Organic light-emitting devices, methods for manufacturing them, and compositions thereof.

Abstract

The present invention relates to an organic light-emitting device, which comprises an anode, a cathode, at least two light-emitting layers, and at least one charge generation layer, wherein the at least two light-emitting layers are arranged between the anode and the cathode, and wherein the at least one charge generation layer is arranged between two of the at least two light-emitting layers; wherein the charge generation layer comprises an n-type sublayer and a p-type sublayer, wherein the n-type sublayer comprises a) at least one first organic compound, wherein the first organic compound comprises at least one P=X group, wherein X is selected from O, S and Se; b) at least one second organic compound, wherein the second organic compound comprises at least one metal complexing group, or two metal complexing groups; and c) a zero-valent metal dopant, wherein the zero-valent metal dopant is a metal selected from alkali metals, alkaline earth metals, rare earth metals, Group 3 transition metals and mixtures thereof; and relates to a method for preparing the organic light-emitting device and a composition used therein.

Description

Technical Field

[0001] The present invention relates to organic light emitting devices and methods for preparing the same. The present invention also relates to compositions used in such devices. Background Art

[0002] Organic light emitting diode (OLED), is a self-luminous device, with wide viewing angle, excellent contrast, rapid response, high brightness, excellent driving voltage characteristics and color reproduction. Typical OLED includes anode, hole transport layer (HTL), light emitting layer (EML), electron transport layer (ETL) and cathode, which are sequentially stacked on a substrate. In this regard, HTL, EML and ETL are thin films formed by organic compounds and / or organometallic compounds.

[0003] When voltage is applied to the anode and cathode, holes injected from the anode electrode move to the EML via the HTL, and electrons injected from the cathode electrode move to the EML via the ETL. Holes and electrons recombine in the EML to generate excitons. When the excitons drop from the excited state to the ground state, light is emitted. The injection and flow of holes and electrons should be balanced so that the OLED having the above structure has excellent efficiency.

[0004] Also known in the art are OLEDs comprising two or more light-emitting layers between the two electrodes. Such OLEDs are called tandem OLEDs. In such tandem OLEDs, a charge generation layer is included between the two light-emitting layers, wherein the n-type charge generation layer provides electrons to the light-emitting layer arranged closer to the anode, and the p-type generation layer provides holes to the light-emitting layer arranged near the cathode. Various materials for preparing such charge generation layers are known in the art.

[0005] However, there is still a need to improve the performance of organic light emitting diodes or materials contained therein, in particular to improve the performance of (tandem) organic light emitting diodes comprising a charge generation layer with respect to operating voltage and voltage rise over time.

[0006] Therefore, the object of the present invention is to provide an organic light-emitting device that overcomes the disadvantages of the prior art, in particular to provide an organic light-emitting device with a reduced operating voltage and a significantly reduced voltage rise over time, or a material suitable for use in such an organic light-emitting device to improve these properties. Summary of the invention

[0007] The above object is achieved by an organic light-emitting device, which comprises an anode, a cathode, at least two light-emitting layers, and at least one charge generation layer, wherein the at least two light-emitting layers are arranged between the anode and the cathode, and wherein the at least one charge generation layer is arranged between two of the at least two light-emitting layers; wherein the charge generation layer comprises an n-type sublayer and a p-type sublayer, wherein the n-type sublayer comprises a) at least one first organic compound, wherein the first organic compound comprises at least one P=X group, wherein X is selected from O, S and Se; b) at least one second organic compound, wherein the second organic compound comprises at least one metal complexing group, or two metal complexing groups; and c) a zero-valent metal dopant, wherein the zero-valent metal dopant is a metal selected from alkali metals, alkaline earth metals, rare earth metals, Group 3 transition metals and mixtures thereof.

[0008] The present inventors have surprisingly found that an organic light emitting device comprising two or more light emitting layers and a charge generating layer as defined herein is suitable for improving the performance of the organic light emitting device, in particular with respect to operating voltage and voltage rise over time.

[0009] The inventive organic light-emitting device according to the present invention comprises at least two light-emitting layers. However, it may be provided that the device comprises three or more light-emitting layers. In such a case, more than one charge generation layer (each comprising an n-type sublayer and a p-sublayer as defined herein) may be provided between two of those layers. In this regard, it may be provided that one charge generation layer is provided between two light-emitting layers, respectively.

[0010] As referred to herein, the metal complexing group is a group suitable for forming a metal complex (coordination complex) with a metal ion. The formed metal complex may include one or more metal ions coordinated by one or more organic compounds comprising the metal complexing group. The metal complexing group may be a group having a lone pair of electrons suitable for forming a coordinated covalent bond (coordination bond, coordination bond) with the metal ion.

[0011] The charge generation layer may further comprise an intermediate layer arranged between the n-type sublayer and the p-type sublayer. The n-type sublayer and / or the p-type sublayer may be in direct contact with the intermediate layer. The intermediate layer may comprise a metal complex or may consist of a metal complex. In this way, the properties of the organic light-emitting device may be further improved, in particular with respect to the operating voltage and the voltage rise over time.

[0012] In this regard, the metal complex contained in or forming the intermediate layer may be a compound having the structure

[0013]

[0014] However, other suitable metal complexes known in the art for this purpose may also be used.

[0015] The organic light-emitting device of the present invention comprises an anode, a cathode, at least two light-emitting layers, and at least one charge generation layer, wherein the at least two light-emitting layers are arranged between the anode and the cathode, and wherein the at least one charge generation layer is arranged between two of the at least two light-emitting layers; wherein the charge generation layer comprises an n-type sublayer and a p-type sublayer, wherein the n-type sublayer comprises a) at least one first organic compound, the first organic compound comprises at least one P=X group, wherein X is selected from O, S and Se; b) at least one second organic compound, the second organic compound comprises at least one metal complexing group, or two metal complexing groups; wherein the first organic compound is different from the second organic compound; and c) a zero-valent metal dopant, wherein the zero-valent metal dopant is a metal selected from alkali metals, alkaline earth metals, rare earth metals, Group 3 transition metals and mixtures thereof.

[0016] The first organic compound comprises at least one P═X group, wherein X is selected from O, S and Se; b) at least one second organic compound, the second organic compounds of the invention comprising at least one metal complexing group being different from each other. In this way, the properties of the organic light-emitting device can be further improved, in particular with regard to the operating voltage and the voltage rise over time.

[0017] The first organic compound and / or the second organic compound may contain a conjugated system of at least 10 delocalized electrons, or the first organic compound and the second organic compound may contain a system of at least 10 delocalized electrons, respectively. In this way, the properties of the organic light-emitting device, in particular the properties with respect to the operating voltage and the voltage rise over time, can be further improved.

[0018] As referred to herein, the conjugated system of delocalized electrons is a system with alternating π-bonds and σ-bonds, wherein, optionally, one or more diatomic structural units having π bonds between their atoms can be replaced by atoms with at least one lone pair of electrons, usually by divalent O or S atoms. Alternatively or in addition, the system with alternating π-bonds and σ-bonds can be embedded in one or more isolated boron atoms having only six valence electrons and one empty orbital. Preferably, according to Hückel's rule, the conjugated system of delocalized electrons comprises at least one aromatic ring. More preferably, the conjugated system of delocalized electrons comprises a fused aromatic skeleton containing at least 10 delocalized electrons, such as a naphthalene, anthracene, phenanthrene, pyrene, benzofuran or benzothiophene skeleton. Also preferably, the conjugated system of delocalized electrons can be composed of at least two directly connected aromatic rings, the simplest examples of such systems being biphenyl, bithiophene, phenylthiophene, furylthiophene, and the like.

[0019] The first organic compound can be represented by the following formula (I):

[0020]

[0021] wherein X is selected from O, S and Se;

[0022] R 1 , R 2 and R 3 Independently selected from C1 to C 30 Alkyl, C3 to C 30 Cycloalkyl, C2 to C 30 Heteroalkyl, C6 to C 60 Aryl, C2 to C 50 Heteroaryl, C1 to C 30 Alkoxy, C3 to C 30 Cycloalkoxy, C6 to C 30 aryloxy;

[0023] Where R 1 , R 2 and R 3 Each may independently contain one or more other groups: C6 to C 18 Aryl, C3 to C 20 heteroaryl, -PO(R')2 (R' is preferably phenyl and / or methyl), D, F or CN, C1 to C 16 Alkyl, C1 to C 16 Alkoxy, nitrile,

[0024] Among them, if R 1 , R 2 and R 3 If one or more of the carbon-containing groups is a carbon-containing group comprising at least one carbon atom directly connected to at least one hydrogen atom, the hydrogen atoms contained in the carbon-containing groups may be partially or completely replaced by deuterium atoms and / or fluorine atoms. In this way, the properties of the organic light-emitting device, in particular the properties with respect to the operating voltage and the voltage rise over time, can be further improved.

[0025] The first organic compound can be represented by the following formula (I):

[0026]

[0027] wherein X is selected from O, S and Se;

[0028] R 1 , R 2 and R 3 Independently selected from C1 to C 30 Alkyl, C3 to C 30 Cycloalkyl, C2 to C 30Heteroalkyl, C6 to C 60 Aryl, C2 to C 50 Heteroaryl, C1 to C 30 Alkoxy, C3 to C 30 Cycloalkoxy, C6 to C 30 aryloxy;

[0029] Where R 1 , R 2 and R 3 At least two of may be connected to each other to form a 5-, 6- or 7-membered ring together with the P atom,

[0030] Where R 1 , R 2 and R 3 Each may independently contain one or more other groups: C6 to C 18 Aryl, C3 to C 20 heteroaryl, -PO(R')2 (R' is preferably phenyl and / or methyl), D, F or CN, C1 to C 16 Alkyl, C1 to C 16 Alkoxy, nitrile,

[0031] Among them, if R 1 , R 2 and R 3 If one or more of the carbon-containing groups is a carbon-containing group comprising at least one carbon atom directly connected to at least one hydrogen atom, the hydrogen atoms contained in the carbon-containing groups may be partially or completely replaced by deuterium atoms and / or fluorine atoms. In this way, the properties of the organic light-emitting device, in particular the properties with respect to the operating voltage and the voltage rise over time, can be further improved.

[0032] In the compound of formula (I), if R 1 , R 2 and R 3 At least two of the groups are connected to each other to form a ring together with the P atom, then the connection may include incorporating other groups between the two groups to be connected, as long as a 5-, 6- or 7-membered ring is formed. 1 and R 3 In order to form a ring, another divalent component is introduced between the groups, and the divalent component forms a bond with each of these groups. The same also applies to R 1 and R 2 For and / or R 2 and R 3 Yes. In other words, if R 1 and R 2 The groups will be linked together to form a ring, then R 1 can be connected to one side of the divalent component and R 2Can be connected to the other side of the divalent component to form a ring. An exemplary structure of this case is the following structure:

[0033]

[0034] Alternatively, the two groups may be linked to each other via a single bond. 1 and R 2 or R 2 and R 3 When the groups are to be connected, a single bond is formed between these groups. A corresponding exemplary compound of this case is the following structure

[0035]

[0036] Another exemplary structure is the following structure

[0037]

[0038] R 1 , R 2 and R 3 At least one of the may comprise a conjugated system of at least 10 delocalized electrons. In this way, the properties of the organic light-emitting device may be further improved, in particular with regard to the operating voltage and the voltage rise over time.

[0039] As referred to herein, the conjugated system of delocalized electrons is a system with alternating π-bonds and σ-bonds, wherein, optionally, one or more diatomic structural units having π bonds between their atoms can be replaced by atoms with at least one lone pair of electrons, usually by divalent O or S atoms. Alternatively or in addition, the system with alternating π-bonds and σ-bonds can be embedded in one or more isolated boron atoms having only six valence electrons and one empty orbital. Preferably, according to Huckel's rule, the conjugated system of delocalized electrons comprises at least one aromatic ring. More preferably, the conjugated system of delocalized electrons comprises a fused aromatic skeleton containing at least 10 delocalized electrons, such as a naphthalene, anthracene, phenanthrene, pyrene, benzofuran or benzothiophene skeleton. Also preferably, the conjugated system of delocalized electrons can be composed of at least two directly connected aromatic rings, the simplest examples of such systems being biphenyl, bithiophene, phenylthiophene, furylthiophene, and the like.

[0040] According to another aspect of the present invention, the first organic compound can be represented by the following formula (I):

[0041]

[0042] wherein X is selected from O, S and Se;

[0043] R 1 , R 2and R 3 Independently selected from C1 to C 30 Alkyl, C3 to C 30 Cycloalkyl, C2 to C 30 Heteroalkyl, C6 to C 60 Aryl, C2 to C 50 Heteroaryl, C1 to C 30 Alkoxy, C3 to C 30 Cycloalkoxy, C6 to C 30 aryloxy;

[0044] Where R 1 , R 2 and R 3 Each may independently contain one or more other groups: C6 to C 18 Aryl, C3 to C 20 heteroaryl, -PO(R')2 (R' is preferably phenyl and / or methyl), D, F or CN, C1 to C 16 Alkyl, C1 to C 16 Alkoxy, nitrile;

[0045] Where R 1 , R 2 or R 3 At least two of which are independently C1 to C 30 Alkyl group.

[0046] According to another aspect of the present invention, the first organic compound can be represented by the following formula (I):

[0047]

[0048] wherein X is selected from O, S and Se;

[0049] R 1 , R 2 and R 3 Independently selected from C1 to C 30 Alkyl, C3 to C 30 Cycloalkyl, C2 to C 30 Heteroalkyl, C6 to C 60 Aryl, C2 to C 50 Heteroaryl, C1 to C 30 Alkoxy, C3 to C 30 Cycloalkoxy, C6 to C 30 aryloxy;

[0050] Where R 1 , R 2 and R 3 Each may independently contain one or more other groups: C6 to C 18 Aryl, C3 to C 20heteroaryl, -PO(R')2 (R' is preferably phenyl and / or methyl), D, F or CN, C1 to C 16 Alkyl, C1 to C 16 Alkoxy, nitrile;

[0051] Where R 1 , R 2 or R 3 At least two of them are methyl groups.

[0052] R 1 , R 2 and R 3 At least one of, or R 1 , R 2 and R 3 Two of them can be phenyl, or R 1 , R 2 and R 3 At least one, or both, of them may be a C1 to C4 alkyl group, or a methyl group.

[0053] If R 1 , R 2 and R 3 At least one selected from C6 to C 60 Aryl and C2 to C 50 Heteroaryl, where R 1 , R 2 and R 3 At least one of the following may independently contain one or more other groups: C6 to C 18 Aryl, C3 to C 20 heteroaryl, -PO(R')2 (R' is preferably phenyl and / or methyl), D, F or CN, C1 to C 16 Alkyl, C1 to C 16 Alkoxy, nitrile.

[0054] If R 1 , R 2 and R 3 At least one of the carbon-containing groups is a carbon-containing group comprising at least one carbon atom directly connected to at least one hydrogen atom, the hydrogen atoms contained in the carbon-containing group may be partially or completely replaced by deuterium atoms and / or fluorine atoms.

[0055] The first organic compound may be one or more selected from the following compounds

[0056]

[0057]

[0058]

[0059]

[0060]

[0061]

[0062] According to another aspect of the present invention, the first organic compound represented by formula (I) is completely conjugated.

[0063] The metal complexing group may be a trivalent nitrogen atom. Preferably, the trivalent nitrogen atom is contained in a second organic compound having a structure represented by the following formula:

[0064]

[0065] wherein * independently represents a bond to a carbon atom or a nitrogen atom, preferably a carbon atom, contained in the second organic compound.

[0066] In this way, the properties of the organic light-emitting component, in particular with regard to the operating voltage and the voltage rise over time, can be further improved.

[0067] The first organic compound and / or the second organic compound may independently have a molecular weight of 200 to 1,000 g / mol, or a molecular weight of 300 to 1,000 g / mol. In this way, the properties of the organic light-emitting device, in particular with respect to the operating voltage and the voltage rise over time, can be further improved.

[0068] The second organic compound may include at least one metal complexing group, the metal complexing group including a C2 to C 30 A heteroaryl group, preferably two C2 to C 30 Heteroaryl groups, preferably benzo[h]quinoline. In this way, the properties of the organic light-emitting device can be further improved, in particular with regard to the operating voltage and the voltage rise over time.

[0069] Benzo[h]quinoline refers to the following moiety

[0070]

[0071] The second organic compound may contain at least two metal complexing groups, for example two C2 to C 30 Preferably, the second organic compound may comprise two C2 to C 30 In one embodiment, the C2 to C 30The heteroaryl group may comprise 1,10-phenanthroline and / or pyrido[3,2-h]quinazoline structural components. In this way, the properties of the organic light-emitting device may be further improved, in particular with regard to the operating voltage and the voltage rise over time.

[0072] 1,10-Phenanthroline refers to the following structural components:

[0073]

[0074] Pyrido[3,2-h]quinazoline refers to the following structural moiety:

[0075]

[0076] The second organic compound may be one or more of the following compounds, or may be selected from other similar compounds disclosed in US2018166647AA

[0077]

[0078]

[0079]

[0080]

[0081]

[0082]

[0083] The second organic compound may contain at least two metal complexing groups, for example two C2 to C 30 Preferably, the second organic compound may comprise two C2 to C 30 In one embodiment, the C2 to C 30 The heteroaryl group may comprise a bipyridine or terpyridine group, which may be substituted or unsubstituted, wherein one or more substituents, if present, are preferably selected from such substituents as indicated herein for the specific compounds. In this way, the properties of the organic light-emitting device, in particular with respect to the operating voltage and the voltage rise over time, may be further improved.

[0084] Bipyridine refers to the following structural components:

[0085]

[0086] Terpyridine refers to the following structural components:

[0087]

[0088] The second organic compound may be one or more of the following compounds, or may be selected from other similar compounds:

[0089]

[0090]

[0091]

[0092]

[0093] The zero-valent metal dopant may be selected from Li, Na, K, Rb, Cs, Mg, Ca, Sr, Ba, Yb, Sm, Eu, Nd, Tb, Gd, Ce, La, Sc and Y, or Li, Na, Mg, Ca, Ba, Yb, or Li, Mg, Ba, Yb. In this way, the properties of the organic light-emitting device may be further improved, in particular with regard to the operating voltage and the voltage rise over time.

[0094] The objects of the present invention are also achieved by a method for manufacturing an organic light-emitting device as defined herein, comprising the steps of: a1) evaporating the first organic compound and the second organic compound from different evaporation sources; or a2) co-evaporating the first organic compound and the second organic compound from the same evaporation source; and b) co-depositing the first and second organic compounds on a solid support.

[0095] In this context, a solid support may also refer to an organic layer deposited during a previous processing step.

[0096] In addition, the object of the present invention is achieved by a composition consisting of a first organic compound and a second organic compound, wherein the first organic compound is a compound containing at least one P=X group, wherein X is selected from O, S or Se; and the second organic compound contains at least one metal complexing group, or two metal complexing groups. In this regard, the preferred embodiments of the first organic compound and the second organic compound for the above-mentioned organic light-emitting device are also preferred embodiments for the composition.

[0097] The composition consisting of the first organic compound and the second organic compound may be in the form of a heterogeneous mixture.

[0098] A heterogeneous mixture is understood to be a heterogeneous mixture which preferably consists of a physical mixture. The heterogeneity encompassed in this context is generally recognizable by optical microscopy, for example by polarizing microscopy or by fluorescence microscopy.

[0099] The composition consisting of the first organic compound and the second organic compound may be a homogeneous composition.

[0100] A homogeneous composition is understood to be a homogeneous composition consisting of a single phase. Preferably, the single phase is solid. In addition, the purpose of this article is achieved by a semiconductor material consisting of a first organic compound and a second organic compound, or comprising the first organic compound and the second organic compound, wherein the first organic compound is a compound comprising at least one P=X group, wherein X is selected from O, S or Se; and the second organic compound comprises at least one metal complexing group, or two metal complexing groups. The preferred embodiments of the first organic compound and the second organic compound for the organic light-emitting device are also preferred embodiments for the semiconductor material.

[0101] In addition, the object of the present invention is achieved by a semiconductor material composed of the following substances: a) a first organic compound, b) a second organic compound and c) a zero-valent metal dopant, wherein the zero-valent metal dopant is a metal selected from alkali metals, alkaline earth metals, rare earth metals, Group 3 transition metals and mixtures thereof. Alternatively, the semiconductor material is composed of the following substances: a) a first organic compound, wherein the first organic compound is a compound containing at least one P=X group, wherein X is selected from O, S or Se; b) a second organic compound, and the second organic compound contains at least one metal complexing group, or two metal complexing groups, and c) a zero-valent metal dopant, wherein the zero-valent metal dopant is a metal selected from alkali metals, alkaline earth metals, rare earth metals, Group 3 transition metals and mixtures thereof. The preferred embodiments of the first organic compound, the second organic compound and the zero-valent metal dopant for the organic light-emitting device are also preferred embodiments for the semiconductor material.

[0102] Other layers

[0103] According to the present invention, in addition to the layers mentioned above, the organic light emitting device may further comprise other layers. Exemplary embodiments of the corresponding layers are described below:

[0104] Base

[0105] The substrate may be any substrate commonly used in the manufacture of organic light emitting devices. If light is to be emitted through the substrate, the substrate should be a transparent or translucent material, such as a glass substrate or a transparent plastic substrate. If light is to be emitted through the top surface, the substrate may be a transparent as well as an opaque material, such as a glass substrate, a plastic substrate, a metal substrate or a silicon substrate.

[0106] Anode electrode

[0107] Any one of the first electrode or the second electrode can be an anode electrode. The anode electrode can be formed by depositing or sputtering a material for forming the anode electrode. The material for forming the anode electrode can be a material with a high work function so as to promote hole injection. The anode material can also be selected from a low work function material (i.e., aluminum). The anode electrode can be a transparent or reflective electrode. Transparent conductive oxides, such as indium tin oxide (ITO), indium zinc oxide (IZO), tin dioxide (SnO2), aluminum zinc oxide (AlZO) and zinc oxide (ZnO), can be used to form the anode electrode. Metals, typically silver (Ag), gold (Au) or metal alloys, can also be used to form the anode electrode.

[0108] Hole injection layer

[0109] The hole injection layer (HIL) can be formed on the anode electrode by vacuum deposition, spin coating, printing, casting, slot die coating, Langmuir-Blodgett (LB) deposition, etc. When vacuum deposition is used to form the HIL, the deposition conditions may vary depending on the compound used to form the HIL and the desired structure and thermal properties of the HIL. However, in general, the conditions for vacuum deposition may include a deposition temperature of 100° C. to 500° C., a pressure of 10 -8 Up to 10 -3 Torr (1 Torr equals 133.322 Pa) and the deposition rate is 0.1 to 10 nm / sec.

[0110] When the HIL is formed using spin coating or printing, the coating conditions may vary according to the compound used to form the HIL and the desired structure and thermal properties of the HIL. For example, the coating conditions may include a coating speed of about 2000 rpm to about 5000 rpm and a heat treatment temperature of about 80° C. to about 200° C. After coating, heat treatment is performed to remove the solvent.

[0111] The HIL may be formed of any compound that is generally used to form a HIL. Examples of compounds that can be used to form the HIL include phthalocyanine compounds such as copper phthalocyanine (CuPc), 4,4',4"-tris(3-methylphenylphenylamino)triphenylamine (m-MTDATA), TDATA, 2T-NATA, polyaniline / dodecylbenzenesulfonic acid (Pani / DBSA), poly(3,4-ethylenedioxythiophene) / poly(4-styrenesulfonate) (PEDOT / PSS), polyaniline / camphorsulfonic acid (Pani / CSA), and polyaniline / poly(4-styrenesulfonate) (PANI / PSS).

[0112] In such a case, the HIL may be a pure layer of a p-type dopant, or may be selected from a hole transport host compound doped with a p-type dopant. Typical examples of known redox-doped hole transport materials are: copper phthalocyanine (CuPc) with a HOMO level of about -5.2 eV, which is doped with tetrafluoro-tetracyanoquinodimethane (F4TCNQ) with a LUMO level of about -5.2 eV; zinc phthalocyanine (ZnPc) doped with F4TCNQ (HOMO = -5.2 eV); α-NPD (N,N'-bis(naphthalene-1-yl)-N,N'-bis(phenyl)-benzidine) doped with F4TCNQ, α-NPD doped with 2,2'-(perfluoronaphthalene-2,6-diylidene)dimalononitrile (PD1), α-NPD doped with 2,2',2"-(cyclopropane-1,2,3-triylidene)tris(2-(p-cyanotetrafluorophenyl)acetonitrile) (PD2). The dopant concentration can be selected from 1 to 20 weight %, more preferably from 3 weight % to 10 weight %.

[0113] The thickness of the HIL may be within a range of about 1 nm to about 100 nm, for example, within a range of about 1 nm to about 25 nm. When the thickness of the HIL is within this range, the HIL may have excellent hole injection characteristics without significantly deteriorating driving voltage.

[0114] Hole transport layer

[0115] A hole transport layer (HIL) can be formed on the HIL by vacuum deposition, spin coating, slot die coating, printing, casting, Langmuir-Blodgett (LB) deposition, etc. When the HTL is formed by vacuum deposition or spin coating, the conditions for deposition and coating may be similar to those for forming the HIL. However, the conditions for vacuum or solution deposition may vary according to the compound used to form the HTL.

[0116] The HTL may be formed of any compound commonly used to form the HTL. Compounds that may be suitably used are disclosed in, for example, Yasuhiko Shirota and Hiroshi Kageyama, Chem. Rev. 2007, 107, 953-1010 and are incorporated herein by reference. Examples of compounds that may be used to form the HTL are: carbazole derivatives, such as N-phenylcarbazole or polyvinylcarbazole; benzidine derivatives, such as N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1-biphenyl]-4,4'-diamine (TPD), or N,N'-di(naphthalene-1-yl)-N,N'-diphenylbenzidine (α-NPD); and triphenylamine-based compounds, such as 4,4',4"-tri(N-carbazolyl)triphenylamine (TCTA). Among these compounds, TCTA may transport holes and inhibit diffusion of excitons into the EML.

[0117] The thickness of the HTL may be in the range of about 5 nm to about 250 nm, preferably about 10 nm to about 200 nm, more preferably about 20 nm to about 190 nm, more preferably about 40 nm to about 180 nm, more preferably about 60 nm to about 170 nm, more preferably about 80 nm to about 160 nm, more preferably about 100 nm to about 160 nm, more preferably about 120 nm to about 140 nm. The preferred HTL thickness may be 170 nm to 200 nm.

[0118] When the thickness of the HTL is within this range, the HTL may have excellent hole transport characteristics without significant deterioration in driving voltage.

[0119] Electron blocking layer

[0120] The function of the electron blocking layer (EBL) is to prevent electrons from being transferred from the light-emitting layer to the hole transport layer, thereby confining the electrons in the light-emitting layer. Thus, the efficiency, operating voltage and / or life are improved. Typically, the electron blocking layer comprises a triarylamine compound. The triarylamine compound may have a LUMO energy level that is closer to the vacuum energy level than the LUMO energy level of the hole transport layer. Compared with the HOMO energy level of the hole transport layer, the electron blocking layer may have a HOMO energy level that is further away from the vacuum energy level. The thickness of the electron blocking layer may be selected between 2 and 20 nm.

[0121] The electron blocking layer may include a compound of Formula Z below (Z).

[0122]

[0123] In formula Z, CY1 and CY2 are the same as or different from each other and each independently represents a benzene ring or a naphthalene ring, Ar1 to Ar3 are the same as or different from each other and each independently selected from hydrogen, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, and a substituted or unsubstituted heteroaryl group having 5 to 30 carbon atoms, Ar4 is selected from a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted terphenyl group, a substituted or unsubstituted terphenylidene group, and a substituted or unsubstituted heteroaryl group having 5 to 30 carbon atoms, and L is a substituted or unsubstituted aryl substituent group having 6 to 30 carbon atoms.

[0124] If the electron blocking layer has a high triplet energy level, it may also be referred to as a triplet control layer.

[0125] If a green phosphorescent or blue phosphorescent luminescent layer is used, the function of the triplet control layer is to reduce the quenching of the triplet state. Thus, a higher luminous efficiency from the phosphorescent luminescent layer can be achieved. The triplet control layer is selected from triarylamine compounds whose triplet energy level is higher than the triplet energy level of the phosphorescent luminescent body in the adjacent luminescent layer. Suitable compounds for triplet control layers, in particular triarylamine compounds, are described in EP 2 722 908A1.

[0126] Emission layer (EML)

[0127] The at least two EMLs may be independently formed on the HTL by vacuum deposition, spin coating, slot die coating, printing, casting, LB deposition, etc. When the EML is formed by vacuum deposition or spin coating, the conditions for deposition and coating may be similar to those for forming the HIL. However, the conditions for deposition and coating may vary depending on the compound used to form the EML.

[0128] Each light-emitting layer (EML) may be formed of a combination of a host and a light-emitting dopant. Examples of the host are: Alq3, 4,4'-N,N'-dicarbazole biphenyl (CBP), poly(n-vinyl carbazole) (PVK), 9,10-di(naphthalene-2-yl)anthracene (ADN), 4,4',4"-tri(carbazole-9-yl)-triphenylamine (TCTA), 1,3,5-tri(N-phenylbenzimidazol-2-yl)benzene (TPBI), 3-tert-butyl-9,10-di-2-naphthylanthracene (TBADN), distyrylarene (DSA), bis(2-(2-hydroxyphenyl)benzothiazole)zinc (Zn(BTZ)2), G3 below, compound 1 below, and compound 2 below.

[0129]

[0130] The emitter dopant may be a phosphorescent or fluorescent emitter. Phosphorescent emitters and emitters that emit light via a thermally activated delayed fluorescence (TADF) mechanism may be preferred due to their higher efficiency. The emitter may be a small molecule or a polymer.

[0131] Examples of red emitter dopants are PtOEP, Ir(piq)3 and Btp2Ir(acac), but are not limited thereto. These compounds are phosphorescent emitters, however, red fluorescent emitter dopants may also be used.

[0132]

[0133] Examples of green phosphorescent emitter dopants are Ir(ppy)3 (ppy = phenylpyridine), Ir(ppy)2(acac), Ir(mpyp)3 shown below. Compound 3 is an example of a green fluorescent emitter, and its structure is shown below.

[0134]

[0135]

[0136] Examples of blue phosphorescent emitter dopants are F2Irpic, (F2ppy)2Ir(tmd) and Ir(dfppz)3, terfluorene, the structure of which is shown below. 4,4'-bis(4-diphenylaminophenylvinyl)biphenyl (DPAVBi), 2,5,8,11-tetra-tert-butylperylene (TBPe) and compound 4 below are examples of blue fluorescent emitter dopants.

[0137]

[0138] The amount of the luminophore dopant may be in the range of about 0.01 to about 50 parts by weight based on 100 parts by weight of the host. Alternatively, the luminescent layer may be composed of a luminescent polymer. The thickness of the EML may be about 10 nm to about 100 nm, for example, about 20 nm to about 60 nm. When the thickness of the EML is within this range, the EML may have excellent luminescence without significant damage to the driving voltage.

[0139] Hole Blocking Layer (HBL)

[0140] A hole blocking layer (HBL) may be formed on the EML to prevent holes from diffusing into the ETL by using vacuum deposition, spin coating, slot die coating, printing, casting, LB deposition, etc. When the EML includes a phosphorescent dopant, the HBL may also have a triplet exciton blocking function.

[0141] When the HBL is formed by vacuum deposition or spin coating, the conditions for deposition and coating may be similar to those for forming the HIL. However, the conditions for deposition and coating may vary according to the compound used to form the HBL. Any compound commonly used to form the HBL may be used. Examples of the compound used to form the HBL include Oxadiazole derivatives, triazole derivatives and phenanthroline derivatives.

[0142] The thickness of the HBL may be in the range of about 5 nm to about 100 nm, for example, about 10 nm to about 30 nm. When the thickness of the HBL is within this range, the HBL may have excellent hole blocking properties without significant deterioration in driving voltage.

[0143] Electron Transport Layer (ETL)

[0144] The OLED of the present invention may contain an electron transport layer (ETL).

[0145] According to various embodiments, the OLED may include an electron transport layer or an electron transport layer stack structure including at least one first electron transport sublayer and at least one second electron transport sublayer.

[0146] By properly adjusting the energy level of a specific ETL layer, the injection and transport of electrons can be controlled, and holes can be effectively blocked. Therefore, the OLED can have a long lifespan.

[0147] The electron transport layer of the organic light-emitting device may include an organic electron transport matrix (ETM) material. In addition, the electron transport layer may include one or more n-type dopants. There is no particular restriction on suitable compounds for ETM. In one embodiment, the electron transport matrix compound consists of covalently bound atoms. Preferably, the electron transport matrix compound contains a conjugated system of at least 6, more preferably at least 10 delocalized electrons. In one embodiment, the conjugated system of the delocalized electrons may be contained in an aromatic or heteroaromatic structural component, as disclosed in, for example, EP 1 970 371 A1 or WO 2013 / 079217 A1.

[0148] In one embodiment, the electron transport layer may be electrically doped with an n-type electrical dopant. In another embodiment, the electron transport layer may include a second electron transport sublayer disposed closer to the cathode than the first electron transport sublayer, and only the second electron transport sublayer may include an n-type electrical dopant.

[0149] The n-type electrical dopant may be selected from electropositive elemental metals, and / or metal salts and metal complexes selected from electropositive metals, in particular elemental forms, salts and / or complexes of metals selected from alkali metals, alkaline earth metals and rare earth metals.

[0150] Electron injection layer (EIL)

[0151] An optional EIL that can facilitate electron injection from the cathode can be formed on the ETL, preferably directly on the electron transport layer. Examples of materials for forming the EIL include 8-hydroxyquinoline lithium (LiQ), LiF, NaCl, CsF, Li2O, BaO, Ca, Ba, Yb, Mg, which are known in the art. The deposition and coating conditions for forming the EIL are similar to those for forming the HIL, but the deposition and coating conditions may vary according to the material used to form the EIL.

[0152] The thickness of the EIL may be in the range of about 0.1 nm to about 10 nm, for example, in the range of about 0.5 nm to about 9 nm. When the thickness of the EIL is within this range, the EIL may have satisfactory electron injection properties without significantly impairing driving voltage.

[0153] Cathode electrode

[0154] If the EIL exists, the cathode electrode is formed on the EIL. The cathode electrode may be formed of a metal, an alloy, a conductive compound, or a mixture thereof. The cathode electrode may have a low work function. For example, the cathode electrode may be formed of lithium (Li), magnesium (Mg), aluminum (Al), aluminum (Al)-lithium (Li), calcium (Ca), barium (Ba), ytterbium (Yb), magnesium (Mg)-indium (In), magnesium (Mg)-silver (Ag), etc. Alternatively, the cathode electrode may be formed of a transparent conductive oxide such as ITO or IZO.

[0155] The thickness of the cathode electrode may be in the range of about 5 nm to about 1000 nm, for example, in the range of about 10 nm to about 100 nm. When the thickness of the cathode electrode is in the range of about 5 nm to about 50 nm, the cathode electrode may be transparent or translucent even if it is formed of a metal or a metal alloy.

[0156] It is to be understood that the cathode electrode is not part of the electron injection layer or the electron transport layer.

[0157] Charge generation layer / hole generation layer

[0158] The charge generation layer (CGL) consists of two layers.

[0159] The charge generation layer is a pn junction connecting an n-type charge generation layer (electron generation layer) and a p-type charge generation layer (hole generation layer). The n-side of the pn junction generates electrons and injects them into the layer adjacent in the direction of the anode. Similarly, the p-side of the pn junction generates holes and injects them into the layer adjacent in the direction of the cathode.

[0160] The charge generation layer is used in a tandem device, for example, in a tandem OLED comprising two or more light-emitting layers between two electrodes. In a tandem OLED comprising two light-emitting layers, an n-type charge generation layer provides electrons to a first light-emitting layer arranged near the anode, while a p-type charge generation layer provides holes to a second light-emitting layer arranged between the first light-emitting layer and the cathode.

[0161] The hole generation layer can be composed of an organic matrix material doped with a p-type dopant. Suitable matrix materials for the hole generation layer can be materials conventionally used as hole injection and / or hole transport matrix materials. The p-type dopant for the hole generation layer can also be a conventional material. For example, the p-type dopant can be one selected from tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ), derivatives of tetracyanoquinodimethane, axialene derivatives, iodine, FeCl3, FeF3 and SbCl5. The host can also be one selected from N,N'-di(naphthalene-1-yl)-N,N-diphenyl-benzidine (NPB), N,N'-diphenyl-N,N'-bis(3-methylphenyl)-1,1-biphenyl-4,4'-diamine (TPD) and N,N',N'-tetranaphthyl-benzidine (TNB).

[0162] According to the present invention, at least one n-type charge generation layer contained in the organic light-emitting device of the present invention is an n-type sublayer as defined herein. If the organic light-emitting device comprises more than one n-type charge generation layer (=n-type sublayer), only at least one of these n-type charge generation layers is defined as defined herein.

[0163] In a preferred embodiment, the n-type charge generation layer comprises a) a first organic compound, b) a second organic compound and c) a zero-valent metal dopant, wherein the zero-valent metal dopant is a metal selected from alkali metals, alkaline earth metals, rare earth metals, Group 3 transition metals and mixtures thereof. Alternatively, the n-type charge generation layer comprises a) a first organic compound, wherein the first organic compound is a compound comprising at least one P=X group, wherein X is selected from O, S or Se; b) a second organic compound, and the second organic compound comprises at least one metal complexing group, or two metal complexing groups, and c) a zero-valent metal dopant, wherein the zero-valent metal dopant is a metal selected from alkali metals, alkaline earth metals, rare earth metals, Group 3 transition metals and mixtures thereof.

[0164] In a preferred embodiment, the n-type charge generation layer is composed of a) a first organic compound, b) a second organic compound and c) a zero-valent metal dopant, wherein the zero-valent metal dopant is a metal selected from alkali metals, alkaline earth metals, rare earth metals, Group 3 transition metals and mixtures thereof. Or the n-type charge generation layer is composed of the following substances: a) a first organic compound, wherein the first organic compound is a compound containing at least one P=X group, wherein X is selected from O, S or Se; b) a second organic compound, and the second organic compound contains at least one metal complexing group, or two metal complexing groups, and c) a zero-valent metal dopant, wherein the zero-valent metal dopant is a metal selected from alkali metals, alkaline earth metals, rare earth metals, Group 3 transition metals and mixtures thereof.

[0165] In a preferred embodiment, the n-type charge generation layer may contain the first organic compound and the second organic compound in a weight % ratio of 05:95 to 50:50, 10:90 to 50:50, 20:80 to 50:50 or 30:70 to 50:50, preferably 10:90 to 50:50, 20:80 to 50:50 or 30:70 to 50:50.

[0166] In a preferred embodiment, the n-type charge generation layer may contain the first organic compound and the second organic compound in a weight % ratio of 95:05 to 50:50, 90:10 to 50:50, 80:20 to 50:50 or 70:30 to 50:50, preferably 90:10 to 50:50, 80:20 to 50:50 or 70:30 to 50:50.

[0167] Alternatively, it may be provided that other n-type charge generation layers (except for the at least one n-type charge generation layer) are formed differently. If the n-type charge generation layer is not an n-type sublayer as defined herein, the n-type charge generation layer may be a pure n-type dopant layer, such as a positive metal layer, or may be composed of an organic matrix material doped with an n-type dopant. In one embodiment, the n-type dopant may be an alkali metal, an alkali metal compound, an alkaline earth metal, or an alkaline earth metal compound. In another embodiment, the metal may be one selected from Li, Na, K, Rb, Cs, Mg, Ca, Sr, Ba, La, Ce, Sm, Eu, Tb, Dy, and Yb. More specifically, the n-type dopant may be one selected from Cs, K, Rb, Mg, Na, Ca, Sr, Eu, and Yb. Suitable matrix materials for the electron generation layer may be materials conventionally used as matrix materials for electron injection or electron transport layers. The matrix material may be, for example, one selected from triazine compounds, hydroxyquinoline derivatives such as tris(8-hydroxyquinoline)aluminum, benzoxazole derivatives, and silanol derivatives.

[0168] In one embodiment, the n-type charge generation layer may include a compound of the following chemical formula X,

[0169]

[0170] Wherein A1 to A6 can each be hydrogen, a halogen atom, a nitrile (-CN), a nitro group (-NO2), a sulfonyl group (-SO2R), a sulfoxide (-SOR), a sulfonamide (-SO2NR), a sulfonate (-SO3R), a trifluoromethyl group (-CF3), an ester (-COOR), an amide (-CONHR or -CONRR'), a substituted or unsubstituted straight or branched C1-C12 alkoxy group, a substituted or unsubstituted straight or branched C1-C12 alkyl group, a substituted or unsubstituted straight or branched C2-C12 alkenyl group, a substituted or unsubstituted aromatic or non-aromatic heterocycle, a substituted or unsubstituted aryl group, a substituted or unsubstituted mono- or diarylamine, a substituted or unsubstituted aralkylamine, etc. Here, the above R and R' can each be a substituted or unsubstituted C1-C60 alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted 5- to 7-membered heterocycle, etc.

[0171] An example of such an n-type charge generation layer may be a layer containing CNHAT

[0172]

[0173] A hole generating layer is disposed on top of the n-type charge generating layer.

[0174] With regard to the organic electronic device manufacturing method, the alternative embodiments outlined above may apply mutatis mutandis. For example, the charge generation layer may be formed to provide an intermediate layer between the n-type sublayer and the p-type sublayer.

[0175] Organic Light Emitting Diode (OLED)

[0176] According to one aspect, the OLED of the present invention may include the following layer structure: the substrate is arranged adjacent to the anode electrode, the anode electrode is arranged adjacent to the first hole injection layer, the first hole injection layer is arranged adjacent to the first hole transport layer, the first hole transport layer is arranged adjacent to the first electron blocking layer, the first electron blocking layer is arranged adjacent to the first light-emitting layer, the first light-emitting layer is arranged adjacent to the first electron transport layer, the first electron transport layer is arranged adjacent to the n-type charge generation layer (n-type sublayer), the n-type charge generation layer is arranged adjacent to the hole generation layer (p-type sublayer), an intermediate layer may be provided between the n-type sublayer and the p-type sublayer, the hole generation layer is arranged adjacent to the second hole transport layer, the second hole transport layer is arranged adjacent to the second electron blocking layer, the second electron blocking layer is arranged adjacent to the second light-emitting layer, and an optional electron transport layer and / or an optional injection layer are arranged between the second light-emitting layer and the cathode electrode.

[0177] The stacked structure of layers can be manufactured by techniques known in the art. For example, one or more layers in the stacked structure can be manufactured by vacuum thermal evaporation.

[0178] With regard to the organic electronic device manufacturing method, the deposition of the plurality of layers may include the step of depositing a p-type sublayer, the deposition comprising evaporating and depositing a fullerene compound in a vacuum. Preferably, all layers are deposited in a vacuum.

[0179] Details and definitions of the invention

[0180] As used herein, organic compounds generally refer to any carbon-containing compound (except for some compounds that are generally referred to as inorganic, such as carbonates, cyanides, carbon dioxide, diamond, etc.). The term organic compound as used herein also includes organometallic compounds such as organometallic compounds, for example metallocenes, etc.

[0181] As used herein, the term "zero valent" refers to a metal in an oxidation state of 0, ie, in particular, a metal with no electrons removed. The zero valent metal may exist in the form of a zero valent atom, a pure metal, an alloy, and the like.

[0182] The term "trivalent" as used herein refers to a nitrogen atom having single and double bonds and containing a lone pair of electrons.

[0183] As used herein, the term "metal complexing group" refers to a group that can form a bond with a metal ion.

[0184] The term "hydrocarbyl group" as used herein is understood to encompass any organic group comprising carbon atoms, in particular organic groups such as alkyl, aryl, heteroaryl, heteroalkyl, in particular such groups which are typically substituents in organic electronics.

[0185] The term "conjugated system" as used herein refers to a system having alternating π-bonds and σ-bonds, or a molecule having alternating single bonds and multiple bonds, i.e. double bonds, or a system having one or more diatomic structural units having π bonds between its atoms and the diatomic structural units can be replaced by atoms with at least one lone pair of electrons, usually by divalent O or S atoms.

[0186] As used herein, the term "alkyl" shall encompass straight chain as well as branched and cyclic alkyl groups. For example, a C3-alkyl group may be selected from n-propyl and isopropyl. Likewise, a C4-alkyl group encompasses n-butyl, sec-butyl and tert-butyl. Likewise, a C6-alkyl group encompasses n-hexyl and cyclohexyl.

[0187] C n The subscript number n in relates to the total number of carbon atoms in the corresponding alkyl, arylene, heteroarylene or aryl group.

[0188] The term "aryl" as used herein shall encompass phenyl (C6-aryl), fused aromatic compounds such as naphthalene, anthracene, phenanthrene, tetracene, etc. Also encompassed are biphenyl and oligophenyls or polyphenyls such as terphenyl, etc. Also encompassed are any other aromatic hydrocarbon substituents such as fluorenyl, etc. Arylene, corresponding heteroarylene, refers to a group to which two other components are attached.

[0189] The term "heteroaryl" as used herein refers to an aryl group wherein at least one carbon atom is replaced by a heteroatom, preferably selected from N, O, S, B or Si.

[0190] The term "halo" refers to an organic compound in which one hydrogen atom is replaced by a halogen atom. The term "perhalo" refers to an organic compound in which all hydrogen atoms are replaced by halogen atoms. The meanings of the terms "fluoro" and "perfluoro" should be understood similarly.

[0191] C n The subscript number n in the -heteroaryl group refers only to the number of carbon atoms excluding the number of heteroatoms. In this context, it is clear that a C3 heteroaryl group is an aromatic compound containing three carbon atoms, such as pyrazole, imidazole, Azoles, thiazoles, etc.

[0192] For the purposes of the present invention, the expression "between" with respect to a layer being between two other layers does not exclude the presence of a further layer that may be arranged between the one layer and one of the two other layers. For the purposes of the present invention, the expression "in direct contact" with respect to two layers being in direct contact with each other means that no further layer is arranged between the two layers. A layer deposited on top of another layer is considered to be in direct contact with this layer.

[0193] In the context of this specification, the term "substantially non-luminescent" or "non-luminescent" means that the contribution of a compound or layer to the visible luminescence spectrum from the device is less than 10%, preferably less than 5%, relative to the visible luminescence spectrum. The visible luminescence spectrum is the emission spectrum with a wavelength of about ≥380nm to about ≤780nm.

[0194] With regard to the organic light-emitting device of the present invention, the compounds mentioned in the experimental part may be most preferred.

[0195] Organic electroluminescent devices (OLEDs) can be bottom or top emitting devices.

[0196] Another aspect relates to a device comprising at least one organic electroluminescent device (OLED).The device comprising an organic light emitting diode is, for example, a display or a lighting panel.

[0197] In the present invention, the following defined terms shall apply with these definitions unless a different definition is given in the claims or elsewhere in this specification.

[0198] In the context of this specification, the term "different" or "different" with respect to host materials means that the host materials differ in their structural formula.

[0199] The energy levels of the highest occupied molecular orbital, also known as the HOMO, and the lowest unoccupied molecular orbital, also known as the LUMO, are measured in electron volts (eV).

[0200] The terms "OLED" and "organic light emitting diode" are used concurrently and have the same meaning. The term "organic electroluminescent device" as used herein may include both organic light emitting diodes as well as organic light emitting transistors (OLETs).

[0201] As used herein, "weight percent," "weight %," "percent weight," "% weight," parts by weight, and variations thereof, represent a composition, component, substance, or agent as the weight of the component, substance, or agent of the corresponding electron transport layer divided by the total weight of its corresponding electron transport layer, multiplied by 100. It is to be understood that the total weight percent amount of all components, substances, and agents of the corresponding electron transport layer and electron injection layer is selected so as not to exceed 100 weight percent.

[0202] As used herein, "volume percent," "volume %," "percent volume," "% volume," and variations thereof, represent a composition, component, substance, or agent as the volume of the component, substance, or agent of the corresponding electron transport layer divided by the total volume of its corresponding electron transport layer, multiplied by 100. It is to be understood that the total volume percent amount of all components, substances, and agents of the cathode layer is selected so as not to exceed 100 volume percent.

[0203] All numerical values ​​herein are assumed to be modified by the term "about", whether or not explicitly stated. As used herein, the term "about" refers to the amount of variation that can occur. Whether or not modified by the term "about", the claims include equivalents of that amount.

[0204] It should be noted that as used in the specification and claims, the singular forms "a," "an," "the," and "said" include plural referents unless the content clearly dictates otherwise.

[0205] The terms "without", "not containing" and "not including" do not exclude impurities. Impurities have no technical influence on the purpose achieved by the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0206] These and / or other aspects and advantages of the present invention will become clear and more readily appreciated from the following description of exemplary embodiments taken in conjunction with the accompanying drawings, in which:

[0207] Figure 1 is a schematic diagram of a stacked layer structure of a tandem organic light emitting diode device;

[0208] Figure 2 is a schematic diagram of a stacked layer structure of another tandem organic light emitting diode device;

[0209] Figure 3 It is a schematic diagram of the stacked layer structure of another tandem organic light emitting diode device. DETAILED DESCRIPTION

[0210] Reference will now be made in detail to exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. The exemplary embodiments are described below, in order to explain aspects of the present invention, by referring to the drawings.

[0211] In this document, when a first element is referred to as being formed or disposed "on" a second element, the first element may be disposed directly on the second element, or one or more other elements may be disposed therebetween. When a first element is referred to as being formed or disposed "directly on" a second element, no other elements are disposed therebetween.

[0212] exist Figure 1 In the embodiment, a first hole injection layer 6, a first hole transport layer 7 and a first electron blocking layer 8 are provided between the anode 3 and the first light-emitting layer 9. A first electron transport layer 10 is provided between the first light-emitting layer 9 and the charge generation layer 5 (n-type sublayer 5a and p-type sublayer 5b). A second hole injection layer 11, a second hole transport layer 12 and a second electron blocking layer 13 are provided between the charge generation layer 5 and the second light-emitting layer 14. A second electron transport layer 15 is provided between the second light-emitting layer 14 and the cathode 4.

[0213] Figure 2 A schematic diagram of another tandem OLED is shown. In addition, the layer stack structure 1 provided on the substrate 2 further comprises an intermediate layer 16 between the n-type sublayer 5a and the p-type sublayer 5b.

[0214] Figure 3 A schematic diagram of another tandem OLED is shown. In the stacked layer structure 1 provided on the substrate 2, the n-type sublayer 5a of the charge generation layer 5 comprises a first n-type sublayer 5a1 and a second n-type sublayer 5a2. In an alternative embodiment (not shown), the charge generation layer 5 of the tandem OLED in FIG. 5 may include an intermediate layer 16.

[0215] Hereinafter, one or more exemplary embodiments of the present invention will be described in detail with reference to the following examples. However, these examples are not intended to limit the purpose and scope of the one or more exemplary embodiments of the present invention.

[0216] Example

[0217] First organic matrix compound

[0218] The first organic matrix compound is synthesized according to the steps disclosed in WO2016162440A1. The following compounds are used in the device examples of the present invention:

[0219]

[0220] Second organic matrix compound

[0221] The following compounds are used in the device examples of the present invention:

[0222]

[0223] Dopants in n-CGL

[0224] A first zero-valent metal dopant, wherein the first zero-valent metal dopant is selected from the group consisting of alkali metals, alkaline earth metals, rare earth metals, and Group 3 transition metals.

[0225] Ytterbium metal used as a dopant in device examples

[0226] Devices

[0227] General steps in making organic electronic devices

[0228] An organic electronic device was prepared to demonstrate the technical effect of an organic electronic device comprising a charge generation layer of the present invention. 2 A glass substrate (available from Corning) was cut into a size of 25 mm×25 mm×0.7 mm, and ultrasonically cleaned with isopropyl alcohol for 5 minutes, then with pure water for 5 minutes, and then with UV ozone for 30 minutes to prepare a first electrode. -7 The compositions and layer thicknesses are shown in Table 1. In Table 1, c refers to concentration and d refers to layer thickness.

[0229] Then, by -7 Aluminum is evaporated under ultra-high vacuum of 1000 mbar and an aluminum layer is directly deposited on the organic semiconductor layer to form a cathode electrode layer. ) to produce a homogeneous cathode electrode with a thickness of 5 to 1000 nm. The thickness of the cathode electrode layer is 100 nm.

[0230] The device is protected from environmental conditions by encapsulating the device with a glass slide, thereby forming a cavity which contains a getter material for further protection.

[0231] To evaluate the performance of the embodiments of the present invention compared to the prior art, the current efficiency was measured at ambient conditions (20° C.) The current voltage measurements were made using a Keithley 2400 source meter and recorded in V.

[0232] Table 1: Composition of organic electronic devices

[0233]

[0234]

[0235] Technical Effects of the Invention

[0236] The beneficial effects of the present invention on the performance of organic electronic devices can be seen in Tables 2 and 3. As can be seen from Table 2, compared with Comparative Examples 1, 2, and 3, the performance of the organic electronic devices of Examples 1, 3-5 of the present invention in terms of operating voltage and voltage increase over time is improved.

[0237]

[0238] General steps in making organic electronic devices

[0239] For bottom-emitting devices, Examples 6-9 and 2, 15Ω / cm with 90nm ITO 2 A glass substrate (available from Corning) was cut into a size of 50 mm×50 mm×0.7 mm, ultrasonically cleaned with isopropyl alcohol for 5 minutes, then ultrasonically cleaned with pure water for 5 minutes, and then cleaned with UV ozone for 30 minutes to prepare a first electrode.

[0240] Then, 97 vol% of biphenyl-4-yl(9,9-diphenyl-9H-fluoren-2-yl)-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-amine (CAS 1242056-42-3) and 3 vol% of 2,2′,2″-(cyclopropane-1,2,3-triylidene)tris(2-(p-cyanotetrafluorophenyl)acetonitrile) were vacuum deposited on the anode to form a HIL with a thickness of 10 nm.

[0241] Then, biphenyl-4-yl(9,9-diphenyl-9H-fluorene-2-yl)-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-amine was vacuum deposited on the HIL to form a first HTL with a thickness of 128 nm.

[0242] Then, N,N-bis(4-(dibenzo[b,d]furan-4-yl)phenyl)-[1,1':4',1"-terphenyl]-4-amine (CAS 1198399-61-9) was vacuum deposited on the HTL to form an electron blocking layer (EBL) with a thickness of 5 nm.

[0243] Then, 97 vol % of H09 (Sun Fine Chemicals, Korea) as an EML host and 3 vol % of BD200 (Sun Fine Chemicals, Korea) as a blue fluorescent dopant were deposited on the EBL to form a first blue light-emitting EML with a thickness of 20 nm.

[0244] Then, a first hole blocking layer was formed on the light emitting layer using 4′-(4-(4-(4,6-diphenyl-1,3,5-triazine-2-yl)phenyl)naphthalen-1-yl)-[1,1′-biphenyl]-4-carbonitrile with a thickness of 5 nm.

[0245] Then, an electron transport layer with a thickness of 25 nm was formed on the hole blocking layer by depositing 4'-(4-(4-(4,6-diphenyl-1,3,5-triazine-2-yl)phenyl)naphthalene-1-yl)-[1,1'-biphenyl]-4-carbonitrile. The electron transport layer (ETL) contained 50 wt% of a host compound and 50 wt% of LiQ.

[0246] Then, an n-CGL having a thickness of 15 nm was formed on the ETL. The n-CGL included a first organic compound, a second organic compound, and a metal dopant (Table 3). Then, a p-CGL having a thickness of 10 nm was formed on the n-CGL by depositing 90 volume % of biphenyl-4-yl(9,9-diphenyl-9H-fluorene-2-yl)-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-amine (CAS 1242056-42-3) and 10 volume % of 2,2',2"-(cyclopropane-1,2,3-triylidene)tris(2-(p-cyanotetrafluorophenyl)acetonitrile) on the n-CGL.

[0247] Then, biphenyl-4-yl(9,9-diphenyl-9H-fluorene-2-yl)-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-amine was vacuum deposited on the p-CGL to form a second HTL with a thickness of 10 nm.

[0248] In 10 -7 0.01 to mbar Al was evaporated at a rate of 100 nm to form a cathode with a thickness of 100 nm.

[0249] The OLED stack is protected from environmental conditions by encapsulating the device with a glass carrier, thereby forming a cavity which contains a getter material for further protection.

[0250] A tandem device stack structure comprising two light-emitting layers was fabricated in the same manner as described above. Table 3 describes the performance of the tandem device stack structure.

[0251]

Claims

1. An organic light-emitting device, comprising an anode, a cathode, at least two light-emitting layers, and at least one charge generation layer, wherein the at least two light-emitting layers are arranged between the anode and the cathode, and wherein the at least one charge generation layer is arranged between two of the at least two light-emitting layers; wherein the charge generation layer comprises an n-type sublayer and a p-type sublayer, Wherein the n-type sublayer comprises: a. at least one first organic compound, the first organic compound comprising at least one P=X group, wherein X is selected from O, S and Se; b. at least one second organic compound, said second organic compound comprising at least one metal complexing group; and c. A zero-valent metal dopant, wherein the zero-valent metal dopant is a metal selected from the group consisting of alkali metals, alkaline earth metals, rare earth metals, Group 3 transition metals, and mixtures thereof. 2 . The organic light emitting device according to claim 1 , wherein the charge generation layer further comprises an intermediate layer disposed between the n-type sublayer and the p-type sublayer. 3 . The organic light-emitting device according to claim 1 , wherein the first organic compound and / or the second organic compound comprises a conjugated system of at least 10 delocalized electrons.

4. The organic light-emitting device according to claim 1, wherein the first organic compound is represented by the following formula (I): wherein X is selected from O, S and Se; R 1 , R 2 and R 3 Independently selected from C1 to C 30 Alkyl, C3 to C 30 Cycloalkyl, C2 to C 30 Heteroalkyl, C6 to C 60 Aryl, C2 to C 50 Heteroaryl, C1 to C 30 Alkoxy, C3 to C 30 Cycloalkoxy, C6 to C 30 aryloxy; Where R 1 , R 2 and R 3 At least two of may be connected to each other to form a 5-, 6- or 7-membered ring together with the P atom, Where R 1 , R 2 and R 3 Each may independently contain one or more other groups: C6 to C 18 Aryl, C3 to C 20 heteroaryl, -PO(R')2, D, F or CN, C1 to C 16 Alkyl, C1 to C 16 Alkoxy, nitrile, wherein R' is phenyl and / or methyl, in, If R 1 , R 2 and R 3 If one or more of the carbon-containing groups is a carbon-containing group comprising at least one carbon atom directly connected to at least one hydrogen atom, the hydrogen atoms contained in the carbon-containing group may be partially or completely replaced by deuterium atoms and / or fluorine atoms.

5. The organic light emitting device according to claim 1, wherein R 1 , R 2 and R 3 At least one of the molecules comprises a conjugated system of at least 10 delocalized electrons.

6. The organic light emitting device according to claim 1, wherein R 1 , R 2 and R 3 At least one of them is phenyl, or R 1 , R 2 and R 3 At least one of the groups is a C1 to C4 alkyl group.

7. The organic light emitting device according to claim 4, wherein R 3 is selected from substituted or unsubstituted C6 to C 60 Aryl and C2 to C 50 Heteroaryl, where R 3 May independently contain one or more other groups: C6 to C 18 Aryl, C3 to C 20 heteroaryl, -PO(R')2, D, F or CN, C1 to C 16 Alkyl, C1 to C 16 Alkoxy, nitrile, wherein R' is phenyl and / or methyl, wherein if R 3 is a carbon-containing group comprising at least one carbon atom directly connected to at least one hydrogen atom, the hydrogen atoms contained in the carbon-containing group may be partially or completely replaced by deuterium atoms and / or fluorine atoms.

8. The organic light emitting device according to claim 1, wherein the first organic compound is one or more selected from the following compounds: 9 . The organic light-emitting device according to claim 1 , wherein the metal complexing group is a trivalent nitrogen atom.

10. The organic light-emitting device according to any one of claims 1 to 8, wherein the second organic compound comprises at least one metal complexing group, the metal complexing group comprising a C2 to C3 containing at least one nitrogen atom. 30 Heteroaryl groups. 11 . The organic light-emitting device according to claim 1 , wherein the second organic compound comprises at least one metal complexing group containing at least two nitrogen atoms.

12. The organic light emitting device according to any one of claims 1 to 8, wherein the second organic compound is one or more of the following compounds:

13. An organic light-emitting device according to claim 1, wherein the zero-valent metal dopant is selected from Li, Na, K, Rb, Cs, Mg, Ca, Sr, Ba, Yb, Sm, Eu, Nd, Tb, Gd, Ce, La, Sc and Y.

14. A method for manufacturing an organic light emitting device according to any one of the preceding claims, the method comprising the steps of: a1) evaporating the first organic compound and the second organic compound from different evaporation sources; or a2) co-evaporating the first organic compound and the second organic compound from the same evaporation source; and b) co-depositing the first organic compound and the second organic compound.

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