Organic compound, light-emitting device, light-emitting substrate and light-emitting device

Abstract

The present application discloses an organic compound, a light-emitting device, a light-emitting substrate and a light-emitting device. The organic compound includes a first type of organic compound or / and a second type of organic compound; the structural formula of the first type of organic compound is shown in general formula (1), and the structural formula of the second type of organic compound is shown in general formula (5). The first type of organic compound or / and the second type of organic compound are used in the light-emitting device to improve the performance of the light-emitting device.

Description

Technical Field

[0001] The present invention relates to the field of display technology, and in particular to an organic compound, a light-emitting device, a light-emitting substrate and a light-emitting apparatus. Background Art

[0002] Organic Light-Emitting Diode (OLED) is a light-emitting device that uses organic solid-state semiconductors as light-emitting materials. It has broad application prospects due to its advantages such as simple preparation process, low cost, low power consumption, high brightness, and wide operating temperature range. However, current OLED light-emitting devices have the problems of low luminous efficiency and short lifespan. Summary of the invention

[0003] The purpose of the present disclosure is to provide an organic compound, a light-emitting device, a light-emitting substrate and a light-emitting apparatus. The organic compound is used in the light-emitting device to help improve the light-emitting efficiency and service life of the device.

[0004] To achieve the above objectives, the embodiments of the present disclosure provide the following technical solutions:

[0005] In one aspect, an organic compound is provided, comprising: a first type of organic compound and / or a second type of organic compound;

[0006] The structural formula of the first type of organic compound is shown in general formula (1):

[0007]

[0008] Among them, * indicates the chemical bond connection site;

[0009] X is selected from any one of CR2R3, S or O;

[0010] R1 and R2 are independently selected from hydrogen, deuterium or any one of the structures shown in general formula (2), and the number of deuterium in R1 and R2 is greater than 1, and at least one of R1 and R2 is selected from the structure shown in general formula (3);

[0011] a represents the number of R1, a is selected from any one of 1, 2, 3, and 4. When a is greater than 1, any two R1 are the same or different;

[0012] b represents the number of R2, b is selected from any one of 1, 2, 3, and 4, and when b is greater than 1, any two R2 are the same or different;

[0013] Ar1 and Ar2 are the same or different and are independently selected from hydrogen, deuterium, a halogen group, a nitrile group, a nitro group, a hydroxyl group, a carbonyl group, a substituted or unsubstituted silyl group, a substituted or unsubstituted boron group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkylsulfonyl group, a substituted or unsubstituted arylsulfonyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aralkenyl group, a substituted or unsubstituted alkylaryl group, a substituted or unsubstituted any one of the following: a substituted alkylamino group, a substituted or unsubstituted aralkylamino group, a substituted or unsubstituted heteroarylamino group, a substituted or unsubstituted arylamino group, a substituted or unsubstituted arylphosphino group, a substituted or unsubstituted phosphine oxide group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a structure represented by the general formula (3), or a structure represented by the general formula (4); and at least one of Ar1 and Ar2 is selected from the structure represented by the general formula (3) or the structure represented by the general formula (4);

[0014] L1 and L2 are independently selected from any one of a single bond, an arylene group or a heteroarylene group;

[0015] R5, R6 and R7 are independently selected from any one of alkyl or aryl groups, and all hydrogen atoms in R5, R6 and R7 are replaced by deuterium;

[0016] The structural formula of the second type of organic compound is shown in general formula (5):

[0017]

[0018] wherein R3 is selected from any one of hydrogen or deuterium, and the number of deuterium in R3 is greater than 1;

[0019] c represents the number of R3, c is selected from any one of 1, 2, 3, and 4, and when c is greater than 1, any two R3 are the same or different;

[0020] Ring A is selected from any one of an aromatic ring or a heteroaromatic ring having more than two rings, and Ring A contains deuterium;

[0021] The structural formula of Ar3 is shown in general formula (6);

[0022] X1, X2 and X3 are independently selected from C or N, and at least one of X1, X2 and X3 is N;

[0023] L3 is selected from any one of a single bond, an arylene group or a heteroarylene group;

[0024] Ar4 and Ar5 are the same or different and are independently selected from any one of hydrogen, deuterium, a halogen group, a nitrile group, a nitro group, a hydroxyl group, a carbonyl group, a substituted or unsubstituted silyl group, a substituted or unsubstituted boron group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkylsulfonyl group, a substituted or unsubstituted arylsulfonyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aralkenyl group, a substituted or unsubstituted alkylaryl group, a substituted or unsubstituted alkylamino group, a substituted or unsubstituted aralkylamino group, a substituted or unsubstituted heteroarylamine group, a substituted or unsubstituted arylamine group, a substituted or unsubstituted arylphosphino group, a substituted or unsubstituted phosphine oxide group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group.

[0025] On the other hand, a light-emitting device is provided, comprising: a light-emitting layer and a hole transport unit arranged in sequence along a first direction; wherein the hole transport unit comprises the first type of organic compound as described above;

[0026] Or / and, the light-emitting layer includes the second organic compound as described above.

[0027] In yet another aspect, a light-emitting substrate is provided, comprising the light-emitting device as described above.

[0028] In yet another aspect, a light-emitting device is provided, comprising the light-emitting substrate as described above.

[0029] The organic compounds provided by the present disclosure include a first type of organic compound and / or a second type of organic compound; wherein the first type of organic compound adopts a dibenzo structure, which can improve the hole mobility and improve the performance of the light-emitting device without affecting the energy level; the second type of organic compound has a bipolar transmission property, which can well transmit electrons and holes, is conducive to balancing carriers and improving the performance of the light-emitting device. In addition, deuterium atoms are used to replace hydrogen atoms in both the first type of organic compound and the second type of organic compound to increase the bond energy, thereby improving the molecular stability and extending the life of the light-emitting device. The first type of organic compound and the second type of organic compound are used as a hole transport material and a host material, respectively. The two materials have matching energy levels, which is conducive to the transmission of holes from the anode to the light-emitting layer and improves the performance of the light-emitting device. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the present disclosure, the following briefly introduces the drawings required to be used in some embodiments of the present disclosure. Obviously, the drawings described below are only drawings of some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can also be obtained based on these drawings. In addition, the drawings described below can be regarded as schematic diagrams, and are not limitations on the actual size of the product involved in the embodiments of the present disclosure, the actual process of the method, the actual timing of the signal, etc.

[0031] Figure 1 A structural diagram of a light emitting device provided according to some embodiments of the present disclosure;

[0032] Figure 2 Another structural diagram of a light emitting device provided according to some embodiments of the present disclosure;

[0033] Figure 3 A structural diagram of a light-emitting substrate provided according to some embodiments of the present disclosure;

[0034] Figure 4 It is a structural diagram of a light-emitting device provided according to some embodiments of the present disclosure. DETAILED DESCRIPTION

[0035] The following will be combined with the accompanying drawings to clearly and completely describe the technical solutions in some embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, rather than all the embodiments. Based on the embodiments provided by the present disclosure, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present disclosure.

[0036] Unless the context requires otherwise, throughout the specification and claims, the term "comprise" and other forms thereof, such as the third person singular form "comprises" and the present participle form "comprising", are to be interpreted as open, inclusive, that is, "including, but not limited to". In the description of the specification, the terms "one embodiment", "some embodiments", "exemplary embodiments", "example", "specific example" or "some examples" and the like are intended to indicate that specific features, structures, materials or characteristics associated with the embodiment or example are included in at least one embodiment or example of the present disclosure. The schematic representation of the above terms does not necessarily refer to the same embodiment or example. In addition, the specific features, structures, materials or characteristics may be included in any one or more embodiments or examples in any appropriate manner.

[0037] In the following, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present disclosure, unless otherwise specified, "plurality" means two or more.

[0038] “At least one of A, B, and C” has the same meaning as “at least one of A, B, or C” and both include the following combinations of A, B, and C: A only, B only, C only, the combination of A and B, the combination of A and C, the combination of B and C, and the combination of A, B, and C.

[0039] “A and / or B” includes the following three combinations: A only, B only, and a combination of A and B.

[0040] It will be understood that when a layer or an element is referred to as being on another layer or substrate, it can be directly on the other layer or substrate, or intervening layers may be present between the layer or element and the other layer or substrate.

[0041] Exemplary embodiments are described herein with reference to cross-sectional views and / or plan views that are idealized exemplary drawings. In the drawings, the thickness of layers and regions are exaggerated for clarity. Therefore, variations in shape relative to the drawings due to, for example, manufacturing techniques and / or tolerances are contemplated. Therefore, exemplary embodiments should not be interpreted as being limited to the shapes of the regions shown herein, but rather include deviations in shape due to, for example, manufacturing.

[0042] With the continuous advancement of OLED technology, OLED devices have gradually developed into multi-layer thin-film devices with multiple functional layers. People are paying more attention to the research on high-efficiency organic materials and device performance that affect OLED. An organic electroluminescent device with good efficiency and long life is usually the result of an optimized combination of various organic materials. This provides great opportunities and challenges for the design and development of functional materials and device structures of various structures.

[0043] Based on this, the present disclosure provides an organic compound, including a first type of organic compound and / or a second type of organic compound;

[0044] The structural formula of the first type of organic compound is shown in general formula (1):

[0045]

[0046] Among them, * indicates the chemical bond connection site;

[0047] X is selected from any one of CR2R3, S or O;

[0048] R1 and R2 are independently selected from hydrogen, deuterium or any one of the structures shown in general formula (2), and the number of deuterium in R1 and R2 is greater than 1, and at least one of R1 and R2 is selected from the structure shown in general formula (3);

[0049] a represents the number of R1, a is selected from any one of 1, 2, 3, and 4. When a is greater than 1, any two R1 are the same or different;

[0050] b represents the number of R2, b is selected from any one of 1, 2, 3, and 4, and when b is greater than 1, any two R2 are the same or different;

[0051] Ar1 and Ar2 are the same or different and are independently selected from hydrogen, deuterium, a halogen group, a nitrile group, a nitro group, a hydroxyl group, a carbonyl group, a substituted or unsubstituted silyl group, a substituted or unsubstituted boron group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkylsulfonyl group, a substituted or unsubstituted arylsulfonyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aralkenyl group, a substituted or unsubstituted alkylaryl group, a substituted or unsubstituted any one of the following: a substituted alkylamino group, a substituted or unsubstituted aralkylamino group, a substituted or unsubstituted heteroarylamino group, a substituted or unsubstituted arylamino group, a substituted or unsubstituted arylphosphino group, a substituted or unsubstituted phosphine oxide group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a structure represented by the general formula (3), or a structure represented by the general formula (4); and at least one of Ar1 and Ar2 is selected from the structure represented by the general formula (3) or the structure represented by the general formula (4);

[0052] L1 and L2 are independently selected from any one of a single bond, an arylene group or a heteroarylene group;

[0053] R5, R6 and R7 are independently selected from any one of alkyl or aryl groups, and all hydrogen atoms in R5, R6 and R7 are replaced by deuterium;

[0054] The structural formula of the second type of organic compound is shown in general formula (5):

[0055]

[0056] wherein R3 is selected from any one of hydrogen or deuterium, and the number of deuterium in R3 is greater than 1;

[0057] c represents the number of R3, c is selected from any one of 1, 2, 3, and 4, and when c is greater than 1, any two R3 are the same or different;

[0058] Ring A is selected from any one of an aromatic ring or a heteroaromatic ring having more than two rings, and Ring A contains deuterium;

[0059] The structural formula of Ar3 is shown in general formula (6);

[0060] X1, X2 and X3 are independently selected from C or N, and at least one of X1, X2 and X3 is N;

[0061] L3 is selected from any one of a single bond, an arylene group or a heteroarylene group;

[0062] Ar4 and Ar5 are the same or different and are independently selected from any one of hydrogen, deuterium, a halogen group, a nitrile group, a nitro group, a hydroxyl group, a carbonyl group, a substituted or unsubstituted silyl group, a substituted or unsubstituted boron group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkylsulfonyl group, a substituted or unsubstituted arylsulfonyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aralkenyl group, a substituted or unsubstituted alkylaryl group, a substituted or unsubstituted alkylamino group, a substituted or unsubstituted aralkylamino group, a substituted or unsubstituted heteroarylamine group, a substituted or unsubstituted arylamine group, a substituted or unsubstituted arylphosphino group, a substituted or unsubstituted phosphine oxide group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group.

[0063] In the present disclosure, S represents sulfur, O represents oxygen, C represents carbon, and N represents nitrogen.

[0064] In the present disclosure, the first type of organic compound is an aromatic amine + dibenzo structure, wherein the dibenzo structure can improve the molecular hole mobility and fine-tune the energy level (HOMO, T1) to meet the requirements of different light-emitting device structures, that is, to improve the performance of the light-emitting device without affecting the energy level. The second type of organic compound has a bipolar transport property, can transmit electrons and holes well, is conducive to balancing carriers, and improves the performance of the light-emitting device.

[0065] Hydrogen (H) atoms are common elements in OLED materials, and the bond energy of XH (X is carbon, nitrogen, etc.) is greatly affected by the chemical environment in which the molecule is located. The CH or NH bonds at some positions have low canon, which will become the starting point for material degradation. In the present disclosure, deuterium atoms are used to replace hydrogen atoms in the first and second organic compounds. Deuterium atoms, as isotopes of hydrogen atoms, have one more neutron, which can inhibit molecular vibration, reduce the XH bond length, increase bond energy, and improve molecular stability, which is beneficial to increasing the life of the light-emitting device.

[0066] In the present disclosure, the halogen group may include fluorine, iodine, bromine, chlorine, and the like.

[0067] In the present disclosure, the alkyl group may include a linear alkyl group or a branched alkyl group, and specific examples include, but are not limited to, methyl, ethyl, propyl, isopropyl, n-butyl, etc. The alkyl group may be substituted or unsubstituted.

[0068] Wherein, when the alkyl group is substituted with one or more substituents, the substituents are independently selected from oxy, halogen group, nitro, cyano, haloalkyl, cycloalkyl, aryl, heteroaryl, heterocyclic group, etc. The understanding of other groups such as silyl, alkylsulfonyl, arylsulfonyl, alkenyl, aralkyl, aralkenyl, alkylaryl, alkylamino, aralkylamino, heteroarylamine, arylamine, arylphosphino, phosphine oxide, aryl, heterocyclic group and other substituents can be understood as described above and will not be repeated here.

[0069] In the present disclosure, an alkenyl group is a hydrocarbon group formed by removing one or more hydrogen atoms from an olefin molecule, and specific examples include but are not limited to vinyl, phenylvinyl, and the like.

[0070] In the present disclosure, aryl refers to an optional functional group or substituent derived from an aromatic carbocyclic ring. The aryl can be a monocyclic aryl (e.g., phenyl) or a polycyclic aryl. In other words, the aryl can be a monocyclic aryl, a condensed ring aryl, two or more monocyclic aryl groups connected by carbon-carbon bond conjugation, a monocyclic aryl and a condensed ring aryl connected by carbon-carbon bond conjugation, and two or more condensed ring aryl groups connected by carbon-carbon bond conjugation. That is, unless otherwise specified, two or more aromatic groups connected by carbon-carbon bond conjugation can also be regarded as aryl of the present disclosure. Among them, condensed ring aryl can include, for example, a bicyclic condensed aryl (e.g., naphthyl), a tricyclic condensed aryl (e.g., phenanthrenyl, fluorenyl, anthracenyl), etc. The aryl does not contain heteroatoms such as B (boron), N (nitrogen), O (oxygen), S (sulfur), P (phosphorus), Se (selenium), and Si (silicon). For example, in the present disclosure, biphenyl, terphenyl, etc. are aryl. Examples of the aryl group may include, but are not limited to, phenyl, naphthyl, fluorenyl, anthracenyl, phenanthrenyl, biphenyl, terphenyl, quaterphenyl, pentphenyl, and the like.

[0071] In the present disclosure, the arylene group refers to a divalent group formed by further losing a hydrogen atom from an aryl group.

[0072] In the present disclosure, when no specific definition is otherwise provided, "hetero" means including at least one heteroatom such as N, O, S, etc. in one functional group and the remaining atoms are carbon and hydrogen.

[0073] Exemplary structures of the first type of compounds represented by the general formula (1) are described below.

[0074] In some embodiments, the structural formula of the first type of organic compound is as shown in general formula (1), and the structure shown in general formula (1) is selected from any one of the following structural formulas 1-1 to 1-24, wherein * represents a chemical bond connection site for connecting the structural position shown in general formula (2);

[0075]

[0076]

[0077] It should be noted that 1-x in the above structural formula is a synonym for each structural formula and is not a part of the structural formula structure, where x is a positive integer.

[0078] In the present disclosure, in the structure represented by the general formula (1), C is carbon, D is deuterium, and Ph-d5 means that all five hydrogen atoms on the benzene ring are replaced by deuterium atoms.

[0079] In the present disclosure, the first type of compound is selected from any one of structures 1-1 to 1-16 shown in the general formula (1). The first type of organic compound adopts a dibenzo structure, which can improve the molecular hole mobility, facilitate the transfer of holes from the anode to the light-emitting layer, and fine-tune the energy level (HOMO, T1) to meet the requirements of different device structures. In addition, deuterium atoms are used to replace hydrogen atoms in the first type of compound. Deuterium atoms are isotopes of hydrogen atoms. They have one more neutron, which can inhibit molecular vibration, reduce bond length, increase bond energy, and improve molecular stability, which is conducive to extending the life of the light-emitting device.

[0080] In some embodiments, the structure represented by the general formula (2) is selected from any one of the following structural formulas 2-1 to 2-40, wherein * represents a chemical bond connection site for connecting the structure position represented by the general formula (1);

[0081]

[0082]

[0083]

[0084] It should be noted that 2-x in the above structural formula is a synonym for each structural formula and is not a part of the structural formula structure, where x is a positive integer.

[0085] In the present disclosure, the first type of organic compound includes any one of structures 2-1 to 2-40 shown in general formula (2). The first type of organic compound uses deuterium atoms to replace hydrogen atoms, which shortens the bond length of the CH bond, increases the bond energy, improves the stability of the molecule, and is beneficial to improving the life of the light-emitting device.

[0086] In some embodiments, the structural formula of the second type of organic compound is shown in general formula (5), and the structure shown in general formula (5) is selected from any one of the following structural formulas 3-1 to 3-8:

[0087]

[0088] It should be noted that 3-x in the above structural formula is a synonym for each structural formula and is not a part of the structural formula structure, where x is a positive integer.

[0089] In the present disclosure, the structural formula of the second type of organic compound is shown in the general formula (5), and the second type of organic compound is selected from any one of the structures 3-1 to 3-8 shown in the general formula (5). The second type of organic compound has bipolar transport properties, can well transport electrons and holes, is beneficial to balance carriers, and improves the performance of light-emitting devices. In the second type of organic compounds, deuterium atoms are used to replace hydrogen atoms, which shortens the bond length of the CH bond, increases the bond energy, improves the stability of the molecule, and is beneficial to prolonging the life of the light-emitting device. The chemical properties at the 3 and 6 positions of carbazole are active and prone to chemical reactions, which is one of the starting points for material degradation. In the present disclosure, the 3 and 6 positions on the carbazole in the second type of organic compounds are all replaced by deuterium atoms. Hydrogen atoms, such as structural formulas 3-1 to 3-8, increase the bond energy and improve the molecular stability.

[0090] In some embodiments, the structure represented by general formula (6) is selected from any one of the following structural formulas 4-1 to 4-14, wherein * represents a chemical bond connection site for connecting to the Ar3 position in the structure represented by general formula (5);

[0091]

[0092]

[0093] It should be noted that 4-x in the above structural formula is a synonym for each structural formula and is not a part of the structural formula structure, where x is a positive integer.

[0094] In the present disclosure, the second type of organic compound has bipolar transport properties, can transmit electrons and holes well, is beneficial to balance carriers, and improves the performance of light-emitting devices.

[0095] In some embodiments, the first type of organic compound is a hole transport material for transporting holes;

[0096] Or / and, the second organic compound is a host material for transporting carriers.

[0097] In the present disclosure, the first type of organic compound has good hole transport properties and can be used as a hole transport material to transport holes, which helps to transfer holes from the anode to the light-emitting layer. The second type of organic compound has a bipolar transport property and can transport both holes and electrons, which is beneficial to balancing carriers. Therefore, the second type of organic compound can be used as a host material to transport carriers.

[0098] The first type of organic compound and the second type of organic compound are used as hole transport materials and host materials respectively. The two materials have matching energy levels, which are conducive to the transmission of holes from the anode to the light-emitting layer, improve the efficiency of the light-emitting device, and improve the performance of the light-emitting device. Deuterium atoms are used to replace hydrogen atoms in the first type of organic compound and the second type of organic compound to increase the bond energy, thereby improving the stability of the hole transport material and the host material.

[0099] In some embodiments, the first type of organic compound is used as a hole transport material in a hole transport unit;

[0100] Or / and, the second organic compound is used as a host material in the light-emitting layer.

[0101] In the present disclosure, the first type of organic compound has good hole transport properties. Using the first type of organic compound in a hole transport unit can improve the luminescence efficiency of the light-emitting device; and using deuterium atoms instead of hydrogen atoms in the first type of organic compound can improve the stability of the hole transport material and extend the life of the light-emitting device.

[0102] The second type of organic compound has bipolar transmission efficiency and is used as a main material in the light-emitting layer to improve the performance of the light-emitting device; and the second type of organic compound uses deuterium atoms instead of hydrogen atoms to improve the stability of the main material and extend the life of the light-emitting device.

[0103] In some preferred embodiments, the first type of organic compound is used as a hole transport material in a hole transport layer and / or an electron blocking layer in a hole transport unit;

[0104] Or / and, the second organic compound is used as an N-type host material in the light-emitting layer.

[0105] In the present disclosure, the first type of organic compound can be used alone in a light-emitting device to improve the efficiency and life of the light-emitting device. For example, the first type of organic compound is used in a hole transport layer or / and an electron blocking layer of a hole transport unit.

[0106] The second type of organic compound can be used alone in a light emitting device to improve the efficiency and life of the light emitting device. For example, the second type of organic compound is used in the light emitting layer of the light emitting device.

[0107] The first type of organic compound and the second type of organic compound can be used in combination in a light-emitting device to further improve the performance of the light-emitting device. For example, the first type of organic compound is used in a hole transport layer, and the second type of organic compound is used in a light-emitting layer; for another example, the first type of organic compound is used in an electron blocking layer, and the second type of organic compound is used in a light-emitting layer.

[0108] In the present disclosure, the host material in the light-emitting layer can be divided into N-type host material and P-type host material, wherein the N-type host material refers to a material with excess electrons on the PN junction and mainly conducts electricity with electrons; the P-type host material refers to a material lacking electrons on the PN junction and mainly conducts electricity with holes. In the present application, the second type of organic compound can be used as an N-type host material for the light-emitting layer, which is beneficial to balance the carriers and improve the performance of the light-emitting device.

[0109] On the other hand, reference Figure 1 , a light-emitting device 10 is provided, comprising: a light-emitting layer 15 and a hole transport unit arranged in sequence along a first direction; wherein the hole transport unit comprises the first type of organic compound in any of the above embodiments;

[0110] Or / and, the light-emitting layer 15 includes the second organic compound in any of the above embodiments.

[0111] In the present disclosure, the first direction is parallel to the direction of light emitted by the light emitting device 10. The first organic compound and / or the second organic compound are used in the light emitting device 10 to improve the performance of the light emitting device 10 and extend the life of the light emitting device 10.

[0112] In some embodiments, reference Figure 1 and Figure 2 The hole transport unit includes a hole injection layer 12, a hole transport layer 13 and an electron blocking layer 14; the hole injection layer 12, the hole transport layer 13, the electron blocking layer 14 and the light-emitting layer 15 are arranged in sequence along the first direction; the hole transport layer 13 and / or the electron blocking layer 14 include the first type of organic compound in any of the above embodiments.

[0113] In the present disclosure, the hole transport unit includes at least two layers. For example, the hole transport unit includes a hole injection layer 12 (HIL), a hole transport layer 13 (HTL) and an electron blocking layer 14 (EBL) arranged in sequence.

[0114] Hole injection layer 12 (HIL): Inorganic oxides may be used, including but not limited to molybdenum oxide, titanium oxide, vanadium oxide, rhenium oxide, ruthenium oxide, chromium oxide, zirconium oxide, hafnium oxide, tantalum oxide, silver oxide, tungsten oxide, manganese oxide, etc.; it may also be a dopant of a strong electron-withdrawing system, including but not limited to F4TCNQ, HATCN, PPDN, etc.; and the hole transport material may also be P-type doped to form the hole injection layer 12 by co-evaporation.

[0115] Among them, the structural formulas of F4TCNQ, HATCN and PPDN are as follows:

[0116]

[0117] Hole transport layer 13 (HTL): using materials with good hole transport properties, which can be aromatic amine or carbazole materials, including but not limited to NPB, TPD, BAFLP, DFLDPBi, TCTA, TAPC, m-MTDATA, etc.; the hole transport layer 13 can also use the first type of organic compound described in any of the above embodiments. Among them, the structural formulas of NPB, TCTA, and TAPC are as follows:

[0118]

[0119] In some embodiments, reference Figure 2 There are multiple electron blocking layers 14, and the multiple electron blocking layers 14 are arranged along a second direction, and the second direction is perpendicular to the first direction; at least one of the multiple electron blocking layers 14 includes the first type of organic compound.

[0120] In this disclosure, reference Figure 2 , the multiple electron blocking layers 14 are respectively a first electron blocking layer 14a, a second electron blocking layer 14b and a third electron blocking layer 14c. One of the first electron blocking layer 14a, the second electron blocking layer 14b and the third electron blocking layer 14c is a GEBL, another is a BEBL, and the last is a REBL. The number of electron blocking layers can be 1, 2 or 3. For example, when it is 3, the first electron blocking layer 14a, the second electron blocking layer 14b and the third electron blocking layer 14c are arranged along the second direction, and the second direction is perpendicular to the direction of light emitted by the light emitting device 10, that is, the first direction is perpendicular to the second direction.

[0121] In the present disclosure, GEBL, BEBL, and REBL may use aromatic amine or carbazole materials, including but not limited to CBP, PCzPA, etc.; or GEBL, BEBL, and REBL may use the first organic compound in any of the above embodiments; or BEBL, REBL, and GEBL may use the following structures:

[0122]

[0123] Among them, B EBL is an exemplary structure of BEBL, R EBL is an exemplary structure of REBL, G EBL This is an exemplary structure of GEBL.

[0124] In some embodiments, reference Figure 2 There are multiple light-emitting layers 15, and the multiple light-emitting layers 15 are arranged along a second direction, and the second direction is perpendicular to the first direction; at least one of the multiple light-emitting layers 15 includes the second type of organic compound.

[0125] In this disclosure, reference Figure 2 , one of the first light-emitting layer 15a, the second light-emitting layer 15b and the third light-emitting layer 15c is a red light-emitting layer, another is a green light-emitting layer, and the last is a blue light-emitting layer. The number of the light-emitting layers 15 can be 1, 2 or 3. For example, when there are 3, the first light-emitting layer 15a, the second light-emitting layer 15b and the third light-emitting layer 15c are arranged along the second direction, and the second direction is perpendicular to the direction of light emitted by the light-emitting device 10, that is, the first direction is perpendicular to the second direction.

[0126] Exemplarily, when the first light-emitting layer 15a is configured as a red light-emitting layer, the first electron blocking layer 14a is configured as a REBL; the second light-emitting layer 15b is configured as a blue light-emitting layer, the second electron blocking layer 14b is configured as a BEBL; the third light-emitting layer 15c is configured as a green light-emitting layer, and the third electron blocking layer 14c is configured as a GEBL. The first electron blocking layer 14a and the first light-emitting layer 15a are arranged correspondingly along the first direction, the second light-emitting layer 15b and the second electron blocking layer 14b are arranged correspondingly along the first direction, and the third light-emitting layer 15c and the third electron blocking layer 14c are arranged correspondingly along the first direction.

[0127] In the present disclosure, the number of the electron blocking layer 14 is equal to the number of the light-emitting layer 15. For example, if the electron blocking layer 14 includes a first electron blocking layer 14a, the light-emitting layer 15 includes a first light-emitting layer 15a corresponding to the first electron blocking layer 14a; for another example, if the electron blocking layer 14 includes a first electron blocking layer 14a and a second electron blocking layer 14b, the light-emitting layer 15 includes a first light-emitting layer 15a and a second light-emitting layer 15b.

[0128] In the present disclosure, at least one of the first light-emitting layer 15a, the second light-emitting layer 15b and the third light-emitting layer 15c includes the second type of organic compound as described in any of the above embodiments. The second type of organic compound has bipolar transport properties, can transmit electrons and holes well, is beneficial to balance carriers, and improves device performance. Using the second type of organic compound for the light-emitting layer 15 can improve the stability of the light-emitting layer material, thereby extending the life of the light-emitting device 10.

[0129] In the present disclosure, the red light-emitting layer, the green light-emitting layer and the blue light-emitting layer all use a host material, a dopant and a guest material. The host material can be divided into a phosphorescent host material and a fluorescent host material, and the corresponding dopant can be divided into a phosphorescent dopant and a fluorescent dopant. For example, if the red light-emitting layer uses a red phosphorescent host material and a red phosphorescent dopant, it can also use a red fluorescent host material and a red fluorescent dopant; the green light-emitting layer uses a green phosphorescent host material and a green phosphorescent dopant, it can also use a green fluorescent host material and a green fluorescent dopant; the blue light-emitting layer uses a blue phosphorescent host material and a blue phosphorescent dopant, it can also use a blue fluorescent host material and a blue fluorescent dopant. Among them, each host material (such as a red phosphorescent host material or a green fluorescent host material) can contain one material, or it can contain a mixed material of more than two materials.

[0130] For example, the host material (RH) of the red light-emitting layer can be selected from DCM series materials, such as DCM, DCJTB, DCJTI, DCzDBT, etc.; the guest material (RD) of the red light-emitting layer can be selected from metal complexes, such as Ir(piq)2(acac), PtOEP, Ir(btp)2(acac), etc. For example, if the host material (RH) of the red light-emitting layer is DCzDBT, and the guest material (RD) of the red light-emitting layer is Ir(piq)2(acac), the structural formulas of DCzDBT and Ir(piq)2(acac) are as follows:

[0131]

[0132] For example, the host material (GH) of the green light-emitting layer can be selected from coumarin dyes, quinacridone copper derivatives, polycyclic aromatic hydrocarbons, diamine anthracene derivatives, carbazole derivatives, such as DMQA, BA-NPB, Alq3, CBP, etc.; the guest material (GD) of the green light-emitting layer can be a metal complex, such as Ir(ppy)3, Ir(ppy)2(acac), etc. For example, the host material (GH) of the green light-emitting layer is CBP, and the guest material (GD) of the green light-emitting layer is Ir(ppy)3, and the structural formulas of CBP and Ir(ppy)3 are as follows:

[0133]

[0134] For example, the host material (BH) of the blue light-emitting layer can be selected from anthracene derivatives ADN, MADN, etc.; the guest material (BD) of the blue light-emitting layer can be selected from pyrene derivatives, fluorene derivatives, perylene derivatives, styrylamine derivatives, metal complexes, etc., such as TBPe, BDAVBi, DPAVBi, FIrpic, etc. For example, the host material (BH) of the blue light-emitting layer is ADN, and the guest material (BD) of the blue light-emitting layer is DPAVBi, and the structural formulas of ADN and DPAVBi are as follows:

[0135]

[0136] In some embodiments, each of the light-emitting layers includes an N-type host material and a guest material, wherein the N-type host material includes the second type of organic compound.

[0137] In the present disclosure, the first light-emitting layer 15a, the second light-emitting layer 15b, and the third light-emitting layer 15c all include N-type host materials and guest materials, wherein the N-type host material of at least one of the first light-emitting layer 15a, the second light-emitting layer 15b, and the third light-emitting layer 15c includes the second type of organic compound in any of the above embodiments.

[0138] In the present disclosure, the second type of organic compound is used as the N-type host material for the light-emitting layer 15, which is beneficial to balancing the carriers and improving the performance of the light-emitting device 10. (For specific effects, please refer to the experimental data in the subsequent Table 1).

[0139] In some embodiments, each of the light-emitting layers 15 further includes a P-type host material, and the P-type host material is selected from GH2, and the structure of GH2 is as follows:

[0140]

[0141] In the present disclosure, the second type of organic compound is used as the N-type host material and matched with the P-type host material GH2, which can further improve the performance of the light emitting device 10. (For specific effects, please refer to the test data in the subsequent Table 1).

[0142] It should be noted that in the present disclosure, the N-type host material and the corresponding P-type host material may also adopt the following structure, such as the P-type host material (RH P ) and N-type host material (RH N ) has the following structure:

[0143]

[0144] In some embodiments, the first electrode 11 is disposed on a side of the hole transport unit away from the light emitting layer 15 .

[0145] Specifically, refer to Figure 1-2 A first electrode 11 is disposed on a side of the hole injection layer 12 away from the hole transport layer 13. The first electrode 11 may be an anode, and the first electrode 11 is a high work function electrode material, such as transparent oxide ITO, IZO; or a composite electrode formed by ITO / Ag / ITO, Ag / IZO, CNT / ITO, CNT / IZO, GO / ITO, GO / IZO, etc.

[0146] In some embodiments, reference Figure 1-2 An electron transport unit is arranged on a side of the light-emitting layer 15 away from the hole transport unit; the electron transport unit includes a hole blocking layer 16, an electron transport layer 17 and an electron injection layer 18 arranged in sequence along a first direction.

[0147] In the present disclosure, the electron transport unit includes at least two layers of structure, for example, the electron transport unit includes a hole blocking layer 16 (HBL), an electron transport layer 17 (ETL) and an electron injection layer 18 (EIL) sequentially arranged along a first direction. Among them, the hole blocking layer 16, the electron transport layer 17 and the electron injection layer 18 are sequentially arranged along the first direction on the side of the light emitting layer 15 away from the electron blocking layer 14.

[0148] In the hole blocking layer 16 (HBL) and the electron transport layer 17 (ETL): aromatic heterocyclic compounds are used, such as imidazole derivatives such as benzimidazole derivatives, imidazopyridine derivatives, benzimidazolephenanthridine derivatives; oxazine derivatives such as pyrimidine derivatives and triazine derivatives; quinoline derivatives, isoquinoline derivatives, phenanthroline derivatives and other compounds containing nitrogen-containing six-membered ring structures (also including compounds having phosphine oxide-based substituents on the heterocyclic ring). Exemplarily, OXD-7, TAZ, p-EtTAZ, BPhen, BCP, TPBi, LIQ, etc. are used in HBL and ETL. Among them, the structural formulas of BPhen, TPBi, and LIQ are as follows:

[0149]

[0150] Electron injection layer 18 (EIL): uses a material with the ability to transport electrons, which has the effect of injecting electrons from the cathode and has excellent thin film forming ability, such as alkali metals or metals, including but not limited to LiF, Yb, Mg, Ca or their compounds.

[0151] In some embodiments, a second electrode 19 is disposed on a side of the electron transport unit away from the light emitting layer 15 .

[0152] In this disclosure, reference Figure 1-2, a second electrode 19 is provided on the side of the electron injection layer 18 away from the electron transport layer 17. The second electrode 19: can be a cathode, and the cathode material preferably has a material with a low work function so as to easily inject electrons into the organic layer, and has both good light transmittance and conductivity. Specific examples of cathode materials that can be used in the present invention include: metals, metal oxides, and metal alloys, such as aluminum (Al), silver (Ag), gold (Au), magnesium (Mg), calcium (Ca), ytterbium (Yb), indium (In), lithium (Li), potassium (K), sodium (Na), tin (Sn), titanium (Ti), lead (Pb), samarium (Sm), yttrium (Y), indium tin oxide (ITO), magnesium silver alloy (Mg:Ag), ytterbium gold alloy (Yb:Au), Ytterbium silver alloy (Yb:Ag), lithium aluminum alloy (Li:Al), lithium calcium magnesium alloy (Li:Ca:Al), etc.; and laminated materials, such as magnesium / aluminum (Mg / Al), magnesium / silver (Mg / Ag), aluminum / silver (Al / Ag), aluminum / gold (Al / Au), ytterbium / gold (Yb / Au), ytterbium / silver (Yb / Ag), calcium / magnesium (Ca / Mg), calcium / silver (Ca / Ag), barium / silver (Ba / Ag), etc., but not limited to these.

[0153] In some embodiments, reference Figure 1-2 A covering layer 20 is disposed on a side of the second electrode 19 away from the electron transport unit.

[0154] In the present disclosure, the covering layer 20 preferably has a material that can improve the luminous efficiency of the device and increase the service life of the device, which can be a hole-type material, such as aromatic amines, or an electronic type material. Exemplarily, the material of the covering layer 20 can be selected from the following structural formula:

[0155]

[0156] Among the materials of the cover layer 20 , the first one on the left is CPL.

[0157] In the present disclosure, the light emitting device 10 may be an OLED light emitting device 10 , and further, may be an AMOLED (auto-matrix organic light emitting diode) light emitting device 10 .

[0158] On the other hand, reference Figure 3 The present application discloses a light-emitting substrate 100, and the light-emitting substrate 100 includes the light-emitting device 10 as described in any of the above embodiments.

[0159] Specifically, the light emitting device 10 can be manufactured on a light emitting substrate 100 on which the light emitting device 10 described in any of the above embodiments is disposed. The light emitting substrate 100 can be made of a transparent rigid or flexible substrate material, such as glass, polyimide, etc.

[0160] For example, Figure 1 As shown, the light emitting device 10 includes an anode, a hole injection layer 12 (HIL), a hole transport layer 13 (HTL), an electron blocking layer 14 (EBL), a light emitting layer 15 (EML), a hole blocking layer 16 (HBL), an electron transport layer 17 (ETL), an electron injection layer 18 (EIL), a cathode and a capping layer 20 which are sequentially arranged on a light emitting substrate 100 along a first direction. Among them, the thickness of the hole injection layer 12 is 5 to 30 nm, the thickness of the hole transport layer 13 is 100 to 2000 nm, the thickness of the electron blocking layer 14 is 5 to 100 nm, the thickness of the light emitting layer 15 is 20 to 100 nm, the thickness of the hole blocking layer 16 is 5 to 100 nm, the thickness of the electron transport layer 17 is 20 to 100 nm, and the thickness of the electron injection layer 18 is 1 to 10 nm.

[0161] In the present disclosure, the light-emitting principle of the light-emitting device 10 is: holes are injected through the anode, electrons are injected through the cathode, and holes and electrons meet in the light-emitting layer 15 to form excitons, and the excitons excite radiation transition to emit light. According to the different types of electron orbits in the excitons, the excitons can be divided into singlet excitons and triplet excitons, of which singlet excitons account for 25% and triplet excitons account for 75%. The radiation transition luminescence of singlet excitons does not change the spin quantum number of electrons, and can be achieved at room temperature, so the life span of singlet excitons is generally short, at the nanosecond level. The radiation transition luminescence of triplet excitons will change the spin quantum number of electrons, which is spin-forbidden. Phosphorescence emission is generally not observed at room temperature, and needs to be observed at low temperatures, so the life span of triplet excitons is longer, generally at the microsecond level. Traditional fluorescent materials can only use singlet excitons to emit light during the radiation transition process, so the theoretical limit of internal quantum efficiency is 25%. Phosphorescent materials are different. Due to the strong spin coupling of heavy metal atoms, they can simultaneously utilize singlet and triplet excitons to emit light. Therefore, the internal quantum efficiency of OLEDs based on phosphorescent materials can theoretically reach 100%, greatly improving the exciton utilization rate of the device.

[0162] The stability of the device has always been a closely watched issue in the development of phosphorescent OLEDs. First of all, phosphorescent devices have the characteristic of utilizing triplet excitons to emit light, and the longer lifetime of triplet excitons greatly increases the possibility of exciton accumulation, leading to severe triplet-triplet quenching (TTA) and triplet-polaron quenching (TPQ) processes, which are very unfavorable to maintaining the stability of the device. The process of TTA is shown in the formula. Two T1 excitons can form Tn or Sn excitons. These two types of excitons have higher energy and are prone to deterioration of the light-emitting layer material. Therefore, improving the stability of the light-emitting layer material is an effective way to improve the life of the device.

[0163]

[0164] Due to the characteristics of carrier transport in the phosphorescent light-emitting layer, the exciton emission region is generally at the interface between the hole transport layer 13 and the light-emitting layer 15. The molecular stability of the hole transport material is one of the key factors affecting the device life.

[0165] In the present disclosure, the first type of organic compound is used as a hole transport material to improve the stability of the hole transport material, and the second type of organic compound is used as a host material of the light emitting layer to improve the stability of the host material, thereby improving the stability of the light emitting device 10.

[0166] The following describes a method for preparing the light emitting device 10 of the present application.

[0167] Embodiment 0

[0168] A method for preparing a light emitting device 10 comprises the following steps:

[0169] S1: forming a hole transport unit on a substrate with a first electrode 11 .

[0170] Exemplarily, the hole transport unit includes: a hole injection layer 12 , a hole transport layer 13 and an electron blocking layer 14 .

[0171] Exemplarily, the hole transport layer 13 and / or the electron blocking layer 14 include the first organic compound described in any of the above embodiments.

[0172] Exemplarily, before forming the hole transport unit on the substrate with the first electrode 11 , the method further includes step S0 , which is: cleaning the substrate with the first electrode 11 .

[0173] Exemplarily, the first electrode 11 is an anode, and a material of the first electrode 11 is indium tin oxide (ITO).

[0174] Exemplarily, the substrate is a glass substrate.

[0175] Exemplarily, step S0 specifically includes: ultrasonically treating the glass substrate with ITO in a cleaning agent, rinsing in deionized water, ultrasonically degreasing in an acetone-ethanol mixed solvent, and baking in a clean environment until the water is completely removed.

[0176] Exemplarily, step S1 specifically includes the following steps:

[0177] S11: forming a hole injection layer 12 on a side of the first electrode 11 away from the substrate.

[0178] Exemplarily, the material of the hole injection layer 12 (HIL) includes F4TCNQ.

[0179] For example, the substrate with the first electrode 11 is placed in a vacuum chamber and evacuated to 1×10-5 ~1×10 -6 , HIL (such as F4TCNQ) and HTL (such as m-MTDATA) materials are vacuum co-evaporated on the side of the first electrode 11 away from the substrate to form a hole injection layer 12 (HIL), wherein the mass proportion of m-MTDATA in the hole injection layer 12 is 3%.

[0180] Exemplarily, the thickness of the hole injection layer 12 is 10 nm.

[0181] S12 : forming a hole transport layer 13 on a side of the hole injection layer 12 away from the first electrode 11 .

[0182] Exemplarily, the material of the hole transport layer 13 (HTL) is m-MTDATA.

[0183] Exemplarily, a HTL material (such as m-MTDATA) is evaporated on a side of the hole injection layer 12 away from the first electrode 11 to form a hole transport layer 13 (HTL).

[0184] Exemplarily, the thickness of the hole transport layer 13 is 100 nm.

[0185] S13 : forming an electron blocking layer 14 on a side of the hole transport layer 13 away from the hole injection layer 12 .

[0186] Exemplarily, there are multiple electron blocking layers 14, and the multiple electron blocking layers 14 are arranged along a second direction, and the second direction is perpendicular to the first direction; at least one of the multiple electron blocking layers 14 includes the first type of organic compound in any of the above embodiments.

[0187] Exemplarily, the plurality of electron blocking layers 14 are respectively a first electron blocking layer 14 a , a second electron blocking layer 14 b , and a third electron blocking layer 14 c .

[0188] Exemplarily, one of the first electron blocking layer 14a, the second electron blocking layer 14b and the third electron blocking layer 14c is a GEBL, another is a BEBL, and the last is a REBL. For example, the GEBL includes a first organic compound as shown in combination of Structural Formula 1-1 and Structural Formula 2-1.

[0189] Exemplarily, an electron blocking material is evaporated on a side of the hole transport layer 13 away from the hole injection layer 12 to form the electron blocking layer 14 .

[0190] Exemplarily, the thickness of the electron blocking layer 14 is 10 nm.

[0191] S2 : forming a light emitting layer 15 on a side of the hole transport unit away from the first electrode 11 .

[0192] Exemplarily, there are a plurality of light-emitting layers 15 , and the plurality of light-emitting layers 15 are arranged along a second direction, and the second direction is perpendicular to the first direction; and at least one of the plurality of light-emitting layers 15 includes the second type of organic compound.

[0193] Illustratively, the plurality of light emitting layers 15 include a first light emitting layer 15a, a second light emitting layer 15b and a third light emitting layer 15c.

[0194] Exemplarily, one of the first light-emitting layer 15a, the second light-emitting layer 15b and the third light-emitting layer 15c is a red light-emitting layer, another is a green light-emitting layer, and the last one is a blue light-emitting layer.

[0195] Exemplarily, when the first light-emitting layer 15a is configured as a red light-emitting layer, the first electron blocking layer 14a is configured as a REBL; the second light-emitting layer 15b is configured as a blue light-emitting layer, the second electron blocking layer 14b is configured as a BEBL; the third light-emitting layer 15c is configured as a green light-emitting layer, and the third electron blocking layer 14c is configured as a GEBL. The first electron blocking layer 14a and the first light-emitting layer 15a are arranged correspondingly along the first direction, the second light-emitting layer 15b and the second electron blocking layer 14b are arranged correspondingly along the first direction, and the third light-emitting layer 15c and the third electron blocking layer 14c are arranged correspondingly along the first direction.

[0196] Exemplarily, the number of the electron blocking layer 14 is equal to the number of the light-emitting layer 15. For example, if the electron blocking layer 14 includes a first electron blocking layer 14a, the light-emitting layer 15 includes a first light-emitting layer 15a corresponding to the first electron blocking layer 14a; for another example, if the electron blocking layer includes a first electron blocking layer 14a and a second electron blocking layer 14b, the light-emitting layer 15 includes a first light-emitting layer 15a and a second light-emitting layer 15b.

[0197] Exemplarily, each of the light-emitting layers 15 includes an N-type host material and a guest material, wherein the N-type host material includes the second type of organic compound.

[0198] Exemplarily, the first light-emitting layer 15a, the second light-emitting layer 15b, and the third light-emitting layer 15c all include a host material and a guest material. For example, the first light-emitting layer 15a is a red light-emitting layer, the host material RH of the red light-emitting layer is DCzDBT, and the guest material RD of the red light-emitting layer is Ir(piq)2(acac); the structures of DCzDBT and Ir(piq)2(acac) can refer to the above content, which will not be repeated here. For another example, the second light-emitting layer 15b is a blue light-emitting layer, the host material BH of the blue light-emitting layer is ADN, and the guest material BD of the blue light-emitting layer is DPAVBi. The structures of ADN and DPAVBi can refer to the above content, which will not be repeated here.

[0199] For example, the concentration of the host material in the light-emitting layer is 90%-97%, and the concentration of the guest material is 3-10%. For example, in the green light-emitting layer, the concentration of the host material is 90%, and the concentration of the guest material is 10%.

[0200] Exemplarily, a host material and a guest material are evaporated on a side of the electron blocking layer 14 away from the hole transport layer 13 to form the light emitting layer 15 .

[0201] Exemplarily, the first light-emitting layer 15a, the second light-emitting layer 15b, and the third light-emitting layer 15c all include an N-type host material and a guest material, wherein the N-type host material of at least one of the first light-emitting layer 15a, the second light-emitting layer 15b, and the third light-emitting layer 15c includes the second type of organic compound in any of the above embodiments. For example, the N-type host material in the green light-emitting layer includes a second type of organic compound that combines the structure shown in 3-1 and the structure shown in 4-1.

[0202] Exemplarily, each of the light-emitting layers further includes a P-type host material, and the structural formula of the P-type host material is GH2.

[0203] Exemplarily, the thickness of the light emitting layer 15 is 20 nm.

[0204] S3: forming an electron transport unit on a side of the light emitting layer 15 away from the hole transport unit.

[0205] Specifically, the electron transport unit includes a hole blocking layer 16 (HBL), an electron transport layer 17 (ETL), and an electron injection layer 18 (EIL) sequentially disposed along the first direction.

[0206] Exemplarily, step S3 specifically includes the following steps:

[0207] S31 : forming a hole blocking layer 16 on a side of the light emitting layer 15 away from the electron blocking layer 14 .

[0208] Exemplarily, the material of the hole blocking layer 16 is BCP.

[0209] Exemplarily, a HBL material (such as BCP) is evaporated on a side of the light emitting layer 15 away from the electron blocking layer 14 to form the hole blocking layer 16 .

[0210] Exemplarily, the thickness of the hole blocking layer 16 is 5 nm.

[0211] S32 : forming an electron transport layer 17 on the side of the hole blocking layer 16 away from the light emitting layer 15 .

[0212] Exemplarily, the material of the electron transport layer 17 includes LIQ. The structure of LIQ can refer to the above content and will not be described in detail here.

[0213] Exemplarily, HBL (such as BCP) and ETL material (such as LIQ) are co-evaporated on the side of the hole blocking layer 16 away from the light-emitting layer 15, and the two materials are vaporized at the same rate to form the electron transport layer 17. The mass ratio of BCP to LIQ in the electron transport layer 17 is 1:1.

[0214] Exemplarily, the thickness of the electron transport layer 17 is 30 nm.

[0215] S33 : forming an electron injection layer 18 on a side of the electron transport layer 17 away from the hole blocking layer 16 .

[0216] Exemplarily, the material of the electron injection layer 18 is Yb.

[0217] Exemplarily, metal Yb is evaporated on a side of the electron transport layer 17 away from the hole blocking layer 16 to form the electron injection layer 18 .

[0218] Exemplarily, the thickness of the electron injection layer 18 is 1 nm.

[0219] S4: forming a second electrode 19 on a side of the electron transport unit away from the light emitting layer 15 .

[0220] Exemplarily, the second electrode 19 is a cathode.

[0221] Exemplarily, the material of the second electrode 19 includes Mg and Ag.

[0222] Exemplarily, the thickness of the second electrode 19 is 13 nm.

[0223] S5: a covering layer 20 is disposed on a side of the second electrode 19 away from the electron transport unit.

[0224] Exemplarily, the material of the cover layer 20 is CPL. The structure of CPL can refer to the above content, which will not be described here.

[0225] Exemplarily, the thickness of the cover layer 20 is 60 nm.

[0226] It should be noted that the specific materials and specific thicknesses of each layer in the light-emitting device 10 are only exemplary descriptions, and other materials and thickness values ​​may also be used, which will not be listed one by one in this application.

[0227] Example 1

[0228] A method for preparing a light emitting device 10 comprises the following steps:

[0229] S0: The glass substrate with the ITO anode is ultrasonically treated in a cleaning agent, rinsed in deionized water, ultrasonically degreased in an acetone-ethanol mixed solvent, and baked in a clean environment until the water is completely removed.

[0230] S1: forming a hole transport unit on a glass substrate with an ITO anode as follows:

[0231] S11: Place the glass substrate with the ITO anode in a vacuum chamber and evacuate the chamber to a vacuum of 1×10 -5 ~1×10 -6 , HIL (such as HATCN) and HTL (such as NPB) materials are vacuum co-evaporated on the side of the ITO anode away from the glass substrate to form a hole injection layer 12 (HIL) with a thickness of 10 nm, wherein the mass proportion of NPB in the hole injection layer 12 is 2%.

[0232] S12: HTL material (such as NPB) is evaporated on the side of the hole injection layer 12 away from the ITO anode to form a hole transport layer 13 (HTL) with a thickness of 100 nm.

[0233] S13: GEBL material is evaporated on the side of the hole transport layer 13 away from the hole injection layer 12 to form a green electron blocking layer (GEBL) with a thickness of 35 nm. The GEBL material includes the first organic compound shown in the combination of Structural Formula 1-1 and Structural Formula 2-1.

[0234] S2: A green light-emitting layer host material (GH) and a guest material (GD) are evaporated on the side of the green electron blocking layer away from the hole transport layer 13 to form a green light-emitting layer with a thickness of 40 nm. The concentration of GH is 90%, and the concentration of GD is 10%, wherein GH includes an N-type host material, and the N-type host material includes the second organic compound shown in the combination of structural formula 3-1 and structural formula 4-1, and the GD material is Ir(ppy)3.

[0235] S3: forming an electron transport unit on a side of the green light-emitting layer away from the hole transport unit, specifically comprising the following steps:

[0236] S31: vapor-depositing a HBL material (such as BCP) on the side of the green light-emitting layer away from the green electron blocking layer to form a hole blocking layer 16 with a thickness of 5 nm.

[0237] S32: co-evaporating HBL (such as BCP) and ETL material (such as LIQ) on the side of the hole blocking layer 16 away from the green light emitting layer, with the mass ratio of BCP to LIQ being 1:1, to form an electron transport layer 17 with a thickness of 30 nm.

[0238] S33: EIL material (such as Yb) is evaporated on the side of the electron transport layer 17 away from the hole blocking layer 16 to form an electron injection layer 18 with a thickness of 1 nm.

[0239] S4: A cathode material (such as Mg and Ag) is evaporated on the side of the electron injection layer 18 away from the electron transport layer 17 to form a cathode with a thickness of 13 nm.

[0240] S5: vapor-depositing a covering layer 20 material (such as CPL) on the side of the cathode away from the electron injection layer 18 to form a covering layer 20 with a thickness of 60 nm, thereby completing the manufacture of the green light-emitting device 10 .

[0241] Embodiment 2-10

[0242] The specific preparation method of the light emitting device 10 shown in Example 2-10 is the same as that in Example 1, except that the GEBL material used in step S13 and the N-type main material used in step S2 in Example 2-10 are different from those in Example 1, as shown in Table 1.

[0243] Embodiment 11

[0244] The specific preparation method of the light emitting device 10 shown in Example 11 is the same as that in Example 1, except that the host material in step S2 of Example 11 further includes a P-type host material GH2. The structure of GH2 can refer to the above content and will not be repeated here.

[0245] Examples 12-20

[0246] The specific preparation method of the light emitting device 10 shown in Examples 12-20 is the same as that in Example 1, except that the GEBL material used in step S13 and the N-type main material used in step S2 in Examples 12-20 are different from those in Example 1, and the main material in step S2 in Examples 12-20 also includes a P-type main material GH2. The structure of GH2 can refer to the above content and will not be repeated here.

[0247] It should be noted that the difference between Examples 11-20 and the corresponding Examples 1-10 is that the main material in step S2 of Examples 11-20 also includes a P-type main material GH2. For example, the difference between Example 2 and Example 12 is that the main material in step S2 of Example 12 also includes a P-type main material GH2.

[0248] Comparative Example 1

[0249] The specific preparation method of the light emitting device 10 shown in Comparative Example 1 is the same as that of Example 1, except that the GEBL material used in step S13 of Comparative Example 1 and the N-type main body material and P-type main body material used in step S2 are different from those of Example 1. The structure of the GEBL material in Comparative Example 1 is G EBL In Comparative Example 1, the P-type host material of the green light-emitting layer (GH P ) and N-type main material (GH N ) has the following structure:

[0250]

[0251] The voltage, external quantum efficiency (EQE) and device life of the light-emitting device 10 formed using different materials in different embodiments 1-20 and comparative example 1 are compared below. The test conditions are the same. The difference between embodiments 1-20 and comparative example 1 is that the material of the electron blocking layer and the main material of the light-emitting layer are different. The test results are shown in Table 1.

[0252] Among them, the external quantum efficiency refers to the ratio of the number of photons ultimately emitted by the device to the number of injected carriers, reflecting the overall luminous efficiency of the device.

[0253] Table 1

[0254]

[0255]

[0256] It can be seen from Table 1 that, taking the test data in Comparative Example 1 as a reference, setting its voltage, EQE efficiency and lifetime data to 100%, the EQE efficiency and lifetime of the light-emitting device in Examples 1-10 are significantly improved compared with Comparative Example 1, indicating that using the first type of organic compound disclosed in the present invention as a hole transport material for the electron blocking layer of the light-emitting device, and using the second type of organic compound as an N-type main material for the light-emitting layer of the light-emitting device, can significantly improve the luminous efficiency and lifetime of the light-emitting device.

[0257] Compared with the corresponding embodiments 1-10, the EQE efficiency and life of the light-emitting device in embodiments 11-20 are significantly improved, indicating that the second type of organic compound in the present disclosure is used as the N-type main material and matched with the P-type main material GH2 to further balance the carrier transport in the light-emitting layer and extend the device life.

[0258] It should be noted that Examples 1-20 use the first and second organic compounds in green light-emitting devices to improve the performance of the green light-emitting devices. Using the first and second organic compounds in blue light-emitting devices and red light-emitting devices also has the same or similar effects as Examples 1-20.

[0259] Some embodiments of the present disclosure further provide a light-emitting substrate 100, such as Figure 3 As shown, the light-emitting substrate 100 includes the light-emitting device as described in any of the above embodiments.

[0260] The beneficial effects of the above-mentioned light-emitting substrate 100 are the same as the beneficial effects of the light-emitting device provided by the above-mentioned embodiments of the present disclosure, and will not be repeated here.

[0261] Some embodiments of the present disclosure provide a light emitting device 1000, such as Figure 4As shown, the light-emitting device 1000 includes the light-emitting substrate 100 as described above, and of course may also include other components, for example, it may include a circuit for providing an electrical signal to the light-emitting substrate 100 to drive the light-emitting substrate 100 to emit light. The circuit can be called a control circuit and may include a circuit board and / or IC (Integrate Circuit) electrically connected to the light-emitting substrate 100.

[0262] In some embodiments, the light emitting device 1000 may be a lighting device, in which case the light emitting device 1000 is used as a light source to achieve a lighting function. For example, the light emitting device 1000 may be a backlight module in a liquid crystal display device, a lamp for internal or external lighting, or various signal lights.

[0263] In other embodiments, the light-emitting device 1000 may be a display device, in which case the light-emitting substrate 100 is a display substrate for realizing the function of displaying an image (i.e., a picture). The light-emitting device 1000 may include a display or a product including a display. Among them, the display may be a flat panel display (Flat Panel Display, FPD), a micro display, etc. If divided according to whether the user can see the back of the display, the display may be a transparent display or an opaque display. If divided according to whether the display can be bent or curled, the display may be a flexible display or a normal display (which may be called a rigid display).

[0264] Examples of products incorporating a display may include: computer monitors, televisions, billboards, laser printers with display capabilities, telephones, cell phones, personal digital assistants (PDAs), laptop computers, digital cameras, camcorders, viewfinders, vehicles, large-area walls, theater screens or stadium signs, etc.

[0265] The beneficial effects of the above-mentioned light-emitting device 1000 are the same as the beneficial effects of the light-emitting device provided by the above-mentioned embodiments of the present disclosure, and will not be repeated here.

[0266] The above description is only a preferred embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of the invention involved in the present application is not limited to the technical solution formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept. For example, the above features are replaced with (but not limited to) technical features with similar functions disclosed in the present application.

Claims

1. An organic mixture, characterized in that include: The first type of organic compound, the structural formula of the first type of organic compound is shown in general formula (1): Among them, * indicates the chemical bond connection site; R1 and R2 are independently selected from hydrogen, deuterium or any one of the structures shown in the general formula (2), and at least one of R1 and R2 is selected from the structure shown in the general formula (2); a represents the number of R1, a is selected from any one of 1, 2, 3, and 4. When a is greater than 1, any two R1 are the same or different; b represents the number of R2, b is selected from any one of 1, 2, 3, and 4, and when b is greater than 1, any two R2 are the same or different; Ar1 and Ar2 are the same or different and are independently selected from hydrogen, deuterium, a halogen group, a nitrile group, a nitro group, a hydroxyl group, a substituted or unsubstituted silyl group, a substituted or unsubstituted boron group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkylsulfonyl group, a substituted or unsubstituted arylsulfonyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aralkenyl group, a substituted or unsubstituted alkylaryl group, a substituted or unsubstituted alkylamino group, a substituted or unsubstituted aralkylamino group, a substituted or unsubstituted heteroarylamino group, a substituted or unsubstituted arylamino group, a substituted or unsubstituted arylphosphino group, a substituted or unsubstituted phosphine oxide group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, the structure represented by the general formula (3), or the structure represented by the general formula (4); and at least one of Ar1 and Ar2 is selected from the structure represented by the general formula (3); L1 and L2 are independently selected from any one of a single bond, an arylene group or a heteroarylene group; R5, R6 and R7 are independently selected from any one of alkyl or aryl groups, and all hydrogen atoms in R5, R6 and R7 are replaced by deuterium; Wherein, the structure represented by the general formula (1) is selected from any one of the following structural formulas, wherein * represents a chemical bond connection site, which is used to connect the structure position represented by the general formula (2); 。 2. The organic mixture according to claim 1, characterized in that The structure represented by the general formula (2) is selected from any one of the following structural formulas, wherein * represents a chemical bond connection site, which is used to connect the structure position represented by the general formula (1); 。 3. The organic mixture according to claim 1 or 2, characterized in that The organic mixture further comprises a second type of organic compound, the structural formula of the second type of organic compound is shown in general formula (5): wherein R3 is selected from any one of hydrogen and deuterium, and (R3) c contains at least one deuterium; c represents the number of R3, c is selected from any one of 1, 2, 3, and 4, and when c is greater than 1, any two R3 are the same or different; Ring A is selected from any one of an aromatic ring or a heteroaromatic ring having more than two rings, and Ring A contains deuterium; The structural formula of Ar3 is shown in general formula (6); X1, X2 and X3 are independently selected from C or N, and at least one of X1, X2 and X3 is N; L3 is selected from any one of a single bond, an arylene group or a heteroarylene group; Ar4 and Ar5 are the same or different and are independently selected from any one of hydrogen, deuterium, a halogen group, a nitrile group, a nitro group, a hydroxyl group, a carbonyl group, a substituted or unsubstituted silyl group, a substituted or unsubstituted boron group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkylsulfonyl group, a substituted or unsubstituted arylsulfonyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aralkenyl group, a substituted or unsubstituted alkylaryl group, a substituted or unsubstituted alkylamino group, a substituted or unsubstituted aralkylamino group, a substituted or unsubstituted heteroarylamine group, a substituted or unsubstituted arylamine group, a substituted or unsubstituted arylphosphino group, a substituted or unsubstituted phosphine oxide group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group.

4. The organic mixture according to claim 3, characterized in that The structure represented by the general formula (5) is selected from any one of the following structural formulas: 。 5. The organic mixture according to claim 3, characterized in that The structure represented by general formula (6) is selected from any one of the following structural formulas: 。 6. A light emitting device, characterized in that: include: A light-emitting layer and a hole transport unit are sequentially arranged along a first direction; wherein the hole transport unit comprises the first type of organic compound in the organic mixture according to claim 1 or 2; The light-emitting layer comprises the second organic compound in the organic mixture according to any one of claims 3 to 5.

7. The light emitting device according to claim 6, characterized in that: The hole transport unit includes a hole injection layer, a hole transport layer and an electron blocking layer; the hole injection layer, the hole transport layer, the electron blocking layer and the light emitting layer are arranged in sequence along the first direction; the electron blocking layer includes the first type of organic compound.

8. The light emitting device according to claim 7, characterized in that: There are multiple electron blocking layers, and the multiple electron blocking layers are arranged along a second direction, and the second direction is perpendicular to the first direction; at least one of the multiple electron blocking layers includes the first type of organic compound.

9. The light emitting device according to any one of claims 6 to 8, characterized in that: There are multiple light-emitting layers, and the multiple light-emitting layers are arranged along a second direction, and the second direction is perpendicular to the first direction; at least one of the multiple light-emitting layers includes the second type of organic compound.

10. The light emitting device according to claim 9, characterized in that: Each of the light-emitting layers includes an N-type host material and a guest material, wherein the N-type host material includes the second type of organic compound.

11. The light emitting device according to claim 10, characterized in that: Each of the light-emitting layers further includes a P-type host material, and the P-type host material is selected from GH2, and the structural formula of GH2 is as follows: 。 12. A light-emitting substrate, characterized in that: The invention comprises a light emitting device as claimed in any one of claims 6 to 11.

13. A light emitting device, characterized in that: It comprises the light emitting substrate as claimed in claim 12.

Images