KR20080111968A - Electroluminescent polymers containing fluorine functional groups and organic electroluminescent device manufactured using the same - Google Patents

Abstract

An electroluminescent polymer containing a fluorine functional group is provided to ensure high luminous efficiency and excellent solubility and to realize excellent light-emitting property in use as a host material of blue, red and green. An electroluminescent polymer is represented by the chemical formula 1 or the chemical formula 2. In the formulae, R1 and R2 are the same or different and represent F and an aryl group substituted or non- substituted with at least one substituent selected from the group consisting of C1-20 linear or branched alkyl group and alkoxy group containing F; R3 is an R3 is the alkyl group of the straight-chain of the carbon number 1~20 or the branching chain and alkoxy radical; Ar1 is an aryl amine group substituted or non- substituted with at least one substituent selected from the group consisting of C1-20 linear or branched alkyl group and alkoxy group; Ar2 is a substituted or non-substituted C6~C60 aromatic compound, substituted or non-substituted C2~C60 heteroaromatic compound and their combination; X is an integer of 1~10,000; Y is an integer of 0~10,000; and Z is an integer of 1~100,000.

Description

Electroluminescent polymer containing fluorine group and electroluminescent device using the same {Electroluminescent polymers containing fluorine functional groups and organic electroluminescent device manufactured using the same}

1 is a cross-sectional view showing a structure of a general organic electroluminescent device manufactured from a substrate / anode / hole transport layer / light emitting layer / electron transport layer / cathode.

2 is a view showing the synthesis reaction overview of the monomer for the electro-molecules represented by M1, M2 and M3 of the present invention.

Figure 3 is a view showing the synthesis reaction overview of the monomer for electroadhesive molecules represented by MF1 of the present invention.

4 is a view showing the synthesis reaction overview of the monomer for the electro-adhesive molecule represented by MF6 of the present invention.

5 is a diagram showing a monomer according to a substituent synthesized by the synthesis reaction of FIGS.

※ Explanation of code about main part of drawing ※

11 substrate 12 anode

13 hole transport layer 14 light emitting layer

15: electron transport layer 16: cathode

The present invention relates to an electroluminescence molecule comprising a fluorine group and an electroluminescence device using the same, and more particularly, to intermolecular interaction with an aryl skeleton capable of high luminous efficiency and hole transport function. And an organic electroluminescent molecule and an electroluminescent device using the same, having excellent thermal stability and high luminous efficiency, and excellent solubility and minimizing intermolecular interaction by substituting a substituent large enough to suppress an excimer. It is about.

Recently, due to the rapid growth of the optical communication and multimedia fields, the development into a highly information society has been accelerated. Accordingly, optoelectronic devices using the conversion of photons to electrons or the conversion of electrons to photons have become the core of the modern information electronics industry. Such semiconductor optoelectronic devices can be broadly classified into electroluminescent devices, light receiving devices, and devices in which they are combined.

Until now, most displays are light-receiving, while self-emissive electroluminescence displays are fast response and self-emissive, so they don't need backlighting and have excellent brightness. It is attracting attention as a display element. Such electroluminescent devices are classified into inorganic and organic light emitting devices according to materials for forming a light emitting layer.

Organic electroluminescence (EL) is a phenomenon in which when an electric field is applied to an organic material, electrons and holes are transferred from the cathode and the anode, respectively, to be combined within the material, and the energy generated is emitted as light. The electroluminescence of these organic materials was reported by Pope et al. In 1963, and in 1987 by Tang et al. At Eastmann Kodak, alumina-quinone. Many studies have been conducted since a light emitting device having a multi-layered structure having a quantum efficiency of 1% and a luminance of 1000 cd / m 2 at 10V or less as a device manufactured from a pigment having a π-conjugated structure. They have the advantage of easy synthesis and synthesis of various types of materials and simple color tuning. However, when workability or thermal stability is low and voltage is applied, Joule heat is generated in the light emitting layer, and as the molecules are rearranged, the device is destroyed and causes problems in luminous efficiency or life of the device. Substitution is progressing with the organic electroluminescent element which has.

In this regard, FIG. 1 shows a structure of a general organic electroluminescent device made of a substrate / anode / hole transport layer / light emitting layer / electron transport layer / cathode. Referring to FIG. 1, an anode 12 is formed on the substrate 11. The hole transport layer 13, the light emitting layer 14, the electron transport layer 15, and the cathode 16 are sequentially formed on the anode 12. Here, the hole transport layer 13, the light emitting layer 14, and the electron transport layer 15 are organic thin films made of an organic compound. The driving principle of the organic electroluminescent device of the above structure is as follows:

When a voltage is applied between the anode 12 and the cathode 16, holes injected from the anode 12 are moved to the light emitting layer 14 via the hole transport layer 13. On the other hand, electrons are injected into the light emitting layer 14 from the cathode 16 via the electron transport layer 15, and carriers are recombined in the light emitting layer 14 to generate excitons. This exciton is changed from the excited state to the ground state, whereby the fluorescent molecules of the light emitting layer emit light to form an image. The organic electroluminescent device driven on the principle described above is classified into a polymer organic electroluminescent device and a low molecular organic electroluminescent device according to the molecular weight of the material for forming an organic film.

In general, in the case of using a low molecule in forming the organic film, the low molecule is easy to purify and can almost eliminate impurities, and excellent in luminescence properties. However, there is a problem in that inkjet printing or spin coating is impossible and heat resistance is poor, thereby deteriorating or recrystallization by driving heat generated when driving the device. On the other hand, when the polymer is used to form the organic film, the energy level is separated into the conduction band and the electrical appliance diagram by the superposition of the π-electron wave function in the polymer backbone, and the band gap energy corresponding to the energy difference is used. The semiconducting properties of the polymer are determined and full color can be achieved. Such polymers are called π-conjugated polymers.

An electroluminescent device using poly (p-phenylenevinylene) (PPV), a polymer having conjugated double bonds, was first introduced in 1990 by a team of professors from RH Friend at the University of Cambridge, UK. After being announced, researches using organic polymers have been actively conducted. The polymer has excellent heat resistance compared to the low molecule, and inkjet printing and spin coating are possible, which makes it easy to increase the size of the display device. By introducing various suitable substituents, polyphenylenevinylene (PPV) derivatives, polythiophene (Pth) derivatives, and the like, which can improve processability and express various colors, have been reported. However, as materials such as polyphenylenevinylene derivatives and polythiophene derivatives, high efficiency red and green light emitting polymer materials can be obtained among the three primary colors of light, but high efficiency blue light emitting polymer materials can be obtained. it's difficult. In addition, polyphenylene derivatives, polyfluorene derivatives, and the like have been reported as blue light emitting polymer materials. Polyphenylene has high oxidation stability and thermal stability, but has a disadvantage of low luminous efficiency and poor solubility.

With respect to the polyfluorene derivatives, the prior art is as follows:

US Pat. No. 6,255,449 discloses 9-substituted-2,7-dihalofluorene compounds, and oligomers and polymers thereof, suitable as light emitting materials, such as light emitting layers or carrier transport layers of light emitting diodes.

US Patent Nos. 6,309,763 and 6,605,373 introduce electroluminescent copolymers containing florin groups and amine groups in repeat units. According to the '763 patent, such a copolymer is useful as a light emitting layer or a hole transporting layer of an electroluminescent device.

On the other hand, US Patent No. 6,630,566 discloses a polymer comprising N, P, S, AS or SE useful as a light emitting polymer, specifically, a polymer containing a triarylamine repeat unit, US Patent No. 6,887,973 is an anion Electroluminescent polymers are disclosed that contain fluorene or phenylene repeat units and triarylamine units such that the transporter and cation transporter are in one molecule and the first and second bandgaps of different properties are present. . In addition, Japanese Patent Laid-Open No. 2003-00199203 discloses an arylamine derivative having a fluorene skeleton.

As described above, researches using polyfluorene derivatives as active blue molecules have been actively conducted. However, minimization of interaction between excitons produced in one molecule and excitons in other molecules, and improvement of injection and transport properties of holes and electrons It has problems such as efficiency improvement, color purity and lifetime improvement.

Therefore, in the present invention, as a result of extensive research to solve the above problems, it has excellent solubility and minimizes intermolecular interactions and has a high luminous efficiency, the hole of the conventional polyfluorene-based (PFs) Electron adsorption molecules using new aryl derivatives and special electroluminescent devices using the same aryl derivatives, which have significantly improved injection and transfer properties, color purity and luminous efficiency, have been discovered.

Therefore, an object of the present invention is an organic electroluminescent polymer which is required to realize high efficiency blue, green and red light emitting polymers by minimizing intermolecular interactions and easy energy transfer, improving hole injection and transporting properties. To provide.

Another object of the present invention to provide an electroluminescent device manufactured using the electro-molecular advertising molecules.

In order to achieve the above object, the organic electro-molecule advertisement molecule according to the present invention is characterized in that the organic electro-molecule advertisement molecule represented by the following Formula 1 or Formula 2 containing a fluorine group:

Where

R ₁ and R ₂ are the same as or different from each other, F, or an aryl group which is unsubstituted or substituted with at least one substituent selected from the group consisting of a C1-C20 linear or branched alkyl group and an alkoxy group containing F; ;

R ₃ is a linear or branched alkyl group or alkoxy group having 1 to 20 carbon atoms;

Ar ₁ is an arylamine group which is unsubstituted or substituted with at least one substituent selected from the group consisting of a linear or branched alkyl group having 1 to 20 carbon atoms and an alkoxy group;

Ar ₂ is selected from the group consisting of C6-C60 substituted or unsubstituted aromatic compounds, C2-C60 substituted or unsubstituted heteroaromatic compounds, and combinations thereof; And,

x is an integer of 1-10,000, y is an integer of 0-10,000, z is an integer of 1-100,000.

An electroluminescent device according to the present invention for achieving the above another object has at least one layer comprising the organic electroluminescent molecules between the anode and the cathode, wherein the layer is a hole transport layer, a light emitting layer or an electron transport layer It is done.

Hereinafter, the present invention will be described in more detail.

As described above, in the present invention, it has excellent thermal stability and high luminous efficiency, has excellent solubility and minimizes intermolecular interactions, and provides injection and delivery properties of holes, which are disadvantages of conventional polyfluorene-based (PFs). Provided are electroluminescent molecules incorporating special structural units that significantly improve luminous efficiency, and electroluminescent devices using the same.

Organic electro-adhesive molecules according to the present invention are light emitting polymers having properties of excellent thermal stability, light stability, solubility, film formability, excellent hole injection / transfer quality, excellent color purity and high luminous efficiency, and the specific structural unit of the main chain Since it plays a role of breaking conjugation, it has excellent color purity and has the advantage of simultaneously injecting and transferring holes, which is an inherent property of arylamine, and by introducing a large substituent at the 9 position of fluorene. The encapsulation of almost planar fluorene prevents intermolecular excimers and aggregation and maximizes intramolecular or intermolecular energy transfer from shorter substituents to the main chain. Large fluorenyl groups inhibit rotation and vibration modes, greatly reducing nonradiative decay Therefore, the organic electroluminescent molecule of the present invention exhibits excellent color purity, brightness and high efficiency of light emission.

Electromolecular adsorption molecules comprising special structural units according to the invention are represented by the following general formula (1) or (2):

<Formula 1>

<Formula 2>

Where

R ₁ and R ₂ are the same as or different from each other, F, or an aryl group which is unsubstituted or substituted with at least one substituent selected from the group consisting of a straight or branched chain alkyl group having 1 to 20 carbon atoms and an alkoxy group containing F; ;

R ₃ is a linear or branched alkyl group or alkoxy group having 1 to 20 carbon atoms;

Ar ₁ is an arylamine group which is unsubstituted or substituted with at least one substituent selected from the group consisting of a linear or branched alkyl group having 1 to 20 carbon atoms and an alkoxy group;

Ar ₂ is selected from the group consisting of C6-C60 substituted or unsubstituted aromatic compounds, C2-C60 substituted or unsubstituted heteroaromatic compounds, and combinations thereof; And,

x is an integer of 1-10,000, y is an integer of 0-10,000, z is an integer of 1-100,000.

In this case, preferably, x is an integer of 1 to 10,000, y is an integer of 0 to 10,000, z is an integer of 4 to 100,000, and x / y is preferably 1/19 or more; x: (y + z) preferably has a ratio of 5:95 to 90:10.

In addition, the weight average molecular weight of the polymer represented by General formula (1) or (2) is an integer of 800-4,000,000, and molecular weight distribution is 1-10.

Preferably, R ₃ may preferably be selected from the following compounds:

R ₁ And R ₂ are the same as or different from each other, F, or an aryl group which is unsubstituted or substituted with at least one substituent selected from the group consisting of an alkyl group having 1 to 20 carbon atoms or an alkoxy group containing 1 to 20 carbon atoms;

Meanwhile, in Formula 1 or 2, Ar ₁ may be preferably selected from the following compounds:

On the other hand, Ar ₂ is preferably,

(Iii) a C6 to C60 substituted or unsubstituted arylene group;

(Ii) a C2 to C60 substituted or unsubstituted heterocyclic arylene group wherein at least one hetero atom selected from the group consisting of N, S, O, P and Si is included in the aromatic ring;

(Iii) a C 6 to C 60 substituted or unsubstituted arylenevinylene group; And

(Iii) selected from the group consisting of combinations thereof

Here, Ar ₂ is a linear or branched alkyl or alkoxy group having 1 to 20 carbon atoms; An aryl group which is unsubstituted or substituted with at least one substituent selected from the group consisting of a linear or branched alkyl group having 1 to 20 carbon atoms and an alkoxy group; Cyano group (-CN); Or a substituent such as a silyl group.

More specifically,

(Iii) when Ar ₂ is a phenylene group or fluorenyl group among the substituted or unsubstituted arylene groups of C6 to C60, representative examples of such compounds are as follows, and may be selected from:

(Ii) where Ar ₂ is a C2-C60 substituted or unsubstituted heterocyclic arylene group, representative examples of such compounds are as follows and may be selected from:

(Iii) When Ar ₂ is a C ₆ to C 60 substituted or unsubstituted arylenevinylene group, representative examples of such compounds are as follows, and may be selected from them.

One of the methods for preparing the organic electro-molecular advertising molecule of the present invention is as follows. That is, after preparing monomers through alkylation reaction, bromination reaction, Grignard reaction, Wittig reaction, etc., organic electroadhesive molecules may be finally prepared through CC coupling reaction such as Yamamoto coupling reaction and Suzuki coupling reaction. Can be. The number average molecular weight of the polymers obtained therefrom is 800 to 4,000,000, and the molecular weight distribution is 1 to 10.

The organic electro-adhesive molecule according to the present invention described above emits light having the lowest band gap in the fluorene-containing fluorene portion. At this time, the fluorene group, which is a light emitting part, has excellent thermal stability, oxidation stability, high glass transition temperature, minimal intermolecular interaction, easy energy transition, and high vibration efficiency by suppressing vibration mode as much as possible. It can be applied as a host for blue, green and red light emitting.

According to the present invention, the organic electroluminescent molecule is used as a material for forming a light emitting layer, a hole transport layer or an electron transport layer located between a pair of electrodes in the electroluminescent device. The organic electroluminescent device of the present invention may be configured to further include a hole transport layer and an electron transport layer as well as the most common device configuration of the anode / light emitting layer / cathode.

1 is a cross-sectional view illustrating a structure of a general organic electroluminescent device composed of a substrate / anode / hole transport layer / light emitting layer / electron transport layer / cathode. Referring to this, an example of an organic electroluminescent device to which the organic electroluminescent molecule of the present invention is applied is as follows. It can be prepared as follows.

First, a material for the anode 12 electrode is coated on the substrate 11.

Here, the substrate 11 is a substrate used in a conventional organic electroluminescent device, preferably a glass substrate or a transparent plastic substrate excellent in transparency, surface smoothness, ease of handling and waterproof.

In addition, as the material for the anode 12 electrode, indium tin oxide (ITO), tin oxide (SnO ₂ ), zinc oxide (ZnO), or the like, which is transparent and has excellent conductivity, may be used.

Next, the hole transport layer 13 may be formed by vacuum deposition or sputtering on the anode 11 electrode, and the light emitting layer 14 may be formed through a solution coating method such as spin coating or inkjet printing. In addition, the electron transport layer 15 is formed on the light emitting layer 14 before the cathode 16 is formed. At this time, the thickness of the light emitting layer 14 is preferably 5nm ~ 1㎛, preferably 10 ~ 500nm, the thickness of the hole transport layer and the electron transport layer is preferably 10 ~ 10,0001.

According to the present invention, a material for forming an electron transport layer may be used for the electron transport layer 15, or the compound represented by Chemical Formula 1 may be formed by vacuum deposition, sputtering, spin coating, or inkjet printing.

The hole transport layer 13 and the electron transport layer 15 serves to increase the probability of light emitting coupling in the light emitting polymer by efficiently transporting the carriers to the light emitting polymer. The material for forming the hole transport layer 13 and the electron transport layer 15 usable in the present invention is not particularly limited, but preferably, the hole transport layer material is a poly (3) doped with a poly (styrenesulphonic acid) (PSS) layer. PEDOT: PSS, N, N'-bis (3-methylphenyl) -N, N-diphenyl- [1,1'-biphenyl] -4,4, which is, 4-ethylenedioxy-thiophene) (PEDOT) '-Diamine (TPD) is preferred, and the electron transport layer material is aluminum trihydroxyquinoline (Alq3), 1,3,4-oxadiazole derivative PBD (2- (4-biphenylyl) -5-phenyl -1,3,4-oxadiazole, TPQ (1,3,4-tris [(3-penyl-6-trifluoromethyl) quinoxaline-2-yl] benzene), which is a quinoxaline derivative, and a triazole derivative.

On the other hand, when the organic electro-adhesive molecule according to the present invention to form a layer through the solution coating method, by blending with polymers having conjugated double bonds, such as other fluorene-based polymers, polyphenylene vinylene-based, polyparaphenylene-based In some cases, binder resins may be mixed and used. Examples of the binder resins include polyvinylcarbazole, polycarbonate, polyester, polyarylate, polystyrene, acrylic polymer, methacryl polymer, polybutyral, polyvinyl acetal, diallyl phthalate polymer, phenol resin, epoxy resin, Silicone resins, polysulfone resins or urea resins, and the like, which may be used individually or in combination.

Optionally, a hole-blocking layer, such as lithium fluoride (LiF), is further formed by vacuum deposition or the like to limit the transfer rate of holes in the light-emitting layer 14 and to bond electron-holes. You can increase the probability.

Finally, a material for the cathode 16 electrode is coated on the electron transport layer 15.

As the cathode forming metal, lithium (Li), magnesium (Mg), calcium (Ca), barium (Ba), aluminum (Al), Al: Li, and the like having a small work function are used.

The organic electroluminescent device according to the present invention may be manufactured in the order as described above, namely anode / hole transport layer / light emitting layer / electron transport layer / cathode, and vice versa, that is, cathode / electron transport layer / light emitting layer / hole transport layer / anode You may manufacture in order.

In addition, the organic electroluminescent molecules according to the present invention can be used not only in the polymer organic electroluminescent device but also in the photoconversion material in the photodiode or in the semiconductor material organic solar cell in the polymer TFT (Thin Film Transistor).

As described above, the organic electro-adhesive molecule according to the present invention introduces a large substituent containing fluorine into the aryl derivative used as the main chain, thereby randomizing the arrangement between the main chain and the substituent by the substituent, and intermolecular excitation by the substituent. Characterization of the maximum inhibition of the cymer is expressed to inhibit aggregation and / or formation of excimers. In addition, the intramolecular or intermolecular energy transfer from the short-wave substituent to the main chain is possible, and rotational and vibrational modes are suppressed by substituted large fluorenyl groups, thereby greatly reducing non-radiative attenuation, thereby providing excellent thermal stability, light stability, and solubility. In addition to having the properties of film formability and high quantum efficiency, it has a structure that blocks the conjugation (conjugation) has a great advantage as a blue light emitting unit having excellent color purity of high efficiency. Accordingly, the organic electroluminescent molecule of the present invention and the organic electroluminescent device using the same exhibit excellent characteristics such as color purity, brightness and high luminous efficiency.

Hereinafter, the present invention will be described in more detail with reference to the following examples, but the scope of the present invention is not limited thereto. Meanwhile, the compounds mentioned as M1 to M4 below are monomers for preparing the electroadhesive molecules of the present invention, and are represented by the following structural formulas. The following specific monomers are intended to illustrate the invention and should not be construed as limiting the invention thereto.

Hereinafter, the present invention will be described in more detail with reference to the following examples, but the scope of the present invention is not limited thereto.

Preparation Example 1

-Synthesis of (9- (9,9-dihexylfluoren-2-yl) -2,7-dibromofluoren-9-ol) (IM-1)

Mg 3.3 g (137 mmol) was added to a 500 mL three neck flask at room temperature. 47.1 g (114 mmol) of 9,9-dihexyl-2-bromofluorene was dissolved in 200 mL of THF (Tetrahydrofuran). Add Grignard reagent slowly by dropping while maintaining at 65 ^o C. The temperature of the reactor was lowered to -40 ° C. or lower, and then 30 g (91 mmol) of 2,7-dibromofluorenone was added under a nitrogen stream, and the temperature was gradually raised to room temperature, followed by stirring for 10 hours. The reaction is poured into water, extracted with diethyl ether and the solvent is blown on a rotary evaporator. 45 g (67 mmol, 73%) of 9- (9,9-dihexylfluoren-2-yl) -2,7-dibromofluorene-9-ol (IM-1) isolated by column chromatography Got.

Preparation Example 2

-Synthesis of (1,2-di (2-methyl) butyloxy benzene) (IM-2)

In a 500 mL round flask, 20 g (91 mmol) of compound catechol and 107 g (436 mmol) of 2-methyl butyl p-toluenesulfonate were dissolved in 200 mL of DMSO, followed by slowly adding 53 g (473 mmol) of potassium tert-butoxide (t-BuOK) equivalent. The reaction is carried out at 70 ° C. for 12 hours. The reaction was poured into 500 mL of water, extracted using methyl chloride, and the solvent was removed by rotary evaporation. The solvent was separated by column chromatography using a mixed solvent of hexane and ethyl acetate. 37 g (148 mmol, 81%) of (2-methyl) butyloxybenzene were obtained.

Preparation Example 3

Synthesis of Monomer M1

52.5 g (78 mmol) of the compound (IM-1) obtained in Example 1 and 23.3 g (93 mmol) of the compound (IM-2) obtained in Example 2 were dissolved in 1000 mL of dichloromethane at room temperature in a 2 L round flask. The solution was lowered to 0 ° C. and slowly injected with a solution of 7.5 g (78 mmol) of methane sulfonic acid in 100 mL of dichloromethane while stirring, followed by stirring for 2 hours. The reaction is poured into water, extracted with diethyl ether and the solvent is blown on a rotary evaporator. Separation by column chromatography, 2,7-dibromo-9- (9,9-dihexylfluoren-2-yl) -9- (3,4-di (2-methyl) butyloxyphenyl) flu 58.8 g (65 mmol, 83%) were obtained of orene (M1).

Preparation Example 4

Synthesis of -9- (9,9-dihexylfluoren-2-yl) -9- (3,4-di (2-methyl) butyloxyphenyl) fluorene-2,7-diboronic acid (IM-3)

58.8 g (65 mmol) of M1 was added to a 250 mL round flask, dissolved in THF 60 mL at room temperature, cooled to -70 ° C, and then slowly added 2 equivalents of 2.5 Mn-butyllithium at a low temperature of -70 to -40 ° C for 2 hours. After the reaction, 4 equivalents of triethyl borate are added at the same temperature and stirred for 12 hours. The reaction was poured into 3N-HCl aqueous solution, stirred for 4 hours, extracted with diethyl ether, the solvent was removed with a rotary evaporator, the solidified material was repeatedly washed with toluene, dried and 9,9-di (9). , 9-dihexyl) fluoren-2-yl-9- (3,4-di (2-methyl) butyloxyphenyl) fluorene-2,7-diboric acid (IM-3) 41.2 g (76%) Got.

Preparation Example 5

Synthesis of Monomer M2

Into a 100 mL round flask, 54.3 g (65 mmol) of the compound (IM-3) obtained in Example 4, 3 equivalents of ethylene glycol, and 50 mL of anhydrous toluene were added thereto, followed by installing a deanstark device for 24 hours. Reflux to remove water, and then recrystallized from hexane to give 9- (9,9-dihexyl) fluoren-2-yl-9- (3,4-di (2-methyl) butyloxyphenyl) florin-2, 50.2 g (57 mmol) 87% of 7-bis boronic glycol ester (M2) was obtained.

Preparation Example 6

Synthesis of Monomer M3

43.7 g (65 mmol) of the compound (IM-1) and 200 g of 9,9-dihexylfluorene were dissolved in 1000 mL of dichloromethane at room temperature in a 2 L round flask, and the temperature was lowered to 0 ° C., and 10 mL of methanesulfonic acid was stirred. The solution dissolved in 100 mL of dichloromethane is slowly injected and stirred for 2 hours. The reaction is poured into water and extracted with diethyl ether, then the solvent is blown on a rotary evaporator. Separation by column chromatography gave 37.3 g (38 mmol, 58%) of 9,9-di (9,9-dihexylfluoren-2-yl) -2,7-dibromofluorene (M3). .

Preparation Example 7

Synthesis of Monomer MF1

Mg 3.2g (133mmol) was added to a 500mL three-neck flask, and then 25.7g (133mmol) of 1-bromo-2,4-difluorobenzene was dissolved in THF 200mL at room temperature, and then slowly added dropwise while maintaining the reactor temperature at 65 ^° C. Make Grignard reagent. The temperature of the reactor was lowered to -5 ° C or lower, and then 30g (89mmol) of 2,7-dibromofluorenone was added under a nitrogen stream, and the temperature was gradually raised to room temperature, followed by stirring for 3 hours. The reaction is poured into water, extracted with diethyl ether and the solvent is blown on a rotary evaporator. Separation by column chromatography gave 31 g (68.6 mmol, 77%) of IM-4.

In a 2 L round flask, 5.6 g (12.43 mmol) of the compound (IM-4) and 14.5 g (43.4 mmol) of 9,9-dihexylfluorene were dissolved in 500 mL of dichloromethane, and the temperature was lowered to 0 ° C., while stirring. A solution of 1.5 mL of methanesulfonic acid dissolved in 100 mL of dichloromethane is slowly injected, followed by stirring for 2 hours. The reaction is poured into water and extracted with dichloromethane, then the solvent is blown on a rotary evaporator. Separation by column chromatography gave 5.6 g (7.3 mmol, 58%) of MF1 (see FIG. 5).

Preparation Example 8

Synthesis of Monomer MF2

In Example 7 except that 11g (36.7mmol) of 1-bromo-3,5-bis (trifluoromethyl) benzene as a substituent instead of 1-bromo-2,4-difluorobenzene was prepared in the same manner as in the synthesis of MF1 , 7.8 g (9 mmol, 66%) of MF2 was obtained.

Preparation Example 9

Synthesis of Monomer MF3

Except for using 7.2g (36.7mmol) 4-Bromo-1,2-difluorobenzene as a substituent instead of 1-bromo-2,4-difluorobenzene in Preparation Example 7, 9.8g prepared by the same method as the synthesis method of MF1 MF3 was obtained (16.6 mmol, 70%).

Preparation Example 10

Synthesis of Monomer MF4

In Preparation Example 7, except that 7.7 g (36.7 mmol) of 4-bromo-2-fluoro-1-methoxybenzene was used as a substituent instead of 1-bromo-2,4-difluorobenzene, and was prepared in the same manner as in the synthesis of MF1. 5.5 g (7.1 mmol, 56%) of MF4 was obtained.

Preparation Example 11

Synthesis of Monomer MF5

In the same manner as in the synthesis of MF1 except for using 9.4g (36.7mmol) of 4-bromo-2-fluoro-1,1'-biphenyl as a substituent instead of 1-bromo-2,4-difluorobenzene in Preparation Example 7 To give 6.1 g (7.4 mmol, 51%) of MF5.

Preparation Example 12

Synthesis of Monomer MF6

After dissolving 16.4g (73.0mmol) of 3-bromobenzotrifluoride in THF 300ml at room temperature, the temperature of the reactor was lowered to -70 ° C or lower, and then slowly injected with normal butyllithium 1.6M hexane solution under nitrogen stream, followed by stirring for 1 hour. .

10 g (27 mmol) of IM-5 was dissolved in 200 mL of THF, and then slowly injected into the reactor having a temperature of -70 ° C. or lower, followed by stirring for 3 hours. Water was added to the reaction, extracted with diethyl ether, and the solvent was blown on a rotary evaporator. Separation by column chromatography gave 9.5 g (15.1 mmol, 55.8%) of IM-6.

After dissolving 9.5 g (15.1 mmol) of the compound (IM-6) in 200 ml of acetic acid in a 2 L round flask, 2 ml of sulfuric acid was added and refluxed for 12 hours. Lower the temperature to room temperature, pour water and extract with dichloromethane, and then the solvent is blown by rotary evaporator. Separation by column chromatography gave 5.6 g (8.9 mmol) of MF6.

Preparation Example 13

Synthesis of Monomer MF7

Except for using 14.1g (73mmol) of 1-Bromo-3,5-difluorobenzene as a substituent in place of 3-bromobenzotrifluoride in Preparation Example 12, 5.6g (9.9mmol) of MF7 was prepared in the same manner as in the synthesis of MF6 Obtained.

Examples 1-8

-Synthesis of Electromolecules

Suzuki coupling reaction known as carbon-carbon coupling reaction using monomers M1, M2, M3, M4 and MF1, MF2, MF3, MF4, MF5, MF6, MF7 prepared by the method of Preparation Example (see Chemical Reviewa, Vol. 95, 1995, p. 2457-2483) to prepare a copolymer, its composition, and molecular weight are shown in Table 1 below. These polymers, with their new structural properties, had weight average molecular weights ranging from 496,000 to 872,000, respectively, with a high degree of polymerization of 2.5 to 3.5 PDI. This is in the range of molecular weight and PDI that can be easily provided by the solution process method.

division Polymer M1 (mol%) M2 (mol%) M4 (mol%) (mol%) Molecular Weight (Mw) Molecular Weight (Mn) PDI Example 1 P1-1 19.6 50 13 MF1 17.4 838,000 253,000 3.31 Example 2 P1-2 0 50 13 MF1 37 740,000 237,000 3.12 Example 3 P2 19.6 50 13 MF2 17.4 762,000 252,000 3.02 Example 4 P3 10.9 50 13 MF3 26.1 560,000 196,000 2.85 Example 5 P4-1 19.6 50 13 MF4 17.4 574,000 204,000 2.82 Example 6 P4-2 0 50 13 MF4 37 528,000 175,000 3.02 Example 7 P6 19.6 50 13 MF1 MF6 8.72 8.72 872,000 268,000 3.25 Example 8 P7 19.6 50 13 MF7 17.4 496,000 181,000 2.74 Comparative Example 1 S1 19.6 50 13 M3 17.4 446,000 156,000 2.85

Examples 9-16

-Manufacturing of electroluminescent device

After forming an indium-tin oxide (ITO) electrode on a glass substrate, spin coating PEDOT on top of the ITO electrode to form a thin film and drying the electroluminescence prepared from Examples 1 and 2 By spin coating the polymer for the device to form a light emitting layer of 700 ~ 1000Å thickness. Ba was deposited on the light emitting layer to a thickness of 50 kV and vacuum deposited aluminum of 1500 kW was used to fabricate an electroluminescent device, and the light emission characteristics thereof were measured.

division Light emitting layer Color coordinates (x, y) Highest efficiency [cd / A] Highest brightness [Cd / m ² ] Example 9 P1-1 (0.146, 0.143) 3.85 19,500 Example 10 P1-2 (0.148, 0.140) 3.58 16,200 Example 11 P2 (0.150, 0.157) 3.82 17,500 Example 12 P3 (0.150, 0.164) 3.70 13,700 Example 13 P4-1 (0.156, 0.178) 4.17 18,000 Example 14 P4-2 (0.168, 0.199) 4.33 21,000 Example 15 P6 (0.151, 0.158) 4.03 20,500 Example 16 P7 (0.156, 0.197) 4.45 22,000 Comparative Example 2 S1 (0.145, 0.132) 3.52 14,400

Electroluminescent polymers prepared from the above examples were introduced in the basic structure consisting of M1, M2, M3, MF1 ~ MF7 introduced a special functional group developed in the present invention and the hole injection and delivery function by introducing M4 to the hole injection and delivery properties It is the electric foot advertising molecules that improved. Electroluminescent devices manufactured using them have very good efficiency, color purity and maximum luminance.

 As indicated in the above examples, the polymer having a substituent containing fluorine shows higher efficiency and higher luminance than the polymer of Comparative Example 1 which is not. This is because the substituent containing F affects the recombination efficiency of electrons and holes.

In addition, the fluorine-containing substituents smooth the flow of electrons or holes, resulting in higher current density at the same voltage in the light emitting devices having the same manufacturing method and structure, resulting in higher maximum luminance. For example, Example 11 P1-1 shows a current density of 26.2 mA / cm ² at 5 V, and in Comparative Example 2 S1 without F, it has a current density of 15.1 mA / Cm ² at 5 V. FIG. For this reason, P1-1 has a maximum luminance of 19500 cd / m ² , while S1 has a maximum luminance of 14400 cd / m ² .

In addition, the hydrophobicity of fluorine prevents the penetration of moisture remaining in the PSS / PEDOT used in the manufacture of the polymer light emitting device or as the raw material of the hole injection layer, thereby improving the life of the polymer light emitting device. give.

From these results, it can be seen that the polymers developed in the present invention have excellent electroluminescence properties such as luminance, color purity, and efficiency, which are commercial aspects.

As described above, the electro-adhesion molecules incorporating the structural unit having a special substituent developed in the present invention have significantly improved the injection and transfer properties of electrons and holes, color purity and luminous efficiency, and excellent thermal stability and bulky substituents. It can minimize the intermolecular interactions, so it has high luminous efficiency and excellent solubility and makes thin thin film well. Therefore, when used as host material such as blue, green and red of organic electroluminescent device It is possible to express excellent light emission characteristics.

Claims (8)

Organic electro-adhesive molecule, characterized in that represented by the formula (1) or (2): <Formula 1>

<Formula 2>

Where R ₁ and R ₂ are the same as or different from each other, or an aryl group which is unsubstituted or substituted with at least one substituent selected from the group consisting of a C 1-20 straight or branched chain alkyl group and an alkoxy group containing F; R ₃ is a linear or branched alkyl group or alkoxy group having 1 to 20 carbon atoms; Ar ₁ is an arylamine group which is unsubstituted or substituted with at least one substituent selected from the group consisting of a linear or branched alkyl group having 1 to 20 carbon atoms and an alkoxy group; Ar ₂ is selected from the group consisting of C6-C60 substituted or unsubstituted aromatic compounds, C2-C60 substituted or unsubstituted heteroaromatic compounds, and combinations thereof; And, x is an integer of 1-10,000, y is an integer of 0-10,000, z is an integer of 1-100,000. The chemical formula of claim 1, wherein x in Chemical Formula 1 is an integer of 1 to 10,000, y is an integer of 0 to 10,000, z is an integer of 4 to 100,000, x / y is 1:19 or more, and x :( y + z) is an organic electroluminescent advertising molecule, characterized in that having a ratio of 5: 95 to 90: 10. The organic electro-adhesive molecule of claim 1, wherein R ₃ is selected from the following compounds.

The method of claim 1, wherein Ar ₂ , (Iii) a C6 to C60 substituted or unsubstituted arylene group; (Ii) a C2 to C60 substituted or unsubstituted heterocyclic arylene group wherein at least one hetero atom selected from the group consisting of N, S, O, P and Si is included in the aromatic ring; (Iii) a C 6 to C 60 substituted or unsubstituted arylenevinylene group; And (iv) selected from the group consisting of combinations thereof Herein, the substituents of Ar ₁ and Ar ₂ may be the same or different, and may be a linear or branched alkyl or alkoxy group having 1 to 20 carbon atoms; An aryl group which is unsubstituted or substituted with at least one substituent selected from the group consisting of a linear or branched alkyl group having 1 to 20 carbon atoms and an alkoxy group; Cyano group (-CN); And silyl groups. Organic electro-adhesive molecules, characterized in that selected from the group consisting of. The organic electroluminescent polymer according to claim 1, wherein Ar ₁ is selected from the following compounds.

According to claim 1, wherein the organic electro-adhesive molecules have an average molecular weight of 800 ~ 4,000,000, the molecular weight distribution of the organic electro-adhesive molecules, characterized in that 1 ~ 10. An organic electricity comprising at least one layer between an anode and a cathode comprising an organic electro-adhesive molecule according to any one of claims 1 to 6, wherein said layer is a major transport layer, a light emitting layer or an electron transport layer. Light emitting element. The organic electroluminescent device according to claim 7, wherein the structure of the electroluminescent device is an anode / light emitting layer / cathode, an anode / hole transporting layer / light emitting layer / cathode, or an anode / hole transporting layer / light emitting layer / electron transporting layer / cathode.

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