 2-chloro-4,6-diphenyl-1,3,5-triazine was replaced with 2-([1,1'-biphenyl]-4-yl)-4-chloro-6-phenyl-1,3,5-triazine was used (MS[M+H] + =717).

[0075] Preparation Example 1-3: Synthesis of Compound 1-3 [ka] Compound 1-3 was prepared in the same manner as compound 1-1, except that in preparation example 1-1, 3-bromo-1,1':3',1''-terphenyl was replaced with 3-bromo-1,1'-biphenyl and 2-chloro-4,6-diphenyl-1,3,5-triazine was replaced with 2-([1,1'-biphenyl]-4-yl)-4-chloro-6-phenyl-1,3,5-triazine. (MS [M+H] + =717).

[0076] Preparation Example 1-4: Synthesis of Compound 1-4 [ka] Compound 1-4 was prepared in the same manner as compound 1-1, except that 11,12-dihydroindolo[2,3-a]carbazole-1,3,4,5,6,8,10-d7 was used instead of 11,12-dihydroindolo[2,3-a]carbazole in Preparation Example 1-1. (MS [M+H] + =724)

[0077] Preparation Example 1-5: Synthesis of Compound 1-5 [ka] Compound 1-5 was prepared in the same manner as in Preparation Example 1-1, except that 11,12-dihydroindolo[2,3-a]carbazole was replaced with 5,8-dihydroindolo[2,3-c]carbazole, 3-bromo-1,1':3',1''-terphenyl was replaced with bromobenzene, and 2-chloro-4,6-diphenyl-1,3,5-triazine was replaced with 2-([1,1'-biphenyl]-4-yl)-4-chloro-6-phenyl-1,3,5-triazine in Preparation Example 1-1. (MS [M+H] + =641).

[0078] Preparation Example 1-6: Synthesis of Compound 1-6 [ka] Compound 1-6 was prepared in the same manner as in Preparation Example 1-1, except that 11,12-dihydroindolo[2,3-a]carbazole was replaced with 5,7-dihydroindolo[2,3-b]carbazole, 3-bromo-1,1':3',1''-terphenyl was replaced with 1-bromobenzene-2,3,4,5,6-d5, and 2-chloro-4,6-diphenyl-1,3,5-triazine was replaced with 2-([1,1'-biphenyl]-3-yl)-4-chloro-6-phenyl-1,3,5-triazine in Preparation Example 1-1. (MS[M+H] + =646).

[0079] Preparation Example 1-7: Synthesis of Compound 1-7 [ka] Compound 1-7 was prepared in the same manner as in Preparation Example 1-1, except that 11,12-dihydroindolo[2,3-a]carbazole was replaced with 5,11-dihydroindolo[3,2-b]carbazole, 3-bromo-1,1':3',1''-terphenyl was replaced with bromobenzene, and 2-chloro-4,6-diphenyl-1,3,5-triazine was replaced with 2-([1,1'-biphenyl]-3-yl)-4-chloro-6-(dibenzo[b,d]thiophen-4-yl)-1,3,5-triazine in Preparation Example 1-1. (MS[M+H] + =747).

[0080] Preparation Example 1-8: Synthesis of Compound 2-1 [ka] In a nitrogen atmosphere, 5,8-dihydroindolo[2,3-c]carbazole-1,2,4,6,7,9,11,12-d8 (15.0g, 56.7mmol) and 4-bromo-1,1'-biphenyl (14.5g, 62.4mmol) were added to 300ml of toluene and stirred and refluxed. Then, sodium tert-butoxide (8.2g, 85.1mmol) and bis(tri-tert-butylphosphine)palladium(0) (0.9g, 1.7mmol) were added. After reacting for 10 hours, the mixture was cooled to room temperature, and the organic layer was separated using chloroform and water, and the organic layer was distilled. This was further dissolved in chloroform and washed twice with water, and the organic layer was separated. Anhydrous magnesium sulfate was added and stirred, and the filtrate was filtered and distilled under reduced pressure. The concentrated compound was purified by silica gel column chromatography, and then purified by sublimation to produce 11.9 g of compound 2-1 (yield 37%, MS: [M+H] + =570).

[0081] Preparation Example 1-9: Synthesis of Compound 2-2 Step 1) Synthesis of compound 2-2-a [ka] In a nitrogen atmosphere, 5,8-dihydroindolo[2,3-c]carbazole (15.0g, 58.5mmol) and 4-bromo-1,1'-biphenyl-2,2',3,3',4',5,5',6,6'-d9 (15.6g, 64.4mmol) were added to 300ml of toluene and stirred and refluxed. Then, sodium tert-butoxide (8.4g, 87.8mmol) and bis(tri-tert-butylphosphine)palladium(0) (0.9g, 1.8mmol) were added. After reacting for 11 hours, the mixture was cooled to room temperature, and the organic layer was separated using chloroform and water, and the organic layer was distilled. This was further dissolved in chloroform and washed twice with water, and the organic layer was separated, and anhydrous magnesium sulfate was added and stirred, and the filtrate was distilled under reduced pressure. The concentrated compound was purified by silica gel column chromatography to produce 17.6 g of compound 2-2-a (yield 72%, MS: [M+H] + =419).

[0082] Step 2) Synthesis of compound 2-2 [ka] Compound 2-2-a (15.0 g, 35.9 mmol) and 4-bromo-1,1':3',1''-terphenyl (12.2 g, 39.5 mmol) were added to toluene 300 ml and stirred and refluxed in a nitrogen atmosphere. Then, sodium tert-butoxide (5.2 g, 53.9 mmol) and bis(tri-tert-butylphosphine)palladium(0) (0.6 g, 1.1 mmol) were added. After reacting for 7 hours, the mixture was cooled to room temperature, and the organic layer was separated using chloroform and water, and the organic layer was distilled. This was further dissolved in chloroform and washed twice with water, and the organic layer was separated. Anhydrous magnesium sulfate was added and stirred, and then filtered, and the filtrate was distilled under reduced pressure. The concentrated compound was purified by silica gel column chromatography, and then sublimation purification was performed to produce 9.3 g of compound 2-2 (yield 40%, MS: [M+H] +=647).

[0083] Preparation Example 1-10: Synthesis of Compound 2-3 [ka] Compound 2-3 was prepared in the same manner as in Compound 2-2, except that in Preparation Example 1-9, 5,8-dihydroindolo[2,3-c]carbazole was replaced with 5,8-dihydroindolo[2,3-c]carbazole-1,2,4,6,7,9,11,12-d8, 4-bromo-1,1'-biphenyl-2,2',3,3',4',5,5',6,6'-d9 was replaced with 3-bromo-1,1'-biphenyl, and 4-bromo-1,1':3',1''-terphenyl was replaced with 3-bromodibenzo[b,d]furan-1,2,4,6,8,9-d6 (MS[M+H] + =590).

[0084] [Production example 2: organic Alloy Manufacturing Production example 2-1: Organic Alloy Manufacturing 1 Compound 1-1 and compound 2-1 were mixed in a weight ratio of 40:60 and placed in a vacuum chamber, and the temperature was raised under a pressure of 10-2 Torr or less to melt the two mixtures. After 1 hour, the mixture was cooled to room temperature to obtain a solid product. The product was crushed in a mixer to obtain an organic compound in powder form. Alloy I got 1.

[0085] Production Examples 2-2 to 2-7, and Production Examples 2-A to 2-D Except for the changes in the mixed materials as shown in Table 1 below, Alloy Using the same manufacturing method as 1, Alloy 2~Organic Alloy 7, and organic Alloy A~Organic Alloy Compounds PH-1 to PH-4 in Table 1 below are as follows.

[0086] [ka]

[0087] [Table 1]

[0088] [Example] Example 1: Fabrication of an organic light-emitting device A glass substrate coated with a 1400 Å-thick thin film of ITO (Indium Tin Oxide) was placed in distilled water with detergent dissolved therein and ultrasonically cleaned. The detergent used was a product of Fischer Co., and the distilled water used was distilled water that had been filtered a second time with a filter made by Millipore Co. The ITO was washed for 30 minutes, then ultrasonically cleaned twice with distilled water for 10 minutes. After the distilled water cleaning was completed, the substrate was ultrasonically cleaned with solvents of isopropyl alcohol, acetone, and methanol, dried, and then transferred to a plasma cleaning device. The substrate was then cleaned for 5 minutes using oxygen plasma, and then transferred to a vacuum deposition device.

[0089] On the ITO transparent electrode thus prepared, 95 wt% of compound HT-A and 5 wt% of compound PD were thermally vacuum deposited to a thickness of 100 Å to form a hole injection layer, and then compound HT-A alone was deposited to a thickness of 1150 Å to form a hole transport layer, on which compound HT-B was thermally vacuum deposited to a thickness of 450 Å as an electron blocking layer.

[0090] Next, the organic layer prepared in Preparation Example 2-1 was coated on the electron blocking layer with a thickness of 350 Å. Alloy The light-emitting layer was formed by vacuum deposition of 1 and the dopant compound GD in a weight ratio of 92:8.

[0091] Next, the following compound ET-A was vacuum-deposited to a thickness of 50 Å for the hole blocking layer, the following compound ET-B and compound Liq were thermally vacuum-deposited in a weight ratio of 1:1 to a thickness of 300 Å for the electron transport layer, and then Yb (ytterbium) was vacuum-deposited to a thickness of 10 Å for the electron injection layer.

[0092] Magnesium and silver were deposited on the electron injection layer in a weight ratio of 1:4 to a thickness of 150 Å to form a negative electrode, thereby completing an organic light emitting device. [ka]

[0093] During the above process, the deposition rate of the organic material was maintained at 0.4-0.7 Å / sec, the deposition rate of magnesium and silver was maintained at 2 Å / sec, and the vacuum degree during deposition was 2×10 -7 ~5×10 -6 Torr was maintained to fabricate an organic light-emitting device.

[0094] Examples 2 to 5, and Comparative Examples 1-1 to 3-4 Organic light emitting devices of Examples 2 to 5 and Comparative Examples 1-1 to 3-4 were fabricated using the same method as in Example 1, except that the host material was changed as shown in Table 2. In Comparative Examples 2-1 to 3-4, a simple mixture of two compounds was used as the host.

[0095] [Experimental Example] The organic light emitting devices manufactured in Examples 1 to 5 and Comparative Examples 1-1 to 3-4 were heat treated in an oven at 120° C. for 30 minutes, and then removed from the oven. A current was applied to measure the voltage, efficiency, and lifespan (T95). The results are shown in Table 2 below. At this time, the voltage and efficiency were measured at 10 mA / cm 2 The T95 value was measured at a current density of 20 mA / cm. 2 means the time (hr) until the initial brightness decreases to 95%.

[0096] [Table 2]

[0097] A compound represented by chemical formula 1 and a compound represented by chemical formula 2 are organic Alloy The organic light-emitting device was manufactured using the above-mentioned compound as a host for the light-emitting layer of the organic light-emitting device. As a result, the organic light-emitting device exhibited low voltage and high efficiency characteristics compared to materials having a structure different from that of Chemical Formula 1 or Chemical Formula 2. Alloy As a result of producing the mixture, it was confirmed that the life span was increased compared to the simple mixture. [Explanation of symbols]

[0098] 1 Board 2 Positive electrode 3. Light-emitting layer 4 Negative electrode 5. Hole injection layer 6. Hole transport layer 7 Electron blocking layer 8 Hole Blocking Layer 9 Electron transport layer 10 Electron injection layer

Claims

1. positive electrode; A negative electrode; and a light-emitting layer between the positive electrode and the negative electrode, The light-emitting layer includes an organic alloy of a compound represented by the following Chemical Formula 1 and a compound represented by the following Chemical Formula 2: The organic alloy is a result of pretreatment of two or more single organic compounds to have chemical interactions between the single organic compounds, forming an organic light-emitting device: [Chemical formula 1] 【Chemistry 1】 In the above Chemical Formula 1, A is a benzene ring fused to two adjacent rings; X 1 , X 2 and X 3 are N, Ar 1 and Ar 2 are each independently phenyl, biphenylyl, terphenylyl, dibenzofuranyl, dibenzothiophenyl, or dimethylfluorenyl, wherein said phenyl, biphenylyl, terphenylyl, dibenzofuranyl, dibenzothiophenyl, or dimethylfluorenyl is unsubstituted or substituted with deuterium; Ar 3 is an unsubstituted or deuterium-substituted aryl having 6 to 60 carbon atoms; or an unsubstituted or deuterium-substituted heteroaryl having 2 to 60 carbon atoms and containing at least one selected from the group consisting of N, O, and S, R 1 are each independently hydrogen; or deuterium; n1 is an integer from 1 to 10, [Chemical formula 2] 【Chemistry 2】 In the above Chemical Formula 2, Ar 4 and Ar 5 are each independently phenyl, biphenylyl, biphenylyl substituted with one methyl, terphenylyl, dimethylfluorenyl, dimethylfluorenylphenyl, dibenzofuranyl, dibenzothiophenyl, dibenzofuranylphenyl, or dibenzothiophenylphenyl; the phenyl, biphenylyl, biphenylyl substituted with one methyl, terphenylyl, dimethylfluorenyl, dimethylfluorenylphenyl, dibenzofuranyl, dibenzothiophenyl, dibenzofuranylphenyl, or dibenzothiophenylphenyl being unsubstituted or substituted with deuterium; R 2 are each independently hydrogen; or deuterium; Ar 4 and Ar 5 At least one of R is substituted with one or more deuterium atoms. 2 at least one of is deuterium, n2 is an integer from 1 to 10.

2. The compound represented by Chemical Formula 1 is represented by any one of Chemical Formulas 1-1 to 1-4 below, 【Chemistry 3】 In the above Chemical Formula 1-1 to Chemical Formula 1-4, X 1 , X 2 , X 3 , Ar 1 ~Ar 3 , R 1 , and n1 are as defined in claim 1.

3. Ar 1 and Ar 2 2. The organic light-emitting device according to claim 1, wherein each independently is phenyl, biphenylyl, terphenylyl, dibenzofuranyl, dibenzothiophenyl, dimethylfluorenyl, or phenyl substituted with five deuterium atoms.

4. Ar 1 and Ar 2 Each of the organic light-emitting devices according to claim 1 is independently any one selected from the group consisting of: 【Chemistry 4】 。

5. Ar 3 The organic light-emitting device according to claim 1, wherein is an unsubstituted or deuterium-substituted aryl having 6 to 20 carbon atoms.

6. Ar 3 2. The organic light-emitting element according to claim 1, wherein is phenyl, biphenylyl, terphenylyl, phenyl substituted with 5 deuterium atoms, or terphenylyl substituted with 5 to 13 deuterium atoms.

7. Ar 3 is any one selected from the group consisting of the following: 【Chemistry 5】 。

8. The organic light-emitting device according to claim 1 , wherein the compound represented by Chemical Formula 1 is any one selected from the group consisting of: 【Chemistry 6】 【Chemistry 7】 【Chemistry 8】 【Chemistry 9】 【Chemistry 10】 【Chemistry 11】 【Chemistry 12】 。

9. The organic light-emitting device according to claim 1, wherein the compound represented by Chemical Formula 2 is any one selected from the group consisting of: 【Chemistry 13】 In the above group, a+b+c+d+e is an integer from 1 to 28, 【Chemistry 14】 In the above group, a+b+c+d+e+f is an integer from 1 to 32, 【Chemistry 15】 In the above group, a+b+c+d is an integer from 1 to 26, 【Chemistry 16】 【Chemistry 17】 【Chemistry 18】 【Chemistry 19】 【Chemistry 20】 In the above group, a+b+c+d+e is an integer from 1 to 30, 【Chemistry 21】 In the above group, a+b+c+d is an integer from 1 to 32, 【Chemical 22】 【Chemistry 23】 In the above group, a+b+c+d+e is an integer from 1 to 36, 【Chemistry 24】 In the above group, a+b+c+d+e is an integer from 1 to 30, 【Chemistry 25】 In the above group, a+b+c+d+e is an integer from 1 to 32, 【Chemistry 26】 In the above group, a+b+c+d+e is an integer from 1 to 36.

Citation Information

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