KR20210096445A - Organic light emitting device - Google Patents

Abstract

The present invention provides an organic light emitting element, wherein the organic light emitting element comprises: a positive pole; a hole transport layer; a light emitting layer; an electron transport layer; and a negative pole. Therefore, the present invention is capable of improving a lifespan characteristic.

Description

Organic light emitting device

The present invention relates to an organic light emitting device.

In general, the organic light emitting phenomenon refers to a phenomenon in which electric energy is converted into light energy using an organic material. The organic light emitting device using the organic light emitting phenomenon has a wide viewing angle, excellent contrast, fast response time, and excellent luminance, driving voltage, and response speed characteristics, and thus many studies are being conducted.

An organic light emitting device generally has a structure including an anode and a cathode and an organic material layer between the anode and the cathode. The organic layer is often formed of a multi-layered structure composed of different materials in order to increase the efficiency and stability of the organic light-emitting device, and may include, for example, a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer, and the like. In the structure of the organic light emitting device, when a voltage is applied between the two electrodes, holes are injected into the organic material layer from the anode and electrons from the cathode are injected into the organic material layer. When the injected holes and electrons meet, excitons are formed, and the excitons When it falls back to the ground state, it lights up.

The development of new materials for organic materials used in organic light emitting devices as described above is continuously required.

Meanwhile, in order to reduce process costs, an organic light emitting diode using a solution process, particularly an inkjet process, has been developed instead of a conventional deposition process. In the early days, it was attempted to develop an organic light emitting device by coating all organic light emitting device layers with a solution process, but current technology has limitations. A hybrid process using

Korean Patent Publication No. 10-2000-0051826

The present invention relates to an organic light emitting device.

The present invention provides the following organic light emitting device:

anode;

hole transport layer;

light emitting layer;

electron transport layer; and

including a cathode;

The light emitting layer includes a compound represented by the following formula (1),

The electron transport layer comprises a compound represented by the following formula (2),

Organic light emitting device:

[Formula 1]

In Formula 1,

L ₁ and L ₂ are each independently a single bond; or C _6-12 arylene;

L ₃ is a single bond; Or a substituted or unsubstituted C _6-60 arylene,

R ₁ and R ₂ are each independently, substituted or unsubstituted C _1-60 alkyl; or substituted or unsubstituted C _3-60 cycloalkyl,

R ₃ and R ₄ are each independently hydrogen; heavy hydrogen; substituted or unsubstituted C _1-60 alkyl; Or a substituted or unsubstituted C _6-60 aryl,

n and m are each independently an integer of 0 to 4,

Ar is substituted or unsubstituted C _6-60 aryl; _{Or substituted or unsubstituted C 2-60} heteroaryl comprising any one or more selected from the group consisting of N, O and S,

[Formula 2]

In Formula 2,

A' is each independently a benzene ring, a naphthalene ring, or a pyridine ring fused to an adjacent ring,

One of R' is a substituent represented by the following formula (3), and the rest are each independently hydrogen; heavy hydrogen; halogen; nitrile; nitro; amino; substituted or unsubstituted C _1-60 alkyl; substituted or unsubstituted C _3-60 cycloalkyl; a substituted or unsubstituted C _2-60 alkenyl group; substituted or unsubstituted C _6-60 aryl; _{or C 2-60} heteroaryl comprising at least one of substituted or unsubstituted O, N, Si and S,

[Formula 3]

In Formula 3,

L' is a single bond; substituted or unsubstituted C _6-60 arylene; _{Or C 2-60} heteroarylene comprising at least one of substituted or unsubstituted O, N, Si and S,

X' is O, S, or Se;

을 형성한다.Ar' ₁ and Ar' ₂ are each independently, substituted or unsubstituted C _6-60 aryl; _{or C 2-60} heteroaryl containing at least one of substituted or unsubstituted O, N, Si and S, or P to which _{Ar′ 1} , Ar′ ₂ , and Ar′ ₁ and Ar′ _{2 are bonded} with

to form

The above-described organic light emitting device may improve efficiency, low driving voltage, and/or lifespan characteristics in the organic light emitting device by adjusting the compounds included in the light emitting layer and the electron transport layer.

FIG. 1 shows an example of an organic light emitting device including a substrate 1 , an anode 2 , a hole transport layer 3 , a light emitting layer 4 , an electron transport layer 5 , and a cathode 6 .
2 shows a substrate 1, an anode 2, a hole injection layer 7, a hole transport layer 3, a light emitting layer 4, an electron transport layer 5, an electron injection layer 8 and a cathode 6 An example of an organic light emitting device is shown.

Hereinafter, it will be described in more detail to help the understanding of the present invention.

, 또는

는 다른 치환기에 연결되는 결합을 의미한다. In this specification,

, or

means a bond connected to another substituent.

As used herein, the term "substituted or unsubstituted" refers to deuterium; halogen group; nitrile group; nitro group; hydroxyl group; carbonyl group; ester group; imid; amino group; phosphine oxide group; alkoxy group; aryloxy group; alkyl thiooxy group; arylthioxy group; an alkyl sulfoxy group; arylsulfoxy group; silyl group; boron group; an alkyl group; cycloalkyl group; alkenyl group; aryl group; aralkyl group; aralkenyl group; an alkylaryl group; an alkylamine group; an aralkylamine group; heteroarylamine group; arylamine group; an arylphosphine group; or N, O, and S atom means that it is substituted or unsubstituted with one or more substituents selected from the group consisting of a heterocyclic group containing one or more atoms, or substituted or unsubstituted with two or more substituents connected among the above-exemplified substituents . For example, "a substituent in which two or more substituents are connected" may be a biphenyl group. That is, the biphenyl group may be an aryl group, and may be interpreted as a substituent in which two phenyl groups are connected.

In the present specification, the number of carbon atoms in the carbonyl group is not particularly limited, but preferably 1 to 40 carbon atoms. Specifically, it may be a compound having the following structure, but is not limited thereto.

In the present specification, in the ester group, 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 25 carbon atoms. Specifically, it may be a compound of the following structural formula, but is not limited thereto.

In the present specification, the number of carbon atoms of the imide group is not particularly limited, but it is preferably from 1 to 25 carbon atoms. Specifically, it may be a compound having the following structure, but is not limited thereto.

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

In the present specification, the boron group specifically includes, but is not limited to, a trimethylboron group, a triethylboron group, a t-butyldimethylboron group, a triphenylboron group, a phenylboron group, and the like.

In the present specification, examples of the halogen group include fluorine, chlorine, bromine or iodine.

In the present specification, the alkyl group may be linear or branched, and the number of carbon atoms is not particularly limited, but is preferably 1 to 40. According to an exemplary embodiment, the number of carbon atoms in the alkyl group is 1 to 20. According to another exemplary embodiment, the alkyl group has 1 to 10 carbon atoms. According to another exemplary embodiment, the alkyl group has 1 to 6 carbon atoms. Specific examples of the alkyl group include methyl, ethyl, propyl, n-propyl, isopropyl, butyl, n-butyl, isobutyl, tert-butyl, sec-butyl, 1-methyl-butyl, 1-ethyl-butyl, pentyl, n -pentyl, isopentyl, neopentyl, tert-pentyl, hexyl, n-hexyl, 1-methylpentyl, 2-methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl, 2-ethylbutyl, heptyl , n-heptyl, 1-methylhexyl, cyclopentylmethyl, cyclohexylmethyl, octyl, n-octyl, tert-octyl, 1-methylheptyl, 2-ethylhexyl, 2-propylpentyl, n-nonyl, 2,2 -Dimethylheptyl, 1-ethyl-propyl, 1,1-dimethyl-propyl, isohexyl, 2-methylpentyl, 4-methylhexyl, 5-methylhexyl and the like, but are not limited thereto.

In the present specification, the alkenyl group may be linear or branched, and the number of carbon atoms is not particularly limited, but is preferably 2 to 40. According to an exemplary embodiment, the carbon number of the alkenyl group is 2 to 20. According to another exemplary embodiment, the carbon number of the alkenyl group is 2 to 10. According to another exemplary embodiment, the alkenyl group has 2 to 6 carbon atoms. 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, the cycloalkyl group is not particularly limited, but preferably has 3 to 60 carbon atoms, and according to an exemplary embodiment, the cycloalkyl group has 3 to 30 carbon atoms. According to another exemplary embodiment, the carbon number of the cycloalkyl group is 3 to 20. According to another exemplary embodiment, the cycloalkyl group has 3 to 6 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 is not limited thereto.

In the present specification, the aryl group is not particularly limited, but preferably has 6 to 60 carbon atoms, and may be a monocyclic aryl group or a polycyclic aryl group. According to an exemplary embodiment, the carbon number of the aryl group is 6 to 30. According to an exemplary embodiment, the carbon number of the aryl group is 6 to 20. The aryl group may be a monocyclic aryl group such as a phenyl group, a biphenyl group, or a terphenyl group, but is not limited thereto. The polycyclic aryl group may be a naphthyl group, an anthracenyl group, a phenanthryl group, a pyrenyl group, a perylenyl group, a chrysenyl group, a fluorenyl group, and the like, but is not limited thereto.

등이 될 수 있다. 다만, 이에 한정되는 것은 아니다.In the present specification, the fluorenyl group may be substituted, and two substituents may be bonded to each other to form a spiro structure. When the fluorenyl group is substituted,

etc. can be However, the present invention is not limited thereto.

In the present specification, the heterocyclic group is a heterocyclic group including at least one of O, N, Si and S as a heterogeneous element, and the number of carbon atoms is not particularly limited, but it is preferably from 2 to 60 carbon atoms. Examples of the heterocyclic group include a thiophene group, a furan group, a pyrrole group, an imidazole group, a thiazole group, an oxazole group, an oxadiazole group, a triazole group, a pyridyl group, a bipyridyl group, a pyrimidyl group, a triazine group, an acridyl group , pyridazine group, pyrazinyl group, quinolinyl group, quinazoline group, quinoxalinyl group, phthalazinyl group, pyrido pyrimidinyl group, pyrido pyrazinyl group, pyrazino pyrazinyl group, isoquinoline group, indole group , carbazole group, benzoxazole group, benzoimidazole group, benzothiazole group, benzocarbazole group, benzothiophene group, dibenzothiophene group, benzofuranyl group, phenanthroline group, isoxazolyl group, thiadia and a jolyl group, a phenothiazinyl group, and a dibenzofuranyl group, but is not limited thereto.

In the present specification, the aryl group in the aralkyl group, the aralkenyl group, the alkylaryl group, and the arylamine group is the same as the example of the aryl group described above. In the present specification, the alkyl group among the aralkyl group, the alkylaryl group, and the alkylamine group is the same as the example of the above-described alkyl group. In the present specification, as for heteroaryl among heteroarylamines, the description of the above-described heterocyclic group may be applied. In the present specification, the alkenyl group among the aralkenyl groups is the same as the above-described examples of the alkenyl group. In the present specification, the description of the above-described aryl group may be applied except that arylene is a divalent group. In the present specification, the description of the above-described heterocyclic group may be applied, except that heteroarylene is a divalent group. In the present specification, the hydrocarbon ring is not a monovalent group, and the description of the above-described aryl group or cycloalkyl group may be applied, except that it is formed by combining two substituents. In the present specification, the heterocyclic group is not a monovalent group, and the description of the above-described heterocyclic group may be applied, except that it is formed by combining two substituents.

The present invention, the positive electrode; hole transport layer; light emitting layer; electron transport layer; and a cathode, wherein the emission layer includes the compound represented by Formula 1, and the electron transport layer includes the compound represented by Formula 2, and provides an organic light emitting device.

The organic light emitting device according to the present invention can improve efficiency, low driving voltage, and/or lifespan characteristics in the organic light emitting device by controlling the compound included in the emission layer and the compound included in the electron transport layer.

Hereinafter, the present invention will be described in detail for each configuration.

positive and negative

As the anode material, a material having a large work function is generally preferred so that holes can be smoothly injected into the organic material layer. Specific examples of the anode material include metals such as vanadium, chromium, copper, zinc, gold, or alloys thereof; metal oxides such as zinc oxide, indium oxide, indium tin oxide (ITO), and indium zinc oxide (IZO); combinations of metals and oxides such as ZnO:Al or SnO _{2 :Sb;} conductive polymers such as poly(3-methylthiophene), poly[3,4-(ethylene-1,2-dioxy)thiophene](PEDOT), polypyrrole, and polyaniline, but are not limited thereto.

The cathode material is preferably a material having a small work function to facilitate electron injection into the organic material layer. Specific examples of the anode material include metals such as magnesium, calcium, sodium, potassium, titanium, indium, yttrium, lithium, gadolinium, aluminum, silver, tin and lead, or alloys thereof; and a multilayer structure material such as LiF/Al or LiO ₂ /Al, but is not limited thereto.

In addition, a hole injection layer may be additionally included on the anode. The hole injection layer is made of a hole injection material, and the hole injection material has the ability to transport holes, so it has a hole injection effect at the anode, an excellent hole injection effect on the light emitting layer or the light emitting material, and the excitons generated in the light emitting layer A compound which prevents movement to the electron injection layer or the electron injection material and is excellent in the ability to form a thin film is preferred.

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 material, hexanitrile hexaazatriphenylene-based organic material, quinacridone-based organic material, and perylene. organic materials, anthraquinone, polyaniline and polythiophene-based conductive polymers, and the like, but are not limited thereto.

hole injection layer

The organic light emitting diode according to the present invention may include a hole injection layer between the anode and the hole transport layer, if necessary.

The hole injection layer is a layer for injecting holes from the electrode, and as a hole injection material, it has the ability to transport holes, so it has a hole injection effect at the anode, an excellent hole injection effect with respect to the light emitting layer or the light emitting material, and is produced in the light emitting layer A compound which prevents the movement of excitons to the electron injection layer or the electron injection material and is excellent in the ability to form a thin film 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 material, hexanitrile hexaazatriphenylene-based organic material, quinacridone-based organic material, and perylene-based organic material. of organic substances, anthraquinones, polyaniline and polythiophene-based conductive polymers, and the like, but are not limited thereto.

hole transport layer

The hole transport layer used in the present invention is a layer that receives holes from the hole injection layer formed on the anode or the anode and transports them to the light emitting layer. As a material with high hole mobility, it is suitable. Specific examples include, but are not limited to, an arylamine-based organic material, a conductive polymer, and a block copolymer having a conjugated portion and a non-conjugated portion together.

light emitting layer

The light emitting material included in the light emitting layer is a material capable of emitting light in the visible ray region by transporting and combining holes and electrons from the hole transport layer and the electron transport layer, respectively, and a material having good quantum efficiency for fluorescence or phosphorescence is preferable. The emission layer may include a host material and a dopant material. In particular, in the present invention, the compound represented by Formula 1 is used as the host material.

The compound represented by Formula 1 has high solubility in a solvent used for a solution process due to an alkyl group or a cycloalkyl group in fluorene, and has high molecular weight and glass transition temperature, so that it has excellent processability.

Preferably, Chemical Formula 1 is represented by the following Chemical Formula 1-1 or 1-2:

[Formula 1-1]

[Formula 1-2]

In Formulas 1-1 and 1-2,

L ₁ to L ₃ , R ₁ to R ₄ , n, m, and Ar are as defined in claim 1.

Preferably, L ₁ and L ₂ are phenylene or biphenyldiyl, more preferably 1,4-phenylene or biphenyl-4,4'-diyl.

Preferably, L ₃ is a single bond; or phenylene, more preferably a single bond; or 1,3-phenylene.

Preferably, R ₁ and R ₂ are each independently C _1-10 alkyl, more preferably R ₁ and R ₂ are methyl, ethyl, propyl, butyl, isobutyl, tertbutyl, pentyl, isopentyl, neopentyl, or hexyl.

Preferably, n and m are zero.

Preferably, Ar is phenyl, biphenyl, or naphthyl.

Representative examples of the compound represented by Formula 1 are as follows, and C ₆ H ₁₃ in the following means straight-chain hexyl.

The compound represented by Chemical Formula 1 may be prepared by a preparation method as shown in Scheme 1 below.

[Scheme 1]

In Scheme 1, the rest except for X are as defined above, and X is halogen, preferably bromo or chloro. The reaction is a Suzuki coupling reaction, and is preferably performed in the presence of a palladium catalyst and a base, and the reactor for the Suzuki coupling reaction can be changed as known in the art. The manufacturing method may be more specific in Preparation Examples to be described later.

Meanwhile, examples of the dopant material include an aromatic amine derivative, a strylamine compound, a boron complex, a fluoranthene compound, and a metal complex. Specifically, the aromatic amine derivative is a condensed aromatic ring derivative having a substituted or unsubstituted arylamino group, and includes pyrene, anthracene, chrysene, and periflanthene having an arylamino group, and the styrylamine compound is a substituted or unsubstituted derivative. It is a compound in which at least one arylvinyl group is substituted in the arylamine, and one or two or more substituents selected from the group consisting of an aryl group, a silyl group, an alkyl group, a cycloalkyl group and an arylamino group are substituted or unsubstituted. Specifically, there are styrylamine, styryldiamine, styryltriamine, styryltetraamine, and the like, but is not limited thereto. In addition, the metal complex includes, but is not limited to, an iridium complex, a platinum complex, and the like.

Meanwhile, the compound represented by Formula 1 may form a light emitting layer by a solution process. To this end, the present invention provides a coating composition comprising the compound represented by Formula 1 and a solvent.

The solvent is not particularly limited as long as it is a solvent capable of dissolving or dispersing the compound represented by Formula 1, and for example, chloroform, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, chlorobenzene , chlorine-based solvents such as o-dichlorobenzene; ether solvents such as tetrahydrofuran and dioxane; aromatic hydrocarbon solvents such as toluene, xylene, trimethylbenzene, and mesitylene; aliphatic hydrocarbon solvents such as cyclohexane, methylcyclohexane, n-pentane, n-hexane, n-heptane, n-octane, n-nonane, and n-decane; ketone solvents such as acetone, methyl ethyl ketone, and cyclohexanone; ester solvents such as ethyl acetate, butyl acetate, and ethyl cellosolve acetate; Polyvalents such as ethylene glycol, ethylene glycol monobutyl ether, ethylene glycol monoethyl ether, ethylene glycol monomethyl ether, dimethoxyethane, propylene glycol, diethoxymethane, triethylene glycol monoethyl ether, glycerin, and 1,2-hexanediol alcohols and derivatives thereof; alcohol solvents such as methanol, ethanol, propanol, isopropanol and cyclohexanol; sulfoxide solvents such as dimethyl sulfoxide; and amide solvents such as N-methyl-2-pyrrolidone and N,N-dimethylformamide; benzoate solvents such as butyl benzoate and methyl-2-methoxy benzoate; tetralin; and solvents such as 3-phenoxytoluene. In addition, the above-mentioned solvents may be used alone or as a mixture of two or more solvents. Preferably, toluene may be used as the solvent.

In addition, the coating composition may further include a compound used as the dopant material described above.

In addition, the viscosity of the coating composition is preferably 1 cP to 10 cP, and coating is easy in the above range. In addition, the concentration of the compound represented by Formula 1 in the coating composition is preferably 0.1 wt/v% to 20 wt/v%.

Preferably, the solubility (wt%) in the solvent of the coating composition is 1.0 to 10.0, more preferably 2.5 to 10.0, based on the solvent toluene, and thus the coating composition comprising the compound represented by Formula 1 is Suitable for use in solution processes.

In addition, the present invention provides a method of forming a light emitting layer using the above-described coating composition. Specifically, the step of coating the light emitting layer according to the present invention on the anode or on the hole transport layer formed on the anode in a solution process; and heat-treating the coated coating composition.

The solution process uses the coating composition according to the present invention described above, and refers to spin coating, dip coating, doctor blading, inkjet printing, screen printing, spraying, roll coating, and the like, but is not limited thereto.

The heat treatment temperature in the heat treatment step is preferably 150 to 230 ℃. In addition, the heat treatment time is 1 minute to 3 hours, more preferably 10 minutes to 1 hour. In addition, the heat treatment is preferably performed in an inert gas atmosphere such as argon or nitrogen.

electron transport layer

The electron transport layer is a layer that receives electrons from the electron injection layer and transports electrons to the light emitting layer. use a compound that is

In Formula 2, preferably, all of A' are benzene rings; one of A' is a pyridine ring and the other is a benzene ring; one of A' is a naphthalene ring and the other is a benzene ring; or two of A' are naphthalene rings, and the other is a benzene ring.

Preferably, L' is phenylene, biphenylrylene, naphthylene, phenanthrenylene, anthracenylene, pyridinylene, quinolinylene, or isoquinolinylene.

을 형성한다. Preferably, Ar′ ₁ and Ar′ ₂ are each independently phenyl, biphenylyl, or naphthyl; or together with P to which Ar′ ₁ , Ar′ ₂ , and Ar′ ₁ and Ar′ _{2 are bonded.}

to form

Representative examples of the compound represented by Formula 2 are as follows:

In addition, a compound having the following structure among the compounds represented by Formula 2 may be prepared in the same manner as in Scheme 2, and the remaining compounds may be prepared in a similar manner.

[Scheme 2]

In Scheme 2, definitions other than X" are the same as defined above, and X" is halogen and more preferably bromo or chloro.

The reaction is a Suzuki coupling reaction, and is preferably performed in the presence of a palladium catalyst and a base, and the reactor for the Suzuki coupling reaction can be changed as known in the art. The manufacturing method may be more specific in Preparation Examples to be described later.

electron injection layer

The organic light emitting diode according to the present invention may include an electron injection layer between the electron transport layer and the cathode, if necessary.

The electron injection layer is a layer that injects electrons from the electrode, has the ability to transport electrons, has an electron injection effect from the cathode, an excellent electron injection effect on the light emitting layer or the light emitting material, and hole injection of excitons generated in the light emitting layer. A compound which prevents movement to a layer and is excellent in the ability to form a thin film is preferable. Specifically, fluorenone, anthraquinodimethane, diphenoquinone, thiopyran dioxide, oxazole, oxadiazole, triazole, imidazole, perylenetetracarboxylic acid, preorenylidene methane, anthrone, etc., derivatives thereof, metals complex compounds and nitrogen-containing 5-membered ring derivatives, 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-crezolato)gallium, bis(2-methyl-8-quinolinato)(1-naphtolato)aluminum, bis(2-methyl-8-quinolinato)(2-naphtolato)gallium, etc. However, the present invention is not limited thereto.

organic light emitting device

The structure of the organic light emitting device according to the present invention is illustrated in FIG. 1 . FIG. 1 shows an example of an organic light emitting device including a substrate 1 , an anode 2 , a hole transport layer 3 , a light emitting layer 4 , an electron transport layer 5 , and a cathode 6 . In such a structure, the compound represented by Formula 1 may be included in the emission layer, and the compound represented by Formula 2 may be included in the electron transport layer.

2 shows a substrate 1, an anode 2, a hole injection layer 7, a hole transport layer 3, a light emitting layer 4, an electron transport layer 5, an electron injection layer 8 and a cathode 6 An example of an organic light emitting device is shown. In such a structure, the compound represented by Formula 1 may be included in the emission layer, and the compound represented by Formula 2 may be included in the electron transport layer.

The organic light emitting device according to the present invention may be manufactured by sequentially stacking the above-described components. At this time, by using a PVD (physical vapor deposition) method such as sputtering or e-beam evaporation, a metal or conductive metal oxide or an alloy thereof is deposited on a substrate to form an anode. And, after forming each of the above-mentioned layers thereon, it can be prepared by depositing a material that can be used as a cathode thereon. In addition to this method, an organic light emitting device may be manufactured by sequentially depositing a cathode material, an organic material layer, and an anode material on a substrate. In addition, the light emitting layer may be formed by a solution coating method as well as a vacuum deposition method for the host and dopant. Here, the solution coating method refers to spin coating, dip coating, doctor blading, inkjet printing, screen printing, spraying, roll coating, and the like, but is not limited thereto.

In addition to this method, an organic light emitting device may be manufactured by sequentially depositing an organic material layer and an anode material from a cathode material on a substrate (WO 2003/012890). However, the manufacturing method is not limited thereto.

On the other hand, the organic light emitting device according to the present invention may be a top emission type, a back emission type, or a double-sided emission type depending on the material used.

The manufacturing of the organic light emitting device according to the present invention will be described in detail below. However, the following specific content is intended to illustrate the present invention, and the scope of the present invention is not limited thereto.

Preparation 1-1: Preparation of compound 1-1

1) Preparation of intermediate compound A1

1-Bromo-4-(tert-butyl)benzene (13.1 ml, 75.6 mmol) was dissolved in THF (200 ml), 2.5 M n-BuLi (27.5 ml) was slowly added dropwise in a dry ice bath, and stirred for 30 minutes. . Methyl 4'-bromo-[1,1'-biphenyl]-2-carboxylate (10 g, 34.34 mmol) was dissolved in THF (50 ml) and slowly injected, followed by stirring at room temperature for about 5 hours. After quenching the reaction with water, ethyl acetate and water were added to extract the organic layer, moisture was removed with magnesium sulfate, concentrated, and then adsorbed to silica, followed by column chromatography. The material obtained through the column was precipitated in hexane to obtain Intermediate A-1 (6.5 g).

2) Preparation of intermediate compound A2

The obtained intermediate compound A1 (6.53 g, 12.4 mmol) was dissolved in dichloromethane (50 ml), an ice bath was installed, and the temperature was set to 0°C. 48% BF ₃ OEt ₂ (3.6 ml) was slowly added dropwise, the temperature was raised to room temperature, and the mixture was stirred for about 3 hours. The _{reaction was quenched with an aqueous Na 2} CO ₃ solution, and the organic layer was extracted by adding water and dichloromethane. The obtained reactant was diluted in hexane and precipitated in methanol to obtain Intermediate A-2 (about 4.6 g).

3) Preparation of compound 1-1

The obtained intermediate compound A2 (2 g, 3.9 mmol), 4,4,5,5-tetramethyl-2-(4-(10-(naphthalen-1-yl)anthracen-9-yl)phenyl)-1 ,3,2-dioxaborolane (1.82 g, 4.3 mmol), and potassium carbonate (1.62 g, 11.7 mmol) were added to toluene (30 ml), ethanol (5 ml), and water (5 ml), followed by temperature was heated to 90 °C and dissolved. Pd(PPh ₃ ) ₄ (0.23 g, 11.7 mmol) was added and reacted at 90° C. for about 3 hours. The temperature was lowered, the organic layer was extracted with ethyl acetate, moisture was removed with magnesium sulfate, the residual catalyst was adsorbed with charcoal, and filtered through celite and silica. The filtrate was adsorbed on silica and subjected to column chromatography to obtain Compound 1-1 (2.0 g).

MS[M+H] ⁺ = 809.7

Preparation 1-2: Preparation of compound 1-2

Compound 1-2 was prepared in the same manner as in Preparation Example 1-1, except that 4-bromotoluene was used instead of 1-bromo-4-(tert-butyl)benzene in step 1 of Preparation Example 1-1. did.

MS[M+H] ⁺ = 725.32

Preparation Example 1-3: Preparation of compound 1-3

4,4,5,5-tetramethyl-2-(4-(10-(naphthalen-1-yl)anthracen-9-yl)phenyl)-1,3,2- in step 3 of Preparation Example 1-1 4,4,5,5-tetramethyl-2-(3-(10-(naphthalen-1-yl)anthracen-9-yl)phenyl)-1,3,2-dioxaborolane instead of dioxaborolane Except for using the compound 1-3 was prepared in the same manner as in Preparation Example 1-1.

MS[M+H] ⁺ = 809.41

Preparation 2-1: Preparation of compound 2-1

(Preparation of Intermediate 2-1-1)

2,4-dichlorophenylboronic acid (2,4-dichlorophenylboronic acid, 18.3 g, 95.8 mmol) and 1-bromo-2-naphthaldehyde (1-bromo-2-naphthaldehyde, 20.5 g, 87.2 mmol) After it was completely dissolved in tetrahydrofuran (THF, 300 mL), a 2 M aqueous potassium carbonate solution (180 mL) was added, and tetrakistriphenylphosphine palladium (Pd(PPh ₃ ) ₄ , 2.0 g, 2 mol%) was added. The mixture was stirred and refluxed for 5 hours. The temperature was lowered to room temperature, the water layer was removed, and the organic layer was dried over anhydrous magnesium sulfate (MgSO ₄ ) and filtered. The filtrate was concentrated under reduced pressure and columned with tetrahydrofuran:hexane at a volume ratio of 1:10 to prepare the intermediate 2-1-1 (21.0 g, yield: 80%).

MS: [M+H] ⁺ = 301

(Preparation of Intermediate 2-1-2)

Intermediate 2-1-1 (26.2 g, 87.0 mmol) and diaminobenzene (9.4 g, 87.0 mmol) were suspended in dioxane (1,4-dioxane, 200 mL) and acetic acid (AcOH, 20 mL). The resulting mixture was stirred and refluxed for about 6 hours, and then cooled to room temperature. After the mixture was diluted with water (100 mL), the resulting solid was filtered and washed with water and ethyl ether to prepare the intermediate 2-1-2 (19.3 g, yield: 57%). .

MS: [M+H] ⁺ = 389

(Preparation of Intermediate 2-1-3)

Intermediate 2-1-2 (1.99 g, 5.10 mmol) with sodium-tertiary-butoxide (NaO t -Bu, 0.58 g, 6.01 mmol) and Pd[P( t- Bu) ₃ ] ₂ (51 mg, 2 mol%) was suspended in toluene (50 mL). The resulting mixture was stirred and refluxed for about 6 hours, and then cooled to room temperature. Distilled water was added to the reaction solution to terminate the reaction, the organic layer was extracted, dried over anhydrous magnesium sulfate, and then filtered. The filtrate was concentrated under reduced pressure and columned with tetrahydrofuran:hexane at a volume ratio of 1:5 to prepare the intermediate 2-1-3 (0.756 g, yield: 42%).

MS: [M+H] ⁺ = 353

(Preparation of Intermediate 2-1-4)

Intermediate 2-1-3 (12 g, 34 mmol), bis(pinacolato)diboron (12 g, 47 mmol), and potassium acetate (12 g, 118 mmol) were dissolved in dioxane (150 mL), The temperature was raised to 50 °C, Pd(dba) ₂ (0.23 g, 0.4 mmol) and P(Cy) ₃ (0.22 g, 0.8 mmol) were added thereto, followed by heating and stirring for 12 hours. After the reaction solution was cooled to room temperature, distilled water (100 mL) was added thereto, followed by extraction with methylene chloride (100 mL Х 3). The organic layer was concentrated and recrystallized from ethanol to obtain Intermediate 2-1-4 (14 g, yield: 90%).

MS: [M+H] ⁺ = 445

(Preparation of Intermediate 2-1-5)

2,6-dibromonaphthalene (20 g, 69.94 mmol) was dissolved in tetrahydrofuran (100 mL), and then cooled to -78 °C. n- BuLi (2.5 M, 37 ml, 93 mmol) was slowly added dropwise, followed by stirring for 30 minutes. Chlorodiphenylphosphine (17 g, 76 mmol) was slowly added dropwise, stirred for 3 hours, and then raised to room temperature, water (100 mL) was added, and extraction was performed with tetrahydrofuran. The organic layer was concentrated and recrystallized from hexane to obtain Intermediate 2-1-5 (21 g, yield: 76.8 %).

MS: [M+H] ⁺ = 391

(Preparation of Intermediate 2-1-6)

Intermediate 2-5 (20 g, 51 mmol) was dissolved in trichloromethane (200 mL), hydrogen peroxide (20 mL) was added thereto, and the mixture was stirred for 12 hours. MgSO ₄ was added, stirred to remove water, concentrated by filtration, and recrystallized from hexane to obtain an intermediate 2-1-6 (18 g, yield: 86.5 %).

MS: [M+H] ⁺ = 407

(Preparation of compound 2-1)

Intermediate 2-1-4 (9.0 g, 20.3 mmol) and Intermediate 2-1-6 (9.1 g, 22.4 mmol) were completely dissolved by heating in tetrahydrofuran (200 mL), and then 100 mL of 2 M aqueous potassium carbonate solution was added. Then, Pd(PPh ₃ ) ₄ (0.26 g, 0.22 mmol) was added and stirred for 12 hours. After cooling to room temperature, the water layer was removed and the resulting solid was filtered. The filtered solid was recrystallized from tetrahydrofuran and acetone to obtain compound 2-1 (8.5 g, yield: 65%).

MS: [M+H] ⁺ = 645

Preparation 2-2: Preparation of compound 2-2

(Preparation of Intermediate 2-2-1)

2,4-dichlorophenylboronic acid (2,4-dichlorophenylboronic acid, 18.3 g, 95.8 mmol) and 2-bromo-1-naphthaldehyde (1-bromo-2-naphthaldehyde, 20.5 g, 87.2 mmol) After it was completely dissolved in tetrahydrofuran (THF, 300 mL), a 2 M aqueous potassium carbonate solution (180 mL) was added, and tetrakistriphenylphosphine palladium (Pd(PPh ₃ ) ₄ , 2.0 g, 2 mol%) was added. The mixture was stirred and refluxed for 5 hours. The temperature was lowered to room temperature, the water layer was removed, and the organic layer was dried over anhydrous magnesium sulfate (MgSO ₄ ) and filtered. The filtrate was concentrated under reduced pressure and columned with tetrahydrofuran:hexane at a volume ratio of 1:10 to prepare Intermediate 2-2-1 (21.0 g, yield: 80%).

MS: [M+H] ⁺ = 301

(Preparation of Intermediate 2-2-2)

Intermediate 2-2-1 (26.2 g, 87.0 mmol) and diaminobenzene (9.4 g, 87.0 mmol) were suspended in dioxane (1,4-dioxane, 200 mL) and acetic acid (AcOH, 20 mL). The resulting mixture was stirred and refluxed for about 6 hours, and then cooled to room temperature. After the mixture was diluted with water (100 mL), the resulting solid was filtered and washed with water and ethyl ether to prepare the intermediate 2-2-2 (19.3 g, yield: 57%). .

MS: [M+H] ⁺ = 389

(Preparation of Intermediate 2-2-3)

Intermediate 2-2-2 (1.99 g, 5.10 mmol) with sodium-tertiary-butoxide (NaOt-Bu, 0.58 g, 6.01 mmol) and Pd[P( t- Bu) ₃ ] ₂ (51 mg, 2 mol) %) was suspended in toluene (50 mL). The resulting mixture was stirred and refluxed for about 6 hours, and then cooled to room temperature. Distilled water was added to the reaction solution to terminate the reaction, the organic layer was extracted, dried over anhydrous magnesium sulfate, and then filtered. The filtrate was concentrated under reduced pressure and columned with tetrahydrofuran:hexane at a volume ratio of 1:5 to prepare the intermediate 2-2-3 (0.756 g, yield: 42%).

MS: [M+H] ⁺ = 353

(Preparation of Intermediate 2-2-4)

Intermediate 2-2-3 (12 g, 34 mmol), bis (pinacolato) diboron (12 g, 47 mmol) and potassium acetate (12 g, 118 mmol) were dissolved in dioxane (150 mL), The temperature was raised to 50 °C, Pd(dba) ₂ (0.23 g, 0.4 mmol) and P(Cy) ₃ (0.22 g, 0.8 mmol) were added thereto, followed by heating and stirring for 12 hours. After the reaction solution was cooled to room temperature, distilled water (100 mL) was added thereto, followed by extraction with methylene chloride (100 mL × 3). The organic layer was concentrated and recrystallized from ethanol to obtain an intermediate 2-2-4 (14 g, yield: 90 %).

MS: [M+H] ⁺ = 445

(Preparation of Intermediate 2-2-5)

2,7-dibromonaphthalene (20 g, 69.94 mmol) was dissolved in tetrahydrofuran (100 mL), and then cooled to -78 °C. n- BuLi (2.5 M, 37 mL, 93 mmol) was slowly added dropwise, followed by stirring for 30 minutes. Chlorodiphenylphosphine (17 g, 76 mmol) was slowly added dropwise, stirred for 3 hours, and then raised to room temperature, water (100 mL) was added, and extraction was performed with tetrahydrofuran. The organic layer was concentrated and recrystallized from hexane to obtain an intermediate 2-2-5 (21 g, yield: 76.8 %).

MS: [M+H] ⁺ = 391

(Preparation of Intermediate 2-2-6)

Intermediate 2-2-6 was obtained in the same manner as in the preparation method of Intermediate 2-1-6 of Preparation Example 2-1, except that Intermediate 2-2-5 was used instead of Intermediate 2-1-5.

MS: [M+H] ⁺ = 407

(Preparation of compound 2-2)

The same method as for the preparation of compound 2-1 of Preparation Example 2-1, except that Intermediate 2-2-4 was used instead of Intermediate 2-1-4 and Intermediate 2-2-6 was used instead of Intermediate 2-1-6. Compound 2-2 was obtained by the method.

MS: [M+H] ⁺ = 445

Example 1

A glass substrate coated with indium tin oxide (ITO) to a thickness of 1,500 Å was placed in distilled water in which detergent was dissolved and washed with ultrasonic waves. At this time, a product manufactured by Fischer Co. was used as the detergent, and distilled water that was secondarily filtered with a filter manufactured by Millipore Co. was used as the distilled water. After washing ITO for 30 minutes, ultrasonic washing was performed for 10 minutes by repeating twice with distilled water. After washing with distilled water, ultrasonic cleaning was performed with a solvent of isopropyl and acetone and dried. After washing the substrate for 5 minutes, the substrate was transported to a glove box.

On the ITO transparent electrode, a 2wt% cyclohexanone solution of the following compound A and the following p dopant (compound E) (weight ratio of 8:2) was spin-coated on the ITO surface (4000 rpm) and heat treated at 200° C. for 30 minutes to 400 A hole injection layer was formed to a thickness of Å. Then, Compound B was dissolved in toluene at 0.7 wt%, and spin-coated on the hole injection layer to form a film of 200 Å, and heated at 200° C. for 30 minutes under a nitrogen atmosphere to form a hole transport layer. Then, on the hole transport layer, a 0.5 wt% solution of toluene mixed with compound C in a weight ratio of 8% to compound 1-1 prepared above was spin-coated to form a light emitting layer having a thickness of 200 Å. Compound 2-1 prepared above was vacuum-deposited to a thickness of 350 Å on the emission layer to form an electron injection and electron transport layer. A cathode was formed by sequentially depositing LiF to a thickness of 10 Å and aluminum to a thickness of 1000 Å on the electron injection and transport layer.

In the above process, the deposition rate of organic material was maintained at 0.4 to 0.7 Å/sec, the deposition rate of LiF of the cathode was maintained at 0.3 Å/sec, and the deposition rate of aluminum was maintained at 2 Å/sec, and the vacuum degree during deposition was 2×10 ^-7 to 5×10 ⁻⁸ torr were maintained.

Examples 2 and 3

An organic light emitting diode was manufactured in the same manner as in Example 1, except that the compound shown in Table 1 was used instead of Compound 1-1.

Example 4

An organic light emitting device was prepared in the same manner as in Example 1, except that Compound 2-2 was used instead of Compound 2-1.

Comparative Examples 1 and 2

An organic light emitting diode was manufactured in the same manner as in Example 1, except that the compound shown in Table 1 was used instead of Compound 1-1. In Table 1, Comparative Compounds 1 to 2 are as follows, respectively.

Comparative Example 3

An organic light emitting diode was prepared in the same manner as in Example 1, except that Compound D below was used instead of Compound 2-1.

Experimental example

Table 1 shows the results of measuring the driving voltage, current efficiency, and external quantum efficiency of the organic light-emitting devices prepared in Examples and Comparative Examples at ^{a current density of 10 mA/cm 2 .} The external quantum efficiency can be calculated as (number of emitted photons)/(number of injected charge carriers).

EML host ETL drive voltage
(V) current efficiency
(cd/A) EQE
(%) Example 1 compound 1-1 compound 2-1 4.34 3.39 7.16 Example 2 compound 1-2 compound 2-1 4.22 3.84 6.86 Example 3 compound 1-3 compound 2-1 4.24 3.95 7.47 Example 4 compound 1-1 compound 2-2 4.34 3.73 6.57 Comparative Example 1 Comparative compound 1 compound 2-1 4.39 4.29 5.82 Comparative Example 2 Comparative compound 2 compound 2-1 4.38 4.81 5.85 Comparative Example 3 compound 1-1 compound D 4.19 1.15 3.62

1: Substrate 2: Anode
3: hole transport layer 4: light emitting layer
5: electron transport layer 6: cathode
7: hole injection layer 8: electron injection layer

Claims (13)

anode;
hole transport layer;
light emitting layer;
electron transport layer; and
including a cathode;
The light emitting layer includes a compound represented by the following formula (1),
The electron transport layer comprises a compound represented by the following formula (2),
Organic light emitting device:
[Formula 1]

In Formula 1,
L ₁ and L ₂ are each independently a single bond; or C _6-12 arylene;
L ₃ is a single bond; Or a substituted or unsubstituted C _6-60 arylene,
R ₁ and R ₂ are each independently, substituted or unsubstituted C _1-60 alkyl; or substituted or unsubstituted C _3-60 cycloalkyl,
R ₃ and R ₄ are each independently hydrogen; heavy hydrogen; substituted or unsubstituted C _1-60 alkyl; Or a substituted or unsubstituted C _6-60 aryl,
n and m are each independently an integer of 0 to 4,
Ar is substituted or unsubstituted C _6-60 aryl; _{Or substituted or unsubstituted C 2-60} heteroaryl comprising any one or more selected from the group consisting of N, O and S,
[Formula 2]

In Formula 2,
A' is each independently a benzene ring, a naphthalene ring, or a pyridine ring fused to an adjacent ring,
One of R' is a substituent represented by the following formula (3), and the rest are each independently hydrogen; heavy hydrogen; halogen; nitrile; nitro; amino; substituted or unsubstituted C _1-60 alkyl; substituted or unsubstituted C _3-60 cycloalkyl; a substituted or unsubstituted C _2-60 alkenyl group; substituted or unsubstituted C _6-60 aryl; _{or C 2-60} heteroaryl comprising at least one of substituted or unsubstituted O, N, Si and S,
[Formula 3]

In Formula 3,
L' is a single bond; substituted or unsubstituted C _6-60 arylene; _{Or C 2-60} heteroarylene comprising at least one of substituted or unsubstituted O, N, Si and S,
X' is O, S, or Se;
Ar' ₁ and Ar' ₂ are each independently, substituted or unsubstituted C _6-60 aryl; _{or C 2-60} heteroaryl containing at least one of substituted or unsubstituted O, N, Si and S, or P to which _{Ar′ 1} , Ar′ ₂ , and Ar′ ₁ and Ar′ _{2 are bonded} with

to form
According to claim 1,
Formula 1 is represented by the following Formula 1-1, or 1-2,
Organic light emitting device:
[Formula 1-1]

[Formula 1-2]

In Formulas 1-1 and 1-2,
L ₁ to L ₃ , R ₁ to R ₄ , n, m, and Ar are as defined in claim 1.
According to claim 1,
L ₁ and L ₂ are phenylene, or biphenyldiyl;
organic light emitting device.
According to claim 1,
L ₃ is a single bond; or phenylene;
organic light emitting device.
According to claim 1,
R ₁ and R ₂ are each independently C _1-10 alkyl,
organic light emitting device.
According to claim 1,
R ₁ and R ₂ are methyl, ethyl, propyl, butyl, isobutyl, tertbutyl, pentyl, isopentyl, neopentyl, or hexyl;
organic light emitting device.
According to claim 1,
n and m are 0;
organic light emitting device.
According to claim 1,
Ar is phenyl, biphenyl, or naphthyl;
organic light emitting device.
According to claim 1,
The compound represented by Formula 1 is any one selected from the group consisting of
Organic light emitting device:

.
According to claim 1,
A' are all benzene rings;
one of A' is a pyridine ring and the other is a benzene ring;
one of A' is a naphthalene ring and the other is a benzene ring; or
Two of A' are naphthalene rings and the rest are benzene rings,
organic light emitting device.
According to claim 1,
L' is phenylene, biphenylrylene, naphthylene, phenanthrenylene, anthracenylene, pyridinylene, quinolinylene, or isoquinolinylene;
organic light emitting device.
According to claim 1,
Ar′ ₁ and Ar′ ₂ are each independently phenyl, biphenylyl, or naphthyl; or together with P to which Ar′ ₁ , Ar′ ₂ , and Ar′ ₁ and Ar′ _{2 are bonded.}

to form,
organic light emitting device.
According to claim 1,
The compound represented by Formula 2 is any one selected from the group consisting of
Organic light emitting device:

.

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