KR102068415B1 - Delayed fluorescence material and organic light emitting device comprising the same - Google Patents

Abstract

The present specification relates to a delayed fluorescent material consisting of Chemical Formula 1 and an organic light emitting device including the same.

Description

Delayed fluorescent material and an organic light emitting device comprising the same {DELAYED FLUORESCENCE MATERIAL AND ORGANIC LIGHT EMITTING DEVICE COMPRISING THE SAME}

This application claims the benefit of the filing date of Korean Patent Application No. 10-2017-0095434 filed with the Korea Intellectual Property Office on July 27, 2017, the entire contents of which are incorporated herein.

The present specification relates to a delayed fluorescent material and an organic light emitting device including the same.

In order to commercialize the organic light emitting device, it is necessary to improve the efficiency of the light emitting material. For this purpose, studies on phosphorescent and delayed fluorescent materials are actively conducted. However, in the case of the phosphorescent material, although the high efficiency can be achieved, there is a problem in that the price of the metal complex required to implement phosphorescence is high and the life is short.

In the case of delayed fluorescent materials, a recent concept of thermally activated delayed fluorescence (TADF) was introduced to introduce a high-efficiency green fluorescent material with high external quantum efficiency. The concept of thermal activation delayed fluorescence (TADF) represents a phenomenon in which the reverse energy transfer from an excitation triplet state to an excitation singlet state by thermal activation leads to fluorescence emission, and since the light emission occurs through the triplet, it generally has a long lifetime. It is called delayed fluorescence because long light emission occurs. Since the delayed fluorescent material can use both fluorescence and phosphorescence emission, it can solve the problem of external quantum efficiency of the existing fluorescent material and can solve the price problem of phosphorescent material in that it does not need to include a metal complex.

Nature, 492, pp 234-238 J. Am. Chem. Soc., 2012, 134 (36), pp 14706-14709

The present specification provides a delayed fluorescent material and an organic light emitting device including the same.

According to an exemplary embodiment of the present specification, there is provided a delayed fluorescent material consisting of a compound represented by the following formula (1).

[Formula 1]

In Chemical Formula 1,

R1 to R14 are the same as or different from each other, and each independently hydrogen; heavy hydrogen; Nitrile group; Nitro group; Hydroxyl group; Carbonyl group; Ester group; Imide group; Amide group; Substituted or unsubstituted alkyl group; A substituted or unsubstituted cycloalkyl group; Substituted or unsubstituted alkoxy group; Substituted or unsubstituted aryloxy group; Substituted or unsubstituted alkyl thioxy group; Substituted or unsubstituted arylthioxy group; Substituted or unsubstituted alkyl sulfoxy group; Substituted or unsubstituted aryl sulfoxy group; Substituted or unsubstituted alkenyl group; Substituted or unsubstituted silyl group; Substituted or unsubstituted boron group; Substituted or unsubstituted amine group; Substituted or unsubstituted aryl phosphine group; Substituted or unsubstituted phosphine oxide group; Substituted or unsubstituted aryl group; Or a substituted or unsubstituted heteroaryl group.

Further, according to one embodiment of the present specification, the first electrode; A second electrode provided to face the first electrode; And at least one organic material layer provided between the first electrode and the second electrode, wherein at least one of the organic material layers includes the delayed fluorescent material.

An organic light emitting device using a delayed fluorescent material made of a compound represented by Formula 1 according to an exemplary embodiment of the present specification may improve efficiency, low driving voltage, and / or lifespan characteristics.

1 illustrates an organic light emitting device 10 according to an exemplary embodiment of the present specification.
2 is a diagram showing NMR data of Compound 1 according to an exemplary embodiment of the present specification.
3 is a UV-vis absorption spectrum, a photoluminescence spectrum in a solid state and a photoluminescence spectrum in a low-temperature state of Compound 1 according to one embodiment of the present specification.
4 is a cyclic voltammetry graph of Compound 1 according to one embodiment of the present specification.
5 is a diagram showing NMR data of Compound 2 according to an exemplary embodiment of the present specification.
6 is a UV-vis absorption spectrum, a photoluminescence spectrum in a solid state and a photoluminescence spectrum in a low-temperature state of Compound 2 according to one embodiment of the present specification.
7 is a cyclic voltammetry graph of compound 2 according to an exemplary embodiment of the present specification.

According to an exemplary embodiment of the present specification, there is provided a delayed fluorescent material consisting of the compound represented by the formula (1).

The compound represented by Chemical Formula 1 according to an exemplary embodiment of the present specification has a cyano group and a triazine group acting as an electron acceptor to facilitate electron injection, and an organic light emitting device including the delayed fluorescent material has high efficiency and long lifespan. Has

In addition, the compound represented by Formula 1 introduces a phenylene group in which a cyano group is substituted between a triazine group and a carbazole group as a linker, thereby improving battery injection characteristics and thus improving the efficiency of the device. Can be.

According to an exemplary embodiment of the present specification, when the cyano group of Formula 1 is located closer to the biscarbazole side acting as the electron donor (Donor) than the triazine group acting as the electron acceptor (Acceptor), represented by the formula (1) When a delayed fluorescent material made of a compound is applied to an organic light emitting device, there is an effect of improving the life of the device.

Herein delayed fluorescence is meant that the exciton emits fluorescent light in the triplet excited state (T ₁₎ the singlet excited state (S ₁₎ conversion (converting) to be a singlet excited state (S ₁₎ from. Delayed fluorescence is distinguished from fluorescence in that the peak position of the emission spectrum is the same as the fluorescence but the decay time is long, and the peak position of the emission spectrum is the same as the difference between the phosphorescence spectrum and S ₁ -T ₁ energy. It is distinguished from phosphorescence in that it is different.

In the present specification, when a part "includes" a certain component, this means that it may further include other components, without excluding other components, unless specifically stated otherwise.

Examples of substituents in the present specification are described below, but are not limited thereto.

The term "substituted" means that a hydrogen atom bonded to a carbon atom of the compound is replaced with another substituent, and the position to be substituted is not limited to a position where the hydrogen atom is substituted, that is, a position where a substituent can be substituted, if two or more substituted , Two or more substituents may be the same or different from each other.

As used herein, the term "substituted or unsubstituted" is deuterium; Halogen group; Nitrile group; Nitro group; Imide group; Amide group; Carbonyl group; Ester group; Hydroxyl group; Substituted or unsubstituted alkyl group; A substituted or unsubstituted cycloalkyl group; Substituted or unsubstituted alkoxy group; Substituted or unsubstituted aryloxy group; Substituted or unsubstituted alkyl thioxy group; Substituted or unsubstituted arylthioxy group; Substituted or unsubstituted alkyl sulfoxy group; Substituted or unsubstituted aryl sulfoxy group; Substituted or unsubstituted alkenyl group; Substituted or unsubstituted silyl group; Substituted or unsubstituted boron group; Substituted or unsubstituted amine group; Substituted or unsubstituted aryl phosphine group; Substituted or unsubstituted phosphine oxide group; Substituted or unsubstituted aryl group; And it is substituted with one or two or more substituents selected from the group consisting of a substituted or unsubstituted heterocyclic group, or two or more of the substituents exemplified above are substituted with a substituent, or means that do not have any substituents. For example, "a substituent to which two or more substituents are linked" may be a biphenyl group. That is, the biphenyl group may be an aryl group or may be interpreted as a substituent to which two phenyl groups are linked.

In the present specification, the halogen group may be fluorine, chlorine, bromine or iodine.

In this specification, although carbon number of an imide group is not specifically limited, It is preferable that it is C1-C30. Specifically, it may be a compound having a structure as follows, but is not limited thereto.

In the present specification, the amide group may be substituted with nitrogen of the amide group is hydrogen, a linear, branched or cyclic alkyl group having 1 to 30 carbon atoms or an aryl group having 6 to 30 carbon atoms. Specifically, it may be a compound of the following structural formula, but is not limited thereto.

Although carbon number of a carbonyl group in this specification is not specifically limited, It is preferable that it is C1-C30. Specifically, it may be a compound having a structure as follows, but is not limited thereto.

In the present specification, the oxygen of the ester group may be substituted with a linear, branched or cyclic alkyl group having 1 to 25 carbon atoms or an aryl group having 6 to 30 carbon atoms. Specifically, it may be a compound of the following structural formula, but is not limited thereto.

In the present specification, the alkyl group may be linear or branched chain, carbon number is not particularly limited, but is preferably 1 to 30. Specific examples 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-dimethyl Heptyl, 1-ethyl-propyl, 1,1-dimethyl-propyl, isohexyl, 2-methylpentyl, 4-methylhexyl, 5-methylhexyl, and the like, but is not limited thereto.

In the present specification, the cycloalkyl group is not particularly limited, but preferably 3 to 30 carbon atoms, specifically, 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, and the like, but are not limited thereto. It is not.

In the present specification, the alkoxy group may be linear, branched or cyclic. Although carbon number of an alkoxy group is not specifically limited, It is preferable that it is C1-C30. Specifically, methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, tert-butoxy, sec-butoxy, n-pentyloxy, neopentyloxy, isopentyloxy, n -Hexyloxy, 3,3-dimethylbutyloxy, 2-ethylbutyloxy, n-octyloxy, n-nonyloxy, n-decyloxy, benzyloxy, p-methylbenzyloxy, and the like, but It is not limited.

In the present specification, the amine group is -NH ₂ ; Alkylamine group; N-alkylarylamine group; Arylamine group; N-aryl heteroaryl amine group; It may be selected from the group consisting of an N-alkylheteroarylamine group and a heteroarylamine group, and carbon number is not particularly limited, but is preferably 1 to 30. Specific examples of the amine group include methylamine group, dimethylamine group, ethylamine group, diethylamine group, phenylamine group, naphthylamine group, biphenylamine group, anthracenylamine group, and 9-methyl-anthracenylamine group. A diphenylamine group, an N-phenylnaphthylamine group, a tolylamine group, an N-phenyltolylamine group, a triphenylamine group, and an N-phenylbiphenylamine group; N-phenylnaphthylamine group; N-biphenyl naphthylamine group; N-naphthylfluorenylamine group; N-phenylphenanthrenylamine group; N-biphenylphenanthrenylamine group; N-phenylfluorenylamine group; N-phenylterphenylamine group; N-phenanthrenyl fluorenyl amine group; N-biphenyl fluorenyl amine group and the like, but is not limited thereto.

In the present specification, the N-alkylarylamine group means an amine group in which an alkyl group and an aryl group are substituted for N of the amine group.

In the present specification, the N-arylheteroarylamine group means an amine group in which an aryl group and a heteroaryl group are substituted for N in the amine group.

In the present specification, the N-alkylheteroarylamine group means an amine group in which an alkyl group and a heteroaryl group are substituted for N of the amine group.

In the present specification, the alkyl group in the alkylamine group, the N-arylalkylamine group, the alkylthioxy group, the alkyl sulfoxy group, and the N-alkylheteroarylamine group is the same as the example of the alkyl group described above. Specifically, alkyl thioxy groups include methyl thioxy group, ethyl thioxy group, tert-butyl thioxy group, hexyl thioxy group and octyl thioxy group, and the alkyl sulfoxy group includes mesyl, ethyl sulfoxy group, propyl sulfoxy group and butyl sulfoxy group. Etc., but is not limited thereto.

In the present specification, the alkenyl group may be linear or branched chain, carbon number is not particularly limited, but is preferably 2 to 30. Specific examples include vinyl, 1-propenyl, isopropenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-pentenyl, 2-pentenyl, 3-pentenyl, 3-methyl-1- Butenyl, 1,3-butadienyl, allyl, 1-phenylvinyl-1-yl, 2-phenylvinyl-1-yl, 2,2-diphenylvinyl-1-yl, 2-phenyl-2- ( Naphthyl-1-yl) vinyl-1-yl, 2,2-bis (diphenyl-1-yl) vinyl-1-yl, stilbenyl group, styrenyl group and the like, but are not limited thereto.

In the present specification, specifically, the silyl group includes trimethylsilyl group, triethylsilyl group, t-butyldimethylsilyl group, vinyldimethylsilyl group, propyldimethylsilyl group, triphenylsilyl group, diphenylsilyl group, phenylsilyl group, and the like. However, the present invention is not limited thereto.

In the present specification, the boron group may be -BR ₁₀₀ R ₁₀₁ , wherein R ₁₀₀ and R ₁₀₁ are the same as or different from each other, and each independently hydrogen; heavy hydrogen; halogen; Nitrile group; A substituted or unsubstituted monocyclic or polycyclic cycloalkyl group having 3 to 30 carbon atoms; A substituted or unsubstituted linear or branched alkyl group having 1 to 30 carbon atoms; Substituted or unsubstituted monocyclic or polycyclic aryl group having 6 to 30 carbon atoms; And it may be selected from the group consisting of a substituted or unsubstituted monocyclic or polycyclic heteroaryl group having 2 to 30 carbon atoms.

In the present specification, the phosphine oxide group specifically includes a diphenylphosphine oxide group, dinaphthylphosphine oxide, and the like, but is not limited thereto.

In the present specification, the aryl group is not particularly limited, but preferably has 6 to 30 carbon atoms, and the aryl group may be monocyclic or polycyclic.

When the aryl group is a monocyclic aryl group, carbon number is not particularly limited, but is preferably 6 to 30 carbon atoms. Specifically, the monocyclic aryl group may be a phenyl group, a biphenyl group, a terphenyl group, etc., but is not limited thereto.

Carbon number is not particularly limited when the aryl group is a polycyclic aryl group. It is preferable that it is C10-30. Specifically, the polycyclic aryl group may be a naphthyl group, anthracenyl group, phenanthryl group, triphenyl group, pyrenyl group, penalenyl group, peryllenyl group, chrysenyl group, fluorenyl group, fluoranthenyl group, etc. It is not limited to this.

In the present specification, the fluorenyl group may be substituted, and adjacent groups may combine with each other to form a ring.

,

,

,

,

및

등이 될 수 있다. 다만, 이에 한정되는 것은 아니다.When the fluorenyl group is substituted,

,

,

,

,

And

And so on. However, the present invention is not limited thereto.

In the present specification, the term "adjacent" means a substituent substituted on an atom directly connected to the atom to which the corresponding substituent is substituted, a substituent positioned closest to the substituent, or another substituent substituted on the atom to which the substituent is substituted. Can be. For example, two substituents substituted at the ortho position in the benzene ring and two substituents substituted at the same carbon in the aliphatic ring may be interpreted as "adjacent" groups.

In the present specification, the aryl group in the aryloxy group, arylthioxy group, aryl sulfoxy group, N-arylalkylamine group, N-arylheteroarylamine group, and arylphosphine group is the same as the examples of the aryl group described above. Specifically, as the aryloxy group, phenoxy group, p-tolyloxy group, m- toryloxy group, 3,5-dimethyl-phenoxy group, 2,4,6-trimethylphenoxy group, p-tert-butylphenoxy group, 3- Biphenyloxy group, 4-biphenyloxy group, 1-naphthyloxy group, 2-naphthyloxy group, 4-methyl-1- naphthyloxy group, 5-methyl-2- naphthyloxy group, 1- anthryloxy group , 2-anthryloxy group, 9-anthryloxy group, 1-phenanthryloxy group, 3-phenanthryloxy group, 9-phenanthryloxy group, and the like. Examples of the arylthioxy group include a phenylthioxy group and 2- The methylphenyl thioxy group, 4-tert- butylphenyl thioxy group, etc. are mentioned, An aryl sulfoxy group includes a benzene sulfoxy group, p-toluene sulfoxy group, etc., but is not limited to this.

In the present specification, examples of the arylamine group include a substituted or unsubstituted monoarylamine group, or a substituted or unsubstituted diarylamine group. The aryl group in the arylamine group may be a monocyclic aryl group, may be a polycyclic aryl group. The arylamine group including two or more aryl groups may simultaneously include a monocyclic aryl group, a polycyclic aryl group, or a monocyclic aryl group and a polycyclic aryl group. For example, the aryl group in the arylamine group may be selected from the examples of the aryl group described above.

In the present specification, the heteroaryl group includes one or more atoms other than carbon and heteroatoms, and specifically, the heteroatoms may include one or more atoms selected from the group consisting of O, N, Se, and S, and the like. Although carbon number is not particularly limited, it is preferably 2 to 30 carbon atoms, the heteroaryl group may be monocyclic or polycyclic. Examples of the heterocyclic group include thiophene group, furanyl group, pyrrole group, imidazolyl group, thiazolyl group, oxazolyl group, oxadiazolyl group, pyridyl group, bipyridyl group, pyrimidyl group, triazinyl group, tria Zolyl group, acridil group, pyridazinyl group, pyrazinyl group, quinolyl group, quinazolyl group, quinoxalyl group, phthalazinyl group, pyrido pyrimidyl group, pyrido pyrazinyl group, pyrazino pyrazinyl group , Isoquinolyl group, indolyl group, carbazolyl group, benzoxazolyl group, benzimidazolyl group, benzothiazolyl group, benzocarbazolyl group, benzothiophene group, dibenzothiophene group, benzofuranyl group, pe Nanthrolinyl group (phenanthroline), isoxazolyl group, thiadiazolyl group, phenothiazinyl group and dibenzofuranyl group and the like, but is not limited thereto.

In the present specification, examples of the heteroarylamine group include a substituted or unsubstituted monoheteroarylamine group, or a substituted or unsubstituted diheteroarylamine group. The heteroarylamine group including two or more heteroaryl groups may include a monocyclic heteroaryl group, a polycyclic heteroaryl group, or a monocyclic heteroaryl group and a polycyclic heteroaryl group at the same time. For example, the heteroaryl group in the heteroarylamine group may be selected from the examples of the heteroaryl group described above.

In the present specification, examples of the heteroaryl group in the N-arylheteroarylamine group and the N-alkylheteroarylamine group are the same as the examples of the heteroaryl group described above.

According to the exemplary embodiment of the present specification, the compound represented by Chemical Formula 1 simultaneously has biscarbazole, which acts as an electron acceptor such as a triazine group and an electron donor, respectively, in the compound, and these substituents may be By introducing into the position, it is possible to appropriately control the energy difference between the singlet and triplet states of the overall compound. Through this, the thermally activated delayed fluorescent light (TADF) may be represented.

According to an exemplary embodiment of the present specification, the triplet energy level of the compound represented by Formula 1 is 2.0 eV or more, specifically 2.0 eV or more and 3 eV or less, and more specifically, 2.4 eV or more and 2.9 eV or less. to be. When the triplet energy level satisfies the above range, an organic light emitting diode having a low driving voltage, a long lifespan, and excellent luminous efficiency may be implemented.

According to one embodiment of the present specification, the difference between the singlet energy level and triplet energy level of the compound represented by Formula 1 is 0.3 eV or less, specifically 0.25 eV or less, 0.01 eV or more, and even more. Specifically, it is 0.2 eV or less and 0.05 eV or more. The difference between the singlet energy level and the triplet energy level means the absolute value of the singlet energy level and the triplet energy level. When the difference between the singlet energy level and the triplet energy level satisfies the above range, the intramolecular orbital overlap is effectively blocked to prevent the singlet and triplet from overlapping, and thus very low. It may have the difference value. As a result, the interphase transition from the triplet excited state to the singlet excited state through thermal activity is possible even at room temperature, thereby exhibiting delayed fluorescence.

The triplet energy level and singlet energy level may be measured using a method known in the art, but is not limited thereto.

According to an exemplary embodiment of the present specification, Chemical Formula 1 is represented by any one of the following Chemical Formulas 1-1 to 1-3.

[Formula 1-1]

[Formula 1-2]

[Formula 1-3]

In Chemical Formulas 1-1 to 1-3, R1 to R14 are the same as defined in Chemical Formula 1.

According to an exemplary embodiment of the present specification, in the general formula 1, R1 to R14 is hydrogen.

According to an exemplary embodiment of the present specification, Chemical Formula 1 is represented by any one of the following Chemical Formulas 1-4 to 1-6.

[Formula 1-4]

[Formula 1-5]

[Formula 1-6]

According to an exemplary embodiment of the present specification, Formula 1 is selected from the following compounds.

According to an exemplary embodiment of the present specification, an organic light emitting device including a delayed fluorescent material made of a compound represented by Chemical Formula 1 is provided.

According to an exemplary embodiment of the present specification, the first electrode; A second electrode provided to face the first electrode; And at least one organic material layer provided between the first electrode and the second electrode, wherein at least one of the organic material layers includes the above-described delayed fluorescent material.

In this specification, when a member is located "on" another member, this includes not only when one member is in contact with another member but also when another member exists between the two members.

According to an exemplary embodiment of the present specification, the organic material layer of the organic light emitting device of the present specification may be formed of a single layer structure, but may be formed of a multilayer structure in which two or more organic material layers are stacked. For example, the organic light emitting device of the present invention may have a structure including a hole injection layer, a hole transport layer, an electron blocking layer, a light emitting layer, a hole blocking layer, an electron transport layer, an electron injection layer and the like as an organic material layer. However, the structure of the organic light emitting device is not limited thereto and may include fewer or more organic layers.

For example, the structure of the organic light emitting device of the present specification may have a structure as shown in FIG. 1, but is not limited thereto.

1 illustrates a structure of an organic light emitting device 10 in which a first electrode 30, a light emitting layer 40, and a second electrode 50 are sequentially stacked on a substrate 20. 1 is an exemplary structure of an organic light emitting diode according to an exemplary embodiment of the present specification, and may further include another organic material layer.

According to an exemplary embodiment of the present specification, the organic material layer includes a light emitting layer, and the light emitting layer includes the above-described delayed fluorescent material.

According to an exemplary embodiment of the present specification, the organic material layer includes a light emitting layer, and the light emitting layer includes the above-described delayed fluorescent material as a dopant of the light emitting layer.

According to the exemplary embodiment of the present specification, the light emitting material of the light emitting layer is a material capable of emitting light in the visible light region by transporting and combining holes and electrons from the hole transporting layer and the electron transporting layer, respectively, wherein the light emitting layer is the delayed fluorescent material described above. As a dopant of the light emitting layer, at least one of the singlet excitation energy and the excitation triplet energy has a higher value than the light emitting material of the delayed fluorescent material described above, has a hole transporting ability, an electron transporting ability, and has a long wavelength of light emission. It is possible to prevent oxidation and to include an organic compound having a high glass transition temperature as a host.

According to an exemplary embodiment of the present specification, the organic material layer includes a light emitting layer, and the light emitting layer includes a dopant and a host in a weight ratio of 1:99 to 40:60.

According to an exemplary embodiment of the present specification, the organic material layer includes a light emitting layer, and the light emitting layer includes a dopant including the delayed fluorescent material described above and a host in a weight ratio of 1:99 to 40:60.

The organic light emitting device of the present specification may be manufactured by materials and methods known in the art except that the light emitting layer includes a delayed fluorescent material of the present specification, that is, a delayed fluorescent material made of the compound represented by Chemical Formula 1 above. have.

When the organic light emitting device includes a plurality of organic material layers, the organic material layers may be formed of the same material or different materials.

For example, the organic light emitting device of the present specification may be manufactured by sequentially stacking a first electrode, an organic material layer, and a second electrode on a substrate. At this time, by using a physical vapor deposition (PVD: physical vapor deposition) such as sputtering (e-beam evaporation), by depositing a metal or conductive metal oxide or alloys thereof on the substrate It can be prepared by forming a first electrode, forming an organic material layer including a hole injection layer, a hole transport layer, a light emitting layer and an electron transport layer thereon, and then depositing a material that can be used as a second electrode thereon. In addition to the above method, an organic light emitting device may be manufactured by sequentially depositing a second electrode material, an organic material layer, and a first electrode material on a substrate. In addition, the heterocyclic compound represented by Chemical Formula 1 may be formed as an organic material layer by a solution coating method as well as a vacuum deposition method in the manufacture of the organic light emitting device. Here, the solution coating method means spin coating, dip coating, doctor blading, inkjet printing, screen printing, spray method, roll coating, etc., but is not limited thereto.

According to one embodiment of the present specification, the first electrode is an anode, and the second electrode is a cathode.

According to another exemplary embodiment of the present specification, the first electrode is a cathode, and the second electrode is an anode.

As the anode material, a material having a large work function is generally preferred to facilitate hole injection into the organic material layer. Specific examples of the positive electrode material that can be used in the present invention include metals such as vanadium, chromium, copper, zinc, gold or alloys thereof; Metal oxides such as zinc oxide, indium oxide, indium tin oxide (ITO), indium zinc oxide (IZO); ZnO: Al or SnO ₂ : Combination of metals and oxides such as Sb; Conductive polymers such as poly (3-methylthiophene), poly [3,4- (ethylene-1,2-dioxy) thiophene] (PEDOT), polypyrrole and polyaniline, and the like, but are not limited thereto.

It is preferable that the cathode material is a material having a small work function to facilitate electron injection into the organic material layer. Specific examples of the negative electrode 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 LiO ₂ / Al, Mg / Ag, and the like, but are not limited thereto.

The hole injection layer is a layer for injecting holes from the electrode, and has a capability of transporting holes to the hole injection material, and has a hole injection effect at the anode, an excellent hole injection effect to the light emitting layer or the light emitting material, and is produced in the light emitting layer The compound which prevents the excitons from moving to the electron injection layer or the electron injection material, and is excellent in thin film formation ability is preferable. Preferably, the highest occupied molecular orbital (HOMO) of the hole injection material is between the work function of the positive electrode material and the HOMO of the surrounding organic material layer. Specific examples of the hole injection material include metal porphyrin, oligothiophene, arylamine-based organic matter, hexanitrile hexaazatriphenylene-based organic matter, quinacridone-based organic matter, and perylene-based Organic materials, anthraquinone and polyaniline and polythiophene-based conductive polymers, but are not limited thereto.

The hole transport layer is a layer that receives holes from the hole injection layer and transports holes to the light emitting layer. The hole transport material is a material capable of transporting holes from the anode or the hole injection layer to the light emitting layer. The material is suitable. Specific examples thereof include an arylamine-based organic material, a conductive polymer, and a block copolymer having a conjugated portion and a non-conjugated portion together, but are not limited thereto.

The electron transport layer is a layer that receives electrons from the electron injection layer and transports electrons to the light emitting layer. As an electron transporting material, a material capable of injecting electrons well from the cathode and transferring the electrons to the light emitting layer is suitable. Do. Specific examples thereof include Al complexes of 8-hydroxyquinoline; Complexes including Alq ₃ ; Organic radical compounds; Hydroxyflavone-metal complexes and the like, but are not limited thereto. The electron transport layer can be used with any desired cathode material as used according to the prior art. In particular, examples of suitable cathode materials are conventional materials having a low work function followed by an aluminum or silver layer. Specifically cesium, barium, calcium, ytterbium and samarium, followed by aluminum layers or silver layers in each case.

The electron injection layer is a layer that injects electrons from an electrode, has an ability of transporting electrons, has an electron injection effect from a cathode, an electron injection effect with respect to a light emitting layer or a light emitting material, and hole injection of excitons generated in the light emitting layer. The compound which prevents the movement to a layer and is excellent in thin film formation ability is preferable. Specifically, fluorenone, anthraquinodimethane, diphenoquinone, thiopyran dioxide, oxazole, oxadiazole, triazole, imidazole, perylenetetracarboxylic acid, preorenylidene methane, anthrone and the derivatives thereof, metal Complex compounds, nitrogen-containing five-membered ring derivatives, and the like, but are not limited thereto.

Examples of the metal complex compound include 8-hydroxyquinolinato lithium, bis (8-hydroxyquinolinato) zinc, bis (8-hydroxyquinolinato) copper, bis (8-hydroxyquinolinato) manganese, Tris (8-hydroxyquinolinato) aluminum, tris (2-methyl-8-hydroxyquinolinato) aluminum, tris (8-hydroxyquinolinato) gallium, bis (10-hydroxybenzo [h] Quinolinato) beryllium, bis (10-hydroxybenzo [h] quinolinato) zinc, bis (2-methyl-8-quinolinato) chlorogallium, bis (2-methyl-8-quinolinato) ( o-cresolato) gallium, bis (2-methyl-8-quinolinato) (1-naphtholato) aluminum, bis (2-methyl-8-quinolinato) (2-naphtolato) gallium, etc. It is not limited to this.

The organic light emitting device according to the present specification may be a top emission type, a bottom emission type, or a double-sided emission type according to a material used.

According to an exemplary embodiment of the present specification, the delayed fluorescent material may be included in an organic solar cell or an organic transistor in addition to the organic light emitting device.

Hereinafter, the present invention will be described in detail with reference to Examples. However, embodiments according to the present disclosure may be modified in various other forms, and the scope of the present specification is not interpreted to be limited to the embodiments described below. The embodiments of the present specification are provided to more fully describe the present specification to those skilled in the art.

Preparation Example 1 Preparation of Compound 1

1) Preparation of Intermediate 1-1

5-bromo-2-fluorobenzonitrile (10g, 50.27mmol) and Bis (pinacolato) diboron (15.32g, 60.32mmol), [1,1'-Bis (diphenylphosphino) ferrocene] dichloropalladium (II) (1.46g, 2.01mmol ) And potassium acetate (9.87g, 100.54mmol) was dissolved in 100ml of dimethylformamide and stirred while raising the temperature to reflux. After refluxing, the reaction was completed after 12 hours to lower the temperature to room temperature, concentrated under reduced pressure, and purified by column to prepare 9.81 g of intermediate 1-1.

MS [M + H] ⁺ = 248

2) Preparation of Intermediate 1-2

The intermediate 1-1 (9.81g, 39.70mmol) and 2-chloro-4,6-diphenyl-1,3,5-triazine (10.6g, 39.70mmol) and Tetrakis (triphenylphosphine) palladium (0) (0.46g, 0.40 mmol) was added to 60 ml of Tetrahydrofuran, mixed with an aqueous solution of potassium carbonate (16.46 g, 119.1 mmol), and the temperature was increased until reflux. After refluxing, the reaction was terminated after 6 hours to lower the temperature to room temperature, concentrated under reduced pressure, and purified by column to prepare 17.26 g of intermediate 1-2.

MS [M + H] ⁺ = 353

3) Preparation of Compound 1

Intermediate 1-2 (17.26g, 49.02mmol), 9-phenyl-9H, 9'H-3,3'-bicarbazole (20.0g, 49.02mmol) and cesium carbonate (47.91g, 147.06mmol) in 120ml of Dimethylformamide The temperature was raised and stirred under reflux conditions. After 5 hours, the reaction was completed, the temperature was lowered to room temperature, concentrated under reduced pressure, and purified by column to obtain 27.94 g (yield 77%) of Compound 1.

MS [M + H] ⁺ = 741

Physical properties of Compound 1 prepared according to Preparation Example 1 are as follows.

Figure 2 is a diagram showing the NMR data of the compound 1, the NMR data was measured using the Unity Inova of Varian Technology.

FIG. 3 is a UV-vis absorption spectrum, a photoluminescence spectrum in a solid state, and a photoluminescence spectrum in a low-temperature state of Compound 1 according to one embodiment of the present specification, and the UV-vis absorption spectrum is manufactured by JASCO Corporation. Measured using V-730, the absorption spectrum was 200nm to 800nm, HPLC grade THF was used as a solvent, the compound 1 content was 1Х10 ^-5 M. Photoluminescence spectra in the solid state were measured using LS-55 of Perkin Elmer, the emission spectrum at excitation wavelength of 370nm is 400nm to 660nm, HPLC grade THF was used as a solvent, and the content of Compound 1 was 1Х10 ^-5 M. Photoluminescence spectra at low temperature (Temperature) was measured using LS-55 of Perkin Elmer, emission spectrum at excitation wavelength of 360nm is 400nm to 700nm, HPLC grade THF was used as a solvent. The content of compound 1 is 1Х10 ^-5 M and measured under liquid nitrogen.

In FIG. 2, the peak emission wavelength in the solid state is 488 nm, and the peak emission wavelength in the low-temperature state is 499 nm.

Physical properties of the compound 1 measured in Figure 2 are shown in Table 1 below.

UV edge (nm) UV gap
(eV) Fluorescent PL (nm) Phosphorescent PL (nm) Onset Max Onset Max Compound 1 438 2.83 430 488 446 499 Singlet energy (eV) Triplet energy (eV) S1-T1
(onset) Onset Max Onset Max 2.88 2.54 2.78 2.48 0.10

4 is a cyclic voltammetry graph of Compound 1 according to one embodiment of the present specification. The data was measured using Iviumstat from Ivium Tech, and HPLC grade MC was used as the solvent. The ionization potential, electron affinity and bandgap of Compound 1 obtained by the cyclic voltammetry are shown in Table 2 below.

Ionization potential (eV) Electron affinity (eV) Bandgap (CV) Compound 1 -5.81 -3.44 2.37

Preparation Example 2 Preparation of Compound 2

1) Preparation of Intermediate 2-1

9.07g of Intermediate 2, except that 2-bromo-5-fluorobenzonitrile (10g, 50.27mmol) was used instead of 5-bromo-2-fluorobenzonitrile in Preparation of Intermediate 1-1 of Preparation Example 1 -1 was prepared.

MS [M + H] ⁺ = 248

2) Preparation of Intermediate 2-2

Except for using the intermediate 2-1 (9.07, 36.70mmol) instead of the intermediate 1-1 in the preparation of 2) intermediate 1-2 of Preparation Example 1 to prepare a 10.21g of intermediate 2-2 It was.

MS [M + H] ⁺ = 353

3) Preparation of Compound 2

16.62g (yield 76%) of Compound 2, except that Intermediate 2-2 (10.21g, 28.99mmol) was used instead of Intermediate 1-2 in the preparation of Compound 1 of 3). Was prepared.

MS [M + H] ⁺ = 741

The physical properties of Compound 2 prepared according to Preparation Example 2 are as follows.

5 is a diagram showing an NMR data of the compound 2, the NMR data was measured by using the Unity Inova of Varian Technology.

FIG. 6 is a UV-vis absorption spectrum, a photoluminescence spectrum in a solid state, and a photoluminescence spectrum in a low-temperature state of Compound 2 according to one embodiment of the present specification, and the UV-vis absorption spectrum is manufactured by JASCO Corporation. It was measured using V-730, the absorption spectrum was 200nm to 800nm, HPLC grade THF was used as a solvent, and the content of Compound 2 was 1Х10 ^-5 M. The photoluminescence spectrum in the solid state was measured using LS-55 of Perkin Elmer, the emission spectrum at the excitation wavelength of 390nm is 420nm to 750nm, HPLC grade THF was used as the solvent, and the content of Compound 2 was 1Х10 ^-5 M. Photoluminescence spectra at low temperature (Temperature) were measured using LS-55 of Perkin Elmer, emission spectrum at 350 nm excitation wavelength is 400nm to 670nm, HPLC grade THF was used as a solvent. The content of compound 2 is 1Х10 ^-5 M and measured under liquid nitrogen.

In FIG. 6, the peak emission wavelength in the solid state is 465 nm, and the peak emission wavelength in the low-temperature state is 483 nm.

Physical properties of the compound 2 measured in Figure 6 are shown in Table 3.

UV edge (nm) UV gap
(eV) Fluorescent PL (nm) Phosphorescent PL (nm) Onset Max Onset Max Compound 2 417 2.97 413 465 435 483 Singlet energy (eV) Triplet energy (eV) S1-T1
(onset) Onset Max Onset Max 3.00 2.66 2.85 2.56 0.15

5 is a cyclic voltammetry graph of Compound 2 according to an exemplary embodiment of the present specification. The data was measured using Iviumstat from Ivium Tech, and HPLC grade MC was used as the solvent. The ionization potential, electron affinity, and band gap of Compound 2 obtained by the cyclic voltammetry are shown in Table 4 below.

Ionization potential (eV) Electron affinity (eV) Bandgap (CV) Compound 2 -5.76 -3.47 2.29

Preparation Example 3 Preparation of Compound 6

1) Preparation of Intermediate 3-1

9.31g of Intermediate 3 was prepared in the same manner as in Preparation 1, Intermediate 1-1, except that 3-bromo-2-fluorobenzonitrile (10g, 50.27mmol) was used instead of 5-bromo-2-fluorobenzonitrile. -1 was prepared.

MS [M + H] ⁺ = 248

2) Preparation of Intermediate 3-2

Except for using the intermediate 3-1 (9.31, 37.67mmol) instead of the intermediate 1-1 in the preparation of 2) intermediate 1-2 of Preparation Example 1 to prepare a 10.53g of intermediate 3-2 It was.

MS [M + H] ⁺ = 353

3) Preparation of Compound 6

Preparation of 3) Compound 1 of 17.05g (yield 77%) of Compound 6 was prepared in the same manner except that Intermediate 3-2 (10.53g, 29.91mmol) was used instead of Intermediate 1-2 in the preparation of Compound 1. Was prepared.

MS [M + H] ⁺ = 741

Example 1-1

A glass substrate coated with a thin film of ITO (indium tin oxide) at a thickness of 1,000 Å was placed in distilled water in which detergent was dissolved and ultrasonically cleaned. At this time, Fischer Co. product was used as a detergent, and distilled water filtered secondly as a filter of Millipore Co. product was used as distilled water. After ITO was washed for 30 minutes, ultrasonic washing was performed twice with distilled water for 10 minutes. After washing the distilled water, ultrasonic washing with a solvent of isopropyl alcohol, acetone, methanol, dried and transported to a plasma cleaner. In addition, the substrate was cleaned for 5 minutes using an oxygen plasma, and then the substrate was transferred to a vacuum evaporator.

Thus prepared N1, N1 '-([1,1'-biphenyl] -4,4'-diyl) bis (N1-phenyl-N4, N4-di-m-tolylbenzene-1,4-diamine on the prepared ITO transparent electrode ) [DNTPD] was thermally vacuum deposited to a thickness of 600 kPa to form a hole injection layer. N4, N4, N4 ', N4'-tetra ([1,1'-biphenyl] -4-yl)-[1,1'-biphenyl] -4,4'-diamine [BPBPA] on the hole injection layer 50 Å and 9,9-dimethyl-10- (9-phenyl-9H-carbazol-3-yl) -9,10-dihydroacridine [PCZAC] 600 하기 were sequentially vacuum deposited to form a hole transport layer. Subsequently, 9- (3 '-(4,6-diphenyl-1,3,5-triazin-2-yl)-[1,1'-biphenyl] -3-yl) having a thickness of 200 kPa on the hole transport layer. -9H-carbazole [DCz] and the compound 1 were vacuum-deposited at a weight ratio of 100: 3 to form a light emitting layer.

2,8-bis (4,6-diphenyl-1,3,5-triazin-2-yl) dibenzo [b, d] furan [DBFTrz] and 2- (4- (9,10-) Di (naphthalen-2-yl) anthracen-2-yl) phenyl) -1-phenyl-1H-benzo [d] imidazole [ZADN] was sequentially formed to an electron transport layer having a thickness of 350 kHz. Lithium fluoride (LiF) and aluminum were deposited to a thickness of 1,000 Å on the electron transport layer in order to form an electron injection layer and a cathode.

In the above process, the deposition rate of the organic material was maintained at 0.4 to 0.9 Å / sec, the lithium fluoride of the cathode was maintained at 0.3 Å / sec, and the aluminum was maintained at a deposition rate of 2 Å / sec. ^An organic light-emitting device was manufactured by maintaining ^-7 to 5 Х 10 ^-8 torr.

Example 1-2

An organic light-emitting device was manufactured in the same manner as in Experimental Example 1-1, except that DCz and Compound 1 were vacuum deposited in a 20: 1 weight ratio in Experimental Example 1-1.

Example 1-3

The organic light emitting device was manufactured by the same method as Experimental Example 1-1, except that DCz and Compound 1 were vacuum deposited in 10: 1 weight ratio in Experimental Example 1-1.

Example 1-4

An organic light-emitting device was manufactured in the same manner as in Experimental Example 1-1, except that DCz and Compound 1 were vacuum deposited in a 5: 1 weight ratio in Experimental Example 1-1.

Example 1-5

The organic light emitting device was manufactured by the same method as Experimental Example 1-1, except that compound 2 was used instead of compound 1 in Experimental Example 1-1.

Example 1-6

An organic light-emitting device was manufactured in the same manner as in Experimental Example 1-5, except that DCz and Compound 2 were vacuum deposited in a 20: 1 weight ratio in Experimental Example 1-5.

Example 1-7

The organic light emitting device was manufactured by the same method as Experimental Example 1-5, except that DCz and Compound 2 were vacuum-deposited at a weight ratio of 10: 1 in Experimental Example 1-5.

Example 1-8

An organic light-emitting device was manufactured in the same manner as in Example 1-5, except that DCz and Compound 2 were vacuum deposited in a 5: 1 weight ratio in Experimental Example 1-5.

[Example 1-9]

The organic light emitting device was manufactured by the same method as Experimental Example 1-1, except that compound 6 was used instead of compound 1 in Experimental Example 1-1.

Comparative Example 1-1

An organic light emitting diode was manufactured according to the same method as Experimental Example 1-4 except for using the following D1 instead of compound 1 in Experimental Example 1-4.

Comparative Example 1-2

An organic light emitting diode was manufactured according to the same method as Experimental Example 1-4 except for using the following D2 instead of compound 1 in Experimental Example 1-4.

Comparative Example 1-3

An organic light emitting diode was manufactured according to the same method as Experimental Example 1-4 except for using the following D3 instead of compound 1 in Experimental Example 1-4.

The organic light emitting diodes manufactured in Examples 1-1 to 1-9 and Comparative Examples 1-1 to 1-3 were used to fabricate a current-voltage-luminance using a Photo Research PR-655 IVL meter. IVL), color coordinates (CIE), quantum efficiency (QE), luminous efficiency (LE), and current efficiency (J) were measured, and the results are shown in Tables 5 and 6 below.

Voltage
(V) Current density
(A / Cm ² ) Luminance
(cd / m ² ) Color coordinates (CIE) x y Example 1-1 6.5 2.3 1000.4 0.24 0.5 Example 1-2 6.2 2.1 998.7 0.25 0.51 Example 1-3 6.2 1.9 994.9 0.26 0.53 Example 1-4 5.8 2 1007.2 0.29 0.56 Example 1-5 6.7 2.2 1000 0.23 0.51 Example 1-6 6.6 2 999.7 0.23 0.52 Example 1-7 6.4 2 995.8 0.25 0.52 Example 1-8 6.3 2.1 1003.4 0.26 0.53 Example 1-9 6.5 2.2 999.1 0.25 0.54 Comparative Example 1-1 7.1 1.7 995.8 0.33 0.6 Comparative Example 1-2 7.3 1.6 997.9 0.3 0.55 Comparative Example 1-3 7.3 1.7 1000.4 0.29 0.59

Quantum Efficiency (%) Luminous Efficiency (lm / W) Current efficiency (Cd / A) 1000cd max. 1000cd max. 1000cd max. Example 1-1 17.2 21.4 21.4 28.1 44.4 48.8 Example 1-2 18.6 25 25 32.5 49.1 53.3 Example 1-3 19 26.5 26.5 33.7 51.9 55.4 Example 1-4 17.4 28.3 28.3 35 51.7 53 Example 1-5 16.8 21.1 22.8 27.4 45 48.7 Example 1-6 17.7 23 25.7 30.8 48.7 50.4 Example 1-7 18.3 22.7 26.6 32.9 51.1 52.4 Example 1-8 18 23 27.7 34.1 50.7 54.1 Example 1-9 17.6 22.8 23.7 29.1 45.7 55.9 Comparative Example 1-1 17 17.1 21.2 23.3 40.1 43.7 Comparative Example 1-2 16.1 16.9 20.4 25.4 43 47.8 Comparative Example 1-3 15.8 16 19.1 22.6 41.4 44

Examples 1-1 to 1-9, which are organic light emitting devices including Formula 1 according to one embodiment of the present specification as a delayed fluorescent material, as shown in Tables 5 and 6, are triphenylene and biscarbazole, in which CN is phenylene. The organic light emitting device including the same has a lower driving voltage, a lower current density, and higher luminance than Comparative Examples 1-1 to 1-3, which are organic light emitting devices including the compounds of D1 to D3. This is excellent in quantum efficiency, luminous efficiency and current efficiency.

10: organic light emitting device
20: substrate
30: first electrode
40: light emitting layer
50: second electrode

Claims (8)

Delayed fluorescent material consisting of a compound represented by the formula
[Formula 1]

In Chemical Formula 1,
R1 to R14 are the same as or different from each other, and each independently hydrogen; heavy hydrogen; Nitrile group; Nitro group; Hydroxyl group; Carbonyl group; Ester group; Imide group; Amide group; Substituted or unsubstituted alkyl group; A substituted or unsubstituted cycloalkyl group; Substituted or unsubstituted alkoxy group; Substituted or unsubstituted aryloxy group; Substituted or unsubstituted alkyl thioxy group; Substituted or unsubstituted arylthioxy group; Substituted or unsubstituted alkyl sulfoxy group; Substituted or unsubstituted aryl sulfoxy group; Substituted or unsubstituted alkenyl group; Substituted or unsubstituted silyl group; Substituted or unsubstituted boron group; Substituted or unsubstituted amine group; Substituted or unsubstituted aryl phosphine group; Substituted or unsubstituted phosphine oxide group; Substituted or unsubstituted aryl group; Or a substituted or unsubstituted heteroaryl group. The delayed fluorescent material of claim 1, wherein the triplet energy level of the compound represented by Chemical Formula 1 is 2.0 eV or more. The delayed fluorescent material of claim 1, wherein a difference between the singlet energy level and the triplet energy level of the compound represented by Chemical Formula 1 is 0.3 eV or less. The method of claim 1, wherein Formula 1 is a delayed fluorescent material represented by any one of the following Formulas 1-1 to 1-3:
[Formula 1-1]

[Formula 1-2]

[Formula 1-3]

In Chemical Formulas 1-1 to 1-3,
R1 to R14 are the same as defined in the formula (1). The delayed fluorescent material of claim 1, wherein Formula 1 is selected from the following compounds:

A first electrode; A second electrode provided to face the first electrode; And at least one organic material layer provided between the first electrode and the second electrode, wherein at least one of the organic material layers includes the delayed fluorescent material of any one of claims 1 to 5. device. The organic light emitting device of claim 6, wherein the organic material layer comprises a light emitting layer, and the light emitting layer comprises the delayed fluorescent material. The organic light emitting device of claim 6, wherein the organic material layer includes a light emitting layer, and the light emitting layer includes the delayed fluorescent material as a dopant of the light emitting layer.

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