KR102487980B1 - Novel polymer and organic light emitting device comprising the same - Google Patents

Abstract

The present invention provides a polymer compound and an organic light emitting device using the same.

Description

Novel polymer and organic light emitting device using the same {Novel polymer and organic light emitting device comprising the same}

The present invention relates to a novel polymer and an organic light emitting device including the same.

In general, the organic light emitting phenomenon refers to a phenomenon in which electrical energy is converted into light energy using an organic material. An organic light emitting device using an organic light emitting phenomenon has a wide viewing angle, excellent contrast, and a fast response time, and has 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, a cathode, and an organic material layer between the anode and the cathode. In order to increase the efficiency and stability of the organic light emitting device, the organic material layer is often composed of a multi-layered structure composed of different materials, and may include, for example, a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer. In the structure of this organic light emitting device, when a voltage is applied between the two electrodes, holes are injected from the anode and electrons from the cathode are injected into the organic material layer, and when the injected holes and electrons meet, excitons are formed. When it falls back to the ground state, it glows.

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

Meanwhile, in recent years, an organic light emitting device using a solution process, particularly an inkjet process, instead of a conventional deposition process has been developed to reduce process costs. In the early days, an attempt was made to develop an organic light emitting device by coating all organic light emitting device layers with a solution process, but the current technology has limitations, so only HIL, HTL, and EML in the form of a regular structure are carried out as a solution process, and the subsequent process is the existing deposition process A hybrid process that utilizes is being studied.

Accordingly, the present invention provides a novel material for an organic light emitting device that can be used for an organic light emitting device and can be deposited in a solution process at the same time.

Korean Patent Publication No. 10-2000-0051826

The present invention relates to a novel polymer and an organic light emitting device including the same.

The present invention provides a polymer comprising a repeating unit represented by Formula 1 below:

[Formula 1]

In Formula 1,

n is an integer from 1 to 5;

a and b are each independently an integer from 0 to 4;

L is a single bond; Or a substituent represented by Formula 2 below,

[Formula 2]

R ₁ to R ₄ are each independently hydrogen; heavy hydrogen; halogen; cyano; Substituted or unsubstituted C _1-60 Alkyl; Substituted or unsubstituted C _1-60 alkoxy; Substituted or unsubstituted C _1-60 thioalkyl; Substituted or unsubstituted C _3-60 cycloalkyl; Substituted or unsubstituted C _6-60 aryl; C _5-60 heteroaryl containing one or more heteroatoms selected from the group consisting of substituted or unsubstituted N, O and S; or tri(C _1-60 alkyl)silyl;

Ar ₁ is phenyl substituted with C _1-10 alkyl or C _3-10 cycloalkyl; substituted or unsubstituted C _10-60 aryl; Or a substituted or unsubstituted fluorenyl,

Ar ₂ is a substituted or unsubstituted C _6-60 aryl.

In addition, the present invention is a positive electrode; a cathode provided to face the anode; a light emitting layer provided between the anode and the cathode; and a hole transport layer provided between the anode and the light emitting layer, wherein the hole transport layer includes the polymer.

The polymer according to the present invention can be used as a material for a hole transport layer of an organic light emitting device, can be deposited through a solution process, and can improve efficiency, low driving voltage and/or lifetime characteristics of an organic light emitting device.

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, and a cathode 5.
2 is composed of a substrate (1), an anode (2), a hole injection layer (6), a hole transport layer (3), a light emitting layer (4), an electron transport layer (7), an electron injection layer (8) and a cathode (5). An example of an organic light emitting device is shown.
Figure 3 is a graph evaluating the solvent resistance of the polymer according to an embodiment of the present invention.

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

,

또는

는 다른 치환기에 연결되는 결합을 의미한다. In this specification,

,

or

means a bond connected to another substituent.

In this specification, the term "substituted or unsubstituted" means deuterium; halogen group; nitrile group; nitro group; hydroxy group; carbonyl group; ester group; imide group; amino group; phosphine oxide group; alkoxy group; aryloxy group; Alkyl thioxy group; Arylthioxy group; an alkyl sulfoxy group; aryl sulfoxy groups; silyl group; boron group; an alkyl group; cycloalkyl group; alkenyl group; aryl group; aralkyl group; Aralkenyl group; Alkyl aryl group; Alkylamine group; Aralkylamine group; heteroarylamine group; Arylamine group; Arylphosphine group; Or substituted or unsubstituted with one or more substituents selected from the group consisting of a heterocyclic group containing at least one of N, O, and S atoms, or substituted or unsubstituted with two or more substituents linked to each other among the substituents exemplified above. . 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 of the carbonyl group is not particularly limited, but is 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, the ester group may be substituted with an aryl group having 6 to 25 carbon atoms or a straight-chain, branched-chain or cyclic chain alkyl group having 1 to 25 carbon atoms in the ester group. 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 is preferably 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 is specifically 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. but not limited to

In the present specification, the boron group specifically includes a trimethyl boron group, a triethyl boron group, a t-butyldimethyl boron group, a triphenyl boron group, a phenyl boron group, but is not limited thereto.

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

In the present specification, the alkyl group may be straight-chain or branched-chain, and the number of carbon atoms is not particularly limited, but is preferably 1 to 40. According to one embodiment, the number of carbon atoms of the alkyl group is 1 to 20. According to another exemplary embodiment, the number of carbon atoms of the alkyl group is 1 to 10. 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, etc., but is 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 one embodiment, the alkenyl group has 2 to 20 carbon atoms. According to another exemplary embodiment, the alkenyl group has 2 to 10 carbon atoms. 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, etc., but is 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 number of carbon atoms of the cycloalkyl group is 3 to 20. According to another exemplary embodiment, the number of carbon atoms of the cycloalkyl group is 3 to 6. 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.

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 one embodiment, the number of carbon atoms of the aryl group is 6 to 30. According to one embodiment, the number of carbon atoms of the aryl group is 6 to 20. The aryl group may be a phenyl group, a biphenyl group, a terphenyl group, etc. as a monocyclic aryl group, but is not limited thereto. The polycyclic aryl group may be a naphthyl group, anthracenyl group, phenanthryl group, pyrenyl group, perylenyl group, chrysenyl group, 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. However, it is not limited thereto.

In the present specification, the heterocyclic group is a heterocyclic group containing at least one of O, N, Si, and S as heterogeneous elements, and the number of carbon atoms is not particularly limited, but preferably has 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, and an acridyl group. , pyridazine group, pyrazinyl group, quinolinyl group, quinazoline group, quinoxalinyl group, phthalazinyl group, pyridopyrimidinyl group, pyridopyrazinyl group, pyrazinopyrazinyl 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 A zolyl group, a phenothiazinyl group, and a dibenzofuranyl group, but are not limited thereto.

In the present specification, an aralkyl group, an aralkenyl group, an alkylaryl group, and an aryl group among arylamine groups are the same as the examples 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 examples of the above-mentioned alkyl group. In the present specification, the description of the heterocyclic group described above may be applied to the heteroaryl of the heteroarylamine. In the present specification, the alkenyl group among the aralkenyl groups is the same as the examples of the alkenyl group described above. In the present specification, the description of the aryl group described above may be applied except that the arylene is a divalent group. In the present specification, the description of the heterocyclic group described above may be applied except that the heteroarylene is a divalent group. In the present specification, the hydrocarbon ring is not a monovalent group, and the description of the aryl group or cycloalkyl group described above may be applied, except that the hydrocarbon ring 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 provides a polymer including a repeating unit represented by Chemical Formula 1 above.

A conventionally used material for solution deposition has a problem in that, even if it has solubility in a solvent, the material is dissolved in a solvent used for deposition of the next layer, and the layer is mixed to deteriorate device performance.

However, as will be described in detail below, the polymer according to the present invention has excellent hole transport properties due to the repeating unit represented by Formula 1 and solvent orthogonality after deposition, thereby suppressing interlayer mixing.

By depositing and then curing the polymer according to the present invention to make the deposited polymer solvent resistant, it can be applied to an organic light emitting device through a solution process.

The polymer according to the present invention is dissolved in a solvent, applied through a solution process, and then cured through heat treatment or light treatment to prevent interlayer migration. At this time, in order not to damage the OLED element, it is important to completely cure at a temperature around 200 ° C. The materials developed in the present invention are cured at a temperature of around 200° C. and have good film properties.

In the present specification, a 'repeating unit' is a repeating unit represented by Formula 1 included in the polymer according to the invention, and has excellent hole transport properties.

Preferably, n is 1 or 2.

Preferably, a is 0 and b is 0 to 2.

Preferably, L is a single bond; or a substituent represented by Formula 2-1 below.

[Formula 2-1]

Preferably, R ₁ and R ₂ are each independently hydrogen; or methyl.

Preferably, Ar ₁ is phenyl substituted with C _1-10 alkyl or C _3-10 cycloalkyl; Biphenyl unsubstituted or substituted with C _1-10 alkyl; naphthyl unsubstituted or substituted with C _1-10 alkyl; or fluorenyl unsubstituted or substituted with C _1-10 alkyl.

Preferably, Ar ₂ is phenyl unsubstituted or substituted with C _1-10 alkyl; Biphenylyl unsubstituted or substituted with C _1-10 alkyl; or naphthyl unsubstituted or substituted with C _1-10 alkyl, more preferably Ar ₂ is phenyl substituted with C _1-10 alkyl; Biphenylyl unsubstituted or substituted with C _1-10 alkyl; or unsubstituted naphthyl.

Preferably, Formula 1 is a repeating unit represented by:

Meanwhile, the compound represented by Formula 1 is derived from a monomer represented by Formula 1-1 below:

[Formula 1-1]

In Formula 1-1, n, a, b, R ₁ , R ₂ , L, Ar ₁ and Ar ₂ are as defined in Formula 1 above.

(polymer)

The polymer according to the present invention may be prepared by polymerizing the monomer represented by Formula 1-1. Preferably, the polymer according to the present invention is a random copolymer including the repeating unit.

Preferably, the weight average molecular weight of the polymer is 10,000 to 500,000, more preferably 10,000 to 100,000.

(coating composition)

The polymer according to the present invention can form an organic material layer, particularly a hole transport layer, of an organic light emitting device through a solution process. To this end, the present invention provides a coating composition comprising the above-described polymer and a solvent according to the present invention.

The solvent is not particularly limited as long as it can dissolve or disperse the polymer according to the present invention. For example, chloroform, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, chlorobenzene, o -Chlorinated solvents such as dichlorobenzene; ether solvents such as tetrahydrofuran and dioxane; aromatic hydrocarbon solvents such as toluene, xylene, trimethylbenzene, and mesitylene; aliphatic hydrocarbon-based 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; Ethylene glycol, ethylene glycol monobutyl ether, ethylene glycol monoethyl ether, ethylene glycol monomethyl ether, dimethoxyethane, propylene glycol, diethoxymethane, triethylene glycol monoethyl ether, glycerin, 1,2-hexanediol, etc. alcohol and its derivatives; 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-phenoxy-toluene. In addition, the above-mentioned solvent may be used alone or in combination of two or more solvents.

In addition, the viscosity of the coating composition is preferably 1 cP to 10 cP, and coating is easy within the above range. In addition, the concentration of the polymer according to the present invention in the coating composition is preferably 0.1 wt / v% to 20 wt / v%.

In addition, the coating composition may further include one or two or more additives selected from the group consisting of a thermal polymerization initiator and a photopolymerization initiator.

As the thermal polymerization initiator, methyl ethyl ketone peroxide, methyl isobutyl ketone peroxide, acetylacetone peroxide, methylcyclohexanone peroxide, cyclohexanone peroxide, isobutyryl peroxide, 2,4-dichlorobenzoyl peroxide, oxide, such as bis-3,5,5-trimethylhexanoyl peroxide, lauryl peroxide, benzoyl peroxide, or the like, or azobis isobutylnitrile, azobisdimethylvaleronitrile, and azobis cyclohexyl nitrile. There is an azo type, but is not limited thereto.

As the photopolymerization initiator, diethoxy acetophenone, 2,2-dimethoxy-1,2-diphenyl ethan-1-one, 1-hydroxy-cyclohexyl-phenyl-ketone, 4-(2-hydroxyethoxy ) phenyl- (2-hydroxy-2-propyl) ketone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) butanone-1,2-hydroxy-2-methyl-1- Phenyl propan-1-one, 2-methyl-2-morpholino (4-methyl thiophenyl) propan-1-one, 1-phenyl-1,2-propanedione-2- (o-ethoxycarbonyl) acetophenone-based or ketal-based photopolymerization initiators such as oxime; benzoin ether-based photopolymerization initiators such as benzoin, benzoin methyl ether, and benzoin ethyl ether; benzophenone-based photopolymerization initiators such as benzophenone, 4-hydroxybenzophenone, 2-benzoylnaphthalene, 4-benzoylbiphenyl, and 4-benzoyl phenyl ether; thioxanthone-based photopolymerization initiators such as 2-isopropylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, and 2,4-dichlorothioxanthone; and ethyl anthraquinone, 2,4,6-trimethylbenzoyl diphenyl phosphine oxide, 2,4,6-trimethylbenzoyl phenyl ethoxy phosphine oxide, bis(2,4,6-trimethylbenzoyl) phenyl phosphine oxide, Other photopolymerization initiators such as, but not limited to, bis(2,4-dimethoxy benzoyl)-2,4,4-trimethyl pentylphosphine oxide.

In addition, those having a photopolymerization accelerating effect may be used alone or in combination with the photopolymerization initiator. Examples include triethanolamine, methyldiethanolamine, ethyl 4-dimethylaminobenzoate, isoamyl 4-dimethylaminobenzoate, (2-dimethylamino)ethyl benzoate, 4,4'-dimethylaminobenzophenone, etc. Not limited.

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

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

In the heat treatment step, the heat treatment temperature is preferably 150 to 230 °C. 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. In addition, a step of evaporating a solvent may be further included between the coating step and the heat treatment or light treatment step.

(organic light emitting element)

In addition, the present invention provides an organic light emitting device comprising the polymer according to the present invention described above. Specifically, the present invention is a positive electrode; a cathode provided to face the anode; a light emitting layer provided between the anode and the cathode; and a hole transport layer provided between the anode and the light emitting layer, wherein the hole transport layer includes the polymer according to the present invention.

The structure of an organic light emitting device according to an embodiment of the present invention is illustrated in FIGS. 1 and 2 .

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

The organic light emitting device according to the present invention may be manufactured using materials and methods known in the art, except that the hole transport layer includes the polymer according to the present invention and is manufactured as described above.

For example, the organic light emitting device according to the present invention may be manufactured by sequentially stacking an anode, an organic material layer, and a cathode on a substrate. At this time, using a physical vapor deposition (PVD) method such as sputtering or e-beam evaporation, depositing a metal or a metal oxide having conductivity or an alloy thereof on the substrate to form an anode After 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 depositing a material that can be used as a cathode thereon, it can be prepared.

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

As the anode material, a material having a high work function is generally preferred so that holes can be smoothly injected into the organic layer. Specific examples of the cathode material include metals such as vanadium, chromium, copper, zinc, and 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 so as to easily inject electrons 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; There are multi-layered materials such as LiF/Al or LiO ₂ /Al, but are not limited thereto.

The hole injection layer is a layer for injecting holes from the electrode, and the hole injection material has the ability to transport holes and has a hole injection effect at the anode, an excellent hole injection effect for the light emitting layer or the light emitting material, and generated in the light emitting layer A compound that prevents migration of excitons to the electron injecting layer or electron injecting material and has excellent thin film formation ability is preferred. It is preferable that the highest occupied molecular orbital (HOMO) of the hole injection material is between the work function of the anode material and the HOMO of the surrounding organic layer. Specific examples of the hole injection material include metal porphyrins, oligothiophenes, arylamine-based organic materials, hexanitrilehexaazatriphenylene-based organic materials, quinacridone-based organic materials, and perylene-based organic materials. of organic matter, anthraquinone, and polyaniline and polythiophene-based conductive polymers, but are not limited thereto.

The light emitting material is a material capable of emitting light in the visible ray region by receiving 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. Specific examples include 8-hydroxy-quinoline aluminum complex (Alq ₃ ); carbazole-based compounds; dimerized styryl compounds; BAlq; 10-hydroxybenzoquinoline-metal compounds; compounds of the benzoxazole, benzthiazole and benzimidazole series; poly(p-phenylenevinylene) (PPV)-based polymers; spiro compounds; Polyfluorene, rubrene, etc., but are not limited thereto.

The light emitting layer may include a host material and a dopant material. The host material includes a condensed aromatic ring derivative or a compound containing a hetero ring. Specifically, condensed aromatic ring derivatives include anthracene derivatives, pyrene derivatives, naphthalene derivatives, pentacene derivatives, phenanthrene compounds, fluoranthene compounds, etc., and heterocyclic-containing compounds include carbazole derivatives, dibenzofuran derivatives, ladder type furan compounds, pyrimidine derivatives, etc., but are not limited thereto.

Dopant materials include aromatic amine derivatives, strylamine compounds, boron complexes, fluoranthene compounds, metal complexes, and the like. Specifically, aromatic amine derivatives are condensed aromatic ring derivatives having a substituted or unsubstituted arylamino group, such as pyrene, anthracene, chrysene, periplanthene, etc. having an arylamino group, and styrylamine compounds include substituted or unsubstituted arylamine is substituted with at least one arylvinyl group, wherein 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, etc., but is not limited thereto. In addition, metal complexes include, but are not limited to, iridium complexes and platinum complexes.

The electron transport layer is a layer that receives electrons from the electron injection layer and transports electrons to the light emitting layer. As the electron transport material, a material capable of receiving electrons from the cathode and transferring them to the light emitting layer is suitable. Do. Specific examples include Al complexes of 8-hydroxyquinoline; Complexes containing 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 a layer of aluminum or silver. Specifically cesium, barium, calcium, ytterbium and samarium, followed in each case by a layer of aluminum or silver.

The electron injection layer is a layer for injecting electrons from an electrode, has the ability to transport electrons, has an excellent electron injection effect from a cathode, an excellent electron injection effect for a light emitting layer or a light emitting material, and injects holes of excitons generated in the light emitting layer. A compound that prevents migration to a layer and has excellent thin film forming ability is preferred. Specifically, fluorenone, anthraquinodimethane, diphenoquinone, thiopyran dioxide, oxazole, oxadiazole, triazole, imidazole, perylenetetracarboxylic acid, preonylidene methane, anthrone, etc. and their derivatives, 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)( There are o-cresolato) gallium, bis(2-methyl-8-quinolinato)(1-naphtolato)aluminum, and bis(2-methyl-8-quinolinato)(2-naphtolato)gallium. Not limited to this.

The organic light emitting device according to the present invention may be a top emission type, a bottom emission type, or a double side emission type depending on the material used.

In addition, the polymer according to the present invention may be included in an organic solar cell or an organic transistor in addition to an organic light emitting device.

Manufacturing of the polymer and the organic light emitting device including the polymer according to the present invention will be described in detail in the following examples. However, the following examples are intended to illustrate the present invention, and the scope of the present invention is not limited thereto.

[Preparation Example 1] Preparation of monomer 1

(Step 1-1)

In a round flask, 2,2'-dibromo-9,9'-spirobi[fluorene] (30,000 mg, 63.2644 mmol), bispinacolatodiborone (35,344 mg, 139.1818 mmol), [1,1'' -Bis(diphenylphosphino)ferrocene]dichloropalladium(II) (4,629 mg, 6.3264 mmol) and potassium acetate (13.659 mg, 139.1817 mmol) were added, and 310 ml of anhydrous dioxane was added. The flask is stirred for 12 hours while heating to 100 degrees. After lowering the temperature to room temperature, the reaction was terminated with water. Extraction was performed using 600 ml of ethyl acetate. 10 g of the target compound was obtained through recrystallization using a methylene chloride/hexane solvent.

(Steps 1-2)

In a round flask, the starting materials (1,000 mg, 1.7595 mmol), potassium carbonate (973 mg, 7.0382 mmol), tetrakis(triphenylphosphine)palladium(0) (203 mg, 0.1760 mmol), 1-bromo-4- After adding hexylbenzene (976 mg, 4.0469 mmol), 3 ml of anhydrous THF and 3 ml of water were added. The flask is stirred for 17 hours while heating to 90 degrees. After lowering the temperature to room temperature, the reaction is terminated with an aqueous solution of ammonium chloride. Extracted using methylene chloride. After removing the solvent, 768 mg of the target compound was obtained by column purification using a methylene chloride : hexane 1:5 solvent.

(Steps 1-3)

Put the starting material (4,130 mg, 6.4843 mmol) in a round flask and add 64 ml of anhydrous MC. While stirring at 0 degrees, bromine (0.9441 ml, 19.4529 mmol) was slowly added. The temperature was slowly raised to room temperature for 4 hours while stirring. The reaction is quenched with water. Extracted using methylene chloride. After removing the solvent, 5,200 mg of the target compound was obtained by column purification using a 1:9 ethyl acetate:hexane solvent.

(Steps 1-4)

In a round flask, starting material (5,200 mg, 6.5432 mmol), potassium carbonate (3,617 mg, 26.1728 mmol), tetrakis(triphenylphosphine)palladium(0) (756 mg, 0.6543 mmol), N-(4-(4) ,4,5,5-Tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)-[1,1'-biphenyl]-4-amine (5,344 mg, 14.3950 mmol) was added to anhydrous Add 25 ml of tetrahydrofuran (anhydrous THF) and 25 ml of water. The flask is stirred for 20 hours while heating to 90 degrees. After lowering the temperature to room temperature, the reaction is terminated with an aqueous solution of ammonium chloride. Extracted using methylene chloride. After removing the solvent, 6.67 g of the target compound was obtained by column purification using a 1:4 ethyl acetate:hexane solvent.

(Steps 1-5)

In a round flask, starting materials (6,670 mg, 5.9366 mmol), bromobenzene (1.31 ml, 12.4669 mmol), bis(tri-t-butylphosphine)palladium(0) (182 mg, 0.3562 mmol), sodium thiobutoxide (2,282 mg, 23.7464 mmol) and 84 ml of anhydrous toluene. The flask is stirred for 15 hours while heating to 90 degrees. After lowering the temperature to room temperature, the reaction is terminated with an aqueous solution of ammonium chloride. Extracted using methylene chloride. After removing the solvent, 6.1 g of the target compound was obtained by column purification using a methylene chloride:hexane 1:4 solvent.

(Steps 1-6) Synthesis of monomer 1

Put the starting material (1,140 mg, 1.0974 mmol) in a round flask and add 15 ml of anhydrous MC. The temperature of the reaction solution was lowered to 0 degrees and N-bromosercinimide (410 mg, 2.3045 mmol) was added while stirring. While slowly raising the temperature from 0 degrees to room temperature, the mixture was stirred for 4 hours. The reaction was terminated with water and extracted using methylene chloride. After removing the solvent, 1.37 g of [monomer 1] was obtained by column purification using a methylene chloride:hexane 1:4 solvent.

[Preparation Example 2] Preparation of monomer 2

(Step 2-1)

In a round flask, starting materials (2,000 mg, 2.5166 mmol), potassium carbonate (1,391 mg, 10.0664 mmol), tetrakis(triphenylphosphine)palladium(0) (291 mg, 0.2517 mmol), 4'-propyl-N- (4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)-[1,1'-biphenyl]-4-amine (2,289 mg, 5.5365 mmol), and 6 ml of anhydrous THF and 6 ml of water were added. The flask is stirred for 20 hours while heating to 90 degrees. After lowering the temperature to room temperature, the reaction is terminated with an aqueous solution of ammonium chloride. Extracted using methylene chloride. After removing the solvent, 2.1 g of the target compound was obtained by column purification using a 1:4 ethyl acetate:hexane solvent.

(Step 2-2) Synthesis of monomer 2

Starting material (1.8 g, 1.4904 mmol), 1-bromo-4-iodobenzene (1,290 mg, 4.5607 mol), copper iodide (142 mg, 0.7452 mmol), sodium-tert- After dissolving butoxide (716 mg, 7.452 mmol) and 1,10-phenanthroline (13 mg, 0.07452 mmol) in tetrahydrofuran (8 mL), the temperature was raised to 90 ^° C to react with reflux. After 24 hours, the temperature was lowered, dissolved in CH ₂ Cl ₂ and washed with water. Residual water (H ₂ O) was removed with MgSO ₄ , the solvent was removed, and 1.5 g of [Monomer 2] was obtained by recrystallization.

[Example 1] Preparation of Polymer 1

In a round flask, [monomer 1] (1,000 mg, 0.6976 mmol), [monomer A] (283 mg, 0.6976 mmol), bis(tri t-butylphosphine)palladium(0) (37 mg, 0.06976 mmol), potassium carbonate (964 mg, 6.976 mmol), and 4 ml of anhydrous THF and 4 ml of distilled water were added. Blow nitrogen into the round flask. Stir at 90 degrees for 17 hours. Molecular weight was confirmed by GPC. Add phenylboronic acid (340 mg, 2.7904 mmol) and stir overnight at 90 degrees. Add bromobenzene (0.292 ml, 2.7904 mmol) and stir overnight at 90 degrees. Methanol is added to precipitate. After dissolving the obtained solid in toluene, it was washed with hydrochloric acid, aqueous ammonia, and water. The resulting solution is treated with magnesium sulfate. After filtering with Florosil, 500 mg of the target compound was obtained through an aluminum oxide column.

Mn = 16,000, Mw = 22,000, PDI = 1.375

[Example 2] Preparation of Polymer 2

In a round flask, [monomer 2] (1,000 mg, 0.6976 mmol), [monomer B] (322 mg, 0.6976 mmol), bis(tri t-butylphosphine)palladium(0) (37 mg, 0.06976 mmol), potassium carbonate (964 mg, 6.976 mmol), and 4 ml of anhydrous THF and 4 ml of distilled water were added. Blow nitrogen into the round flask. Stir at 90 degrees for 17 hours. Molecular weight was confirmed by GPC. Add phenylboronic acid (340 mg, 2.7904 mmol) and stir overnight at 90 degrees. Add bromobenzene (0.292 ml, 2.7904 mmol) and stir overnight at 90 degrees. Methanol is added to precipitate. After dissolving the obtained solid in toluene, it was washed with hydrochloric acid, aqueous ammonia, and water. The resulting solution is treated with magnesium sulfate. After filtering with Florosil, 523 mg of the target compound was obtained through an aluminum oxide column.

Mn = 23,000, Mw = 37,000, PDI = 1.609

[Example 3] Preparation of Polymer 3

In a round flask, [monomer 2] (1,000 mg, 0.6976 mmol), [monomer C] (291 mg, 0.6976 mmol), bis(tri t-butylphosphine)palladium(0) (37 mg, 0.06976 mmol), potassium carbonate (964 mg, 6.976 mmol), and 4 ml of anhydrous THF and 4 ml of distilled water were added. Blow nitrogen into the round flask. Stir at 90 degrees for 17 hours. Molecular weight was confirmed by GPC. Add phenylboronic acid (340 mg, 2.7904 mmol) and stir overnight at 90 degrees. Add bromobenzene (0.292 ml, 2.7904 mmol) and stir overnight at 90 degrees. Methanol is added to precipitate. After dissolving the obtained solid in toluene, it was washed with hydrochloric acid, aqueous ammonia, and water. The resulting solution is treated with magnesium sulfate. After filtering with Florosil, 610 mg of the target compound was obtained through an aluminum oxide column.

Mn = 24,000, Mw = 40,000, PDI = 1.667

[Comparative Example 1] Preparation of Polymer X

[Polymer X] was prepared in the same manner as in Example 1, except that Monomer 3 was used instead of Monomer 1 in Example 1.

Mn = 14,000, Mw = 23,000, PDI = 1.643

[Experimental Example]

Experimental Example 1: Solubility measurement

Polymers 1 to 3 and Polymer X prepared in Examples and Comparative Examples are prepared in Table 1 below under a nitrogen atmosphere. It was added dropwise to 1 mL of each solvent and stirred at room temperature to prepare a coating composition. The results are shown in Table 1.

polymer menstruum Toluene THF Cyclohexanone EtOAc Diethyl ether Acetone Hexane polymer 1 28mg 24mg 11mg 14mg 7 mg 14mg 1mg polymer 2 31mg 30mg 14mg 28mg 13mg 18mg 1mg polymer 3 34 mg 29mg 17mg 26mg 17mg 24mg 2 mg Polymer X 14mg 7 mg 4 mg 1mg 0mg 0mg 0mg

* Toluene: Toluene / THF: Tetrahydrofuran / Cyclohexanone: Cyclohexanone / EtOAc: Ethyl acetate / Diethyl ether: Diethyl ether / Acetone: Acetone / Hexane: Hexane

From Table 1, it was confirmed that the polymer according to the present invention has excellent solubility in organic solvents.

Experimental Example 2: Preparation of organic light emitting device

A glass substrate coated with indium tin oxide (ITO) at a thickness of 1,500 A was placed in distilled water in which detergent was dissolved and washed with ultrasonic waves. At this time, a product of Fischer Co. was used as a detergent, and distilled water filtered through a second filter of a product of Millipore Co. was used as distilled water. After washing the ITO for 30 minutes, ultrasonic cleaning was performed twice with distilled water for 10 minutes. After washing with distilled water, ultrasonic cleaning was performed with solvents such as isopropyl alcohol, acetone, and methanol, dried, and transported to a plasma cleaner. In addition, after cleaning the substrate for 5 minutes using oxygen plasma, the substrate was transferred to a vacuum deposition machine.

A film having a thickness of 400 Å was formed on the prepared ITO transparent electrode by spin-coating a solution in which compound A and compound B were mixed in a weight ratio of 8:2 and dissolved in cyclohexanone. This was heated at 220 DEG C for 30 minutes in a nitrogen atmosphere to form a hole injection layer.

Thereafter, a coating composition prepared by dissolving the polymer of Table 2 in toluene at 2 wt% was applied, and then baked in air at 200° C. for 1 hour to obtain a uniform thin film. This is introduced into the vacuum deposition apparatus, and when the base pressure becomes 2 X 10 ^-5 Pa or less, a-NPD (40 nm), Alq ₃ (50 nm), LiF (0.5 nm), and Al (100 nm) are sequentially applied. An organic light emitting device was manufactured by vapor deposition. In the above process, the deposition rate of LiF was maintained at 0.01 to 0.05 nm/s, and the deposition rate of materials other than LiF was maintained at 0.1 to 0.5 nm/s.

[Compound A]

[Compound B]

Table 2 below shows the results of measuring driving voltage, current density, voltage efficiency, power efficiency, luminance, color coordinates, and lifetime of the prepared organic light emitting device at a current density of 10 mA/cm ² . At this time, T95 means the time required for the luminance to decrease from the initial luminance (500 nit) to 95%.

hole
transport layer polymer Voltage
(V) electric current
density
(mAcm ² ) Voltage
efficiency
(Cd/A) power
efficiency
(lm/W) luminance
(Cd/m ² ) CIEx CIEy T95 Example 1 polymer 1 4.23 10.00 5.67 4.21 442 0.137 0.097 92.0 Example 2 polymer 2 4.45 10.00 6.86 4.84 433 0.139 0.098 101.0 Example 3 polymer 3 4.64 10.00 6.81 4.61 433 0.138 0.098 99.0 Comparative Example 1 Polymer X 4.17 10.00 3.36 2.74 365 0.139 0.89 56

From Table 2, it can be confirmed that Examples 1 to 3 are superior to Comparative Example 1 in voltage efficiency, power efficiency, quantum efficiency, luminance and lifetime.

In addition, from Tables 1 and 2, the polymer according to the present invention has excellent solubility in organic solvents, so it is easy to prepare a coating composition, and a uniform coating layer can be formed using the prepared coating composition, and the stability of the film It was confirmed that it was excellent and exhibited better performance in an organic light emitting device.

Experimental Example 3: Solvent Resistance Evaluation

Solvent tolerance of the prepared polymer was evaluated using toluene.

Specifically, after preparing a solution in which polymer 2, polymer 3, and polymer X prepared above were dissolved in toluene at 2 wt%, it was coated on a quartz substrate to a thickness of 100 nm by spin coating. Thereafter, after heat treatment at 190 to 200 ° C. for 1 hour in a nitrogen atmosphere, UV-Vis absorption spectrum was measured. Subsequently, the same sample was immersed in toluene for 10 minutes and then taken out, and the UV-Vis absorption spectrum was measured again after the solvent was dried.

The measurement results are shown in FIG. 3 . As shown in Figure 3, the polymer according to the present invention showed a high membrane retention rate with respect to toluene.

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

Claims (10)

A polymer containing a repeating unit represented by Formula 1 below:
[Formula 1]

In Formula 1,
n is an integer from 1 to 5;
a and b are each independently an integer from 0 to 4;
L is a single bond; Or a substituent represented by Formula 2 below,
[Formula 2]

R ₁ to R ₄ are each independently hydrogen; heavy hydrogen; halogen; cyano; Substituted or unsubstituted C _1-60 Alkyl; Substituted or unsubstituted C _1-60 alkoxy; Substituted or unsubstituted C _1-60 thioalkyl; Substituted or unsubstituted C _3-60 cycloalkyl; Substituted or unsubstituted C _6-60 aryl; C _5-60 heteroaryl containing one or more heteroatoms selected from the group consisting of substituted or unsubstituted N, O and S; or tri(C _1-60 alkyl)silyl;
Ar ₁ is phenyl substituted with C _1-10 alkyl or C _3-10 cycloalkyl; substituted or unsubstituted C _10-60 aryl; Or a substituted or unsubstituted fluorenyl,
Ar ₂ is a substituted or unsubstituted C _6-60 aryl.
According to claim 1,
n is 1 or 2, a polymer.
According to claim 1,
a is 0 and b is 0 to 2, a polymer.
According to claim 1,
L is a single bond; Or a substituent represented by Formula 2-1, a polymer:
[Formula 2-1]

According to claim 1,
R ₁ and R ₂ are each independently hydrogen; or methyl, a polymer.
According to claim 1,
Ar ₁ is phenyl substituted with C _1-10 alkyl or C _3-10 cycloalkyl; Biphenyl unsubstituted or substituted with C _1-10 alkyl; naphthyl unsubstituted or substituted with C _1-10 alkyl; Or C _1-10 Alkyl substituted or unsubstituted fluorenyl, a polymer.
According to claim 1,
Ar ₂ is phenyl unsubstituted or substituted with C _1-10 alkyl; Biphenylyl unsubstituted or substituted with C _1-10 alkyl; Or a naphthyl unsubstituted or substituted with C _1-10 alkyl, a polymer.
According to claim 1,
Formula 1 is any one selected from the group consisting of a repeating unit represented by, a polymer.

According to claim 1,
The polymer has a weight average molecular weight of 10,000 to 500,000.
anode; a cathode provided to face the anode; a light emitting layer provided between the anode and the cathode; and a hole transport layer provided between the anode and the light emitting layer, wherein the hole transport layer includes the polymer according to any one of claims 1 to 9.

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