KR102336673B1 - Novel compound and organic light emitting device comprising the same - Google Patents

Abstract

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

Description

Novel compound and organic light emitting device comprising the same

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

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 material layer is often made of a multi-layer structure composed of different materials in order to increase the efficiency and stability of the organic light emitting device, for example, a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, It may be made of an electron injection layer, etc. 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 It lights up when it falls back to the ground state.

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

Meanwhile, in recent years, organic light emitting devices using a solution process, particularly an inkjet process, have been developed instead of the conventional deposition process in order to reduce process costs. In the early days, all organic light emitting device layers were coated with a solution process to develop an organic light emitting device, but the current technology has limitations. Therefore, only HIL, HTL, and EML are processed in the solution process in the regular structure, and subsequent processes are performed using the conventional deposition process. A hybrid process using

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

Korean Patent Publication No. 10-2000-0051826

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

The present invention provides a compound represented by the following formula (1):

[Formula 1]

In Formula 1,

R ₁ and R ₂ are each independently, or R ₁ or R ₂ are bonded to each other to form a C _6-60 aromatic ring,

L is a substituted or unsubstituted C _6-60 arylene; _{Or substituted or unsubstituted C 2-60} heteroarylene containing any one or more heteroatoms selected from the group consisting of N, O and S,

X is O, S, NZ ₃ , or SiZ ₄ Z ₅ ,

Z ₁ to Z ₅ are each independently, substituted or unsubstituted C _1-60 alkyl; substituted or unsubstituted C _1-60 haloalkyl; substituted or unsubstituted C _3-60 cycloalkyl; substituted or unsubstituted C _6-60 aryl; _{Or substituted or unsubstituted C 2-60} heteroaryl containing any one or more heteroatoms selected from the group consisting of N, O and S,

The L and Z ₂ , or Z ₂ and Z ₃ may be connected to each other to form a 5-membered heteroaromatic ring,

L ₁ and L ₂ are each independently, a single bond; substituted or unsubstituted C _6-60 arylene; _{Or substituted or unsubstituted C 2-60} heteroarylene containing any one or more heteroatoms selected from the group consisting of N, O and S,

Ar ₁ to Ar ₄ are each independently, substituted or unsubstituted C _6-60 aryl; _{or C 2-60} heteroaryl including any one or more heteroatoms selected from the group consisting of substituted or unsubstituted N, O and S.

In addition, the present invention is a first electrode; a second electrode provided to face the first electrode; and an emission layer provided between the first electrode and the second electrode, wherein the emission layer includes the compound represented by Formula 1 above.

The compound represented by Formula 1 described above can be used as a material for an organic material layer of an organic light emitting device, and can also be used in a solution process, and can improve efficiency, low driving voltage and/or lifespan characteristics in an organic light emitting device. have.

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

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

(Definition of Terms)

는 다른 치환기에 연결되는 결합을 의미하고, Ph는 페닐기를 의미하며, D는 중수소를 의미한다.In this specification,

denotes a bond connected to another substituent, Ph denotes a phenyl group, and D denotes deuterium.

As used herein, the term "substituted or unsubstituted" refers to deuterium; halogen group; cyano group; nitro group; hydroxyl group; carbonyl group; ester group; imid; amino group; a 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 atoms, which is substituted or unsubstituted with one or more substituents selected from the group consisting of heteroaryl containing one or more . 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 or 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, 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 number of carbon atoms in 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 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 phenanthrenyl 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, heteroaryl is a heteroaryl containing at least one of O, N, Si and S as a heterogeneous element, and the number of carbon atoms is not particularly limited, but is preferably from 2 to 60 carbon atoms. Examples of heteroaryl include xanthene, thioxanthen, thiophene, furan, pyrrole, imidazole, thiazole, oxazole, oxadiazole, triazole, pyridyl, bipyridyl, Pyrimidyl group, triazine group, 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 ( phenanthroline), an isoxazolyl group, a thiadiazolyl group, a phenothiazinyl group, and a dibenzofuranyl group, but are not limited thereto.

In the present specification, the aryl group in the aralkyl group, aralkenyl group, alkylaryl group, arylamine group, and arylsilyl group is the same as the above-described aryl group. 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 regarding heteroaryl described above 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 heteroaryl 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 regarding heteroaryl described above may be applied, except that it is formed by combining two substituents.

In the present specification, the aromatic ring refers to a condensed monocyclic or condensed polycyclic ring having aromaticity as a whole while including only carbon as a ring-forming atom. The number of carbon atoms of the aromatic ring is 6 to 60, or 6 to 30, or 6 to 20, but is not limited thereto. In addition, the aromatic ring may be a benzene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, a pyrene ring, and the like, but is not limited thereto.

(compound)

Meanwhile, the present invention provides a diamine compound represented by Formula 1 above.

The compound represented by Formula 1, as will be described in detail below, includes 'Z ₁ ' and 'LXZ ₂ ' as a substituent of a fluorene-based core, and 'Z ₁ ' and 'LXZ ₂ ' are different from each other, They have structures that are not connected to each other. Specifically, the compound having a structure in which the substituents of the fluorene-based core are the same or in which the substituents are connected to each other has a high crystallinity and has a low solubility in an organic solvent, whereas the compound represented by Formula 1 is Compared to this, since it has low crystallinity and exhibits increased solubility in an organic solvent used for a solution process, it is preferably used in a solution process when manufacturing an organic light emitting device.

Preferably, _{neither R 1} nor R ₂ is hydrogen.

Preferably, at least one of _{R 1} and R ₂ is combined with _{R 1} or R _{2 to form a C 6-60} aromatic ring, the rest are hydrogen, or combine with each other to form a C _6-60 aromatic ring .

More preferably, R ₁ and R ₂ are each independently hydrogen, or R ₁ or R ₂ are bonded to each other to form any one of structures represented by the following Chemical Formulas 2a to 2c:

* denotes a bonding position with the carbon bonded to _{R 1} or R _{2 .}

Specifically, at least one of _{R 1} and R _{2 is R 1} or R ₂ bonded to each other to form any one of the structures represented by Chemical Formulas 2a to 2c, and the remainder is hydrogen, or combined with each other to form any one of the structures represented by Chemical Formulas 2a to 2c. The structure represented by 2c can be formed.

More specifically, one of R ₁ and R ₂ may _{be combined with R 1} or R ₂ to form any one of the structures represented by Formulas 2a to 2c, and the remainder may be hydrogen.

Most preferably, R ₁ and R ₂ are each independently hydrogen, or R ₁ or R ₂ are bonded to each other to form a structure represented by Formula 2a.

For example, the compound represented by Formula 1 is

When _{all R 1} are hydrogen, and R ₂ are combined with each other to form a structure represented by Formula 2a, it is represented by Formula 1-1 below,

When R _{1 is} combined with each other to form a structure represented by Formula 2a, and R _{2 is} both hydrogen, it is represented by Formula 1-2:

[Formula 1-1]

[Formula 1-2]

In Formulas 1-1 and 1-2,

L, X, Z ₁ , Z ₂ , L ₁ , L _{2 ,} and Ar ₁ to Ar ₄ are as defined in Formula 1 above.

Preferably, Z ₁ is phenyl, biphenylyl, or naphthyl, wherein Z ₁ is unsubstituted or one or more deuterium, one or more C _1-10 alkyl, or one or more —Si(C _1-10 alkyl) ₃ .

More preferably, Z ₁ is phenyl, biphenylyl, or naphthyl, wherein Z ₁ is substituted with one or more deuterium, one or more methyl, one or more tert-butyl, or one or more —Si(methyl) _{3 .} .

Most preferably, Z ₁ is any one selected from the group consisting of:

.

.

Preferably, L is phenylene unsubstituted or substituted with _{C 1-10 alkyl.} More preferably, L is phenylene. Most preferably, L is 1,4-phenylene.

Preferably, Z ₂ to Z ₅ are each independently C _1-10 alkyl; _{or C 6-60} aryl unsubstituted or substituted with C _{1-10 alkyl.}

More preferably, Z ₂ and Z ₃ are each independently _{C 6-20} aryl which is unsubstituted or substituted with C _{1-10 alkyl.} In addition, Z ₄ and Z ₅ are each independently, C _1-10 alkyl; _{or C 6-20} aryl unsubstituted or substituted with C _{1-10 alkyl.}

At this time, 'the L and Z ₂ , or Z ₂ and Z ₃ may be connected to each other to form a 5-membered-heteroaromatic ring', the L and Z ₂ , or Z ₂ and Z ₃ each other linked to form a 5-membered-heteroaromatic ring containing O, S, N, or Si which is a heteroatom of X.

For example, in Formula 1, when L is 1,4-phenylene, Z ₂ is phenyl, and X is O, the compound has a structure represented by Formula 3a below, as well as L and Z ₂ It means that structures of the following formula (3b) are also possible, which are linked to each other to form a 5-membered-heteroaromatic ring containing a heteroatom O of X.

[Formula 3a] [Formula 3b]

In addition, for example, in Formula 1, when Z ₂ is all phenyl and X is N (phenyl), that is, when Z ₂ and Z ₃ are both phenyl, the compound is represented by Formula 3c In addition to the structure, it means that Z ₂ and Z ₃ are connected to each other to form a 5-membered heteroaromatic ring containing a heteroatom N of X, the structure of the following formula 3d is also possible.

[Formula 3c] [Formula 3d]

Most preferably, Z ₂ and Z ₃ are each independently phenyl, methylphenyl, or tert-butylphenyl, and Z ₄ and Z ₅ are each independently methyl, or phenyl.

Most preferably, LXZ ₂ is any one selected from the group consisting of:

above,

R and R' are each independently hydrogen, methyl, or tert-butyl.

Preferably, L ₁ and L ₂ are single bonds.

Preferably, Ar ₁ to Ar ₄ are each independently phenyl, naphthyl, or dibenzofuranyl, wherein Ar ₁ to Ar ₄ are unsubstituted, or at least one deuterium, or at least one C _1-10 substituted with alkyl.

More preferably, Ar ₁ to Ar ₄ are each independently phenyl, naphthyl, or dibenzofuranyl, wherein Ar ₁ to Ar ₄ are unsubstituted or one or more deuterium, methyl, or tert-butyl is replaced with

Most preferably, Ar ₁ to Ar ₄ are each independently any one selected from the group consisting of:

.

.

In this case, preferably, Ar ₁ and Ar ₄ are the same as each other, and Ar ₂ and Ar ₃ are the same as each other.

For example, the compound is any one selected from the group consisting of:

.

.

는 치환기

를 의미한다. At this time, among the substituents of the compounds

is a substituent

means

On the other hand, the compound represented by Formula 1, for example, when Ar ₁ and Ar ₄ are the same as each other and Ar ₂ and Ar ₃ are the same as each other, it can be prepared by the preparation method shown in Scheme 1 below.

[Scheme 1]

In Scheme 1, the definition of each substituent is the same as described above.

Step 1-1 is a step of preparing an intermediate compound INT.1 by introducing a hydroxyl group and compound SM2 into the starting material SM1 by a reduction reaction of a carbonyl group with a strong base, and Step 1-2 is a Friedel-Crafts type By introducing the compound SM3 into the hydroxyl group of the intermediate compound INT.1 by the electrophilic substitution reaction of This is a step of preparing a compound represented by Formula 1 by reacting SM4. Such a manufacturing method may be more specific in Preparation Examples to be described later.

(Coating composition)

On the other hand, the compound according to the present invention can form the organic material layer of the organic light emitting device, particularly the light emitting layer, by a solution process. Specifically, the compound may be used as a dopant material of the emission layer. To this end, the present invention provides a coating composition comprising the above-described compound according to the present invention and a solvent.

The solvent is not particularly limited as long as it is a solvent capable of dissolving or dispersing the compound according to the present invention, and for example, chloroform, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, chlorobenzene, o - Chlorine solvents, such as 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 butylbenzoate and methyl-2-methoxybenzoate; tetralin; Solvents, such as 3-phenoxytoluene, are mentioned. 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 a host material, a description of the compound used for the host material will be described later.

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 according to the present invention in the coating composition is preferably 0.1 wt/v% to 20 wt/v%.

In addition, the solubility (wt%) in the solvent of the coating composition is 1 wt% to 10 wt% based on the solvent toluene, and thus the coating composition including the compound represented by Formula 1 is suitable for use in a solution process do.

In addition, the present invention provides a method of forming a light emitting layer using the above-described coating composition. Specifically, 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 method, 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.

(organic light emitting element)

In addition, the present invention provides an organic light emitting device comprising the compound represented by Formula 1 above. In one example, the present invention provides a first electrode; a second electrode provided to face the first electrode; and an emission layer provided between the first electrode and the second electrode, wherein the emission layer includes the compound represented by Formula 1 above.

Also, the organic light emitting device according to the present invention may be a normal type organic light emitting device in which an anode, one or more organic material layers, and a cathode are sequentially stacked on a substrate. Also, the organic light emitting device according to the present invention may be an inverted type organic light emitting device in which a cathode, one or more organic material layers, and an anode are sequentially stacked on a substrate. For example, the structure of the organic light emitting diode 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 light emitting layer 3 , and a cathode 4 . In such a structure, the compound represented by Formula 1 may be included in the light emitting layer.

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

The organic light emitting device according to the present invention may be manufactured using materials and methods known in the art, except that the light emitting layer includes the compound 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, by using a PVD (physical vapor deposition) method such as sputtering or e-beam evaporation, a metal or a metal oxide having conductivity or an alloy thereof is deposited on a substrate to form an anode And, after forming an organic layer including a hole injection layer, a hole transport layer, a light emitting layer and an electron transport layer 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 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.

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.

In one example, the first electrode is an anode, the second electrode is a cathode, or the first electrode is a cathode and the second electrode is an anode.

As the anode material, a material having a large work function is generally preferred 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 compounds 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 multi-layered material such as LiF/Al or LiO ₂ /Al, but is not limited thereto.

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 on 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. It is preferable that 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 compounds, and the like, but are not limited thereto.

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

The emission layer may include a host material and a dopant material. As the dopant material, the compound represented by the above-described Chemical Formula 1 may be used. In addition, as a host material, a condensed aromatic ring derivative, a heterocyclic ring containing compound, etc. can be used. 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, and the like, but are not limited thereto.

The electron injection and transport layer is a layer that simultaneously serves as an electron transport layer and an electron injection layer for injecting electrons from the electrode and transporting the received electrons to the emission layer, and is formed on the emission layer or the electron control layer. As the electron injection and transport material, a material capable of receiving electrons from the cathode and transferring them to the light emitting layer is suitable, and a material having high electron mobility is suitable. Specific examples of the electron injection and transport material include Al complex of 8-hydroxyquinoline; complexes containing Alq _{3 ;} organic radical compounds; hydroxyflavone-metal complexes; and triazine derivatives, but is not limited thereto. or LiF, NaF, NaCl, CsF, Li ₂ O, BaO, fluorenone, anthraquinodimethane, diphenoquinone, thiopyran dioxide, oxazole, oxadiazole, triazole, imidazole, perylenetetracarboxylic acid, pre Orenylidene methane, anthrone, etc. derivatives thereof, metal complex compounds, or nitrogen-containing 5-membered ring derivatives may be used, but the present invention is 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.

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

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

The compound represented by Formula 1 and the preparation of an organic light emitting device including the same will be described in detail in Examples below. 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 Compound 1

Step 1-1: Synthesis of intermediate compound A3

Compound A2 (4.26 g, 20 mmol) was placed in 150 mL of tetrahydrofuran, cooled to −78° C. while stirring, and N-butyllithium 1.6 M (10.6 ml, 17 mmol) was added to the prepared solution for 1 hour. stirred. Next, Compound A1 (5.82 g, 15 mmol) was added, stirred for 1 hour, and then the temperature was raised to room temperature, followed by stirring for 2 hours. Thereafter, an aqueous solution of ammonium chloride was added, stirred for 30 minutes, and the organic layer was separated in a separatory funnel, and then _{water was removed using MgSO 4} , and then the solvent was removed under reduced pressure. The obtained material was subjected to column chromatography using dichloromethane and hexane to separate and purified Compound A3 (3.7 g, yield: 47%).

MS: [M+H] ⁺ = 521

Step 1-2: Synthesis of intermediate compound A5

Compound A3 (3.1 g, 6 mmol) prepared in step 1-1 was added to 60 mL of dichloromethane, cooled to 0° C. with stirring, and then methanesulfonic acid (1.2 g, 20 mmol) was added for 10 minutes, and the temperature was raised to room temperature. did Then, Compound A4 (3.2 g, 9 mmol) was added thereto and stirred for 30 minutes, then sodium bicarbonate aqueous solution was added and stirred for 30 minutes. Thereafter, the organic layer was separated in a separatory funnel _{to remove moisture using MgSO 4} , and then the solvent was removed under reduced pressure. The obtained material was subjected to column chromatography using dichloromethane and hexane to separate and purified Compound A5 (5.0 g, yield: 97%).

MS: [M+H] ⁺ = 860

Step 1-3: Synthesis of compound 1

Compound A5 (2.0 g, 2.32 mmol), Compound A6 (1.61 g, 5.10 mmol), Pd(P(tBu) ₃ ) ₂ (119 mg, 0.232 mmol) and Natert-BuO (0.74) prepared in Step 1-2 g, 7.66 mmol) was dissolved in toluene (25 ml), followed by stirring at 100° C. for 15 hours. After cooling to room temperature and adding distilled water, the organic layer was separated in a separatory funnel, _{water was removed using MgSO 4} , and the solvent was removed under reduced pressure. Compound 1 (1.3 g, yield: 42%) was isolated and purified by column chromatography on the obtained material using dichloromethane and hexane.

MS: [M+H] ⁺ = 1331

Preparation Example 2: Preparation of compound 2

Compound 2 (yield: 17%) was prepared in the same manner as in Preparation Example 1, except that A7 was used instead of Compound A4 in Preparation Example 1.

MS: [M+H] ⁺ = 1329

Preparation Example 3: Preparation of compound 3

Compound 3 (yield: 20%) was prepared in the same manner as in Preparation Example 1, except that A9 was used instead of Compound A4 in Preparation Example 1, and A11 was used instead of A6.

MS: [M+H] ⁺ = 1120

Preparation Example 4: Preparation of compound 4

Compound 4 (yield: 19%) was prepared in the same manner as in Preparation Example 1, except that A12 was used instead of Compound A2 in Preparation Example 1, and A14 was used instead of A4.

MS: [M+H] ⁺ = 1407

Preparation Example 5: Preparation of compound 5

Compound 5 (yield: 15%) was prepared in the same manner as in Preparation Example 3, except that A16 was used instead of A9 in Preparation Example 3.

MS: [M+H] ⁺ = 1136

Preparation Example 6: Preparation of compound 6

Step 6-1: Synthesis of compound A19

Compound A19 (3.96 g, yield: 49 %) was prepared in the same manner as in step 1-1, except that A18 was used instead of compound A2 in step 1-1.

MS: [M+H] ⁺ = 537

Step 6-2: Synthesis of compound A21

Compound A19 (2.69 g, 5 mmol) prepared in step 6-1 was added to A20 (200 mL) and cooled to 0° C. with stirring, and then methanesulfonic acid (1.2 g, 20 mmol) was added for 10 minutes, and then at 80° C. The temperature was raised. After stirring for 12 hours, after cooling to room temperature, sodium bicarbonate aqueous solution was added and stirred for 30 minutes. Thereafter, the organic layer was separated in a separatory funnel _{to remove moisture using MgSO 4} , and then the solvent was removed under reduced pressure. The obtained material was subjected to column chromatography to separate and purified Compound A21 (2.07 g, yield: 66%).

MS: [M+H] ⁺ = 625

Step 6-3: Synthesis of compound 6

Compound 6 (2.53 g, yield: 70 %) was prepared in the same manner as in step 1-3, except that A21 was used instead of compound A5 in step 1-3.

MS: [M+H] ⁺ = 1096

Experimental Example 1: Solubility Experiment

Compounds 1 to 4 and the following compounds BD prepared in Preparation Example were respectively dissolved in toluene to measure their solubility in toluene at room temperature/atmospheric pressure, and the results are shown in Table 1.

[Compound BD]

compound Solubility (wt%) compound 1 6.5 compound 2 6.0 compound 3 4.5 compound 4 6.0 compound 5 4.2 compound 6 5.1 compound BD 0.2

As shown in Table 1, it can be seen that the compound in which the substituent of the fluorene core represented by Formula 1 of the present invention is asymmetric has significantly higher solubility in toluene than the compound BD.

Example 1: Fabrication of an organic light emitting device

A glass substrate on which indium tin oxide (ITO) was deposited to a thickness of 500 Å was placed in distilled water in which detergent was dissolved and washed with ultrasonic waves. In this case, a product manufactured by Fisher Co. was used as the detergent, and distilled water filtered through a filter manufactured by Millipore Co. was used as the distilled water. After washing the ITO for 30 minutes, ultrasonic washing was performed for 10 minutes by repeating twice with distilled water. After washing with distilled water, ultrasonic washing was performed with acetone, distilled water, and isopropyl alcohol solvent and dried to prepare a cleaned ITO glass substrate with a thickness of 500 Å.

On the ITO transparent electrode, the following compound Z-1 and the following compound Z-2 were mixed in a weight ratio of 8:2, and a composition dissolved in toluene in a weight ratio of 2% was spin-coated, and under a nitrogen atmosphere at 220° C. and 30 minutes on a hot plate. was cured to form a hole injection layer having a thickness of 400 Å. On the hole injection layer, a composition obtained by dissolving the following compound Z-3 in toluene at a weight ratio of 1% was spin-coated and heat-treated on a hot plate at 200° C. for 30 minutes to form a hole transport layer having a thickness of 200 Å.

A 2 wt% toluene solution was prepared in which the following compound Z-4 and the compound 1 prepared in Preparation Example 1 were dissolved in a weight ratio of 94:6 on the hole transport layer, spin-coated at 5000 rpm, and baked at 80° C. for 2 minutes. ) and baked at 120° C. for 30 minutes to form a light emitting layer with a thickness of 550 Å.

After drying this at 130° C. for 10 minutes under a nitrogen atmosphere, lithium fluoride (LiF) was deposited on the light emitting layer to a thickness of 10 Å to form an electron transport and injection layer, and finally aluminum was deposited to a thickness of 1000 Å to form a cathode. did

In the above process, lithium fluoride was maintained at a deposition rate of 0.3 Å/sec, and aluminum was maintained at a deposition rate of 2 Å/sec, and the vacuum degree during deposition was maintained at 2×10 ^-7 to 5×10 ^-6 torr, thereby manufacturing an organic light emitting device.

Examples 2 to 6 and Comparative Example 1

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.

The compounds used in Examples 1 to 6 and Comparative Example 1 are summarized as follows:

Experimental Example 2: Evaluation of characteristics of organic light emitting devices

When a current was applied to the organic light-emitting devices prepared in Examples 1 to 4 and Comparative Example 1, the driving voltage, current efficiency, luminous efficiency, quantum efficiency, and lifetime were measured at a current density of ^{10 mA/cm 2} is shown in Table 2 below. In this case, the lifetime T90 means the time required for the luminance to decrease from the initial luminance (1000 nit) to 90%.

compound
(light emitting layer
dopant) drive voltage
(V
@10mA/cm ² ) luminous efficiency
(cd/A
@10mA/cm ² ) life span
(hr
@1000 nits) Example 1 compound 1 4.22 6.32 345 Example 2 compound 2 4.35 6.54 374 Example 3 compound 3 4.35 6.69 361 Example 4 compound 4 4.24 6.51 331 Example 5 compound 5 4.37 6.44 301 Example 6 compound 6 4.32 6.37 312 Comparative Example 1 compound BD 4.41 5.99 251

As shown in Table 2, the organic light emitting device using the compound of the present invention as a dopant for the light emitting layer is very superior in terms of driving voltage, efficiency and lifespan compared to the organic light emitting device using the compound BD of Comparative Example as a dopant for the light emitting layer. characteristics can be seen. In general, considering that the luminous efficiency and lifespan characteristics of the organic light emitting device have a trade-off relationship with each other, the organic light emitting device employing the compound of the present invention as a dopant of the light emitting layer is significantly improved compared to the comparative example device. It means that the device characteristics are shown.

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

Claims (12)

A compound represented by the following formula (1):
[Formula 1]

In Formula 1,
L is phenylene unsubstituted or substituted with _{C 1-10 alkyl,}
X is O, S, NZ ₃ , or SiZ ₄ Z ₅ ,
Z ₁ is phenyl, biphenylyl, or naphthyl;
wherein Z ₁ is unsubstituted or substituted with one or more deuterium, one or more C _1-10 alkyl, or one or more —Si(C _1-10 alkyl) ₃ ,
Z ₂ to Z ₅ are each independently, C _1-10 alkyl; _{or C 6-60} aryl unsubstituted or substituted with C _{1-10 alkyl;}
The L and Z ₂ , or Z ₂ and Z ₃ may be connected to each other to form a 5-membered heteroaromatic ring,
L ₁ and L ₂ are a single bond,
Ar ₁ to Ar ₄ are each independently phenyl, naphthyl, or dibenzofuranyl;
Here, Ar ₁ to Ar ₄ are unsubstituted or substituted with one or more deuterium, or one or more C _{1-10 alkyl.}
delete delete delete According to claim 1,
Z ₁ is any one selected from the group consisting of
compound:

.
According to claim 1,
LXZ ₂ is any one selected from the group consisting of
compound:

above,
R and R' are each independently hydrogen, methyl, or tert-butyl.
delete delete According to claim 1,
Ar ₁ to Ar ₄ are each independently any one selected from the group consisting of
compound:

.
According to claim 1,
Ar ₁ and Ar ₄ are the same as each other,
Ar ₂ and Ar ₃ are the same as each other,
compound.
According to claim 1,
The compound is any one selected from the group consisting of the following compounds,
compound:

.
a first electrode; a second electrode provided to face the first electrode; and a light emitting layer provided between the first electrode and the second electrode, wherein the light emitting layer comprises any one of claims 1, 5, 6, and 9 to 11. Which comprises a compound according to the, organic light emitting device.

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