Organic material and organic electroluminescent device using same

Abstract

The invention relates to an organic material and an organic electroluminescent device using the same, and belongs to the technical field of semiconductor materials, the organic material is shown as a general formula (1): # imgabs0 #, and the organic material is applied to a light-emitting auxiliary layer of the organic electroluminescent device. The organic material has excellent anti-electron characteristic, and when the light-emitting auxiliary layer material is used as a light-emitting auxiliary layer for preparing the organic electroluminescent device, the service life prolonging effect is very remarkable.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to an organic material and an organic electroluminescent device using the same. Background Art

[0002] Organic light-emitting diodes (OLEDs) can be used to manufacture new display products as well as new lighting products. They are expected to replace existing liquid crystal displays and fluorescent lighting, and have a wide range of applications. Organic light-emitting diodes are like sandwich structures, including electrode material films and organic functional materials sandwiched between different electrode material films. Various organic functional materials are superimposed on each other according to their uses to form organic light-emitting diodes. As a current device, when voltage is applied to the electrodes at both ends of the organic light-emitting diode, the positive and negative charges in the organic functional material film layer are further compounded in the light-emitting layer through the electric field, generating organic electroluminescence.

[0003] Currently, organic electroluminescent display technology has been applied in smart phones, tablet computers, televisions and other fields. However, compared with the actual product application requirements, the luminous efficiency and service life of organic electroluminescent devices need to be further improved. Research on improving the performance of organic electroluminescent devices includes: reducing the driving voltage of the device, improving the luminous efficiency of the device, and improving the service life of the device. In order to continuously improve the performance of organic electroluminescent devices, it is necessary not only to innovate the structure and manufacturing process of organic electroluminescent devices, but also to continuously study and innovate organic functional materials to create higher performance organic functional materials.

[0004] Blue organic electroluminescent devices have always been the weak point in the development of full-color OLEDs. So far, the efficiency and life of blue light devices have been difficult to be comprehensively improved. Therefore, how to improve the performance of blue light devices is still a crucial issue and challenge facing this field. At present, most of the blue light host materials used in the market are electron-biased hosts. Due to the preferential injection of holes at low current density, the pressure on the hole transmission side is relieved to a certain extent. As the current density increases, the amount of electron injection will increase, causing the recombination area to shift to the hole side, and the pressure on the hole side is increasing. In order to prevent the excitons from being transferred to the hole side, the luminescent auxiliary layer material is required to effectively block the excitons and efficiently transfer the holes to the luminescent layer. At present, most of the luminescent auxiliary layer materials are traditional aromatic amine structures. The electronic tolerance of this type of structure in the prior art still cannot meet the demand. The hole mobility at high current density still needs to be improved, so as to ensure the carrier balance of the luminescent layer and prevent the recombination area from shifting to the hole transmission side due to insufficient holes, resulting in reduced device efficiency and shortened life. Summary of the invention

[0005] In view of the above problems existing in the prior art, the applicant of the present invention provides an organic material and an organic electroluminescent device using the same. When the organic material described in the present invention is used to form a light-emitting auxiliary layer of the organic electroluminescent device, the life of the organic electroluminescent device is significantly improved.

[0006] The technical solution of the present invention to solve the above technical problem is as follows: an organic material, the structure of the organic material is shown in general formula (1):

[0007]

[0008] In the general formula (1), X represents an oxygen atom or a sulfur atom;

[0009] L1 shown here represents a direct bond, a phenylene group, a naphthylene group or a biphenylene group;

[0010] The L2 is selected from the following structures: * indicates the attachment site;

[0011] The R1 represents phenyl, naphthyl, phenyl-substituted naphthyl, dibenzofuranyl or dibenzothienyl;

[0012] The phenyl* site of the general formula (1) is cyclically connected to any adjacent site of S1-S4;

[0013] Any hydrogen atom in the structure represented by the general formula (1) may be replaced by a deuterium atom.

[0014] Furthermore, the structure of the organic material is any one of the general formulas (1-1) to (1-4):

[0015]

[0016] In general formula (1-1) to general formula (1-4), the definitions of L1, L2, R1, and X are the same as those in general formula (1). Further, the structure of the organic material is any one of general formula (1-5) to general formula (1-7):

[0017]

[0018] In general formulae (1-5) to (1-7), the definitions of L1, L2, R1, and X are the same as those in general formula (1). Further, the structure of the organic material is any one of general formulae (2-1) to (2-3):

[0019]

[0020] In general formula (2-1) to general formula (2-3), the definitions of L1 and L2 are the same as those in general formula (1);

[0021] The X represents an oxygen atom;

[0022] The R1 is a phenyl group.

[0023] Furthermore, the structure of the organic material is any one of the general formulas (3-1) to (3-3):

[0024]

[0025] In the general formula (3-1) to the general formula (3-3), the definitions of L1 and X are the same as those defined above.

[0026] Furthermore, the structure of the organic material is as shown in any one of the general formulas (4-1) to (4-9):

[0027]

[0028]

[0029] In the general formula (4-1) to the general formula (4-9), the definitions of L1 and X are the same as those defined above.

[0030] Furthermore, the structure of the organic material is any one of the general formulas (5-1) to (5-9):

[0031]

[0032]

[0033] In the general formulae (5-1) to (5-12), X represents an oxygen atom or a sulfur atom.

[0034] Furthermore, the structure of the organic material is any one of the general formulas (6-1) to (6-4):

[0035] In general formula (6-1) to general formula (6-4), X represents an oxygen atom or a sulfur atom;

[0036] L1 shown here represents a direct bond or a phenylene group.

[0037] Furthermore, the structure of the organic material is any one of the general formulas (7-1) to (7-9):

[0038]

[0039]

[0040] In general formulae (7-1) to (7-9), L1, L2, R1, and X are defined as in general formula (1).

[0041] Further, the R1 is represented by the following structure:

[0042]

[0043] Any of;

[0044] The L1 is represented by a direct bond or the following structure:

[0045] Any one of the following; * indicates the connection site.

[0046] Further, the -L2-R1 is represented by the following structure:

[0047]

[0048]

[0049] Further, the structure of the organic material is any one of the following structures:

[0050]

[0051]

[0052]

[0053]

[0054]

[0055]

[0056]

[0057]

[0058]

[0059]

[0060]

[0061]

[0062] The invention also discloses an organic electroluminescent device, which comprises a substrate, a first electrode, a second electrode and an organic functional layer. The organic functional layer is located between the first electrode and the second electrode, and contains the organic material of the invention.

[0063] Furthermore, the organic functional layer includes a hole transport region, the hole transport region includes a hole injection layer, a hole transport layer and a light-emitting auxiliary layer, and the light-emitting auxiliary layer contains the organic material described in the present invention.

[0064] The beneficial technical effects of the present invention are:

[0065] (1) In the organic material structure described in the present invention, naphthofuran or naphthothiophene is a branch chain of an aromatic amine compound, and is connected to the nitrogen atom in the aromatic amine group with at least one phenyl group in the middle as a bridging group. One branch chain is a naphthyl group with phenyl groups connected at both ends, and the connection is in the para position. The specific group connection methods listed in the present invention are combined to make the compounds of the present invention have more excellent anti-electron ability. When applied to devices, the interface between the light-emitting auxiliary layer and the light-emitting layer is more stable, thereby improving the life of the device.

[0066] (2) The structural characteristics of the organic material described in the present invention are conducive to improving the glass transition temperature of the molecules and at the same time helping to reduce the evaporation temperature of the molecules. That is to say, even if the molecular weight of the structure is relatively high, it can ensure a lower evaporation temperature. This excellent performance is not only conducive to the thermal evaporation of the material, but also controls the thermal decomposition rate of the material, thereby improving the stability of the material in device applications.

[0067] The organic functional materials constituting the OLED device include not only hole injection conductive materials but also electron injection conductive materials and light-emitting layer materials. Good device application effects require good carrier balance as a guarantee. Therefore, in order to obtain the best device application effects, the aromatic amine compounds matching the characteristic structure of the present invention also require specific electronic materials to be matched. Based on the in-depth research of the inventors, the electronic materials are preferably materials containing azabenzene structural characteristics, such as triazine materials, pyridine materials, pyrazine materials, etc. or compounds containing these characteristic groups. BRIEF DESCRIPTION OF THE DRAWINGS

[0068] Figure 1 is a schematic structural diagram of the organic electroluminescent device described in the embodiment;

[0069] In the figure, 1, glass substrate layer; 2, anode layer; 3, hole injection layer; 4, hole transport layer; 5, luminescence auxiliary layer; 6, luminescent layer; 7, hole blocking layer; 8, electron transport layer; 9, electron injection layer; 10, cathode layer; 11, CPL layer;

[0070] Figure 2 NMR spectrum of compound 10;

[0071] Figure 3 NMR spectrum of compound 15. DETAILED DESCRIPTION

[0072] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0073] In the present invention, when a layer or element is referred to as being "on" another layer or substrate, the layer or element may be directly on the other layer or substrate, or intervening layers may also be present. In addition, it will be understood that when a layer is referred to as being "between" two layers, the layer may be the only layer between the two layers, or one or more intervening layers may also be present.

[0074] In the present invention, when describing electrodes and organic electroluminescent devices, as well as other structures, the words "upper", "lower", "top" and "bottom" used to indicate orientation only indicate the orientation in a certain state, and do not mean that the related structure can only exist in the orientation described; on the contrary, if the structure can change its position, such as inverted, the orientation of the structure will be changed accordingly. Specifically, in the present invention, the "bottom" or "lower" side of the electrode refers to the side of the electrode close to the substrate during the preparation process, and the opposite side away from the substrate is the "top" or "upper" side.

[0075] In this specification, the term "substituted" means that one or more hydrogen atoms on a designated atom or group are replaced by a designated group, provided that the normal valency of the designated atom is not exceeded under the existing circumstances.

[0076] In this specification, the hole characteristic refers to a characteristic that can donate electrons when an electric field is applied and holes formed in the anode are easily injected into the light-emitting layer and transported in the light-emitting layer due to the conductive characteristic according to the highest occupied molecular orbital (HOMO) level.

[0077] In this specification, the electronic characteristics refer to the characteristics that electrons formed in the cathode can be easily injected into the light-emitting layer and transported in the light-emitting layer due to the conductive characteristics according to the lowest unoccupied molecular orbital (LUMO) level when an electric field is applied.

[0078] The organic electroluminescent device of the present invention may be a bottom-emitting organic electroluminescent device, a top-emitting organic electroluminescent device, or a stacked organic electroluminescent device, without any particular limitation.

[0079] The organic electroluminescent device of the present invention comprises a substrate, a first electrode, a multi-layer organic thin film layer and a second electrode. The multi-layer organic thin film layer comprises a hole transport region, a light emitting region and an electron transport region, the hole transport region comprises a hole injection layer, a hole transport layer and a light emitting auxiliary layer, the electron transport region comprises a hole blocking layer, an electron transport layer and an electron injection layer, and a CPL layer may be arranged on the second electrode.

[0080] The first electrode may be an anode or a cathode, and the second electrode may be a cathode or an anode.

[0081] In the organic electroluminescent device of the present invention, any substrate commonly used in organic electroluminescent devices can be used. Examples thereof are transparent substrates, such as glass or transparent plastic substrates; opaque substrates, such as silicon substrates; flexible polyimide (PI) film substrates. Different substrates have different mechanical strengths, thermal stability, transparency, surface smoothness, and waterproofness. Depending on the properties of the substrate, its use direction is different. In the present invention, a transparent glass substrate is preferably used. The thickness of the substrate is not particularly limited.

[0082] anode:

[0083] In the present invention, an anode may be formed on a substrate. The anode and the cathode are opposite to each other. The anode may be made of a conductor having a higher work function to facilitate hole injection, and may be, for example, a metal such as nickel, platinum, copper, zinc, silver, or an alloy thereof; a metal oxide such as zinc oxide, indium oxide, indium tin oxide (ITO), and indium zinc oxide (IZO); a combination of a metal and a metal oxide such as ZnO and Al or ITO and Ag; a conductive polymer such as poly(3-methylthiophene), poly(3,4-(ethylene-1,2-dioxy)thiophene) and polyaniline, but not limited thereto. The thickness of the anode depends on the material used, and is typically 50-500 nm, preferably 70-300 nm, and more preferably 100-200 nm. In the present invention, metal Ag is preferably used.

[0084] cathode:

[0085] The cathode can be made of a conductor with a lower work function to facilitate electron injection, such as a metal or its alloy, such as magnesium, calcium, sodium, potassium, titanium, indium, aluminum, silver, tin, and combinations thereof; a multilayer structure material, such as LiF / Al, Li2O / Al, and BaF2 / Ca, but not limited thereto. The thickness of the cathode depends on the material used, and is generally 10-50 nm, preferably 15-20 nm.

[0086] Emitting area:

[0087] In the present invention, the light-emitting region can be arranged between the anode and the cathode, and can include at least one host material and at least one guest material. As the host material and the guest material of the light-emitting region of the organic electroluminescent device of the present invention, the light-emitting layer materials for organic electroluminescent devices known in the prior art can be used.

[0088] In a preferred embodiment of the present invention, the light emitting region comprises one or two host material compounds.

[0089] In a preferred embodiment of the present invention, the host material of the light-emitting region used is selected from one or more of the following compounds BH1-BH6:

[0090]

[0091] In the present invention, the light-emitting region may contain a phosphorescent or fluorescent guest material to improve the fluorescent or phosphorescent properties of the organic electroluminescent device. Specific examples of phosphorescent guest materials include metal complexes of iridium, platinum, etc. For fluorescent guest materials, those commonly used in the art can be used. In a preferred embodiment of the present invention, the guest material of the light-emitting film layer used is selected from one of the following compounds BD1 to BD7:

[0092]

[0093] In the light emitting region of the present invention, the ratio of the host material to the guest material used is 99:1-70:30, preferably 99:1-85:15, and more preferably 97:3-87:13, based on mass.

[0094] The thickness of the light emitting region may be 10-50 nm, preferably 15-30 nm, but the thickness is not limited to this range.

[0095] Hole transport region:

[0096] In the organic electroluminescent device of the present invention, the hole transport region is arranged between the anode and the light emitting region, and includes a hole injection layer, a hole transport layer and a light emitting auxiliary layer.

[0097] Hole injection layer:

[0098] The hole injection material used in the hole injection layer (also called the anode interface buffer layer) is a material that can fully accept holes from the anode at a low voltage, and the highest occupied molecular orbital (HOMO) of the hole injection material is preferably a value between the work function of the anode material and the HOMO of the adjacent organic material layer. In a preferred embodiment of the present invention, the hole injection layer is a mixed film layer of a main organic material and a P-type doping material. In order to smoothly inject holes from the anode into the organic film layer, the HOMO energy level of the main organic material must have certain characteristics with the P-type doping material, so that it is expected to realize the occurrence of charge transfer states between the main material and the doping material, and realize the ohmic contact between the hole injection layer and the anode, thereby realizing efficient injection of holes from the electrode to the hole injection layer. This feature is summarized as: the difference between the HOMO energy level of the main material and the LUMO energy level of the P-type doping material is ≤0.4eV. Therefore, for hole-type main materials with different HOMO energy levels, different P-type doping materials need to be selected to match them in order to achieve ohmic contact at the interface and improve the hole injection effect.

[0099] Preferably, the host organic material is an aromatic amine-based organic material, but is not limited thereto.

[0100] Preferably, the P-type doping material is selected from the compounds with charge conductivity disclosed in the prior art, and the P-type dopant can be selected from the compounds disclosed in the following patent documents: WO2011073149A, EP1968131A1, EP2276085A1, EP2213662A1, EP1722602A1, EP2045848A1, DE102007031220A 1. US20100181555A1, US20100102709A1, WO2009003455A1, WO2010094378A1, WO2011120709A1, US20100096600A1, DE102012209523A1, CN101728485A and WO2012095143A1, but are not limited thereto.

[0101] In a preferred embodiment of the present invention, the P-type doping material used is selected from any one of the following compounds HI1 to HI8:

[0102]

[0103] In one embodiment of the present invention, the ratio of the host organic material to the P-type doping material used is 99:1-95:5, preferably 99:1-97:3, based on mass.

[0104] In a preferred embodiment of the present invention, the hole injection layer is a mixed film layer of an aromatic amine compound and a P-type doping material.

[0105] The thickness of the hole injection layer of the present invention may be 5-20 nm, preferably 8-15 nm, but the thickness is not limited to this range.

[0106] Hole transport layer:

[0107] In the organic electroluminescent device of the present invention, a hole transport layer may be disposed on the hole injection layer. The hole transport material is a suitable material with high hole mobility, which can accept holes from the anode or the hole injection layer and transfer the holes to the light-emitting layer. Specific examples thereof include: aromatic amine organic materials, conductive polymers, block copolymers having both conjugated and non-conjugated parts, etc., but are not limited thereto. In a preferred embodiment, the hole transport layer comprises the same aromatic amine organic compound as the hole injection layer.

[0108] Preferably, the hole transport layer material of the present invention may be selected from the following compounds disclosed in the prior art:

[0109]

[0110]

[0111] The thickness of the hole transport layer of the present invention may be 80, 100 or 200 nm, preferably 100-150 nm, but the thickness is not limited to this range.

[0112] Luminous auxiliary layer:

[0113] In the organic electroluminescent device of the present invention, the luminescence auxiliary layer may be arranged between the hole transport layer and the luminescent layer, and in particular contact the luminescent layer. The luminescence auxiliary layer is arranged to contact the luminescent layer, and therefore, the hole transfer at the interface between the luminescent layer and the hole transport layer can be accurately controlled. In one embodiment of the present invention, the luminescence auxiliary layer material is selected from the organic material described in the general formula (1). The thickness of the luminescence auxiliary layer may be 5-20nm, preferably 8-15nm, but the thickness is not limited to this range.

[0114] Electron transport region:

[0115] In the organic electroluminescent device of the present invention, the electron transport region is disposed between the light emitting region and the cathode, and includes a hole blocking layer, an electron transport layer and an electron injection layer, but is not limited thereto.

[0116] Electron injection layer:

[0117] The electron injection layer may be disposed between the electron transport layer and the cathode. The electron injection layer material is generally preferably a material having a low work function so that electrons are easily injected into the organic functional material layer. Preferably, the electron injection layer material is an N-type metal material. As the electron injection layer material of the organic electroluminescent device of the present invention, the electron injection layer material for organic electroluminescent devices known in the prior art can be used, for example, lithium; lithium salts such as 8-hydroxyquinoline lithium, lithium fluoride, lithium carbonate or lithium azide; or cesium salts, cesium fluoride, cesium carbonate or cesium azide.

[0118] The thickness of the electron injection layer of the present invention may be 0.1-5 nm, preferably 0.5-3 nm, and more preferably 0.8-1.5 nm, but the thickness is not limited to this range.

[0119] Electron transport layer:

[0120] The electron transport layer may be disposed on the light-emitting film layer or (if present) the hole blocking layer. The electron transport layer material is a material that easily receives electrons from the cathode and transfers the received electrons to the light-emitting layer. A material having a high electron mobility is preferred. As the electron transport layer of the organic electroluminescent device of the present invention, the electron transport layer material for organic electroluminescent devices known in the prior art can be used.

[0121] As the electron transport layer of the organic electroluminescent device of the present invention, the following compounds disclosed in the prior art can be used as electron transport layer materials of the organic electroluminescent device:

[0122]

[0123]

[0124] The electron transport layer further includes other compounds conventionally used in electron transport layers, for example, Alq3, LiQ, preferably LiQ.

[0125] The thickness of the electron transport layer of the present invention may be 10-80 nm, preferably 20-60 nm, and more preferably 25-45 nm, but the thickness is not limited to this range.

[0126] Hole blocking layer:

[0127] The hole blocking layer may be disposed between the light-emitting layer and the electron transport layer. The hole blocking layer is used to block the holes injected from the anode from passing through the light-emitting layer and entering the electron transport layer. As the hole blocking layer of the organic electroluminescent device of the present invention, the hole blocking layer materials for organic electroluminescent devices disclosed in the following prior art may be used:

[0128]

[0129] Overlay:

[0130] In order to improve the light extraction efficiency of the organic electroluminescent device, a light extraction layer (ie, CPL layer, also called covering layer) may be added on the cathode of the device. The compounds disclosed in the prior art may be used as the CPL layer material.

[0131]

[0132] The thickness of the CPL cover layer is typically 5-300 nm, preferably 20-100 nm, and more preferably 40-80 nm.

[0133] The organic electroluminescent device of the present invention may further include an encapsulation structure. The encapsulation structure may be a protective structure that prevents foreign substances such as moisture and oxygen from entering the organic layer of the organic electroluminescent device. The encapsulation structure may be, for example, a can, such as a glass can or a metal can; or a thin film covering the entire surface of the organic layer.

[0134] The method for preparing an organic electroluminescent device of the present invention comprises laminating an anode, a hole injection layer, a hole transport layer, a light-emitting layer auxiliary layer, an organic film layer, an electron transport layer, an electron injection layer and a cathode successively on a substrate, and optionally a covering layer. In this regard, vacuum deposition, vacuum evaporation, spin coating, casting, LB method, inkjet printing, laser printing or LITI methods can be used, but are not limited thereto. In the present invention, it is preferred to use a vacuum evaporation method to form the various layers. Those skilled in the art can conventionally select various process conditions in the vacuum evaporation method according to actual needs.

[0135] In addition, it should be noted that the materials used to form each layer described in the present invention can be formed into a film alone and used as a single layer, or can be mixed with other materials to form a film and used as a single layer. It can also be a stacked structure between layers formed into films alone, a stacked structure between layers formed into films after mixing, or a stacked structure of layers formed into films alone and layers formed into films after mixing.

[0136] Synthesis Example

[0137] Example 1: Synthesis of Compound 15

[0138]

[0139] In a three-necked flask, under nitrogen protection, add 2.96g (0.009mol) of raw material A-1, 4.92g (0.011mol) of raw material B-2, and 150ml of toluene, stir and mix, then add 0.055g (6×10 -5 mol)Pd2(dba)3,0.01g(5×10 -5mol) tri-tert-butyl phosphine, 2.7 g (0.028 mol) sodium tert-butoxide, heated to 115°C, refluxed for 28 hours, sampling point plate, showing no raw material A-1 remaining, the reaction was complete; naturally cooled to room temperature, filtered, the filtrate was rotary evaporated until there was no fraction, passed through a neutral silica gel column, to obtain compound 15.

[0140] The compound was prepared by the same method as in Example 1, except that different raw materials were used. The raw materials used are shown in Table 1 below:

[0141] Table 1

[0142]

[0143]

[0144]

[0145]

[0146] Example 2: Synthesis of Intermediate A-1

[0147]

[0148] Under nitrogen atmosphere, 0.06mol (15.1g) of raw material D-1 was added to a three-necked flask, and a mixed solvent (300ml toluene, 90ml H2O) was added to dissolve it, and nitrogen was stirred for 1 hour, and then 0.05mol (7.81g) of raw material C-1, 0.1mol (13.82g) K2CO3, and 0.002mol (2.31g) Pd(PPh3)4 were slowly added, heated to 95°C, reacted for 8.5 hours, and the reaction was observed by thin layer chromatography (TLC) until the reaction was complete. Natural cooling, filtration, rotary evaporation of the filtrate, and silica gel column were used to obtain intermediate A-1. The synthesis of other intermediates A is similar to the synthesis method of A-1, and its specific raw materials are shown in Table 2 below:

[0149] Table 2

[0150]

[0151]

[0152] Example 2: Synthesis of Intermediate B-3

[0153]

[0154] In a three-necked flask, under nitrogen protection, 3.96 g (0.015 mol) of raw material F-3, 5.9 g (0.020 mol) of raw material E-3, and 150 ml of toluene were added and stirred, and then 0.037 g (4×10-5 mol)Pd2(dba)3, 0.009g(4.5×10 -5 mol) tri-tert-butyl phosphine, 3.08g (0.032mol) sodium tert-butoxide, heated to 110°C, refluxed for 35 hours, sampling point plate, showing no raw material F-3 remaining, the reaction was complete; naturally cooled to room temperature, filtered, the filtrate was rotary evaporated until there was no fraction, passed through a neutral silica gel column, and intermediate B-3 was obtained.

[0155] The intermediate B was prepared by the same method as in Example 2, except that different raw materials were replaced. The raw materials used are shown in Table 3 below:

[0156] Table 3

[0157]

[0158]

[0159]

[0160] The following describes in detail the application effect of the synthesized mechanical functional material of the present invention in the device through device examples 1-23 and device comparison examples 1-15. The device manufacturing process of device examples 1-23 of the present invention is exactly the same as that of device comparison examples 1-15, and the same substrate material and electrode material are used, and the film thickness of the electrode material is also the same. The difference is that the light-emitting auxiliary layer material in the device is replaced.

[0161] Device Comparison Example 1

[0162] The specific preparation process is as follows:

[0163] like Figure 1As shown, the glass substrate layer 1 is an anode layer 2 (Ag (100nm)) formed by vacuum evaporation. On the anode layer 2, a vacuum evaporation device is used to evaporate HT1 and HI1 with a film thickness of 10nm as a hole injection layer 3, and the mass ratio of HT1 and HI1 is 97:3. Then, HT1 with a thickness of 120nm is evaporated as a hole transport layer 4. Then, EB-1 with a thickness of 10nm is evaporated as a light-emitting auxiliary layer 5. After the evaporation of the above-mentioned light-emitting auxiliary layer 5 materials is completed, the light-emitting layer 6 of the organic electroluminescent device is prepared, and its structure includes BH1 used as the main material of the OLED light-emitting layer 6, BD1 as the doping material, the doping ratio of the doping material is 3% by weight, and the thickness of the light-emitting layer 6 is 20nm. After the above-mentioned light-emitting layer 6, HB1 is continuously evaporated with a film thickness of 5nm as a hole blocking layer 7. On the above-mentioned hole blocking layer 7, ET-1 and LiQ are continuously evaporated, and the mass ratio of ET-1 and LiQ is 1:1. The vacuum-deposited film thickness of the material is 30 nm, and this layer is the electron transport layer 8. On the electron transport layer 8, a LiF layer with a film thickness of 1 nm is made by a vacuum evaporation device, and this layer is the electron injection layer 9. On the electron injection layer 9, a Mg:Ag electrode layer with a film thickness of 16 nm is made by a vacuum evaporation device, and the mass ratio of Mg to Ag is 1:9, and this layer is used as the cathode layer 10. On the cathode layer 10, 65 nm of CP-1 is vacuum-deposited as the CPL layer 11.

[0164] Device Comparison Example 2-15: The preparation method of Device Comparison Example 2-15 is the same as that of Device Comparison Example 1, except that the organic materials of the light-emitting auxiliary layer use organic compounds EB2, EB3, EB4, EB5, EB6, EB7, EB8, EB9, EB10, EB11, EB12, EB13, EB14, and EB15, respectively.

[0165] Device Example 1-23: The preparation method of Device Example 1-23 is the same as that of Device Comparative Example 1, except that the organic material of the light-emitting auxiliary layer uses the aromatic amine compounds described in the present invention. The specific structural compositions of Device Example 1-23 and Device Comparative Example 1-15 are shown in Table 3.

[0166] The molecular structures of the materials involved in the preparation process are shown below:

[0167]

[0168] After the organic electroluminescent device is completed as described above, the anode and cathode are connected using a known driving circuit, and the current efficiency, luminescence spectrum and life of the device are measured.

[0169] Table 3

[0170]

[0171]

[0172]

[0173]

[0174] In the table above, taking device embodiment 1 as an example, "HI1:HT1=3:97 10nm" in the second column means that the materials used for the hole injection layer are compound HT1 and P-type doping material HI1, 3:97 means that the weight ratio of P-type doping material HI1 to compound HT1 is 3:97, and 10nm means the thickness of the layer; "10 10nm" in the fourth column means that the material used is compound 10, and the thickness of the layer is 10nm. The meanings in other tables can be deduced by analogy.

[0175] After the organic electroluminescent device is prepared, the cathode and anode are connected by a known driving circuit, and various properties of the device are measured. The device performance results of device examples 1-23 and device comparative examples 1-15 are shown in Table 4.

[0176] Table 4

[0177]

[0178]

[0179]

[0180] Note: The current efficiency and color coordinates were tested using an IVL (current-voltage-luminance) test system (Suzhou Foster Scientific Instrument Co., Ltd.), and the current density during the test was 10 mA / cm 2 ; The life test system is the EAS-62C OLED device life tester from Japan System Technology Co., Ltd.; LT95 refers to the current density of 30mA / cm 2 Under normal circumstances, the time taken for the device brightness to decay to 95% of its original brightness.

[0181] It can be seen from the device data results that, compared with device comparison examples 1-15, the lifespan of the organic light-emitting devices using the aromatic amine compounds of the present invention is greatly improved compared with the organic electroluminescent devices using known materials in the prior art.

[0182] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are exhaustively listed. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0183] For those skilled in the art, several modifications and improvements may be made without departing from the concept of the present invention, all of which belong to the protection scope of the present invention. The protection scope of the present invention shall be based on the attached claims.

Claims

1. An organic material, characterized in that The structure of the organic material is shown in general formula (1): In the general formula (1), X represents an oxygen atom or a sulfur atom; L1 shown here represents a direct bond, a phenylene group, a naphthylene group or a biphenylene group; The L2 is selected from the following structures: * indicates the connection site; The R1 represents phenyl, naphthyl, phenyl-substituted naphthyl, dibenzofuranyl or dibenzothienyl; The phenyl* site of the general formula (1) is cyclically connected to any adjacent site of S1-S4; Any hydrogen atom in the structure represented by the general formula (1) may be replaced by a deuterium atom.

2. The organic material according to claim 1, characterized in that The structure of the organic material is any one of the general formulas (2-1) to (2-3): In general formula (2-1) to general formula (2-3), the definitions of L1 and L2 are the same as those in claim 1; The X represents an oxygen atom; The R1 is a phenyl group.

3. An organic material according to claim 1, characterized in that: The structure of the organic material is any one of the general formulas (3-1) to (3-3): In general formula (3-1) to general formula (3-3), the definitions of L1 and X are the same as those in claim 1.

4. An organic material according to claim 1, characterized in that: The structure of the organic material is shown in any one of the general formulas (4-1) to (4-9): In general formula (4-1) to general formula (4-9), the definitions of L1 and X are the same as those in claim 1.

5. An organic material according to claim 1, characterized in that: The structure of the organic material is any one of the general formulas (5-1) to (5-9): In the general formulae (5-1) to (5-12), X represents an oxygen atom or a sulfur atom.

6. An organic material according to claim 1, characterized in that: The structure of the organic material is any one of the general formulas (6-1) to (6-4): In general formula (6-1) to general formula (6-4), X represents an oxygen atom or a sulfur atom; L1 shown here represents a direct bond or a phenylene group.

7. An organic material according to claim 1, characterized in that: The -L2-R1 is represented by the following structure: Any one of .

8. An organic material according to claim 1, characterized in that: The structure of the organic material is any one of the following structures:

9. An organic electroluminescent device, comprising a substrate, a first electrode, a second electrode and an organic functional layer, wherein the organic functional layer is located between the first electrode and the second electrode, characterized in that: The organic functional layer contains the organic material according to any one of claims 1 to 8.

10. The organic electroluminescent device according to claim 9, characterized in that: The organic functional layer comprises a hole transport region, the hole transport region comprises a hole injection layer, a hole transport layer and a light-emitting auxiliary layer, and the light-emitting auxiliary layer comprises the organic material according to any one of claims 1 to 8.

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