Light extraction layer compound containing trifluoromethane and organic electroluminescent device thereof

Abstract

The invention belongs to the technical field of organic electroluminescent materials, and particularly relates to a trifluoromethane-containing light extraction layer compound and an organic electroluminescent device thereof. According to the light extraction layer compound containing trifluoromethane, at least two substitution sites of triazine are substituted by biphenyl, and compared with single benzene substitution, the refractive index of the series of compounds can be further reduced. Meanwhile, the melting point of the series of compounds with the terminal meta-substituted trifluoromethane benzene structure is reduced, so that the series of compounds are in a glassy state during sublimation during preparation of the organic electroluminescent device, and the problem that equipment is blocked and materials are unavailable is prevented.

Description

Technical Field

[0001] The present invention belongs to the technical field of organic electroluminescent materials, and particularly relates to a light extraction layer compound containing trifluoromethane and an organic electroluminescent device. Background Art

[0002] Organic Light-Emitting Diode (OLED) is an electroluminescent device based on organic semiconductor materials. Its core principle is that holes and electrons are respectively injected into the light-emitting layer from the anode and cathode by applying an external electric field. During the recombination process, excitons are formed and accompanied by light radiation, thereby realizing the efficient conversion of electrical energy into light energy. Compared with traditional display technologies, OLEDs have significant advantages such as ultra-thinness, low driving voltage, high brightness, wide color gamut, and flexibility, and have become the key development direction of the new generation of display and lighting technologies.

[0003] In terms of device structure optimization, the top-emission structure (Top-Emission OLED) has become the mainstream technical direction in the industry in recent years. This structure uses high work function metals (such as Ag, Al, etc.) as the anode and is paired with a semi-transparent cathode (such as a LiF / Al / Ag, Ca / Mg, or LiF / MgAg composite electrode). By extracting light from the top of the device, it avoids the occlusion of the light-emitting area by the pixel circuit in the bottom-emission structure, thus significantly improving the aperture ratio and emission uniformity. However, affected by the refractive index mismatch between multiple film layers, when the light generated by the light-emitting layer is transmitted to the cathode interface, total internal reflection occurs when the incident angle exceeds the critical angle, resulting in more than 70% of the light being confined inside the device and unable to be effectively extracted, seriously restricting the improvement of the Light-Out-Coupling Efficiency (LOCE).

[0004] To address the above optical loss problem, researchers have proposed to optimize the light transmission path by introducing the capping layer technology. Early studies have shown that setting a single high refractive index capping layer (such as ZnS, TiO2, etc.) between the light-emitting layer and the semi-transparent electrode can enhance the microcavity effect. However, limited by the refractive index regulation range of the material, the efficiency improvement is limited. In recent years, the dual capping layer structure has become a research hotspot. This technology inserts a low refractive index material layer between the high refractive index capping layer and the light-emitting layer to construct a dual resonance cavity structure, and uses the multi-level optical path interference effect to further broaden the light extraction angle and optimize the emission spectrum distribution. For example, by adjusting the thickness and refractive index of the low refractive layer, the light extraction efficiency can be significantly increased by more than 30%.

[0005] However, the development of low-refractive-index materials still faces severe challenges. In the prior art, low-refractive-index materials mainly include two categories: one is inorganic fluorides (such as LiF, MgF2), but they need to be evaporated at high temperatures (>300 °C), which conflicts with the thermal sensitivity characteristics of organic functional layers, and defects are likely to occur at the inorganic / organic interface, resulting in an increase in non-radiative recombination of carriers; the other is long-chain alkane organic compounds, but their thermal stability is poor and they are easily decomposed during high-temperature evaporation, making it difficult to form a uniform and dense thin film. In addition, both have problems such as poor process compatibility and uncontrollable film quality, which limit the practical application of the double-coverage layer technology.

[0006] Therefore, it is urgent to develop a vapor-depositable low-refractive-index covering layer material with good evaporation stability and excellent film quality to obtain high-efficiency and long-life OLED devices. Summary of the Invention

[0007] To solve the problems in the background art, the first object of the present invention is to provide a light extraction layer compound containing trifluoromethane, and the technical solution is as follows:

[0008] A light extraction layer compound containing trifluoromethane, whose structure is shown in general formula I:

[0009]

[0010] L is selected from a single bond, a substituted or unsubstituted C6-C 30 arylene group;

[0011] R1 to R9 are each independently selected from hydrogen, deuterium, F, cyano group, CF3, C l -C 24 alkane group, C3-C 20 cycloalkane group, substituted or unsubstituted C6-C 30 aryl group; `

[0012] When there are substituents, the substituents are selected from hydrogen, deuterium, F, cyano group, CF3, C l -C 24 alkane group, C3-C 20 cycloalkane group, C6-C 30 aryl group.

[0013] As a preference of the present invention, when L is selected from arylene groups, it is selected from phenylene group and biphenylene group.

[0014] As a preference of the present invention, R1 to R9 are each independently selected from hydrogen, deuterium, F, cyano group, CF3, C l -C8 alkane group, C3-C6 cycloalkane group, C6-C 18 aryl group.

[0015] Preferably in the present invention, each of R1 to R9 is independently selected from hydrogen, CF3, C l -C8 alkyl, C6-C 18 aryl.

[0016] Preferably in the present invention, each of R1 to R9 is independently selected from hydrogen, CF3, methyl, isopropyl, tert-butyl, phenyl.

[0017] Preferably in the present invention, the compound of general formula I is selected from one of the following structures:

[0018]

[0019]

[0020]

[0021]

[0022]

[0023]

[0024]

[0025]

[0026]

[0027]

[0028] Another object of the present invention is to provide an organic electroluminescent device, including a cathode and an anode disposed opposite to each other, and an organic layer disposed between the cathode and the anode, further including a light extraction layer disposed on the cathode, and the light extraction layer is prepared by the above-mentioned light extraction material.

[0029] Preferably in the present invention, the organic electroluminescent device is applied in a display device, and the display device is a mobile phone display screen, a computer display screen, a television display screen, a smart watch display screen, a smart car display panel, a VR or AR helmet display screen, a display screen of various smart devices.

[0030] The beneficial effects of the present invention are as follows:

[0031] The light extraction layer compound containing trifluoromethane provided by the present invention, wherein at least two substitution sites of triazine are substituted by biphenyl, can further reduce the refractive index of this series of compounds compared with monobenzene substitution. At the same time, this series of compounds with a trifluoromethane benzene structure having a meta substitution at the end has a reduced melting point, making this series of compounds in a glass state during the sublimation of preparing organic electroluminescent devices, preventing the problem of material unavailability due to device pore blockage. Detailed implementation manners

[0032] Next, the technical solutions of the present invention will be clearly and completely described in conjunction with the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0033] For those not indicating specific conditions in the embodiments, they are carried out according to conventional conditions or the conditions recommended by the manufacturer. For the reagents or instruments not indicating the manufacturer, they are all conventional products that can be obtained through commercial purchase. Some reaction compounds are purchased from commercial suppliers (Zhengzhou Alpha Chemical Co., Ltd.), and some compounds that cannot be directly purchased are prepared by simple reactions from commercially purchased raw materials. Percentages are all by mass percentage, and the temperature is in degrees Celsius (°C). Such method principles, operation processes, conventional post-treatments, passing through silica gel columns, recrystallization purification and other means are well-known to synthetic personnel in this field and can fully realize the synthesis process to obtain the target product. The reactions in each preparation example are generally carried out under a positive pressure of nitrogen or argon.

[0034] Preparation examples

[0035] Example 1: Preparation of Compound 1

[0036]

[0037] Synthesis of 1-2: 1-1 (2.3 g, 7.2 mmol), bis(pinacolato)diboron (1.8 g, 7.2 mmol), potassium acetate (KOAC) (4.7 g, 48 mmol) and [1,1'-bis(diphenylphosphino)ferrocene]dichloropalladium (Pd(dppf)2Cl2) (0.13 g, 0.18 mmol) were added into a dry reaction flask equipped with a condenser. After performing the evacuation and nitrogen filling operation for more than three times, they were dissolved in 200 mL of dry 1,4-dioxane. Subsequently, the temperature was raised to 100 °C and the reaction was carried out for 12 h. After the reaction was completed, the reaction mixture was poured into water, and the aqueous phase was extracted three times with dichloromethane (500 mL). The obtained dichloromethane phase was washed once with water and then dried over anhydrous sodium sulfate. After removing dichloromethane by distillation under reduced pressure, the crude product was washed twice with methanol to obtain 1-2 (1.5 g, 51%);

[0038] Synthesis of Compound 1: 1-2 (12.5 g, 30 mmol) and 1-3 (3.4 g, 15 mmol) were completely dissolved in tetrahydrofuran (THF) (100 mL), and 2M aqueous potassium carbonate solution (60 mL) and tetrakis(triphenylphosphine)palladium (Pd(PPh3)4) (1.2 g, 1.0 mmol) were added thereto. The mixture was heated and stirred for 6 h. Then, the mixture was cooled to room temperature to complete the reaction. After removing the potassium carbonate solution, the solid was filtered out and washed once with ethanol to obtain Compound 1 (10.1 g, 92%), MS: 733.30.

[0039] Example 2: Preparation of Compound 2

[0040]

[0041] Compound 2 was synthesized in the same manner as Compound 1, except that 2-1 was used instead of 1-3, MS: 869.23.

[0042] Example 3: Preparation of Compound 3

[0043]

[0044] 3-2 was synthesized in the same manner as 1-2, except that 3-1 was used instead of 1-1;

[0045] Compound 3 was synthesized in the same manner as Compound 1, except that 3-2 was used instead of 1-2 and 2-1 was used instead of 1-3, MS: 1004.69.

[0046] Example 4: Preparation of Compound 4

[0047]

[0048] Synthesis of 4-1: 2-1 (5.4 g, 15 mmol) and 1-2 (6.2 g, 15 mmol) were completely dissolved in tetrahydrofuran (THF) (50 mL), and an aqueous solution of 2M potassium carbonate (30 mL) and tetrakis(triphenylphosphine)palladium (Pd(PPh3)4) (0.6 g, 0.5 mmol) were added thereto. The mixture was heated and stirred for 6 h. Then, the mixture was cooled to room temperature to complete the reaction. After removing the potassium carbonate solution, the solid was filtered out and washed once with ethanol to obtain 4-1 (8.3 g, 90%);

[0049] Synthesis of Compound 4: 4-1 (9.2 g, 15 mmol) and 3-2 (7.3 g, 15 mmol) were completely dissolved in tetrahydrofuran (THF) (50 mL), and an aqueous solution of 2M potassium carbonate (30 mL) and tetrakis(triphenylphosphine)palladium (Pd(PPh3)4) (0.6 g, 0.5 mmol) were added thereto. The mixture was heated and stirred for 6 h. Then, the mixture was cooled to room temperature to complete the reaction. After removing the potassium carbonate solution, the solid was filtered out and washed once with ethanol to obtain Compound 4 (12.8 g, 91%), MS: 937.23.

[0050] Example 5: Preparation of Compound 16

[0051]

[0052] The synthesis method of 16-2 is the same as that of 1-2, except that 16-1 is used to replace 1-1;

[0053] The synthesis method of Compound 16 is the same as that of Compound 1, except that 16-2 is used to replace 1-2, MS: 817.37.

[0054] Example 6: Preparation of Compound 18

[0055]

[0056] The synthesis method of 18-2 is the same as that of 1-2, except that 18-1 is used to replace 1-1;

[0057] The synthesis method of Compound 18 is the same as that of Compound 1, except that 18-2 is used to replace 1-2 and 18-3 is used to replace 1-3, MS: 957.25.

[0058] Example 7: Preparation of Compound 23

[0059]

[0060] The synthesis method of 23-2 is the same as that of 1-2, except that 23-1 is used to replace 1-1;

[0061] The synthesis method of Compound 23 is the same as that of Compound 1, except that 1-2 is replaced by 23-2, MS: 885.34.

[0062] Example 8: Preparation of Compound 28

[0063]

[0064] The synthesis method of 28-2 is the same as that of 4-1, except that 2-1 is replaced by 28-1;

[0065] The synthesis method of Compound 28 is the same as that of Compound 4, except that 4-1 is replaced by 28-2, 3-2 is replaced by 23-2, MS: 837.31.

[0066] Example 9: Preparation of Compound 31

[0067]

[0068] The synthesis method of Compound 31 is the same as that of Compound 1, except that 1-2 is replaced by 23-2, 1-3 is replaced by 18-3, MS: 997.48.

[0069] Example 10: Preparation of Compound 35

[0070]

[0071] The synthesis method of 35-2 is the same as that of 1-2, except that 1-1 is replaced by 25-1;

[0072] The synthesis method of Compound 35 is the same as that of Compound 1, except that 1-2 is replaced by 35-2, 1-3 is replaced by 2-1, MS: 1077.35.

[0073] Example 11: Preparation of Compound 44

[0074]

[0075]

[0076] The synthesis method of 44-2 is the same as that of 1-2, except that 1-1 is replaced by 44-1;

[0077] The synthesis method of 44-3 is the same as that of 4-1, except that 2-1 is replaced by 1-3;

[0078] The synthesis method of Compound 44 is the same as that of Compound 4, except that 4-1 is replaced by 44-3, 3-2 is replaced by 44-2, MS: 945.32.

[0079] Example 12: Preparation of Compound 48

[0080]

[0081] Compound 48 was synthesized in the same manner as Compound 4, except that 28-2 was used instead of 4-1, and 44-2 was used instead of 3-2. MS: 973.31.

[0082] Example 13: Preparation of Compound 54

[0083]

[0084] Compound 54-2 was synthesized in the same manner as 1-2, except that 54-1 was used instead of 1-1;

[0085] Compound 54 was synthesized in the same manner as Compound 4, except that 44-3 was used instead of 4-1, and 54-2 was used instead of 3-2. MS: 893.37.

[0086] Example 14: Preparation of Compound 67

[0087]

[0088] Compound 67-2 was synthesized in the same manner as 1-2, except that 67-1 was used instead of 1-1;

[0089] Compound 67 was synthesized in the same manner as Compound 1, except that 67-2 was used instead of 1-2, and 28-1 was used instead of 1-3. MS: 1137.32.

[0090] Example 15: Preparation of Compound 73

[0091]

[0092] Compound 73 was synthesized in the same manner as Compound 1, except that 73-1 was used instead of 1-3. MS: 809.31.

[0093] Example 16: Preparation of Compound 74

[0094]

[0095] Compound 74 was synthesized in the same manner as Compound 1, except that 74-1 was used instead of 1-3. MS: 945.32.

[0096] Example 17: Preparation of Compound 88

[0097]

[0098] The synthesis method of 88-2 is the same as that of 4-1, except that 88-1 is used to replace 2-1 and 18-2 is used to replace 1-2;

[0099] The synthesis method of compound 88 and compound 4 is the same, except that 88-2 is used to replace 4-1, 16-2 is used to replace 3-2, MS: 1059.47.

[0100] Example 18: Preparation of compound 94

[0101]

[0102] The synthesis method of 94-2 is the same as that of 1-2, except that 94-1 is used to replace 1-1;

[0103] The synthesis method of 94-4 is the same as that of 4-1, except that 94-3 is used to replace 2-1 and 94-2 is used to replace 1-2;

[0104] The synthesis method of compound 94 and compound 4 is the same, except that 94-4 is used to replace 4-1, 16-2 is used to replace 3-2, MS: 1045.18.

[0105] Example 19: Preparation of compound 102

[0106]

[0107] The synthesis method of 102-2 is the same as that of 4-1, except that 102-1 is used to replace 2-1;

[0108] The synthesis method of compound 102 and compound 4 is the same, except that 102-2 is used to replace 4-1, 23-2 is used to replace 3-2, MS: 927.38.

[0109] Example 20: Preparation of compound 108

[0110]

[0111] The synthesis method of 108-2 is the same as that of 4-1, except that 108-1 is used to replace 2-1;

[0112] The synthesis method of compound 108 and compound 4 is the same, except that 108-2 is used to replace 4-1, 35-2 is used to replace 3-2, MS: 981.36.

[0113] Example 21: Preparation of compound 115

[0114]

[0115] The synthesis method of Compound 115 is the same as that of Compound 1, except that 44-2 is used to replace 1-2, 73-1 is used to replace 1-3, MS: 1233.02.

[0116] Example 22: Preparation of Compound 125

[0117]

[0118] The synthesis method of Compound 125 is the same as that of Compound 1, except that 54-2 is used to replace 1-2, 73-1 is used to replace 1-3, MS: 1129.55.

[0119] Example 23: Preparation of Compound 136

[0120]

[0121] The synthesis method of 136-1 is the same as that of 4-1, except that 73-1 is used to replace 2-1;

[0122] The synthesis method of Compound 136 is the same as that of Compound 4, except that 136-1 is used to replace 4-1, 67-2 is used to replace 3-2, MS: 997.48.

[0123] Example 24: Preparation of Compound 145

[0124]

[0125] The synthesis method of Compound 145 is the same as that of Compound 1, except that 145-1 is used to replace 1-3, MS: 809.31.

[0126] Example 25: Preparation of Compound 150

[0127]

[0128] The synthesis method of Compound 150 is the same as that of Compound 1, except that 16-2 is used to replace 1-2, 145-1 is used to replace 1-3, MS: 893.53.

[0129] Example 26: Preparation of Compound 159

[0130]

[0131] The synthesis method of 159-1 is the same as that of 4-1, except that 145-1 is used to replace 2-1;

[0132] The synthesis method of Compound 159 is the same as that of Compound 4, except that 159-1 is used to replace 4-1, 54-2 is used to replace 3-2, MS: 969.18.

[0133] Example 27: Preparation of Compound 166

[0134]

[0135] Compound 166 was synthesized in the same manner as Compound 1, except that 3-2 was used to replace 1-2, 166-1 was used to replace 1-3, MS: 1080.95.

[0136] Example 28: Preparation of Compound 177

[0137]

[0138] Compound 177-1 was synthesized in the same manner as Compound 4-1, except that 166-1 was used to replace 2-1;

[0139] Compound 177 was synthesized in the same manner as Compound 4, except that 177-1 was used to replace 4-1, 35-2 was used to replace 3-2, MS: 1049.35.

[0140] Example 29: Preparation of Compound 181

[0141]

[0142] Compound 181-1 was synthesized in the same manner as Compound 4-1, except that 145-1 was used to replace 2-1, 94-2 was used to replace 1-2;

[0143] Compound 181 was synthesized in the same manner as Compound 4, except that 181-1 was used to replace 4-1, 16-2 was used to replace 3-2, MS: 865.41.

[0144] Example 30: Preparation of Compound 185

[0145]

[0146] Compound 186 was synthesized in the same manner as Compound 1, except that 185-1 was used to replace 1-3, MS: 809.06.

[0147] Example 31: Preparation of Compound 199

[0148]

[0149] Compound 199-1 was synthesized in the same manner as Compound 4-1, except that 185-1 was used to replace 2-1;

[0150] Compound 199 was synthesized in the same manner as Compound 4, except that 199-1 was used to replace 4-1, 54-2 was used to replace 3-2, MS: 969.45.

[0151] Example 32: Preparation of Compound 207

[0152]

[0153] The synthesis method of 207-2 is the same as that of 4-1, except that 207-1 is used to replace 2-1;

[0154] The synthesis method of Compound 207 is the same as that of Compound 4, except that 207-2 is used to replace 4-1, MS: 1013.24.

[0155] Example 33: Preparation of Compound 211

[0156]

[0157] The synthesis method of Compound 211 is the same as that of Compound 4, except that 207-2 is used to replace 4-1 and 16-2 is used to replace 3-2, MS: 987.32.

[0158] Example 34: Preparation of Compound 213

[0159]

[0160] The synthesis method of Compound 213 is the same as that of Compound 4, except that 207-2 is used to replace 4-1 and 18-2 is used to replace 3-2, MS: 1001.10.

[0161] Example 35: Preparation of Compound 221

[0162]

[0163] The synthesis method of 221-1 is the same as that of 4-1, except that 185-1 is used to replace 2-1 and 94-2 is used to replace 1-2;

[0164] The synthesis method of Compound 221 is the same as that of Compound 4, except that 221-1 is used to replace 4-1 and 16-2 is used to replace 3-2, MS: 865.37.

[0165] In addition, it should be noted that other compounds of the present application can be obtained by referring to the preparation methods of the above-listed examples, so they will not be listed one by one here.

[0166] Evaluation of the optical properties of the compound:

[0167] To prepare the single-layer film for optical property evaluation, the specific compound and Compound Ref were respectively used to fabricate evaporation films with a thickness of 80 nm on a silicon substrate, and the refractive index n and extinction coefficient k values at wavelengths of 460 nm, 530 nm, and 620 nm were measured. The measured data are shown in Table 1 below. Compound Ref is a known low-refractive-index material.

[0168] Table 1

[0169]

[0170]

[0171] Device embodiments

[0172] Performance evaluation of the device:

[0173] The following are several application examples of the low-refractive-index compounds described in the present invention applied to OLED devices to further illustrate the beneficial effects of the compounds of the present invention. The materials used in the examples were purchased commercially or synthesized by themselves.

[0174] Preparation of OLED device: Using an ultrasonic cleaner, the top-emitting substrate was washed with isopropyl alcohol, acetone, and distilled water for 15 minutes each, and then subjected to a 30-minute UV ozone washing treatment in air. The treated substrate was subjected to vacuum evaporation to deposit a hole injection layer (HT:HI, 10 nm, 2%), a hole transport layer (HT, 100 nm), a light-emitting auxiliary layer (B-prime, 5 nm), a blue light-emitting layer (host material:doping material = Compound BH:Compound BD (weight ratio 97:3, 30 nm), a hole blocking layer (HB, 5 nm), an electron transport layer (Compound ET:Liq = 1:1, 30 nm), and an electron injection layer (Yb, 1 nm) in sequence. After co-evaporation of Mg and Ag (weight ratio 1:9, 20 nm) to form a semi-transparent cathode, then CPL-L (20 nm) was evaporated as a low-refractive-index covering layer, and CPL-H (50 nm) was evaporated as a high-refractive-index covering layer, and the two formed a double-covering layer structure. Then, a coating device was used to coat the cleaned cover plate with UV glue, and then the coated cover plate was moved to the lamination section. The evaporated substrate was placed on top of the cover plate, and finally, the substrate and the cover plate were laminated under the action of a laminating device to complete the photo-curing of the UV glue.

[0175] Structure of the OLED device:

[0176] ITO:Ag:ITO / HT:HI(2%, 10 nm) / HT(100 nm) / B-prime(5 nm) / BH:BD(97:3, 30 nm) / HB(5 nm) / ET:Liq(50:50) / Yb(1 nm) / Mg:Ag(1:9, 20 nm) / CPL-L(20 nm) / CPL-H(50 nm).

[0177] In the device examples and comparative examples, the CPL-Ls respectively adopt the corresponding compounds in Table 2 below.

[0178] It should be noted that the high refractive index covering layer materials used in this example are only exemplary and do not serve as special limitations of the present invention on the high refractive index covering layer materials. The molecular structural formulas of the related materials are shown as follows (particularly preferably selected from the following structures, but it does not mean that the present invention is limited to the following structures):

[0179]

[0180] The driving voltages, BI values, and luminous efficiencies of the organic electroluminescent devices obtained from the above device examples and device comparative examples were characterized at a brightness of 1000 (nits), and the test results are shown in Table 2 below.

[0181]

[0182]

[0183] In the blue top-emitting device, the luminous efficiency is greatly affected by chromaticity. Therefore, considering the influencing factor of chromaticity on efficiency, the ratio of luminous efficiency to CIEy is defined as the BI value, that is, BI = (cd / A) / CIEy.

[0184] As can be seen from Table 1, the refractive indices of the compounds corresponding to Examples 1 to 35 are lower than that of the comparative compound ref because the series of compounds provided by the present invention have more biphenyl groups than the comparative compound ref; as can be seen from Table 2, the luminous efficiencies of the devices in Device Examples 1 to 35 are better than those of the comparative examples, indicating that the use of the low refractive index covering layer material and the high refractive index covering layer material provided by the present invention can better play the role of light collection and further reduce light loss. At the same time, the series of compounds provided by the present invention have a meta-substituted trifluoromethanobenzene structure at the end, resulting in a lower melting point, making the series of compounds in a glass state during the sublimation for preparing the organic electroluminescent device, preventing the problem of equipment clogging holes and unusable materials.

[0185] The above examples only list the effect data of the devices made of a part of the structural formulas. This is a representative sampling test. Judging from the experimental data, the overall data do not differ much and can represent the effects of other unlisted structures.

[0186] Those skilled in the art will clearly see that, without departing from the spirit and scope of the present invention, the present invention can have many modifications and variations. Therefore, it can be expected that the present invention covers the modifications and variations of the present invention provided within the scope of the appended claims and their equivalents.

[0187] The applicant declares that the present invention illustrates the organic electroluminescent material and the organic electroluminescent device of the present invention through the above embodiments, but the present invention is not limited to the above embodiments, that is, it does not mean that the present invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvement to the present invention, the equivalent substitution of each raw material of the product of the present invention, the addition of auxiliary components, the selection of specific methods, etc., all fall within the protection scope and the disclosure scope of the present invention.

Claims

1. A light extraction layer compound containing trifluoromethane, characterized in that, Its structure is shown in General Formula I: L is selected from a single bond, a substituted or unsubstituted C6-C 30 arylene group; R1 to R9 are each independently selected from hydrogen, deuterium, F, cyano, CF3, C l to C 24 alkyl, C3 to C 20 cycloalkyl, substituted or unsubstituted C6 to C 30 aryl; When there is a substitution, the substituent is selected from hydrogen, deuterium, F, cyano, CF3, C l ~C 24 alkyl, C3-C 20 cycloalkyl, C6-C 30 aryl.

2. The light extraction layer compound containing trifluoromethane according to claim 1, characterized in that, When L is selected from arylene groups, it is selected from phenylene and biphenylene.

3. The light extraction layer compound containing trifluoromethane according to claim 1, wherein Each of R1 to R9 is independently selected from hydrogen, deuterium, F, cyano, CF3, C l ~C8 alkyl, C3~C6 cycloalkyl, C6~C 18 aryl.

4. The light extraction layer compound containing trifluoromethane according to claim 3, wherein, Each of R1 to R9 is independently selected from hydrogen, CF3, C l -C8 alkyl, C6-C 18 aryl.

5. The light extraction layer compound containing trifluoromethane according to claim 4, characterized in that, Each of R1 to R9 is independently selected from hydrogen, CF3, methyl, isopropyl, tert-butyl, and phenyl.

6. The light extraction layer compound containing trifluoromethane according to claim 1, wherein This compound is selected from one of the following structures:

7. An organic electroluminescent device, comprising a cathode and an anode disposed opposite to each other, and an organic layer disposed between the cathode and the anode, characterized in that, It further includes a light extraction layer disposed on the cathode, and the light extraction layer is prepared from the light extraction material according to any one of claims 1-6.

8. The organic electroluminescent device according to claim 7, characterized in that, This organic electroluminescent device is applied in a display device, and the display device is a mobile phone display screen, a computer display screen, a television display screen, a smart watch display screen, a smart car display panel, a VR or AR helmet display screen, or a display screen of various smart devices.

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