KR102470630B1 - Organic light emitting device - Google Patents

Abstract

The present invention provides an organic light emitting device with improved driving voltage, efficiency and lifetime.

Description

Organic light emitting device {Organic light emitting device}

The present invention relates to an organic light emitting diode having improved driving voltage, efficiency and lifetime.

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.

In the organic light emitting device as described above, the development of an organic light emitting device with improved driving voltage, efficiency, and lifespan is continuously required.

Korean Patent Publication No. 10-2000-0051826

The present invention relates to an organic light emitting diode having improved driving voltage, efficiency and lifetime.

The present invention provides the following organic light emitting device:

Including an anode, a cathode, and a light emitting layer between the anode and the cathode,

The light emitting layer includes a first compound represented by Formula 1 and a second compound represented by Formula 2 below.

Organic Light-Emitting Elements:

[Formula 1]

In Formula 1,

A is a benzene ring fused with two adjacent pentagonal rings, respectively;

Ar ₁ to Ar ₃ are each independently a substituted or unsubstituted C _6-60 aryl; Or a substituted or unsubstituted C _5-60 heteroaryl containing at least one heteroatom selected from the group consisting of N, O and S,

R ₁ 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 _2-60 alkenyl; Substituted or unsubstituted C _2-60 alkynyl; Substituted or unsubstituted C _3-60 cycloalkyl; Substituted or unsubstituted C _6-60 aryl; Or a C _2-60 heteroaryl containing any one or more heteroatoms selected from the group consisting of substituted or unsubstituted N, O and S,

x is an integer from 1 to 10;

However, at least one of Ar ₁ to Ar ₃ and R ₁ is substituted with one or more deuterium, or at least one of R ₁ is deuterium, but the first compound is substituted with at least 5 deuterium,

[Formula 2]

In Formula 2,

B is a benzene ring fused with two adjacent pentagonal rings, respectively;

Ar ₄ is a substituted or unsubstituted C _6-60 aryl;

Ar ₅ is a substituted or unsubstituted C _6-60 aryl; Or a substituted or unsubstituted C _5-60 heteroaryl containing one heteroatom selected from the group consisting of N, O and S,

R ₂ 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 _2-60 alkenyl; Substituted or unsubstituted C _2-60 alkynyl; Substituted or unsubstituted C _3-60 cycloalkyl; Substituted or unsubstituted C _6-60 aryl; Or a C _2-60 heteroaryl containing any one or more heteroatoms selected from the group consisting of substituted or unsubstituted N, O and S,

y is an integer from 1 to 10;

The organic light emitting device described above has excellent driving voltage, efficiency and lifespan by including the first compound represented by Chemical Formula 1 and the second compound represented by Chemical Formula 2 in the light emitting layer.

1 shows an example of an organic light emitting device composed of a substrate 1, an anode 2, a light emitting layer 3, and a cathode 4.
2 shows a substrate 1, an anode 2, a hole injection layer 5, a hole transport layer 6, an electron blocking layer 7, a light emitting layer 3, a hole blocking layer 8, an electron injection and transport layer ( 9) and an example of an organic light emitting element composed of a cathode 4 is shown.

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 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 the following structure, 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 organic light emitting device according to the present invention has a structure in which an anode, a light emitting layer, and a cathode are sequentially stacked on a substrate (normal type), or an organic light emitting structure in which a cathode, a light emitting layer, and an anode are sequentially stacked on a substrate (inverted type) It may be a light emitting element. In addition, the organic light emitting device may optionally further include at least one layer of a hole injection layer, a hole transport layer, and an electron blocking layer between the anode and the light emitting layer, and between the cathode and the light emitting layer, a hole blocking layer, an electron blocking layer, and an electron blocking layer. At least one layer of an injection layer and an electron transport layer may be further included. In addition, the electron injection layer and the electron transport layer may be included as a single layer of electron injection and transport layers instead of separate layers.

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

anode and cathode

An anode and a cathode used in the present invention refer to electrodes used in an organic light emitting device.

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.

hole injection layer

The organic light emitting device according to the present invention may further include a hole injection layer on the anode, if necessary.

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. In addition, 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.

hole transport layer

The organic light emitting device according to the present invention may include a hole transport layer on the anode (or on the hole injection layer if the hole injection layer exists), if necessary.

The hole transport layer is a layer that receives holes from the anode or the hole injection layer and transports the holes to the light emitting layer. As a hole transport material, it is a material that receives holes from the anode or the hole injection layer and transfers them to the light emitting layer, and has hole mobility. Larger materials are suitable.

Specific examples of the hole transport material include, but are not limited to, arylamine-based organic materials, conductive polymers, and block copolymers having both conjugated and non-conjugated parts.

light emitting layer

The light emitting layer used in the present invention means a layer capable of emitting light in the visible ray region by combining holes and electrons transferred from the anode and the cathode. In general, the light emitting layer includes a host material and a dopant material, and in the present invention, the first compound represented by Chemical Formula 1 and the second compound represented by Chemical Formula 2 are included as hosts.

Preferably, the first compound represented by Chemical Formula 1 may be substituted with 5 or more deuterium atoms. Specifically, at least one of Ar ₁ to Ar ₃ , and R ₁ in Formula 1 is substituted with one or more deuterium, or at least one of R ₁ is deuterium, so that the first compound can have 5 or more deuterium atoms in the compound. , or 6 or more, or 7 or more, or 8 or more, or 10 or more deuterium, or the first compound may be completely substituted with deuterium.

Preferably, Formula 1 may be represented by any one selected from the group consisting of Formulas 1-1 to 1-6:

[Formula 1-1]

[Formula 1-2]

[Formula 1-3]

[Formula 1-4]

[Formula 1-5]

[Formula 1-6]

In Chemical Formulas 1-1 to 1-6, Ar ₁ to Ar ₃ , R ₁ , and x are as defined above.

In Formula 1, preferably, Ar ₁ to Ar ₃ are each independently phenyl, biphenyl, terphenyl, dibenzofuranyl, dibenzothiophenyl, fluorenyl, 9,9-dimethylfluorenyl, 9 ,9-diphenylfluorenyl, carbazol-9-yl, or 9-phenyl-9H-carbazolyl.

In Formula 1, more preferably, at least one of Ar ₁ to Ar ₃ is phenyl, and the others are each independently phenyl, biphenyl, terphenyl, dibenzofuranyl, dibenzothiophenyl, fluorenyl, 9 ,9-dimethylfluorenyl, 9,9-diphenylfluorenyl, carbazol-9-yl, or 9-phenyl-9H-carbazolyl.

In addition, at least one of Ar ₁ to Ar ₃ may be substituted with one or more deuterium. For example, at least one of Ar ₁ to Ar ₃ may be selected from the group consisting of the following structures:

In the above formula, a is an integer from 1 to 5,

b is an integer from 0 to 4, c is an integer from 0 to 5, but b and c are not 0 at the same time;

d is each independently an integer from 0 to 3, e is an integer from 0 to 5, but d and e are not 0 at the same time;

f is an integer from 0 to 3, g is independently an integer from 0 to 5, but f and g are not 0 at the same time;

h is an integer from 0 to 3, i is an integer from 0 to 4, but h and i are not 0 at the same time;

j is an integer from 0 to 3, k is an integer from 0 to 4, l is each independently an integer from 0 to 5, but j, k and l are not 0 at the same time,

m is an integer from 0 to 4, n is an integer from 0 to 4, but m and n are not 0 at the same time;

o is an integer from 0 to 3, p is an integer from 0 to 4, and q is an integer from 0 to 5, but o, p, and q are not 0 at the same time.

Also preferably, at least one of Ar ₁ to Ar ₃ may be substituted with 5 or more deuterium atoms.

More preferably, in Formula 1, at least one of Ar ₁ to Ar ₃ is phenyl substituted with 5 deuterium atoms, and the others are unsubstituted phenyl, biphenyl, terphenyl, dibenzofuranyl, dibenzothiocyanate Ofenyl, fluorenyl, 9,9-dimethylfluorenyl, 9,9-diphenylfluorenyl, carbazol-9-yl, or 9-phenyl-9H-carbazolyl.

In one example, the Ar ₁ to Ar ₃ are all phenyl, and the Ar ₁ to Ar ₃ are at least one of, specifically, any one, two, or all three of Ar ₁ to Ar ₃ to 5 deuterium atoms. can be substituted.

In another example, one of the Ar ₁ to Ar ₃ is unsubstituted, biphenyl, terphenyl dibenzofuranyl, dibenzothiophenyl, fluorenyl, 9,9-dimethylfluorenyl, 9, 9-diphenylfluorenyl, carbazol-9-yl, or 9-phenyl-9H-carbazolyl, the remainder being phenyl, wherein at least one of the remainder, i.e., one or both of the remainder, is 5 deuterium atoms can be replaced with

Also preferably, at least one of Ar ₁ to Ar ₃ is substituted with 5 or more deuterium atoms, biphenyl, terphenyl, dibenzofuranyl, dibenzothiophenyl, fluorenyl, 9,9-dimethyl fluorenyl, 9,9-diphenylfluorenyl, carbazol-9-yl, or 9-phenyl-9H-carbazolyl, and the others may each independently be unsubstituted phenyl or unsubstituted biphenyl. .

For example, one of Ar ₁ to Ar ₃ may be biphenyl substituted with 5 deuterium atoms, and the others may each independently be unsubstituted phenyl or unsubstituted biphenyl. At this time, biphenyl is substituted with 5 deuterium can be represented by the following structure as an example.

In the above formula, r is an integer from 0 to 4, more specifically 0.

In another example, two of Ar ₁ to Ar ₃ may be biphenyls substituted with 5 deuterium atoms, and the others may be unsubstituted phenyls. At this time, biphenyl is substituted with 5 deuterium can be represented by the above structure.

In another example, one of the Ar ₁ to Ar ₃ is completely substituted with deuterium, biphenyl, terphenyl, dibenzofuranyl, dibenzothiophenyl, fluorenyl, 9,9-dimethylfluorenyl , 9,9-diphenylfluorenyl, carbazol-9-yl, or 9-phenyl-9H-carbazolyl, and all others may be unsubstituted phenyl.

Also preferably, each of Ar ₁ to Ar ₃ is independently selected from phenyl, biphenyl, terphenyl, dibenzofuranyl, dibenzothiophenyl, fluorenyl, 9,9-dimethylfluorenyl, 9,9 -Diphenylfluorenyl, carbazol-9-yl, or 9-phenyl-9H-carbazolyl, and all of Ar ₁ to Ar ₃ may be completely substituted with deuterium.

Also, in Formula 1, preferably, all of R ₁ may be hydrogen. In this case, in Formula 1, x is an integer of 10, and at least one of Ar ₁ to Ar ₃ is substituted with 5 or more deuterium atoms.

Also, in Formula 1, preferably, at least 5 of R ₁ are deuterium, and the rest may be hydrogen. In this case, in Formula 1, x is an integer of 10. For example, in Chemical Formula 1, 5, 6, 7, or 8 of R ₁ may be deuterium and the rest may be hydrogen, or all 10 R ₁ may be deuterium.

Representative examples of the first compound represented by Formula 1 are as follows:

.

.

The first compound represented by Chemical Formula 1 may be prepared by, for example, a manufacturing method shown in Reaction Scheme 1 below.

[Scheme 1]

In Reaction Scheme 1, Ar ₁ to Ar ₃ , R ₁ , and x are as defined in Formula 1, and X is halogen, preferably chloro or bromo.

Reaction Scheme 1 is an amine substitution reaction, which is preferably carried out in the presence of a palladium catalyst and a base, and the reactor for the amine substitution reaction can be changed as known in the art. The manufacturing method may be more specific in Preparation Examples to be described later.

Meanwhile, Formula 2 may be preferably represented by any one selected from the group consisting of Formulas 2-1 to 2-6 below, and more preferably Formula 2 is represented by Formulas 2-1 to 2-3 below. It can be represented by any one selected from the group consisting of:

[Formula 2-1]

[Formula 2-2]

[Formula 2-3]

[Formula 2-4]

[Formula 2-5]

[Formula 2-6]

In Chemical Formulas 2-1 to 2-6, Ar ₄ , Ar ₅ , R ₂ , and y are as defined above.

In Formula 2, preferably Ar ₄ and Ar ₅ may each independently be an unsubstituted C _6-30 aryl, more preferably Ar ₄ and Ar ₅ each independently represent an unsubstituted phenyl, biphenyl, terphenyl, fluorenyl, 9,9-dimethylfluorenyl, or 9,9-diphenylfluorenyl.

In Formula 2, preferably, Ar ₄ is an unsubstituted C _6-30 aryl, and Ar ₅ is an unsubstituted C _5- containing one heteroatom selected from the group consisting of N, O, and S. ₆₀ heteroaryl, more preferably Ar ₄ is unsubstituted, phenyl, biphenyl or terphenyl, and Ar ₅ is unsubstituted, dibenzofuranyl, dibenzothiophenyl, carbazole-9- mono, or 9-phenyl-9H-carbazolyl.

In Formula 2, preferably, all of R ₂ may be hydrogen, and in this case, y may be an integer of 10.

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

.

.

The compound represented by Chemical Formula 2 can be prepared, for example, by a manufacturing method such as the following Reaction Scheme 2.

[Scheme 2]

In Reaction Scheme 2, Ar ₄ , Ar ₅ , R ₂ , and y are as defined in Formula 2 above, and Y is halogen, preferably chloro or bromo. Ar is as defined in Ar ₄ or Ar ₅ .

Reaction Scheme 2 is an amine substitution reaction, which is preferably carried out in the presence of a palladium catalyst and a base, and the reactor for the amine substitution reaction can be changed as known in the art. The manufacturing method may be more specific in Preparation Examples to be described later.

In Reaction Scheme 2, the reaction between Compound (III) and Compound (IV) is shown in one step. However, when Ar ₄ and Ar ₅ are different from each other in Compound (2), Ar in Compound (IV) is Ar ₄ and Ar ₅ It may be performed in two steps by changing the functional group corresponding to each. At this time, the order of the reaction steps is not particularly limited.

Preferably, the weight ratio of the first compound represented by Formula 1 and the second compound represented by Formula 2 in the light emitting layer is 10:90 to 90:10, more preferably 20:80 to 80:20, 30:70 to 70:30, 30:70 to 50:50, or 30:70 to 40:60.

Meanwhile, the light emitting layer may further include a dopant in addition to a host. The dopant material is not particularly limited as long as it is a material used in an organic light emitting device. For example, there are 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.

electron transport layer

The organic light emitting device according to the present invention may include an electron transport layer on the light emitting layer, if necessary.

The electron transport layer is a layer that receives electrons from the cathode or an electron injection layer formed on the cathode, transports electrons to the light emitting layer, and suppresses the transfer of holes in the light emitting layer. As an electron transport material, electrons are well injected from the cathode. As a material that can be received and transferred to the light emitting layer, a material having high electron mobility is suitable.

Specific examples of the electron transport material 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.

electron injection layer

The organic light emitting device according to the present invention may further include an electron injection layer on the light emitting layer (or on the electron transport layer if the electron transport layer exists), if necessary.

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. It is preferable to use a compound that prevents migration to a layer and has excellent thin film forming ability.

Specific examples of materials that can be used as the electron injection layer include fluorenone, anthraquinodimethane, diphenoquinone, thiopyran dioxide, oxazole, oxadiazole, triazole, imidazole, perylenetetracarboxylic acid, preore nylidene methane, anthrone, etc. and their derivatives, metal complex compounds, nitrogen-containing 5-membered ring derivatives, etc., 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.

organic light emitting device

The structure of the organic light emitting device according to the present invention is illustrated in FIGS. 1 and 2 . 1 shows an example of an organic light emitting device composed of a substrate 1, an anode 2, a light emitting layer 3, and a cathode 4. 2 shows a substrate 1, an anode 2, a hole injection layer 5, a hole transport layer 6, an electron blocking layer 7, a light emitting layer 3, a hole blocking layer 8, an electron injection and transport layer (9), and an example of an organic light emitting element composed of a cathode (4) is shown.

The organic light emitting device according to the present invention can be manufactured by sequentially stacking the above-described components. At this time, by 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 And, after forming each of the above-described layers thereon, it can be manufactured by depositing a material that can be used as a cathode thereon. In addition to this method, an organic light emitting device may be manufactured by sequentially depositing a cathode material on a substrate and an anode material in the reverse order of the above configuration (WO 2003/012890). In addition, the light emitting layer may be formed by a solution coating method as well as a vacuum deposition method of a host and a dopant. Here, the solution coating method means spin coating, dip coating, doctor blading, inkjet printing, screen printing, spraying, roll coating, etc., but is not limited to these.

Meanwhile, 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.

Hereinafter, a preferred embodiment is presented to aid understanding of the present invention. However, the following examples are only provided to more easily understand the present invention, and the content of the present invention is not limited thereby.

Synthesis Example 1-1: Synthesis of Compound 1-1

Step 1) Synthesis of Intermediate A

11,12-dihydroindolo[2,3-a]carbazole (15.0 g, 58.5 mmol), 1-bromobenzene-2,3,4,5,6-d5 (10.4 g, 64.4 mmol), bis( After adding tri-tert-butylphosphine)palladium(0) (Pd(Pt-Bu ₃ ) ₂ ) (0.6g, 1.2mmol), sodium tert-butoxide (NaOtBu)(8.4g, 87.8mmol), and toluene 500ml, argon The mixture was stirred for 8 hours under reflux conditions. After the reaction was completed, after cooling to room temperature, H2O was added and the reaction solution was transferred to a separatory funnel and extracted. The extract was dried over MgSO4, concentrated, and the sample was purified by silica gel column chromatography to obtain 13.2 g of Intermediate A. (Yield 67%, MS[M+H]+= 337)

Step 2) Synthesis of Compound 1-1

In a three-necked flask, intermediate A (13.0 g, 38.5 mmol), compound a (14.6 g, 42.4 mmol), bis(tri-tert-butylphosphine)palladium(0) (0.4 g, 0.8 mmol), sodium tert-butoxide (5.6 g, 57.8 mmol) and 400 ml of xylene were added, followed by stirring for 8 hours under reflux conditions in an argon atmosphere. After the reaction was completed, after cooling to room temperature, H ₂ O was added and the reaction solution was transferred to a separatory funnel and extracted. After drying and concentrating the extract with MgSO ₄ and purifying the sample with silica gel column chromatography, 7.9 g of Compound 1-1 was obtained through sublimation purification. (Yield 32%, MS[M+H]+= 644)

synthesis example 1-2: Synthesis of compound 1-2

In step 1 of Synthesis Example 1-1, 1-bromobenzene-2,3,4,5,6-d5 was changed to bromobenzene to prepare intermediate B, and in step 2, compound a was changed to compound b. Except for the above, Compound 1-2 was prepared in the same manner as in Compound 1-1. (MS[M+H] ⁺ = 644)

Synthesis Example 1-3: Synthesis of Compound 1-3

Compound 1-3 was prepared in the same manner as in Compound 1-1, except that Compound a was changed to Compound c in Step 2 of Synthesis Example 1-1. (MS[M+H] ⁺ = 649)

Synthesis Example 1-4: Synthesis of Compound 1-4

In step 1 of Synthesis Example 1-1, 1-bromobenzene-2,3,4,5,6-d5 was changed to bromo-1,1'-biphenyl to prepare intermediate C, and in step 2, compound a Compound 1-4 was prepared by the same preparation method as the preparation method of compound 1-1, except that was changed to compound d. (MS[M+H] ⁺ = 649)

Synthesis Example 1-5: Synthesis of Compound 1-5

Step 1) Synthesis of Intermediate 1-5-1

In a three-necked flask, intermediate C (15.0 g, 36.7 mmol), compound e (13.9 g, 40.4 mmol), bis(tri-tert-butylphosphine)palladium(0) (0.4 g, 0.7 mmol), sodium tert-butoxide (5.3 g, 55.1 mmol) and 400 ml of xylene were added, and stirred for 8 hours under reflux conditions in an argon atmosphere. After the reaction was completed, after cooling to room temperature, H2O was added and the reaction solution was transferred to a separatory funnel and extracted. The extract was dried over MgSO ₄ and concentrated, and the sample was purified by silica gel column chromatography to obtain 17.1 g of Intermediate 1-5-1. (Yield 65%, MS[M+H]+= 715)

Step 2) Synthesis of Compounds 1-5

Compound 1-5-1 (10.0 g, 14.0 mmol), PtO ₂ (1.0 g, 4.2 mmol), and 70 ml of D2O were added to a shaker tube, and then the tube was sealed and heated at 250° C. and 600 psi for 12 hours. When the reaction was completed, chloroform was added and the reaction solution was transferred to a separatory funnel and extracted. The extract was dried with MgSO ₄ , concentrated, and the sample was purified by silica gel column chromatography, and 4.4 g of Compound 1-5 was obtained through sublimation purification. (Yield 42%, deuterium substitution rate 82%, MS[M+H]+= 749)

Synthesis Example 1-6: Synthesis of Compound 1-6

Compound 1-6 was prepared in the same manner as in Compound 1-1, except that Intermediate A was changed to Intermediate B and Compound a was changed to Compound f in Step 2 of Synthesis Example 1-1. (MS[M+H] ⁺ = 658)

Synthesis Example 1-7: Synthesis of Compound 1-7

In step 1 of Synthesis Example 1-1, 1-bromobenzene-2,3,4,5,6-d5 was converted to 2-bromodibenzo[b,d] furan-1,3,4,6,7,8,9-d7 was used to prepare intermediate D, and compound 1-7 was prepared in the same manner as in compound 1-1, except that compound a was changed to compound g in step 2. (MS[M+H] ⁺ = 660)

Synthesis Example 1-8: Synthesis of Compound 1-8

Compound 1-8 was prepared in the same manner as in Compound 1-1, except that Intermediate A was changed to Intermediate B and Compound a was changed to Compound h in Step 2 of Synthesis Example 1-1. (MS[M+H] ⁺ = 733)

Synthesis Example 1-9: Synthesis of Compound 1-9

Except for changing 11,12-dihydroindolo[2,3-a]carbazole to 5,8-dihydroindolo[2,3-c]carbazole in Step 1 of Synthesis Example 1-1, Compound 1-1 Compounds 1-9 were prepared by the same preparation method as the preparation method. (MS[M+H] ⁺ = 644)

Synthesis Example 1-10: Synthesis of Compound 1-10

In step 1 of Synthesis Example 1-1, 11,12-dihydroindolo[2,3-a]carbazole was converted to 5,7-dihydroindolo[2,3-b]carbazole, 1-bromobenzene-2,3,4,5, Intermediate F was prepared by changing 6-d5 to bromobenzene, and compound 1-10 was prepared by the same method as in compound 1-1, except that compound a was changed to compound c in step 2. did (MS[M+H] ⁺ = 644)

Synthesis Example 1-11: Synthesis of Compound 1-11

In step 1 of Synthesis Example 1-1, 11,12-dihydroindolo[2,3-a]carbazole was changed to 5,11-dihydroindolo[3,2-b]carbazole to prepare intermediate G, and in step 2 Compound 1-11 was prepared in the same manner as in Compound 1-1, except that compound a was changed to compound i. (MS[M+H] ⁺ = 674)

Synthesis Example 1-12: Synthesis of Compound 1-12

Step 1) Synthesis of Intermediate H

In a three-necked flask, 5,12-dihydroindolo[3,2-a]carbazole (10.0 g, 39.0 mmol), compound j (16.7 g, 42.9 mmol), bis(tri-tert-butylphosphine) palladium(0) (0.4 g , 0.8mmol), sodium tert-butoxide (5.6g, 58.5mmol), and 400ml of toluene were added, and the mixture was stirred for 8 hours under reflux conditions in an argon atmosphere. After the reaction was completed, after cooling to room temperature, H ₂ O was added and the reaction solution was transferred to a separatory funnel and extracted. The extract was dried over MgSO ₄ , concentrated, and the sample was purified by silica gel column chromatography to obtain 16.9 g of intermediate H. (Yield 71%, MS[M+H]+= 608)

Step 2) Synthesis of Compounds 1-12

In a three-necked flask, intermediate H (15.0 g, 24.6 mmol), bromobenzene (4.3 g, 27.1 mmol), bis(tri-tert-butylphosphine)palladium(0) (0.3 g, 0.5 mmol), sodium tert-butoxide (3.6 g , 37.0 mmol) and 250 ml of xylene were added, followed by stirring for 8 hours under reflux conditions in an argon atmosphere. After the reaction was completed, after cooling to room temperature, H ₂ O was added and the reaction solution was transferred to a separatory funnel and extracted. The extract was dried with MgSO ₄ , concentrated, and the sample was purified by silica gel column chromatography, and 5.4 g of Compound 1-12 was obtained through sublimation purification. (Yield 32%, MS[M+H]+= 684)

Synthesis Example 1-13: Synthesis of Compound 1-13

In step 1 of Synthesis Example 1-1, 11,12-dihydroindolo[2,3-a]carbazole was converted to 5,12-dihydroindolo[3,2-a]carbazole, and 1-bromobenzene-2,3,4,5 ,6-d5 was changed to bromobenzene to prepare intermediate I, and compound 1-13 was prepared in the same manner as in compound 1-1, except that compound a was changed to compound k in step 2. was manufactured. (MS[M+H] ⁺ = 657)

synthesis example 1-14: Synthesis of compound 1-14

In step 1 of Synthesis Example 1-1, 11,12-dihydroindolo[2,3-a]carbazole was converted to 11,12-dihydroindolo[2,3-a]carbazole-1,3,5,6,8,10- Intermediate J was prepared using d6, and 1-bromobenzene-2,3,4,5,6-d5 was changed to 3-bromo-1,1':3',1''-terphenyl, Step 2 Compound 1-14 was prepared in the same manner as in Compound 1-1, except that compound a was changed to compound 1 in . (MS[M+H] ⁺ = 723)

synthesis example 1-15: Synthesis of compound 1-15

In step 1 of Synthesis Example 1-1, 11,12-dihydroindolo[2,3-a]carbazole was converted to 11,12-dihydroindolo[2,3-a]carbazole-1,2,3,4,5,6, 7,8,9,10-d10, and 1-bromobenzene-2,3,4,5,6-d5 was changed to 3-bromo-1,1':3',1''-terphenyl using Compound 1-15 was prepared in the same manner as in Compound 1-1, except that Intermediate K was prepared and Compound a was changed to Compound m in Step 2. (MS[M+H] ⁺ = 803)

Synthesis Example 2-1: Synthesis of Compound 2-1

In a nitrogen atmosphere, 5,8-dihydroindolo[2,3-c]carbazole (15.0g, 58.5mmol) and 4-bromo-1,1'-biphenyl (30.0g, 128.8mmol) were added to 300ml of toluene and stirred and refluxed. . After that, sodium tert-butoxide (16.9g, 175.6mmol) and bis(tri-tert-butylphosphine)palladium(0) (0.9g, 1.8mmol) were added. After reacting for 12 hours, the mixture was cooled to room temperature, and the organic layer was separated using chloroform and water, and then the organic layer was distilled. This was dissolved in chloroform again, and after washing twice with water, the organic layer was separated, stirred with anhydrous magnesium sulfate, filtered, and the filtrate was distilled under reduced pressure. After the concentrated compound was purified by silica gel column chromatography, 9.8 g of Compound 2-1 was prepared through sublimation purification. (Yield 30%, MS: [M+H]+= 562)

Synthesis Example 2-2: Synthesis of Compound 2-2

Step 1) Synthesis of Intermediate 2-1-1

5,8-dihydroindolo[2,3-c]carbazole (15.0 g, 58.5 mmol) and 4-bromo-1,1':4',1''-terphenyl (19.9 g, 64.4 mmol) were mixed with toluene in a nitrogen atmosphere. It was added to 300 ml and stirred and refluxed. After that, sodium tert-butoxide (8.4g, 87.8mmol) and bis(tri-tert-butylphosphine)palladium(0) (0.9g, 1.8mmol) were added. After reacting for 11 hours, the mixture was cooled to room temperature, and the organic layer was separated using chloroform and water, and then the organic layer was distilled. This was dissolved in chloroform again, and after washing twice with water, the organic layer was separated, stirred with anhydrous magnesium sulfate, filtered, and the filtrate was distilled under reduced pressure. The concentrated compound was purified by silica gel column chromatography to prepare 19.3 g of intermediate 2-2-1. (Yield 68%, MS: [M+H]+= 486)

Step 2) Synthesis of Compound 2-2

Intermediate 2-2-1 (15.0 g, 31.0 mmol) and 3-bromo-1,1'-biphenyl (7.9 g, 34.0 mmol) were added to 300 ml of toluene and stirred and refluxed in a nitrogen atmosphere. After that, sodium tert-butoxide (4.5g, 46.4mmol) and bis(tri-tert-butylphosphine)palladium(0) (0.5g, 0.9mmol) were added. After reacting for 7 hours, the mixture was cooled to room temperature, and the organic layer was separated using chloroform and water, and then the organic layer was distilled. This was dissolved in chloroform again, and after washing twice with water, the organic layer was separated, stirred with anhydrous magnesium sulfate, filtered, and the filtrate was distilled under reduced pressure. After the concentrated compound was purified by silica gel column chromatography, 9.5 g of compound 2-2 was prepared through sublimation purification. (Yield 48%, MS: [M+H]+= 638)

Synthesis Example 2-3: Synthesis of Compound 2-3

In step 1 of Synthesis Example 2-2, 5,8-dihydroindolo[2,3-c]carbazole was converted to 5,11-dihydroindolo[3,2-b]carbazole, and 4-bromo-1,1':4',1''-terphenyl to 4-bromo-1,1'-biphenyl, 3-bromo-1,1'-biphenyl to 4-chloro-1,1':3',1''-terphenyl in step 2 Compound 2-3 was prepared by the same preparation method as the preparation method of compound 2-2, except that it was changed to and used. (MS[M+H] ⁺ = 638)

Synthesis Example 2-4: Synthesis of Compound 2-4

In step 1 of Synthesis Example 2-2, 5,8-dihydroindolo[2,3-c]carbazole was converted to 5,12-dihydroindolo[3,2-a]carbazole, 4-bromo-1,1':4' ,Except for using 2-bromodibenzo[b,d]furan for 1''-terphenyl and 3-bromo-1,1'-biphenyl for 4-bromo-1,1'-biphenyl in step 2. , Compound 2-4 was prepared by the same preparation method as that of compound 2-2. (MS[M+H] ⁺ = 576)

Example 1

A glass substrate coated with ITO (Indium Tin Oxide) to a thickness of 1,400 Å was put in distilled water in which detergent was dissolved and washed with ultrasonic waves. At this time, a Fischer Co. product was used as the detergent, and distilled water filtered through a second filter of a Millipore Co. product was used as the 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.

On the prepared ITO transparent electrode, the following HT-A and 5% by weight of PD were thermally vacuum deposited to a thickness of 100 Å to form a hole injection layer, and then only the HT-A material was deposited to a thickness of 1150 Å to form a hole transport layer. HT-B was thermally vacuum deposited thereon to a thickness of 450 Å as an electron suppression layer. Subsequently, Compound 1-1 and Compound 2-1 were vacuum-deposited to a thickness of 400 Å in a weight ratio of 40:60, and 8% by weight of GD as a dopant for the host of the light emitting layer. Subsequently, as a hole blocking layer, the following ET-A was vacuum deposited to a thickness of 50 Å. Subsequently, on the hole blocking layer, ET-B and Liq were thermally vacuum deposited to a thickness of 250 Å in a ratio of 2: 1, followed by vacuum deposition of LiF and magnesium to a thickness of 30 Å in a ratio of 1: 1, forming an electron transport layer. and an electron injection layer were sequentially formed. An organic light emitting device was manufactured by depositing magnesium and silver to a thickness of 160 Å at a ratio of 1:4 on the electron injection layer to form a cathode.

Examples 2 to 23 and Comparative Examples 1 to 20

The organic light emitting diodes of Examples 2 to 23 and Comparative Examples 1 to 20 were manufactured in the same manner as in Example 1, except that the host material was changed as shown in Table 1 below. At this time, when a mixture of two types of compounds is used as a host, the weight ratio between the host compounds is indicated in parentheses.

Experimental Example: Evaluation of Device Characteristics

Voltage, efficiency, and lifetime (T95) were measured by applying current to the organic light emitting devices manufactured in the above Examples and Comparative Examples, and the results are shown in Table 1 below. At this time, the voltage and efficiency were measured by applying a current density of 10 mA/cm ² , and T95 denotes the time (hr) until the initial luminance decreases to 95% at a current density of 20 mA/cm ² .

host
matter @ 10mA/cm ² @ 20mA/cm ² Voltage
(V) efficiency
(cd/A) life span
(T95, hr) Example 1 Compound 1-1: Compound 2-1
(40:60) 4.01 64.1 132 Example 2 Compound 1-2: Compound 2-1 (40:60) 4.00 64.1 135 Example 3 Compound 1-3: Compound 2-1 (40:60) 4.01 64.2 143 Example 4 Compound 1-4: Compound 2-1 (40:60) 4.08 62.2 138 Example 5 Compound 1-5: Compound 2-1 (40:60) 4.02 64.3 152 Example 6 Compound 1-6: Compound 2-1 (40:60) 4.07 64.7 145 Example 7 Compound 1-7: Compound 2-1 (40:60) 4.08 64.2 130 Example 8 Compound 1-8: Compound 2-1 (40:60) 4.05 64.1 128 Example 9 Compound 1-9: Compound 2-1 (40:60) 4.17 63.7 133 Example 10 Compound 1-10: Compound 2-1 (40:60) 4.16 64.2 130 Example 11 Compound 1-11: Compound 2-1 (40:60) 4.13 63.8 131 Example 12 Compound 1-12: Compound 2-1 (40:60) 4.19 64.7 127 Example 13 Compound 1-13: Compound 2-1 (40:60) 4.21 62.9 137 Example 14 Compound 1-14: Compound 2-1 (40:60) 4.03 65.1 138 Example 15 Compound 1-15: Compound 2-1 (40:60) 4.07 64.9 141 Example 16 Compound 1-1: Compound 2-2 (40:60) 4.03 64.6 135 Example 17 Compound 1-2: Compound 2-2 (40:60) 4.02 64.5 130 Example 18 Compound 1-2: Compound 2-3 (40:60) 4.07 63.1 122 Example 19 Compound 1-3: Compound 2-3 (40:60) 4.08 63.2 128 Example 20 Compound 1-4: Compound 2-3 (40:60) 4.09 63.3 125 Example 21 Compound 1-5: Compound 2-4 (40:60) 4.11 64.1 141 Example 22 Compound 1-6: Compound 2-4 (40:60) 4.18 64.0 130 Example 23 Compound 1-10: Compound 2-4 (30:70) 4.21 63.1 119 Comparative Example 1 compound 1-1 4.71 54.1 91 Comparative Example 2 Compounds 1-6 4.67 52.7 84 Comparative Example 3 compound 2-1 7.62 7.5 5 Comparative Example 4 compound 2-3 7.82 5.8 3 Comparative Example 5 Compound GH-1-A: Compound 2-1 (40:60) 4.02 62.5 82 Comparative Example 6 Compound GH-1-B: Compound 2-1 (40:60) 4.23 61.7 71 Comparative Example 7 Compound GH-1-C: Compound 2-1 (40:60) 4.65 56.6 85 Comparative Example 8 Compound GH-1-A: Compound 2-2 (40:60) 4.07 62.3 86 Comparative Example 9 Compound GH-1-B: Compound 2-3 (40:60) 4.35 58.2 65 Comparative Example 10 Compound 1-1: Compound GH-2-A (40:60) 4.51 56.6 90 Comparative Example 11 Compound 1-1: Compound GH-2-B (40:60) 4.57 57.7 92 Comparative Example 12 Compound 1-1: Compound GH-2-C (40:60) 4.48 55.7 93 Comparative Example 13 Compound 1-6: Compound GH-2-B (40:60) 4.51 56.5 103 Comparative Example 14 Compound GH-1-A: Compound GH-2-D (40:60) 4.02 62.5 82 Comparative Example 15 Compound 1-1: Compound GH-2-E (40:60) 5.51 31.0 21 Comparative Example 16 Compound 1-1: Compound GH-2-F (40:60) 5.23 42.3 40 Comparative Example 17 Compound 1-1: Compound GH-2-G (40:60) 5.07 44.5 51 Comparative Example 18 Compound GH-1-A 4.71 54.2 60 Comparative Example 19 Compound GH-1-B 4.83 50.3 53 Comparative Example 20 Compound GH-2-A 7.76 6.7 8

In the present invention, both the first compound represented by Chemical Formula 1 and the second compound represented by Chemical Formula 2 have an indolocarbazole skeleton. Here, the first compound contains a triazine group and has a strong ability to transport electrons, and the second compound has a strong ability to transport holes, and thus has properties suitable for using a mixture of the two materials as a host. In particular, since both materials have an indolocarbazole structure, they are well mixed with each other to form an exciplex and to effectively transfer energy to a dopant. At this time, the first compound becomes an anion and the second compound becomes a cation to form an exciplex. The first compound, which becomes an anion, has a more unstable state. By substituting five or more deuterium here, the first compound has lower vibrational energy and more stable energy even in an anionic state.

As a result, as can be seen in Table 1, Examples 1 to 23 in which the first compound represented by Chemical Formula 1 and the second compound represented by Chemical Formula 2 in the present invention were used together as the light emitting layer of the organic electroluminescent device are comparative examples. It exhibited significantly improved low voltage, high efficiency, and long lifespan characteristics compared to others.

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

Claims (15)

Including an anode, a cathode, and a light emitting layer between the anode and the cathode,
The light emitting layer includes a first compound represented by Formula 1 and a second compound represented by Formula 2 below.
Organic Light-Emitting Elements:
[Formula 1]

In Formula 1,
A is a benzene ring fused with two adjacent pentagonal rings, respectively;
Ar ₁ to Ar ₃ are each independently a substituted or unsubstituted C _6-60 aryl; Or a substituted or unsubstituted C _5-60 heteroaryl containing at least one heteroatom selected from the group consisting of N, O and S,
R ₁ 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 _2-60 alkenyl; Substituted or unsubstituted C _2-60 alkynyl; Substituted or unsubstituted C _3-60 cycloalkyl; Substituted or unsubstituted C _6-60 aryl; Or a C _2-60 heteroaryl containing any one or more heteroatoms selected from the group consisting of substituted or unsubstituted N, O and S,
x is an integer from 1 to 10;
However, at least one of Ar ₁ to Ar ₃ and R ₁ is substituted with one or more deuterium, or at least one of R ₁ is deuterium, and the first compound contains at least 5 deuterium,
[Formula 2]

In Formula 2,
B is a benzene ring fused with two adjacent pentagonal rings, respectively;
Ar ₄ is a substituted or unsubstituted C _6-60 aryl;
Ar ₅ is a substituted or unsubstituted C _6-60 aryl; Or a substituted or unsubstituted C _5-60 heteroaryl containing one heteroatom selected from the group consisting of N, O and S,
R ₂ 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 _2-60 alkenyl; Substituted or unsubstituted C _2-60 alkynyl; Substituted or unsubstituted C _3-60 cycloalkyl; Substituted or unsubstituted C _6-60 aryl; Or a C _2-60 heteroaryl containing any one or more heteroatoms selected from the group consisting of substituted or unsubstituted N, O and S,
y is an integer from 1 to 10;
According to claim 1,
Formula 1 is represented by any one selected from the group consisting of Formulas 1-1 to 1-6,
Organic Light-Emitting Elements:
[Formula 1-1]

[Formula 1-2]

[Formula 1-3]

[Formula 1-4]

[Formula 1-5]

[Formula 1-6]

In Chemical Formulas 1-1 to 1-6, Ar ₁ to Ar ₃ , R ₁ , and x are as defined in claim 1.
According to claim 1,
Ar ₁ to Ar ₃ are each independently phenyl, biphenyl, terphenyl, dibenzofuranyl, dibenzothiophenyl, fluorenyl, 9,9-dimethylfluorenyl, 9,9-diphenylfluorenyl , which is carbazol-9-yl, or 9-phenyl-9H-carbazolyl;
organic light emitting device.
According to claim 1,
At least one of Ar ₁ to Ar ₃ is phenyl;
the others are each independently phenyl, biphenyl, terphenyl, dibenzofuranyl, dibenzothiophenyl, fluorenyl, 9,9-dimethylfluorenyl, 9,9-diphenylfluorenyl, carbazole- 9-yl, or 9-phenyl-9H-carbazolyl,
organic light emitting device.
According to claim 1,
At least one of Ar ₁ to Ar ₃ is phenyl substituted with 5 deuterium atoms;
The rest are unsubstituted, phenyl, biphenyl, terphenyl, dibenzofuranyl, dibenzothiophenyl, fluorenyl, 9,9-dimethylfluorenyl, 9,9-diphenylfluorenyl, carbazole -9-yl, or 9-phenyl-9H-carbazolyl,
organic light emitting device.
According to claim 1,
One of Ar ₁ to Ar ₃ is biphenyl, terphenyl, dibenzofuranyl, dibenzothiophenyl, fluorenyl, 9,9-dimethylfluorenyl, 9,9, which is substituted with 5 or more deuterium atoms. -diphenylfluorenyl, carbazol-9-yl, or 9-phenyl-9H-carbazolyl;
the others are each independently unsubstituted phenyl or unsubstituted biphenyl,
organic light emitting device.
According to claim 1,
Ar ₁ to Ar ₃ are each independently phenyl, biphenyl, terphenyl, dibenzofuranyl, dibenzothiophenyl, fluorenyl, 9,9-dimethylfluorenyl, 9,9-diphenylfluorenyl , carbazol-9-yl, or 9-phenyl-9H-carbazolyl;
Ar ₁ to Ar ₃ are all completely substituted with deuterium,
organic light emitting device.
According to claim 1,
wherein R ₁ is all hydrogen,
organic light emitting device.
According to claim 1,
At least 5 of the R ₁ are deuterium and the others are hydrogen,
organic light emitting device.
According to claim 1,
The first compound is any one selected from the group consisting of,
Organic Light-Emitting Elements:

.
According to claim 1,
Formula 2 is represented by any one selected from the group consisting of Formulas 2-1 to 2-6,
Organic Light-Emitting Elements:
[Formula 2-1]

[Formula 2-2]

[Formula 2-3]

[Formula 2-4]

[Formula 2-5]

[Formula 2-6]

In Chemical Formulas 2-1 to 2-6, Ar ₄ , Ar ₅ , R ₂ , and y are as defined in claim 1.
According to claim 1,
Ar ₄ and Ar ₅ are each independently unsubstituted, phenyl, biphenyl, terphenyl, fluorenyl, 9,9-dimethylfluorenyl, or 9,9-diphenylfluorenyl;
organic light emitting device.
According to claim 1,
Ar ₄ is unsubstituted, phenyl, biphenyl or terphenyl;
Ar ₅ is unsubstituted dibenzofuranyl, dibenzothiophenyl, carbazol-9-yl, or 9-phenyl-9H-carbazolyl;
organic light emitting device.
According to claim 1,
R ₂ are all hydrogen;
organic light emitting device.
According to claim 1,
The second compound is any one selected from the group consisting of,
Organic Light-Emitting Elements:

.

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