An optical extraction layer and top-emitting organic electroluminescent device comprising the same

Abstract

This invention relates to a light extraction layer and a top-emitting organic electroluminescent device containing the same. The light extraction layer of this invention comprises, sequentially along the light emission direction, a first capping layer, a second capping layer, and a third capping layer. The first capping layer contains a phosphazene compound or a siloxane compound, and the second capping layer contains a fluorinated organic compound. The refractive index of the organic material in the first capping layer is less than that in the second capping layer, and the refractive index of the organic material in the second capping layer is less than that in the third capping layer. When applied to a top-emitting organic electroluminescent device, the light extraction layer of this invention can effectively improve the light extraction efficiency of the device.

Description

Technical Field

[0001] This invention relates to the field of semiconductor technology, and more particularly to a light extraction layer and a top-emitting organic electroluminescent device comprising the same. Background Technology

[0002] Organic light-emitting diodes (OLEDs), also known as organic electroluminescent devices, are a technology that uses organic materials to emit light through carrier injection and recombination under the influence of an electric field. They can convert electrical energy into light energy through organic light-emitting materials. OLEDs are essentially thin-film stacked devices. Depending on the light transmission path, these devices can be divided into bottom-emitting devices and top-emitting devices. In bottom-emitting devices, light propagates from the anode through the substrate to the outside of the device, while in top-emitting devices, light propagates through the cathode to the outside of the device. Due to the different light emission methods, their applications differ significantly. Top-emitting devices emit light from the cathode side without passing through the substrate, successfully avoiding the reduced aperture ratio problem that occurs in bottom-emitting devices, resulting in more delicate and clear images, as well as higher color vibrancy.

[0003] In top-emitting organic electroluminescent devices, when light emitted from the light-emitting layer is incident on other films at an angle greater than a certain value, total internal reflection will occur at the interface between the light-emitting layer and other films. Therefore, only a portion of the emitted light can be utilized. In recent years, to improve light extraction efficiency, it has been proposed to place a high-refractive-index organic compound as a CPL (coating layer) on the outside of a semi-transparent electrode with a low refractive index as the light-emitting element.

[0004] However, it is very difficult to further increase the refractive index of the organic compound in the capping layer. Therefore, in order to further improve the luminous efficiency of organic light-emitting elements without adding too much material, a double capping layer structure consisting of a low refractive index capping layer and a high refractive index capping layer was explored.

[0005] Due to the refractive index difference between the high-refractive-index CPL (capsule layer) and the low-refractive-index CPL on the dual capping layer, a portion of the light emitted from the light-emitting layer passes through the capping layer, while the remaining portion is reflected by the capping layer. Light is particularly reflected at the interfaces between the high-refractive-index CPL and the low-refractive-index CPL, and at the interface between the high-refractive-index CPL and the encapsulation structure. The light reflected by the capping layer is reflected again at the electrodes and is amplified during this repeated reflection. Therefore, repeated reflections can occur at the interfaces between the high-refractive-index CPL and the low-refractive-index CPL, and between the high-refractive-index CPL and the encapsulation structure, thereby recovering light lost due to reflection on the surface facing away from the OLED.

[0006] Based on the double-layer light extraction layer, CN117396036A discloses a three-layer light extraction layer structure, in which a first layer, a second layer and a third layer are arranged sequentially along the light emission direction. The refractive index of the organic material in the second layer is higher than that of the organic material in the first layer. The organic materials of the first layer and the third layer are the same fluorine-containing organic material. Compared with the double-layer structure, this three-layer light extraction layer structure improves the luminous efficiency of the organic light-emitting device to a certain extent, but some light is still lost due to diffuse scattering.

[0007] To continuously improve the efficiency of OLED devices, it is necessary to continuously innovate the structure and manufacturing process of OLED devices. Therefore, finding a suitable light extraction layer structure for OLED devices to solve the above problems is a long-term need in this field. Summary of the Invention

[0008] To address the aforementioned problems in the existing technology, this application provides a light extraction layer. By adding a lower refractive index layer containing a phosphazene compound or a siloxane compound between the light-transmitting electrode and the lower refractive index layer, the problem of low device luminous efficiency can be effectively improved.

[0009] The present invention provides the following technical solution: a light extraction layer, comprising, in sequence along the light extraction direction:

[0010] First covering layer;

[0011] A second cover layer is placed on top of the first cover layer;

[0012] A third cover layer, which is located on top of the second cover layer;

[0013] The first capping layer contains a phosphazene compound or a siloxane compound;

[0014] The second coating layer contains a fluorinated organic compound;

[0015] The refractive index of the material in the first capping layer is less than that of the material in the second capping layer, and the refractive index of the material in the second capping layer is less than that of the material in the third capping layer.

[0016] Furthermore, the first covering layer is composed of a phosphazene compound or a siloxane compound;

[0017] Furthermore, the second coating layer is composed of fluorinated organic compounds;

[0018] Furthermore, the material in the third covering layer is an organic compound;

[0019] Furthermore, the refractive index of the material in the third capping layer is n3@460nm≥1.80, preferably n3@460nm≥1.90, preferably n3@460nm≥2.00, preferably n3@460nm≥2.10, preferably n3@460nm≥2.15, and preferably n3@460nm≥2.20.

[0020] The refractive index of the material in the second capping layer is 1.40≤n2@460nm≤1.70, preferably 1.40≤n2@460nm≤1.65, preferably 1.40≤n2@460nm≤1.60, preferably 1.40≤n2@460nm≤1.55, preferably 1.40≤n2@460nm≤1.50, and preferably 1.40≤n2@460nm≤1.45.

[0021] The refractive index of the material in the first capping layer is 1.10≤n1@460nm≤1.40, preferably 1.20≤n1@460nm≤1.4, preferably 1.25≤n1@460nm≤1.40, and preferably 1.30≤n1@460nm≤1.40.

[0022] Furthermore, the difference in refractive index between the material in the second capping layer and the material in the first capping layer, Δn@460nm, is ≥0.10, preferably Δn@460nm is 0.10-0.50, and more preferably Δn@460nm is 0.15-0.30.

[0023] Furthermore, the difference in refractive index between the material in the second capping layer and the material in the third capping layer, Δn@460nm, is ≥0.50, preferably Δn@460nm is 0.50-1.20, preferably Δn@460nm is 0.50-1.00, preferably Δn@460nm is 0.55-0.95, preferably Δn@460nm is 0.60-0.90, and preferably Δn@460nm is 0.65-0.86.

[0024] Furthermore, the phosphazene compound contains fluorinated branches, and the siloxane compound contains fluorinated branches;

[0025] Preferably, the fluorinated branch includes at least one of the following: substituted fluoroalkyl, unsubstituted fluoroalkyl, substituted fluoroalkoxy, unsubstituted fluoroalkoxy, substituted fluoroalkylsilyloxy, unsubstituted fluoroalkylsilyloxy, substituted fluorocycloalkyl, unsubstituted fluorocycloalkyl, substituted fluoroaryl, and unsubstituted fluoroaryl.

[0026] Preferably, the substituted or unsubstituted fluoroalkyl group is selected from at least one of the following fluorocarbon units: CF, CF2, CF3 and CF2H units, more preferably fluorocarbon units: CF2, CF3 and CF2H units, and more preferably fluorocarbon units: CF3 and CF2H units.

[0027] Furthermore, the core skeleton of the phosphazene compound is a cyclophosphazene structure, and the core skeleton of the siloxane compound is a silsesquioxane structure;

[0028] Preferably, the phosphazene compound has a structure comprising a cyclophosphazene core framework and branched chains, wherein the branched chain comprises a main chain and a fluorine-containing portion attached to the main chain, and more preferably, the main chain is a carbon main chain.

[0029] Preferably, the number of branches connected to the core skeleton of the phosphazene compound is 2-8, more preferably 4-7.

[0030] Preferably, the core skeleton and the branched connecting portion comprise at least one of the following: direct bond, oxygen, ether, substituted alkylene, unsubstituted alkylene, substituted fluoroalkylene, unsubstituted fluoroalkylene, substituted cycloalkylene, unsubstituted cycloalkylene, substituted heteroaryl or unsubstituted heteroaryl.

[0031] Preferably, the fluorinated portion on the main chain is selected from at least one of the following fluorocarbon units: CF, CF2, CF3 and CF2H units, more preferably fluorocarbon units: CF2, CF3 and CF2H units, and even more preferably fluorocarbon units: CF3 and CF2H units.

[0032] Preferably, the siloxane compound comprises a silicon-oxygen cyclic core framework and at least one branch connected to the silicon-oxygen cyclic framework, the branch comprising a fluorine-containing portion.

[0033] Preferably, the branched portion includes a main chain and a fluorine-containing portion attached to the main chain; more preferably, the main chain is a carbon main chain.

[0034] Preferably, the fluorinated portion on the main chain is selected from at least one of the following fluorocarbon units: CF, CF2, CF3 and CF2H units, more preferably fluorocarbon units: CF2, CF3 and CF2H units, and even more preferably fluorocarbon units: CF3 and CF2H units.

[0035] Preferably, the core skeleton and the branched connecting portion comprise at least one of the following: direct bond, oxygen, ether, substituted alkylene, unsubstituted alkylene, substituted fluoroalkylene, unsubstituted fluoroalkylene, substituted cycloalkylene, unsubstituted cycloalkylene, substituted heteroaryl or unsubstituted heteroaryl.

[0036] Preferably, the core backbone of the siloxane compound has 2-8 branches, more preferably 4-7.

[0037] Preferably, the phosphazene compound and the siloxane compound contain fluorinated branches;

[0038] Preferably, the fluorinated branch is a fluoroalkyl group substituted or unsubstituted, a fluoroalkoxy group substituted or unsubstituted, a fluoroalkylsilyloxy group substituted or unsubstituted, a fluorocycloalkyl group substituted or unsubstituted, a fluoroaryl group substituted or unsubstituted, or an aryl group substituted or unsubstituted.

[0039] The substituents are fluorine atoms, -CH3, -C(CH3), -C(CF3), -CF3, -CH2F2, -CHF2, -CH2CH3, -CH2CH2CH3, -O-CH3, -O-CH2CH3, -O-(CH2)2CH3, -O-(CH2)3CH3, -O-(CH2)4CH3, -O-(CH2)5CH3, -O-CF3, -O-CH2CF3, -O-(CH2)2CF3, -O-(CH2)3CF3, -O-(CH2)4CF3, -O-(CH2)5CF3, -O-CF2CF3, -O-(CF2)2CF3, -O-(CF2)3CF3, -O-(CF2)4CF3, -O-(CF2)5CF3, -CF2CF3, -CF2CF2CF3, -CF2CF2CF2CF3;

[0040] Preferably, the fluoroalkyl group substituted or unsubstituted comprises at least one of CF, CF2, CF3 or CF2H units.

[0041] Preferably, the fluoroalkyl group substituted or unsubstituted is selected from at least one of the following fluorocarbon units: CF, CF2, CF3 and CF2H units, more preferably CF2, CF3 and CF2H units, and even more preferably CF3 and CF2H units.

[0042] Preferably, the fluorine-containing branched chain has a fluorine atom content of not less than 20;

[0043] Preferably, the fluorine-containing branched SP 3 There must be at least 20 carbon atoms;

[0044] Preferably, the fluorinated branch is a fluorinated C1-C chain that is substituted or unsubstituted. 20 Alkyl groups, substituted or unsubstituted fluorinated C1-C groups 20 Alkoxy groups, substituted or unsubstituted fluorinated C1-C groups20 Alkylsilyloxy, fluorinated C5-C with or without substituents 20 Cycloalkyl, substituted or unsubstituted fluoroC6-C 30 Aryl, substituted or unsubstituted C6-C 30 Aryl.

[0045] Preferably, the fluorinated branch is a fluorinated C1-C chain that is substituted or unsubstituted. 10 Alkyl groups, substituted or unsubstituted fluorinated C1-C groups 10 Alkoxy groups, substituted or unsubstituted fluorinated C1-C groups 10 Alkylsilyloxy, fluorinated C5-C with or without substituents 10 Cycloalkyl, substituted or unsubstituted fluoroC6-C 18 Aryl, substituted or unsubstituted C6-C 18 Aryl.

[0046] Furthermore, the phosphazene compound is represented by the structure shown in formula (C-1) or formula (C-2):

[0047] (C-1) (C-2)

[0048] In equations (C-1) and (C-2), R1-R 14 The same or different atoms are selected from hydrogen atoms, C1-C 20 Straight-chain fluorinated alkyl groups, C1-C 20 Straight-chain fluorinated alkoxy groups, C3-C 20 Branched fluorinated cyclic alkyl groups, C3-C 20 Fluorinated cyclic alkyl groups, C3-C 20 Branched fluorinated cyclic alkoxy groups or C3-C 20 Fluorinated cyclic alkoxy groups;

[0049] The siloxane is represented by the structure shown in formula (C-3):

[0050] (C-3)

[0051] In equation (C-3), R 15 -R 22 The same or different atoms are selected from hydrogen atoms, C1-C 20 Straight-chain fluorinated alkyl groups, C1-C 20 Straight-chain fluorinated alkoxy groups, C3-C 20 Branched fluorinated cyclic alkyl groups, C3-C 20 Fluorinated cyclic alkyl groups, C3-C 20 Branched fluorinated cyclic alkoxy groups or C3-C20 Fluorinated cyclic alkoxy groups.

[0052] Furthermore, the R1-R 22 The same or different are selected from hydrogen atoms or the structure shown in formula (a-1):

[0053] Equation (a-1)

[0054] In equation (a-1), L1 represents a single bond, an oxygen atom, and C1-C. 20 C1-C with alkylene or fluorine atom substitution 20 Alkylene, C1-C 20 C1-C substituted with alkoxide or fluorine atom 20 Alkyloxy;

[0055] f = 0 or 1;

[0056] X1, X2, X3, X4, X5, and X6 are each independently represented as a hydrogen atom, a fluorine atom, or a C1-C atom substituted or unsubstituted. 20 Straight-chain alkyl groups, C3-C substituted or unsubstituted 20 Branched alkyl groups, substituted or unsubstituted C3-C 10 Cyclic alkyl, substituted or unsubstituted C1-C 20 Straight-chain alkoxy, substituted or unsubstituted C3-C 20 Branched alkoxy, substituted or unsubstituted C3-C 20 Cyclic alkoxy groups;

[0057] h = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0058] v = 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0059] t = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0060] The substituents are selected from C1-C atoms, substituted or unsubstituted fluorine atoms. 20 Straight-chain alkyl, fluorine-substituted or unsubstituted C3-C 20 Branched alkyl groups.

[0061] Furthermore, in equation (a-1), h+v+t≥3; preferably h+v+t≥4; preferably h+v+t≥5; preferably h+v+t≥6; preferably h+v+t≥7; preferably h+v+t≥8; preferably h+v+t≥9; preferably h+v+t≥10; preferably h+v+t≥11.

[0062] Preferably, the R1-R 22The atoms that are the same or different are selected from: hydrogen atom, -O-CH3, -O-CH2CH3, -O-(CH2)2CH3, -O-(CH2)3CH3, -O-(CH2)4CH3, -O-(CH2)5CH3, -O-(CH2)6CH3, -O(CH2)7CH3, -O(CH2)8CH3, -O(CH2)9CH3, -O(CH2) 10 CH3, -CH2CH3, -(CH2)2CH3, -(CH2)3CH3, -(CH2)4CH3, -(CH2)5CH3, -(CH2)6CH3, -(CH2)7CH3, -(CH2)8CH3, -(CH2)9CH3, -(CH2) 10 CH3, -CF2CF3, -(CF2)2CF3, -(CF2)3CF3, -(CF2)4CF3, -(CF2)5CF3, -(CF2)6CF3, -(CF2)7CF3, -(CF2)8CF3, -(CF2)9CF3, -(CF2) 10 CF3, -CH2CF2CF3, -CH2(CF2)2CF3, -CH2(CF2)3CF3, -CH2(CF2)4CF3, -CH2(CF2)5CF3, -CH2(CF2)6CF3, -CH2(CF2)7CF3, -CH2(CF2)8CF3, -CH2(CF2)9CF3, -CH2(CF2) 10 CF3, -(CH2)2CF2CF3, -(CH2)2(CF2)2CF3, -(CH2)2(CF2)3CF3, -(CH2)2(CF2)4CF3, -(CH2)2(CF2)5C F3, -(CH2)2(CF2)6CF3, -(CH2)2(CF2)7CF3, -(CH2)2(CF2)8CF3, -(CH2)2(CF2)9CF3, -(CH2)2(CF2) 10 CF3, -(CH2)3CF2CF3, -(CH2)3(CF2)2CF3, -(CH2)3(CF2)3CF3, -(CH2)3(CF2)4CF3, -(CH2)3(CF2)5C F3, -(CH2)3(CF2)6CF3, -(CH2)3(CF2)7CF3, -(CH2)3(CF2)8CF3, -(CH2)3(CF2)9CF3, -(CH2)3(CF2) 10CF3、-(CH2)4CF2CF3、-(CH2)4(CF2)2CF3、-(CH2)4(CF2)3CF3、-(CH2)4(CF2)4CF3、-(CH2)4(CF2)5CF3、-(CH2)4(CF2)6CF3、-(CH2)4(CF2)7CF3、-(CH2)4(CF2)8CF3、-(CH2)4(CF2)9CF3、-(CH2)4(CF2) 10 -CF3、-O-CF2CF3、-O-(CF2)2CF3、-O-(CF2)3CF3、-O-(CF2)4CF3、-O-(CF2)5CF3、-O-(CF2)6CF3、-O-(CF2)7CF3、-O-(CF2)8CF3、-O-(CF2)9CF3、-O-(CF2) 10 CF3、-O-CH2CF2CF3、-O-CH2(CF2)2CF3、-O-CH2(CF2)3CF3、-O-CH2(CF2)4CF3、-O-CH2(CF2)5CF3、-O-CH2(CF2)6CF3、-O-CH2(CF2)7CF3、-O-CH2(CF2)8CF3、-O-CH2(CF2)9CF3、-O-CH2(CF2) 10 CF3、-O-(CH2)2CF2CF3、-O-(CH2)2(CF2)2CF3、-O-(CH2)2(CF2)3CF3、-O-(CH2)2(CF2)4CF3、-O-(CH2)2(CF2)5CF3、-O-(CH2)2(CF2)6CF3、-O-(CH2)2(CF2)7CF3、-(CH2)2(CF2)8CF3、-O-(CH2)2(CF2)9CF3、-O-(CH2)2(CF2) 10 CF3、-(CH2)3CF2CF3、-(CH2)3(CF2)2CF3、-(CH2)3(CF2)3CF3、-(CH2)3(CF2)4CF3、-(CH2)3(CF2)5CF3、-(CH2)3(CF2)6CF3、-O-(CH2)3(CF2)7CF3、-O-(CH2)3(CF2)8CF3、-O-(CH2)3(CF2)9CF3、-O-(CH2)3(CF2) 10CF3、-O-(CH2)4CF2CF3、-O-(CH2)4(CF2)2CF3、-O-(CH2)4(CF2)3CF3、-O-(CH2)4(CF2)4CF3、-O-(CH2)4(CF2)5CF3、-O-(CH2)4(CF2)6CF3、-O-(CH2)4(CF2)7CF3、-O-(CH2)4(CF2)8CF3、-O-(CH2)4(CF2)9CF3、-O-(CH2)4(CF2) 10 CF3、-CF2CF2H、-(CF2)2CF2H、-(CF2)3CF2H、-(CF2)4CF2H、-(CF2)5CF2H、-(CF2)6CF2H、-(CF2)7CF2H、-(CF2)8CF2H、-(CF2)9CF2H、-(CF2) 10 CF2H、-CH2CF2CF2H、-CH2(CF2)2CF2H、-CH2(CF2)3CF2H、-CH2(CF2)4CF2H、-CH2(CF2)5CF2H、-CH2(CF2)6CF2H、-CH2(CF2)7CF2H、-CH2(CF2)8CF2H、-CH2(CF2)9CF2H、-CH2(CF2) 10 CF2H、-(CH2)2CF2CF2H、-(CH2)2(CF2)2CF2H、-(CH2)2(CF2)3CF2H、-(CH2)2(CF2)4CF2H、-(CH2)2(CF2)5CF2H、-(CH2)2(CF2)6CF2H、-(CH2)2(CF2)7CF2H、-(CH2)2(CF2)8CF2H、-(CH2)2(CF2)9CF2H、-(CH2)2(CF2) 10 CF2H、-(CH2)3CF2CF2H、-(CH2)3(CF2)2CF2H、-(CH2)3(CF2)3CF2H、-(CH2)3(CF2)4CF2H、-(CH2)3(CF2)5CF2H、-(CH2)3(CF2)6CF2H、-(CH2)3(CF2)7CF2H、-(CH2)3(CF2)8CF2H、-(CH2)3(CF2)9CF2H、-(CH2)3(CF2) 10CF2H、-(CH2)4CF2CF2H、-(CH2)4(CF2)2CF2H、-(CH2)4(CF2)3CF2H、-(CH2)4(CF2)4CF2H、-(CH2)4(CF2)5CF2H、-(CH2)4(CF2)6CF2H、-(CH2)4(CF2)7CF2H、-(CH2)4(CF2)8CF2H、-(CH2)4(CF2)9CF2H、-(CH2)4(CF2) 10 -CF2H、-O-CF2CF2H、-O-(CF2)2CF2H、-O-(CF2)3CF2H、-O-(CF2)4CF2H、-O-(CF2)5CF2H、-O-(CF2)6CF2H、-O-(CF2)7CF2H、-O-(CF2)8CF2H、-O-(CF2)9CF2H、-O-(CF2) 10 CF2H、-O-CH2CF2CF2H、-O-CH2(CF2)2CF2H、-O-CH2(CF2)3CF2H、-O-CH2(CF2)4CF2H、-O-CH2(CF2)5CF2H、-O-CH2(CF2)6CF2H、-O-CH2(CF2)7CF2H、-O-CH2(CF2)8CF2H、-O-CH2(CF2)9CF2H、-O-CH2(CF2) 10 CF2H、-O-(CH2)2CF2CF2H、-O-(CH2)2(CF2)2CF2H、-O-(CH2)2(CF2)3CF2H、-O-(CH2)2(CF2)4CF2H、-O-(CH2)2(CF2)5CF2H、-O-(CH2)2(CF2)6CF2H、-O-(CH2)2(CF2)7CF2H、-(CH2)2(CF2)8CF2H、-O-(CH2)2(CF2)9CF2H、-O-(CH2)2(CF2) 10 CF2H、-(CH2)3CF2CF2H、-(CH2)3(CF2)2CF2H、-(CH2)3(CF2)3CF2H、-(CH2)3(CF2)4CF2H、-(CH2)3(CF2)5CF2H、-(CH2)3(CF2)6CF2H、-O-(CH2)3(CF2)7CF2H、-O-(CH2)3(CF2)8CF2H、-O-(CH2)3(CF2)9CF2H、-O-(CH2)3(CF2) 10CF2H, -O-(CH2)4CF2CF2H, -O-(CH2)4(CF2)2CF2H, -O-(CH2)4(CF2)3CF2H, -O-(CH2)4(CF2)4CF2H, -O-(CH2)4(CF2)5C F2H, -O-(CH2)4(CF2)6CF2H, -O-(CH2)4(CF2)7CF2H, -O-(CH2)4(CF2)8CF2H, -O-(CH2)4(CF2)9CF2H, -O-(CH2)4(CF2) 10 CF2H.

[0063] Preferably, the first cover layer comprises the following structure:

[0064] (C1) (C2)

[0065] (C3) (C4)

[0066] (C5) (C6)

[0067] (C7) (C8)

[0068] (C9) (C10)

[0069] (C11) (C12)

[0070] (C13) (C14)

[0071] (C15) (C16)

[0072] (C17)

[0073] (C18)

[0074] (C19)

[0075] (C20)

[0076] (C21)

[0077] (C22)

[0078] (C23)

[0079] (C24)

[0080] (C25)

[0081] (C26)

[0082] (C27)

[0083] (C28)

[0084] (C29)

[0085] (C30)

[0086] (C31)

[0087] (C32)

[0088] (C33)

[0089] (C34)

[0090] (C35)

[0091] (C36)

[0092] (C37)

[0093] (C38)

[0094] (C39)

[0095] (C40)

[0096] (C41)

[0097] (C42) (C43)

[0098] (C44) (C45)

[0099] (C46) (C47)

[0100] (C48) (C49)

[0101] (C50)

[0102] (C51)

[0103] (C52)

[0104] (C53)

[0105] (C54)

[0106] (C55)

[0107] (C56)

[0108] (C57)

[0109] (C58)

[0110] (C59)

[0111] (C60)

[0112] (C61)

[0113] (C62)

[0114] (C63)

[0115] (C64)

[0116] (C65)

[0117] (C66)

[0118] (C67)

[0119] (C68)

[0120] (C69)

[0121] (C70)

[0122] (C71)

[0123] (C72)

[0124] (C73)

[0125] (C74)

[0126] (C75)

[0127] (C76)

[0128] (C77)

[0129] (C78)

[0130] (C79)

[0131] (C80)

[0132] (C81)

[0133] (C82)

[0134] (C83)

[0135] (C84)

[0136] (C85)

[0137] (C86)

[0138] (C87)

[0139] (C88)

[0140] (C89)

[0141] (C90)

[0142] (C91)

[0143] (C92)

[0144] (C93)

[0145] (C94)

[0146] (C95)

[0147] (C96)

[0148] (C97)

[0149] (C98)

[0150] (C99)

[0151] (C100)

[0152] (C101)

[0153] One or more of (C102).

[0154] Furthermore, the material in the second covering layer is selected from the structure shown in general formula (B-1) or (B-2):

[0155] General formula (B-1)

[0156] In general formula (B-1), R represents F, , , , , or ;

[0157] Ar1 represents C1-C, substituted or unsubstituted. 20 Alkyl groups, substituted or unsubstituted C1-C 20 Alkoxy, substituted or unsubstituted aromatic amino groups, substituted or unsubstituted C6-C 30 Aryl, substituted or unsubstituted C2-C 30 heteroaryl, substituted or unsubstituted C6-C 30 Silyl aryl, C2-C substituted or unsubstituted 30 Silyl aryl, C6-C substituted or unsubstituted 30 aryl ether group, C2-C group substituted or unsubstituted 30 heteroaryl ethers;

[0158] Each occurrence of n, whether the same or different, is represented independently as 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30;

[0159] Each occurrence of y, whether the same or different, is independently represented as 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13;

[0160] Each occurrence of j, whether the same or different, is independently represented as 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10;

[0161] Each occurrence of Y2 or Y3 being the same or different is independently represented as CR. 21 Or N;

[0162] The R 21 Each instance of the same or different element is represented by a hydrogen atom, deuterium atom, halogen atom, cyano group, or C1-C atoms that are substituted or unsubstituted. 20 Alkyl groups, substituted or unsubstituted C1-C 20 Alkoxy groups, C1- groups substituted or unsubstituted 20 Silyl, C1-C substituted or unsubstituted 20 Silyloxy group, substituted or unsubstituted C6-C 30 Aryl, substituted or unsubstituted C2-C 30 Mixed aromatics;

[0163] The substituent is selected from deuterium, halogen, cyano, trifluoromethyl, trifluoromethoxy, halogen-substituted or unsubstituted C1-C. 20 Alkyl, halogen-substituted or unsubstituted C1-C 20 alkoxy, halogen-substituted or unsubstituted C1-C 20 Silyl, halogen-substituted or unsubstituted C1-C 20 Silyloxy group, C6-C 30 arylamine, C2-C 30 heteroarylamine, C6-C 30 Silylaryl, C2-C 30 Silyl aryl, C6-C 30 Aryl, C2-C 30 One or more of the heteroaryl groups;

[0164] General formula (B-2)

[0165] In general formula (B-2), La is selected from the following structures:

[0166] , ,

[0167] Ar2 and Ar3 represent hydrogen atoms, fluorine atoms, trifluoromethyl groups, and C1-C atoms that are substituted or unsubstituted. 20 Alkyl groups, substituted or unsubstituted C6-C 30 Aryl, substituted or unsubstituted C2-C 30 Heteroaryl, arylamine group substituted or unsubstituted, or the structure shown in formula a;

[0168]

[0169] Formula a

[0170] In formula a, L c Represents a single bond, a C6-C bond substituted with a substituent, or an unsubstituted bond. 30 arylene, C2-C substituted or unsubstituted 30 Heteroaryl, C6-C substituted or unsubstituted 30 arylene amino group, or C2-C group substituted or unsubstituted. 30 heteroarylamine;

[0171] p = 0, 1, 2, 3, 4 or 5;

[0172] q = 1, 2, 3, 4 or 5; a = 0, 1, 2, 3, 4 or 5; and q + a ≥ 2;

[0173] k = 1, 2, 3, 4 or 5; b = 0 or 1;

[0174] Each occurrence of Y2 or Y3 being the same or different is independently represented as CR. 21 Or N;

[0175] The R 21 Each instance of the same or different element is represented by a hydrogen atom, deuterium atom, halogen atom, cyano group, or C1-C atoms that are substituted or unsubstituted. 20 Alkyl groups, substituted or unsubstituted C1-C 20 Alkoxy groups, C1- groups substituted or unsubstituted 20 Silyl, C1-C substituted or unsubstituted 20 Silyloxy group, substituted or unsubstituted C6-C 30 Aryl, substituted or unsubstituted C2-C 30 Mixed aromatics;

[0176] The substituent is selected from deuterium, halogen, cyano, trifluoromethyl, trifluoromethoxy, halogen-substituted or unsubstituted C1-C. 20 Alkyl, halogen-substituted or unsubstituted C1-C 20 alkoxy, halogen-substituted or unsubstituted C1-C 20 Silyl, halogen-substituted or unsubstituted C1-C 20 Silyloxy group, C6-C 30 arylamine, C2-C 30 heteroarylamine, C6-C 30 Silylaryl, C2-C 30 Silyl aryl, C6-C 30 Aryl, C2-C 30 One or more of the heteroaryl groups.

[0177] Preferably, Ar2 and Ar3 represent hydrogen atoms, fluorine atoms, trifluoromethyl, trifluoromethyl-substituted phenyl, fluorine-substituted phenyl, trifluoromethyl and fluorine-substituted phenyl.

[0178] Preferably, the material of the second covering layer may be selected from the structure shown in general formula (II-1) or (II-2);

[0179] (II-1)

[0180] (II-2)

[0181] In general formulas (II-1) and (II-2), R is represented by F, , , , , or ;

[0182] n2, n3, and n4 can be independently represented as 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15;

[0183] m2 and m3 can be independently represented as 0, 1, 2, 3, 4, 5 or 6;

[0184] k3, k4, k5, and k6 can be independently represented as 0, 1, 2, 3, 4, or 5;

[0185] j2, j3, and j4 can be independently represented as 0, 1, 2, 3, 4, or 5;

[0186] s represents 0, 1, 2, 3 or 4;

[0187] Each occurrence of Y2 or Y3 being the same or different is independently represented as CR.21 Or N;

[0188] The R 21 Each instance of the same or different element is represented by a hydrogen atom, deuterium atom, halogen atom, cyano group, or C1-C atoms that are substituted or unsubstituted. 20 Alkyl groups, substituted or unsubstituted C1-C 20 Alkoxy groups, C1- groups substituted or unsubstituted 20 Silyl, C1-C substituted or unsubstituted 20 Silyloxy group, substituted or unsubstituted C6-C 30 Aryl, substituted or unsubstituted C2-C 30 Mixed aromatics;

[0189] L3, L4, L5, L6, and L7 are each independently represented as single bonds, substituted with substituents, or unsubstituted C1-C bonds. 20 Alkylene, C1-C substituted or unsubstituted 20 alkeneoxy group, C6-C substituted or unsubstituted 30 arylene, C6-C substituted or unsubstituted 30 Silenearyl, C2-C substituted or unsubstituted 30 Silene-heteroaryl, C6-C substituted or unsubstituted 30 arylene ether group, C2-C group substituted or unsubstituted 30 Heteroarylene ethers, or C2-C groups substituted or unsubstituted. 30 Heteroaryl; preferably, L2, L3, L4, L5, L6 and L7 are each independently represented as a single bond, a phenylene substituted or unsubstituted with a substituent, a diphenylene substituted or unsubstituted with a substituent, a carbazolyl substituted or unsubstituted with a substituent, or a terphenylene substituted or unsubstituted with a substituent.

[0190] Each occurrence of L8, whether identical or different, is independently represented as a silicon atom (Si), a nitrogen atom (N), a single bond, or a C6-C bond substituted or unsubstituted. 30 arylene, C2-C substituted or unsubstituted 30 Silenearyl, C2-C substituted or unsubstituted 30 Silene-heteroaryl, C6-C substituted or unsubstituted 30 arylene ether group, C2-C group substituted or unsubstituted 30 Heteroarylene ethers, C2-C substituted or unsubstituted groups 30 Heteroaryl, C6-C substituted or unsubstituted 30arylamine group, C2-C substituted or unsubstituted 30 heteroarylamine;

[0191] Ar4, Ar5, Ar6, and Ar7 are each independently represented as hydrogen atoms, C1-C atoms substituted or unsubstituted. 20 Alkyl groups, substituted or unsubstituted C1-C 20 Alkoxy, C6-C substituted or unsubstituted 30 Aryl, substituted or unsubstituted C6-C 30 Silyl aryl, C2-C substituted or unsubstituted 30 Silyl aryl, C6-C substituted or unsubstituted 30 aryl ether group, C2-C group substituted or unsubstituted 30 heteroaryl ethers, C2-C substituted or unsubstituted groups 30 Heteroaryl; preferably, Ar4, Ar5, Ar6, and Ar7 are each independently represented as a single bond, a phenyl group substituted or unsubstituted with a substituent, a diphenyl group substituted or unsubstituted with a substituent, a carbazolyl group substituted or unsubstituted with a substituent, a terphenyl group substituted or unsubstituted with a substituent, a tetraphenylene group substituted or unsubstituted with a substituent, or a pentaphenyl group substituted or unsubstituted with a substituent;

[0192] The substituents are optionally selected from deuterium atoms, halogen atoms, cyano groups, fluorine atoms, trifluoromethyl groups, halogen-substituted or unsubstituted C1-C groups. 20 Alkyl, halogen-substituted or unsubstituted C1-C 20 alkoxy, halogen-substituted or unsubstituted C1-C 20 Silyl, halogen-substituted or unsubstituted C1-C 20 Silyloxy group, C6-C 30 Aryl and C2-C 30 One or more of the heteroaryl groups;

[0193] The C2-C 30 heteroaryl, C2-C 30 heteroaryl, C2-C 30 Silyl aryl, C2-C 30 Silene-aryl, C2-C 30 heteroarylamine, C2-C 30 Heteroarylene ethers and C2-C 30 The heteroatoms in the heteroaryl group are selected from nitrogen, oxygen, sulfur, phosphorus or fluorine.

[0194] Preferably, L8 is made of Si, N,

[0195] , , ,

[0196] , , ,

[0197] , or ;

[0198] Y8, Y9, Y 10 Y 11 Y 12 Y 13 Y 14 Y 15 and Y 16 Each occurrence of the same or different elements is independently represented as C-Re or N; two adjacent Y8, Y9, Y... 10 Y 11 Y 12 Y 13 Y 14 Y 15 and Y 16 They can also be linked into benzene rings or linked into heteroatom rings;

[0199] When connected with other groups, the Y8, Y9, and Y6 groups at the connection point... 10 Y 11 Y 12 Y 13 Y 14 Y 15 and Y 16 Each is independently represented as a carbon atom;

[0200] X 20 Each can be independently represented as a dimethyl-substituted or unsubstituted methylene, -O-, -S-, or -N(Rs)-;

[0201] The Rs is represented as C1-C 20 Alkyl, C6-C 30 Aryl, C2-C 30 Mixed aromatics;

[0202] m20 and m21 are each independently represented as 1, 2 or 3;

[0203] A1 and A2 are each independently represented as C1-C with hydrogen atoms, halogen substitution, or no substitution. 20 Alkyl, cyano or halogen, preferably hydrogen atom, methyl, trifluoromethyl, cyano or fluorine;

[0204] Re can be represented independently as a hydrogen atom, deuterium atom, halogen atom, cyano group, fluorine atom, methyl group, trifluoromethyl group, or halogen-substituted or unsubstituted C1-C group.20 Alkyl, halogen-substituted or unsubstituted C1-C 20 alkoxy, halogen-substituted or unsubstituted C1-C 20 Silyl or halogen substituted or unsubstituted C1-C 20 Silyloxy group.

[0205] Preferably, the material of the second covering layer may be selected from any of the following organic compounds:

[0206] (B1) (B2) (B3)

[0207] (B4) (B5) (B6)

[0208] (B7) (B8) (B9)

[0209] (B10) (B11)

[0210] (B12) (B13)

[0211] (B14) (B15)

[0212] (B16) (B17) (B18)

[0213] (B19) (B20) (B21)

[0214] (B22) (B23) (B24)

[0215] (B25) (B26) (B27)

[0216] (B28) (B29) (B30)

[0217] (B31) (B32) (B33)

[0218] (B34) (B35) (B36)

[0219] (B37) (B38)

[0220] (B39) (B40)

[0221] (B41) (B42)

[0222] (B43) (B44)

[0223] (B45) (B46)

[0224] (B47) (B48)

[0225] (B49) (B50)

[0226] (B51) (B52)

[0227] (B53) (B54)

[0228] (B55) (B56)

[0229] (B57) (B58)

[0230] (B59) (B60)

[0231] (B61) (B62)

[0232] (B63) (B64)

[0233] (B65) (B66)

[0234] (B67) (B68)

[0235] (B69) (B70)

[0236] (B71) (B72).

[0237] Furthermore, the material in the third covering layer can be selected from the structures shown in general formulas (A-1), (A-2), (A-3), (A-4), or (A-5):

[0238]

[0239] (A-1) (A-2) (A-3)

[0240]

[0241] (A-4) (A-5)

[0242] In general formulas (A-1), (A-2), (A-3), (A-4), and (A-5), L 30 L 31 L 32 L 33 Each can be represented independently as a single bond, a C6-C bond substituted with a substituent, or an unsubstituted bond. 30 arylene, C2-C substituted or unsubstituted 30 heteroaryl;

[0243] L 34 Represented as C6-C with or without substituents. 30 arylene, C2-C substituted or unsubstituted 30 heteroaryl;

[0244] M represents the C6-C column, which may or may not be substituted with a substituent. 30 Aryl, substituted or unsubstituted C2-C 30 Mixed aromatics;

[0245] X is represented independently as O, S, or NR. 30 ;

[0246] Each occurrence of Z, whether identical or different, is independently represented as CR. 31 ;

[0247] Each occurrence of Y, whether identical or different, is independently represented by N or CR. 32 ;

[0248] The R 30 Represented as C6-C with or without substituents. 30 Aryl, substituted or unsubstituted C2-C 30 Mixed aromatics;

[0249] The R 31 R 32 Ar 31 Ar 32 Ar 33 Each can be represented independently as a hydrogen atom, a C1-C atom substituted with a substituent, or an unsubstituted atom. 20 Alkyl groups, substituted or unsubstituted C2-C 20 Alkenyl, C6-C substituted or unsubstituted 30 Aryl, substituted or unsubstituted C2-C 30 Heteroaryl, arylamine group substituted or unsubstituted;

[0250] M represents the C6-C column, which may or may not be substituted with a substituent. 30 Aryl, substituted or unsubstituted C2-C 30 Mixed aromatics;

[0251] The substituents are selected from C6-C6. 30 Aryl, C2-C 30 One or more of the heteroaryl groups.

[0252] Preferably, the material of the third covering layer can be selected from the structure shown in general formula (A-3-1), (A-4-1), or (A-5-1);

[0253]

[0254] (A-3-1) (A-4-1) (A-5-1)

[0255] In general formulas (A-3-1), (A-4-1), and (A-5-1), the L 30 L 31 L 32 X, Z, Ar 31 Ar 32 The meaning is the same as above.

[0256] Preferably, M represents benzofuranyl (substituted or unsubstituted), benzoisoxazolyl (substituted or unsubstituted), phenyl (substituted or unsubstituted), benzothiazolyl (substituted or unsubstituted), dibenzothiophene (substituted or unsubstituted), triphenylene (substituted or unsubstituted), dibenzofuranyl (substituted or unsubstituted), pyridyl (substituted or unsubstituted), quinolinyl (substituted or unsubstituted), isoquinolinyl (substituted or unsubstituted), naphthyl (substituted or unsubstituted), or phenanthrene (substituted or unsubstituted).

[0257] Preferably, the L 30 L 31 L 32 L 33 Each can be represented independently as a single bond, a phenylene group substituted or unsubstituted with a substituent, a diphenylene group substituted or unsubstituted with a substituent, a carbazolyl group substituted or unsubstituted with a substituent, a naphthofuran group substituted or unsubstituted with a substituent, a dimethylfluorene group substituted or unsubstituted with a substituent, a diphenylfluorene group substituted or unsubstituted with a substituent, a 9,9'-spirobifluorene group substituted or unsubstituted with a substituent, a terphenylene group substituted or unsubstituted with a substituent, a dibenzofuran group substituted or unsubstituted with a substituent, a dibenzothiophene group substituted or unsubstituted with a substituent, a phenanthrene group substituted or unsubstituted with a substituent, a 9,10-benzophenanthrene group substituted or unsubstituted with a substituent, and a naphtho[2,1-b]furan group substituted or unsubstituted with a substituent.

[0258] The L 34 Represented as phenylene with or without substituents, diphenylene with or without substituents, carbazolyl with or without substituents, naphthofuran with or without substituents, dimethylfluorene with or without substituents, diphenylfluorene with or without substituents, 9,9'-spirofluorene with or without substituents, terphenylene with or without substituents, dibenzofuran with or without substituents, dibenzothiophene with or without substituents, phenanthrene with or without substituents, 9,10-benzophenanthrene with or without substituents, and naphtho[2,1-b]furan with or without substituents.

[0259] Preferably, the R 30Represented as benzoxazolyl (substituted or unsubstituted), diphenylamino (substituted or unsubstituted), benzofuranyl (substituted or unsubstituted), benzoisoxazolyl (substituted or unsubstituted), phenyl (substituted or unsubstituted), biphenyl (substituted or unsubstituted), benzothiazolyl (substituted or unsubstituted), dibenzothiophene (substituted or unsubstituted), triphenylene (substituted or unsubstituted), dibenzofuranyl (substituted or unsubstituted), carbazole (substituted or unsubstituted), pyridyl (substituted or unsubstituted), pyrene (substituted or unsubstituted), quinolinyl (substituted or unsubstituted), isoquinolinyl (substituted or unsubstituted), naphthyl (substituted or unsubstituted), and so on. Substituted or unsubstituted phenanthryl, 9,10-benzophenanthryl substituted or unsubstituted, dibenzothiophene substituted or unsubstituted, indole[1,2-f]phenanthryl substituted or unsubstituted, imidazo[2,1-a]isoquinolinyl substituted or unsubstituted, imidazo[1,2-a]quinolinyl substituted or unsubstituted, benzo[4,5]imidazo[1,2-a]pyridyl substituted or unsubstituted, imidazo[1,2-a]pyridyl substituted or unsubstituted, benzofuran[3,2-c]quinolinyl substituted or unsubstituted, naphtho[1,2-b]benzofuranyl substituted or unsubstituted, naphtho[2,3-b]benzofuranyl substituted or unsubstituted.

[0260] The R 31 R 32 Ar 31 Ar 32 Ar 33Each of the following is represented independently as a hydrogen atom, benzoxazolyl (substituted or unsubstituted), diphenylamino (substituted or unsubstituted), benzofuranyl (substituted or unsubstituted), benzoisoxazolyl (substituted or unsubstituted), phenyl (substituted or unsubstituted), biphenyl (substituted or unsubstituted), benzothiazolyl (substituted or unsubstituted), dibenzothiophene (substituted or unsubstituted), triphenylene (substituted or unsubstituted), dibenzofuranyl (substituted or unsubstituted), carbazoleyl (substituted or unsubstituted), pyridyl (substituted or unsubstituted), pyreneyl (substituted or unsubstituted), quinolinyl (substituted or unsubstituted), isoquinolinyl (substituted or unsubstituted), and so on. Naphthyl, phenanthryl substituted or unsubstituted, 9,10-benzophenanthryl substituted or unsubstituted, dibenzothiophene substituted or unsubstituted, indole[1,2-f]phenanthryl substituted or unsubstituted, imidazo[2,1-a]isoquinolinyl substituted or unsubstituted, imidazo[1,2-a]quinolinyl substituted or unsubstituted, benzo[4,5]imidazo[1,2-a]pyridyl substituted or unsubstituted, imidazo[1,2-a]pyridyl substituted or unsubstituted, benzofuran[3,2-c]quinolinyl substituted or unsubstituted, naphtho[1,2-b]benzofuranyl substituted or unsubstituted, naphtho[2,3-b]benzofuranyl substituted or unsubstituted;

[0261] The substituent is selected from one or more of phenyl, naphthyl, diphenyl, terphenyl, pyridyl, pyrazinyl, pyridazinyl, quinolinyl, isoquinolinyl, benzoxazolyl, benzothiazolyl, benzoimidazolyl, quinoxolinyl, quinazolinyl, cyclolinyl, naphthinyl, fluorenyl, dibenzofuranyl, N-phenylcarbazolyl, dibenzothiophenyl, naphthiophenyl, naphthiophenyl, imidazo[1,2-a]pyridyl, imidazo[2,1-a]isoquinolinyl, imidazo[1,2-a]quinolinyl, and imidazo[1,2-b]isoquinolinyl.

[0262] Preferably, the material of the third capping layer may be selected from any of the following organic compounds:

[0263] (A1) (A2) (A3)

[0264] (A4) (A5) (A6)

[0265] (A7) (A8) (A9)

[0266] (A10) (A11) (A12)

[0267] (A13) (A14) (A15)

[0268] (A16) (A17) (A18)

[0269] (A19) (A20) (A21)

[0270] (A22) (A23) (A24) (A25)

[0271] (A26) (A27) (A28) (A29)

[0272] (A30) (A31) (A32)

[0273] (A33) (A34) (A35)

[0274] (A36) (A37) (A38)

[0275] (A39) (A40) (A41)

[0276] (A42) (A43) (A44)

[0277] (A45) (A46) (A47)

[0278] (A48) (A49) (A50)

[0279] (A51) (A52) (A53)

[0280] (A54) (A55) (A56)

[0281] (A57) (A58) (A59)

[0282] (A60) (A61) (A62)

[0283] (A63) (A64) (A65)

[0284] (A66) (A67) (A68)

[0285] (A69) (A70) (A71)

[0286] (A72) (A73) (A74)

[0287] (A75) (A76) (A77)

[0288] (A78) (A79) (A80)

[0289] (A81) (A82) (A83)

[0290] (A84) (A85) (A86)

[0291] (A87) (A88) (A89)

[0292] (A90) (A91) (A92)

[0293] (A93) (A94) (A95)

[0294] (A96) (A97) (A98)

[0295] (A99) (A100)

[0296] (A101) (A102)

[0297] (A103) (A104)

[0298] (A105) (A106)

[0299] (A107) (A108) (A109)

[0300] (A110) (A111) (A112) (A113)

[0301] (A114) (A115) (A116)

[0302] (A117) (A118) (A119)

[0303] (A120) (A122) (A123)

[0304] (A124) (A125) (A126)

[0305] (A127) (A128) (A129)

[0306] (A130) (A131) (A132)

[0307] (A133) (A134) (A135)

[0308] (A136) (A137) (A138)

[0309] (A139) (A140) (A141)

[0310] (A142) (A143) (A144)

[0311] (A145) (A146) (A147)

[0312] (A148) (A149) (A150)

[0313] (A151) (A152) (A153)

[0314] (A154) (A155) (A156)

[0315] (A157) (A158) (A159)

[0316] (A160) (A161) (A162)

[0317] (A163) (A164) (A165)

[0318] (A166)

[0319] The present invention also provides a top-emitting organic electroluminescent device, comprising:

[0320] substrate;

[0321] A reflective electrode, wherein the reflective electrode is located on the substrate;

[0322] An organic functional layer is located above the reflective electrode;

[0323] A light-transmitting electrode, wherein the light-transmitting electrode is located on the organic functional layer;

[0324] A light extraction layer, wherein the light extraction layer is located above the light-transmitting electrode;

[0325] The light extraction layer is the light extraction layer described in this invention.

[0326] Preferably, the light-transmitting electrode comprises any one of Ag (silver), Mg (magnesium), Al (aluminum), and a magnesium-silver combination.

[0327] Technical advantages of this invention: The light extraction layer of this invention is provided with a first cover layer, a second cover layer and a third cover layer sequentially along the light emission direction, wherein the refractive index of the first cover layer is less than that of the second cover layer, the refractive index of the second cover layer is less than that of the third cover layer, the first cover layer contains a phosphazene compound or a siloxane compound, and the second cover layer contains a fluorinated organic compound. This light extraction layer structure can effectively improve the efficiency loss between interfaces, and the top-emitting organic electroluminescent device using this light extraction layer structure can effectively improve the device efficiency. Attached Figure Description

[0328] Figure 1A schematic cross-sectional view of a top-emitting organic light-emitting diode (OLED) 200 is shown.

[0329] The top-emitting organic light-emitting device (OLED) 200 includes a reflective electrode 201, an organic functional layer 202, a light-transmitting electrode 203, a first capping layer 204, a second capping layer 205, and a third capping layer 206.

[0330] Figure 2 A schematic cross-sectional view of the organic functional layer 202 of a top-emitting organic light-emitting device (OLED) is shown.

[0331] The organic functional layer 202 includes a hole injection layer 20210 (HIL), a hole transport layer 20220 (HTL), an electron blocking layer 20230 (EBL), a light emitting layer 20240 (EML), a hole blocking layer 20250 (HBL), an electron transport layer 20260 (ETL), and an electron injection layer 20270 (EIL). Detailed Implementation

[0332] Throughout this specification, unless explicitly stated otherwise, the term "including" any component will be understood to imply the inclusion of other components, not to exclude any other components. Furthermore, it should be understood that throughout this specification, when an element such as a layer, film, region, or substrate is referred to as being "on" or "above" another element, it may be "directly on" the other element, or there may be intermediate elements present. Additionally, "on" or "above" means located above the target portion, and not necessarily above it in the direction of gravity.

[0333] In this invention, the substituted or unsubstituted aromatic amino group refers to... Wherein Q1 and Q2 represent aromatic groups that are substituted or unsubstituted, and Q1 and Q2 preferably represent C6~C6 groups that are substituted or unsubstituted. 30 The aryl group may be substituted or unsubstituted at C2-C. 30 Mixed aromatic compounds.

[0334] In this invention, the C1- group, whether substituted or unsubstituted, is... 20 Silyl refers to Q3, Q4, and Q5 represent C1-C1 cells that are substituted or unsubstituted. 20 Alkyl groups or C3-C groups substituted or unsubstituted 20 Cycloalkyl.

[0335] In this invention, C6~C 30Aryl refers to an aryl group having 6 to 30 carbon atoms, preferably an aryl group having 6 to 18 carbon atoms, more preferably an aryl group having 6 to 12 carbon atoms, and preferably phenyl, naphthyl, diphenyl, terphenyl, anthracene, phenanthrene, dimethylfluorenyl, diphenylfluorenyl, spirofluorenyl, fused tetraphenyl, pyrene, phenyl, triphenylene, peryl, indene, 1,1,4,4-tetramethyl-1,2,3,4-tetrahydronaphthyl, or a combination thereof or a fused ring of the aforementioned groups, but is not limited thereto.

[0336] In this invention, C2~C 30 The heteroaryl group refers to a heteroaryl group having 2 to 30 carbon atoms, preferably a heteroaryl group having 2 to 20 carbon atoms, more preferably a heteroaryl group having 4 to 20 carbon atoms, more preferably a heteroaryl group having 4 to 12 carbon atoms, more preferably a heteroaryl group having 5 to 12 carbon atoms, and preferably furanyl, thiopheneyl, pyrroleyl, pyrazolyl, imidazolyl, triazolyl, oxazolyl, thiazolyl, oxadiazolyl, thiadiazolyl, pyridinyl, pyrimidinyl, pyrazinyl, triazinyl, or benzofuranyl. Benzothiophene, benzimidazolyl, indolyl, quinolinyl, isoquinolinyl, quinazolinyl, quinolinyl, quinoxolinyl, naphridinyl, benzoxazinyl, benzothiazinyl, benzopyrimidinyl, acridineyl, phenazinyl, phenthiazinyl, phenoxazinyl, fumonyl, dibenzofuranyl, dibenzothiophene, benzodibenzofuranyl, benzodibenzothiophene, carbazoyl, N-phenylcarbazoyl, benzoindolyl, and combinations thereof or combinations of the foregoing groups, but not limited thereto.

[0337] In this invention, the number of heteroatoms in the heteroaryl group is 1-5, preferably 1-4, preferably 1-3, preferably 1-2, and preferably 1.

[0338] In this invention, C1~C 20 Alkyl (including straight-chain alkyl and branched-chain alkyl) refers to an alkyl group having 1 to 20 carbon atoms, preferably an alkyl group having 1 to 10 carbon atoms, preferably an alkyl group having 1 to 6 carbon atoms, preferably an alkyl group having 1 to 5 carbon atoms, preferably an alkyl group having 1 to 4 carbon atoms, preferably methyl, ethyl, propyl, isopropyl, butyl, tert-butyl, isobutyl, sec-butyl, neopentyl, n-pentyl, isopentyl, tert-pentyl, octyl, heptyl, n-decyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl, 1-butylpentyl, 2-methylbutyl, etc., but not limited to these.

[0339] In this invention, C3~C 20 Cycloalkyl refers to monocyclic or polycyclic alkyl groups comprising 3 to 20 cyclic atoms, with the rings linked by single bonds or fused rings. In this document, C4-C is preferred. 20 cycloalkyl, C4-C 10 Cycloalkyl, more preferably C5-C 10cycloalkyl, more preferably C6-C 10 Cycloalkyl groups, non-limiting examples of which include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, 4-methylcyclohexyl, 4,4-dimethylcyclohexyl, adamantyl, and cycloheptyl, but are not limited thereto.

[0340] In this invention, the halogen refers to fluorine, chlorine, bromine or iodine.

[0341] In this invention, C1~C 20 Alkoxy groups include, but are not limited to, alkoxy, ethoxy, propoxy, butoxy, pentoxy, hexoxy, or isopropoxy.

[0342] In this invention, the substituents are selected from deuterium, chlorine, fluorine, adamantyl, cyano, methyl, ethyl, propyl, isopropyl, tert-amyl, tert-butyl, butyl, phenyl, diphenyl, naphthyl, anthracene, phenanthrene, pyridyl, pyrimidinyl, pyrazinyl, pyridazinyl, benzoxazolyl, benzothiazolyl, quinoxalinyl, quinolinyl, isoquinolinyl, furanyl, thiophene, indoleyl, pyrroleyl, and dibenzofuranyl. Dibenzothiophene, 9,9-dimethylfluorenyl, spirofluorenyl, carbazolyl, N-phenylcarbazolyl, carbazolinyl, azirphenanthrenel, diphenylamino, 1,1,4,4-tetramethyl-1,2,3,4-tetrahydronaphthyl, benzoindolyl, deuterated adamantyl, deuterated methyl, deuterated ethyl, deuterated propyl, deuterated isopropyl, deuterated tert-amyl, deuterated tert-butyl, deuterated... Butyl, deuterated phenyl, deuterated diphenyl, deuterated naphthyl, deuterated anthracene, deuterated phenanthryl, deuterated pyridyl, deuterated pyrimidinyl, deuterated pyrazinyl, deuterated pyridazinyl, deuterated benzoxazolyl, deuterated benzothiazolyl, deuterated quinoxalinyl, deuterated quinolinyl, deuterated isoquinolinyl, deuterated furanyl, deuterated thiopheneyl, deuterated indole One or more of the following: dolomyl, deuterated pyrroleyl, deuterated dibenzofuranyl, deuterated dibenzothiopheneyl, deuterated 9,9-dimethylfluorenyl, deuterated spirofluorenyl, deuterated carbazolyl, deuterated N-phenylcarbazolyl, deuterated carbazolinyl, deuterated azirophenonel, deuterated 1,1,4,4-tetramethyl-1,2,3,4-tetrahydronaphthyl, and deuterated benzoindolyl.

[0343] Top-emitting organic electroluminescent devices.

[0344] The top-emitting organic electroluminescent device of the present invention comprises, in sequence, a substrate, a reflective electrode, an organic functional layer, a light-transmitting electrode, and a light extraction layer. The organic functional layer includes a hole transport region thin film layer, a light-emitting region thin film layer, and an electron transport region thin film layer. The hole transport region thin film layer includes a hole injection layer, a hole transport layer, and an electron blocking layer. The electron transport region thin film layer includes a hole blocking layer, an electron transport layer, and an electron injection layer. Furthermore, a light-transmitting electrode is disposed on the electron injection layer, a first capping layer is disposed on the light-transmitting electrode, a second capping layer is disposed on the first capping layer, and a third capping layer is disposed on the second capping layer.

[0345] The top-emitting organic electroluminescent device of the present invention may include the following layers and their positional relationships: it may include a substrate, a reflective electrode, a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, a hole blocking layer, an electron transport layer, an electron injection layer, a light-transmitting electrode, a first capping layer, a second capping layer, and a third capping layer. If the above layers are present, the reflective electrode is on the substrate, the hole injection layer is on the reflective electrode, the hole transport layer is on the hole injection layer, the electron blocking layer is on the hole transport layer, the light-emitting layer is on the electron blocking layer, the hole blocking layer is on the light-emitting layer, the electron transport layer is on the hole blocking layer, the electron injection layer is on the electron transport layer, the light-transmitting electrode is on the electron injection layer, the first capping layer is on the light-transmitting electrode, the second capping layer is on the first capping layer, and the third capping layer is on the second capping layer.

[0346] As the substrate for the organic electroluminescent device of this invention, any substrate commonly used in organic electroluminescent devices can be used. Examples include transparent substrates, such as glass or transparent plastic substrates; opaque substrates, such as silicon substrates; and flexible PI film substrates. Different substrates have different mechanical strengths, thermal stability, transparency, surface smoothness, and water resistance. Their application varies depending on their properties. In this invention, a transparent glass substrate is preferred, and the thickness of the substrate is not particularly limited.

[0347] A reflective electrode is formed on a substrate, and the reflective electrode and the transparent electrode may be opposite each other. In this invention, the reflective electrode is the anode. When the reflective electrode is the anode, the anode material is preferably a material with a high work function so that holes can be easily injected into the organic functional material layer. Non-limiting examples of anode materials include, but are not limited to, indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO2), zinc oxide (ZnO), magnesium (Mg), aluminum (Al), silver (Ag), aluminum-lithium (Al-Li), calcium (Ca), magnesium-indium (Mg-In), and magnesium-silver (Mg-Ag). The reflective electrode may have a single-layer structure or a multilayer structure including two or more layers. In addition, the thickness of the anode depends on the material used, typically 50-500 nm, preferably 70-300 nm, and more preferably 100-200 nm.

[0348] The hole injection layer, hole transport layer, and electron blocking layer can be disposed between the first electrode and the light-emitting layer.

[0349] The hole injection layer may comprise a host material and a p-type doped material. The host material may be selected from conventional hole transport materials in the prior art, preferably the same organic material as the hole transport layer. The p-type doped material is selected from charge-conducting compounds disclosed in the prior art, and may be selected from compounds disclosed in the following patent documents: WO2011073149A, EP1968131A1, EP2276085A1, EP2213662A1, EP1722602A1, EP2 045848A1, DE102007031220A1, US20100181555A1, US20100102709A1, WO2009003455A1, WO2010094378A1, WO2011120709A1, US20100096600A1, DE102012209523A1, CN101728485A and WO2012095143A1, but not limited to these.

[0350] For example, the compounds shown below:

[0351] P-1, P-2, P-3.

[0352] According to the present invention, P-1 is preferably used as the P-type doped material.

[0353] The thickness of the hole injection layer of the present invention can be 1-100 nm, preferably 2-50 nm and more preferably 5-20 nm.

[0354] The material of the hole transport layer is preferably a material with high hole mobility, which enables holes to be transferred from the anode or hole injection layer to the light-emitting layer.

[0355] Preferably, the hole transport layer material of the present invention may be selected from the following compounds disclosed in the prior art: JP1996048656A, CN1702065A, CN101535256A, CN103108859A, US20120112176A1, JP1989142657A, WO2014034795 A1.

[0356] The thickness of the hole transport layer of the present invention can be 5-200 nm, preferably 10-180 nm, and more preferably 20-150 nm.

[0357] The electron blocking layer requires that its triplet (T1) energy level be higher than that of the host material in the emissive layer, thus blocking energy loss from the emissive layer material. The HOMO energy level of the electron blocking layer material should be between that of the hole transport layer material and the host material of the emissive layer, facilitating hole injection from the positive electrode into the emissive layer. Simultaneously, the electron blocking layer material should possess high hole mobility to promote hole transport and reduce the power consumption of the device. The LUMO energy level of the electron blocking layer material should be higher than that of the host material of the emissive layer, serving as an electron blocker; that is, the electron blocking layer material should have a wide bandgap (Eg). Electron blocking layer materials meeting these conditions can be triarylamine derivatives, fluorene derivatives, spirofluorene derivatives, dibenzofuran derivatives, carbazole derivatives, etc.

[0358] In one embodiment of the present invention, the electron blocking layer material may be selected from the following compounds disclosed in the prior art: CN102046613A, CN105408448A, KR1020160049955A, US20170018710A1, KR1020130106255A, EP2922932A1, CN102224150A.

[0359] According to the present invention, the thickness of the electron blocking layer may be 1-200 nm, preferably 5-150 nm, and more preferably 5-50 nm.

[0360] According to the present invention, the light-emitting layer is located between the electron blocking layer and the hole blocking layer. The material of the light-emitting layer is a material that emits visible light by respectively receiving holes from the hole transport region and electrons from the electron transport region, and combining the received holes and electrons. The light-emitting layer may include a host material and a dopant material. The host material may be classified as a red light host material, a green light host material, a blue light host material, etc., and the dopant material may be classified as a red light dopant material, a green light dopant material, a blue light dopant material, etc. The present invention takes a blue light device as an example, using it as the host material and guest material of the light-emitting layer of the organic electroluminescent device of the present invention. The host material may be one or a combination of two of the following: anthracene derivatives, quinoxaline derivatives, triazine derivatives, xanthone derivatives, diphenyl ketone derivatives, carbazole derivatives, pyridine derivatives, or pyrimidine derivatives. The guest material may be a pyrene derivative, a boron derivative, a quinolone derivative, a spirofluorene derivative, an iridium complex, or a platinum complex.

[0361] The thickness of the light-emitting layer of the present invention can be 5-60 nm, preferably 10-50 nm, and more preferably 20-45 nm.

[0362] A hole blocking layer can be placed above the light-emitting layer. The triplet (T1) energy level of the hole blocking layer material is higher than the T1 energy level of the main material of the light-emitting layer, which can block the energy loss of the light-emitting layer material; the HOMO energy level of the material is lower than the HOMO energy level of the main material of the light-emitting layer, which can block holes. At the same time, the hole blocking layer material is required to have a suitable electron mobility to facilitate electron transport and reduce the power consumption of the device.

[0363] As the hole-blocking layer of the organic electroluminescent device of the present invention, hole-blocking layer materials for organic electroluminescent devices disclosed in the prior art can be used: Compounds disclosed in the prior art can be used as hole-blocking layer materials for organic electroluminescent devices.

[0364] JP2015111679A, KR1020180043220A, CN109564982A, KR1020180065246A.

[0365] The thickness of the hole blocking layer of the present invention can be 2-200 nm, preferably 5-150 nm and more preferably 5-50 nm, but the thickness is not limited to this range.

[0366] An electron transport layer can be disposed above a hole blocking layer. The electron transport layer material is one that readily receives electrons from the cathode and transfers them to the light-emitting layer. Preferably, a material with high electron mobility is used. As the electron transport layer of the organic electroluminescent device of the present invention, compounds disclosed in the prior art can be used as the electron transport layer material for the organic electroluminescent device:

[0367] CN1784388A, CN1625552A, CN107431141A, CN107431141A, KR1020160149041A, CN109564973A, CN10 3827256A, KR101847347B1, KR1020190050658A, CN102574813A, CN107721979A, KR1020100073954A.

[0368] In a preferred embodiment of the invention, the electron transport layer further includes other compounds conventionally used in electron transport layers, such as Alq3, Liq, preferably Liq.

[0369] The thickness of the electron transport layer of the present invention can be 10-80 nm, preferably 20-60 nm, and more preferably 25-45 nm.

[0370] According to the present invention, an electron injection layer may be disposed between the electron transport layer and the cathode. The electron injection layer material is generally preferably a material with a low work function, which facilitates electron injection into the organic functional material layer. Preferably, the electron injection layer material is an N-type metal material. As the electron injection layer material for the organic electroluminescent device of the present invention, the following electron injection layer materials for organic electroluminescent devices disclosed in the prior art can be used: LiF, Cs₂CO₃, CsF₂, Csq, NaF, MgF₂, CaF₂, Al₂O₃, and Yb.

[0371] The thickness of the electron injection layer of the present invention can 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.

[0372] According to the present invention, as described above, a transparent electrode is used as the cathode. The material used to form the cathode can be a material with low work function, such as metals, alloys, conductive compounds, or mixtures thereof. Non-limiting examples of cathode materials may include lithium (Li), ytterbium (Yb), magnesium (Mg), aluminum (Al), calcium (Ca), as well as aluminum-lithium (Al-Li), magnesium-indium (Mg-In), and magnesium-silver (Mg-Ag). The thickness of the cathode depends on the material used, typically 5-100 nm, preferably 7-50 nm, and more preferably 10-25 nm.

[0373] This invention application provides a light extraction layer on top of the light-transmitting electrode (i.e., cathode) of the device;

[0374] Organic electroluminescent devices may also include an encapsulation structure. The encapsulation structure may be a protective structure that prevents external 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 or metal can; or a thin film covering the entire surface of the organic layer.

[0375] Methods for fabricating organic electroluminescent devices

[0376] The present invention provides a method for fabricating the aforementioned organic electroluminescent device, comprising sequentially laminating a reflective electrode, an organic light-emitting functional layer, a light-transmitting electrode, a first capping layer, a second capping layer, and a third capping layer on a substrate. The organic light-emitting functional layer is formed by sequentially laminating a hole transport region thin film layer, a light-emitting region thin film layer, and an electron transport region thin film layer on the reflective electrode from bottom to top. The hole transport region thin film layer is formed by sequentially laminating a hole injection layer, a hole transport layer, and an electron blocking layer on the first electrode from bottom to top. The electron transport region thin film layer is formed by sequentially laminating a hole blocking layer, an electron transport layer, an electron injection layer, and a light-transmitting electrode on the light-emitting layer from bottom to top. Furthermore, a first capping layer is laminated on the light-transmitting electrode, a second capping layer is laminated on top of the first capping layer, and a third capping layer is laminated on top of the second capping layer.

[0377] Regarding lamination, methods such as vacuum deposition, vacuum evaporation, spin coating, casting, LB method, inkjet printing, laser printing, or LITI can be used, but are not limited to these. Among them, vacuum evaporation refers to heating the material and depositing it onto the substrate in a vacuum environment.

[0378] In this invention, vacuum evaporation is preferably used to form the various layers, wherein the vapor deposition process can be carried out at a temperature of about 100-500°C for about 10... -8 -10 -2 Vacuum deposition is performed at a vacuum level of approximately 0.01-50 Å / s. The vacuum level is preferably 10 Å. -6 -10 -2 Torr, more preferably 10 -5 -10 -3 Torr. The rate is about 0.05-20 Å / s, more preferably about 0.1-10 Å / s.

[0379] In addition, it should be noted that the materials used to form each layer described in this invention can be used as a single layer by forming a film on their own, or they can be used as a single layer by mixing with other materials to form a film. They can also be a stacked structure between layers that are formed on their own, a stacked structure between layers that are formed by mixing, or a stacked structure between layers that are formed on their own and layers that are formed by mixing.

[0380] The following examples are intended to better explain the present invention, but the scope of the invention is not limited thereto.

[0381] Example

[0382] I. Compound Preparation Examples

[0383] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0384] 1. The preparation of compound C53 is described in reference to patent US5872357A;

[0385] 2. The preparation of compound C75 is described in reference to patent US7193015A1;

[0386] 3. The preparation of compound A74 is described in reference to patent CN115611884A;

[0387] 4. The preparation of compound A15 is described in reference to patent CN110229145A.

[0388] 5. The preparation of compound B37 is described in reference to patent CN117229192A.

[0389] 6. The preparation of compound B39 is described in reference to patent CN117229192A.

[0390] II. Determination of the physical properties of compounds

[0391] Measurement method: The refractive index n was measured by an ellipsometer (JAWoollam Co., USA, model: ALPHA-SE) (tested in an atmospheric environment); the test results are shown in Table 1 below.

[0392] Table 1

[0393]

[0394] Table 2

[0395]

[0396] Table 3

[0397]

[0398] "n@460nm" refers to the refractive index of a material relative to a vacuum for blue light at a wavelength of 460 nm.

[0399] "n@525nm" refers to the refractive index of a material relative to a vacuum for green light at a wavelength of 525 nm.

[0400] "n@620nm" refers to the refractive index of a material relative to a vacuum for red light at a wavelength of 620 nm.

[0401] III. Device Examples

[0402] The following device examples further illustrate the beneficial technical effects of applying the light extraction layer of the present invention to top-emitting organic electroluminescent devices.

[0403] 1. Materials, equipment, and testing methods used in the embodiments.

[0404] Materials sourced from commercial purchases or synthesized independently by referencing existing technical literature.

[0405] The molecular structural formulas of the relevant materials are shown below:

[0406] HT-1 EB-1

[0407] HB-1 ET-1

[0408] (C14) (A111)

[0409] equipment:

[0410] Vacuum Evaporation Equipment: Choshu Sangyo, Japan, 200*200mm Evaporation Equipment

[0411] Test method:

[0412] Measurement of current efficiency, CIEx, CIEy, and perceptible color difference (JNCD):

[0413] Using an IVL (current-voltage-luminance) testing system (Suzhou Fosstar Scientific Instruments Co., Ltd.), and selecting software EILV20060707, the devices in the following device examples and comparative examples were tested. Data such as IVL characteristic curves, efficiency versus current density curves, and color coordinate positions were obtained. Testing must be conducted in a dark environment under a masking device. (At @10mA / cm) 2 The data under the specified conditions shall prevail (i.e., the test current density reaches 10 mA / cm²). 2 (The corresponding performance values ​​at that time).

[0414] Structure and fabrication method of device embodiment 1:

[0415] Structure of Device Example 1: Substrate layer / First electrode 201 (Ag (100 nm)) / Hole injection layer 20210 (HT-1:P-1 = 97:3 mass ratio, thickness 10 nm) / Hole transport layer 20220 (HT-1, thickness 130 nm) / Electron blocking layer 20230 (EB-1, thickness 5 nm) / Light emitting layer 20240 (BH-1:BD-1 = 97:3 mass ratio, thickness 20 nm) / Hole blocking layer 20250 (HB-1, thickness 5 nm) / Electron transport layer 20260 (ET-1:LiQ = 1:1 mass ratio, thickness 30 nm) / Electron injection layer 20270 (LiF, thickness 1... nm) / Transparent electrode 203 (Mg:Ag=1:9 mass ratio, thickness 16nm) / First capping layer 204 (compound C53 of the present invention, thickness 15nm) / Second capping layer 205 (compound A74 of the present invention, thickness 15nm) / Second capping layer 206 (compound B37 of the present invention, thickness 50nm).

[0416] Fabrication method of device embodiment 1: The transparent substrate layer is transparent glass. Ag (100nm) is deposited as the first electrode 201. On the first electrode 201, HT-1 and P-1 with a thickness of 10nm are deposited using a vacuum evaporation apparatus as a hole injection layer 20210, with a mass ratio of HT-1 to P-1 of 97:3. Next, HT-1 with a thickness of 130nm is deposited as a hole transport layer 20220. Subsequently, EB-1 with a thickness of 5nm is deposited as an electron blocking layer 20230. After the above electron blocking materials are deposited, the light-emitting layer 20240 of the organic electroluminescent device is fabricated. Its structure includes BH-1 as the host material and BD-1 as the dopant material, with a doping ratio of 3% by weight. The thickness of the light-emitting layer is 20nm. After the above light-emitting layer 20240, HB-1 is deposited with a thickness of 5nm as a hole blocking layer 20250. On top of the hole-blocking layer 20250, ET-1 and LiQ are further deposited by vacuum evaporation, with an ET-1 to LiQ mass ratio of 1:1. The vacuum-deposited film thickness of this material is 30 nm, and this layer is the electron transport layer 20260. On the electron transport layer 20260, a LiF layer with a thickness of 1 nm is fabricated using a vacuum evaporation apparatus; this layer is the electron injection layer 20270. On the electron injection layer 20270, a Mg:Ag electrode layer with a thickness of 16 nm is fabricated using a vacuum evaporation apparatus, with a Mg to Ag mass ratio of 1:9; this layer is the light-transmitting electrode 203. On the light-transmitting electrode 203, compound C53 of the present invention with a thickness of 15 nm is vacuum-deposited as a first capping layer 204; on the first capping layer 204, compound A74 of the present invention with a thickness of 15 nm is vacuum-deposited as a second capping layer 205; on the second capping layer 205, compound B37 of the present invention with a thickness of 50 nm is vacuum-deposited as a third capping layer 206.

[0417] Device Examples 2 to 8 have similar device structures and fabrication methods to Device Example 1, except that the compounds used in the first, second, and third capping layers are changed, as detailed in Table 4.

[0418] The device structures and fabrication methods of Comparative Examples 1 and 2 are similar to those of Device Example 1, except that the first and second cover layers are not used. The specific cover layer materials and film thicknesses are described in Table 4 below.

[0419] The device structures and fabrication methods of Comparative Examples 3 to 6 are similar to those of Device Example 1, except that a second cover layer is not used. The specific cover layer materials and film thicknesses are described in Table 4 below.

[0420] The device structures and fabrication methods of Comparative Examples 7 to 10 are similar to those of Device Example 1, except that a first cover layer is not used. The specific cover layer material and film thickness are described in Table 4 below.

[0421] The device structure and fabrication method of Comparative Example 1 are similar to those of Device Example 1, except that the compounds used in the first, second, and third capping layers are changed. The specific capping layer materials and film thicknesses are shown in Table 4 below.

[0422] The materials of the first and second capping layers in the device, the current efficiency of the third capping layer device, and the CIEy test data are listed in Table 4.

[0423] Table 4

[0424]

[0425] Note: Index = current efficiency / CIEy, and it is only applied to blue light devices. The efficiency of blue light devices is generally not determined by current efficiency, but by Index (industry standard).

[0426] As shown in Table 4, in top-emitting organic electroluminescent devices, the light extraction layer structure of the present invention has a significant improvement in device efficiency compared with existing structures (device comparison examples 1-2 are single high-refractive-index structures, device comparison examples 3-10 are high-low refractive index dual-layer structures, and device comparison example 11 is a low-high-low three-layer structure).

Claims

1. A light extraction layer, comprising, in sequence along the light extraction direction: First covering layer; A second cover layer is placed on top of the first cover layer; A third cover layer, which is located on top of the second cover layer; The feature is that the first covering layer contains a phosphazene compound or a siloxane compound; The second coating layer contains a fluorinated organic compound; The refractive index of the material in the first capping layer is less than that of the material in the second capping layer, and the refractive index of the material in the second capping layer is less than that of the material in the third capping layer.

2. The light extraction layer according to claim 1, characterized in that, The refractive index of the material in the third capping layer is n3@460nm≥1.80, preferably n3@460nm≥1.90, preferably n3@460nm≥2.00, preferably n3@460nm≥2.10, preferably n3@460nm≥2.15, and preferably n3@460nm≥2.

20. The refractive index of the material in the second capping layer is 1.40≤n2@460nm≤1.70, preferably 1.40≤n2@460nm≤1.65, preferably 1.40≤n2@460nm≤1.60, preferably 1.40≤n2@460nm≤1.55, preferably 1.40≤n2@460nm≤1.50, and preferably 1.40≤n2@460nm≤1.

45. The refractive index of the material in the first capping layer is 1.10≤n1@460nm≤1.40, preferably 1.20≤n1@460nm≤1.4, preferably 1.25≤n1@460nm≤1.40, and preferably 1.30≤n1@460nm≤1.

40.

3. The light extraction layer according to claim 1, characterized in that, The difference in refractive index between the material in the second capping layer and the material in the first capping layer, Δn@460nm, is ≥0.10, preferably Δn@460nm is 0.10-0.50, and more preferably Δn@460nm is 0.15-0.

30.

4. The light extraction layer according to claim 1, characterized in that, The difference in refractive index between the material in the second capping layer and the material in the third capping layer, Δn@460nm, is ≥0.50, preferably Δn@460nm is 0.50-1.20, preferably Δn@460nm is 0.50-1.00, preferably Δn@460nm is 0.55-0.95, preferably Δn@460nm is 0.60-0.90, and preferably Δn@460nm is 0.65-0.

86.

5. The light extraction layer according to claim 1, characterized in that, The core framework of the phosphazene compound is a cyclophosphazene structure, and the core framework of the siloxane compound is a silsesquioxane structure. Preferably, the phosphazene compound and the siloxane compound contain fluorinated branches; Preferably, the fluorinated branch is a fluoroalkyl group substituted or unsubstituted, a fluoroalkoxy group substituted or unsubstituted, a fluoroalkylsilyloxy group substituted or unsubstituted, a fluorocycloalkyl group substituted or unsubstituted, a fluoroaryl group substituted or unsubstituted, or an aryl group substituted or unsubstituted. The substituents are fluorine atoms, -CH3, -C(CH3), -C(CF3), -CF3, -CH2F2, -CHF2, -CH2CH3, -CH2CH2CH3, -O-CH3, -O-CH2CH3, -O-(CH2)2CH3, -O-(CH2)3CH3, -O-(CH2)4CH3, -O-(CH2)5CH3, -O-CF3, -O-CH2CF3, -O-(CH2)2CF3, -O-(CH2)3CF3, -O-(CH2)4CF3, -O-(CH2)5CF3, -O-CF2CF3, -O-(CF2)2CF3, -O-(CF2)3CF3, -O-(CF2)4CF3, -O-(CF2)5CF3, -CF2CF3, -CF2CF2CF3, -CF2CF2CF2CF3; Preferably, the fluoroalkyl group substituted or unsubstituted comprises at least one of CF, CF2, CF3 or CF2H units.

6. The light extraction layer according to claim 1, characterized in that, The material in the third covering layer can be selected from the structures shown in general formulas (A-1), (A-2), (A-3), (A-4), or (A-5): (A-1) (A-2) (A-3) (A-4) (A-5) In general formulas (A-1), (A-2), (A-3), (A-4), and (A-5), L 30 L 31 L 32 L 33 Each can be represented independently as a single bond, a C6-C bond substituted with a substituent, or an unsubstituted bond. 30 arylene, C2-C substituted or unsubstituted 30 heteroaryl; L 34 Represented as C6-C with or without substituents. 30 arylene, C2-C substituted or unsubstituted 30 heteroaryl; M represents the C6-C column, which may or may not be substituted with a substituent. 30 Aryl, substituted or unsubstituted C2-C 30 Mixed aromatics; X is represented independently as O, S, or NR. 30 ; Each occurrence of Z, whether identical or different, is independently represented as CR. 31 ; Each occurrence of Y, whether identical or different, is independently represented by N or CR. 32 ; The R 30 Represented as C6-C with or without substituents. 30 Aryl, substituted or unsubstituted C2-C 30 Mixed aromatics; The R 31 R 32 Ar 31 Ar 32 Ar 33 Each can be represented independently as a hydrogen atom, a C1-C atom substituted with a substituent, or an unsubstituted atom. 20 Alkyl groups, substituted or unsubstituted C2-C 20 Alkenyl, C6-C substituted or unsubstituted 30 Aryl, substituted or unsubstituted C2-C 30 Heteroaryl, arylamine group substituted or unsubstituted; M represents the C6-C column, which may or may not be substituted with a substituent. 30 Aryl, substituted or unsubstituted C2-C 30 Mixed aromatics; The substituents are selected from C6-C6. 30 Aryl, C2-C 30 One or more of the heteroaryl groups.

7. The light extraction layer according to claim 1, characterized in that, The material in the second covering layer is selected from the structure shown in general formula (B-1) or (B-2): General formula (B-1) In general formula (B-1), R represents F, , , , , or ; Ar1 represents C1-C, substituted or unsubstituted. 20 Alkyl groups, substituted or unsubstituted C1-C 20 Alkoxy, substituted or unsubstituted aromatic amino groups, substituted or unsubstituted C6-C 30 Aryl, substituted or unsubstituted C2-C 30 heteroaryl, substituted or unsubstituted C6-C 30 Silyl aryl, C2-C substituted or unsubstituted 30 Silyl aryl, C6-C substituted or unsubstituted 30 aryl ether group, C2-C group substituted or unsubstituted 30 heteroaryl ethers; Each occurrence of n, whether the same or different, is represented independently as 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30; Each occurrence of y, whether the same or different, is independently represented as 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13; Each occurrence of j, whether the same or different, is independently represented as 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10; Each occurrence of Y2 or Y3 being the same or different is independently represented as CR. 21 Or N; The R 21 Each instance of the same or different element is represented by a hydrogen atom, deuterium atom, halogen atom, cyano group, or C1-C atoms that are substituted or unsubstituted. 20 Alkyl groups, substituted or unsubstituted C1-C 20 Alkoxy groups, C1- groups substituted or unsubstituted 20 Silyl, C1-C substituted or unsubstituted 20 Silyloxy group, substituted or unsubstituted C6-C 30 Aryl, substituted or unsubstituted C2-C 30 Mixed aromatics; The substituent is selected from deuterium, halogen, cyano, trifluoromethyl, trifluoromethoxy, halogen-substituted or unsubstituted C1-C. 20 Alkyl, halogen-substituted or unsubstituted C1-C 20 alkoxy, halogen-substituted or unsubstituted C1-C 20 Silyl, halogen-substituted or unsubstituted C1-C 20 Silyloxy group, C6-C 30 arylamine, C2-C 30 heteroarylamine, C6-C 30 Silylaryl, C2-C 30 Silyl aryl, C6-C 30 Aryl, C2-C 30 One or more of the heteroaryl groups; General formula (B-2) In general formula (B-2), La is selected from the following structures: 、 、 Ar2 and Ar3 represent hydrogen atoms, fluorine atoms, trifluoromethyl groups, and C1-C atoms that are substituted or unsubstituted. 20 Alkyl groups, substituted or unsubstituted C6-C 30 Aryl, substituted or unsubstituted C2-C 30 Heteroaryl, arylamine group substituted or unsubstituted, or the structure shown in formula a; Formula a In formula a, L c Represents a single bond, a C6-C bond substituted with a substituent, or an unsubstituted bond. 30 arylene, C2-C substituted or unsubstituted 30 Heteroaryl, C6-C substituted or unsubstituted 30 arylene amino group, or C2-C group substituted or unsubstituted. 30 heteroarylamine; p = 0, 1, 2, 3, 4 or 5; q = 1, 2, 3, 4 or 5; a = 0, 1, 2, 3, 4 or 5; and q + a ≥ 2; k = 1, 2, 3, 4 or 5; b = 0 or 1; Each occurrence of Y2 or Y3 being the same or different is independently represented as CR. 21 Or N; The R 21 Each instance of the same or different element is represented by a hydrogen atom, deuterium atom, halogen atom, cyano group, or C1-C atoms that are substituted or unsubstituted. 20 Alkyl groups, substituted or unsubstituted C1-C 20 Alkoxy groups, C1- groups substituted or unsubstituted 20 Silyl, C1-C substituted or unsubstituted 20 Silyloxy group, substituted or unsubstituted C6-C 30 Aryl, substituted or unsubstituted C2-C 30 Mixed aromatics; The substituent is selected from deuterium, halogen, cyano, trifluoromethyl, trifluoromethoxy, halogen-substituted or unsubstituted C1-C. 20 Alkyl, halogen-substituted or unsubstituted C1-C 20 alkoxy, halogen-substituted or unsubstituted C1-C 20 Silyl, halogen-substituted or unsubstituted C1-C 20 Silyloxy group, C6-C 30 arylamine, C2-C 30 heteroarylamine, C6-C 30 Silylaryl, C2-C 30 Silyl aryl, C6-C 30 Aryl, C2-C 30 One or more of the heteroaryl groups.

8. The light extraction layer according to claim 1, characterized in that, The phosphazene compound is represented by the structure shown in formula (C-1) or formula (C-2): (C-1) (C-2) In equations (C-1) and (C-2), R1-R 14 The same or different atoms are selected from hydrogen atoms, C1-C 20 Straight-chain fluorinated alkyl groups, C1-C 20 Straight-chain fluorinated alkoxy groups, C3-C 20 Branched fluorinated cyclic alkyl groups, C3-C 20 Fluorinated cyclic alkyl groups, C3-C 20 Branched fluorinated cyclic alkoxy groups or C3-C 20 Fluorinated cyclic alkoxy groups; The siloxane is represented by the structure shown in formula (C-3): （C-3） In equation (C-3), R 15 -R 22 The same or different atoms are selected from hydrogen atoms, C1-C 20 Straight-chain fluorinated alkyl groups, C1-C 20 Straight-chain fluorinated alkoxy groups, C3-C 20 Branched fluorinated cyclic alkyl groups, C3-C 20 Fluorinated cyclic alkyl groups, C3-C 20 Branched fluorinated cyclic alkoxy groups or C3-C 20 Fluorinated cyclic alkoxy groups.

9. The light extraction layer according to claim 8, characterized in that, The R1-R 22 The same or different are selected from hydrogen atoms or the structure shown in formula (a-1): Equation (a-1) In equation (a-1), L1 represents a single bond, an oxygen atom, and C1-C. 20 C1-C with alkylene or fluorine atom substitution 20 Alkylene, C1-C 20 C1-C substituted with alkoxide or fluorine atom 20 Alkyloxy; f = 0 or 1; X1, X2, X3, X4, X5, and X6 are each independently represented as a hydrogen atom, a fluorine atom, or a C1-C atom substituted or unsubstituted. 20 Straight-chain alkyl groups, C3-C substituted or unsubstituted 20 Branched alkyl groups, substituted or unsubstituted C3-C 10 Cyclic alkyl, substituted or unsubstituted C1-C 20 Straight-chain alkoxy, substituted or unsubstituted C3-C 20 Branched alkoxy, substituted or unsubstituted C3-C 20 Cyclic alkoxy groups; h = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10; v = 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10; t = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10; The substituents are selected from C1-C atoms, substituted or unsubstituted fluorine atoms. 20 Straight-chain alkyl, fluorine-substituted or unsubstituted C3-C 20 Branched alkyl groups.

10. A top-emitting organic electroluminescent device, comprising: substrate; A reflective electrode, wherein the reflective electrode is located on the substrate; An organic functional layer is located above the reflective electrode; A light-transmitting electrode, wherein the light-transmitting electrode is located on the organic functional layer; A light extraction layer, wherein the light extraction layer is located above the light-transmitting electrode; The characteristic feature is that the light extraction layer is the light extraction layer according to any one of claims 1-9.

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