Novel compounds and organic light-emitting elements comprising the same

Abstract

The present application provides a compound represented by the following Chemical Formula 1 and an organic light emitting element including the same: <Chemical Formula 1>

Description

TECHNICAL FIELD

[0001] The present application relates to a novel compound and an organic light emitting element comprising the same. BACKGROUND

[0002] Recently, a low-voltage driven self-emitting organic light emitting element has advantages over a liquid crystal display (LCD) which is the mainstream of flat panel displays, such as a wide viewing angle, a high contrast ratio, no need for a backlight, light weight and thinness, low power consumption, a wide color reproduction range, and the like, and thus is attracting attention as a next-generation display element.

[0003] Materials used in the organic light emitting element as an organic layer can be broadly classified into a light emitting layer material, a hole injecting material, a hole transporting material, an electron transporting material, an electron injecting material, and the like, according to their functions.

[0004] In addition, the light emitting material can be classified into a high molecule and a single molecule according to a molecular weight, and can be classified into a fluorescent material derived from a singlet excited state of an electron, a phosphorescent material derived from a triplet excited state of an electron, and a delayed fluorescent material derived from a movement of an electron from a triplet excited state to a singlet excited state according to a light emitting mechanism, and can be classified into a blue, a green, a yellow, and a red light emitting material according to a light emitting color.

[0005] In addition, in order to improve color purity and light emitting efficiency based on energy transfer, a host / dopant type material can be used as a light emitting material. The principle thereof is that by mixing a small amount of a light emitting material having a smaller energy band gap than a host, i.e., a dopant, into a light emitting layer, an exciton generated in the host is transferred to the dopant and emits light. By the principle as described above, light of a desired wavelength can be obtained according to the types of the host and the dopant.

[0006] So far, as a material suitable for the organic light emitting element, a variety of compounds have been known, but since the organic light emitting element using the material known so far has problems of a high driving voltage, a low efficiency, and a short lifespan, there is still a need to develop a novel material. Therefore, efforts have been made to develop an organic light emitting element capable of low voltage driving, having high brightness, and having a long lifespan, using a material having excellent properties. SUMMARY

[0007] An object of the present application is to provide a novel compound and an organic light emitting element which have a higher lowest unoccupied molecular orbital (LUMO) while forming a deeper highest occupied molecular orbital (HOMO), and T1, so that electron interception and exciton movement interception can be easily achieved and charge balance in a light emitting layer is excellent.

[0008] Further, an object of the present application is to provide a novel compound and an organic light emitting element which have a faster Hall mobility, and because π-conjugation is improved, excellent molecular arrangement can be ensured when forming a thin film, so that low driving voltage and high efficiency can be achieved, and long service life effects can be achieved by suppressing a deterioration phenomenon.

[0009] Further, an object of the present application is to provide a novel compound and an organic light emitting element which have a higher glass transition temperature (Tg), so that re-crystallization of a thin film can be prevented and driving stability is thereby improved.

[0010] Next, the problems and additional problems as described above will be described in detail.

[0011] As a means to solve the above problems,

[0012] One embodiment of the present application provides a compound represented by the following Chemical Formula 1.

[0013] <Chemical Formula 1>

[0014]

[0015] In the above Chemical Formula 1,

[0016] Ar1 is a phenyl group or an unsubstituted C7 to C30 fused aryl group, but does not include a fluorene group;

[0017] Ar2 is a substituted or unsubstituted C6 to C50 aryl group, or a substituted or unsubstituted C2 to C50 heteroaryl group, but does not include a fluorene group or a carbazole group;

[0018] L1 and L2 are each independently a direct bond, a substituted or unsubstituted C6 to C50 arylene group, or a substituted or unsubstituted C2 to C50 heteroarylene group;

[0019] R, R', R1 to R4 are each independently hydrogen, deuterium, a halogen, a nitro group, a nitrile group, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C2 to C30 alkenyl group, a substituted or unsubstituted C1 to C30 alkoxy group, a substituted or unsubstituted C1 to C30 thiol group, a substituted or unsubstituted C3 to C30 silyl group, a substituted or unsubstituted C6 to C50 aryl group, or a substituted or unsubstituted C2 to C50 heteroaryl group;

[0020] l is an integer of 0 to 4;

[0021] m is an integer of 0 to 2; and,

[0022] n is an integer of 0 to 4.

[0023] Further, as an embodiment of the present application, there is provided an organic light emitting element comprising:

[0024] a first electrode;

[0025] an organic layer on the first electrode; and,

[0026] a second electrode on the organic layer;

[0027] the organic layer comprises the compound as described above.

[0028] wherein the organic layer can be one or more layers selected from the group consisting of a hole injection layer, a hole transport layer, and a light emitting auxiliary layer, and in particular, can be a light emitting auxiliary layer between the hole transport layer and the light emitting layer.

[0029] The compound according to the present application has a structure in which an amine group is bonded to position 1, 3, or 4 of a fluorene group through a linker comprising an ortho-aryl group, in particular, 1,2-phenylene, and thus has a deep highest occupied molecular orbital (HOMO) and a high lowest unoccupied molecular orbital (LUMO) and T1, so that electron trapping and exciton migration trapping can be easily achieved and charge balance in a light emitting layer is excellent.

[0030] In particular, the compound according to the present application can increase π-conjugation through the extension of the linker comprising an ortho-aryl group, in particular, 1,2-phenylene, and a terminal aryl group (Ar2 in Chemical Formula 1), and thus has a fast hole mobility, and can secure excellent molecular arrangement when a thin film is formed, and thus has a low driving voltage and achieves high efficiency, and can achieve a long service life effect by suppressing a decay phenomenon.

[0031] Further, a very deep highest occupied molecular orbital (HOMO) and a high lowest unoccupied molecular orbital (LUMO) and T1 are maintained by including an unextended aryl structure (Ar1 in Chemical Formula 1) on one side of the amine group, and thus exciton confinement effects in a light emitting layer can be maximized, and thus the efficiency of an organic light emitting element can be further improved.

[0032] Further, the compound according to the present application can have a high glass transition temperature (Tg) through the extension of the linker between the fluorene group and the amine group, that is, the ortho-aryl group, and thus prevents recrystallization of a thin film, and thus an organic light emitting element having excellent driving stability can be achieved.

[0033] Next, the effects described above and additional effects will be described in detail. BRIEF DESCRIPTION OF DRAWINGS

[0034] FIG. 1 is a schematic cross-sectional view illustrating a configuration of an organic light emitting element according to an embodiment of the present application.

[0035] SYMBOL DESCRIPTION

[0036] 100: substrate

[0037] 200: hole injection layer

[0038] 300: hole transport layer

[0039] 400: light emitting layer

[0040] 500: electron transport layer

[0041] 600: electron injection layer

[0042] 1000: first electrode (anode)

[0043] 2000: second electrode (cathode) DETAILED DESCRIPTION

[0044] Before a detailed description of the present application is made, it is to be understood that the terminology used in the specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the present application which is defined by the appended claims. Unless otherwise defined, all technical and scientific terms used in the specification have the same meaning as commonly understood by one of ordinary skill in the art.

[0045] Throughout this specification and claims, unless otherwise indicated, the terms "comprise", "comprises", "comprising" are to be construed as meaning "including, but not limited to".

[0046] Throughout this specification and claims, the term "aryl group" means a C6-C50 aromatic hydrocarbon ring group such as a C6-C50 aromatic hydrocarbon ring group including a phenyl group, a benzyl group, a naphthyl group, a biphenyl group, a terphenyl group, a fluorenyl group, a phenanthryl group, a triphenylenyl group, a phenylene group, a fluoranthenyl group, a benzofluoranthenyl group, a benzophenanthryl group, an anthryl group, a stilbenyl group, and a pyrenyl group.

[0047] ​​Further, the term "heteroaryl group" can mean a C2-C50 aromatic ring including at least one hetero element such as pyrrolyl, pyrazinyl, pyridyl, indolyl, isoindolyl, furanyl, benzofuranyl, isobenzofuranyl, dibenzofuranyl, benzothienyl, dibenzothienyl, quinolyl, isoquinolyl, quinoxalyl, carbazolyl, phenanthridyl, acridyl, phenanthrolinyl, thienyl, and pyridine, pyrazine, pyrimidine, pyridazine, triazine, indole, quinoline, acridine, pyrrolidine, dioxane, piperidine, morpholine, piperazine, carbazole, furan, thiophene, oxazole, oxadiazole, benzoxazole, thiazole, thiadiazole, benzothiazole, benzotriazole, imidazole, benzimidazole, pyran, dibenzofuran, and the like.

[0048] Further, Ar in the chemical formula x (wherein x is an integer) means a substituted or unsubstituted C6-C50 aryl group, or a substituted or unsubstituted C2-C50 heteroaryl group, unless explicitly defined otherwise, L x (wherein x is an integer) means a direct bond, a substituted or unsubstituted C6-C50 arylene group, or a substituted or unsubstituted C2-C50 heteroarylene group, unless explicitly defined otherwise, R x (wherein x is an integer) means hydrogen, deuterium, halogen, nitro, nitrile, a substituted or unsubstituted C1-C30 alkyl group, a substituted or unsubstituted C2-C30 alkenyl group, a substituted or unsubstituted C1-C30 alkoxy group, a substituted or unsubstituted C1-C30 thiol group, a substituted or unsubstituted C6-C50 aryl group, or a substituted or unsubstituted C2-C50 heteroaryl group, unless explicitly defined otherwise.

[0049] Throughout the present specification and claims, the term "substituted or unsubstituted" can mean substituted or unsubstituted with any one or more selected from the group consisting of deuterium, halogen, amino, cyano, nitrile, nitro, nitroso, sulfonamide, isothiocyanate, thiocyanate, carboxyl, or a C1-C30 alkyl group, a C1-C30 alkylsulfinyl group, a C1-C30 alkylsulfonyl group, a C1-C30 alkylsulfanyl group, a C1-C12 fluoroalkyl group, a C2-C30 alkenyl group, a C1-C30 alkoxy group, a C1-C12 N-alkylamino group, a C2-C20 N,N-dialkylamino group, a substituted or unsubstituted C1-C30 thiol group, a C1-C6 N-alkylsulfonamide group, a C2-C12 N,N-dialkylsulfonamide group, a C3-C30 silyl group, a C3-C20 cycloalkyl group, a C3-C20 heterocycloalkyl group, a C6-C50 aryl group, and a C2-C50 heteroaryl group. Further, throughout the present specification, the same symbol can have the same meaning, unless explicitly stated otherwise.

[0050] Further, unless otherwise explicitly described, embodiments of the present application can be combined with other certain embodiments. Next, embodiments of the present application and effects thereof will be described.

[0051] Next, the present application will be described in detail.

[0052] The compound according to the present application is represented by the following Chemical Formula 1.

[0053] <Chemical Formula 1>

[0054]

[0055] In the above Chemical Formula 1,

[0056] Ar1 is a phenyl group or an unsubstituted C7 to C30 fused aryl group, but does not include a fluorene group;

[0057] Ar2 is a substituted or unsubstituted C6 to C50 aryl group, or a substituted or unsubstituted C2 to C50 heteroaryl group, but does not include a fluorene group or a carbazole group;

[0058] L1 and L2 are each independently a direct bond, a substituted or unsubstituted C6 to C50 arylene group, or a substituted or unsubstituted C2 to C50 heteroarylene group;

[0059] R, R', R1 to R4 are each independently hydrogen, deuterium, a halogen, a nitro group, a nitrile group, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C2 to C30 alkenyl group, a substituted or unsubstituted C1 to C30 alkoxy group, a substituted or unsubstituted C1 to C30 thiol group, a substituted or unsubstituted C3 to C30 silyl group, a substituted or unsubstituted C6 to C50 aryl group, or a substituted or unsubstituted C2 to C50 heteroaryl group;

[0060] l is an integer of 0 to 4;

[0061] m is an integer of 0 to 2; and

[0062] n is an integer of 0 to 4.

[0063] At this time, the above R1 can preferably be hydrogen, deuterium, a halogen, a nitro group, a nitrile group, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C2 to C30 alkenyl group, a substituted or unsubstituted C1 to C30 alkoxy group, a substituted or unsubstituted C1 to C30 thiol group, a substituted or unsubstituted C3 to C30 silyl group, or a substituted or unsubstituted C6 to C50 aryl group.

[0064] wherein the above R and R' can each independently be a substituted or unsubstituted C1 to C6 alkyl, a substituted or unsubstituted C6 to C30 aryl, or a substituted or unsubstituted C2 to C30 heteroaryl.

[0065] In the above, the substituent at the time of substitution can be one of the substituents as described above, and specifically can be a methyl group or a phenyl group, but is not limited thereto.

[0066] As described above, the compound represented by Chemical Formula 1 according to the present application has a structure in which an amine group is bonded to the 1st, 3rd or 4th position of a fluorene group through a linker including an ortho aryl group (specifically, a 1,2-phenylene group), and thus can achieve a deeper highest occupied molecular orbital (HOMO) that is beneficial to a light-emitting auxiliary layer and a higher lowest unoccupied molecular orbital that is beneficial to electron interception. In particular, in the case where R and R' are a methyl group or a phenyl group, since the volume characteristics of the fluorene group can be minimized to suppress a decrease in Hall mobility, the driving voltage can be effectively improved, and since thin film deposition can be performed at a lower temperature, the thermal stability is very excellent.

[0067] Specifically, the above Chemical Formula 1 can be represented by the following Chemical Formula 2:

[0068] <Chemical Formula 2>

[0069]

[0070] In the above Chemical Formula 2,

[0071] The definitions of Ar1, Ar2, L1, L2, R, R', R1 to R4, l, m and n are the same as those in the above Chemical Formula 1,

[0072] L2 is connected to any one of the * positions.

[0073] As described above, the compound represented by Chemical Formula 2 according to the present application has a structure in which a linker (L2) is bonded to the 3rd or 4th position of a fluorene group, and thus not only can a thin film be formed at a lower deposition temperature, but also a higher glass transition temperature (Tg) can be achieved. In addition, the above compound represented by Chemical Formula 2 can form a deeper highest occupied molecular orbital (HOMO) while having a higher lowest unoccupied molecular orbital (LUMO) by minimizing the warping of the molecule, and thus can easily adjust the electron balance, and is advantageous in improving the efficiency and lifespan of a light-emitting element including the corresponding compound.

[0074] In addition, the above Chemical Formula 1 can be represented by the following Chemical Formula 3:

[0075] <Chemical Formula 3>

[0076]

[0077] In the above Chemical Formula 3,

[0078] Ar1, Ar2, L2, R1 to R4, l, m, and n are defined the same as in Chemical Formula 1 above,

[0079] R and R' are each independently a substituted or unsubstituted C1 to C6 alkyl, a substituted or unsubstituted C6 to C30 aryl, or a substituted or unsubstituted C2 to C30 heteroaryl,

[0080] L2 is attached to any one of the * positions.

[0081] As described above, the compound represented by Chemical Formula 3 according to the present application has a structure in which L2 is attached to any one of the * positions (3rd or 4th position in fluorene) and L1 is directly bonded, compared to the compound represented by Chemical Formula 2, and thus it is possible to introduce an amine group into fluorene by means of an ortho-phenylene group, thereby forming a deeper highest occupied molecular orbital (HOMO) while having a higher lowest unoccupied molecular orbital (LUMO) by minimizing the warping of the molecule, and thus it is possible to easily adjust the electron balance within the light-emitting layer when it is applied to a light-emitting auxiliary layer, thereby being advantageous in improving efficiency and lifespan.

[0082] Further, the above Chemical Formula 1 can be represented by the following Chemical Formula 4:

[0083] <Chemical Formula 4>

[0084]

[0085] In the above Chemical Formula 4,

[0086] Ar2, L2, R1 to R4, l, m, and n are defined the same as in Chemical Formula 1 above,

[0087] R and R' are each independently a substituted or unsubstituted C1 to C6 alkyl, a substituted or unsubstituted C6 to C30 aryl, or a substituted or unsubstituted C2 to C30 heteroaryl,

[0088] L2 is attached to any one of the * positions.

[0089] As described above, the compound represented by Chemical Formula 4 according to the present application has a structure in which the terminal of the amine group, i.e., Ar1, is limited to a phenyl group, thereby enabling enhancement of π-conjugation and thereby formation of a higher lowest unoccupied molecular orbital (LUMO) and maintenance of a higher T1. In addition, the above-described compound can exhibit faster hole mobility, and can ensure excellent molecular arrangement when a thin film is formed, thereby enabling low driving voltage, high efficiency, and long service life by suppression of a degradation phenomenon.

[0090] Meanwhile, the above-described Chemical Formula 1 can be represented by the following Chemical Formula 5 or Chemical Formula 6:

[0091] <Chemical Formula 5>

[0092]

[0093] <Chemical Formula 6>

[0094]

[0095] In the above-described Chemical Formula 5 and Chemical Formula 6,

[0096] Ar1, Ar2, R1 to R4, l, m, and n are defined identically to those in the above-described Chemical Formula 1,

[0097] R and R' are each independently a substituted or unsubstituted C1 to C6 alkyl group, a substituted or unsubstituted C6 to C30 aryl group, or a substituted or unsubstituted C2 to C30 heteroaryl group,

[0098] o is an integer of 0 to 2.

[0099] wherein Ar1 can be a phenyl group or a naphthyl group, specifically a phenyl group.

[0100] As described above, the compound represented by Chemical Formula 5 according to the present application has a structure in which L2 is directly bonded or includes one or more phenylene groups and the bonding position of the fluorene group is limited to position 3, compared to the compound of Chemical Formula 3, and can ensure excellent thin film arrangement of the molecule by minimizing the warping of the fluorene group and effectively improve mobility, thereby enabling maintenance of higher efficiency of the organic light emitting element and driving improvement effect.

[0101] In addition, the compound represented by Chemical Formula 6 according to the present application has a structure in which L2 is directly bonded or includes one or more phenylene groups and the bonding position of the fluorene group is limited to position 4, compared to the compound of Chemical Formula 3, can form a deeper highest occupied molecular orbital (HOMO) and a higher lowest unoccupied molecular orbital (LUMO), and can also more easily form an exciton in the light emitting layer by maintaining a higher T1, thereby effectively maintaining the driving voltage of the organic light emitting element and improving efficiency.

[0102] Further, in the above Chemical Formula 5 and / or Chemical Formula 6, since the compound in which o is 1 or 2 has a structure in which a fluorene group is bonded to an amine group through two or more phenylene groups, it is possible to prevent recrystallization of a thin film by maintaining a high glass transition temperature (Tg) and thereby achieve driving stability.

[0103] On the contrary, in the above Chemical Formula 5 and / or Chemical Formula 6, the compound in which o is 0, i.e., L2 is directly bonded, can achieve the effect of forming a deeper highest occupied molecular orbital (HOMO) and a higher lowest unoccupied molecular orbital (LUMO).

[0104] Further, in any one of the above Chemical Formula 1 to Chemical Formula 6,

[0105] The above R and R' can be a methyl group or a phenyl group, and the compound of the present application satisfying the above condition can have a lower deposition temperature, and can effectively improve a driving voltage by minimizing the volume property.

[0106] Further, the above Ar2 can be a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a phenanthryl group, or a triphenylene group, and can include an ortho-phenylene group (1,2-phenylene group) or a meta-phenylene group (1,3-phenylene group).

[0107] As an example, the above Ar2 can include any one of the substituents represented by the structures of Structural Formula A-1 to A-13 below:

[0108]

[0109] In particular, the above Ar2 can be a substituent of the structure represented by Structural Formula A-2 or A-4.

[0110] According to the compound represented by any one of Chemical Formula 1 to Chemical Formula 5 of the present application, since Ar2 includes a phenyl group, a biphenyl group, a terphenyl group, etc., it is possible to ensure excellent thin film alignment of a molecule by minimizing the volume property of the end portion expanded, and effectively improve the Hall mobility, and thereby it is possible to improve the service life by driving and suppressing the deterioration phenomenon.

[0111] In particular, in the case where Ar2 includes an ortho-phenylene group (1,2-phenylene group) or a meta-phenylene group (1,3-phenylene group), since it is possible to lower the deposition temperature, it is advantageous in terms of thermal stability, and it is also possible to form a deeper highest occupied molecular orbital (HOMO) and a higher lowest unoccupied molecular orbital (LUMO) and T1, and thereby it is possible to effectively improve the efficiency of the organic light emitting element.

[0112] Further, the above R1 to R4 can each independently be hydrogen, deuterium, a methyl group, a phenyl group, a biphenyl group, or a naphthyl group.

[0113] The compound of the present application satisfying the above conditions is effective in improving efficiency because it can form a higher lowest unoccupied molecular orbital (LUMO) while having a deeper highest occupied molecular orbital (HOMO) and T1, and is also advantageous in terms of thermal stability because it can reduce the deposition temperature.

[0114] Further, the above Chemical Formula 1 can be represented by the following Chemical Formula 7.

[0115] <Chemical Formula 7>

[0116]

[0117] In the above Chemical Formula 7,

[0118] The definitions of Ar1, Ar2, R1 to R4, l, m, and n are the same as the definition 1 in the above Chemical Formula, and R and R' can each independently be a substituted or unsubstituted C1 to C6 alkyl group, a substituted or unsubstituted C6 to C30 aryl group, or a substituted or unsubstituted C2 to C30 heteroaryl group.

[0119] As described above, because the compound represented by Chemical Formula 7 according to the present application has a structure in which L2 is directly bonded and the bonding position of the fluorenyl group is limited to the 4th position, it can form a deeper highest occupied molecular orbital (HOMO) and a higher lowest unoccupied molecular orbital (LUMO), and also can more easily form an exciton in the light-emitting layer by maintaining a higher T1, thereby effectively maintaining the driving voltage of the organic light-emitting element and improving efficiency.

[0120] The following compounds are specific examples of the compound according to the present application. The following examples are merely illustrative of the present application and do not limit the present application.

[0121]

[0122]

[0123]

[0124]

[0125]

[0126]

[0127]

[0128]

[0129]

[0130]

[0131]

[0132]

[0133]

[0134]

[0135]

[0136]

[0137]

[0138]

[0139]

[0140]

[0141]

[0142]

[0143]

[0144]

[0145]

[0146]

[0147]

[0148]

[0149]

[0150]

[0151]

[0152]

[0153]

[0154]

[0155]

[0156]

[0157]

[0158]

[0159]

[0160]

[0161]

[0162]

[0163]

[0164]

[0165]

[0166]

[0167]

[0168]

[0169]

[0170]

[0171]

[0172]

[0173]

[0174]

[0175] Further, another embodiment of the present application provides an organic light emitting element including the compound represented by Chemical Formula 1 above. The above organic light emitting element can include one or more organic layers containing the compound according to the present application between a first electrode and a second electrode.

[0176] In an embodiment of the present application, the above organic layer can be one or more of a hole injection layer, a hole transport layer, and a light emitting auxiliary layer, for example, can be a light emitting auxiliary layer, but is not limited thereto. At this time, the compound of the present application can be used alone or together with a known organic light emitting compound.

[0177] In the present application, the light-emitting auxiliary layer refers to a layer formed between the hole-transporting layer and the light-emitting layer, and the hole-transporting layer can be referred to as the 2nd hole-transporting layer or the 3rd hole-transporting layer, etc. according to the number thereof.

[0178] Specifically, the organic light-emitting element of the present application can include one or more organic layers such as a hole-injection layer (HIL), a hole-transporting layer (HTL), a light-emitting layer (EML), an electron-transporting layer (ETL), and an electron-injection layer (EIL) between the 1st electrode and the 2nd electrode.

[0179] FIG. 1 is a schematic diagram illustrating the configuration of the organic light-emitting element according to an embodiment of the present application.

[0180] As shown in FIG. 1 , the organic light-emitting element of the present application can be manufactured by sequentially stacking the 1st electrode (hole-injection electrode) 1000, the hole-injection layer 200, the hole-transporting layer 300, the light-emitting layer 400, the electron-transporting layer 500, the electron-injection layer 600, and the 2nd electrode (electron-injection electrode) 2000 in this order from the lower portion to the upper portion of the substrate 100.

[0181] In addition, although not illustrated, a hole-blocking layer (illustration omitted) can be further included between the light-emitting layer 400 and the electron-transporting layer 500, and an electron-blocking layer (illustration omitted) can be further included between the hole-transporting layer 300 and the light-emitting layer 400.

[0182] In addition, a cover layer (illustration omitted) can be further included between the substrate 100 and the 1st electrode 1000, and a cover layer (illustration omitted) can be further included on the upper portion of the 2nd electrode 2000.

[0183] FIG. 1 The substrate 100 can use a substrate used in an organic light-emitting element, and in particular, a transparent glass substrate or a flexible plastic substrate having excellent mechanical strength, thermal stability, transparency, surface smoothness, handling convenience, and water resistance can be used.

[0184] The 1st electrode 1000 is used as an anode for injecting holes in the organic light-emitting element. In order to achieve the injection of holes, a substance having a work function as low as possible is used, and can be formed using a transparent material such as indium tin oxide (ITO), indium zinc oxide (IZO), and graphene.

[0185] Above the first electrode, a hole injection layer 200 can be formed by depositing a hole injection layer material using methods such as vacuum deposition, spin coating, casting, or the Langmuir-Blodgett (LB) method. When forming the hole injection layer using vacuum deposition, the deposition conditions will vary depending on the compound used as the hole injection layer material, the desired hole injection layer structure, and its thermal properties. Typically, deposition temperatures ranging from 50 to 500°C and 10... -8 Up to 10 -3 The vacuum level of the Torr is 0.01 to... Deposition rate and Appropriate selection should be made within the range of layer thickness up to 5 μm.

[0186] Next, on top of the aforementioned hole injection layer 200, a hole transport layer 300 can be formed by depositing a hole transport layer material using methods such as vacuum deposition, spin coating, casting, or the Langmuir-Brønder (LB) method. When forming the hole transport layer using the aforementioned vacuum deposition method, the deposition conditions will vary depending on the compound used, but are generally preferably selected within a range of conditions almost identical to those used for forming the hole injection layer. There can be more than one hole transport layer; for example, it can be two layers, such as a first hole transport layer and a second hole transport layer (luminescent auxiliary layer). At least one of the aforementioned first hole transport layer and second hole transport layer can include a compound of Chemical Formula 1 according to the present invention.

[0187] Next, on top of the aforementioned hole transport layer or luminescent auxiliary layer, a luminescent layer 400 can be formed by depositing a luminescent layer material using methods such as vacuum deposition, spin coating, casting, or the Langmuir-Brønder (LB) method. When forming the luminescent layer using the aforementioned vacuum deposition method, the deposition conditions will vary depending on the compound used, but it is generally preferable to select conditions within a range almost identical to those used for forming the hole injection layer. Furthermore, known compounds can be used as the main agent or dopant as the luminescent layer material.

[0188] Further, when a phosphorescent dopant is used in the light-emitting layer, in order to prevent the phenomenon of diffusion of triplet excitons or holes to the electron-transporting layer, a hole-blocking material (HBL) can be additionally layered by a vacuum deposition method or a spin coating method. At this time, the hole-blocking material used is not particularly limited, and any known material used as a hole-blocking material can be used. For example, oxadiazole derivatives or benzotriazole derivatives, phenanthroline derivatives, or hole-blocking materials described in Japanese Patent Application Publication No. 11-329734 (A1), among which the most representative include Balq (bis(8-hydroxy-2-methylquinoline)-(4-phenylphenoxy)aluminum), phenanthrolines (e.g., BCP (bathocuproin) of UDC, Inc.), and the like can be used.

[0189] An electron-transporting layer 500 is formed on the upper portion of the light-emitting layer 400 formed in the above-described manner, and at this time, the electron-transporting layer can be formed by a method such as a vacuum deposition method, a spin coating method, a casting method, or the like. Further, the deposition conditions of the electron-transporting layer vary depending on the compound used, but are generally selected within a range of conditions almost the same as those for the formation of the hole-injecting layer.

[0190] Next, an electron-injecting layer 600 can be formed by depositing an electron-injecting layer material on the upper portion of the electron-transporting layer 500, and at this time, the electron-injecting layer can be formed by a method such as a vacuum deposition method, a spin coating method, a casting method, or the like, using a general electron-injecting layer material.

[0191] The hole-injecting layer 200, the hole-transporting layer 300, the light-emitting layer 400, and the electron-transporting layer 500 of the organic light-emitting element described above can use the compound according to the present application or the material described in Table 1 below, or can use the compound according to the present application and a known material together.

[0192] [Table 1]

[0193]

[0194] On the upper portion of the electron-injecting layer 600, a second electrode 2000 can be formed by a method such as a vacuum deposition method or a spin coating method. As the second electrode, various metals can be used. As specific examples, materials such as aluminum, gold, silver, and the like are included.

[0195] As the organic light-emitting element according to the present application, not only an organic light-emitting element composed of a first electrode (anode), a hole-injecting layer, a hole-transporting layer, a light-emitting layer, an electron-transporting layer, an electron-injecting layer, and a second electrode (cathode) can be used, but also an organic light-emitting element of various structures can be used, and an intermediate layer of one or two layers can be additionally formed as needed.

[0196] The thickness of each organic layer formed by the present application can be adjusted according to the degree required, and specifically can be 10 to 1000 nm, more specifically 30 to 100 nm.

[0197] Further, the present application can adjust the thickness of the organic layer in molecular units in the organic layer including the compound represented by Chemical Formula 1 above, and thus has the advantages of a uniform surface and excellent morphological stability.

[0198] Next, the present application will be described in more detail through a synthesis example of a compound according to an embodiment of the present application and a manufacturing example of an organic light emitting element. The following examples are merely for exemplification of the present application, and the scope of the present application is not limited to the following examples.

[0199] <SYNTHESIS EXAMPLE 1> Synthesis of Compound 45

[0200]

[0201] After reflux stirring was performed in a round bottom flask into which 80 ml of toluene was injected and 3.0 g of 3-(2-bromophenyl)-9,9-diphenyl-9H-fluorene, 1.6 g of N-phenyl-[1,1'-biphenyl]-4-amine, 0.9 g of t-BuONa, 0.2 g of Pd2(dba)3, and 0.3 ml of (t-Bu)3P were dissolved, the reaction degree was confirmed using thin layer chromatography (TLC) and the reaction was ended after water was added. The organic layer was extracted using dichloromethane (MC) and after filtration under reduced pressure, column purification and recrystallization were performed, thereby obtaining 2.8 g of Compound 45 (yield: 69%).

[0202] m / z: 637.28 (100.0%), 638.28 (53.4%), 639.28 (14.0%), 640.29 (2.4%).

[0203] <SYNTHESIS EXAMPLE 2> Synthesis of Compound 249

[0204]

[0205] The same method as in Synthesis Example 1 was performed, except that 4-(2- bromophenyl)-9,9-diphenyl-9H-fluorene was used instead of 3-(2-bromophenyl)-9,9- diphenyl-9H-fluorene, to synthesize Compound 249 (yield 63%).

[0206] m / z: 637.28 (100.0%), 638.28 (53.4%), 639.28 (14.0%), 640.29 (2.4%)

[0207] <Synthesis Example 3> Synthesis of Compound 271

[0208]

[0209] The same method as in Synthesis Example 1 was performed, except that 4-(2- bromophenyl)-9,9-diphenyl-9H-fluorene and N-phenyl-[1,1':4',1"-terphenyl]-4- amine were used instead of 3-(2-bromophenyl)-9,9-diphenyl-9H-fluorene and N- phenyl-[1,1'-biphenyl]-4-amine, to synthesize Compound 271 (yield 65%).

[0210] m / z: 713.31 (100.0%), 714.31 (60.3%), 715.31 (17.6%), 716.32 (3.4%)

[0211] <Synthesis Example 4> Synthesis of Compound 272

[0212]

[0213] The same method as in Synthesis Example 1 was performed, wherein 4-(2- bromophenyl)-9,9-diphenyl-9H-fluorene and N-phenyl-[1,1':3',1"-terphenyl]-4- amine were used instead of 3-(2-bromophenyl)-9,9-diphenyl-9H-fluorene and N- phenyl-[1,1'-biphenyl]-4-amine, to synthesize Compound 272 (yield: 65%).

[0214] m / z: 713.31 (100.0%), 714.31 (60.3%), 715.31 (17.6%), 716.32 (3.4%)

[0215] <Synthesis Example 5> Synthesis of Compound 277

[0216]

[0217] The same method as in Synthesis Example 1 was performed, wherein 4-(2- bromophenyl)-9,9-diphenyl-9H-fluorene and N-phenyl-[1,1':4',1"-terphenyl]-2- amine were used instead of 3-(2-bromophenyl)-9,9-diphenyl-9H-fluorene and N- phenyl-[1,1'-biphenyl]-4-amine, to synthesize Compound 277 (yield: 63%).

[0218] m / z: 713.31 (100.0%), 714.31 (60.3%), 715.31 (17.6%), 716.32 (3.4%)

[0219] <Synthesis Example 6> Synthesis of Compound 362

[0220]

[0221] The same method as in Synthesis Example 1 was performed, wherein 4-(2'-bromo-[l,l'-biphenyl]-4-yl)-9,9-diphenyl-9H-fluorene was used instead of 3-(2-bromophenyl)-9,9-diphenyl-9H-fluorene to synthesize Compound 362 (yield: 60%).

[0222] m / z: 713.31 (100.0%), 714.31 (60.3%), 715.31 (17.6%), 716.32 (3.4%)

[0223] Manufacture of organic light emitting element

[0224] The organic light emitting element of the present application was manufactured using the materials tabulated in Table 2 below.

[0225]

Table 2

[0226]

[0227] <Example 1>

[0228] A glass substrate having an indium tin oxide (ITO) thin film coated thereon with a thickness of 1500 A was subjected to ultrasonic washing with distilled water. After completion of the distilled water washing, ultrasonic washing and drying were performed using a solvent such as isopropyl alcohol, acetone, methanol, etc., and next, the substrate was subjected to cleaning using oxygen plasma for 5 minutes in a plasma cleaning machine, and then, on the upper portion of the indium tin oxide (ITO) substrate, a film of HIOl of Formula 1 and a film of HATCN of Formula 2 were formed as a hole injection layer, and a film of HTOl of Formula 3 was formed as a hole transport layer, and a film of the compound manufactured in Synthesis Example 1 of Formula 4 was formed as a light emitting auxiliary layer, and a film of BH01:BD01 3% doped was formed as a light emitting layer. Next, a film of ET01:Liq (1:1) of Formula 5 was formed as an electron transport layer, and a film of LiF of Formula 6 and a film of aluminum (Al) of Formula 7 were formed, and then, the element was encapsulated in a glove box to manufacture an organic light emitting element.

[0229] ​<Example 2> to <Example 6>

[0230] An organic light emitting element was produced in the same manner as in Example 1 above, using the compound produced in Synthesis Example 2 to deposit the light emitting auxiliary layer.

[0231] <Comparative Example 1> to <Comparative Example 6>

[0232] An organic light emitting element was produced in the same manner as in Example 1 above, using the following Comparative Compound 1 (Ref. 1) to Comparative Compound 6 (Ref. 6) shown in Table 3 below to deposit the light emitting auxiliary layer, respectively.

[0233] [Table 3]

[0234]

[0235] Performance evaluation of organic light emitting element

[0236] The performance of the organic light emitting elements of the Examples and Comparative Examples, i.e. the current density and luminance with respect to the applied voltage, was evaluated under atmospheric pressure conditions by injecting electrons and holes by loading a voltage to a Kiethley 2400 source measurement unit and measuring the luminance when light was emitted using a Konica Minolta spectroradiometric luminance meter (CS-2000), and the results are shown in Table 4.

[0237] [Table 4]

[0238] Op.V mA / cm 2 ]] Cd / A QE (%) CIEx CIEy LT95 Example 1 3.34 10 8.2 7.0 0.139 0.110 163 Example 2 3.37 10 8.8 7.7 0.140 0.109 171 Example 3 3.36 10 8.7 7.5 0.140 0.110 176 Example 4 3.37 10 8.9 8.0 0.142 0.110 180 Example 5 3.38 10 9.1 8.1 0.140 0.109 178 Example 6 3.34 10 8.1 7.0 0.139 0.109 161 Comparative Example 1 3.41 10 6.8 5.7 0.140 0.111 110 Comparative Example 2 3.48 10 7.3 6.2 0.141 0.109 85 Comparative Example 3 3.43 10 7.2 6.0 0.140 0.110 116 Comparative Example 4 3.45 10 7.6 6.5 0.142 0.110 121 Comparative Example 5 3.42 10 7.1 6.0 0.140 0.110 95 Comparative Example 6 3.42 10 7.0 5.8 0.140 0.110 92

[0239] It can be seen from the Examples of the present application that the organic light emitting elements of the Examples not only achieve a lower driving voltage, but also have a very excellent light emitting efficiency improvement effect.

[0240] Specifically, it can be confirmed that the organic light emitting elements according to the Examples of the present application have a deeper highest occupied molecular orbital (HOMO) compared to the organic light emitting elements of Comparative Examples 1 to 3 because the compound in which the ortho linking group is introduced at the 1st, 3rd or 4th position of the fluorene group is contained in the light emitting auxiliary layer. Thereby, the organic light emitting elements of the Examples can maintain a faster Hall mobility, thereby achieving a lower voltage and a higher efficiency.

[0241] Further, the organic light emitting element of the above-described embodiment is different from Comparative Example 4 in that the light emitting auxiliary layer contains a compound having an unexpanded aryl group on one side of the amine, and thus has a deeper highest occupied molecular orbital (HOMO) value and a higher lowest unoccupied molecular orbital (LUMO) and T1. Further, the organic light emitting element of the embodiment is different from Comparative Example 5 and Comparative Example 6 in that, as the compound of the light emitting auxiliary layer, a methylfluorenyl group or a carbazolyl group that functions as an electron donor is not substituted into the amine group, and thus a deeper highest occupied molecular orbital (HOMO) can be maintained.

[0242] Accordingly, the organic light emitting element of the embodiment can effectively improve the Hall mobility, and at the same time, can easily achieve the movement interception of electrons and excitons and excellent charge balance within the light emitting layer. Further, the above-described organic light emitting element can achieve an organic light emitting element having a lower driving voltage, high efficiency, and long service life by suppressing the decay phenomenon.

Claims

1. A compound represented by the following Chemical Formula 1: Chemical Formula 1 In the above Chemical Formula 1, Ar1 is a phenyl group or a naphthyl group; Ar2 is any one of the substituents represented by the following Structural Formulae A-1 to A-11 and A-13; L1 and L2 are each independently a direct bond or a C6 arylene group; R and R' are a phenyl group, R1 to R3 are each independently hydrogen, deuterium, or a C6 aryl group, R4 is hydrogen or deuterium; l is an integer of 0 to 4; m is an integer of 0 to 2; and n is an integer of 0 to 4, but excluding the following compounds:

2. The compound according to claim 1, characterized in that: the above Chemical Formula 1 is a compound represented by the following Chemical Formula 2: Chemical Formula 2 In the above Chemical Formula 2, the definitions of Ar1, Ar2, L1, L2, R, R', R1 to R4, l, m, and n are the same as in the above Chemical Formula 1, L2 is attached to any one of the * positions.

3. The compound according to claim 1, characterized in that: the above Chemical Formula 1 is a compound represented by the following Chemical Formula 3: Chemical Formula 3 In the above Chemical Formula 3, the definitions of Ar1, Ar2, L2, R1 to R4, R, R', l, m, and n are the same as in the above Chemical Formula 1, L2 is attached to any one of the * positions.

4. The compound according to claim 1, characterized in that: the above Chemical Formula 1 is a compound represented by the following Chemical Formula 4: Chemical Formula 4 In the above Chemical Formula 4, the definitions of Ar2, L2, R1 to R4, R, R', l, m, and n are the same as in the above Chemical Formula 1, L2 is attached to any one of the * positions.

5. The compound according to claim 1, characterized in that: the above Chemical Formula 1 is a compound represented by the following Chemical Formula 5 or Chemical Formula 6: Chemical Formula 5 Chemical Formula 6 In the above Chemical Formula 5 and Chemical Formula 6, the definitions of Ar1, Ar2, R1 to R4, R, R', l, m, and n are the same as in the above Chemical Formula 1, o is an integer of 0 to 2 but excluding 2.

6. The compound according to claim 1, characterized in that: Ar2 includes an ortho-phenylene group (1,2-phenylene group) or a meta-phenylene group (1,3-phenylene group).

7. The compound according to claim 1, characterized in that: R1 to R4 are each independently hydrogen or deuterium.

8. The compound according to claim 1, characterized in that: the above Chemical Formula 1 is a compound represented by the following Chemical Formula 7: Chemical Formula 7 In the above Chemical Formula 7, the definitions of Ar1, Ar2, R1 to R4, R, R', l, m, and n are the same as in the above Chemical Formula 1.

9. The compound according to claim 1, characterized in that: the compound of the above Chemical Formula 1 is any one of the compounds represented by the following Chemical Formulae:

10. An organic light emitting element characterized by comprising: including: a first electrode; an organic layer on the above first electrode; and, a second electrode on the above organic layer; the above organic layer contains the compound according to any one of claims 1 to 9.

11. The organic light emitting element according to claim 10, characterized in that: The organic layer is any one or more of a hole injection layer, a hole transport layer, and a light-emitting auxiliary layer.

12. The organic light emitting element according to claim 11, wherein: The organic layer is a light-emitting auxiliary layer between the hole transport layer and the light-emitting layer.

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