Triarylated amine compound containing benzofluorene, preparation method of triarylated amine compound, light-emitting auxiliary material and organic electroluminescent device

Abstract

The invention relates to the technical field of organic electroluminescent devices, in particular to a triarylated amine compound containing benzofluorene, a preparation method of the triarylated amine compound, a light-emitting auxiliary material and an organic electroluminescent device. The structural formula of the triarylated amine compound containing phenyl fluorene is shown as # imgabs0 #, Ar1 represents any one of the groups shown as the following structural formula: # imgabs1 #, and the compound is used as a light-emitting auxiliary layer material, so that the service life of the organic electroluminescent device can be further prolonged under the condition that the efficiency and the driving voltage of the organic electroluminescent device are not influenced.

Description

Technical Field

[0001] The invention relates to the technical field of organic electroluminescent devices, and in particular to triarylamine compounds containing phenylfluorene, preparation methods thereof, luminescent auxiliary materials and organic electroluminescent devices. Background Art

[0002] Organic Light-Emitting Diode (OLED) display technology is different from traditional LCD display. OLED display does not require a backlight, but is made of a very thin light-emitting layer and a glass substrate. The light-emitting layer includes an organic light-emitting layer, an electron injection layer and a hole injection layer. The electron injection layer and the hole injection layer are respectively arranged on the upper and lower sides of the organic light-emitting layer. When current passes through the light-emitting layer, the light-emitting layer will emit light. Since the OLED display method does not require a backlight, the OLED display device can be made lighter and thinner, with a larger viewing angle, and can significantly save electricity. Therefore, OLED display technology is becoming more and more popular.

[0003] However, OLEDs have limited service life and low luminous efficiency. To solve these problems, a luminescent auxiliary layer or multiple hole transport layers are usually added between the hole transport layer and the light-emitting layer. The luminescent auxiliary layer enables holes transferred from the anode to move smoothly to the light-emitting layer, and can block electrons transferred from the cathode, thereby confining the electrons in the light-emitting layer, reducing the potential barrier between the hole transport layer and the light-emitting layer, reducing the driving voltage of the organic electroluminescent device, and further increasing the utilization of holes, thereby improving the luminous efficiency and service life of the device.

[0004] However, there are few materials that can form a luminescent auxiliary layer and have excellent device performance. Therefore, how to provide a luminescent auxiliary material with long life and high luminescent efficiency and its preparation method and organic electroluminescent device is a technical problem that technical personnel in this field urgently need to solve.

[0005] In view of this, the present invention is proposed. Summary of the invention

[0006] The purpose of the present invention is to provide a triarylamine compound containing phenylfluorene, a preparation method thereof, a luminescence auxiliary material and an organic electroluminescent device. The compound is used as a luminescence auxiliary layer material to further improve the life of the organic electroluminescent device while maintaining efficiency and not affecting the driving voltage.

[0007] The present invention is achieved in that:

[0008] In a first aspect, the present invention provides a triarylamine compound containing phenylfluorene, the structural formula of which is shown in the following formula I:

[0009] Formula I, wherein Ar1 represents any one of the groups shown in the following structural formulas:

[0010]

[0011] In a second aspect, the present invention provides a method for preparing the triarylamine compound containing phenylfluorene described in the aforementioned embodiment, and the synthesis is performed according to the following synthesis route:

[0012] Among them, Hal 1 -Hal 2 are halogens respectively.

[0013] In a third aspect, the present invention provides a luminescence auxiliary material for forming a luminescence auxiliary layer, which includes the triarylamine compound containing phenylfluorene described in the aforementioned embodiment.

[0014] In a fourth aspect, the present invention provides an organic electroluminescent device, which comprises a layered structure formed by the triarylamine compound containing phenylfluorene as described in the above embodiment.

[0015] The present invention has the following beneficial effects: the 2-position of dimethylfluorene and the 2-position of 9-methyl-9-phenylfluorene in the compound provided by the embodiment of the present invention are simultaneously connected to triarylamine, and Ar1 is selected from a specific aromatic group. Then, the compound is used as a light-emitting auxiliary layer material, which can further improve the life of the organic electroluminescent device while maintaining efficiency and unaffected driving voltage. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0017] Figure 1 This is the NMR spectrum of the triarylamine compound containing phenylfluorene provided in Example 1 of the present invention. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention will be described clearly and completely below. If the specific conditions are not specified in the embodiments, they are carried out according to conventional conditions or conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be purchased commercially.

[0019] In a first aspect, the present invention provides a triarylamine compound containing phenylfluorene, the structural formula of which is shown in the following formula I:

[0020] Formula I, wherein Ar1 represents any one of the groups shown in the following structural formulas:

[0021]

[0022] In the embodiment of the present invention, the 2-position of dimethylfluorene and the 2-position of 9-methyl-9-phenylfluorene are simultaneously connected to triarylamine, and Ar1 is selected from a specific aromatic group to form a compound. When the compound is used as a light-emitting auxiliary layer material, the life of the organic electroluminescent device can be further improved while maintaining efficiency and unaffected driving voltage.

[0023] Specifically, the sp at position 9 of the fluorene ring 3 The hybridized carbon maintains the spatial configuration of the compound and enhances the recombination of electrons and holes in the light-emitting layer. The -Ar1 part in the aromatic amine side chain is selected from a specific group range, which plays a role in regulating the performance of the compound, while ensuring that the molecular weight of the compound is within a suitable range, further ensuring the film-forming property and thermal stability of the molecule. Triarylamine has a strong hole transport ability, which can reduce the crystallinity and planarity of the molecule and prevent the molecule from moving on the plane. At the same time, the high hole transport rate can reduce the driving voltage of the device and improve the efficiency and life of the organic electroluminescent device.

[0024] Furthermore, the compound is selected from any one of the compounds represented by the following structural formulas: Ar1 is as defined above.

[0025] More specifically, it is selected from any one of the compounds represented by the following structural formulas:

[0026]

[0027]

[0028]

[0029]

[0030]

[0031]

[0032]

[0033] In a second aspect, the present invention provides a method for preparing the triarylamine compound containing phenylfluorene described in the aforementioned embodiment, and the synthesis is performed according to the following synthesis route:

[0034]

[0035] Hal 1 -Hal 2 are respectively halogen, such as chlorine, bromine or iodine.

[0036] The step of forming the intermediate c comprises: mixing reactant a, reactant b, a catalyst, a ligand and an alkaline substance for reaction; the molar ratio of the reactant a, the reactant b, the alkaline substance, the catalyst and the ligand is 1: (1.1-1.5): (20-2.5): (0.01-0.05): (0.02-0.15); the temperature is 130-140° C. and the time is 8-12 hours.

[0037] Specifically, under nitrogen protection, reactant a (1.0 eq) and reactant b (1.1-1.5 eq) are completely dissolved in xylene in a round-bottom flask, and then a base (2.0-2.5 eq), a palladium catalyst (0.01-0.05 eq), and a phosphine ligand (0.02-0.15 eq) are added thereto, and then the resultant is heated to 130-140° C. and stirred for 8-12 hours. Celite is used for hot suction filtration, and after the filtrate is cooled to room temperature, water is then added to the filtrate for washing, and the organic phase is retained after separation, and the aqueous phase is extracted with ethyl acetate; the combined organic layer is then dried with magnesium sulfate, and the remaining substance is purified by column chromatography to obtain intermediate c.

[0038] The step of forming the compound shown in formula I comprises: mixing an intermediate c, a reactant d, a catalyst, a ligand and an alkaline substance for reaction; wherein the molar ratio of the intermediate c, the reactant d, the alkaline substance, the catalyst and the ligand is 1: (1.1-1.5): (20-2.5): (0.01-0.05): (0.02-0.15); the temperature is 130-140° C., and the time is 8-12 hours.

[0039] Specifically, under nitrogen protection, after the intermediate c (1.0 eq) and the reactant d (1.1-1.5 eq) are completely dissolved in xylene in a round-bottom flask, a base (2.0-2.5 eq), a palladium catalyst (0.01-0.05 eq), and a phosphine ligand (0.02-0.15 eq) are added thereto, and then the resultant is heated to 130-140° C. and stirred for 8-12 hours. Celite is used for hot suction filtration, and after the filtrate is cooled to room temperature, water is then added to the filtrate for washing, and the organic phase is retained after separation, and the aqueous phase is extracted with ethyl acetate; the combined organic layer is then dried with magnesium sulfate, and the remaining substance is purified by column chromatography to obtain the compound shown in formula I.

[0040] It should be noted that, in the process of synthesizing the compound shown in Formula I, for undisclosed raw materials, those skilled in the art can synthesize them by using the classic Suzuki coupling reaction and Buchwald-Hartwig coupling reaction, and apply them to the present invention.

[0041] The catalyst may be a palladium catalyst, for example: Pd 2 (dba) 3 (tris(dibenzylideneacetone)dipalladium), Pd(PPh 3 ) 4 (tetrakis(triphenylphosphine)palladium), PdCl 2 (palladium dichloride), PdCl 2 (dppf)(1,1'-bis(diphenylphosphino)ferrocenepalladium dichloride), Pd(OAc) 2 (palladium acetate), Pd(PPh 3 ) 2 Cl 2 (bis(triphenylphosphine)palladium dichloride) or a combination of at least two thereof.

[0042] The ligand may be a phosphine ligand, for example: PPh 3 (triphenylphosphine), P(t-Bu) 3 (tri-tert-butylphosphine), X-phos(2-cyclohexyl-2,4,6-triisopropylbiphenyl), PET 3 (triethylphosphine), PMe 3 (trimethylphosphine), PPh 3 (Triphenylphosphine), KPPh 2 (potassium diphenylphosphonate) or a combination of at least two thereof.

[0043] The alkaline substance can be: AcOK (potassium acetate), K 2 CO 3 , K 3 PO 4 、Na 2 CO 3 , CsF, Cs 2 CO 3 Or t-BuONa (sodium tert-butoxide) or a combination of at least two thereof.

[0044] The triarylamine compounds containing phenylfluorene provided in the embodiments of the present invention can be used as light-emitting auxiliary materials.

[0045] Regarding the compound represented by Formula I, when manufacturing an organic light-emitting element, a vacuum evaporation method or a solution coating method is used to form an organic layer. The so-called solution coating method refers to, but is not limited to, spin coating, dip coating, blade coating, inkjet printing, screen printing, spraying, roller coating, etc.

[0046] In a fourth aspect, the present invention provides an organic electroluminescent device, which comprises a layered structure formed by the triarylamine compound containing phenylfluorene as described in the above embodiment.

[0047] The organic electroluminescent device provided in the embodiment of the present invention is a top-emitting type, a bottom-emitting type or a bidirectional-emitting type according to the materials used.

[0048] The organic electroluminescent devices provided by the present invention include but are not limited to flat panel displays, computer monitors, medical monitors, televisions, billboards, lights for internal or external lighting and / or signals, head-up displays, fully transparent or partially transparent displays, flexible displays, laser printers, telephones, mobile phones, tablets, photo albums, personal digital assistants (PDAs), wearable devices, laptops, digital cameras, camcorders, viewfinders, microdisplays, three-dimensional displays, virtual reality or augmented reality displays, vehicles, video walls including multiple displays tiled together, theater or venue screens, light therapy devices and signs.

[0049] The features and performance of the present invention are further described in detail below in conjunction with the embodiments.

[0050] Example 1

[0051] This embodiment provides a method for preparing a triarylamine compound containing phenylfluorene (hereinafter also referred to as compound 12), comprising:

[0052] The synthesis was carried out according to the following synthesis route:

[0053]

[0054] Among them, CAS: reactant a-12: 1047992-04-0; CAS: reactant b-12: 2808242-64-8. Specifically,

[0055] N 2 Under protection, reactant a-12 (1.0 eq) and reactant b-12 (1.3 eq) were added to the reaction vessel and dissolved in xylene. 2 (dba) 3 (0.02eq), P(t-Bu) 3(0.04eq), t-BuONa (2.2eq); after adding, the reaction temperature was raised to 130°C, and the mixture was stirred for 12h; diatomaceous earth was used for hot filtration, and after the filtrate was cooled to room temperature, distilled water was added to the filtrate for washing, and the organic phase was retained after separation, and the aqueous phase was extracted with ethyl acetate; the combined organic layer was then dried over magnesium sulfate, and purified by column chromatography to obtain intermediate c-12 (yield: 84.3%, test value MS (ESI, m / Z): [M+H] + =539.47).

[0056] N 2 Under protection, intermediate c-12 (1.0 eq) and reactant d-12 (1.2 eq) were added to the reaction vessel and dissolved in xylene, and then Pd 2 (dba) 3 (0.02eq), P(t-Bu) 3 (0.04eq), t-BuONa (2.4eq); after adding, the reaction temperature was raised to 130°C, and the mixture was stirred for 10h; diatomaceous earth was used for hot filtration, and the filtrate was cooled to room temperature, and then distilled water was added to the filtrate for washing, and the organic phase was retained after separation, and the aqueous phase was extracted with ethyl acetate; then the combined organic layer was dried over magnesium sulfate, and purified by column chromatography to obtain compound 12 (yield: 80.5%, test value MS (ESI, m / Z): [M+H] + =767.68).

[0057] Compound 12 was characterized and its H NMR spectrum was as follows Figure 1 As shown. HPLC purity: >99.7%. Elemental analysis: theoretical value: C, 92.27; H, 5.91; N, 1.82; test value: C, 91.95; H, 6.13; N, 1.98.

[0058] Example 2

[0059] This embodiment provides a method for preparing a triarylamine compound containing phenylfluorene (hereinafter also referred to as compound 111), comprising:

[0060] The synthesis was carried out according to the following synthesis route:

[0061]

[0062] Among them, CAS: reactant a-111: 2222970-00-3, specifically,

[0063] N 2 Under protection, reactant a-111 (1.0 eq) and reactant b-111 (1.3 eq) were added to the reaction vessel and dissolved in xylene.2 (dba) 3 (0.02eq), P(t-Bu) 3 (0.05eq), t-BuONa (2.2eq); after adding, the reaction temperature was raised to 130°C, and the mixture was stirred for 12h; diatomaceous earth was used for hot filtration, and after the filtrate was cooled to room temperature, distilled water was added to the filtrate for washing, and the organic phase was retained after separation, and the aqueous phase was extracted with ethyl acetate; the combined organic layer was then dried over magnesium sulfate, and purified by column chromatography to obtain intermediate c-111 (yield: 86.2%, test value MS (ESI, m / Z): [M+H] + =539.55).

[0064] N 2 Under protection, intermediate c-111 (1.0 eq) and reactant d-111 (1.2 eq) were added to the reaction vessel and dissolved in xylene, and Pd 2 (dba) 3 (0.02eq), P(t-Bu) 3 (0.04eq), t-BuONa (2.4eq); after adding, the reaction temperature was raised to 130°C, and the mixture was stirred for 10h; diatomaceous earth was used for hot filtration, and the filtrate was cooled to room temperature, and then distilled water was added to the filtrate for washing, and the organic phase was retained after separation, and the aqueous phase was extracted with ethyl acetate; then the combined organic layer was dried over magnesium sulfate, and purified by column chromatography to obtain compound 111 (yield: 82.9%, test value MS (ESI, m / Z): [M+H] + =691.61).

[0065] Compound 111 was characterized: HPLC purity: >99.8%. Elemental analysis: theoretical value: C, 92.00; H, 5.97; N, 2.02; test value: C, 91.74; H, 6.14; N, 2.21.

[0066] Example 3-Example 34

[0067] The phenylfluorene-containing triarylamine compounds provided in Examples 3-34 were prepared by referring to the preparation method of Example 1 or 2. The molecular formulas and mass spectrum data of the phenylfluorene-containing triarylamine compounds of Examples 3-34 are specifically shown in Table 1.

[0068] Table 1 Molecular formula and mass spectrum of triarylamine compounds containing phenylfluorene in Examples 3-35

[0069] Example Compound Molecular formula MS (ESI, m / Z) Example 3 1 <![CDATA[C 47 H 37 N]]> 615.58 Example 4 2 <![CDATA[C 53 H 41 N]]> 691.62 Example 5 5 <![CDATA[C 51 H 39 N]]> 665.62 Example 6 8 <![CDATA[C 56 H 45 N]]> 731.67 Example 7 15 <![CDATA[C 59 H 45 N]]> 767.52 Example 8 20 <![CDATA[C 59 H 45 N]]> 767.59 Example 9 24 <![CDATA[C 57 H 43 N]]> 741.67 Example 10 27 <![CDATA[C 57 H 43 N]]> 741.63 Embodiment 11 31 <![CDATA[C 57 H 43 N]]> 741.62 Example 12 36 <![CDATA[C 57 H 43 N]]> 741.59 Example 13 40 <![CDATA[C 53 H 41 N]]> 691.66 Embodiment 14 48 <![CDATA[C 59 H 45 N]]> 767.71 Embodiment 15 53 <![CDATA[C 59 H 45 N]]> 767.68 Example 16 58 <![CDATA[C 57 H 43 N]]> 741.65 Embodiment 17 63 <![CDATA[C 57 H 43 N]]> 741.51 Embodiment 18 65 <![CDATA[C 57 H 43 N]]> 741.56 Embodiment 19 71 <![CDATA[C 57 H 43 N]]> 741.68 Embodiment 20 78 <![CDATA[C 51 H 39 N]]> 665.64 Embodiment 21 84 <![CDATA[C 59 H 45 N]]> 767.53 Embodiment 22 91 <![CDATA[C 57 H 43 N]]> 741.62 Embodiment 23 97 <![CDATA[C 59 H 45 N]]> 767.70 Embodiment 24 103 <![CDATA[C 57 H 43 N]]> 741.66 Embodiment 25 108 <![CDATA[C 51 H 39 N]]> 665.53 Embodiment 26 109 <![CDATA[C 53 H 41 N]]> 691.61 Embodiment 27 115 <![CDATA[C 59 H 45 N]]> 767.58 Embodiment 28 118 <![CDATA[C 56 H 45 N]]> 731.63 Embodiment 29 122 <![CDATA[C 59 H 45 N]]> 767.71 Embodiment 30 126 <![CDATA[C 59 H 45 N]]> 767.57 Embodiment 31 130 <![CDATA[C 57 H 43 N]]> 741.50 Embodiment 32 135 <![CDATA[C 57 H 43 N]]> 741.61 Embodiment 33 139 <![CDATA[C 57 H 43 N]]> 741.69 Embodiment 34 142 <![CDATA[C 56 H 45 N]]> 731.52

[0070] It should be noted that other compounds of the present invention can be obtained by referring to the synthesis methods of the above-mentioned embodiments, so they are not listed here one by one. The mass spectrometer model used for mass spectrometry testing in this application is Waters XEVO TQD, low precision, ESI source testing.

[0071] Application Example 1

[0072] This application example provides a method for preparing a red light organic electroluminescent device, comprising:

[0073] a. ITO anode: wash the ITO (indium tin oxide)-Ag-ITO (indium tin oxide) glass substrate with a coating thickness of 14nm / 150nm / 14nm in distilled water twice, ultrasonically wash for 30min, and then repeatedly wash it with distilled water twice, ultrasonically wash for 10min. After washing, transfer it to a spin dryer for drying, and finally bake it in a vacuum oven at 220℃ for 2 hours. After baking, cool it down and use it; use the substrate as the anode, use a vapor deposition machine to carry out the vapor deposition device process, and evaporate other functional layers thereon in sequence.

[0074] b. HIL (hole injection layer): The evaporation rate of the hole injection layer is HT and P-dopant, and the chemical formula thereof is shown below; and the evaporation rate ratio of the HT and P-dopant is 97:3, and the thickness is 10 nm.

[0075] c. HTL (hole transport layer): At a deposition rate of , 120 nm of HT was vacuum evaporated on the hole injection layer as a hole transport layer.

[0076] d. Prime (luminous auxiliary layer): At a deposition rate of , 95 nm of the compound provided in the embodiment of the present invention is vacuum evaporated on the hole transport layer as a light-emitting auxiliary layer material.

[0077] e. EML (luminescent layer): on the luminescent auxiliary layer, The host material (Host) and the dopant material (Dopant) with a thickness of 45 nm are vacuum evaporated at a deposition rate as the light-emitting layer, wherein the chemical formulas of Host and Dopant are shown below, and the deposition rate ratio of Host and Dopant is 95:5.

[0078] f. HB (hole blocking layer): At a deposition rate of , HB with a thickness of 5.0 nm was vacuum-deposited on the light-emitting layer as a hole blocking layer.

[0079] g. ETL (Electron Transport Layer): At a deposition rate of , ET and Liq with a thickness of 30 nm were vacuum evaporated on the hole blocking layer as an electron transport layer; the chemical formulas of ET and Liq are shown below, and the evaporation rate ratio of ET and Liq is 50:50.

[0080] h. EIL (electron injection layer): At a deposition rate of , a 1.0 nm Yb film layer was vacuum-deposited on the electron transport layer to form an electron injection layer.

[0081] i. Cathode: The evaporation rate ratio is 1:9, and 13 nm of magnesium and silver are vacuum evaporated on the electron injection layer, and the evaporation rate ratio is 1:9, to obtain an OLED device.

[0082] j. Light extraction layer: At a evaporation rate of , CPL with a thickness of 70 nm was vacuum-deposited on the cathode as a light extraction layer, where the chemical formula of CPL is shown below.

[0083] k. Package the vapor-deposited substrate: First, use the glue coating equipment to coat the cleaned cover with UV glue, then move the coated cover to the pressing section, place the vapor-deposited substrate on the upper end of the cover, and finally bond the substrate and cover with the bonding equipment, and complete the light curing of the UV glue at the same time.

[0084] The structural formulas of the raw materials required for the above-mentioned layers are as follows:

[0085]

[0086] Application Example 2-32

[0087] The organic electroluminescent devices of Application Examples 2-32 were prepared by referring to the preparation method of the organic electroluminescent device provided in Application Example 1, except that the compound 1 in Application Example 1 was replaced by the corresponding compound (as shown in Table 2) to form a light-emitting auxiliary layer.

[0088] Comparative Examples 1-10

[0089] The organic electroluminescent devices of Comparative Examples 1-10 were prepared by referring to the preparation method of the organic electroluminescent device provided in Application Example 1, except that the compound 1 in Application Example 1 was replaced by comparative compounds 1 to 10 shown in the following structural formulas, respectively.

[0090]

[0091] The driving voltage, luminous efficiency and life of the organic electroluminescent devices obtained from the device application examples 1-32 and the device comparison examples 1-10 were characterized at a brightness of 6000 (nits). The test results are shown in Table 2 below.

[0092] Table 2 Luminous characteristics test results (brightness value is 6000nits)

[0093]

[0094]

[0095] Application Example 33

[0096] This application example provides a method for preparing a green light organic electroluminescent device, comprising:

[0097] a. ITO anode: wash the ITO (indium tin oxide)-Ag-ITO (indium tin oxide) glass substrate with a coating thickness of 14nm / 150nm / 14nm in distilled water twice, ultrasonically wash for 30min, and then repeatedly wash it with distilled water twice, ultrasonically wash for 10min. After washing, transfer it to a spin dryer for drying, and finally bake it in a vacuum oven at 220℃ for 2 hours. After baking, cool it down and use it; use the substrate as the anode, use a vapor deposition machine to carry out the vapor deposition device process, and evaporate other functional layers thereon in sequence.

[0098] b. HIL (hole injection layer): The hole injection layer materials HT1 and P-dopant were vacuum evaporated at a deposition rate of 95:5, and the thickness was 10 nm.

[0099] c. HTL (hole transport layer): At a deposition rate of 100%, 130nm of HT1 was vacuum-deposited on the hole injection layer as a hole transport layer.

[0100] d. Light-emitting auxiliary layer: At a deposition rate of , 40 nm of the compound provided in the embodiment of the present invention is vacuum-deposited on the hole transport layer as a light-emitting auxiliary layer;

[0101] e. EML (light-emitting layer): Then on the above-mentioned light-emitting auxiliary layer, The evaporation rate of the main material (Host-1 and Host-2) and the dopant material (Dopant-G) with a thickness of 40nm are vacuum evaporated as the light-emitting layer, wherein Host-1 and Host-2 are co-evaporated as dual main materials with the dopant material, and the ratio of Host-1 to Host-2 is 50%:50%. The chemical formulas of Host-1, Host-2 and Dopant-G are shown below. The evaporation rate ratio of the main material and Dopant is 90:10.

[0102] f. HBL (hole blocking layer): The evaporation rate was 5.0 nm, and HB-1 was vacuum evaporated to a thickness of 5.0 nm as a hole blocking layer.

[0103] g. ETL (Electron Transport Layer): ET-1 and Liq were vacuum-deposited at a deposition rate of 30 nm as an electron transport layer, where the deposition rate ratio of ET-1 to Liq was 50:50.

[0104] h. EIL (electron injection layer): At a evaporation rate of , a 1.0 nm Yb film layer was evaporated to form an electron injection layer.

[0105] i. Cathode: The evaporation rate ratio of magnesium and silver is 13nm, and the evaporation rate ratio is 1:9 to form a cathode.

[0106] j. Light extraction layer: At a deposition rate of , CPL-1 with a thickness of 60 nm was vacuum-deposited on the cathode as a light extraction layer.

[0107] k. Package the substrate after evaporation. First, use the glue coating equipment to coat the cleaned cover with UV glue, then move the coated cover to the pressing section, place the evaporation-deposited substrate on the upper end of the cover, and finally bond the substrate and cover with the bonding equipment, and complete the light curing of the UV glue.

[0108] The structural formulas of the raw materials required for the above-mentioned layers are as follows:

[0109]

[0110] Application Example 34-Application Example 64

[0111] Organic electroluminescent devices of Application Examples 34-64 are prepared by referring to the preparation method of the organic electroluminescent device Application Example 33, except that Compound 2 in Application Example 33 is replaced by corresponding compounds (refer to the compounds involved in Table 3) to form a light-emitting auxiliary layer.

[0112] Comparative Examples 11-20

[0113] The organic electroluminescent devices of Comparative Examples 11-20 were prepared by referring to the preparation method of the organic electroluminescent device application example 33, except that the compound 2 in application example 33 was replaced by the corresponding comparative compound (refer to the compounds involved in Table 3) to form a luminescent auxiliary layer.

[0114] The driving voltage, luminous efficiency, lifespan, and efficiency roll-off of the organic electroluminescent devices obtained from the device application examples 33-64 and the device comparison examples 11-20 were characterized at a brightness of 15000 (nits). The test results are shown in Table 3 below.

[0115] Table 3 Luminous characteristics test results (brightness value is 15000nits)

[0116]

[0117]

[0118] According to Tables 2 and 3, the phenylfluorene-containing triarylamine compounds provided in the embodiments of the present invention are connected to triarylamine at the 2-position of dimethylfluorene and the 2-position of 9-methyl-9-phenylfluorene at the same time, and when Ar1 is selected from a specific aromatic group as the light-emitting auxiliary layer material, it can be applied to green or red organic electroluminescent devices. Compared with the prior art, the device maintains efficiency, the driving voltage is not affected, and the life is extended by about 100-200 hours, which is further improved.

[0119] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A triarylamine compound containing phenylfluorene, It is characterized in that Its structural formula is shown in the following formula I: Wherein, Ar1 represents any one of the groups shown in the following structural formulas:

2. The triarylamine compound containing phenylfluorene according to claim 1, It is characterized in that It is selected from any one of the compounds represented by the following structural formulas:

3. The triarylamine compound containing phenylfluorene according to claim 1 or 2, It is characterized in that It is selected from any one of the compounds represented by the following structural formulas:

4. A method for preparing the triarylamine compound containing phenylfluorene according to claim 1, It is characterized in that The synthesis was carried out according to the following synthesis route: Among them, Hal 1 -Hal 2 are halogens respectively.

5. The preparation method according to claim 4, It is characterized in that The steps of forming the intermediate c include: mixing reactant a, reactant b, a catalyst, a ligand and an alkaline substance to react; Preferably, the molar ratio of the reactant a, the reactant b, the alkaline substance, the catalyst and the ligand is 1:(1.1-1.5):(20-2.5):(0.01-0.05):(0.02-0.15); The reaction conditions include: temperature of 130-140° C. and time of 8-12 hours.

6. The preparation method according to claim 4, It is characterized in that The steps of forming the compound of formula I include: mixing the intermediate c, the reactant d, the catalyst, the ligand and the alkaline substance for reaction; Preferably, the molar ratio of the intermediate c, the reactant d, the alkaline substance, the catalyst and the ligand is 1:(1.1-1.5):(20-2.5):(0.01-0.05):(0.02-0.15); The reaction conditions include: temperature of 130-140° C. and time of 8-12 hours.

7. A luminescence auxiliary material for forming a luminescence auxiliary layer, It is characterized in that It comprises the triarylamine compound containing phenylfluorene as claimed in claim 1.

8. An organic electroluminescent device, It is characterized in that The invention comprises a layered structure formed by the triarylamine compound containing phenylfluorene as claimed in claim 1.

9. The organic electroluminescent device according to claim 8, It is characterized in that The organic electroluminescent device includes any one of a top-emitting device, a bottom-emitting device and a bi-directional-emitting device.

10. The organic electroluminescent device according to claim 8, It is characterized in that The organic electroluminescent device includes any one of a display, a monitor, a patient monitor, a television, a billboard, a printer, a telephone, a mobile phone, a photo album, a personal digital assistant, a wearable device, a notebook computer, a digital camera, a video camera and a viewfinder.

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