Organic light-emitting devices

Abstract

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

Description

[Technical Field]

[0001] [CROSS-REFERENCE TO RELATED APPLICATIONS] This application claims the benefit of priority based on Korean Patent Application No. 10-2021-0097800, filed on July 26, 2021, and all contents disclosed in the documents of that Korean patent application 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 utilizing 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, much research is being conducted on these devices.

[0004] Organic light-emitting devices generally have a structure including an anode, an anode, and an organic material layer between the anode and the cathode. To enhance the efficiency and safety of organic light-emitting devices, the organic material layer often has a multi-layer structure composed of different materials, such as a hole injection layer, a hole transport layer, an emission layer, an electron transport layer, and an electron injection layer. In such an organic light-emitting device, when a voltage is applied between the two electrodes, holes are injected from the anode and electrons are injected from the anode into the organic material layer. When the injected holes and electrons come into contact, excitons are formed. When these excitons return to their ground state, light is emitted.

[0005] In the above organic light emitting devices, there is a continuing demand for the development of organic light emitting devices with 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 of a compound represented by the following chemical formula 1 and a compound represented by the following chemical formula 2: Alloy An organic light-emitting device, comprising: [Chemical formula 1] [ka] In the above Chemical Formula 1, X1, X2, and X3 are each independently CH or N, and at least one of X1, X2, and X3 is N; Ar1 and Ar2 each independently represent 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; Y is O, S, or CRR'; wherein R and R' are each independently a substituted or unsubstituted alkyl having 1 to 60 carbon atoms; R1 is 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, Ar3 and Ar4 are each independently a substituted or unsubstituted aryl having 6 to 12 carbon atoms; or a substituted or unsubstituted heteroaryl having 2 to 12 carbon atoms containing at least one selected from the group consisting of N, O, and S; R2 and R3 are each 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 Ar3 and Ar4 is substituted with one or more deuterium atoms, or at least one of R2 and R3 is deuterium; n2 and n3 each independently represent an integer of 1 to 7. [Effects 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 the light-emitting layer. Alloy By including the compound (I), it is possible to improve the efficiency, reduce the driving voltage and / or improve the life characteristics of the organic light emitting device. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a diagram showing an example of an organic light-emitting device comprising a substrate 1, a positive electrode 2, a light-emitting layer 3, and a negative electrode 4. FIG. [Figure 2] FIG. 1 shows an example of an organic light-emitting device comprising 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 INVENTION

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

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

[0013] As used herein, the term "substituted or unsubstituted" refers to a group selected from the group consisting of deuterium, halogen, nitrile, nitro, hydroxy, carbonyl, ester, imide, amino, phosphine oxide, alkoxy, aryloxy, alkylthioxy, arylthioxy, alkylsulfoxy, arylsulfoxy, silyl, boron, alkyl, cycloalkyl, alkenyl, aryl, aralkyl, aralkenyl, alkylaryl, alkylamine, aralkylamine, heteroarylamine, arylamine, arylphosphine, or heterocyclic groups containing one or more N, O, and S atoms, or a group in which two or more of the above-listed substituents are linked together. For example, a "substituent linked to two or more substituents" may be a biphenyl group. That is, a biphenyl group may be an aryl group or may be interpreted as a substituent in which two phenyl groups are linked together.

[0014] In this specification, the number of carbon atoms in the carbonyl group is not particularly limited, but preferably is 1 to 40. Specifically, the carbonyl group may have a substituent having the following structure, but is not limited thereto. [ka]

[0015] In this specification, the oxygen atom 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 ester group may be a substituent having the following structural formula, but is not limited to these. [ka]

[0016] In this specification, the number of carbon atoms of the imide group is not particularly limited, but preferably is 1 to 25. Specifically, the imide group may have a substituent having the following structure, but is not limited thereto. [ka]

[0017] In this specification, specific examples of silyl groups include, but are not limited to, trimethylsilyl, triethylsilyl, t-butyldimethylsilyl, vinyldimethylsilyl, propyldimethylsilyl, triphenylsilyl, diphenylsilyl, and phenylsilyl groups.

[0018] In this specification, specific examples of the boron group include, but are not limited to, a trimethyl boron group, a triethyl boron group, a t-butyldimethyl boron group, a triphenyl boron group, and a phenyl boron group.

[0019] As used herein, examples of halogen groups include fluorine, chlorine, bromine, or iodine.

[0020] 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 in the alkyl group is 1 to 20. According to another embodiment, the number of carbon atoms in the alkyl group is 1 to 10. According to another embodiment, the number of carbon atoms in 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-methylbutyl, 1-ethylbutyl, 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-ethylpropyl, 1,1-dimethylpropyl, isohexyl, 4-methylhexyl, 5-methylhexyl, and the like.

[0021] 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 in the alkenyl group is 2 to 20. According to another embodiment, the number of carbon atoms in the alkenyl group is 2 to 10. According to yet another embodiment, the number of carbon atoms in 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.

[0022] In the present specification, the cycloalkyl group is not particularly limited, but preferably has 3 to 60 carbon atoms. According to one embodiment, the cycloalkyl group has 3 to 30 carbon atoms. According to another embodiment, the cycloalkyl group has 3 to 20 carbon atoms. According to another embodiment, the cycloalkyl group has 3 to 6 carbon atoms. Specific examples of the cycloalkyl group 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.

[0023] In this 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.

[0024] In this 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.

[0025] In this specification, the heterocyclic group is a heterocyclic group containing one or more heteroelements selected from O, N, Si and S, and is not particularly limited in number of carbon atoms, 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 groups.

[0026] In this specification, the aryl group of the aralkyl group, aralkenyl group, alkylaryl group, and arylamine group is applicable to the aryl group. In this specification, the alkyl group of the aralkyl group, alkylaryl group, and alkylamine group is applicable to the alkyl group. In this specification, the heteroaryl of the heteroarylamine group is applicable to the heteroaryl group. In this specification, the alkenyl group of the aralkenyl group is applicable to the alkenyl group. In this specification, the aryl group of the arylene group is applicable to the aryl group, except that it is a divalent group. In this specification, the heteroarylene group is applicable to the heterocyclic group, except that it is a divalent group. In this specification, the hydrocarbon ring is not a monovalent group, but is formed by the bonding of two substituents, and the aryl group or cycloalkyl group is applicable to the heterocyclic group, except that it is not a monovalent group, but is formed by the bonding of two substituents. In this specification, the heterocycle is not a monovalent group, but is formed by the bonding of two substituents, and the heterocyclic group is applicable to the heterocyclic group.

[0027] On the other hand, in the present invention, Alloy The term "organic alloy" refers to a result of pre-treatment of two or more single organic compounds, which may result in 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.

[0028] The present invention will be described in detail below for each component.

[0029] Positive and negative electrodes The positive electrode and negative electrode used in the present invention refer to electrodes used in an organic light-emitting device.

[0030] The cathode material preferably has a high work function to facilitate hole injection into the organic layer. Specific examples of the cathode 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 SnO:Sb; and conductive polymers such as poly(3-methylthiophene), poly[3,4-(ethylene-1,2-dioxy)thiophene] (PEDOT), polypyrrole, and polyaniline.

[0031] The negative electrode material is preferably a material with a small work function so as to facilitate electron injection 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 LiO / Al.

[0032] 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.

[0033] The hole injection layer is a layer that injects holes from the electrode, and the hole injection material preferably has the ability to transport holes, has excellent hole injection effect from the cathode, has excellent hole injection effect on the light-emitting layer or light-emitting material, prevents excitons generated in the light-emitting layer from migrating to the electron injection layer or electron injection material, and has excellent thin-film formation ability. Furthermore, it is preferable that the HOMO (highest occupied molecular orbital) of the hole injection material is between the work function of the cathode material and the HOMO of the surrounding organic layer.

[0034] 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.

[0035] 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).

[0036] The hole transport layer receives holes from the anode or the hole injection layer and transports them to the light emitting layer. As the hole transport material, a material that can receive holes from the anode or the hole injection layer and transfer them to the light emitting layer and has high mobility for holes is preferred.

[0037] Specific examples of the hole transport material include, but are not limited to, arylamine-based organic compounds, conductive polymers, and block copolymers having both conjugated and non-conjugated portions.

[0038] 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.

[0039] The electron blocking layer, also called an electron inhibiting layer, is a layer disposed between the hole transport layer and the light emitting layer to prevent electrons injected from the anode from passing to the hole transport layer without being recombined in the light emitting layer. The electron blocking layer is preferably made of a material having a smaller electron affinity than the electron transport layer.

[0040] Light-emitting layer The light-emitting layer used in the present invention means a layer capable of emitting light in the visible region by combining holes and electrons transferred from the positive electrode and the negative electrode. Generally, the light-emitting layer includes a host material and a dopant material. In the present invention, the light-emitting layer 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 used by the host.

[0041] Preferably, Ar1 may be a substituted or unsubstituted aryl having 6 to 20 carbon atoms, more preferably phenyl, biphenylyl, terphenylyl, or phenyl substituted with five deuterium atoms. Most preferably, Ar1 may be any one selected from the group consisting of: [ka]

[0042] Preferably, Ar2 may be a substituted or unsubstituted aryl having 6 to 20 carbon atoms, more preferably, Ar2 may be phenyl or biphenylyl. Most preferably, Ar2 is phenyl or [ka] may be.

[0043] Preferably, R and R' may each independently be a substituted or unsubstituted alkyl having 1 to 10 carbon atoms, and more preferably, R and R' may each be methyl.

[0044] Preferably, R1 may be 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, R1 may be hydrogen or deuterium.

[0045] Representative examples of the compound represented by Formula 1 are as follows: [ka] [ka] [ka] [ka] [ka]

[0046] The compound represented by Chemical Formula 1 can be prepared by the following method, for example, Reaction Scheme 1, and the remaining compounds can also be prepared by similar methods. [Reaction Scheme 1] [ka]

[0047] In the reaction formula 1, X1, X2, X3, Ar1, Ar2, 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 groups for the amine substitution reaction can be changed according to those known in the art. The preparation method is more specifically exemplified in the preparation examples described below.

[0049] Preferably, the compound represented by Chemical Formula 2 can be represented by the following Chemical Formula 2-1: [Chemical formula 2-1] [ka] In the above chemical formula 2-1, Ar3, Ar4, R2, R3, n2, and n3 are as defined in Chemical Formula 2 above.

[0050] Preferably, Ar3 and Ar4 may each independently be phenyl, biphenylyl, naphthyl, dimethylfluorenyl, dibenzofuranyl, or dibenzothiophenyl, wherein the phenyl, biphenylyl, naphthyl, dimethylfluorenyl, dibenzofuranyl, or dibenzothiophenyl may be unsubstituted or substituted with deuterium (D).

[0051] R2 and R3 may each independently be 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, R2 and R3 may each independently be hydrogen, deuterium, or phenyl, and the phenyl may be unsubstituted or substituted with 1 to 5 deuterium atoms.

[0052] Representative examples of the compound represented by Formula 2 are as follows: [ka] In the compound, a+b+c+d is 1 to 24, [ka] In the above group, a+b+c+d+e is 1 to 28, [ka] In the above group, a+b+c+d+e+f is 1 to 32, [ka] In the above group, a+b+c+d+e is 1 to 30, [ka] In the above group, a+b+c+d is 1 to 26, [ka] [ka] In the above group, a+b+c+d+e is 1 to 30, [ka] In the above group, a+b+c+d+e+f is 1 to 32, [ka] In the above group, a+b+c+d is between 1 and 32, [ka] In the above group, a+b+c+d+e is 1 to 36.

[0053] The compound represented by Chemical Formula 2 can be prepared by the following method, for example, Reaction Scheme 2, and the remaining compounds can also be prepared by similar methods. [Reaction Scheme 2] [ka]

[0054] In the reaction formula 2, Ar3, Ar4, R2, R3, n2, and n3 are as defined in the chemical formula 2, and Z2 is a halogen, preferably Z2 is 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 groups 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 below.

[0056] Preferably, the organic Alloy 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, 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 organic light-emitting devices. Examples include aromatic amine derivatives, styrylamine compounds, boron complexes, fluoranthene compounds, and metal complexes. Specific examples of aromatic amine derivatives include fused aromatic ring derivatives having a substituted or unsubstituted arylamino group, such as pyrene, anthracene, chrysene, and periplanthene. Specific examples of styrylamine compounds include substituted or unsubstituted arylamines substituted with at least one arylvinyl group, and the substituted or unsubstituted group may be one or more substituents selected from the group consisting of aryl groups, silyl groups, alkyl groups, cycloalkyl groups, and arylamino groups. Specific examples include, but are not limited to, styrylamines, styryldiamines, styryltriamines, and styryltetraamines. 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, also called a hole blocking layer, is a layer disposed between the electron transport layer and the light emitting layer to prevent holes injected from the anode from passing to the electron transport layer without recombining in the light emitting layer. A material with high ionization energy is preferred 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 receives electrons from the anode or the electron injection layer formed on the anode, transports the electrons to the light-emitting layer, and inhibits the transfer of holes from the light-emitting layer. As the electron transport material, a material that can efficiently receive electrons injected from the anode and transfer them to the light-emitting layer and has high electron mobility is preferred.

[0062] Specific examples of the electron transport material include, but are not limited to, Al complexes of 8-hydroxyquinoline; complexes containing Alq; organic radical compounds; and hydroxyflavone-metal complexes. The electron transport layer can be used with any desired cathode material, as used in the prior art. In particular, examples of suitable cathode materials are conventional materials with low work functions followed by an aluminum or silver layer. Specific examples include 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 include an electron injection layer on the light-emitting layer (or on the electron transport layer, if present) as needed.

[0064] The electron injection layer is a layer that injects electrons from the 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, has an excellent electron injection effect on the light-emitting layer or the light-emitting material, prevents excitons generated in the light-emitting layer from moving to the hole injection layer, and has excellent thin-film formation ability.

[0065] Specific examples of materials 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 compounds include, but are not limited to, 8-hydroxyquinolinatolithium, 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 devices The structures of organic light-emitting devices according to the present invention are shown in Figures 1 and 2. Figure 1 shows an example of an organic light-emitting device comprising a substrate 1, a positive electrode 2, an emitting layer 3, and a negative electrode 4. Figure 2 shows an example of an organic light-emitting device comprising a substrate 1, a positive electrode 2, a hole injection layer 5, a hole transport layer 6, an electron blocking layer 7, an 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 can be fabricated by sequentially stacking the above-described components. To fabricate the device, a metal, conductive metal oxide, or alloy thereof can be deposited on a substrate using a physical vapor deposition (PVD) method, such as sputtering or e-beam evaporation, to form the cathode. The above-described layers are then formed on the cathode, and the cathode material is then deposited on top of the cathode material. Alternatively, an organic light emitting device can be fabricated by sequentially depositing the cathode material on a substrate in the reverse order of the above-described structure (see WO 2003 / 012890). The light emitting layer can be formed by depositing the host and dopant by a solution coating method, rather than by vacuum deposition. Solution coating methods include, but are not limited to, spin coating, dip coating, doctor blading, inkjet printing, screen printing, spraying, and roll coating.

[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 luminous 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: Production of Compound] Preparation Example 1-1: Synthesis of Compound 1-1 Step 1) Synthesis of compound 1-1-a [ka]

[0072] In a nitrogen atmosphere, 11,12-dihydroindolo[2,3-a]carbazole (15.0 g, 58.5 mmol) and bromobenzene (10.1 g, 64.4 mmol) were added to 300 mL of toluene and stirred under reflux. 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 10 hours of reaction, the mixture was cooled to room temperature, and the organic layer was separated using chloroform and water. The organic layer was then distilled. This was further dissolved in chloroform and washed twice with water. The organic layer was separated, stirred with anhydrous magnesium sulfate, filtered, and the filtrate was distilled under reduced pressure. The concentrated compound was purified by silica gel column chromatography to produce 12.8 g of compound 1-1-a (yield 66%, MS: [M+H] + =333).

[0073] Step 2) Synthesis of Compound 1-1 [ka]

[0074] In a nitrogen atmosphere, compound 1-1-a (15.0 g, 45.1 mmol) and 2-chloro-4-(dibenzo[b,d]furan-3-yl)-6-phenyl-1,3,5-triazine (17.8 g, 49.6 mmol) were added to 300 mL of toluene and stirred under reflux. Sodium tert-butoxide (6.5 g, 67.7 mmol) and bis(tri-tert-butylphosphine)palladium(0) (0.7 g, 1.4 mmol) were then added. After 12 hours of reaction, the mixture was cooled to room temperature and the organic layer was separated using chloroform and water. The organic layer was then distilled. This was further dissolved in chloroform and washed twice with water. The organic layer was then separated and added to anhydrous magnesium sulfate, stirred, filtered, and the filtrate was distilled under reduced pressure. The concentrated compound was purified by silica gel column chromatography and then purified by sublimation to produce 14.5 g of compound 1-1 (yield 49%, MS: [M+H] +=747).

[0075] Preparation Example 1-2: Synthesis of Compound 1-2 [ka]

[0076] Compound 1-2 was prepared in the same manner as in Preparation Example 1-1, except that bromobenzene was replaced with 3-bromo-1,1'-biphenyl and 2-chloro-4-(dibenzo[b,d]furan-3-yl)-6-phenyl-1,3,5-triazine was replaced with 2-chloro-4-(dibenzo[b,d]thiophen-4-yl)-6-phenyl-1,3,5-triazine (MS [M+H] + =757).

[0077] Preparation Example 1-3: Synthesis of Compound 1-3 [ka]

[0078] Compound 1-3 was prepared in the same manner as in Preparation Example 1-1, except that 2-chloro-4-(dibenzo[b,d]furan-3-yl)-6-phenyl-1,3,5-triazine was replaced with 2-([1,1'-biphenyl]-4-yl)-4-chloro-6-(9,9-dimethyl-9H-fluoren-4-yl)-1,3,5-triazine (MS [M+H] + =717).

[0079] Preparation Example 1-4: Synthesis of Compound 1-4 [ka]

[0080] Compound 1-4 was prepared in the same manner as in Preparation Example 1-1, except that 11,12-dihydroindolo[2,3-a]carbazole was replaced with 11,12-dihydroindolo[2,3-a]carbazole-1,3,4,5,6,8,10-d7 (MS [M+H] + =662).

[0081] Preparation Example 1-5: Synthesis of Compound 2-1 Step 1) Synthesis of compound 2-1-a [ka]

[0082] Under a nitrogen atmosphere, 9-([1,1'-biphenyl]-4-yl)-3-bromo-9H-carbazole (15.0 g, 37.7 mmol) and 9-phenyl-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-9H-carbazole (15.3 g, 41.4 mmol) were added to 300 mL of THF and stirred under reflux. Potassium carbonate (20.8 g, 150.6 mmol) dissolved in 62 mL of water was then added and stirred thoroughly, followed by the addition of tetrakis(triphenylphosphine)palladium(0) (1.3 g, 1.1 mmol). After 9 hours of reaction, the mixture was cooled to room temperature, the organic and aqueous layers were separated, and the organic layer was distilled. This was then dissolved in chloroform and washed twice with water. The organic layer was separated, added to anhydrous magnesium sulfate, and stirred. The filtrate was then filtered and distilled under reduced pressure. The concentrated compound was purified by silica gel column chromatography to produce 13.5 g of compound 2-1-a (yield 64%, MS: [M+H] + =562).

[0083] Step 2) Synthesis of Compound 2-1 [ka]

[0084] Compound 2-1-a (10.0 g, 17.8 mmol), PtO (1.2 g, 5.4 mmol), and 89 ml of DO were placed in a shaker tube, sealed, and heated at 250 °C and 600 psi for 12 hours. Upon completion of the reaction, chloroform was added and the reaction mixture was transferred to a separatory funnel for extraction. The extract was dried over anhydrous magnesium sulfate and concentrated. The sample was purified by silica gel column chromatography and then purified by sublimation to produce 3.9 g of compound 2-1 (yield 38%, MS: [M+H]). + =580).

[0085] Preparation Example 1-6: Synthesis of Compound 2-2 Step 1) Synthesis of compound 2-2-a [ka]

[0086] 9-([1,1'-biphenyl]-4-yl)-3-bromo-9H-carbazole (10 g, 25.1 mmol), PtO2 (1.7 g, 7.5 mmol), and 126 mL of DO were placed in a shaker tube, sealed, and heated at 250 °C and 600 psi for 12 hours. Upon completion of the reaction, chloroform was added and the reaction mixture was transferred to a separatory funnel for extraction. The extract was dried over anhydrous magnesium sulfate and concentrated. The sample was purified by silica gel column chromatography to produce 7.9 g of compound 2-2-a (yield 77%, MS: [M+H]). + =409).

[0087] Step 2) Synthesis of Compound 2-2 [ka]

[0088] Compound 2-2-a (15.0 g, 36.7 mmol) and 9-([1,1'-biphenyl]-2-yl)-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-9H-carbazole (18.0 g, 40.4 mmol) were added to 300 mL of THF under a nitrogen atmosphere and stirred under reflux. Potassium carbonate (20.3 g, 146.9 mmol) dissolved in 61 mL of water was then added and stirred thoroughly, followed by the addition of tetrakis(triphenylphosphine)palladium(0) (1.3 g, 1.1 mmol). After 12 hours of reaction, the mixture was cooled to room temperature, the organic and aqueous layers were separated, and the organic layer was distilled. This was then dissolved in chloroform and washed twice with water. The organic layer was separated, added to anhydrous magnesium sulfate, and stirred. The mixture was then filtered and the filtrate was distilled under reduced pressure. The concentrated compound was purified by silica gel column chromatography and then purified by sublimation to produce 11.6 g of compound 2-2 (yield 49%, MS: [M+H] + =648)

[0089] Preparation Example 1-7: Synthesis of Compound 2-3 Step 1) Synthesis of compound 2-3-a [ka]

[0090] Under a nitrogen atmosphere, 3-bromo-9H-carbazole (15.0 g, 60.9 mmol) and 9-phenyl-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-9H-carbazole (24.8 g, 67 mmol) were added to 300 mL of THF and stirred under reflux. Potassium carbonate (33.7 g, 243.8 mmol) dissolved in 101 mL of water was then added and stirred thoroughly, followed by the addition of tetrakis(triphenylphosphine)palladium(0) (2.1 g, 1.8 mmol). After 11 hours of reaction, the mixture was cooled to room temperature, the organic and aqueous layers were separated, and the organic layer was distilled. This was then dissolved in chloroform and washed twice with water. The organic layer was separated, added to anhydrous magnesium sulfate, stirred, filtered, and the filtrate was distilled under reduced pressure. The concentrated compound was purified by silica gel column chromatography to produce 16.7 g of compound 2-3-a (yield 67%, MS: [M+H] + =410).

[0091] Step 2) Synthesis of compound 2-3-b [ka]

[0092] Compound 2-3-a (10.0 g, 24.5 mmol), PtO (1.7 g, 7.3 mmol), and 122 ml of DO were placed in a shaker tube, sealed, and heated at 250 °C and 600 psi for 12 hours. Upon completion of the reaction, chloroform was added and the reaction mixture was transferred to a separatory funnel for extraction. The extract was dried over anhydrous magnesium sulfate and concentrated. The sample was purified by silica gel column chromatography to produce 9.1 g of compound 2-3-b (yield 88%, MS: [M+H]). + =423).

[0093] Step 3) Synthesis of Compound 2-3 [ka]

[0094] Compound 2-3-b (15.0 g, 36.7 mmol) and 2-bromo-9,9-dimethyl-9H-fluorene (11.0 g, 40.4 mmol) were added to 300 mL of toluene under a nitrogen atmosphere and stirred and refluxed. Sodium tert-butoxide (5.3 g, 55.1 mmol) and bis(tri-tert-butylphosphine)palladium(0) (0.6 g, 1.1 mmol) were then added. After 6 hours of reaction, the mixture was cooled to room temperature, and the organic layer was separated using chloroform and water. The organic layer was then distilled. This was further dissolved in chloroform and washed twice with water. The organic layer was separated, stirred with anhydrous magnesium sulfate, filtered, and the filtrate was distilled under reduced pressure. The concentrated compound was purified by silica gel column chromatography and then purified by sublimation to produce 9.5 g of compound 2-3 (yield 42%, MS: [M+H]). + =615).

[0095] Preparation Example 1-8: Synthesis of Compound 2-4 Step 1) Synthesis of compound 2-4-a [ka]

[0096] Under a nitrogen atmosphere, 3-bromo-9H-carbazole (15.0 g, 60.9 mmol) and 9-(phenyl-d5)-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-9H-carbazole (25.1 g, 67 mmol) were added to 300 mL of THF and stirred under reflux. Potassium carbonate (33.7 g, 243.8 mmol) dissolved in 101 mL of water was then added and stirred thoroughly, followed by the addition of tetrakis(triphenylphosphine)palladium(0) (2.1 g, 1.8 mmol). After 9 hours of reaction, the mixture was cooled to room temperature, the organic and aqueous layers were separated, and the organic layer was distilled. This was then dissolved in chloroform and washed twice with water. The organic layer was separated, added to anhydrous magnesium sulfate, stirred, filtered, and the filtrate was distilled under reduced pressure. The concentrated compound was purified by silica gel column chromatography to produce 16.1 g of compound 2-4-a (yield 64%, MS: [M+H] + =415).

[0097] Step 2) Synthesis of Compounds 2-4 [ka]

[0098] Compound 2-4-a (15.0 g, 36.3 mmol) and 2-bromodibenzo[b,d]furan (9.9 g, 39.9 mmol) were added to 300 mL of toluene under a nitrogen atmosphere and stirred and refluxed. Sodium tert-butoxide (5.2 g, 54.4 mmol) and bis(tri-tert-butylphosphine)palladium(0) (0.6 g, 1.1 mmol) were then added. After 11 hours of reaction, the mixture was cooled to room temperature, and the organic layer was separated using chloroform and water. The organic layer was then distilled. This was further dissolved in chloroform and washed twice with water. The organic layer was separated, stirred with anhydrous magnesium sulfate, filtered, and the filtrate was distilled under reduced pressure. The concentrated compound was purified by silica gel column chromatography and then purified by sublimation to produce 8.1 g of compound 2-4 (yield 38%, MS: [M+H] + =586).

[0099] [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. -2 The two mixtures were dissolved by increasing the temperature under a pressure of less than Torr, and after 1 hour, the mixture was cooled to room temperature to obtain a solid product. This product was crushed in a mixer to obtain a powdered organic compound. Alloy I got 1.

[0100] Production Examples 2-2 to 2-5, and Production Examples 2-A to 2-D The organic solvent was prepared in the same manner as in Preparation Example 2-1, except that the materials to be mixed were changed as shown in Table 1 below. Alloy 2~Organic Alloy 5, and organic Alloy A~Organic Alloy Compounds A-1, A-2, B-1 and B-2 in Table 1 below are as follows. [ka]

[0101] [Table 1]

[0102] [Example: Production of organic light-emitting element] Example 1 A glass substrate coated with a 1400Å-thick thin film of ITO (indium tin oxide) was placed in distilled water with detergent and ultrasonically cleaned. The detergent used was a product of Fischer Co., and the distilled water was distilled water that had been filtered through a Millipore Co. filter. After cleaning the ITO for 30 minutes, it was ultrasonically cleaned twice with distilled water for 10 minutes. After the distilled water cleaning, it 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 using oxygen plasma for 5 minutes before being transferred to a vacuum deposition device.

[0103] On the ITO transparent electrode thus prepared, 95 wt % of the following compound HT-A and 5 wt % of the following 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.

[0104] Then, the organic layer prepared in Preparation Example 2-1 was applied as a host material to a thickness of 350 Å on the electron blocking layer. Alloy The light-emitting layer was formed by vacuum deposition of 1 and the following compound GD, which was a dopant material, in a weight ratio of 92:8.

[0105] 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 the following compound Liq were thermally vacuum-deposited in a 1:1 weight ratio to a thickness of 300 Å for the electron-transporting layer, and then Yb was vacuum-deposited to a thickness of 10 Å for the electron-injecting layer.

[0106] On the electron injection layer, magnesium and silver were deposited in a weight ratio of 1:4 to a thickness of 150 Å to form a cathode, thereby completing an organic light emitting device. [ka]

[0107] 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 level during deposition was 2×10 -7 ~5×10 -6 The organic light-emitting device was fabricated under a constant pressure of torr.

[0108] 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.

[0109] [Experimental example: Evaluation of element characteristics] The organic light emitting devices fabricated 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, then removed and 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 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%.

[0110] [Table 2]

[0111] The compound represented by chemical formula 1 and the compound represented by chemical formula 2 are organic Alloyand used as a host for the light-emitting layer of an organic electroluminescent device. As a result, the 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 manufacturing the battery, it was confirmed that the battery exhibited characteristics of lower voltage, higher efficiency, and longer life compared to the battery using a simple mixture. [Explanation of symbols]

[0112] 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 pre-treatment of two or more single organic compounds to have chemical interactions between the single organic compounds. Organic light-emitting devices: [Chemical formula 1] 【Chemical 1】 In the above Chemical Formula 1, X １ , X ２ and X ３ are each independently CH or N, and X １ , X ２ and X ３ at least one of is N; Ar １ and Ar ２ 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, Y is O, S, or CRR′; wherein R and R' are each independently a substituted or unsubstituted alkyl having 1 to 60 carbon atoms; R １ is 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] 【Chemistry 45】 In the above Chemical Formula 2, Ar ３ and Ar ４ are each independently a substituted or unsubstituted aryl having 6 to 12 carbon atoms; or a substituted or unsubstituted heteroaryl having 2 to 12 carbon atoms containing at least one selected from the group consisting of N, O, and S, R ２ and R ３ are each 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, Ar ３ and Ar ４ At least one of R is substituted with one or more deuterium atoms, or ２ and R ３ at least one of is deuterium, n2 and n3 each independently represent an integer of 1 to 7.

2. Ar １ 2. The organic light-emitting device according to claim 1, wherein is phenyl, biphenylyl, terphenylyl, or phenyl substituted with five deuterium atoms.

3. Ar ２ The organic light-emitting device according to claim 1 , wherein is phenyl or biphenylyl.

4. 2. The organic light-emitting device of claim 1, wherein R and R' are each methyl.

5. R １ The organic light-emitting device according to claim 1 , wherein is hydrogen or deuterium.

6. 2. 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 11】 【Chemistry 12】 【Chemistry 13】 【Chemistry 14】 【Chemistry 15】 。

7. The compound represented by Chemical Formula 2 is the organic light-emitting device according to claim 1, which is represented by the following Chemical Formula 2-1: [Chemical formula 2-1] 【Chemistry 46】 In the above chemical formula 2-1, Ar ３ , Ar ４ , R ２ , R ３ , n2, and n3 are as defined in claim 1.

8. Ar ３ and Ar ４ are each independently phenyl, biphenylyl, naphthyl, dimethylfluorenyl, dibenzofuranyl, or dibenzothiophenyl; The organic light-emitting device of claim 1 , wherein the phenyl, biphenylyl, naphthyl, dimethylfluorenyl, dibenzofuranyl, or dibenzothiophenyl is unsubstituted or substituted with deuterium.

9. R ２ and R ３ are each independently hydrogen, deuterium, or phenyl; The organic light-emitting device according to claim 1, wherein the phenyl is unsubstituted or substituted with 1 to 5 deuterium atoms.

10. 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 47】 In the compound, a+b+c+d is 1 to 24, 【Chemistry 19】 In the above group, a+b+c+d+e is 1 to 28, 【Chemistry 20】 In the above group, a+b+c+d+e+f is 1 to 32, 【Chemical 21】 In the above group, a+b+c+d+e is 1 to 30, 【Chemical 22】 In the above group, a+b+c+d is 1 to 26, 【Chemical 23】 【Chemistry 24】 In the above group, a+b+c+d+e is 1 to 30, 【Chemistry 25】 In the above group, a+b+c+d+e+f is 1 to 32, 【Chemical 26】 In the above group, a+b+c+d is 1 to 32, 【Chemical 27】 In the above group, a+b+c+d+e is 1 to 36.

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