HK1228580B - Organic electroluminescent device - Google Patents

Abstract

The present invention relates to an organic electroluminescent device,Including anode,Cathode,And the organic layer,The organic layer is a hole injection layerHole transport layerElectron injection layerElectronic transport layerAt least one or more layers including the luminescent layer in the luminescent layer;The luminescent layer is a host guest doping system composed of a host material and a guest material,The luminescent region of the luminescent layer is blue 440-490nm,The host material or guest material has a compound with the structure described in formula (I),This organic electroluminescent device has the advantages of good electroluminescent efficiency, excellent color purity, and long lifespan.

Description

Organic electroluminescent device

Technical Field

The invention relates to an organic electroluminescent blue light device prepared from a novel organic host material, belonging to the technical field of organic electroluminescent device display.

Background

The organic electroluminescent device as a novel display technology has the unique advantages of self luminescence, wide viewing angle, low energy consumption, high efficiency, thinness, rich colors, high response speed, wide applicable temperature range, low driving voltage, capability of manufacturing flexible, bendable and transparent display panels, environmental friendliness and the like, so the organic electroluminescent device technology can be applied to flat panel displays and new generation illumination and can also be used as a backlight source of LCDs.

An organic electroluminescent device is a device prepared by spin-coating or depositing a layer of organic material between two metal electrodes, and a typical three-layer organic electroluminescent device includes a hole transport layer, a light emitting layer, and an electron transport layer. Holes generated by the anode are combined with electrons generated by the cathode through the hole transport layer and the electron transport layer to form excitons in the light emitting layer, and then the excitons emit light. The organic electroluminescent device can emit red, green and blue light by changing the material of the light emitting layer. Therefore, the stable, efficient and color-pure organic electroluminescent material has an important role in the application and popularization of organic electroluminescent devices, and is also an urgent need for the application and popularization of large-area panel display of OLEDs.

Among the three primary colors (red, blue, green), the red and green materials have been greatly developed recently, and although the efficiency of the red and green organic electroluminescent devices has been significantly improved and also meets the market demand of the panel, the efficiency and stability thereof still need to be further improved. It is therefore a focus of research in this field to address the above problems from material design and device structure. In dye-doped organic electroluminescent devices, the efficiency of energy transfer from host materials to doped emitters has a large impact on the performance and stability of the devices. Frequently used host materials include mCP and 26DCzPPy and their derivatives, both containing nitrogen atoms. The material containing only hydrocarbon has high relative stability, and is suitable for industrial application and commercialization. For the host material of the blue fluorescent dye doped device, there are a series of commercial materials, wherein 9, 10-Diphenylanthracene (DPA), 9, 10-di (naphthalene-2-yl) Anthracene (ADN) and 2-methyl-9, 10-di (naphthalene-2-yl) anthracene (MADN) are used in a large amount in the early stage, and the device prepared by using the compounds has a relatively general efficiency, and also because of the easy crystallization characteristic generated by the symmetry of molecules, the thin film form of the device is easy to change, the stability of the device is reduced, and thus the blue fluorescent dye doped device cannot be used in the OLED industry in a large amount.

Disclosure of Invention

The invention overcomes the defects of the device and provides the organic electroluminescent fluorescent dye doped blue light emitting device with good electroluminescent efficiency, excellent color purity and long service life.

An organic electroluminescent device comprises an anode, a cathode and an organic layer, wherein the organic layer is one or more of a hole injection layer, a hole transport layer, an electron injection layer, an electron transport layer and a light-emitting layer, and the light-emitting layer at least comprises a light-emitting layer; the luminescent layer is a host-guest doping system consisting of a host material and a guest material, the luminescent region of the luminescent layer is blue 440-490nm, the host material or the guest material is a compound with the structure shown in the formula (I),

wherein R is₁-R₁₇Independently represent hydrogen, deuterium atom, halogen, cyano, nitro, C1-C8 alkyl, C1-C8 alkoxy, substituted or unsubstituted aryl of C6-C30, substituted or unsubstituted aryl of C3-C30 containing one or more heteroatoms, C2-C8 substituted or unsubstituted alkylene, C2-C8 substituted or unsubstituted alkynylalkyl, wherein Ar is Ar₁-Ar₃Independently represent a C6-C60 substituted or unsubstituted aryl group, a C3-C60 substituted or unsubstituted heteroaryl group with one or more heteroatoms, and a tri-aromatic (C6-C30) amine group.

Preferably: wherein R is₁-R₁₇Independently represent hydrogen, halogen, cyano, nitro, C1-C8 alkyl, C1-C8 alkoxy, C2-C8 substituted or unsubstituted alkenylalkyl, C2-C8 substituted or unsubstituted alkynylalkyl, C1-C4 alkyl substituted or unsubstituted phenyl, C1-C4 alkyl substituted or unsubstituted naphthyl, or fluorenyl combined to form C1-C4 alkyl substituted or unsubstituted fluorenyl; ar (Ar)₁-Ar₃Independently represent C1-C4 alkyl or C6-C30 aryl substituted phenyl, C1-C4 alkyl or C6-C30 aryl substituted naphthyl, phenyl, naphthyl, pyridyl, N-C6-C30 aryl or C1-C4 alkyl substituted carbazolyl, dibenzothienyl, dibenzofuranyl, anthryl, phenanthryl, pyrenyl, perylenyl, anthryl, (9, 9-dialkyl) fluorenyl, (9, 9-dialkyl substituted or unsubstituted aryl) Fluorenyl, 9, 9-spirofluorenyl.

Preferably: wherein R is₁-R₂May independently preferably represent hydrogen, halogen, C1-C4 alkyl, C1-C4 alkyl substituted or unsubstituted phenyl, C1-C4 alkyl substituted or unsubstituted naphthyl, or fluorenyl substituted or unsubstituted with C1-C4 alkyl combined; wherein R is₃-R₁₇May independently preferably represent hydrogen, halogen, C1-C4 alkyl, C1-C4 alkyl substituted or unsubstituted phenyl, C1-C4 alkyl substituted or unsubstituted naphthyl, preferably Ar₁-Ar₃Independently represent phenyl, tolyl, xylyl, tert-butylphenyl, naphthyl, pyridyl, methylnaphthalene, biphenyl, diphenylphenyl, naphthylphenyl, diphenylbiphenyl, diarylaminophenyl, N-phenylcarbazolyl, (9, 9-dialkyl) fluorenyl, (9, 9-dialkyl substituted or unsubstituted phenyl) fluorenyl, 9, 9-spirofluorenyl.

Preferably: wherein R is₃-R₁₇Preferably hydrogen, R₁，R₂May independently preferably be represented by hydrogen, methyl, ethyl, propyl, isopropyl, tert-butyl, phenyl, biphenyl, naphthyl, or combined to form a fluorenyl group; ar (Ar)₁-Ar₃Independently represent phenyl, pyridyl, tolyl, xylyl, naphthyl, methylnaphthyl, biphenyl, diphenylphenyl, naphthylphenyl, diphenylbiphenyl, (9, 9-dialkyl) fluorenyl, (9, 9-dimethyl substituted or unsubstituted phenyl) fluorenyl, 9, 9-spirofluorenyl.

Preferably: r₃-R₁₇Preferably hydrogen; r₁，R₂Independently represent hydrogen, methyl, or combine to form fluorenyl; ar (Ar)₁，Ar₂，Ar₃Independently represent phenyl, naphthyl.

Preferably: the compound of formula (I) is a compound of the following structure

The organic layer is one or more of a hole injection layer, a hole transport layer, a light emitting layer, a hole blocking layer and an electron transport layer. It is to be specifically noted that the above organic layers may be used as desired, and that these organic layers are not necessarily present in every layer.

The hole transport layer, the electron transport layer and/or the light-emitting layer contain the compound of formula (I).

The compound of formula (I) is located in the light-emitting layer.

The organic electroluminescent device at least comprises a luminescent layer, and the luminescent region of the luminescent layer is at 440 nm and 490nm of blue light.

The light-emitting layer is a host-guest doping system composed of a host material and a guest material.

The compound of the formula (I) is a host material and/or a guest material.

In the doped system, the concentration of the host material is 20 to 99.9%, preferably 80 to 99%, and more preferably 90 to 99% by weight of the entire light-emitting layer. And accordingly the concentration of the guest material is 0.01 to 80%, preferably 1 to 20%, more preferably 1 to 10% by weight of the entire light-emitting layer.

The total thickness of the organic layers of the electronic device of the present invention is 1 to 1000nm, preferably 1 to 500nm, more preferably 50 to 300 nm.

The organic layer may be formed into a thin film by evaporation or spin coating.

As mentioned above, the compounds of formula (I) according to the invention are as follows, but are not limited to the structures listed:

the hole transport layer and the hole injection layer in the invention have good hole transport performance of the required materials, and can effectively transport holes from the anode to the organic light-emitting layer. May include small molecules and high molecular organic materials, and may include, but is not limited to, triarylamine compounds, biphenyldiamine compounds, thiazole compounds, oxazole compounds, imidazole compounds, fluorene compounds, phthalocyanine compounds, hexacyano hexaazatriphenylene (hexanitrile hexaazatriphenylene), 2,3,5, 6-tetrafluoro-7, 7',8,8' -tetracyanodimethyl-p-benzoquinone (F4-TCNQ), polyvinylcarbazole, polythiophene, polyethylene, and polyphenylsulfonic acid.

The organic electroluminescent layer of the present invention may contain, in addition to the compound of the formula (I) of the present invention, but is not limited thereto, naphthalene compounds, pyrene compounds, fluorene compounds, phenanthrene compounds, anthracene compounds, pentacene compounds, perylene compounds, diarylethene compounds, triphenylamine ethene compounds, amine compounds, benzimidazole compounds, furan compounds, and organic metal chelate compounds.

The organic electron transport material used in the organic electronic device of the present invention is required to have excellent electron transport performance, and to be capable of efficiently transporting electrons from the cathode to the light-emitting layer, and the following compounds may be selected, but not limited thereto, oxazaoles, thiazole compounds, triazole compounds, triazine compounds, quinoxaline compounds, diazananthracene compounds, silicon-containing heterocyclic compounds, quinoline compounds, phenanthroline compounds, metal chelates, and fluorine-substituted benzene compounds.

The organic electronic device of the present invention may be incorporated with an electron injection layer which can efficiently inject electrons from the cathode into the organic layer, and is selected from compounds mainly of alkali metals or compounds of alkaline earth metals or alkaline earth metals, and the following compounds may be selected, but not limited thereto, lithium fluoride, lithium oxide, lithium nitride, 8-hydroxyquinoline lithium, cesium carbonate, 8-hydroxyquinoline cesium, calcium fluoride, calcium oxide, magnesium fluoride, magnesium carbonate, magnesium oxide.

Device experiments show that the organic electroluminescent device has the advantages of good electroluminescent efficiency, excellent color purity and long service life.

Drawings

Figure 1 is a diagram of the structure of a device of the present invention,

wherein 10 is represented by a glass substrate, 20 is represented by an anode, 30 is represented by a hole injection layer, 40 is represented by a hole transport layer, 50 is represented by a light emitting layer, 60 is represented by an electron transport layer, 70 is represented by an electron injection layer, and 80 is represented by a cathode.

FIG. 2 is a drawing of Compound 89¹H NMR chart.

FIG. 3 is a drawing of Compound 89¹³C NMR chart.

Figure 4 is an HPLC profile of compound 89.

Figure 5 is a TGA profile of compound 89.

FIG. 6 is a graph of voltage-current density curves of examples 4 and 5 and comparative example 1

FIG. 7 is a graph of voltage-current density curves of examples 6 and 7 and comparative example 2

FIG. 8 is a graph showing the voltage-current density curves of examples 8 and 9 and comparative example 3

FIG. 9 is a graph of current density-current efficiency for examples 4 and 5 and comparative example 1

FIG. 10 is a graph of current density-current efficiency for examples 6 and 7 and comparative example 2

FIG. 11 is a graph of current density-current efficiency for examples 8 and 9 and comparative example 3

FIG. 12 shows electroluminescence spectra of examples 4 and 5 and comparative example 1

FIG. 13 shows electroluminescence spectra of examples 6 and 7 and comparative example 2

FIG. 14 shows electroluminescence spectra of examples 8 and 9 and comparative example 3

FIG. 15 is a graph of luminance versus CIEy for examples 4 and 5 and comparative example 1

FIG. 16 is a graph of luminance versus CIEy for examples 6 and 7 and comparative example 2

FIG. 17 is a graph of luminance versus CIEy for examples 8 and 9 and comparative example 3

Detailed Description

In order to describe the present invention in more detail, the following examples are given, but not limited thereto.

(wherein the following compounds 1a, 1b, 1e, 1h, 3a and 89a are commercially available materials in common use)

Example 1

Synthesis of intermediate 1c

To a reaction flask was added 1a (240.00g,0.88mol),1b (496.32g,1.76mol), Pd (PPh)₃)₄(20.35g,17.60mmol), potassium carbonate (302.52g,2.20mol), toluene (2400mL), pure water (1200 mL). And pumping nitrogen for three times, starting heating, keeping the temperature of the reaction liquid to be 95-105 ℃, reacting for 8-12h, sampling TLC and HPLC, and completely reacting the raw materials. Stopping heating, cooling to 20-30 deg.C, vacuum filtering, separating organic layer from filtrate, extracting water layer with ethyl acetate, mixing organic layers, washing with water, drying with anhydrous magnesium sulfate, vacuum filtering, and concentrating filtrate to obtain dark yellow solid crude product. Recrystallizing with petroleum ether to obtain the off-white solid product with the yield of 90 percent and the purity of 95 percent.

Synthesis of intermediate 1d

To the reaction flask was added 1c (302g,0.78mol), B (OEt) in the corresponding proportions₃(142g,0.97mol), n-BuLi/THF (1.6M,600mL) and anhydrous THF (3000mL), pumping nitrogen for three times, cooling to the temperature of the reaction solution to-75-65 ℃, slowly dropwise adding the n-BuLi/THF solution, controlling the temperature of the reaction solution to-75-65 ℃, and continuously keeping the temperature after dropwise adding for reaction for 0.5-1 h. Then adding a certain amount of B (OEt)₃Dropwise adding the mixture, controlling the temperature of the reaction solution to be-75 to-65 ℃, continuously keeping the temperature for reacting for 0.5 to 1 hour after the dropwise adding is finished, then moving the reaction solution to room temperature for naturally heating and reacting for 4 to 6 hours, then adding 2M dilute hydrochloric acid, adjusting the pH value to 2 to 3, stirring for about 1 hour, and stopping the reaction. Adding ethyl acetate for extraction, extracting a water layer with EA, combining organic layers, drying with anhydrous magnesium sulfate, performing suction filtration, and concentrating a filtrate to obtain an off-white solid product with the purity of 95% and the yield of 62.5%.

Synthesis of intermediate 1f

To a reaction flask was added 1d (150g,0.43mol),1e (500g,0.86mol), Pd (PPh)₃)₄(5.0g,0.44mmol), potassium carbonate (130g,0.92mol), toluene (1000mL), pure water(500mL), nitrogen is pumped out for three times, heating is started, the temperature of the reaction liquid reaches 95-105 ℃, the reaction liquid is kept at the temperature for 8-12h, and TLC and HPLC are sampled, so that the raw materials are completely reacted. Stopping heating, cooling to 20-30 deg.C, vacuum filtering, separating organic layer from filtrate, extracting water layer with ethyl acetate, mixing organic layers, drying with anhydrous magnesium sulfate, vacuum filtering, and concentrating filtrate to obtain dark yellow solid crude product with purity of 80% and yield of 78.1%.

Synthesis of intermediate 1g

1f (210g,0.42mol), NBS (135g,0.71mol), DMF (5L) was added to the reaction flask. And pumping nitrogen for three times, starting heating, keeping the temperature of the reaction liquid to be 60-65 ℃, reacting for 6-8h, sampling TLC and HPLC, and completely reacting the raw materials. Stopping heating, cooling to 20-30 ℃, pouring the reaction liquid into ice water, separating out dark yellow solid, performing suction filtration to obtain yellow solid, and drying to obtain 1g of crude product. Adding DCM/MeOH into the crude product until the solution becomes slightly turbid, stirring for about 30min to precipitate a large amount of solid, and vacuum filtering to obtain light yellow solid product with yield of about 54.05% and purity of 98.5%

¹H NMR(300MHz,CDCl₃)δ8.64(d,J＝8.8Hz,2H),7.99–7.90(m,4H),7.87(t,J＝1.6Hz,1H),7.78(dd,J＝9.3,2.3Hz,6H),7.61(ddd,J＝8.8,6.5,1.1Hz,2H),7.56–7.48(m,6H),7.46–7.38(m,4H).

¹³C NMR(76MHz,CDCl₃)δ142.67(s),142.03(s),141.26(s),140.69(s),137.83(s),137.52(s),131.87(s),131.24(s),130.44(s),129.09(s),128.80(s),128.38–127.40(m),127.18(s),126.05–125.21(m),123.08(s),77.74(s),77.31(s),76.89(s),30.10(s).

Synthesis of Compound 1

Into a 500ml three-necked flask were charged 1g (9.5g,16.92mmol),1h (6.41g,30.51mmol), Pd (PPh) in that order₃)₄(1.5g,1.3mmol), potassium carbonate (5.84g,42.3mmol), toluene (150mL), and pure water (75 mL). After nitrogen was purged three times, the reaction was carried out at 105 ℃. The reaction time is about 12h by liquid phase detection. The reaction mixture was made yellowish-earthy at the beginning of the reaction and slowly turned yellowThe solution is colored, the upper layer is clear light yellow after the reaction is stopped, and the lower layer is water. And after the reaction is stopped, filtering, washing filter residues by using ethyl acetate until no product exists in the filter residues, collecting filtrate, spin-drying, separating out a large amount of off-white solid, collecting the filter residues, and drying to obtain the target product with the purity of 98%. Sublimation in vacuo gave an off-white solid powder with a purity of 99.5%.

¹H-NMR(300MHz,CDCl₃)δ8.10–8.21(d，2H)，7.96–7.98(dd，3H)，7.87–7.89(m，2H)，7.81–7.86(m，4H)，7.78–7.81(d，4H),7.62–7.65(m，2H)，7.59(s，1H)，7.51–7.57(m，5H)，7.45–7.48(m，2H)，7.36–7.43(m，7H)，3.88(s，2H).

Example 2

Synthesis of Compound 3

Into a 500ml three-necked flask were charged 1g (9.5g,16.92mmol),3a (7.25g,30.46mmol), Pd (PPh) in that order₃)₄(1.5g,1.3mmol), potassium carbonate (5.84g,42.3mmol), toluene (150mL), and pure water (75 mL). After nitrogen was purged three times, the reaction was carried out at 105 ℃. The reaction time is about 12h by liquid phase detection. The reaction solution was made to be a yellowish-earthy catalyst at the beginning of the reaction, and then slowly changed to a yellow solution, and after the reaction was stopped, the upper layer was a clear pale yellow and the lower layer was water. And after the reaction is stopped, filtering, washing filter residues by using ethyl acetate until no product exists in the filter residues, collecting filtrate, spin-drying, separating out a large amount of off-white solid, collecting the filter residues, and drying to obtain the target product with the purity of 98%. Sublimation in vacuo gave an off-white solid powder with a purity of 99.7%.

¹H-NMR(300MHz,CDCl₃)δ8.1–8.2(d，2H)，7.96–7.99(dd，3H)，7.88–7.89(m，2H)，7.81–7.86(m，4H)，7.78–7.81(d，4H),7.61–7.65(m，2H)，7.59(s，1H)，7.51–7.56(m，5H)，7.46–7.48(m，2H)，7.35–7.43(m，7H)，1.61(s，6H).

Example 3

Synthesis of Compound 89

To the reaction vessel were added 1g (10.0g,17.8mmol),89a (7.1g,19.6mmol), Pd (PPh) in that order₃)₄(432.2mg,0.35mmol),K₂CO₃(6.14g,44.5mmol), toluene (300mL) and water (150mL), the apparatus was deoxygenated, purged with nitrogen, and then heated to 100 deg.C for reaction overnight. With DCM: the PE is a ratio of 1:5, the product point emits strong blue light under an ultraviolet lamp with the wavelength of 365nm, and the Rf value is about 0.2. The reaction solution was filtered by suction through silica gel, and the filter cake was washed twice with ethyl acetate (100mL), separated, the aqueous layer was extracted once with ethyl acetate (100mL), the organic layers were combined, and the organic phase was washed once with water (200 mL). The solvent was removed by spin-drying. The crude product was recrystallized from 120ml DCM/MeOH and filtered off with suction to give 13.1g of a yellow solid powder with a purity of 98.7% in 92.2% yield. Sublimation in vacuo gave a pale yellow solid powder with a purity of 99.7%. And m/z is 797.

From fig. 2 and 3, it can be seen that the hydrogen spectrum and the carbon spectrum of compound 89 are completely consistent with the structure. It can be seen from the high performance liquid chromatogram of compound 89 of fig. 4 that the product prepared according to the synthesis method of the present invention has high purity. From the thermogravimetric analysis of compound 89 of fig. 5, it can be seen that this type of compound has a decomposition temperature above 400 degrees celsius, indicating a very high thermal stability.

Example 4

Preparation of organic electroluminescent device 1

Preparation of OLEDs Using the organic electronic Material of the invention

First, a transparent conductive ITO glass substrate 10 (with an anode 20 thereon) is sequentially passed through: washing with detergent solution, deionized water, ethanol, acetone and deionized water, and treating with oxygen plasma for 30 s.

Then, HAT-CN was evaporated on the ITO to a thickness of 10nm₆As the hole injection layer 30.

Then, NPB was evaporated to form a hole transport layer 40 having a thickness of 30 nm.

Then, the compound B1 (2%) and the compound 3 (98%) were evaporated to a thickness of 30nm on the hole transport layer to form the light-emitting layer 50.

Then, TPBi having a thickness of 15nm was deposited on the light-emitting layer as an electron transporting layer 60.

Finally, a 15nm BPhen is evaporated, Li is an electron injection layer 70, and 150nm Al is used as a device cathode 80.

The prepared device is at 20mA/cm²The voltage under the working current density of the LED is 3.87V, the current efficiency reaches 4.57cd/A, the peak value of the emitted blue light is 460nm, and the voltage is 1000cd/m²CIEy at brightness was 0.135.

Structural formula in device

Example 5

Preparation of organic electroluminescent device 2

In the same manner as in example 4, compound 3 was replaced with compound 89 to fabricate an organic electroluminescent device.

The prepared device is at 20mA/cm²Has a voltage of 4.9 at the operating current density1V, the current efficiency reaches 4.31cd/A, the peak value of the emitted blue light is 456nm, and the peak value is 1000cd/m²CIEy at brightness was 0.143.

Example 6

Preparation of organic electroluminescent device 3

In the same manner as in example 4, an organic electroluminescent element was produced by replacing compound B1 with compound B2.

The prepared device is at 20mA/cm²The voltage under the working current density of the LED is 4.09V, the current efficiency reaches 5.27cd/A, the peak value of the emitted blue light is 460nm, and the voltage is 1000cd/m²CIEy at brightness was 0.155.

Example 7

Preparation of organic electroluminescent device 4

In the same manner as in example 6, compound 3 was replaced with compound 89 to fabricate an organic electroluminescent device.

The prepared device is at 20mA/cm²The voltage under the working current density of the LED is 4.94V, the current efficiency reaches 5.05cd/A, the peak value of the emitted blue light is 460nm, and the voltage is 1000cd/m²CIEy at brightness was 0.160.

Example 8

Preparation of organic electroluminescent device 5

In the same manner as in example 4, an organic electroluminescent element was produced by replacing compound B1 with compound B3.

The prepared device is at 20mA/cm²The voltage under the working current density of the LED is 4.54V, the current efficiency reaches 3.07cd/A, the peak value of the emitted blue light is 452nm, and the voltage is 1000cd/m²CIEy at brightness was 0.105.

Example 9

Preparation of organic electroluminescent device 6

In the same manner as in example 8, compound 3 was replaced with compound 89 to fabricate an organic electroluminescent device.

The prepared device is at 20mA/cm²The voltage under the working current density of the LED is 5.54V, the current efficiency reaches 1.44cd/A, the peak value of the emitted blue light is 452nm, and the voltage is 1000cd/m²CIEy at luminance was 0.101.

Comparative example 1

Preparation of organic electroluminescent device 7

In the same manner as in example 4, compound 3 was replaced with compound MADN to fabricate an organic electroluminescent device.

The prepared device is at 20mA/cm²The voltage under the working current density of the LED is 5.24V, the current efficiency reaches 2.60cd/A, the peak value of the emitted blue light is 460nm, and the voltage is 1000cd/m²CIEy at brightness was 0.164.

Comparative example 2

Preparation of organic electroluminescent device 8

In the same manner as in example 6, Compound 3 was replaced with Compound MADN to fabricate an organic electroluminescent device.

The prepared device is at 20mA/cm²The voltage under the working current density of the LED is 5.18V, the current efficiency reaches 4.79cd/A, the peak value of the emitted blue light is 460nm, and the voltage is 1000cd/m²CIEy at brightness was 0.161.

Comparative example 3

Preparation of organic electroluminescent device 9

In the same manner as in example 8, Compound 3 was replaced with Compound MADN to fabricate an organic electroluminescent device.

The prepared device is at 20mA/cm²To a workerThe voltage under the action of current density is 4.89V, the current efficiency reaches 2.10cd/A, the peak value of emitted blue light is 456nm, and the voltage is 1000cd/m²CIEy at luminance was 0.132.

Examples 4,5,6,7,8 and 9 are specific applications of the material of the present invention, and the prepared device emits blue light, has better luminous efficiency and brightness and lower CIEy value than the comparative example, and proves to be suitable for the organic electroluminescent fluorescent dye-doped blue light emitting device. As described above, the material of the present invention has high stability, and the organic electroluminescent device prepared by the present invention has high efficiency and optical purity.

Claims (11)

1. An organic electroluminescent device comprises an anode, a cathode and an organic layer, wherein the organic layer is one or more of a hole injection layer, a hole transport layer, an electron injection layer, an electron transport layer and a light-emitting layer, and the light-emitting layer at least comprises a light-emitting layer; the luminescent layer is a host-guest doping system consisting of a host material and a guest material, the luminescent region of the luminescent layer is blue 440-490nm, the host material or the guest material is a compound with the structure shown in the formula (I),

wherein R is₁-R₁₇Independently represent hydrogen, C1-C8 alkyl, C1-C8 alkoxy, C1-C4 alkyl substituted or unsubstituted phenyl, C1-C4 alkyl substituted or unsubstituted naphthyl, or combine to form C1-C4 alkyl substituted or unsubstituted fluorenyl; ar (Ar)₁-Ar₃Independently represent C1-C4 alkyl or C6-C30 aryl substituted phenyl, C1-C4 alkyl or C6-C30 aryl substituted naphthyl, phenyl, naphthyl, pyridyl.

2. The organic electroluminescent device according to claim 1, wherein R₁-R₂May independently represent hydrogen, C1-C4 alkyl, C1-C4 alkyl substituted or unsubstituted phenyl, C1-C4 alkyl substituted or unsubstituted naphthyl, or fluorenyl substituted or unsubstituted alkyl combined to form C1-C4; wherein R is₃-R₁₇Can be independently represented by hydrogen, C1-C4 alkyl, C1-C4 alkyl substituted or unsubstituted phenyl, C1-C4 alkyl substituted or unsubstituted naphthyl, Ar₁-Ar₃Independently represent phenyl, tolyl, tert-butylphenyl, naphthyl, pyridyl, methylnaphthalene, biphenyl, diphenylphenyl, naphthylphenyl.

3. The organic electroluminescent device according to claim 2, wherein R₃-R₁₇Is hydrogen, R₁，R₂Independently represent hydrogen, methyl, ethyl, propyl, isopropyl, tert-butyl, phenyl, naphthyl; ar (Ar)₁-Ar₃Independently represent phenyl, pyridyl, tolyl, naphthyl, methylnaphthalene, biphenyl.

4. The organic electroluminescent device according to claim 3, R₃-R₁₇Is hydrogen; r₁，R₂Independently represent hydrogen, methyl, or combine to form fluorenyl; ar (Ar)₁，Ar₂，Ar₃Independently represent phenyl, naphthyl.

5. An organic electroluminescent device according to claim 1, wherein the compound of formula (I) is:

6. the organic electroluminescent device according to claim 5, wherein the compound of formula (I) is a compound of the following structure:

7. the organic electroluminescent device according to any one of claims 1 to 6, wherein the concentration of the host material is 20 to 99.9% by weight of the entire light-emitting layer, and the concentration of the guest material is 0.01 to 80% by weight of the entire light-emitting layer.

8. The organic electroluminescent device according to claim 7, wherein the concentration of the host material is 80 to 99% by weight of the entire light emitting layer, and the concentration of the guest material is 1 to 20% by weight of the entire light emitting layer.

9. The organic electroluminescent device according to claim 8, wherein the host material is a compound having a structure represented by formula (I) and has a concentration of 90-99% by weight of the entire light-emitting layer; the concentration of the guest material is 1 to 10% by weight of the entire light-emitting layer.

10. The organic electroluminescent device of claim 9, the guest material being one or more of the following structures,

11. the organic electroluminescent device according to claim 8, wherein the compound of formula (I) is further located in a hole injection layer, a hole transport layer, an electron transport layer and/or an electron injection layer.