ORGANIC ELECTROLUMINESCENT DEVICE

Abstract

This invention relates to an OLED, comprising an anode, a cathode, and an organic layer, the organic layer at least contains one or more layers containing light emitting layer from the hole injection layer, hole transport layer, electron injection layer, electron transport layer, light emitting layer; the light emitting layer is a host guest doping system composed of host materials and guest materials. The light-emitting zone of the light emitting layer is 490-750 nm, and the host material has a structure with the formula (I). The OLED can emit red or green light, with the advantages of excellent light emitting efficiency, excellent color purity and long lifetime.

##STR00001##

Claims

1. An OLED, comprising an anode, a cathode, and an organic layer, the organic layer at least contains one or more layer containing light emitting layer from the hole injection layer, hole transport layer, electron injection layer, electron transport layer, light emitting layer; the light emitting layer is a host guest doping system composed of host materials and guest materials, the light-emitting zone of the light emitting layer is 490-750 nm, and the host material has a structure with the formula (I), ##STR00037## Wherein R.sub.1-R.sub.17 independently represent hydrogen, deuterium, halogen, cyano, nitro, C1-C8 alkyl, C1-C8 alkoxy, C6-C30 substituted or unsubstituted aryls, C3-C30 substituted or unsubstituted aryls containing one or more heteroatoms, C2-C8 substituted or unsubstituted alkenyl, C2-C8 substituted or unsubstituted alkynyl, wherein Ar.sub.1-Ar.sub.3 independently represent C6-C60 substituted or unsubstituted aryl, C3-C60 substituted or unsubstituted heteroaryl containing one or more heteroatoms, triaryl (C6-C30) amine.

2. The OLED according to claim 1, wherein R.sub.1-R.sub.17 independently represent hydrogen, halogen, cyano, nitro, C1-C8 alkyl, C1-C8 alkoxy, C2-C8 substituted or unsubstituted alkenyl, C2-C8 substituted or an unsubstituted alkynyl, C1-C4 alkyl substituted or unsubstituted phenyl, C1-C4 alkyl substituted or unsubstituted naphthyl, or combined C1-C4 alkyl substituted or unsubstituted fluorenyl; Ar.sub.1-Ar.sub.3 independently 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, fluoranthenyl, (9,9)-dialkyl) fluorenyl, (9,9-dialkyl substituted or unsubstituted aryl) fluorenyl, 9,9-spirofluorenyl.

3. The OLED according to claim 2, wherein R.sub.1-R.sub.2 independently and preferably represent hydrogen, halogen, C1-C4 alkyl, C1-C4 alkyl substituted or unsubstituted phenyl, C1-C4 alkyl substituted or unsubstituted naphthyl, or combined C1-C4 alkyl-substituted or unsubstituted fluorenyl; wherein R.sub.3-R.sub.17 may independently represent hydrogen, halogen, C1-C4 alkyl, C1-C4 alkyl substituted or unsubstituted phenyl, C1-C4 alkyl-substituted or unsubstituted naphthyl, preferably Ar.sub.1-Ar.sub.3 independently represent phenyl, tolyl, xylyl, t-butylphenyl, naphthyl, pyridyl, methyl naphthalene, biphenyl, diphenylphenyl, naphthylphenyl, diphenylbiphenyl, diarylamine phenyl, N-phenylcarbazolyl, (9,9-dialkyl) fluorenyl, (9,9-dialkyl substituted or unsubstituted phenyl) fluorenyl, 9,9-spirofluorenyl.

4. The OLED according to claim 3, wherein R.sub.3-R.sub.17 preferably represents hydrogen, and R1 and R2 may independently represent hydrogen, methyl, ethyl, propyl, isopropyl, t-butyl, phenyl, biphenyl, naphthyl, or combined fluorenyl; Ar.sub.1-Ar.sub.3 may independently represent phenyl, pyridyl, tolyl, xylyl, naphthyl, methylnaphthalene, biphenyl, diphenylphenyl, naphthylphenyl, diphenylbiphenyl, (9,9-dialkyl) fluorenyl, (9,9-dimethyl-substituted or unsubstituted phenyl) fluorenyl, 9,9-spirofluorenyl.

5. The OLED according to claim 4, wherein R.sub.3-R.sub.17 represent hydrogen preferably; R.sub.1, R.sub.2 independently represent hydrogen, methyl or combined fluorenyl; Ar.sub.1, Ar.sub.2, Ar.sub.3 independently represent phenyl and naphthyl.

6. The OLED according to claim 1, wherein a compound with the structure (I) is: ##STR00038## ##STR00039## ##STR00040## ##STR00041## ##STR00042## ##STR00043## ##STR00044## ##STR00045## ##STR00046## ##STR00047## ##STR00048## ##STR00049## ##STR00050## ##STR00051## ##STR00052## ##STR00053## ##STR00054## ##STR00055## ##STR00056## ##STR00057## ##STR00058## ##STR00059## ##STR00060##

7. The OLED according to claim 6, wherein it is a compound with the following structure ##STR00061##

8. The OLED according to claim 1, wherein the concentration of the host material is 20-99.9% of the whole light emitting layer in weight, the concentration of the guest material is 0.01-80% of the whole light emitting layer in weight.

9. The OLED according to claim 8, wherein the concentration of the host material is 80-99% of the whole light emitting layer in weight, the concentration of the guest material is 1-20% of the whole light emitting layer in weight.

10. The OLED according to claim 9, wherein the host material is a compound with structure (I) and concentration of 90-99% of the whole light emitting layer in weight; the concentration of guest material is 1-10% of the whole light emitting layer in weight, the guest material is naphthalene compounds, pyrene compounds, fluorene compounds, phenanthrene compounds, chrysene compounds, fluoranthene compounds, anthracene compounds, dibenzanthracene compounds, perylene compound, bi-aryl vinyl compounds, triphenylamine vinyl compounds, amine compounds, benzimidazole compounds, furan compounds and organic metal chelate compounds.

11. The OLED according to claim 9, wherein the guest material is ##STR00062## the red light emitting zone in the light emitting layer is 590-750 nm; or, the guest material is ##STR00063## the green light emitting zone in the light emitting layer is 490-580 nm.

12. The OLED according to claim 9, wherein the compound with structure (I) is located in hole injection layer, hole transport layer, electron transport layer and/or electron injection layer.

13. The OLED according to claim 2, wherein the concentration of the host material is 20-99.9% of the whole light emitting layer in weight, the concentration of the guest material is 0.01-80% of the whole light emitting layer in weight.

14. The OLED according to claim 3, wherein the concentration of the host material is 20-99.9% of the whole light emitting layer in weight, the concentration of the guest material is 0.01-80% of the whole light emitting layer in weight.

15. The OLED according to claim 4, wherein the concentration of the host material is 20-99.9% of the whole light emitting layer in weight, the concentration of the guest material is 0.01-80% of the whole light emitting layer in weight.

16. The OLED according to claim 5, wherein the concentration of the host material is 20-99.9% of the whole light emitting layer in weight, the concentration of the guest material is 0.01-80% of the whole light emitting layer in weight.

17. The OLED according to claim 6, wherein the concentration of the host material is 20-99.9% of the whole light emitting layer in weight, the concentration of the guest material is 0.01-80% of the whole light emitting layer in weight.

18. The OLED according to claim 7, wherein the concentration of the host material is 20-99.9% of the whole light emitting layer in weight, the concentration of the guest material is 0.01-80% of the whole light emitting layer in weight.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] FIG. 1 is a structural charge of the device, of which, 10 denotes a glass substrate, 20 denotes an anode, 30 denotes hole injection layer, 40 denotes hole transport layer, 50 denotes light emitting layer, 60 denotes electron transport layer, 70 denotes electron injection layer, 80 denotes cathode.

[0028] FIG. 2 is the .sup.1H NMR diagram of compound 89.

[0029] FIG. 3 is the .sup.13C NMR diagram of compound 89.

[0030] FIG. 5 is the TGA map of compound 89.

[0031] FIG. 6 shows the voltage-current density curves of Embodiments 4 and 5.

[0032] FIG. 7 shows the voltage-current density curves of Embodiments 6 and 7.

[0033] FIG. 8 shows the brightnesscurrent efficiency curves of Embodiments 4 and 5.

[0034] FIG. 9 shows the brightnesscurrent efficiency curves of Embodiments 6 and 7.

[0035] FIG. 10 shows the light-emitting spectra of Embodiments 4 and 5.

[0036] FIG. 11 shows the light-emitting spectra of Embodiments 6 and 7.

[0037] FIG. 12 shows the light-emitting spectra of Comparative Examples 1 and 2.

DETAILED DESCRIPTIONS OF THE PREFERRED EMBODIMENTS

[0038] In the following, the present invention is described in details by combining the following examples.

Embodiment 1

[0039] ##STR00032## ##STR00033##

Synthesis of Intermediate 1c

[0040] Add 1a (240.00 g, 0.88 mol), 1b (496.32 g, 1.76 mol), Pd(PPh.sub.3).sub.4 (20.35 g, 17.60 mmol), potassium carbonate (302.52 g, 2.20 mol), toluene (2400 mL), pure water (1200 mL) to a reaction flask. Start to heat after extracting air for three times, and when the reaction solution temperature reaches 95-105V, maintain it for 8-12 h; take samples for TLC and HPLC, to completely react. Stop heating and cool down to 20-30 C., perform suction filtration to separate the organic layer from filtrate. Extract the aqueous layer with ethyl acetate, combine the organic layer, then wash with water, dry by anhydrous magnesium sulfate, and perform suction filtration, to get the filtrate. Concentrate the filtrate to get a dark yellow solid crude product. The crude product is recrystallized from petroleum ether to get an off-white solid product, with a yield of 90% and a purity of 95%.

Synthesis of Intermediate 1d

[0041] Add 1c (302 g, 0.78 mol), B(OEt).sub.3 (142 g, 0.97 mol), n-BuLi/THF (1.6 M, 600 mL), and anhydrous THF (3000 mL) at appropriate ratio to a reaction flask. After extracting with nitrogen for three times, cool down until the reaction solution temperature is 7565 C., slowly add n-BuLi/THF solution dropwise and control the temperature at 7565 C.; after dripping, continue to maintain this temperature for reaction 0.5-1 h. Then add appropriate amount of B(OEt).sub.3 dropwise, to control the reaction solution temperature at 7565 C., after dripping, continue to maintain this temperature for reaction 0.5-1 h. Then transfer the solution to room temperature for naturally heating reaction 4-6 h, then add 2M dilute hydrochloric acid to adjust the PH value to 2-3, after stirring about 1 h, stop the reaction. Add ethyl acetate to extract the solution, and the aqueous layer is extracted by EA. The organic layers are combined and dried over anhydrous magnesium sulfate, then suction filtration is conducted. The filtrate is concentrated to get an off-white solid product, with a purity of 95% and a yield of 62.5%.

Synthesis of Intermediate 1f

[0042] Add 1d (150 g, 0.43 mol), 1e (500 g, 0.86 mol), Pd(PPh.sub.3).sub.4 (5.0 g, 0.44 mmol), potassium carbonate (130 g, 0.92 mol), toluene (1000 mL), pure water (500 mL) to a reaction flask. Start to heat after extracting nitrogen for three times, and when the reaction solution temperature reaches 95-105 C., maintain it for 8-12 h; take samples for TLC and HPLC, to completely react. Stop heating and cool down to 20-30 C., perform suction filtration to separate the organic layer from filtrate. Extract the aqueous layer with ethyl acetate, combine the organic layers, dry by anhydrous magnesium sulfate, and perform suction filtration. The filtrate is concentrated to get dark yellow solid crude product, with a purity of 80% and a yield of 78.1%.

Synthesis of Intermediate 1 g

[0043] Add 1f (210 g, 0.42 mol), NBS (135 g, 0.71 mol), DMF (5 L) to a reaction flask. Start to heat after extracting nitrogen for three times, and when the reaction solution temperature reaches 60-65V, maintain it for 6-8 h; take samples for TLC and HPLC, to completely react. Stop heating and cool down to 20-30 C., then pour the reaction solution to ice-water to separate dark yellow solid, and then perform suction filtration to get yellow solid and bake to obtain 1 g of crude product. Add the crude product to DCM/MeOH until the solution becomes slightly turbid, continue to stir for about 30 min, to separate out a large amount of solid, then perform suction filtration to get pale yellow solid product, with a yield of approximate 54.05% and a purity of 98.5%.

[0044] .sup.1H NMR (300 MHz, CDCl.sub.3) 8.64 (d, J=8.8 Hz, 2H), 7.99-7.90 (m, 4H), 7.87 (t, J=1.6 Hz, 1H), 7.78 (dd, J=9.3, 2.3 Hz, 6H), 7.61 (ddd, J=8.8, 6.5, 1.1 Hz, 2H), 7.56-7.48 (m, 6H), 7.46-7.38 (m, 4H).

[0045] .sup.13C NMR (76 MHz, CDCl.sub.3) 142.67 (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

[0046] Add 1 g (9.5 g, 16.92 mmol), 1 h (6.41 g, 30.51 mmol), Pd(PPh.sub.3).sub.4 (1.5 g, 1.3 mmol), potassium carbonate (5.84 g, 42.3 mmol), toluene (150 mL) and pure water (75 mL) to a 500 ml three-necked flask. After extracting nitrogen for three times, reaction occurs at 105 C. The time of reaction stop is around 12 h, which is detected by liquid phase. The reaction solution is earth yellow of catalyst at the beginning, slowly turning into a yellow solution. After reaction stops, the upper layer is bright and light yellow, and the lower layer is water. After reaction stops, filter the solution, wash the filter residues with ethyl acetate until no product in the residue, then collect the filtrate, spin-dry, to separate out a large amount of off white solid. Collect the filter residue to dry, to get the target product, with purity of 98%; after vacuum sublimation, gray-white solid powder with purity of 99.5% is obtained.

[0047] .sup.1H-NMR (300 MHz, CDCl.sub.3) 8.10-8.21 (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).

Embodiment 2

Synthesis of Compound 3

[0048] ##STR00034##

[0049] Add 1 g (9.5 g, 16.92 mmol), 3a (7.25 g, 30.46 mmol), Pd(PPh.sub.3).sub.4 (1.5 g, 1.3 mmol), potassium carbonate (5.84 g, 42.3 mmol), toluene (150 mL) and pure water (75 mL) to a 500 ml three-necked flask. After extracting nitrogen for three times, reaction occurs at 105 C. The time of reaction stop is around 12 h, which is detected by liquid phase. The reaction solution is earth yellow of catalyst at the beginning, slowly turning into a yellow solution. After reaction stops, the upper layer is bright and light yellow, and the lower layer is water. After reaction stops, filter the solution, wash the filter residues with ethyl acetate until no product in the residue, then collect the filtrate, spin-dry, to separate out a large amount of off white solid. Collect the filter residue to dry, to get the target product, with purity of 98%; after vacuum sublimation, gray-white solid powder with purity of 99.7% is obtained.

[0050] .sup.1H-NMR (300 MHz, CDCl.sub.3) 8.1-8.2 (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).

Embodiment 3

Synthesis of Compound 89

[0051] ##STR00035##

[0052] Add 1 g (10.0 g, 17.8 mmol), 89a (7.1 g, 19.6 mmol), Pd(PPh.sub.3).sub.4 (432.2 mg, 0.35 mmol), K2CO3 (6.14 g, 44.5 mmol), toluene (300 mL) and water (150 mL) successively to a reaction tank. After deoxygenization of the device and introduction of nitrogen, heat to 100 V for reaction overnight, apply to the plates at a ratio of DCM:PE=1:5. The product gives out intensive blue light under UV light at 365 nm wavelength, with the Rf value at about 0.2. Perform suction filtration with the reaction solution, wash the filter cake with ethyl acetate (100 mL) twice and separate. Extract the aqueous layer with ethyl acetate (100 mL) once, combine the organic layers, then wash the organic layer once with water (200 mL). spin dry to remove the solvent. The crude product is recrystallized from 120 ml DCM/MeOH, then suction filtration is performed to get 13.1 g yellow solid powder, with a purity of 98.7% and a yield of 92.2% yield. After vacuum sublimation, a slight yellow solid powder with purity of 99.7% is obtained. m/z=797.

[0053] As shown from FIG. 2 and FIG. 3, the hydrogen spectra and carbon spectra of compound 89 are completely consistent with the structures. From the high performance liquid chromatogram of compound 89 in FIG. 4, the product made by the synthesis method in the invention has high purity. According to the thermal gravametric analysis of compound 89 in FIG. 5, the decomposition temperature of this type of compound is higher than 400 degrees centigrade, indicating that it has very high thermal stability.

Embodiment 4

Preparation of OLED1

Prepare OLED by the Organic Electronic Material in the Present Invention

[0054] Firstly, the ITO transparent conductive glass substrate 10 (with anode 20 above) is washed with detergent solution and deionized water, ethanol, acetone, deionized water in sequence, then treated with oxygen plasma for 30 seconds.

[0055] Then, perform vacuum evaporation of 10 nm HAT-CN6 in ITO, which is used as the hole injection layer 30.

[0056] Then, perform vacuum evaporation of NPB, to form 30 nm thick of hole transport layer 40.

[0057] Then, perform vacuum evaporation of 30 nm thick of compound C545T (2%) and compound 3(98%) in hole transport layer, which is used as light emitting layer 50.

[0058] And then, perform vacuum evaporation of 15 nm thick of TPBi in light emitting layer, which is used as electron transport layer 60.

[0059] Finally, perform vacuum evaporation of 15 nm BPhen:Li as electron injection layer 70, and vacuum evaporation of 150 nm Al as the device cathode 80.

[0060] The voltage of the device made in 20 mA/cm.sup.2 of operating current density is 5.57 V, the current efficiency is 7.26 cd/A under the brightness of 1000 cd/m.sup.2. The peak value of green light emitting is 500 nm.

[0061] The said structural formula of the device

##STR00036##

Embodiment 5

Preparation of OLED2

[0062] Procedures are the same as Embodiment 4. OLED is made using compound 89 instead of compound 3.

[0063] The voltage of the device made in 20 mA/cm.sup.2 of operating current density is 5.73 V, the current efficiency is 7.81 cd/A under the brightness of 1000 cd/m.sup.2. The peak value of green light emitting is 504 nm.

Embodiment 6

Preparation of OLED3

[0064] The procedures are the same as Embodiment 4. OLED is made using the compound DCJTB instead of compound C545T.

[0065] The voltage of the device made in 20 mA/cm.sup.2 of operating current density is 7.54 V, the current efficiency is 4.24 cd/A under the brightness of 1000 cd/m.sup.2. The peak value of red light emitting is 592 nm.

Embodiment 7

Preparation of OLED4

[0066] Procedures are the same as Embodiment 6. OLED is made using compound 89 instead of compound 3.

[0067] The voltage of the device made in 20 mA/cm.sup.2 of operating current density is 8.23 V, the current efficiency is 3.65 cd/A under the brightness of 1000 cd/m.sup.2. The peak value of red light emitting is 600 nm.

Comparative Example 1

Preparation of OLED 5

[0068] The procedures are the same as Embodiment 4. OLED is made using 100% of compound 3 as the light emitting layer 50 for comparison.

[0069] The peak value of blue light emitting for the prepared OLED is 448 nm.

Comparative Example 2

Preparation of OLED6

[0070] The procedures are the same as Embodiment 4. OLED is made using 100% of compound 89 as the light emitting layer 50 for comparison.

[0071] The peak value of blue light emitting for the prepared OLED is 448 nm.

[0072] The embodiments 4,5,6,7 are the specific applications of the material in the present invention. The prepared devices 1 and 2 emit green light, and the prepared devices 3 and 4 emit red light, with excellent efficiency and brightness. By comparing the light-emitting spectra of embodiments 4 and 6 with those of the Comparative Example 1, the energy transfer from the host material to the guest material is very effective. Similarly, the comparison between embodiments 5,7 and the Comparative Example 2 also shows excellent effect. Therefore, as stated above, the material in the present invention has high stability, and the OLED made in the invention has high efficiency and light purity.