Organic light-emitting devices

Abstract

The present invention provides an organic light-emitting device, which includes: an anode; a cathode disposed opposite to the anode; a light-emitting layer between the anode and the cathode; a hole transport region between the anode and the light-emitting layer; and an electron transport region between the light-emitting layer and the cathode, wherein the electron transport region contains a compound represented by Chemical Formula 1, and the light-emitting layer contains a compound represented by Chemical Formula 2.

Description

Technical Field

[0001] This application claims the priority based on Korean Patent Application No. 10-2019-0055219 filed on May 10, 2019, and incorporates all the contents disclosed in the document of the Korean Patent Application as a part of this specification.

[0002] The invention relates to an organic light emitting device with low driving voltage, high luminous efficiency and excellent lifespan. Background Art

[0003] Generally speaking, the organic light-emitting phenomenon refers to the phenomenon of converting electrical energy into light energy using organic substances. Organic light-emitting devices using the organic light-emitting phenomenon have wide viewing angles, excellent contrast, fast response time, and excellent brightness, driving voltage, and response speed characteristics, so a lot of research is being carried out.

[0004] An organic light-emitting device generally has a structure including an anode and a cathode and an organic layer located between the anode and the cathode. In order to improve the efficiency and stability of the organic light-emitting device, the organic layer is usually formed by a multilayer structure composed of different substances, for example, a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, an electron injection layer, etc. For such an organic light-emitting device structure, if a voltage is applied between the two electrodes, holes are injected from the anode into the organic layer, and electrons are injected from the cathode into the organic layer. When the injected holes and electrons meet, excitons are formed, and when the excitons transition back to the ground state, light is emitted.

[0005] As for organic substances used for organic light-emitting devices as described above, development of new materials continues to be required.

[0006] Prior art literature

[0007] Patent Literature

[0008] (Patent Document 0001) Korean Patent Publication No. 10-2000-0051826 Summary of the invention

[0009] Technical issues

[0010] The invention relates to an organic light emitting device with low driving voltage, high luminous efficiency and excellent lifespan.

[0011] Solution to the problem

[0012] In order to solve the above-mentioned problems, the present invention provides the following organic light-emitting device.

[0013] The organic light emitting device according to the present invention comprises:

[0014] anode;

[0015] a cathode disposed opposite to the anode;

[0016] A light-emitting layer is provided between the anode and the cathode;

[0017] A hole transport region is provided between the anode and the light-emitting layer; and

[0018] An electron transport region is provided between the light-emitting layer and the cathode,

[0019] The electron transport region includes a first compound represented by the following Chemical Formula 1:

[0020] The light-emitting layer includes a second compound represented by the following chemical formula 2:

[0021] [Chemical formula 1]

[0022]

[0023] In the above chemical formula 1,

[0024] X1 to X3 are each independently N or CH, and at least one of X1 to X3 is N,

[0025] L1 is a single bond; substituted or unsubstituted C 6-60 or a substituted or unsubstituted C containing any one or more heteroatoms selected from N, O and S 2-60 Heteroarylene,

[0026] Ar1 and Ar2 are each independently substituted or unsubstituted C 6-60 Aryl; or a substituted or unsubstituted C containing any one or more heteroatoms selected from N, O and S 2-60 Heteroaryl,

[0027] [Chemical formula 2]

[0028]

[0029] In the above chemical formula 2,

[0030] L2 and L3 are each independently a single bond; substituted or unsubstituted C 6-60 or a substituted or unsubstituted C containing any one or more heteroatoms selected from N, O and S 2-60 Heteroarylene,

[0031] Ar3 and Ar4 are each independently substituted or unsubstituted C 6-60 Aryl; or a substituted or unsubstituted C containing any one or more heteroatoms selected from N, O and S 2-60 Heteroaryl,

[0032] R is substituted or unsubstituted C 6-60 an aryl group, a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted dibenzofuranyl group, or a substituted or unsubstituted dibenzothiophenyl group.

[0033] Effects of the Invention

[0034] The above-mentioned organic light-emitting device includes compounds of specific structures in the light-emitting layer and the electron transport region, respectively, and thus can exhibit low driving voltage, high light-emitting efficiency, and long life characteristics. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 An example of an organic light-emitting device composed of a substrate 10 , an anode 20 , a hole transport region 30 , a light-emitting layer 40 , an electron transport region 50 , and a cathode 60 is illustrated.

[0036] Figure 2 The figure shows an example of an organic light-emitting device composed of a substrate 10, an anode 20, a hole transport region 30, a light-emitting layer 40, an electron transport region 50 and a cathode 60, wherein the hole transport region 30 comprises a hole injection layer 31, a hole transport layer 33 and an electron blocking layer 35 stacked in sequence from the anode 20, and the electron transport region 50 comprises a hole blocking layer 51, an electron transport layer 53 and an electron injection layer 55 stacked in sequence from the light-emitting layer 40. DETAILED DESCRIPTION

[0037] In the following, the present invention will be described in more detail to help understanding the present invention.

[0038] In this manual, It represents the bond to other substituents.

[0039] In the present specification, the term "substituted or unsubstituted" refers to a group selected from deuterium; a halogen group; a cyano group; a nitro group; a hydroxyl group; a carbonyl group; an ester group; an imide group; an amino group; a phosphine oxide group; an alkoxy group; an aryloxy group; an alkylthio group ( alkyl thioxy); arylthio aryl thioxy); alkylsulfonyl ( alkyl sulfoxy); arylsulfonyl ( The present invention may be substituted or unsubstituted with one or more substituents of heteroaryl groups containing one or more N, O and S atoms, or substituted or unsubstituted with a substituent formed by connecting two or more substituents among the substituents exemplified above. For example, "a substituent formed by connecting two or more substituents" may be a biphenyl group. That is, the biphenyl group may be an aryl group, and may also be interpreted as a substituent formed by connecting two phenyl groups.

[0040] In the present specification, the number of carbon atoms in the carbonyl group is not particularly limited, but preferably the number of carbon atoms is 1 to 40. Specifically, the group may have the following structure, but is not limited thereto.

[0041]

[0042] In the present specification, in the ester group, the oxygen of the ester group may be substituted by 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 group may be a group of the following structural formula, but is not limited thereto.

[0043]

[0044] In the present specification, the number of carbon atoms in the imide group is not particularly limited, but the number of carbon atoms is preferably 1 to 25. Specifically, the group may have the following structure, but is not limited thereto.

[0045]

[0046] In the present specification, specific examples of the silyl group include trimethylsilyl, triethylsilyl, tert-butyldimethylsilyl, vinyldimethylsilyl, propyldimethylsilyl, triphenylsilyl, diphenylsilyl, and phenylsilyl, but are not limited thereto.

[0047] In the present specification, specific examples of the boryl group include trimethylboryl, triethylboryl, tert-butyldimethylboryl, triphenylboryl, and phenylboryl, but are not limited thereto.

[0048] In the present specification, as examples of the halogen group, there are fluorine, chlorine, bromine or iodine.

[0049] In the present 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 the alkyl group include methyl, ethyl, propyl, n-propyl, isopropyl, butyl, n-butyl, isobutyl, tert-butyl, sec-butyl, 1-methyl-butyl, 1-ethyl-butyl, pentyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, hexyl, n-hexyl, 1-methylpentyl, 2-methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl, 2-ethylbutyl, heptyl, n-heptyl, 1-methylhexyl, cyclopentylmethyl, cyclohexylmethyl, octyl, n-octyl, tert-octyl, 1-methylheptyl, 2-ethylhexyl, 2-propylpentyl, n-nonyl, 2,2-dimethylheptyl,

[0050] 1-ethyl-propyl, 1,1-dimethyl-propyl, isohexyl, 2-methylpentyl, 4-methylhexyl, 5-methylhexyl, etc., but are not limited thereto.

[0051] In the present 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 another embodiment, the number of carbon atoms of the alkenyl group is 2 to 10. According to another embodiment, the number of carbon atoms of the alkenyl group is 2 to 6. As specific examples, there are 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-(naphthalene-1-yl)vinyl-1-yl, 2,2-bis(diphenyl-1-yl)vinyl-1-yl, stilbene, styryl, etc., but are not limited thereto.

[0052] In the present specification, the cycloalkyl group is not particularly limited, but is preferably a cycloalkyl group having 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. Specifically, there are cyclopropyl, cyclobutyl, cyclopentyl, 3-methylcyclopentyl, 2,3-dimethylcyclopentyl, cyclohexyl, 3-methylcyclohexyl, 4-methylcyclohexyl, 2,3-dimethylcyclohexyl, 3,4,5-trimethylcyclohexyl, 4-tert-butylcyclohexyl, cycloheptyl, cyclooctyl, etc., but are not limited thereto.

[0053] In the present specification, the aryl group is not particularly limited, but is preferably an aryl group having 6 to 60 carbon atoms, and may be a monocyclic aryl group or a polycyclic aryl group. According to one embodiment, the carbon number of the aryl group is 6 to 30. According to one embodiment, the carbon number of the aryl group is 6 to 20. Regarding the aryl group, as a monocyclic aryl group, it may be phenyl, biphenyl, terphenyl, etc., but it is not limited thereto. As the polycyclic aryl group, it may be naphthyl, anthracenyl, phenanthrenyl, pyrenyl, peryl, yl, fluorenyl, etc., but are not limited to these.

[0054] In the present specification, the fluorenyl group may be substituted, and two substituents may be combined with each other to form a spiro structure. etc. However, the present invention is not limited thereto.

[0055] In the present specification, the heteroaryl group is a heteroaryl group containing one or more of O, N, Si and S as heteroatoms, and the number of carbon atoms is not particularly limited, but preferably the number of carbon atoms is 2 to 60. Examples of the heteroaryl group include thienyl, furyl, pyrrolyl, imidazolyl, thiazolyl, Azolyl, oxadiazolyl, triazolyl, pyridyl, bipyridyl, pyrimidyl, triazinyl, acridinyl, pyridazinyl, pyrazinyl, quinolyl, quinazolinyl, quinoxalinyl, phthalazinyl, pyridopyrimidinyl, pyridopyrazinyl, pyrazinopyrazinyl, isoquinolyl, indolyl, carbazolyl, benzo oxazolyl, benzimidazolyl, benzothiazolyl, benzocarbazolyl, benzothiophenyl, dibenzothiophenyl, benzofuranyl, phenanthroline, isothiophene oxazolyl, thiadiazolyl, phenothiazinyl and dibenzofuranyl, but are not limited thereto.

[0056] In this specification, the aryl group in aralkyl, aralkenyl, alkylaryl, and arylamine is the same as the examples of the above-mentioned aryl group. In this specification, the alkyl group in aralkyl, alkylaryl, and alkylamine is the same as the examples of the above-mentioned alkyl group. In this specification, the heteroaryl group in heteroarylamine can be applied to the above-mentioned description of the heteroaryl group. In this specification, the alkenyl group in aralkenyl is the same as the examples of the above-mentioned alkenyl group. In this specification, the arylene group is a divalent group, and the above-mentioned description of the aryl group can be applied. In this specification, the heteroarylene group is a divalent group, and the above-mentioned description of the heteroaryl group can be applied. In this specification, the hydrocarbon ring is not a monovalent group, but is formed by combining two substituents, and the above-mentioned description of the aryl group or the cycloalkyl group can be applied. In this specification, the heterocycle is not a monovalent group, but is formed by combining two substituents, and the above-mentioned description of the heteroaryl group can be applied.

[0057] The present invention provides an organic light-emitting device having the following structure:

[0058] anode;

[0059] a cathode disposed opposite to the anode;

[0060] A light-emitting layer including the second compound is provided between the anode and the cathode;

[0061] A hole transport region is provided between the anode and the light-emitting layer; and

[0062] An electron transport region is provided between the light-emitting layer and the cathode and contains the first compound.

[0063] Hereinafter, the present invention will be described in detail according to each configuration.

[0064] Anode and cathode

[0065] As the above-mentioned anode material, in order to enable holes to be smoothly injected into the organic layer, a material with a large work function is preferably used. Specific examples of the above-mentioned anode material include metals such as vanadium, chromium, copper, zinc, gold, or their alloys; metal oxides such as zinc oxide, indium oxide, indium tin oxide (ITO), indium zinc oxide (IZO); combinations of metals and oxides such as ZnO:Al or SnO2:Sb; conductive polymers such as poly(3-methylthiophene), poly[3,4-(ethylene-1,2-dioxy)thiophene] (PEDOT), polypyrrole, and polyaniline, but are not limited thereto.

[0066] In order to facilitate the injection of electrons into the organic layer, the cathode material is preferably a material with a small work function. Specific examples of the cathode material include metals such as magnesium, calcium, sodium, potassium, titanium, indium, yttrium, lithium, gadolinium, aluminum, silver, tin, and lead, or alloys thereof; multilayer structure materials such as LiF / Al or LiO2 / Al, etc., but are not limited thereto.

[0067] Hole transport region

[0068] The organic light-emitting device according to the present invention includes a hole transport region between the anode and the light-emitting layer. The hole transport region is a region that receives holes from the anode and transports the holes to the light-emitting layer, and it is suitable to contain a substance with a high mobility for holes. Preferably, the hole transport region includes a hole injection layer, a hole transport layer, and an electron blocking layer stacked in sequence from the anode.

[0069] (Hole Injection Layer)

[0070] The hole injection layer is a layer located on the anode and injecting holes from the anode, and contains a hole injection substance. As such a hole injection substance, it is preferably a compound that has the ability to transport holes, has the effect of injecting holes from the anode, has an excellent hole injection effect for the light-emitting layer or the light-emitting material, prevents the excitons generated in the light-emitting layer from migrating to the electron injection layer or the electron injection material, and has excellent film forming ability. In particular, it is suitable that the HOMO (highest occupied molecular orbital) of the hole injection substance is between the work function of the anode substance and the HOMO of the surrounding organic layer.

[0071] Specific examples of the hole injection material include metal porphyrin, oligothiophene, arylamine organic matter, hexanitrile hexaazatriphenylene organic matter, quinacridone organic matter, perylene organic matter, anthraquinone, polyaniline and polythiophene conductive polymers, but are not limited to these.

[0072] (Hole Transport Layer)

[0073] The hole transport layer is formed on the hole injection layer, and plays the role of receiving holes from the hole injection layer and transporting the holes to the light-emitting layer. The hole transport layer contains a hole transport substance, and as such a hole transport substance, a substance with a high mobility to holes that can receive holes from the anode or the hole injection layer and transfer them to the light-emitting layer is suitable.

[0074] Specific examples of the hole transport material include arylamine-based organic substances, conductive polymers, and block copolymers having both a conjugated portion and a non-conjugated portion, but the present invention is not limited thereto.

[0075] (Electron blocking layer)

[0076] The electron blocking layer is formed on the hole transport layer, preferably in contact with the light-emitting layer, and improves the efficiency of the organic light-emitting device by adjusting the hole mobility, preventing the excessive migration of electrons, and increasing the probability of the combination between holes and electrons. The electron blocking layer contains an electron blocking substance, and as such an electron blocking substance, a substance having a stable structure that prevents electrons from flowing out of the light-emitting layer is suitable.

[0077] Specific examples of the electron blocking material include arylamine-based organic substances, but the present invention is not limited thereto.

[0078] Luminescent layer

[0079] The organic light-emitting device according to the present invention comprises an anthracene compound substituted at positions 2, 9 and 10 as the second compound represented by the above Chemical Formula 2 as a host substance. In particular, the above second compound has a structure in which the same or different substituents are introduced at positions 9 and 10 and a substituent is introduced at position 2, and has excellent material stability compared to a compound in which no substituent is introduced at position 2, thereby contributing to improvement of life characteristics when used in an organic light-emitting device.

[0080] Preferably, in the above Chemical Formula 2, L2 and L3 may each independently be a single bond, or be selected from any one of the following groups:

[0081]

[0082] In the above groups,

[0083] Y1 is O, S, N (C 6-20 Aryl), C(C 1-4 Alkyl)2, or C(C 6-20 Aryl)2.

[0084] For example, Y1 is O, S, N(phenyl), C(methyl)2, or C(phenyl)2.

[0085] More preferably, L2 and L3 are each independently a single bond or a phenylene group.

[0086] Preferably, Ar3 and Ar4 are each independently C 6-20 Aryl, or C containing O or S 2-60 Heteroaryl.

[0087] More preferably, Ar3 and Ar4 are each independently phenyl, biphenyl, terphenyl, naphthyl, phenanthryl, dibenzofuranyl or dibenzothiophenyl.

[0088] Preferably, R is phenyl, biphenyl, terphenyl, naphthyl, phenanthryl, triphenylene, fluorenyl, carbazolyl, dibenzofuranyl or dibenzothiophenyl.

[0089] wherein R may be unsubstituted; or may be independently selected from deuterium, C 1-10 Alkyl, tri(C 1-4 alkyl)silyl and C 6-20 The aryl group is substituted with 1 to 5 substituents.

[0090] More preferably, R is any one selected from the following groups:

[0091]

[0092] In the above groups,

[0093] Q is hydrogen, C 1-10 Alkyl, Si(C 1-4 Alkyl)3, or C 6-20 Aryl,

[0094] Y2 is O, S, N (C 6-20 Aryl), C(C 1-4 Alkyl)2, or C(C 6-20 For example, Q is hydrogen, tert-butyl, Si(methyl)3, phenyl, or naphthyl,

[0095] Y2 is O, S, N(phenyl), C(methyl)2, or C(phenyl)2.

[0096] Preferably, the second compound is represented by the following chemical formula 2-1 or 2-2:

[0097] [Chemical formula 2-1]

[0098]

[0099] [Chemical formula 2-2]

[0100]

[0101] In the above chemical formulas 2-1 and 2-2,

[0102] L3, Ar4 and R are the same as defined in the above Chemical Formula 2.

[0103] Representative examples of the second compound are shown below:

[0104]

[0105]

[0106]

[0107]

[0108]

[0109]

[0110]

[0111]

[0112]

[0113]

[0114]

[0115]

[0116]

[0117]

[0118]

[0119]

[0120]

[0121] In this case, as an example, the second compound can be produced by a production method as shown in the following reaction formula 2. The production method can be further embodied in the production examples described below.

[0122] [Reaction 2]

[0123]

[0124] In the above reaction formula 2, T is a halogen, preferably bromine or chlorine, and the definitions of other substituents are the same as described above.

[0125] Specifically, the compound represented by the above chemical formula 2 is manufactured by introducing R substituents into the starting material through a Suzuki coupling reaction. Such a Suzuki coupling reaction is preferably carried out in the presence of a palladium catalyst and a base, and the reactive group for the Suzuki coupling reaction can be changed according to techniques known in the art. The above-mentioned manufacturing method can be more specifically described in the manufacturing example described later.

[0126] On the other hand, the light-emitting layer may further include a dopant material. Examples of the dopant material include aromatic amine derivatives, styrylamine compounds, boron complexes, fluoranthene compounds, metal complexes, and the like. Specifically, aromatic amine derivatives are aromatic fused ring derivatives having substituted or unsubstituted arylamino groups, such as pyrene, anthracene, The styrylamine compound is a compound in which at least one arylvinyl group is substituted on a substituted or unsubstituted arylamine, and is substituted or unsubstituted with one or more substituents selected from aryl, silyl, alkyl, cycloalkyl and arylamino. Specifically, there are styrylamine, styryldiamine, styryltriamine, styryltetramine, etc., but not limited thereto. In addition, as metal complexes, there are iridium complexes, platinum complexes, etc., but not limited thereto. Preferably, the above-mentioned light-emitting layer may contain an iridium complex as a dopant material.

[0127] The organic light-emitting device having the light-emitting layer including the host substance and the dopant substance can exhibit a maximum wavelength (λ) in the light-emitting spectrum at about 400 nm to about 500 nm. max ). Therefore, the above-mentioned organic light-emitting device is a blue light-emitting organic light-emitting device.

[0128] Electron transport region

[0129] The organic light emitting device according to the present invention includes an electron transport region provided between the light emitting layer and the cathode and transporting electrons from the cathode to the light emitting layer, wherein the electron transport region includes the first compound represented by the chemical formula 1.

[0130] The first compound has a structure in which an N-hexacyclic group as an electron-deficient substituent is combined in an electron-rich spiro[fluorene-9,9'-xanthene) core, thereby showing a low dipole moment value and amorphous properties. Therefore, when such a first compound is used in an organic light-emitting device, device damage caused by crystallization that may be caused by heat during device operation can be prevented, so the organic light-emitting device using the first compound has a low driving voltage and can show high efficiency.

[0131] The first compound is represented by any one of the following chemical formulas 1-1 to 1-4 according to the substitution position of the N-containing six-membered heterocyclic group:

[0132] [Chemical formula 1-1]

[0133]

[0134] [Chemical formula 1-2]

[0135]

[0136] [Chemical formula 1-3]

[0137]

[0138] [Chemical formula 1-4]

[0139]

[0140] In the above chemical formulas 1-1 to 1-4,

[0141] L1, X1 to X3, Ar1 and Ar2 are the same as defined in the above Chemical Formula 1.

[0142] Preferably, the first compound is represented by any one of the above Chemical Formulae 1-1 to 1-3.

[0143] Preferably, X1 to X3 are all N; or

[0144] X1 and X2 are N, and X3 is CH; or

[0145] X1 and X3 are N, and X2 is CH; or

[0146] X1 is N, X2 and X3 are CH; or

[0147] X3 is N, and X1 and X2 are CH.

[0148] Preferably, L1 is a single bond, or is selected from any one of the following groups:

[0149]

[0150] In the above groups,

[0151] X is O, S, N (C 6-20 Aryl), C(C 1-4 Alkyl)2, or C(C 6-20 Aryl)2.

[0152] For example, X is O, S, N(phenyl), C(methyl)2, or C(phenyl)2.

[0153] More preferably, L1 is a single bond, a phenylene group or a biphenyl diyl group.

[0154] Most preferably, L1 is a single bond, or any one selected from the following groups:

[0155]

[0156] Preferably, Ar1 and Ar2 are each independently phenyl, biphenyl, terphenyl, naphthyl, phenanthryl, triphenylene, fluorenyl, spirobifluorenyl, carbazolyl, dibenzofuranyl or dibenzothiophenyl.

[0157] Wherein, Ar1 and Ar2 may be unsubstituted or may be independently selected from deuterium, cyano, halogen, Si(C 1-4 Alkyl)3, C 1-10 Alkyl and C 6-20 The aryl group is substituted with 1 to 5 substituents.

[0158] More preferably, Ar1 and Ar2 are each independently selected from any one of the following groups:

[0159]

[0160] In the above groups,

[0161] Z is hydrogen, cyano, halogen, Si(C1-4 Alkyl)3, C 1-10 Alkyl, or C 6-20 Aryl,

[0162] X' is O, S, N (C 6-20 Aryl), C(C 1-4 Alkyl)2, or C(C 6-20 Aryl)2.

[0163] For example, Z is hydrogen, cyano, fluorine, Si(CH3)3, methyl, phenyl, naphthyl or phenanthryl, and X' is O, S, N(phenyl), N(naphthyl), C(methyl)2, or C(phenyl)2.

[0164] Representative examples of the above-mentioned first compound are shown below:

[0165]

[0166]

[0167]

[0168]

[0169]

[0170]

[0171]

[0172]

[0173]

[0174]

[0175]

[0176]

[0177]

[0178]

[0179] In this case, as an example, the first compound can be produced by a production method as shown in the following reaction formula 1. The production method can be further embodied in the production examples described below.

[0180] [Reaction 1]

[0181]

[0182] In the above reaction formula 1, T is independently a halogen, preferably bromine or chlorine, and the definitions of other substituents are the same as described above.

[0183] Specifically, the above steps 1-1 and 1-2 are steps of manufacturing a spiral [fluorene-9,9'-xanthene) core by a ring-forming reaction after reducing the starting material in the presence of a strong base, the above step 1-3 is a step of introducing a reactive group for Suzuki coupling reaction in the manufactured core, and the above step 1-4 is a step of manufacturing a compound represented by Chemical Formula 1 by introducing an N-hexacyclic group in the above core by Suzuki coupling reaction. Such a Suzuki coupling reaction is preferably carried out in the presence of a palladium catalyst and a base, and the reactive group for the Suzuki coupling reaction can be changed according to the technology known in the art. The above-mentioned manufacturing method can be more specific in the manufacturing example described later.

[0184] On the other hand, the electron transport region may be composed of a hole blocking layer and an electron transport layer stacked in sequence from the light-emitting layer; a hole blocking layer and an electron injection and transport layer; or a hole blocking layer, an electron transport layer and an electron injection layer. Preferably, the hole blocking layer is located at a position in contact with the light-emitting layer, and the first compound is contained in the hole blocking layer or the electron transport layer. More preferably, the first compound is contained in the electron transport layer.

[0185] Next, each organic layer will be described in detail.

[0186] (Hole Blocking Layer)

[0187] The hole blocking layer is formed on the light-emitting layer. Specifically, the hole blocking layer is provided in contact with the light-emitting layer, and improves the probability of hole-electron combination by preventing excessive migration of holes, thereby improving the efficiency of the organic light-emitting device. The hole blocking layer contains a hole blocking substance. As such a hole blocking substance, a substance having a stable structure that prevents holes from flowing out of the light-emitting layer is suitable.

[0188] Preferably, as the hole blocking material, the first compound represented by the above chemical formula 1 is used. Alternatively, as the hole blocking material, an azine derivative including triazine, a triazole derivative, Compounds into which an electron-withdrawing group is introduced include, but are not limited to, oxadiazole derivatives, phenanthroline derivatives, phosphine oxide derivatives, and the like.

[0189] (Electron Transport Layer)

[0190] The electron transport layer is formed between the light-emitting layer and the cathode, preferably between the hole blocking layer and the electron injection layer described later, and plays the role of receiving electrons from the electron injection layer and transferring the electrons to the light-emitting layer. The electron transport layer contains an electron transport substance, which is a substance that can well receive electrons from the cathode and transfer them to the light-emitting layer, and a substance with a large electron mobility is suitable.

[0191] Preferably, as the electron transport material, the first compound represented by the above chemical formula 1 is used. Alternatively, as the electron transport material, pyridine derivatives, pyrimidine derivatives, triazole derivatives, triazine derivatives, Al complexes of 8-hydroxyquinoline, complexes containing Alq3, organic free radical compounds, hydroxyflavone-metal complexes, etc. can be used, but are not limited thereto.

[0192] In addition, the electron transport layer may include the electron transport material and a metal coordination compound. Examples of the metal coordination compound include 8-hydroxyquinoline lithium, bis(8-hydroxyquinoline) zinc, bis(8-hydroxyquinoline) copper, bis(8-hydroxyquinoline) manganese, tris(8-hydroxyquinoline) aluminum, tris(2-methyl-8-hydroxyquinoline) aluminum, tris(8-hydroxyquinoline) gallium, bis(10-hydroxybenzo[h]quinoline) beryllium, bis(10-hydroxybenzo[h]quinoline) zinc, bis(2-methyl-8-quinoline) gallium chloride, bis(2-methyl-8-quinoline)(o-cresol) gallium, bis(2-methyl-8-quinoline)(1-naphthol) aluminum, bis(2-methyl-8-quinoline)(2-naphthol) gallium, etc., but are not limited thereto.

[0193] (Electron Injection Layer)

[0194] The electron injection layer is located between the electron transport layer and the cathode, and plays the role of injecting electrons from the cathode. The electron injection layer contains an electron injection substance, and as such an electron injection substance, the following substances are suitable: substances having the ability to transport electrons, having an excellent electron injection effect for the light-emitting layer or the light-emitting material, and having excellent thin film forming ability.

[0195] Specific examples of the electron injecting material include LiF, NaCl, CsF, Li2O, BaO, fluorenone, anthraquinone dimethane, diphenoquinone, thiopyran dioxide, Azoles, Examples include, but are not limited to, diazole, triazole, imidazole, perylenetetracarboxylic acid, fluorenylene methane, anthrone, and derivatives thereof, metal coordination compounds, and nitrogen-containing five-membered ring derivatives.

[0196] Organic light-emitting devices

[0197] The structure of the organic light emitting device according to the present invention is shown in Figure 1and Figure 2 .

[0198] Figure 1 The figure shows an example of an organic light-emitting device composed of a substrate 10, an anode 20, a hole transport region 30, a light-emitting layer 40, an electron transport region 50, and a cathode 60. In the above structure, the first compound is contained in the electron transport region 50, and the second compound is contained in the light-emitting layer 40.

[0199] Figure 2 The figure shows an example of an organic light-emitting device composed of a substrate 10, an anode 20, a hole transport region 30, a light-emitting layer 40, an electron transport region 50, and a cathode 60. The hole transport region 30 includes a hole injection layer 31, a hole transport layer 33, and an electron blocking layer 35 stacked in order from the anode 20, and the electron transport region 50 includes a hole blocking layer 51, an electron transport layer 53, and an electron injection layer 55 stacked in order from the light-emitting layer 40. In the above structure, the first compound may be contained in the hole blocking layer 51 or the electron transport layer 53, and the second compound may be contained in the light-emitting layer 40.

[0200] The organic light-emitting device according to the present invention can be manufactured by stacking the above-mentioned structures in sequence. In this case, it can be manufactured as follows: a PVD (physical vapor deposition) method such as sputtering or electron beam evaporation is used to vapor-deposit a metal or a conductive metal oxide or an alloy thereof on a substrate to form an anode, and after forming the above-mentioned layers on the anode, a substance that can be used as a cathode is vapor-deposited on the layer to manufacture. In addition to this method, an organic light-emitting device can also be manufactured by vapor-depositing a cathode substance, an organic layer, and an anode substance on a substrate in sequence. In addition, not only a vacuum evaporation method but also a solution coating method can be used to form a main body and a dopant into a light-emitting layer. Here, the so-called solution coating method refers to spin coating, dip coating, blade coating, inkjet printing, screen printing, spraying, roller coating, etc., but is not limited to this.

[0201] In addition to these methods, an organic light-emitting device can also be manufactured by sequentially depositing a cathode material, an organic layer, and an anode material on a substrate (WO 2003 / 012890). However, the manufacturing method is not limited to this.

[0202] On the other hand, the organic light emitting device according to the present invention may be a top emission type, a bottom emission type, or a bi-directional emission type according to the materials used.

[0203] The production of the organic light-emitting device is specifically described in the following examples. However, the following examples are used to illustrate the present invention, and the scope of the present invention is not limited thereto.

[0204] Preparation Example 1: Preparation of Compound 1-1

[0205]

[0206] In a 500 ml round-bottom flask under a nitrogen atmosphere, compound A (12.13 g, 26.49 mmol) and (4-(4,6-diphenyl-1,3,5-triazine-2-yl)phenyl)boric acid (8.50 g, 24.08 mmol) were completely dissolved in 200 ml of tetrahydrofuran, and then a 2M potassium carbonate aqueous solution (100 ml) was added. After adding tetrakis(triphenylphosphine)palladium (0.83 g, 0.72 mmol), the mixture was heated and stirred for 3 hours. The temperature was lowered to room temperature, the water layer was removed, dried over anhydrous magnesium sulfate, and then concentrated under reduced pressure, and recrystallized from 280 ml of ethyl acetate to produce compound 1-1 (11.16 g, 72%).

[0207] MS[M+H] + =640

[0208] Preparation Example 2: Preparation of Compound 1-2

[0209]

[0210] In a 500 ml round-bottom flask under a nitrogen atmosphere, compound B (10.70 g, 23.37 mmol) and 2-([1,1'-biphenyl]-4-yl)-4-chloro-6-phenyl-1,3,5-triazine (7.5 g, 21.25 mmol) were completely dissolved in 220 ml of tetrahydrofuran, and then a 2M potassium carbonate aqueous solution (110 ml) was added. After adding tetrakis(triphenylphosphine)palladium (0.74 g, 0.64 mmol), the mixture was heated and stirred for 4 hours. The temperature was lowered to room temperature, the water layer was removed, dried over anhydrous magnesium sulfate, and then concentrated under reduced pressure, and recrystallized from 240 ml of ethyl acetate to produce compound 1-2 (8.46 g, 62%).

[0211] MS[M+H] + =640

[0212] Preparation Example 3: Preparation of Compound 1-3

[0213]

[0214] In a 500 ml round-bottom flask under a nitrogen atmosphere, compound C (7.49 g, 16.36 mmol) and 2-(4-bromophenyl)-4-(naphthalene-1-yl)-6-phenyl-1,3,5-triazine (6.50 g, 14.87 mmol) were completely dissolved in 200 ml of tetrahydrofuran, and then a 2M potassium carbonate aqueous solution (100 ml) was added. After adding tetrakis(triphenylphosphine)palladium (0.52 g, 0.45 mmol), the mixture was heated and stirred for 3 hours. The temperature was lowered to room temperature, the water layer was removed, dried over anhydrous magnesium sulfate, and then concentrated under reduced pressure, and recrystallized from 180 ml of tetrahydrofuran to produce compound 1-3 (5.89 g, 62%).

[0215] MS[M+H] + =690

[0216] Preparation Example 4: Preparation of Compound 2-1

[0217]

[0218] Under nitrogen atmosphere, in a 500 ml round-bottom flask, compound 2-bromo-10-(naphthalene-1-yl)-9-phenylanthracene (15.50 g, 33.84 mmol) and naphthalene-2-ylboric acid (6.40 g, 37.23 mmol) were completely dissolved in 260 ml of tetrahydrofuran, and then 2M potassium carbonate aqueous solution (130 ml) was added, and tetrakis(triphenylphosphine)palladium (1.17 g, 1.02 mmol) was added, and then heated and stirred for 4 hours. The temperature was lowered to room temperature, the water layer was removed, dried over anhydrous magnesium sulfate, and then concentrated under reduced pressure, and recrystallized from 250 ml of ethyl acetate to produce compound 2-1 (8.64 g, 50%).

[0219] MS[M+H] + =507

[0220] Preparation Example 5: Preparation of Compound 2-2

[0221]

[0222] In a 500 ml round-bottom flask under a nitrogen atmosphere, the compound 2-bromo-10-(phenanthrene-9-yl)-9-phenylanthracene (9.50 g, 18.70 mmol) and dibenzo[b,d]furan-2-ylboronic acid (4.36 g, 20.57 mmol) were completely dissolved in 240 ml of tetrahydrofuran, and then a 2M potassium carbonate aqueous solution (120 ml) was added. After adding tetrakis(triphenylphosphine)palladium (0.65 g, 0.56 mmol), the mixture was heated and stirred for 4 hours. The temperature was lowered to room temperature, the water layer was removed, dried over anhydrous magnesium sulfate, and then concentrated under reduced pressure. The mixture was recrystallized with 240 ml of ethyl acetate to produce compound 2-2 (6.44 g, 58%).

[0223] MS[M+H] + =597

[0224] Preparation Example 6: Preparation of Compound 2-3

[0225]

[0226] In a 500 ml round-bottom flask under a nitrogen atmosphere, the compound 3-(3-bromo-10-phenylanthracene-9-yl)dibenzo[b,d]thiophene (7.50 g, 14.59 mmol) and [1,1'-biphenyl]-3-ylboronic acid (3.18 g, 16.05 mmol) were completely dissolved in 180 ml of tetrahydrofuran, and then a 2M potassium carbonate aqueous solution (90 ml) was added. After adding tetrakis(triphenylphosphine)palladium (0.51 g, 0.44 mmol), the mixture was heated and stirred for 4 hours. The temperature was lowered to room temperature, the water layer was removed, dried over anhydrous magnesium sulfate, and then concentrated under reduced pressure, and recrystallized from 270 ml of ethyl acetate to produce compound 2-3 (5.11 g, 89%).

[0227] MS[M+H] + =589

[0228] Example 1

[0229] ITO (indium tin oxide) is used The glass substrate coated with a film of a thickness of 10000 mm was placed in distilled water dissolved with a detergent and washed with ultrasonic waves. At this time, the detergent used a product of Fischer Co., and the distilled water used distilled water filtered twice by a filter manufactured by Millipore Co. After ITO was washed for 30 minutes, ultrasonic washing was repeated twice with distilled water for 10 minutes. After the distilled water washing was completed, ultrasonic washing was carried out with a solvent of isopropanol, acetone, and methanol and dried, and then transported to a plasma cleaning machine. In addition, after the above-mentioned substrate was cleaned for 5 minutes using oxygen plasma, the substrate was transported to a vacuum evaporator.

[0230] On the ITO transparent electrode prepared in this way, the following compound HI-1 and the following compound HI-2 were mixed in a ratio of 98:2 (molar ratio). A hole injection layer is formed by thermal vacuum deposition to a thickness of .

[0231] On the hole injection layer, the following compound HT-1 was placed as a hole transporting substance. The hole transport layer is formed by vacuum deposition.

[0232] Next, on the hole transport layer, a film with a thickness of The following compound EB-1 was vacuum-deposited to form an electron blocking layer.

[0233] Next, on the electron blocking layer, a film with a thickness of The compound 2-1 (host) prepared in the above-mentioned Preparation Example 4 and the following compound BD-1 (dopant) were vacuum deposited at a weight ratio of 40:1 to form a light-emitting layer.

[0234] On the above-mentioned light-emitting layer, the film thickness is The following compound HB-1 was vacuum deposited to form a hole blocking layer.

[0235] Next, the compound 1-1 prepared in the above-mentioned Preparation Example 1 and the following compound LiQ (Lithium Quinolate, 8-hydroxyquinoline lithium) were vacuum-deposited at a weight ratio of 1:1 on the above-mentioned hole blocking layer, thereby forming a An electron transport layer is formed with a thickness of

[0236] On the electron transport layer, lithium fluoride (LiF) is sequentially The thickness of the aluminum The electron injection layer and the cathode are formed by evaporation to a thickness of , respectively.

[0237] In the above process, the evaporation rate of organic matter is maintained / second, the cathode lithium fluoride maintains The evaporation speed is 2.5 seconds, and the aluminum maintains The evaporation speed is 2×10 / s. During evaporation, the vacuum degree is maintained at 2×10 -7 ~5×10 -6 A support is provided to produce an organic light-emitting device.

[0238] The compounds used in the above Example 1 are shown below.

[0239]

[0240] Examples 2 to 9 and Comparative Examples 1 to 10

[0241] In Example 1, an organic light-emitting device was manufactured by the same method as in Example 1, except that the compounds listed in Table 1 below were used instead of the host compound 2-1 and the compound 1-1 of the electron transport layer. The compounds used in the above examples and comparative examples are shown below.

[0242]

[0243] The organic light-emitting devices manufactured in the above examples and comparative examples were subjected to a 20 mA / cm 2 When the current of the organic light emitting device is 20mA / cm 2 The driving voltage, luminous efficiency and color coordinates were measured at a current density of 20 mA / cm 2 The time required for the luminance to decrease to 95% relative to the initial luminance (T95) was measured at a current density of . The results are shown in the following Table 1. In this case, T95 refers to the time required for the luminance to decrease from the initial luminance (1600 nits) to 95%.

[0244] [Table 1]

[0245]

[0246] As shown in Table 1 above, the organic light-emitting device of the embodiment using the compound represented by Chemical Formula 1 as the electron transport layer material and the compound represented by Chemical Formula 2 as the main material of the light-emitting layer at the same time shows excellent characteristics in terms of driving voltage, luminous efficiency and lifespan compared with the organic light-emitting device of the comparative example using only one of the compounds represented by Chemical Formulas 1 and 2, or neither of them.

[0247] Specifically, from Comparative Examples 1 to 3 and Comparative Examples 8 to 10, it can be seen that the compound represented by the above chemical formula 1 has excellent electron injection characteristics and electron migration characteristics to the light-emitting layer compared with ET-1 in which a triazine group is connected to 9,9-diphenyl-9H-fluorene and ET-2 in which a triazine group is connected to triphenylene, thereby contributing to the improvement of device efficiency. Moreover, from Comparative Examples 4 to 7, Comparative Example 9 and Comparative Example 10, it can be seen that the compound represented by the above chemical formula 2 has excellent material stability compared with Comparative Example compounds BH-1 and BH-2 that do not have a substituent at the 2nd position of anthracene, thereby contributing to the long life characteristics of the device.

[0248] In addition, unlike the organic light-emitting devices of Comparative Examples 9 and 10, in which the efficiency and life characteristics were not improved at the same time even when ET-2 and BH-2 and ET-1 and BH-1 were combined with each other, it was confirmed that the organic light-emitting device according to the embodiment of the present invention using the compound represented by the above Chemical Formula 1 and the compound represented by the above Chemical Formula 2 simultaneously improved the efficiency and life characteristics. In this regard, considering that the luminous efficiency and life characteristics of the organic light-emitting device are generally in a trade-off relationship with each other, it can be seen that the organic light-emitting device using the combination of the compounds of the present invention shows significantly improved device characteristics compared with the comparative example device.

[0249] [Explanation of symbols]

[0250] 10: substrate 20: anode

[0251] 30: Hole transport region 31: Hole injection layer

[0252] 33: hole transport layer 35: electron blocking layer

[0253] 40: Light-emitting layer 50: Electron transport region

[0254] 51: hole blocking layer 53: electron transport layer

[0255] 55: electron injection layer 60: cathode.

Claims

1. An organic light-emitting device, wherein: include: anode; a cathode disposed opposite to the anode; A light-emitting layer is provided between the anode and the cathode; having a hole transport region between the anode and the light-emitting layer; as well as An electron transport region is provided between the light emitting layer and the cathode, The hole transport region includes a hole injection layer, a hole transport layer and an electron blocking layer. The electron transport region includes a hole blocking layer and an electron transport layer; a hole blocking layer and an electron injection and transport layer; or a hole blocking layer, an electron transport layer and an electron injection layer, The hole blocking layer or the electron transport layer includes a first compound represented by the following Chemical Formula 1, and The light-emitting layer includes a second compound represented by the following Chemical Formula 2: Chemical formula 1 In the chemical formula 1, X1 to X3 are N, L1 is a single bond or a phenylene group, and Ar1 and Ar2 are each independently phenyl, biphenyl, terphenyl, naphthyl, phenanthryl or triphenylene, wherein Ar1 and Ar2 are unsubstituted or are each independently selected from deuterium, cyano, halogen, Si(C 1-4 Alkyl)3, C 1-10 1 to 5 substituents are substituted in the alkyl group and the phenyl group, Chemical formula 2 In the chemical formula 2, L2 and L3 are each a single bond, Ar3 and Ar4 are each independently phenyl, biphenyl, terphenyl, naphthyl, phenanthryl, dibenzofuranyl or dibenzothiophenyl, and R is phenyl, biphenyl, terphenyl, naphthyl, phenanthryl, triphenylene, fluorenyl, carbazolyl, dibenzofuranyl or dibenzothiophenyl, wherein R is unsubstituted; or is independently selected from deuterium, C 1-10 Alkyl, tri(C 1-4 The phenyl group and the silyl group may be substituted with 1 to 5 substituents.

2. The organic light emitting device according to claim 1, wherein: The first compound is represented by any one of the following chemical formulas 1-1 to 1-3: Chemical formula 1-1 Chemical formula 1-2 Chemical formula 1-3 In the chemical formulas 1-1 to 1-3, L1, X1 to X3, Ar1 and Ar2 are the same as defined in claim 1.

3. The organic light emitting device according to claim 1, wherein: L1 is a single bond or 4. The organic light emitting device according to claim 1, wherein: L1 is a single bond or 5. The organic light emitting device according to claim 1, wherein: L1 is a single bond or 6. The organic light emitting device according to claim 1, wherein: Ar1 and Ar2 are each independently selected from any one of the following groups: In the group, Z is hydrogen, cyano, halogen, Si(C 1-4 Alkyl)3, C 1-10 Alkyl or phenyl.

7. The organic light emitting device according to claim 1, wherein: The first compound is any one selected from the following compounds:

8. The organic light emitting device according to claim 1, wherein: R is any one selected from the following groups: In the group, Q is hydrogen, C 1-10 Alkyl, Si(C 1-4 alkyl)3, or phenyl, and Y2 is O, S, N (phenyl), C (C 1-4 alkyl)2, or C(phenyl)2.

9. The organic light emitting device according to claim 1, wherein: The second compound is represented by the following chemical formula 2-1 or 2-2: Chemical formula 2-1 Chemical formula 2-2 In the chemical formulas 2-1 and 2-2, L3, Ar4 and R are the same as defined in claim 1.

10. The organic light emitting device according to claim 1, wherein: The second compound is any one selected from the following compounds:

11. The organic light emitting device according to claim 1, wherein: The hole blocking layer is positioned in contact with the light emitting layer.

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