Novel compound and organic light-emitting element comprising same
阅读说明：本技术 新型化合物以及包含上述新型化合物的有机发光元件 (Novel compound and organic light-emitting element comprising same ) 是由 咸昊完 安贤哲 金熙宙 金东骏 林东焕 金昇好 李萤振 安慈恩 权桐热 于 2020-10-29 设计创作，主要内容包括：本发明提供一种以下述化学式1表示的化合物以及包含上述化合物的有机发光元件。<化学式1>(The present invention provides a compound represented by the following chemical formula 1 and an organic light emitting device including the same.<Chemical formula 1>)
1. A compound represented by the following chemical formula 1,
chemical formula 1
In the above-described chemical formula 1,
x is C, Si, Ge or Sn,
y is O, S, Se, Te, NAr5N-, orCRR`，
Is L4Or at L4The site that binds to N in the case of direct binding,
r and R 'are each independently hydrogen, deuterium, halogen, nitro, nitrile group, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C2-C30 alkenyl, substituted or unsubstituted C1-C30 alkoxy, substituted or unsubstituted C1-C30 mercapto, substituted or unsubstituted C6-C50 aryl, or substituted or unsubstituted C2-C50 heteroaryl, adjacent R and R' may or may not form a ring with each other,
ar is substituted or unsubstituted aryl of C6-C50 or substituted or unsubstituted heteroaryl of C2-C50,
Ar1is substituted or unsubstituted aryl of C6-C50 or substituted or unsubstituted heteroaryl of C2-C50,
Ar5is substituted or unsubstituted aryl of C6-C50 or substituted or unsubstituted heteroaryl of C2-C50,
L1、L2and L3Each independently is a substituted or unsubstituted arylene group having from C6 to C50, or a substituted or unsubstituted heteroarylene group having from C2 to C50,
L4is directly bonded, substituted or unsubstituted arylene of C6-C50 or substituted or unsubstituted heteroarylene of C2-C50,
R1and R2Each independently is hydrogen, deuterium, halogen, nitro, nitrile group, substituted or unsubstituted C1-C30 alkyl group, substituted or unsubstituted C2-C30 alkenyl group, substituted or unsubstituted C1-C30 alkoxy group, substituted or unsubstituted C1-C30 mercapto group, substituted or unsubstituted C6-C50 aryl group or substituted or unsubstituted C2-C50 heteroaryl group,
R3and R4Each independently is hydrogen, deuterium, halogen, nitro, nitrile group, substituted or unsubstituted C1-C30 alkyl group, substituted or unsubstituted C2-C30 alkenyl group, substituted or unsubstituted C1-C30 alkoxy group, substituted or unsubstituted C1-C30 mercapto group, substituted or unsubstituted C6-C50 aryl group or substituted or unsubstituted C2-C50 heteroaryl group,at a plurality of R3Between or multiple R4May or may not form a ring by bonding to each other,
l is an integer of 0 to 3,
m is an integer of 0 to 4.
2. The compound of claim 1, wherein:
the chemical formula 1 is a compound represented by the following chemical formula 2,
chemical formula 2
In the above-described chemical formula 2,
to Ar, Ar1、R1、R2、R3、R4、L4Y, l and m are as defined in the above chemical formula 1,
x is C or Si, and X is C or Si,
to R5Are each independently defined as R in the above chemical formula 13And R4Is as defined in (1), wherein R5The number of carbon atoms of (A) is satisfied at L1、L2And L3The range of the number of carbons as defined in (1),
n is an integer of 0 to 4,
o is an integer of 3 to 5.
3. The compound of claim 1, wherein:
the chemical formula 1 is a compound represented by the following chemical formula 3,
chemical formula 3
In the above-mentioned chemical formula 3,
to Ar, Ar1、Ar5、R1、R2、R3、R4、L4Y, l and m are as defined in the above chemical formula 1,
x is C or Si, and X is C or Si,
to R5Are each independently defined as R in the above chemical formula 13And R4Is as defined in (1), wherein R5The number of carbon atoms of (A) is satisfied at L1、L2And L3The range of the number of carbons as defined in (1),
each n is independently an integer of 0 to 4.
4. The compound of claim 1, wherein:
the chemical formula 1 is a compound represented by the following chemical formula 4,
chemical formula 4
In the above-mentioned chemical formula 4,
to Ar, Ar1、R1、R2、R3、R4L and m are as defined in the above chemical formula 1,
x is C or Si, and X is C or Si,
to R5、R6And R7Are each independently defined as R in the above chemical formula 13And R4Is as defined in (1), wherein R5The number of carbon atoms of (A) is satisfied at L1、L2And L3In the carbon number range defined in (1), and R6And R7Satisfies the carbon number range defined in Y,
each n is independently an integer of 0 to 4,
p and q are each independently an integer of 0 to 5,
the dashed connections represent direct bonds or non-direct bonds.
5. The compound of claim 4, wherein:
x is Si.
6. The compound of claim 1, wherein:
r, R' and R mentioned above3To R5Each independently hydrogen, deuterium, methyl or phenyl.
7. The compound of claim 1, wherein:
y is O, S, Se, Te, NAr5Or in the case of N-, L4Instead of being directly bonded to each other,
and L in the case where Y is CRR4Is a direct bond.
8. The compound of claim 1, wherein:
l above1、L2And L3Any one or more of them is a1, 3-phenylene group having a meta bond or a1, 2-phenylene group having an ortho bond.
9. The compound of claim 8, wherein:
l above3Is 1, 4-phenylene with para-bonding.
10. The compound of claim 1, wherein:
ar is selected from the group consisting of phenyl, naphthyl, biphenyl, terphenyl, phenanthryl, terphenyl, dimethylfluorenyl, diphenylfluorenyl, spirobifluorenyl, dibenzofuranyl, dibenzothienyl, carbazolyl, and combinations thereof.
11. The compound of claim 10, wherein:
ar is phenyl, naphthyl or biphenyl.
12. The compound of claim 1, wherein:
ar above1、R1And R2Is phenyl.
13. The compound of claim 1, wherein:
the chemical formula 1 is any one of the following chemical formulas,
14. an organic light-emitting element comprising the compound according to any one of claims 1 to 13.
15. The organic light-emitting element according to claim 14, wherein:
the compound is contained in an organic layer of at least one of the hole injection layer, the hole transport layer, and the light emission auxiliary layer.
16. The organic light-emitting element according to claim 14, wherein:
the compound is contained in a light-emission auxiliary layer located between the hole transport layer and the light-emitting layer.
Technical Field
The present invention relates to a novel compound and an organic light-emitting element including the same.
Background
Recently, a self-luminous organic light emitting device capable of being driven at a low voltage has been attracting attention as a next-generation display device because it is superior to a Liquid Crystal Display (LCD), which is a mainstream of a flat display device, in view angle and contrast ratio, does not require a backlight, can be reduced in weight and thickness, consumes less power, has a wide color reproduction range, and the like.
Materials used as an organic layer in an organic light emitting diode can be broadly classified into a light emitting layer material, a hole injection material, a hole transport material, an electron injection material, and the like according to their functions.
The light-emitting material may be classified into a polymer and a monomolecular according to molecular weight, and may be classified into a fluorescent material derived from a singlet excited state of electrons, a phosphorescent material derived from a triplet excited state of electrons, and a delayed fluorescent material derived from electron transfer from a triplet excited state to a singlet excited state according to a light-emitting mechanism, and the light-emitting material may be classified into blue and green light-emitting materials, and yellow and vermilion light-emitting materials required for realizing a natural color more excellent than that of a red light-emitting material according to light-emitting colors.
In addition, in order to improve color purity and luminous efficiency by energy transfer, a host/dopant substance may be used as the light-emitting substance. The principle is that a dopant, which is a light-emitting substance having an energy band gap smaller than that of the host, is mixed into the light-emitting layer in a small amount, so that excitons generated in the host are transferred to the dopant and light is emitted. By the principle as described above, light of a desired wavelength can be obtained depending on the types of the host and the dopant.
Many compounds have been known as substances suitable for the above organic light emitting element, but since the organic light emitting element using the substances known so far has problems such as high driving voltage, low efficiency, and short lifetime, development of a novel material is still required. Therefore, there have been efforts to develop an organic light emitting element that can be driven at a low voltage, has high luminance, and has a long lifetime, using a substance having excellent characteristics.
Disclosure of Invention
The present invention aims to provide a novel compound and an organic light-emitting element that can ensure excellent molecular alignment and faster hall mobility when forming a thin film by forming an appropriate Highest Occupied Molecular Orbital (HOMO) and increasing pi conjugation.
Further, it is an object of the present invention to provide a novel compound and an organic light emitting device which can realize a long lifetime organic light emitting device by forming a high Lowest Unoccupied Molecular Orbital (LUMO) and T1 by combining 3 rings having excellent electron tolerance on the nitrogen side of an aromatic amine and thereby easily realizing electron interception and exciton interception, and thereby realizing excellent charge balance, a low driving voltage, high efficiency, and suppression of a decay phenomenon in a light emitting layer.
Further, it is an object of the present invention to provide a novel compound and an organic light emitting element which can achieve a high glass transition temperature (Tg) by introducing a bulky group having extended to 3 or more linking groups and a 3-ring bonded to nitrogen of an arylamine, thereby preventing recrystallization of a thin film and thereby achieving excellent driving stability.
Next, the above-described problems and additional problems will be described in detail.
As a means for solving the above-mentioned problems,
an embodiment of the present invention provides a compound represented by the following chemical formula 1.
< chemical formula 1>
In the above-described chemical formula 1,
x is C, Si, Ge or Sn,
y is O, S, Se, Te, NAr5N-, or CRR',
wherein-is L4Or at L4The site that binds to N in the case of direct binding,
r and R 'are each independently hydrogen, deuterium, halogen, nitro, nitrile group, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C2-C30 alkenyl, substituted or unsubstituted C1-C30 alkoxy, substituted or unsubstituted C1-C30 mercapto, substituted or unsubstituted C6-C50 aryl, or substituted or unsubstituted C2-C50 heteroaryl, adjacent R and R' may or may not form a ring with each other,
ar is substituted or unsubstituted aryl of C6-C50 or substituted or unsubstituted heteroaryl of C2-C50,
Ar1is substituted or unsubstituted aryl of C6-C50 or substituted or unsubstituted heteroaryl of C2-C50,
Ar5is substituted or unsubstituted aryl of C6-C50 or substituted or unsubstituted heteroaryl of C2-C50,
L1、L2and L3Each independently is a substituted or unsubstituted arylene group having from C6 to C50, or a substituted or unsubstituted heteroarylene group having from C2 to C50,
L4is directly bonded, substituted or unsubstituted arylene of C6-C50 or substituted or unsubstituted heteroarylene of C2-C50,
R1and R2Each independently is hydrogen, deuterium, halogen, nitro, nitrile group, substituted or unsubstituted C1-C30 alkyl group, substituted or unsubstituted C2-C30 alkenyl group, substituted or unsubstituted C1-C30 alkoxy group, substituted or unsubstituted C1-C30 mercapto group, substituted or unsubstituted C6-C50 aryl group, orSubstituted or unsubstituted C2-C50 heteroaryl,
R3and R4Each independently is hydrogen, deuterium, halogen, nitro, nitrile group, substituted or unsubstituted C1-C30 alkyl group, substituted or unsubstituted C2-C30 alkenyl group, substituted or unsubstituted C1-C30 alkoxy group, substituted or unsubstituted C1-C30 mercapto group, substituted or unsubstituted C6-C50 aryl group or substituted or unsubstituted C2-C50 heteroaryl group, in a plurality of R3Between or multiple R4May or may not form a ring by bonding to each other,
l is an integer of 0 to 3,
m is an integer of 0 to 4.
In addition, the present invention provides an organic light-emitting element including the above compound. The compound may be contained in an organic layer including at least one of the hole injection layer, the hole transport layer, and the light emission auxiliary layer, and the compound may be contained in the light emission auxiliary layer located between the hole transport layer and the light emitting layer.
According to the compound and the organic light-emitting element of the present invention, it is possible to form the Highest Occupied Molecular Orbital (HOMO) suitable for the light-emission auxiliary layer and promote pi-conjugation by bonding the triarylmethyl group or triarylsilyl group to the nitrogen of the aromatic amine through 3 or more linking groups, thereby ensuring excellent molecular alignment and faster hall mobility when forming a thin film.
In addition, the present invention can realize a long-life organic light emitting element by excellent charge balance within a light emitting layer, low driving voltage, high efficiency, and suppression of a roll-off phenomenon by forming a high Lowest Unoccupied Molecular Orbital (LUMO) and T1 by combining 3 rings excellent in electron resistance on the nitrogen side of an aromatic amine and thereby easily realizing electron interception and exciton interception.
Further, as described above, the present invention can achieve a high glass transition temperature (Tg) by introducing a bulky group having extended to 3 or more linking groups and a 3-ring bonded to the nitrogen of the arylamine, thereby preventing recrystallization of the film and thereby achieving excellent driving stability.
Next, the effects described above and the additional effects will be described in detail.
Drawings
Fig. 1 is a cross-sectional view schematically illustrating the configuration of an organic light-emitting element according to an embodiment of the present invention.
[ notation ] to show
100: substrate
200: hole injection layer
300: hole transport layer
400: luminescent layer
500: electron transport layer
600: electron injection layer
1000: anode (No. 1 electrode)
2000: cathode (No. 2 electrode)
Detailed Description
Before explaining the present invention in detail, it is to be understood that the terminology used in the description is for the purpose of describing particular embodiments only, and is not intended to limit the scope of the present invention which will be limited only by the scope of the appended claims. Unless otherwise specifically stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art.
Throughout this specification and the claims which follow, unless the context clearly dictates otherwise, the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated item, step, or series of items or steps but not the exclusion of any other item, step, or series of items or steps.
Throughout this specification and the claims, the term "aryl" is meant to include, for example, phenyl, benzyl, naphthyl, biphenyl, terphenyl, fluorenyl, phenanthryl, triphenylene, phenylene, perylene, and,Fluoranthenyl, benzofluorenyl, benzotriazolylPhenyl, benzoAryl groups having 5 to 50 carbon atoms in the aromatic ring such as an anthracene group, stilbene group and pyrenyl group, and "heteroaryl" includes, for example, a pyrrolyl group, a pyrazinyl group, a pyridyl group, an indolyl group, an isoindolyl group, a furyl group, a benzofuryl group, an isobenzofuryl group, a dibenzofuryl group, a benzothienyl group, a dibenzothienyl group, a quinolyl group, an isoquinolyl group, a quinoxalyl group, a carbazolyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a thienyl group, a pyridyl ring, a pyrazine ring, a pyrimidine ring, a pyridazine ring, a triazine ring, an indole ring, a quinoline ring, an acridine ring, a pyrrolidine ring, a diazine ring, a phenanthrolineAn alkyl ring, a piperidine ring, a morpholine ring, a piperazine ring, a carbazole ring, a furan ring, a thiophene ring,An azolyl ring,Diazole ring, benzoAnd a heterocyclic group consisting of an azole ring, a thiazole ring, a thiadiazole ring, a benzothiazole ring, a benzotriazole ring, an imidazole ring, a benzimidazole ring, a pyran ring and a dibenzofuran ring, wherein the heterocyclic group is an aromatic ring having 2-50 carbon atoms and containing at least one hetero element.
Throughout the present specification and claims, the term "substituted or unsubstituted" means substituted or unsubstituted with a substituent selected from the group consisting of deuterium, halogen, amino, cyano, nitrile, nitro, nitroso, sulfamoyl, isothiocyanate, thiocyanate, carboxyl, or C1-C30 alkyl, C1-C30 alkylsulfinyl, C1-C30 alkylsulfonyl, C1-C30 alkylsulfanyl, C1-C12 fluoroalkyl, C2-C30 alkenyl, C1-C30 alkoxy, C1-C12N-alkylamino, C2-C20N, N-dialkylamino, C1-C6N-alkylsulfamoyl, C2-C12N, n-dialkyl sulfamoyl, silyl of C3-C30, cycloalkyl of C3-C20, heteroalkyl of C3-C20, aryl of C6-C50, heteroaryl of C3-C50, and the like. In addition, throughout the specification of the present application, the same symbols have the same meaning unless explicitly stated otherwise.
Moreover, various embodiments of the invention may be combined with other certain embodiments, unless explicitly stated to the contrary. Next, embodiments of the present invention and effects thereof will be explained.
Next, the present invention will be described in detail.
The compound according to the present invention is represented by the following chemical formula 1.
< chemical formula 1>
In the above-described chemical formula 1,
x is C, Si, Ge or Sn,
y is O, S, Se, Te, NAr5N-, or CRR',
wherein-is L4Or at L4The site that binds to N in the case of direct binding,
r and R 'are each independently hydrogen, deuterium, halogen, nitro, nitrile group, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C2-C30 alkenyl, substituted or unsubstituted C1-C30 alkoxy, substituted or unsubstituted C1-C30 mercapto, substituted or unsubstituted C6-C50 aryl, or substituted or unsubstituted C2-C50 heteroaryl, adjacent R and R' may or may not form a ring with each other,
ar is substituted or unsubstituted aryl of C6-C50 or substituted or unsubstituted heteroaryl of C2-C50,
Ar1is substituted or unsubstituted aryl of C6-C50 or substituted or unsubstituted heteroaryl of C2-C50,
Ar5is substituted or unsubstituted C6 ℃An aryl group of C50, or a substituted or unsubstituted heteroaryl group of C2 to C50,
L1、L2and L3Each independently is a substituted or unsubstituted arylene group having from C6 to C50, or a substituted or unsubstituted heteroarylene group having from C2 to C50,
L4is directly bonded, substituted or unsubstituted arylene of C6-C50 or substituted or unsubstituted heteroarylene of C2-C50,
R1and R2Each independently is hydrogen, deuterium, halogen, nitro, nitrile group, substituted or unsubstituted C1-C30 alkyl group, substituted or unsubstituted C2-C30 alkenyl group, substituted or unsubstituted C1-C30 alkoxy group, substituted or unsubstituted C1-C30 mercapto group, substituted or unsubstituted C6-C50 aryl group or substituted or unsubstituted C2-C50 heteroaryl group,
R3and R4Each independently is hydrogen, deuterium, halogen, nitro, nitrile group, substituted or unsubstituted C1-C30 alkyl group, substituted or unsubstituted C2-C30 alkenyl group, substituted or unsubstituted C1-C30 alkoxy group, substituted or unsubstituted C1-C30 mercapto group, substituted or unsubstituted C6-C50 aryl group or substituted or unsubstituted C2-C50 heteroaryl group, in a plurality of R3Between or multiple R4May or may not form a ring by bonding to each other,
l is an integer of 0 to 3,
m is an integer of 0 to 4.
Specifically, the chemical formula 1 can be represented by the following chemical formula 2.
< chemical formula 2>
In the above-described chemical formula 2,
to Ar, Ar1、R1、R2、R3、R4、L4Y, l and m are as defined in the above chemical formula 1,
x is C or Si, and X is C or Si,
to R5Are each independently defined as R in the above chemical formula 13And R4Are as defined (wherein, R is5The number of carbon atoms of (A) is satisfied at L1、L2And L3The carbon number range as defined in (1), n is an integer of 0 to 4,
o is an integer of 3 to 5.
In the structure of the above chemical formula 2, the compound can be represented byThe inclusion of 3 to 5 phenylene groups in the linkage between X (e.g. triarylmethyl or triarylsilyl) in (a) and the nitrogen of the arylamine maintains a high T1 and thereby efficiently intercepts excitons.
The chemical formula 1 may be specifically represented by the following chemical formula 3.
< chemical formula 3>
In the above-mentioned chemical formula 3,
to Ar, Ar1、Ar5、R1、R2、R3、R4、L4Y, l and m are as defined in the above chemical formula 1,
x is C or Si, and X is C or Si,
to R5Are each independently defined as R in the above chemical formula 13And R4Are as defined (wherein, R is5The number of carbon atoms of (A) is satisfied at L1、L2And L3The carbon number range as defined in (1), and each n is independently an integer of 0 to 4.
The compound of the above chemical formula 3 is characterized in that L in the above chemical formula 11、L2And L3Are all phenylene radicals, in which the linking group closest to the nitrogen of the aromatic amine is a para-bonded phenylene radical (1, 4-phenylene radical), whereby a faster Hall mobility and a higher mobility can be maintained for the aromatic amineThe attenuation phenomenon is suppressed, thereby effectively improving the service life.
In the above chemical formula 3, Y may be O or S.
In the above chemical formula 3, n may be 0, and m and l may be 1, respectively.
The chemical formula 1 may be specifically represented by the following chemical formula 4.
< chemical formula 4>
In the above-mentioned chemical formula 4,
to Ar, Ar1、R1、R2、R3、R4L and m are as defined in the above chemical formula 1,
x is C or Si, and X is C or Si,
to R5、R6And R7Are each independently defined as R in the above chemical formula 13And R4Are as defined (wherein, R is5The number of carbon atoms of (A) is satisfied at L1、L2And L3In the carbon number range defined in (1), and R6And R7Satisfies the carbon number range defined in Y),
n is each independently an integer of 0 to 4, specifically 0,
p and q are each independently an integer of 0 to 5, and specifically may be 1.
Furthermore, the dashed connections represent bonds that may or may not be directly bonded to each other. In the case of direct bonding to each other, the 3-ring may be spirobifluorenyl.
In the case where the 3-ring is directly bonded to the nitrogen of the aromatic amine and the 3-ring is a diarylfluorene group or a spirobifluorene group, the compound of the above chemical formula 4 can maintain faster hall mobility while forming a deeper Highest Occupied Molecular Orbital (HOMO), thereby effectively achieving low voltage driving and efficiency improvement.
Further, in the above chemical formulas 1 to 4,R、R`、R3to R7May each independently be hydrogen, deuterium, methyl or phenyl. Specifically, hydrogen may be used. Thereby, the driving voltage can be effectively improved by minimizing the volume characteristic.
In addition, in the chemical formulas 1 and 2, in the case where the 3 ring bonded to the nitrogen of the arylamine is a hetero 3 ring such as dibenzofuran or dibenzothiophene, L4May not be directly combined, particularly L4May be a phenylene group.
In contrast, in the above chemical formulas 1 and 2, in the case where the 3-ring bonded to the nitrogen of the arylamine is, for example, a dimethylfluorenyl group, diarylfluorenyl group, spirobifluorenyl group, or the like as in the above chemical formula 4, L4It may be bonded directly, in particular the nitrogen of the arylamine may be bonded directly to the diarylfluorene group in position 2.
That is, in the above chemical formula 1 and chemical formula 2, Y is O, S, Se, Te, NAr5Or in the case of N-, L4Not directly bound, but L in the case of Y being CRR4May be a direct bond.
In addition, in the above chemical formulas 1 to 4, 3 or more linking groups linking X and N may have one or more meta (1, 3-phenylene) or ortho (1, 2-phenylene) linkages.
Specifically, in the chemical formula 1, L is1、L2And L3One or more of which may be phenylene with meta or ortho bonding. More specifically, L1And L2One or more of them being phenylene having meta-or ortho-bonding, L3May be phenylene with a bond in the para position. Thereby, a higher Lowest Unoccupied Molecular Orbital (LUMO) can be formed, thereby effectively improving efficiency through electron interception (it can be confirmed from the subsequent examples that the compounds of examples 2 to 4 having one or more meta-or ortho-bound phenylene groups have higher luminance and more excellent efficiency than the compounds of examples 1 and 5 having only para-bound phenylene groups).
Further, in the above chemical formula 4, X may be Si, in which case efficiency and lifespan may be more effectively improved.
In the chemical formulas 1 to 4, Ar may be selected from the group consisting of phenyl, naphthyl, biphenyl, terphenyl, phenanthryl, terphenyl, dimethylfluorenyl, diphenylfluorenyl, spirobifluorenyl, dibenzofuranyl, dibenzothiophenyl, carbazolyl, and combinations thereof, and specifically may be phenyl, naphthyl, or biphenyl. Thereby, thermal stability can be improved by achieving a lower deposition temperature.
Further, in the above chemical formulas 1 to 4, Ar1、R1And R2May be phenyl. Thereby, a lower deposition temperature can be achieved, while also effectively improving the driving voltage by minimizing the volume characteristic.
In the definitions of chemical formulas 1 to 4, hydrogen may be substituted as a substituent for substitution, but the present invention is not limited thereto, and any of the substituents may be used.
The following compounds are specific examples of the compounds according to the present invention. The following examples are merely illustrative of the present invention and the present invention is not limited thereto.
In addition, another embodiment of the present invention provides an organic light emitting element including the compound represented by chemical formula 1. The organic light emitting element may include 1 or more organic layers containing the compound according to the present invention between the 1 st electrode and the 2 nd electrode.
In an embodiment of the present invention, the organic layer may be 1 or more of the hole injection layer, the hole transport layer, and the light-emission auxiliary layer, and may be, for example, a light-emission auxiliary layer, but is not limited thereto. In this case, the compound of the present invention may be used alone or together with a known organic light emitting compound.
In the present invention, the light emission assisting layer means a layer formed between the hole transporting layer and the light emitting layer, and the hole transporting layer may be referred to as, for example, a 2 nd hole transporting layer or a 3 rd hole transporting layer, depending on the number thereof.
The organic light emitting device may include 1 or more organic layers such as a Hole Injection Layer (HIL), a Hole Transport Layer (HTL), an emission layer (EML), an Electron Transport Layer (ETL), and an Electron Injection Layer (EIL) between a1 st electrode, i.e., an anode (anode), and a 2 nd electrode, i.e., a cathode (cathode).
Specifically, the organic light emitting element can be manufactured as shown in fig. 1. The organic light emitting element may be sequentially laminated to an upper portion of the substrate 100 in the order of anode (hole injection electrode 1000)/hole injection layer 200/hole transport layer 300/light emitting layer 400/electron transport layer 500/electron injection layer 600/cathode (electron injection electrode 2000) from bottom to top.
Although not shown, a hole blocking layer (not shown) may be further included between the light-emitting layer 400 and the electron transport layer 500, and an electron blocking layer (not shown) may be further included between the hole transport layer 300 and the light-emitting layer 400. A cover layer (not shown) may be further provided between the substrate 100 and the anode 1000, and a cover layer (not shown) may be further provided on the cathode 2000.
As the substrate 100 in fig. 1, a substrate used for an organic light-emitting element can be used, and in particular, a transparent glass substrate or a flexible plastic substrate excellent in mechanical strength, thermal stability, transparency, surface smoothness, handling convenience, and water resistance can be used.
The hole injection electrode 1000 is used as an anode for injecting holes into the organic light-emitting element. In order to inject holes, a material having a low work function may be used, and the material may be formed of a transparent material such as Indium Tin Oxide (ITO), Indium Zinc Oxide (IZO), or graphene (graphene).
On the upper part of the above anode electrode, a sputtering method such as a vacuum deposition method, a spin coating method, a casting method, Langmuir-Bloduotta (LB, Langmuir- [ 0113)]Blodgett) method, etc., to deposit a substance for the hole injection layer, thereby forming the hole injection layer 200. When the hole injection layer is formed by the vacuum deposition method, the deposition conditions vary depending on the compound used as the material of the hole injection layer, the desired structure and thermal characteristics of the hole injection layer, and may be usually 50 to 50Deposition temperature of 0 ℃ 10-8To 10-3Vacuum degree of torr (torr) of 0.01 toDeposition rate per second andthe layer thickness range to 5 μm is suitably selected.
Next, on the upper portion of the hole injection layer 200, a hole transport layer 300 can be formed by depositing a hole transport layer material by a vacuum deposition method, a spin coating method, a casting method, a langmuir-blodgetta (LB) method, or the like. In the case of forming the hole transport layer by the above-mentioned vacuum deposition method, the deposition conditions may vary depending on the compound used, but are generally selected within the range of conditions almost the same as those for forming the hole injection layer. The hole transport layer may be one or more, and may be two layers, for example, a1 st hole transport layer and a 2 nd hole transport layer (light emission assisting layer). Any one or more of the 1 st hole transport layer and the 2 nd hole transport layer may include the compound of chemical formula 1 according to the present invention.
Next, a light-emitting layer material may be deposited on the hole transport layer or the light-emitting auxiliary layer by a vacuum deposition method, a spin coating method, a casting method, a langmuir-blodgetta (LB) method, or the like, to form the light-emitting layer 400. When the light-emitting layer is formed by the vacuum deposition method, the deposition conditions may vary depending on the compound used, but are generally selected within the range of conditions almost the same as those for forming the hole injection layer. In addition, as the material of the light-emitting layer, a known compound can be used as a host or a dopant.
In addition, when a phosphorescent dopant is used in the light emitting layer at the same time, a hole blocking material (HBL) may be additionally stacked by a vacuum deposition method or a spin coating method in order to prevent a phenomenon that triplet excitons or holes diffuse into the electron transport layer. The hole-blocking material used in this case is not particularly limited, and may be selected fromAny known substance used as a hole blocking material is used. For example, it is possible to useExamples of the most representative examples of the oxadiazole derivative, the benzotriazole derivative, the phenanthroline derivative, and the hole-blocking material described in Japanese patent application laid-open No. 11-329734(A1) include Balq (bis (8-hydroxy-2-methylquinoline) - (4-phenylphenoxy) aluminum), and phenanthroline compounds (e.g., BCP (bathocuproine) from UDC).
The electron transport layer 500 is formed on the light emitting layer 400 formed as described above, and at this time, the electron transport layer may be formed by a method such as a vacuum deposition method, a spin coating method, a casting method, or the like. The deposition conditions of the electron transport layer will vary depending on the compound used, but are generally selected within the range of conditions almost the same as those for the formation of the hole injection layer.
Next, the electron injection layer 600 may be formed by depositing an electron injection layer material on the electron transport layer 500, and at this time, the electron injection layer may be formed by a method such as a vacuum deposition method, a spin coating method, a casting method, etc. using a general electron injection layer material.
The compound according to the present invention or a known substance may be used for the hole injection layer 200, the hole transport layer 300, the light-emitting layer 400, and the electron transport layer 500 of the above-described element, or a compound according to the present invention and a known substance may be used together.
Above the electron injection layer 600, the cathode 2000 may be formed by a method such as a vacuum deposition method or a spin coating method. As the cathode, various metals can be used. As specific examples, substances such as aluminum, gold, silver, and the like are included.
As the organic light-emitting element according to the present invention, not only an organic light-emitting element including an anode, a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, an electron injection layer, and a cathode, but also an organic light-emitting element having various structures can be used, and 1 or 2 intermediate layers can be additionally formed as necessary.
The thickness of each organic layer formed by the present invention as described above can be adjusted to a desired degree, specifically 10 to 1000nm, more specifically 20 to 150 nm.
In addition, the present invention can adjust the thickness of the organic layer in a molecular unit in the organic layer including the compound represented by the above chemical formula 1, and thus has advantages of uniform surface and excellent morphological stability.
Next, the present invention will be described in more detail by way of a synthesis example of a compound according to an embodiment of the present invention and a manufacturing example of an organic light emitting element. The following examples are merely illustrative of the present invention, and the scope of the present invention is not limited to the following examples.
<Intermediate production example 1>Synthesis of Compound IM1
Compound IM1 was synthesized according to the following reaction scheme.
In a round-bottomed flask, 3.4g of (4-tritylphenyl) boronic acid ((4-tritylphenyl) boronic acid), 3.0g of 4-bromo-4'-iodo-1,1' -biphenyl (4-bromo-4 '-iodoo-1, 1' -biphenyl) were dissolved to 100ml of 1, 4-bisIn an alkane (1,4-dioxan) and 13ml of K are added2CO3(2M) and 0.3g of Pd (PPh)3)4After which reflux stirring was carried out. The reaction was confirmed by Thin Layer Chromatography (TLC) and was terminated after addition of water. The organic layer was extracted with MC and recrystallized after filtration under reduced pressure, thereby obtaining 3.0g of intermediate IM1 (yield 65%).
<Intermediate production example 2>Synthesis of Compounds IM2 to IM5
Compounds IM2 to IM5 were synthesized by the same method as IM1 of intermediate production example 1, except that the starting materials were changed as shown in table 1 below.
[ TABLE 1 ]
<Production example 1>Synthesis of Compound 97
In a round-bottomed flask were placed 3.0g of IM1, 2.5g of N,9,9-triphenyl-9H-fluoren-2-amine (N,9, 9-triphenyl-9H-fluoroen-2-amine), 0.8g of t-Buona, 0.2g of Pd2(dba)30.3ml of (t-Bu)3P was dissolved in 90ml of toluene and then stirred under reflux. The reaction was confirmed by Thin Layer Chromatography (TLC) and was terminated after addition of water. The organic layer was extracted with MC and column purification and recrystallization were performed after filtration under reduced pressure, thereby obtaining 3.0g of compound 97 (yield 63%).
m/z：879.39(100.0％)、880.39(74.1％)、881.39(26.9％)、882.40(6.5％)、883.40(1.1％)m/z：803.36(100.0％)、804.36(67.6％)、805.36(22.7％)、806.37(4.9％)
<Production example 2>Synthesis of Compound 121
Compound 121 was synthesized by the same method as in production example 1, except that IM2 was used instead of IM1 (yield 60%).
m/z：879.39(100.0％)、880.39(74.1％)、881.39(26.9％)、882.40(6.5％)、883.40(1.1％)
<Production example 3>Synthesis of Compound 349
Compound 349 was synthesized by the same method as in production example 1, except that IM3 was used instead of IM1 (yield 61%).
m/z：895.36(100.0％)、896.37(73.0％)、897.37(30.0％)、898.37(7.5％)、896.36(5.4％)、897.36(3.6％)、898.36(2.5％)、899.37(1.2％)、899.38(1.1％)
<Production example 4>Synthesis of Compound 373
Compound 373 was synthesized by the same method as in preparation example 1, except that IM4 was used in place of IM1 (yield: 59%).
m/z：895.36(100.0％)、896.37(73.0％)、897.37(30.0％)、898.37(7.5％)、896.36(5.4％)、897.36(3.6％)、898.36(2.5％)、899.37(1.2％)、899.38(1.1％)
<Production example 5>Synthesis of Compound 488
Compound 488 was synthesized in the same manner as in preparation example 1, except that IM5 and 4- (dibenzo [ b, d ] furan-4-yl) -N-phenylaniline (4- (dibenzo [ b, d ] furan-4-yl) -N-phenylaniline) were used instead of IM1 and N,9,9-triphenyl-9H-fluoren-2-amine (N,9, 9-triphenylyl-9H-fluoroen-2-amine) (yield: 66%).
m/z：821.31(100.0％)、822.31(70.3％)、823.32(21.3％)、823.31(6.9％)、824.32(5.7％)、824.31(2.2％)
Manufacture of organic light-emitting element
The compounds used in the organic layer of the organic light-emitting device of the present invention are shown in table 2 below, and the comparative compounds used instead of the compounds produced in the above production examples are shown in table 3 below.
[ TABLE 2 ]
[ TABLE 3 ]
<Example 1>
Coating with distilled waterA glass substrate of Indium Tin Oxide (ITO) thin film of thickness was subjected to ultrasonic cleaning. Ultrasonic washing and drying with solvent such as isopropanol, acetone, methanol, etc. after the distilled water washing is completed, transferring to a plasma cleaning machine, cleaning the substrate with oxygen plasma for 5 min, and depositing on the Indium Tin Oxide (ITO) substrate by using a thermal vacuum evaporator as a hole injection layerHI01 andHATCN of (a) formed by deposition as a hole transport layerHT01, deposited as a luminescence-assisting layerThe compound produced in the above production example 1, followed by deposition formation as a light-emitting layerBH01 of BD 013 percent. Next, as an electron transport layer, is deposited and formedET01 Liq (1:1) followed by depositionLiF, and,And then the above-described element was encapsulated in a glove box (Encapsulation) to produce an organic light-emitting element.
<Example 2>To<Example 5>
The organic light emitting element was manufactured by performing the same manufacturing method as in example 1 above and forming the light emission auxiliary layer by deposition using the compounds manufactured by manufacturing examples 2 to 5, respectively.
<Comparative example 1>To<Comparative example 6>
The organic light-emitting element was manufactured by performing the same manufacturing method as in example 1 above, and depositing and forming the light-emission auxiliary layer by using comparative example 1(ref.1) to comparative example 6(ref.6) shown in table 3 above, respectively.
<Evaluation of organic light-emitting element Performance>
The performance of the organic light emitting devices of the examples and comparative examples was evaluated by measuring the current density and luminance under atmospheric pressure with respect to the applied voltage by applying a voltage to a gishley 2400source measurement unit (kinetey 2400source measurement unit) to inject electrons and holes and measuring the luminance when light is emitted using a Konica Minolta (Konica Minolta) spectroradiometer (CS-2000), and the results are shown in table 4.
[ TABLE 4 ]
Op.V
mA/cm2
Cd/A
QE(％)
CIEx
CIEy
LT95
Example 1
3.4
10
7.7
6.6
0.140
0.110
175
Example 2
3.5
10
7.9
6.9
0.139
0.109
182
Example 3
3.6
10
7.9
6.9
0.140
0.109
186
Example 4
3.6
10
8.1
7.0
0.140
0.109
190
Example 5
3.6
10
7.7
6.5
0.142
0.110
180
Comparative example 1
3.9
10
6.4
5.3
0.140
0.111
80
Comparative example 2
4.2
10
6.5
5.4
0.141
0.110
90
Comparative example 3
4.1
10
6.0
5.1
0.140
0.110
106
Comparative example 4
3.8
10
6.7
5.6
0.142
0.111
120
Comparative example 5
4.3
10
6.2
5.2
0.140
0.112
95
Comparative example 6
4.0
10
5.6
4.5
0.140
0.112
88
As can be seen from comparison of the examples of the present invention with the comparative examples, the present invention can realize an organic light emitting element with a lower driving voltage, high efficiency, and a long lifetime. This is because the compound of the present invention forms higher Lowest Unoccupied Molecular Orbital (LUMO) and T1 by substituting 3 rings having excellent electron resistance on nitrogen of arylamine and thereby easily realizes electron interception and exciton interception, as compared to comparative examples 1 and 2.
In addition, the compound of the present invention can bond a triarylmethyl group or triarylsilyl group to the nitrogen of the aromatic amine through 3 or more linking groups, as compared to comparative examples 3 to 6, thereby ensuring excellent molecular alignment and faster hall mobility when forming a thin film, and thereby achieving good charge balance in the light emitting layer and suppressing the roll-off phenomenon.