WO2019083167A1 - Organic electroluminescent element using compound for organic electroluminescent element and electronic device comprising same - Google Patents

Abstract

Disclosed are: an organic electroluminescent element comprising a compound represented by chemical formula 1 as a material for an auxiliary light emitting layer; and an electronic device comprising the same, wherein the auxiliary light emitting layer comprises the compound represented by chemical formula 1, thereby lowering a driving voltage of the organic electroluminescent element and improving light-emitting efficiency and lifespan thereof.

Description

Organic electric field device using compound for organic electric field element and electronic device thereof

The present invention relates to an organic electroluminescent device using an organic electroluminescent compound and an electronic device therefor.

In general, organic light emission phenomenon refers to a phenomenon in which an organic material is used to convert electric energy into light energy. An organic electric field element using an organic light emitting phenomenon usually has a structure including an anode, a cathode, and an organic layer between the anode and the cathode. Here, in order to increase the efficiency and stability of the organic field device, the organic material layer is often formed of a multi-layered structure made 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.

Currently, the portable display market is increasing in size as a large-area display, which requires more power than the power consumption required by existing portable displays. Therefore, power consumption becomes a very important factor for portable displays, which have a limited power source, such as a battery, and efficiency and lifetime issues must be solved.

The efficiency, lifetime, and driving voltage are related to each other. As the efficiency increases, the driving voltage decreases. As the driving voltage decreases, the crystallization of the organic material due to Joule heating, which occurs during driving, Indicating a tendency for the lifetime to increase. However, simply improving the organic material layer can not maximize the efficiency. This is because, when the optimal combination of the energy level and T1 value between each organic material layer and the intrinsic properties (mobility, interface characteristics, etc.) of the material are achieved, long life and high efficiency can be achieved at the same time.

Generally, electrons are transferred from the electron transport layer to the light emitting layer, and holes are transferred from the hole transport layer to the light emitting layer to generate excitons by recombination. However, since the material used for the hole transport layer has a low HOMO value, it has a low T ₁ value. As a result, the exciton generated in the light emitting layer is transferred to the hole transport layer. As a result, charge unbalance ) And causes light emission in the hole transporting layer or at the interface of the hole transporting layer, thereby lowering the color purity, decreasing the efficiency and decreasing the lifetime.

In addition, when a material having a high hole mobility is used to make a low driving voltage, the efficiency tends to decrease. Since the hole mobility is faster than the electron mobility in a general organic electroluminescent device, charge unbalance is caused in the light emitting layer, resulting in reduction in efficiency and lifetime.

Recently, in order to solve the problem of light emission in the hole transporting layer in the organic electroluminescent device, a light emitting auxiliary layer is formed between the hole transporting layer and the light emitting layer. It is time to develop.

The light emitting auxiliary layer should be formed of a material having a hole mobility, a high T ₁ (electron block) value, and a wide band gap so as to have a proper driving voltage capable of solving the problems of the hole transporting layer. These requirements are not met by the structural characteristics of the core of the light-emitting auxiliary layer material, and when the characteristics of the core and the sub-substituent of the material are all suitably combined, the efficiency and lifetime of the organic electric field element It is urgently required to develop a light emitting auxiliary layer material having a high T ₁ value and a wide band gap.

That is, in order to sufficiently exhibit the excellent characteristics of the organic electroluminescent device, a material constituting the organic material layer in the device such as a hole injecting material, a hole transporting material, a light emitting material, an electron transporting material, an electron injecting material, The organic material layer for an organic electroluminescent device has not been sufficiently developed yet. Therefore, development of new materials is continuously required, and development of materials for the light-emitting auxiliary layer is urgently required.

An object of the present invention is to provide an organic electroluminescent device using a compound capable of improving a high luminous efficiency, a low driving voltage, a high heat resistance, a color purity and a lifetime of a device as a light emitting auxiliary layer material, and an electronic device thereof.

In one aspect, the present invention provides an organic electroluminescent device including a first electrode, a second electrode, and an organic layer formed between the first electrode and the second electrode. Here, the organic material layer includes a light-emission-assisting layer formed between the first electrode and the light-emitting layer, and the light-emission-assisting layer includes a compound represented by the following formula.

In another aspect, the present invention provides an electronic device including the organic electroluminescent device.

By using the compound according to an embodiment of the present invention as a light emitting auxiliary layer material, it is possible not only to lower the driving voltage of the organic field effect device, but also to greatly improve the luminous efficiency, color purity and lifetime of the device.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an illustration of an organic electroluminescent device according to the present invention. FIG.

[Description of Symbols]

100: organic field element 110: substrate

120: first electrode 130: hole injection layer

140: Hole transport layer 141: Buffer layer

150: light emitting layer 151: light emitting auxiliary layer

160: electron transport layer 170: electron injection layer

180: second electrode

The term " fluorenyl group " or " fluorenylene group " used in the present invention means a monovalent or divalent functional group in which R, R 'and R & Substituted fluorenyl group "or" substituted fluorenylene group "means that at least one of the substituents R, R 'and R" is a substituent other than hydrogen, and R and R' Together with a spy compound.

The term " heterocyclic group " used in the present invention means a ring containing a hetero atom such as N, O, S, P or Si instead of carbon forming a ring, and the term "heteroaryl group" or "heteroarylene group" As well as non-aromatic rings, and compounds containing hetero atoms such as SO ₂ , P═O, etc., such as the following compounds, instead of ring-forming carbon, may also be included.

The term " spiro compound " used in the present invention has a 'spiro union', and a spiro connection means a connection in which two rings share only one atom. At this time, atoms shared in two rings are called 'spyro atoms', and they are referred to as 'monospyros,' 'di spyroses,' and 'tri-spyros', depending on the number of spyro atoms contained in a compound. 'Compounds.

Unless otherwise expressly stated, the formula used in the present invention is applied in the same manner as the definition of the substituent by the definition of the index of the following formula.

When a is an integer of 0, substituent R ¹ is absent. When a is an integer of 1, one substituent R ¹ is bonded to any one of carbon atoms forming a benzene ring, and when a is an integer of 2 or 3 each coupled as follows: and wherein R ¹ may be the same or different from each other, a is the case of 4 to 6 integer, and bonded to the carbon of the benzene ring in a similar way, while the display of the hydrogen bonded to the carbon to form a benzene ring Is omitted.

Hereinafter, the lamination structure of the organic electroluminescent device including the compound of the present invention will be described with reference to FIG.

FIG. 1 is a view illustrating a stacked structure of organic electroluminescent devices according to an embodiment of the present invention.

1, an organic electroluminescent device 100 according to the present invention includes a first electrode 120, a second electrode 180, a first electrode 110, and a second electrode 180 formed on a substrate 110, ) Comprising an organic compound layer comprising a compound according to the present invention. In this case, the first electrode 120 may be an anode and the second electrode 180 may be a cathode (cathode). In case of an inverting type, the first electrode may be a cathode and the second electrode may be an anode.

The organic material layer may include a hole injecting layer 130, a hole transporting layer 140, a light emitting layer 150, an electron transporting layer 160, and an electron injecting layer 170 sequentially on the first electrode 120. At this time, at least one of these layers may be omitted, or a hole blocking layer, an electron blocking layer, a light emitting auxiliary layer 151 and a buffer layer 141 may be further included, and the electron transporting layer 160 may serve as a hole blocking layer You can do it.

Also, although not shown, the organic electroluminescent device according to the present invention may further include a protective layer or a light-efficiency-improving layer formed on at least one surface of the first electrode and the second electrode opposite to the organic material layer.

The compound according to the present invention applied to the organic material layer includes a hole injecting layer 130, a hole transporting layer 140, an electron transporting layer 160, an electron injecting layer 170, a light emitting layer 150, a light efficiency improving layer, And the like. For example, the compound of the present invention can be used as the material of the hole transporting layer 140 and / or the light emitting auxiliary layer 151.

On the other hand, since the band gap, the electrical characteristics, the interface characteristics, and the like can be changed depending on which substituent is bonded at any position even in the same core, the selection of the core and the combination of the sub-substituents bonded thereto are very important, When the optimal combination of the energy level and T ₁ value between each organic material layer and the intrinsic properties (mobility, interfacial characteristics, etc.) of the materials are achieved, long lifetime and high efficiency can be achieved at the same time.

As described above, in order to solve the light emission problem in the hole transporting layer in recent organic electroluminescent devices, it is preferable to form a light emission assisting layer between the hole transporting layer and the light emitting layer, and to correspond to each of the light emitting layers (R, G and B) It is necessary to form different light-emission-assisting layers. On the other hand, in the case of the light-emission-assisting layer, it is difficult to deduce the characteristics of the organic layer to be used even if a similar core is used because the relationship between the hole-transport layer and the light-emitting layer (host)

Therefore, by forming the hole transporting layer and / or the light-emitting auxiliary layer using the compound of the present invention, it is possible to optimize the energy level and the T ₁ value between the respective organic layers, the mobility of the material, The lifetime and efficiency of the device can be improved at the same time.

The organic electroluminescent device according to an embodiment of the present invention may be manufactured using various deposition methods. For example, a metal or a metal oxide having conductivity or an alloy thereof may be deposited on a substrate to form a cathode 120, and a hole injection layer 130 may be formed thereon. A hole transport layer 140, a light emitting layer 150, an electron transport layer 160, and an electron injection layer 170, and then depositing a material that can be used as a cathode 180 on the organic layer. have. Further, a light emitting auxiliary layer 151 may be further formed between the hole transport layer 140 and the light emitting layer 150.

In addition, the organic material layer may be formed by using various polymer materials in a solution process or a solvent process such as a spin coating process, a nozzle printing process, an inkjet printing process, a slot coating process, a dip coating process, a roll- A screen printing process, a thermal transfer process, or the like. Since the organic material layer according to the present invention can be formed by various methods, the scope of the present invention is not limited by the forming method.

The organic electroluminescent device according to the present invention may be one of an organic electroluminescent (OLED), an organic solar cell, an organic photoconductor (OPC), an organic transistor (organic TFT), a monochromatic or white illumination device, or a device for a quantum dot display.

Another embodiment of the present invention may include an electronic device including a display device including the organic electroluminescent device of the present invention and a control unit for controlling the display device. At this time, the electronic device may be a current or future wired or wireless communication terminal and includes all electronic devices such as a mobile communication terminal such as a mobile phone, a PDA, an electronic dictionary, a PMP, a remote controller, a navigation device, The display device may include an organic electroluminescent display, a quantum dot display, and the like.

Hereinafter, an organic electroluminescent device according to one aspect of the present invention will be described.

According to an embodiment of the present invention, there is provided an organic electroluminescent device including a first electrode, a second electrode, and an organic layer formed between the first electrode and the second electrode. Here, the organic material layer may include a light emitting auxiliary layer formed between the first electrode and the light emitting layer, and the light emitting auxiliary layer may include a compound represented by the following general formula (1).

≪ Formula 1 >

In the above formula (1), each symbol may be defined as follows.

R ^a1 , R ^b1 , R ^a2 and R ^b2 are each independently a C ₁ to C ₅₀ alkyl group; A C ₆ to C ₆₀ aryl group; A fluorenyl group; And a C ₂ to C ₆₀ heterocyclic group containing at least one heteroatom selected from O, N, S, Si and P;

R ^a1 and R ^b1 may combine with each other to form a ring, and R ^a2 and R ^{b2 may} also combine with each other to form a ring, for example, a C ₆ to C ₆₀ aromatic hydrocarbon; A fluorenyl group; A C ₂ to C ₆₀ heterocyclic group containing at least one heteroatom selected from O, N, S, Si and P; A C ₃ to C ₆₀ aliphatic ring; A fused ring group of an aliphatic ring of C ₃ to C ₆₀ and an aromatic ring of C ₆ to C ₆₀ ; Or a combination thereof. Preferably, R ^a1 and R ^b1 and / or R ^a2 and R ^b2 may combine with each other to form a C ₆ -C ₆₀ ring containing a benzene ring.

When R ^a1 , R ^b1 , R ^a2 and R ^b2 are alkyl groups, it is preferably a C ₁ -C ₁₀ alkyl group, more preferably a C ₁ -C ₄ alkyl group, specifically methyl, ethyl, have. When R ^a1 , R ^b1 , R ^a2 and R ^b2 are aryl groups, it is preferably a C ₆ to C ₃₀ aryl group or a C ₆ to C ₂₀ aryl group, more preferably a C ₆ to C ₁₈ aryl group, Such as phenyl, naphthalene, biphenyl, terphenyl and the like, and most preferably phenyl.

When R ^a1 and R ^b1 and / or R ^a2 and R ^b2 are bonded to each other to form a ring containing a benzene ring, preferably a C ₆ to C ₂₁ ring, more preferably a C ₆ to C ₁₃ ring And when R ^b1 and / or R ^a2 and R ^b2 are bonded to each other to form a fused ring of an aromatic ring and an aliphatic ring, preferably a C ₃ to C ₃₀ aliphatic ring and a C ₆ to C ₃₀ Of fused rings of aromatic hydrocarbons, more preferably fused rings of C ₃ to C ₁₈ aliphatic rings and C ₆ to C ₁₈ aromatic hydrocarbons. For example, R ^a1 and R ^b1 and / or R ^a2 and R ^b2 may be bonded to each other to form a dihydroindene or a derivative thereof, a fluorene or a derivative thereof, and consequently share a carbon atom with the pentagonal ring to which they are bonded. Whereby a compound can be formed by spiraling.

Preferably, at least one of R ^a1 , R ^b1 , R ^a2 and R ^b2 is a methyl group or phenyl, or R ^a1 and R ^b1 are bonded to each other to form a fluorene, a benzofluorene, or a dibenzofluorene, R ^a2 and R ^b2 may combine with each other to form fluorene, benzofluorene, or dibenzofluorene. Also preferably, R ^a1 , R ^b1 , R ^a2 and R ^b2 are both methyl groups, all are phenyl or all may be fluorene, R ^a1 and R ^b1 are methyl or phenyl, R ^a2 and R ^b2 may form a fluorene ring, or conversely, R ^a1 and R ^b1 may form a fluorene ring, and R ^a2 and R ^b2 may all be methyl or phenyl.

R ¹ to R ⁷ independently from each other are hydrogen; heavy hydrogen; halogen; A C ₆ to C ₆₀ aryl group; A fluorenyl group; A C ₂ to C ₆₀ heterocyclic group containing at least one heteroatom selected from O, N, S, Si and P; A fused ring group of an aliphatic ring of C ₃ to C ₆₀ and an aromatic ring of C ₆ to C ₆₀ ; A C ₁ to C ₅₀ alkyl group; An alkenyl group having ₂ to ₂₀ carbon atoms; An alkynyl group having ₂ to ₂₀ carbon atoms; A C ₁ to C ₃₀ alkoxyl group; An aryloxy group of C ₆ to C ₃₀ ; And -L'-N (R ') (R "); or neighboring groups may be bonded to each other to form a ring.

Neighboring R ¹ , adjacent R ² , neighboring R ³ , neighboring R ⁴ , neighboring R ⁵ , neighboring R ⁶ , and / or neighboring R ⁷ are combined to form a ring C ₆ to C ₆₀ aromatic hydrocarbons; A fluorenyl group; A C ₂ to C ₆₀ heterocyclic group containing at least one heteroatom selected from O, N, S, Si and P; A C ₃ to C ₆₀ aliphatic ring; A fused ring group of an aliphatic ring of C ₃ to C ₆₀ and an aromatic ring of C ₆ to C ₆₀ ; Or a combination thereof, and is preferably a C ₆ -C ₂₀ aromatic hydrocarbon including a benzene ring, more preferably a C ₆ -C ₁₈ aromatic hydrocarbon such as benzene, naphthalene And so on. Therefore, naphthalene, phenanthrene and the like may be formed together with the benzene rings in which neighboring groups are bonded to each other to which they are bonded.

Preferably, R ^a1 , R ^b1 , R ^a2 and R ^b2 are independently of each other a C ₁ -C ₁₀ alkyl group, a C ₆ -C ₂₀ aryl group, or R ^a1 and R ^b1 and / or R ^a2 and R ^b2 are bonded to each other to form a C ₆ to C ₂₁ ring including a benzene ring, and R ¹ to R ⁷ independently of each other are bonded to each other to form a C ₆ to C ₂₀ ring containing a benzene ring .

More ^{preferably, R a1, R b1, R} a2 and R ^b2 are independently is an alkyl group of C ₁ ~ C ₄ to each other, C ₆ ~, or aryl group of C _18, R ^a1 and R ^b1 and / or R ^a2 and R ^b2 are bonded to each other to form a C ₆ to C ₁₃ ring containing a benzene ring and at least one pair of adjacent groups of R ¹ to R ⁷ are bonded to each other to form a C ₆ to C ₁₂ aromatic Hydrocarbons can be formed.

For example, R ^a1, R ^b1, R ^a2 and R ^b2 may have independently a methyl group or a phenyl group, or R ^a1 and R ^b1 and / or R ^a2 and R ^b2 each other may form a fluoren-bond to one another, R ¹ to R group between at least one pair of adjacent of ⁷ may form a benzene ring bonded to each other.

a, c, e and g is an integer of 0 ~ 4, b, d and f is 0-3 integer and each is 2 or more integer, orally, a plurality of each of a plurality of each of R ¹ to these R ⁷ are each, respectively They may be the same or identical to each other.

Ar ¹ is a C ₆ to C ₆₀ aryl group, preferably a C ₆ to C ₃₀ aryl group, more preferably a C ₆ to C ₁₈ aryl group such as phenyl, biphenyl, terphenyl, naphthyl , Phenanthrene, pyrene, and the like.

Preferably, when Ar ¹ is a C ₆ to C ₃₀ aryl group, R ^a1 , R ^b1 , R ^a2 and R ^b2 independently of _one another are a C ₁ to C ₁₀ alkyl group or a C ₆ to C ₂₀ aryl group , R ^a1 and R ^b1 and / or R ^a2 and R ^b2 may be bonded to each other to form a C ₆ to C ₂₁ ring containing a benzene ring.

More preferably, when Ar ¹ is a C ₆ to C ₁₈ aryl group, R ^a1 , R ^b1 , R ^a2 and R ^b2 independently of _one another are a C ₁ to C ₄ alkyl group or a C ₆ to C ₁₈ aryl group Or R ^a1 and R ^b1 and / or R ^a2 and R ^b2 may combine with each other to form a C ₆ -C ₁₃ ring containing a benzene ring.

Also, preferably, when Ar ¹ is an aryl group of C ₆ to C ₃₀ , R ¹ to R ⁷ independently of each other are adjacent to each other to form a C ₆ to C ₂₀ ring containing a benzene ring And more preferably, when Ar ¹ is a C ₆ to C ₁₈ aryl group, at least one pair of adjacent groups of R ¹ to R ⁷ are bonded to each other to form a C ₆ to C ₁₂ aromatic hydrocarbon containing a benzene ring .

R ^a1 , R ^b1 , R ^a2 and R ^b2 are independently of each other a C ₁ to C ₁₀ alkyl group or a C ₆ to C ₂₀ aryl group when R ¹ is a C ₆ to C ₃₀ aryl group, Or R ^a1 and R ^b1 and / or R ^a2 and R ^b2 may combine with each other to form a C ₆ to C ₂₁ ring containing a benzene ring, and R ¹ to R ⁷ may form, independently of each other, And may be bonded to each other to form a C ₆ to C ₂₀ ring containing a benzene ring.

More preferably, when Ar ¹ is a C ₆ to C ₁₈ aryl group, R ^a1 , R ^b1 , R ^a2 and R ^b2 independently of _one another are a C ₁ to C ₄ alkyl group or a C ₆ to C ₁₈ aryl group Or R ^a1 and R ^b1 and / or R ^a2 and R ^b2 may be bonded to each other to form a C ₆ to C ₁₃ ring containing a benzene ring, and at least one of R ¹ to R ⁷ adjacent groups And may be bonded to each other to form a C ₆ to C ₁₂ aromatic hydrocarbon containing a benzene ring.

For example, R ^a1 , R ^b1 , R ^a2 and R ^b2 are each independently a methyl group or a phenyl group, or R ^a1 and R ^b1 and / or R ^a2 and R ^b2 are bonded to each other to form fluorene, and R ¹ to R ⁷ At least a pair of adjacent groups may be bonded to each other to form a benzene ring, and Ar ¹ may be phenyl, biphenyl, terphenyl, naphthyl, phenanthrene or pyrene.

L 'is a single bond; An arylene group having ₆ to ₆₀ carbon atoms; A fluorenylene group; A fused ring group of an aliphatic ring of C ₃ to C ₆₀ and an aromatic ring of C ₆ to C ₆₀ ; And a C ₂ to C ₆₀ heterocyclic group.

Wherein R 'and R "are independently selected from C ₆ ~ aryl group of C ₆₀ to each other; fluorene group; C ₃ ~ fused ring group of an aromatic ring of C ₆₀ of aliphatic rings and C ₆ ~ C _60; and O, N, A C ₂ to C ₆₀ heterocyclic group containing at least one heteroatom selected from S, Si and P;

A ring formed by combining R ^a1 , R ^b1 , R ^a2 , R ^b2 , R ¹ to R ⁷ , Ar ¹ , L ', R', R ", R ^a1 and R ^b1 or R ^a2 and R ^b2 , And a ring formed by bonding adjacent groups of R ¹ to R ⁷ to each other are each a group selected from the group consisting of deuterium, halogen, a silyl group substituted or unsubstituted with a C ₁ -C ₂₀ alkyl group or a C ₆ -C ₂₀ aryl group; boron group; germanium group; a cyano group; a nitro group; a C ₁ -C ₂₀ alkylthio come; alkyl group of _{C 1 -C 20;; C 1} -C 20 alkoxyl group of the alkenyl group of C ₂ -C _20; C ₂ alkynyl of -C _20; an aryl group of C ₆ -C ₂₀ substituted with heavy hydrogen;; an aryl group of C ₆ -C ₂₀ fluorenyl group; O, N, S, at least one selected from the group consisting of Si and P of A C ₂ -C ₂₀ heterocyclic group containing a heteroatom, a C ₃ -C ₂₀ cycloalkyl group, a C ₇ -C ₂₀ arylalkyl group, and a C ₈ -C ₂₀ arylalkenyl group, Or more substituents.

For example, Ar ¹ may be further substituted with aryl groups such as phenyl, biphenyl, terphenyl, naphthyl, etc., or deuterium, methyl, ethene, methoxy, F, CN,

(1) is represented by one of the following Chemical Formulas (2) to (4):

   &Lt; Formula 2 > < EMI ID =

In the above Chemical Formulas 2 to 4, symbols such as R ¹ to R ⁷ , a, b, c, d, e, f, g and Ar ¹ are the same as defined in the above Chemical Formula 1.

Illustratively, the compound represented by Formula 1 may be one of the following compounds.

Preferably, the compound represented by the general formula (1) may be contained in the luminescent auxiliary layer in the form of a single compound or a mixture of two or more kinds, more preferably as a material of the luminescent auxiliary layer of the luminescent auxiliary layer .

According to another aspect of the present invention, there is provided an electronic device including a display device including an organic electroluminescent device, and a control unit for driving the display device, wherein the organic electroluminescent device comprises: &Lt; / RTI &gt;

Hereinafter, the synthesis examples of the compound represented by the formula according to the present invention and the production example of the organic field element will be specifically described with reference to examples, but the present invention is not limited to the following examples.

Synthetic example

The compound represented by Formula 1 according to the present invention is prepared by reacting Sub 1 and Sub 2 as shown in Reaction Scheme 1 below, but is not limited thereto.

<Reaction Scheme 1>

I. Synthesis of Sub 1

Sub 1 of Reaction Scheme 1 can be synthesized by the reaction path of Reaction Scheme 2, but is not limited thereto.

<Reaction Scheme 2>

1. Sub 1-1 Synthesis Example

4-yl) amine (25.99 g, 40.0 mmol), 1-bromo-3-chlorobenzene (8.04 g, 42.0 mmol), Pd ₂ (dba) ₃ (T-Bu) ₃ (1.2 mL, 2.4 mmol), NaO (t-Bu) (11.53 g, 120.0 mmol) and Toluene (130 mL) At reflux for 8 hours. When the reaction is complete, dilute with distilled water at room temperature and extract with toluene and water. Subsequently, the organic layer was dried over MgSO ₄ and concentrated. The resulting compound was recrystallized from toluene and acetone to obtain the product Sub 1-1 (18.25 g, 60%).

2. Sub 1-2 Synthesis Example

Bromo-3-chlorobenzene (8.04 g, 40.0 mmol) was added to a solution of 1-bromo-3-chlorobenzene (21.03 g, 40.0 mmol) (T-Bu) ₃ (1.2 mL, 2.4 mmol), NaO (t-Bu) (11.53 g, 120.0 mmol), Pd ₂ (dba) ₃ (1.10 g, 1.2 mmol) (130.2 mL), the product Sub 1-2 (15.27 g, 60%) was obtained by the same synthetic method as in the Sub 1-1 Synthesis Example.

3. Sub 1-7 Synthetic Example

Bromo-3-chlorobenzene (8.04 g, 40.0 mmol), N- (9,9-diphenyl-9H-fluoren-4-yl) -9,9'-spirobi [fluorene] (T-Bu) ₃ (1.2 mL, 2.4 mmol), NaO (t-Bu) (11.53 g, 120.0 mmol), Pd ₂ (dba) ₃ (1.10 g, 1.2 mmol) (130 mL), the product Sub 1-7 (18.20 g, 60%) was obtained by a synthetic method as in the Sub 1-1 Synthesis Example.

4. Sub 1-12 Synthesis Example

3-amine (16.06 g, 40.0 mmol), 1-bromo-3-chlorobenzene (8.04 g, 40.0 mmol), N- (9,9-dimethyl- 9H- fluoren- (T-Bu) ₃ (1.2 mL, 2.4 mmol), NaO (t-Bu) (11.53 g, 120.0 mmol), Pd ₂ (dba) ₃ (1.10 g, 1.2 mmol) (130 mL), the product Sub 1-12 (12.29 g, 60%) was obtained by the same synthetic method as in the Sub 1-1 Synthesis Example.

5. Sub 1-20 Synthetic Example

Bromo-3-chlorobenzene (8.04 g, 40.0 mmol) was added to a solution of 1-bromo-3-chlorobenzene (21.03 g, 40.0 mmol) (T-Bu) ₃ (1.2 mL, 2.4 mmol), NaO (t-Bu) (11.53 g, 120.0 mmol), Pd ₂ (dba) ₃ (1.10 g, 1.2 mmol) (130.2 mL), the product Sub 1-20 (15.27 g, 60%) was obtained by a synthetic method as in the Sub 1-1 Synthesis Example.

6. Sub 1-53 Synthetic Example

1-bromo-3-chlorobenzene (8.04 g, 40.0 mmol) was added to a solution of 1- (4-fluorophenyl) (T-Bu) ₃ (1.2 mL, 2.4 mmol), NaO (t-Bu) (11.53 g, 120.0 mmol), Pd ₂ (dba) ₃ (1.10 g, 1.2 mmol) (130 mL), the product Sub 1-53 (15.27 g, 60%) was obtained by the same synthetic method as in the Sub 1-1 Synthesis Example.

7. Sub 1-68 Synthetic Example

1-bromo-3-chlorobenzene (8.04 g, 40.0 mmol) was added to a solution of N- (9,9-diphenyl-9H-fluoren- (T-Bu) ₃ (1.2 mL, 2.4 mmol), NaO (t-Bu) (11.53 g, 120.0 mmol), Pd ₂ (dba) ₃ (1.10 g, 1.2 mmol) (130 mL), the product Sub 1-68 (15.21 g, 50%) was obtained by the same synthetic method as in the Sub 1-1 Synthesis Example.

8. Sub 1-75 Synthetic Example

3-bromo-5-chloro-1,1-diphenyl-9H-fluorene-1-amine (21.03 g, 40.0 mmol) (1.24 g, 42.0 mmol), Pd ₂ (dba) ₃ (1.10 g, 1.2 mmol), 50% P (t-Bu) ₃ (1.2 mL, 2.4 mmol), NaO g, 120.0 mmol) and Toluene (130 mL), the product Sub 1-75 (17.10 g, 60%) was obtained in the same manner as in the Sub 1-1 Synthesis Example.

The compound belonging to Sub 1 produced by the above synthesis method may be the following compound, but is not limited thereto, and Table 1 shows the FD-MS value of the compound belonging to Sub 1.

[Table 1]

Ⅱ. Example of Sub 2

The compounds belonging to Sub 2 may be, but not limited to, the following compounds, and Table 2 shows FD-MS values of the compounds belonging to Sub 2.

[Table 2]

III. Product synthesis

1. Synthesis Example of Compound P-1

Sub-1-1 (18.25 g, 24.0 mmol), Sub 2-1 (6.22 g, 24.0 mmol), Pd ₂ (dba) ₃ (0.66 g, 0.7 mmol) and P (t-Bu) ₃ 0.7 mL, 1.4 mmol), NaO (t-Bu) (6.92 g, 72.0 mmol) and Toluene (80 mL) were added thereto and the mixture was refluxed at 135 ° C for 8 hours. When the reaction is complete, dilute with distilled water at room temperature and extract with toluene and water. Then, the organic layer was dried with MgSO ₄ and concentrated. The resulting compound was dissolved in toluene. Then, the solution in toluene was passed through a silica filter and then concentrated. Subsequently, the product was recrystallized from toluene and Acetone to obtain 17.7 g , 70%).

2. Synthesis Example of Compound P-3

Sub 1-2 (18.25 g, 24.0 mmol ), Sub 2-1 (6.22 g, 24.0 mmol), Pd 2 (dba) 3 (0.66 g, 0.7 mmol), P (t-Bu) 3 (0.7 mL, 1.4 The product P-3 (16.83 g, 75%) was obtained by synthesizing the compound P-1 using the above-mentioned synthesis example P-1, using NaO (t-Bu) (6.92 g, 72.0 mmol) and Toluene .

3. Synthesis Example of Compound P-11

Sub 1-7 (18.20 g, 24.0 mmol ), Sub 2-11 (8.05 g, 24.0 mmol), Pd 2 (dba) 3 (0.66 g, 0.7 mmol), P (t-Bu) 3 (0.7 mL, 1.4 The product P-11 (17.76 g, 70%) was obtained by synthesizing the compound P-1 as described in Synthesis Example P-1, using NaO (t-Bu) (6.92 g, 72.0 mmol) and Toluene .

4. Synthesis Example of Compound P-19

Sub 1-12 (12.29 g, 24.0 mmol ), Sub 2-28 (6.34 g, 24.0 mmol), Pd 2 (dba) 3 (0.66 g, 0.7 mmol), P (t-Bu) 3 (0.7 mL, 1.4 The product P-19 (10.66 g, 60%) was obtained by synthesizing the compound P-1 using the above-mentioned synthesis example P-1, using NaO (t-Bu) (6.92 g, 72.0 mmol) and Toluene .

5. Synthesis Example of Compound P-28

Sub 1-20 (15.27 g, 24.0 mmol ), Sub 2-4 (8.05 g, 24.0 mmol), Pd 2 (dba) 3 (0.66 g, 0.7 mmol), P (t-Bu) 3 (0.7 mL, 1.4 The product P-28 (13.47 g, 60%) was obtained by synthesizing the compound P-1 using the above-mentioned synthesis example P-1, using NaO (t-Bu) (6.92 g, 72.0 mmol) and Toluene .

6. Compound P-72 Synthesis Example

Sub 1-53 (15.27 g, 24.0 mmol ), Sub 2-29 (9.25 g, 24.0 mmol), Pd 2 (dba) 3 (0.66 g, 0.7 mmol), P (t-Bu) 3 (0.7 mL, 1.4 The product P-72 (11.82 g, 50%) was obtained by synthesizing the compound P-1 using the above-mentioned synthesis example P-1, using NaO (t-Bu) (6.92 g, 72.0 mmol) and Toluene .

7. Compound P-94 Synthesis Example

P (t-Bu) ₃ (0.6 mL, 1.2 mmol), Sub 2-2 (6.71 g, 20.0 mmol), Pd ₂ (dba) ₃ (0.55 g, 0.6 mmol) The product P-94 (14.83 g, 70%) was obtained by synthesizing the compound P-1 using the above-mentioned synthesis example P-1, using NaO (t-Bu) (5.77 g, 60.0 mmol) and Toluene .

8. Compound P-103 Synthesis Example

Sub 1-75 (17.10 g, 24.0 mmol ), Sub 2-3 (8.05 g, 24.0 mmol), Pd 2 (dba) 3 (0.66 g, 0.7 mmol), P (t-Bu) 3 (0.7 mL, 1.4 The product P-103 (13.35 g, 55%) was obtained by synthesizing the compound P-1 using the above-mentioned synthesis example P-1, using NaO (t-Bu) (6.92 g, 72.0 mmol) and Toluene .

The FD-MS values of the compounds P-1 to P-108 of the present invention prepared according to the above synthesis examples are shown in Table 3 below.

[Table 3]

Evaluation of Manufacture of Organic Electroluminescent Device

[Example 1] Green organic electroluminescent device (luminescent auxiliary layer)

N ¹ on the ITO layer (anode) formed on the glass substrate - (naphthalen-2-yl) -N 4, N 4 -bis (4- (naphthalen-2-yl (phenyl) amino) phenyl) -N 1 -phenylbenzene -1,4-diamine (hereinafter abbreviated as "2-TNATA") was vacuum-deposited to form a hole injection layer having a thickness of 60 nm, and then N, N'-bis (1-naphthalenyl) bis-phenyl- (1,1'-biphenyl) -4,4'-diamine (hereinafter abbreviated as "NPB") was vacuum-deposited to a thickness of 60 nm to form a hole transport layer. next,

Next, Compound P-1 of the present invention was vacuum deposited on the hole transport layer to a thickness of 20 nm to form a light-emission-assisting layer.

Next, 4,4'-N, N'-dicarbazole-biphenyl (hereinafter referred to as "CBP") was used as a host material and tris (2-phenylpyridine) -iridium Quot; Ir (ppy) ₃ &quot;) was used in a weight ratio of 95: 5 to form a light emitting layer with a thickness of 30 nm.

Subsequently, aluminum (1,1'-biphenyl-4-olato) bis (2-methyl-8-quinolinolato) aluminum (abbreviated as "BAlq" hereinafter) was vacuum deposited as a hole blocking layer on the light emitting layer to a thickness of 10 nm Tris- (8-hydroxyquinoline) aluminum (hereinafter abbreviated as " Alq ₃ &quot;) was vacuum deposited as an electron transport layer on the hole blocking layer to a thickness of 40 nm. Thereafter, LiF, an alkali metal halide serving as an electron injecting layer, was deposited to a thickness of 0.2 nm, and then Al was deposited to a thickness of 150 nm to form a cathode.

[Examples 2 to 31]

An organic electroluminescence device was prepared in the same manner as in Example 1, except that the compound of the present invention described in Table 4 was used instead of the compound P-1 of the present invention as a material of the luminescent auxiliary layer.

[ Comparative Example  One]

An organic electroluminescence device was fabricated in the same manner as in Example 1 except that no luminescent auxiliary layer was formed.

[Comparative Example 2] to [Comparative Example 5]

An organic electroluminescence device was prepared in the same manner as in Example 1, except that one of the following Comparative Compounds A to D was used in place of the compound P-1 of the present invention as a material of the luminescent auxiliary layer.

[Comparative Example 6]

An organic electroluminescent device was prepared in the same manner as in Example 1 except that the compound P-1 of the present invention was used as a material of the hole transport layer and NPB was used as a material of the luminescent auxiliary layer.

<Comparative Compound A> <Comparative Compound B> <Comparative Compound C> <Comparative Compound D>

Electruminescence (EL) characteristics were measured with photoresearch PR-650 by applying a forward bias DC voltage to the organic EL devices manufactured in Examples 1 to 21 and Comparative Examples 1 to 6 of the present invention Was measured at a luminance of 5000 cd / m &lt; ² &gt; through a life measuring apparatus manufactured by Mac Science Inc., and T95 lifetime was measured.

[Table 4]

As can be seen from the results of Table 4, when a green organic electroluminescent device was manufactured using the material for an organic electroluminescent device of the present invention as a light emitting auxiliary layer material, D, the driving voltage of the organic electroluminescent device can be lowered, as well as the luminescent efficiency and lifetime can be improved.

The driving voltage, the efficiency and the lifetime were improved in Comparative Examples 2 to 5 in which the light-emission-assisting layer was formed using one of the comparative compounds A to D rather than the comparative example 1 in which the luminescent auxiliary layer was not formed. In the embodiments of the present invention using NPB as the hole transporting layer material and the compound of the present invention as the light emitting auxiliary layer material, the driving voltage, the efficiency, and the life span were significantly improved compared with Comparative Examples 1 to 5.

Comparative Compound A and Comparative Compound B differ only in the position where the amine group is bonded to dibenzofurane. In Comparative Compound A, the amine group is bonded to the 1-position of dibenzofurane, and the comparative compound B is the amine group Is bonded to the 4-position of dibenzofurane. The device characteristics of Comparative Example 2 and Comparative Example 3 using these compounds as the light emitting auxiliary layer material were better than those of Comparative Example 3.

Further, when comparing the comparative compound B with the comparative compound C, only the positions at which both amines are bonded to the phenyl are different. In the comparative compound B, both amine groups are linearly positioned (that is, an amine group is bonded at the para position of phenyl ), Whereas Comparative Compound C differs in that both amine groups are in a non-linear position (i.e., the amine group is bonded to the meta position of the phenyl). The device characteristics of Comparative Example 3 and Comparative Example 4 using these compounds as the light emitting auxiliary layer material were remarkably improved in Comparative Example 4 using Comparative Compound C.

Further, when comparing the comparative compound C with the comparative compound D, the comparative compound C has phenyl bonded to the nitrogen of the amine group bonded with the dibenzofuran, while the comparative compound D has the dimethylfluorene bonded thereto. The device characteristics of Comparative Example 4 and Comparative Example 5 using these compounds as the light-emitting auxiliary layer material were slightly improved in the device characteristics of Comparative Example 5.

Therefore, from the results of the device characteristics of Comparative Examples 2 to 5, it can be seen that when two amine groups are bonded to a linker in the form of a linker, they are bound to the linker in a meta position and fluorine, which is the same substituent, It can be seen that the characteristics of the organic electroluminescent device can be improved when the compound having a hole transporting property is used as a light emitting auxiliary layer material.

From these results, it can be seen that the characteristics of the device can be varied depending on the substitution position of the substituent, the kind of the substituent, and the like. It seems that the physical properties of the compound during compound deposition in the manufacturing process act as a major factor (eg, energy balance) in improving the device performance.

Meanwhile, in the compound of Chemical Formula 1 of the present invention, two amine groups are substituted at the meta position of the phenyl which is a linking group, 4-dibenzofuran is bonded to the nitrogen of one of the amine groups, and nitrogen of the other amine group And two fluorenes are bonded to each other.

As can be seen from the above-described Comparative Example 4 and Comparative Example 5, when two amine groups are bonded to the core of 4-dibenzofurane, two fluorene groups It was confirmed that the device characteristics of the compound were further improved. As in the case of Comparative Example 5 of the present invention, it was confirmed that the compound containing two fluorenes in the compound but not the fluorenes bonded to the nitrogen of the different amine groups, There is a difference in that fluorine is bonded to each nitrogen. However, as can be seen from the above Table 4, the compound of the present invention in which two fluorenes are bonded to one amine group is used as a light emitting auxiliary layer material, compared with Comparative Example 5 in which fluorene is bonded to nitrogen of both amine groups The characteristics of the device were remarkably improved.

This is because the physical properties of compounds including LUMO, HOMO, band gab and T 1 value are different depending on whether the two fluorenes are bonded to the nitrogen of the amine group or the amine group, respectively. The difference in physical properties seems to be a major factor affecting the device characteristics during compound deposition for forming the luminescent auxiliary layer in the device manufacturing process.

Therefore, even if a compound having a similar structure, it can be seen that a slight difference in the type and position of a substituent plays a decisive role in the difference in physical properties, so that a device characteristic result that is difficult for a typical technician to easily obtain can be derived. Comparing the embodiments of the present invention, it can be seen that even when the same compound is used, completely different device characteristic results can be obtained depending on which layer is used for which layer, that is, the combination of materials used in each layer.

The foregoing description is merely illustrative of the present invention, and various modifications may be made without departing from the essential characteristics of the present invention. Accordingly, the embodiments disclosed herein are intended to be illustrative rather than limiting, and the spirit and scope of the present invention is not limited by these embodiments. The scope of protection of the present invention should be construed according to the following claims, and all the techniques within the scope of the present invention should be construed as being included in the scope of the present invention.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation-in-part of U.S. Patent Application No. 119-121, 365 (35 USC §§19 to §121, §365 ), The entire contents of which are incorporated herein by reference. In addition, the present patent application is also incorporated in the present patent application as a reference, if the priority is given to the countries other than the US for the same reason as above.

Claims (8)

An organic electroluminescent device comprising a first electrode, a second electrode, and an organic layer formed between the first electrode and the second electrode, Wherein the organic material layer includes a light emitting auxiliary layer formed between the first electrode and the light emitting layer, and the light emitting auxiliary layer includes a compound represented by the following general formula (1): &lt; EMI ID = &Lt; Formula 1 >

In Formula 1, R ^a1 , R ^b1 , R ^a2 and R ^b2 are each independently a C ₁ to C ₅₀ alkyl group; A C ₆ to C ₆₀ aryl group; A fluorenyl group; And a C ₂ to C ₆₀ heterocyclic group containing at least one hetero atom selected from O, N, S, Si and P; R ^a1 and R ^b1 are bonded to each other or R ^a2 and R ^b2 are bonded to each other to form a C ₆ to C ₆₀ aromatic hydrocarbon; A fluorenyl group; A C ₂ to C ₆₀ heterocyclic group containing at least one heteroatom selected from O, N, S, Si and P; A C ₃ to C ₆₀ aliphatic ring; Or fused ring group of an aromatic ring of C ₃ ~ C ₆₀ of aliphatic rings and C ₆ ~ C _60; may form a, R ¹ to R ⁷ independently from each other are hydrogen; heavy hydrogen; halogen; A C ₆ to C ₆₀ aryl group; A fluorenyl group; A C ₂ to C ₆₀ heterocyclic group containing at least one heteroatom selected from O, N, S, Si and P; A fused ring group of an aliphatic ring of C ₃ to C ₆₀ and an aromatic ring of C ₆ to C ₆₀ ; A C ₁ to C ₅₀ alkyl group; An alkenyl group having ₂ to ₂₀ carbon atoms; An alkynyl group having ₂ to ₂₀ carbon atoms; A C ₁ to C ₃₀ alkoxyl group; An aryloxy group of C ₆ to C ₃₀ ; (R ') (R "), and adjacent groups are bonded to each other to form a C ₆ to C ₆₀ aromatic hydrocarbon, a fluorenyl group, O, N, S, Si and at least one hetero atom heterocyclic group of C ₂ ~ C ₆₀ containing from P; C ₃ ~ C ₆₀ of aliphatic ring; or a C ₃ ~ C ₆₀ alicyclic and C ₆ ~ fused ring of an aromatic ring of C ₆₀ May form a group, a, c, e and g are each an integer of 0 to 4, b, d and f are each an integer of 0 to 3, Ar ¹ is a C ₆ to C ₆₀ aryl group, L 'is a single bond; An arylene group having ₆ to ₆₀ carbon atoms; A fluorenylene group; A fused ring group of an aliphatic ring of C ₃ to C ₆₀ and an aromatic ring of C ₆ to C ₆₀ ; And a C ₂ to C ₆₀ heterocyclic group, Wherein R 'and R "are independently selected from C ₆ ~ aryl group of C ₆₀ to each other; fluorene group; C ₃ ~ fused ring group of an aromatic ring of C ₆₀ of aliphatic rings and C ₆ ~ C _60; and O, N, A C ₂ to C ₆₀ heterocyclic group containing at least one hetero atom selected from the group consisting of S, Si and P; A ring formed by combining R ^a1 , R ^b1 , R ^a2 , R ^b2 , R ¹ to R ⁷ , Ar ¹ , L ', R', R ", R ^a1 and R ^b1 or R ^a2 and R ^b2 , And a ring formed by bonding adjacent groups of R ¹ to R ⁷ to each other are each a group selected from the group consisting of deuterium, halogen, a silyl group substituted or unsubstituted with a C ₁ -C ₂₀ alkyl group or a C ₆ -C ₂₀ aryl group; boron group; germanium group; a cyano group; a nitro group; a C ₁ -C ₂₀ alkylthio come; alkyl group of _{C 1 -C 20;; C 1} -C 20 alkoxyl group of the alkenyl group of C ₂ -C _20; C ₂ alkynyl of -C _20; an aryl group of C ₆ -C ₂₀ substituted with heavy hydrogen;; an aryl group of C ₆ -C ₂₀ fluorenyl group; O, N, S, at least one selected from the group consisting of Si and P of A C ₂ -C ₂₀ heterocyclic group containing a heteroatom, a C ₃ -C ₂₀ cycloalkyl group, a C ₇ -C ₂₀ arylalkyl group, and a C ₈ -C ₂₀ arylalkenyl group, Or more substituents. The method according to claim 1, (1) is represented by one of the following Chemical Formulas (2) to (4):    &Lt; Formula 2 > < EMI ID =

In the above Chemical Formulas 2 to 4, Ar ¹ , R ¹ to R ⁷ , a, b, c, d, e, f and g are as defined in claim 1. The method according to claim 1, The organic electroluminescent device according to claim 1, wherein the compound represented by Formula 1 is one of the following compounds:

. The method according to claim 1, The organic electroluminescent device according to claim 1, wherein the compound represented by the formula (1) is contained in the luminescent auxiliary layer in the form of a single compound or a mixture of two or more compounds. The method according to claim 1, Wherein the compound is used as a material of the green light emission assisting layer of the light emission-assisting layer. The method according to claim 1, Wherein the organic material layer is formed by a spin coating process, a nozzle printing process, an inkjet printing process, a slot coating process, a dip coating process or a roll-to-roll process. A display device comprising the organic electroluminescent device of claim 1; And And a control unit for driving the display device. 8. The method of claim 7, Wherein the organic electroluminescent device is selected from the group consisting of an organic electroluminescent device, an organic solar cell, an organophotoreceptor, an organic transistor, a monochromatic illumination device, and a quantum dot display device.

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