Organic light emitting diode and device including the same

Abstract

The invention relates to an organic light-emitting diode which comprises an anode, a cathode, a first light-emitting layer, a second light-emitting layer, a first charge generation layer and a first electron transport layer stacked layer. And a display device or a lighting device comprising the organic light emitting diode.

Description

Technical Field

[0001] The present invention relates to an organic light emitting diode and a device comprising the organic light emitting diode. Background of the Invention

[0003] Organic light emitting diodes (OLEDs), which are self-luminous devices, have wide viewing angles, excellent contrast, fast response, high brightness, excellent driving voltage characteristics, and color reproduction. A typical OLED includes an anode, a hole transport layer (HTL), an emitting layer (EML), an electron transport layer (ETL), and a cathode, which are sequentially stacked on a substrate. In this regard, the HTL, the EML, and the ETL are thin films formed of organic compounds and / or organometallic compounds.

[0004] When voltage is applied to the anode and cathode, holes injected from the anode move to the EML via the HTL, and electrons injected from the cathode 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.

[0005] A variety of organic light emitting diodes comprising different electron transport materials are known in the art. However, there is still a need to improve the performance of these devices, in particular of multi-emitting layer OLEDs, in particular with regard to driving voltage.

[0006] It is therefore an object of the present invention to provide an organic light emitting diode, in particular a multi-light emitting layer top emitting OLED with improved performance, which overcomes the disadvantages of the prior art, and has an improved driving voltage. Summary of the invention

[0007] The object is achieved by an organic light emitting diode, which comprises an anode, a cathode, a first light emitting layer, a second light emitting layer, a first charge generating layer and a first electron transport layer stack;

[0008] - the first charge generation layer is arranged between the first light-emitting layer and the second light-emitting layer;

[0009] - the first electron transport layer stack is arranged between the first light-emitting layer and the second light-emitting layer;

[0010] - the first electron transport layer stack comprises a first electron transport layer and a second electron transport layer;

[0011] - The first electron transport layer comprises a compound of formula (I):

[0012] (Ar 1-A c ) a -X b (I);

[0013] -a and b are independently 1 or 2;

[0014] -c is independently 0 or 1;

[0015] -Ar 1 Independently selected from C 6 To C 60 Aryl or C 2 To C 42 Heteroaryl,

[0016] - Each of Ar 1 may be substituted with one or two substituents independently selected from C 6 To C 12 Aryl, C 3 To C 11 Heteroaryl and C 1 To C 6 Alkyl, D, C 1 To C 6 Alkoxy, C 3 To C 6 Branched alkyl, C 3 To C 6 Cyclic alkyl, C 3 To C 6 Branched alkoxy, C 3 To C 6 Cyclic alkoxy, partially fluorinated or perfluorinated C 1 To C 6 Alkyl, partially fluorinated or perfluorinated C 1 To C 6 Alkoxy, partially deuterated or fully deuterated C 1 To C 6 Alkyl, partially deuterated or fully deuterated C 1 To C 6 Alkoxy, halogen, CN or PY(R 10 ) 2 , wherein Y is selected from O, S or Se, preferably O, and R 10 Independently selected from C 6 To C 12 Aryl, C 3 To C 12 Heteroaryl, C 1 To C 6 Alkyl, C 1 To C 6 Alkoxy, partially fluorinated or perfluorinated C 1 To C 6 Alkyl, partially fluorinated or perfluorinated C1 To C 6 Alkoxy, partially deuterated or fully deuterated C 1 To C 6 Alkyl, partially deuterated or fully deuterated C 1 To C 6 Alkoxy;

[0017] -Ar 1 Each C on 6 To C 12 Aryl Substituents and Ar 1 Each C on 3 To C 11 The heteroaryl substituent may be C 1 To C 4 Alkyl or halogen substituted;

[0018] -A is independently selected from C 6 To C 30 Aryl,

[0019] - wherein each A may be substituted with one or two substituents independently selected from C 6 To C 12 Aryl and C 1 To C 6 Alkyl, D, C 1 To C 6 Alkoxy, C 3 To C 6 Branched alkyl, C 3 To C 6 Cyclic alkyl, C 3 To C 6 Branched alkoxy, C 3 To C 6 Cyclic alkoxy, partially fluorinated or perfluorinated C 1 To C 6 Alkyl, partially fluorinated or perfluorinated C 1 To C 6 Alkoxy, partially deuterated or fully deuterated C 1 To C 6 Alkyl, partially deuterated or fully deuterated C 1 To C 6 Alkoxy, halogen, CN or PY(R 10 ) 2 , wherein Y is selected from O, S or Se, preferably O, and R 10 Independently selected from C 6 To C 12 Aryl, C 3 To C 12 Heteroaryl, C 1 To C 6 Alkyl, C 1 To C6 Alkoxy, partially fluorinated or perfluorinated C 1 To C 6 Alkyl, partially fluorinated or perfluorinated C 1 To C 6 Alkoxy, partially deuterated or fully deuterated C 1 To C 6 Alkyl, partially deuterated or fully deuterated C 1 To C 6 Alkoxy;

[0020] - where each C on A 6 To C 12 The aryl substituent may be C 1 To C 4 Alkyl or halogen substitution;

[0021] -X is independently selected from C 2 To C 42 Heteroaryl and C 6 To C 60 Aryl,

[0022] - wherein each X may be substituted with one or two substituents independently selected from C 6 To C 12 Aryl, C 3 To C 11 Heteroaryl and C 1 To C 6 Alkyl, D, C 1 To C 6 Alkoxy, C 3 To C 6 Branched alkyl, C 3 To C 6 Cyclic alkyl, C 3 To C 6 Branched alkoxy, C 3 To C 6 Cyclic alkoxy, partially fluorinated or perfluorinated C 1 To C 6 Alkyl, partially fluorinated or perfluorinated C 1 To C 6 Alkoxy, partially deuterated or fully deuterated C 1 To C 6 Alkyl, partially deuterated or fully deuterated C 1 To C 6 Alkoxy, halogen, CN or PY(R 10 ) 2 , wherein Y is selected from O, S or Se, preferably O, and R 10 Independently selected from C 6 To C 12 Aryl, C 3 To C12 Heteroaryl, C 1 To C 6 Alkyl, C 1 To C 6 Alkoxy, partially fluorinated or perfluorinated C 1 To C 6 Alkyl, partially fluorinated or perfluorinated C 1 To C 6 Alkoxy, partially deuterated or fully deuterated C 1 To C 6 Alkyl, partially deuterated or fully deuterated C 1 To C 6 Alkoxy;

[0023] - where each C on X 6 To C 12 The aryl substituent and each C 3 To C 11 The heteroaryl substituent may be C 1 To C 4 Alkyl or halogen substituted;

[0024] - the molecular dipole moment of the compound of formula (I) is ≥0D and ≤4D;

[0025] - The second electron transport layer comprises a compound of formula (II):

[0026] (Ar 2 ) m -(Z k -G) n (II);

[0027] - m and n are independently 1 or 2;

[0028] - k is independently 0, 1 or 2;

[0029] -Ar 2 Independently selected from C 2 To C 42 Heteroaryl and C 6 To C 60 Aryl,

[0030] - Each of Ar 2 may be substituted with one or two substituents independently selected from C 6 To C 12 Aryl, C 3 To C 11 Heteroaryl and C 1 To C 6 Alkyl, D, C 1 To C 6 Alkoxy, C 3 To C 6Branched alkyl, C 3 To C 6 Cyclic alkyl, C 3 To C 6 Branched alkoxy, C 3 To C 6 Cyclic alkoxy, partially fluorinated or perfluorinated C 1 To C 6 Alkyl, partially fluorinated or perfluorinated C 1 To C 6 Alkoxy, partially deuterated or fully deuterated C 1 To C 6 Alkyl, partially deuterated or fully deuterated C 1 To C 6 Alkoxy, halogen, CN or PY(R 10 ) 2 , wherein Y is selected from O, S or Se, preferably O, and R 10 Independently selected from C 6 To C 12 Aryl, C 3 To C 12 Heteroaryl, C 1 To C 6 Alkyl, C 1 To C 6 Alkoxy, partially fluorinated or perfluorinated C 1 To C 6 Alkyl, partially fluorinated or perfluorinated C 1 To C 6 Alkoxy, partially deuterated or fully deuterated C 1 To C 6 Alkyl, partially deuterated or fully deuterated C 1 To C 6 Alkoxy;

[0031] -Ar 2 Each C on 6 To C 12 Aryl Substituents and Ar 2 Each C on 3 To C 11 The heteroaryl substituent may be C 1 To C 4 Alkyl or halogen substituted;

[0032] -Z is independently selected from C 6 To C 30 Aryl,

[0033] - wherein each Z may be substituted with one or two substituents independently selected from C 6 To C 12 Aryl and C 1 To C6 Alkyl, D, C 1 To C 6 Alkoxy, C 3 To C 6 Branched alkyl, C 3 To C 6 Cyclic alkyl, C 3 To C 6 Branched alkoxy, C 3 To C 6 Cyclic alkoxy, partially fluorinated or perfluorinated C 1 To C 6 Alkyl, partially fluorinated or perfluorinated C 1 To C 6 Alkoxy, partially deuterated or fully deuterated C 1 To C 6 Alkyl, partially deuterated or fully deuterated C 1 To C 6 Alkoxy, halogen, CN or PY(R 10 ) 2 , wherein Y is selected from O, S or Se, preferably O, and R 10 Independently selected from C 6 To C 12 Aryl, C 3 To C 12 Heteroaryl, C 1 To C 6 Alkyl, C 1 To C 6 Alkoxy, partially fluorinated or perfluorinated C 1 To C 6 Alkyl, partially fluorinated or perfluorinated C 1 To C 6 Alkoxy, partially deuterated or fully deuterated C 1 To C 6 Alkyl, partially deuterated or fully deuterated C 1 To C 6 Alkoxy;

[0034] - where each C on Z 6 To C 12 The aryl substituent may be C 1 To C 4 Alkyl or halogen substitution;

[0035] -G is selected so that the dipole moment of the G-phenyl group of the compound is ≥1D and ≤7D;

[0036] - the first electron transport layer and the second electron transport layer do not contain electrical dopants;

[0037] - the first charge generation layer comprises a compound of formula (II), wherein the compound of formula (II) in the first charge generation layer is the same as the compound of formula (II) in the second electron transport layer; and

[0038] -G does not contain a P=O moiety.

[0039] The object is also achieved by a device comprising the organic light emitting diode of the present invention, wherein the device is a display device or a lighting device.

[0040] In the display device or the lighting device, light may be emitted through the transparent cathode.

[0041] In the display device or the lighting device, light may be emitted through the transparent anode.

[0042] First electron transport layer

[0043] The first electron transport layer comprises a compound of formula (I):

[0044] (Ar 1 -A c ) a -X b (I).

[0045] The first electron transport layer may consist of the compound of formula (I). Alternatively, the first electron transport layer may consist of a mixture of the compound of formula (I) and one or more other compounds, provided that none of the other compounds is an electrical dopant. The first electron transport layer may contain more than one compound of formula (I). In particular, the first electron transport layer may consist of a mixture of the compound of formula (I) and other compounds known in the art as electron transport matrix compounds. Exemplary other electron transport matrix compounds that may be contained are disclosed below.

[0046] In the compounds of formula (I), the group "A" is a linker (if present, i.e. in the case of c>1) to the group Ar 1 and the spacer moiety of X. In the case where the compound of formula (I) contains more than one group (Ar 1 -A c ), the group may or may not independently contain a spacer group A.

[0047] In the compound of formula (I), a and b are independently 1 or 2. Alternatively, a and b may both be 1.

[0048] In the compound of formula (I), c is independently 0 or 1.

[0049] Ar 1 Independently selected from C 6 To C60 Aryl or C 2 To C 42 Heteroaryl, or C 6 To C 54 Aryl or C 2 To C 39 Heteroaryl, or C 6 To C 48 Aryl or C 2 To C 36 Heteroaryl, or C 6 To C 42 Aryl or C 2 To C 36 Heteroaryl, or C 6 To C 36 Aryl or C 2 To C 30 Heteroaryl, or C 6 To C 30 Aryl or C 2 To C 24 Heteroaryl.

[0050] Ar 1 Can be independently C 6 To C 54 Aryl, optionally C 6 To C 48 Aryl, optionally C 6 To C 42 Aryl, optionally C 6 To C 36 Aryl, optionally C 6 To C 30 Aryl, optionally C 6 To C 24 Aryl.

[0051] Ar 1 Can be independently C 2 To C 42 Heteroaryl, optionally C 2 To C 40 Heteroaryl, optionally C 2 To C 36 Heteroaryl, optionally C 2 To C 30 Heteroaryl, optionally C 2 To C 24 Heteroaryl.

[0052] In one embodiment, Ar 1 Different from X.

[0053] Ar 1 The system may contain two or more fused aromatic rings, preferably three or more fused aromatic rings.

[0054] Ar 1 Can contain at least one sp 3 Hybridized carbon atoms.

[0055] Ar 1 may contain at least one carbon-carbon sp not incorporated into the aromatic ring structure 2 Olefin bonds.

[0056] In one embodiment, wherein Ar 1 Independently selected from unsubstituted C 2 To C 42 Heteroaryl, the heteroatom is bonded to Ar by a single bond 1 in the molecular structure.

[0057] Ar 1 The phenyl group may be independently selected from phenyl, naphthyl, anthracenyl, fluoranthenyl, xanthene, dibenzofuranyl, pyrimidinyl, pyrazinyl, spiroxanthenyl, fluorenyl, spirofluorenyl, triphenylsilyl, tetraphenylsilyl, or a group having formula (IIa) or (IIb):

[0058]

[0059] in

[0060] - the asterisk symbol "*" indicates the binding position of the group of formula (IIa) to A; and

[0061] -R 1 To R 9 Independently selected from H, C 6 To C 12 Aryl and C 4 To C 10 Heteroaryl.

[0062] In the group of formula (IIa), R 6 and R 7 and / or R 8 and R 9 All may be phenyl.

[0063] If Ar 1 is a group having formula (IIb), the group having formula (IIb) can be combined with A (or with X in the absence of A, i.e., c=0) through the group R 6 To R 9 , wherein A (respectively, X) (formally) replaces the corresponding R 6 To R 9 The terminal hydrogen atom.

[0064] Ar 1may be independently selected from fluoranthenyl, dibenzofuranyl, pyrimidinyl, pyrazinyl, 9,9-dimethylfluorenyl, a group having formula (IIa), a group having formula (IIb),

[0065]

[0066] in

[0067] - the asterisk symbol "*" indicates the binding position of the group of formula (IIa) to A; and

[0068] -R 1 is H, and R 2 To R 5 are independently phenyl; or

[0069] -R 1 and R 3 is phenyl, and R 2 , R 4 and R 5 is H; or

[0070] -R 6 To R 9 It is phenyl.

[0071] If Ar 1 is a group having formula (IIb), the group having formula (IIb) can be combined with A (or with X in the absence of A, i.e., c=0) through the group R 6 To R 9 , wherein A (respectively, X) (formally) replaces the corresponding R 6 To R 9 The terminal hydrogen atom.

[0072] In the group of formula (IIa), R 1 To R 5 At least two non-H groups in R may be in ortho positions to each other. 1 To R 5 At least one non-H group in may be in an ortho position to the * position. In this regard, if two groups are respectively bound to adjacent carbon atoms of the benzene ring in formula (IIa), they are in ortho positions to each other. In other words, it can be specified that R 1 and R 5 At least one of them is phenyl; and / or R 1 and R 2 are phenyl; and / or R 2 and R 3 are phenyl; and / or R 3 and R 4 are phenyl; and / or R 4 and R5 They are all phenyl.

[0073] Ar 1 Can be independently selected from one of the following groups:

[0074]

[0075] The asterisk symbol "*" indicates the binding position to A, and can be substituted or unsubstituted.

[0076] In Ar 1 Where substituted, each substituent may be independently selected from phenyl, naphthyl, biphenyl, pyridyl, picolinyl, dipicolinyl, dibenzofuranyl, dibenzothienyl and benzothienyl.

[0077] A may be independently selected from phenylene, naphthylene, biphenylene and terphenylene, each of which may be substituted or unsubstituted.

[0078] A can be independently selected from one or a combination of the following groups:

[0079]

[0080] Among them, Ar 1 The binding position of X can be freely selected, preferably

[0081]

[0082] In the case where A is substituted, each substituent on A may be independently selected from phenyl and C 1 To C 4 alkyl.

[0083] X can be independently selected from C 2 To C 39 Heteroaryl and C 6 To C 54 Aryl, optionally selected from C 2 To C 36 Heteroaryl and C 6 To C 48 Aryl, optionally selected from C 3 To C 30 Heteroaryl and C 6 To C 42 Aryl, optionally selected from C 3 To C 27 Heteroaryl and C 6 To C 36 Aryl, optionally selected from C 3 To C 24 Heteroaryl and C 6 To C 30 Aryl, optionally selected from C3 To C 21 Heteroaryl and C 6 To C 24 Aryl, wherein the corresponding radical may be substituted or unsubstituted.

[0084] X can be independently selected from C 2 To C 39 Containing N heteroaryl, C 2 To C 39 Containing O heteroaryl and C 6 To C 54 Aryl, optionally selected from C 2 To C 36 Containing N heteroaryl, C 2 To C 36 Containing O heteroaryl and C 6 To C 48 Aryl, optionally selected from C 3 To C 30 Containing N heteroaryl, C 3 To C 30 Containing O heteroaryl and C 6 To C 42 Aryl, optionally selected from C 3 To C 27 Containing N heteroaryl, C 3 To C 27 Containing O heteroaryl and C 6 To C 36 Aryl, optionally selected from C 3 To C 24 Containing N heteroaryl, C 3 To C 24 Containing O heteroaryl and C 6 To C 30 Aryl, optionally selected from C 3 To C 21 Containing N heteroaryl, C 3 To C 21 Containing O heteroaryl and C 6 To C 24 Aryl.

[0085] X can be independently selected from C 2 To C 39 Containing N heteroaryl and C 6 To C 54 Aryl, optionally selected from C 2 To C 36 Containing N heteroaryl and C 6 To C 48 Aryl, optionally selected from C 3 To C 30 Containing N heteroaryl and C 6 To C 42 Aryl, optionally selected from C3 To C 27 Containing N heteroaryl and C 6 To C 36 Aryl, optionally selected from C 3 To C 24 Containing N heteroaryl and C 6 To C 30 Aryl, optionally selected from C 3 To C 21 Containing N heteroaryl and C 6 To C 24 In this context, it can be provided that the corresponding N-containing heteroaryl radicals contain one or more N atoms as the only heteroatoms.

[0086] X may be independently selected from triazine, 1,2-diazine, 1,3-diazine, 1,4-diazine, quinazolinyl, benzoquinazolinyl, benzimidazolyl, quinolinyl, benzoquinolinyl, benzoacridinyl, dibenzoacridinyl, fluoranthenyl, anthracenyl, naphthyl, terphenylidene, phenanthrolinyl and dinaphthofuranyl, each of which may be substituted or unsubstituted.

[0087] X may be independently selected from triazine, 1,2-diazine, 1,3-diazine, 1,4-diazine, quinazolinyl, benzoquinazolinyl, benzoacridinyl, dibenzoacridinyl, fluoranthenyl, anthracenyl, naphthyl, terphenylidene, phenanthrolinyl and dinaphthofuranyl, each of which may be substituted or unsubstituted.

[0088] X may be independently selected from triazine, 1,2-diazine, 1,3-diazine, 1,4-diazine, quinazolinyl, benzoquinazolinyl, benzoacridinyl, dibenzoacridinyl, fluoranthenyl, each of which may be substituted or unsubstituted.

[0089] X can be independently selected from one of the following groups:

[0090]

[0091] The asterisk symbol "*" represents the binding position of the group to A.

[0092] In the case where X is substituted, each substituent on X may be independently selected from phenyl, naphthyl, and biphenyl. In the case where X is substituted, each substituent on X may be independently selected from phenyl and biphenyl.

[0093] In the case where X is substituted, the corresponding substituted X group may be

[0095] Wherein the asterisk symbol "*" represents the binding position of the group to A. X (including substituents) can be independently selected from one of the following groups:

[0096]

[0097]

[0098] The asterisk symbol "*" represents the combination with A (in the case of c = 0, with Ar 1 ) binding position.

[0099] It may be provided that the compound of formula (I) does not contain a P=O moiety. It may be provided that the compound of formula (I) does not contain a P(=O) aromatic group. 2 It may be provided that the compound of formula (I) does not contain a P(=O)alkyl group. 2 It may be provided that the compound of formula (I) does not contain P(=O)Ph 2 It may be provided that the compound of formula (I) does not contain P(═O)(CH 3 ) 2 It may be provided that the compound of formula (I) does not contain R'P(=O)R", wherein R' and R" are linked to each other to form a ring, i.e., does not contain cyclic phosphine oxide. It may be provided that the compound of formula (I) does not contain R'P(=O)R", wherein R' and R" are linked to each other to form a 7-membered ring.

[0100] It may be provided that the compound of formula (I) does not contain two moieties P=O. It may be provided that the compound of formula (I) does not contain two P(=O) aromatic groups 2 It may be provided that the compound of formula (I) does not contain two P(=O)alkyl 2 It may be provided that the compound of formula (I) does not contain two P(=O)Ph 2 It may be provided that the compound of formula (I) does not contain two P(=O)(CH 3 ) 2 It may be provided that the compound of formula (I) contains no CN.

[0101] It may be specified that one or more of the following formulae are excluded from the scope of compounds of formula (I):

[0102]

[0103]

[0104] The compound of formula (I) may comprise 6 to 14 aromatic or heteroaromatic rings, optionally 7 to 13 aromatic or heteroaromatic rings, optionally 7 to 12 aromatic or heteroaromatic rings, optionally 9 to 11 aromatic or heteroaromatic rings. In this regard, the aromatic or heteroaromatic rings are respectively single aromatic rings, for example 6-membered aromatic rings such as phenyl, 6-membered heteroaromatic rings such as pyridyl, 5-membered heteroaromatic rings such as pyrrolyl etc. In this regard, in fused (hetero) aromatic ring systems, each ring is considered as a monocycle. For example, naphthalene comprises two aromatic rings.

[0105] The molecular dipole moment of the compound of formula (I) calculated by TURBOMOLE V6.5 program package using hybrid functional B3LYP and Gaussian6-31G* basis set may be ≥0D and ≤4D; or ≥0D and ≤3.5D; or ≥0D and ≤3.0D; or ≥0D and ≤2.5D; or ≥0D and ≤2.0D. In this regard, the dipole moment of the molecule containing N atoms is It is derived from the following formula:

[0106]

[0107] where q i and is the partial charge and position of atom i in the molecule. The dipole moment is determined by the semi-empirical molecular orbital method. The geometry of the molecular structure is optimized in the gas phase using the hybrid functional B3LYP with the 6-31G* basis set as implemented in the program package TURBOMOLE V6.5 (TURBOMOLE Co., Ltd., Litzenhardtstrasse 19, 76135 Karlsruhe, Germany). If more than one conformation is feasible, the conformation with the lowest total energy is selected to determine the bond length of the molecule.

[0108] In one embodiment, at an absolute scale with the vacuum energy level as zero, the LUMO energy level of the compound of formula (I) calculated by the TURBOMOLE V6.5 program package using the hybrid functional B3LYP and the Gaussian 6-31G* basis set is in the range of -1.90 eV to -1.60 eV, preferably -1.87 eV to -1.65 eV, and preferably -1.85 eV to -1.65 eV.

[0109] The compound of formula (I) may be selected from compounds A-1 to A-41 in Table 1 below.

[0110] Table 1:

[0111]

[0112]

[0113]

[0114]

[0115]

[0116]

[0117]

[0118]

[0119] In one embodiment, at an absolute scale with the vacuum energy level as zero, the LUMO energy level of the compound of formula (I) calculated by the TURBOMOLE V6.5 program package using the hybrid functional B3LYP and the Gaussian 6-31G* basis set is in the range of -1.90 eV to -1.45 eV, preferably -1.89 eV to -1.47 eV.

[0120] The first electron transport layer may be arranged between the light-emitting layer and the second electron transport layer. The first electron transport layer may be arranged to be in direct contact with the light-emitting layer. The first electron transport layer may be arranged to be "contact-sandwiched" between the light-emitting layer and the second electron transport layer.

[0121] The thickness of the first electron transport layer may be <50 nm, optionally between 1 and 30 nm, optionally between 1 and 10 nm, optionally between 1 and 5 nm.

[0122] Second electron transport layer

[0123] The second electron transport layer comprises a compound of formula (II):

[0124] (Ar 2 ) m -(Z k -G) n (II).

[0125] The second electron transport layer may be composed of the compound of formula (II). Alternatively, the second electron transport layer may be composed of a mixture of the compound of formula (II) and one or more other compounds, provided that none of the other compounds is an electrical dopant. The first electron transport layer may contain more than one compound of formula (II). The second electron transport layer may be composed of a mixture of the compound of formula (II) and other compounds known in the art as electron transport matrix compounds. Exemplary other electron transport matrix compounds that may be contained are disclosed below.

[0126] G does not contain a P=O moiety. The term "does not contain a P=O moiety" refers in particular to phosphine oxides and generally to all compounds in which a P=O group is bonded to three other groups via a single bond to the P atom. For example, a P=O moiety can be an oxyphosphinyl group (P(=O)R) bonded to Z via a single bond or via any organic divalent group. 2 ). "Not containing" means that the corresponding part is not part of the structure of the group G.

[0127] It may be provided that the compound of formula (II) does not contain a P=O moiety. It may be provided that the compound of formula (II) does not contain a P(=O) aromatic group. 2 It may be provided that the compound of formula (II) does not contain a P(=O)alkyl group. 2 It may be provided that the compound of formula (II) does not contain P(=O)Ph 2 It may be provided that the compound of formula (II) does not contain P(═O)(CH 3 ) 2 It may be provided that the compound of formula (II) does not contain R'P(=O)R", wherein R' and R" are connected to each other to form a ring, i.e., does not contain cyclic phosphine oxide. It may be provided that the compound of formula (II) does not contain R'P(=O)R", wherein R' and R" are connected to each other to form a 7-membered ring.

[0128] It may be provided that the compound of formula (II) does not contain two moieties P=O. It may be provided that the compound of formula (II) does not contain two P(=O) aromatic groups 2 It may be provided that the compound of formula (II) does not contain two P(=O)alkyl groups. 2 It may be provided that the compound of formula (II) does not contain two P(=O)Ph 2 It may be provided that the compound of formula (II) does not contain two P(═O)(CH 3 ) 2 .

[0129] It may be specified that one or more of the following formulae are excluded from the scope of compounds of formula (II):

[0130]

[0131]

[0132] In the compounds of formula (II), the group "Z" is a linker (if present, i.e. in the case of k>1) to the group Ar 2 and the spacer portion of G. In the case where the compound of formula (II) contains more than one group (Z k In the case of -G), the group may or may not independently contain a spacer group Z.

[0133] In formula (II), m and n are independently 1 or 2. In formula (II), m and n may be 1.

[0134] In formula (II), k is independently 0, 1 or 2. In formula (II), k may be independently 1 or 2.

[0135] Ar 2 Can be independently selected from C 2 To C 39 Heteroaryl and C 6 To C 54 Aryl, optionally selected from C 2 To C 36 Heteroaryl and C 6 To C 48 Aryl, optionally selected from C 3 To C 30 Heteroaryl and C 6 To C 42 Aryl, optionally selected from C 3 To C 27 Heteroaryl and C 6 To C 36 Aryl, optionally selected from C 3 To C 24 Heteroaryl and C 6 To C 30 Aryl, optionally selected from C 3 To C 21 Heteroaryl and C 6 To C 24 Aryl.

[0136] Ar 2 Can be independently selected from C 2 To C 39 Containing N heteroaryl and C 6 To C 54 Aryl, optionally selected from C 2 To C 36 Containing N heteroaryl and C 6 To C 48 Aryl, optionally selected from C 3 To C 30 Containing N heteroaryl and C 6 To C 42 Aryl, optionally selected from C 3 To C 27 Containing N heteroaryl and C 6 To C 36 Aryl, optionally selected from C 3 To C 24 Containing N heteroaryl and C 6 To C 30 Aryl, optionally selected from C 3 To C 21Containing N heteroaryl and C 6 To C 24 In this context, it can be provided that the corresponding N-containing heteroaryl radicals contain one or more N atoms as the only heteroatoms.

[0137] Ar 2 It may contain at least two fused 5-membered or 6-membered rings.

[0138] Ar 2 The benzophenone group may be independently selected from pyridyl, triazine, 1,2-diazine, 1,3-diazine, 1,4-diazine, quinazolinyl, benzoquinazolinyl, benzimidazolyl, quinolinyl, benzoquinolinyl, benzoacridinyl, dibenzoacridinyl, fluoranthenyl, anthracenyl, naphthyl, terphenylidene, phenanthrolinyl and dinaphthofuranyl, each of which may be substituted or unsubstituted.

[0139] Ar 2 The group may be independently selected from 1,3-diazinyl, 1,4-diazinyl, anthracenyl, triazinyl, dibenzoacridinyl and phenanthroline, each of which may be substituted or unsubstituted.

[0140] Ar 2 Can be independently selected from one of the following groups:

[0141]

[0142] The asterisk symbol "*" indicates the binding position of Z.

[0143] In Ar 2 When substituted, Ar 2 Each substituent on may be independently selected from phenyl, naphthyl, optional β-naphthyl, pyridyl and biphenyl, each of which may be substituted or unsubstituted.

[0144] In Ar 2 When substituted, Ar 2 Each substituent on may be a phenyl group.

[0145] Ar 2 (including all substituents) may be selected from:

[0146]

[0147] The asterisk symbol "*" indicates the binding position of Z.

[0148] Z can be independently selected from C 6 To C 30 Aryl, alternatively selected from C 6 To C 24 Aryl, alternatively selected from C 6 To C 18Aryl, alternatively selected from C 6 To C 12 , which may be substituted or unsubstituted.

[0149] Z may be selected from phenylene, naphthylene, phenylene-naphthylene, phenylene-naphthylene-phenylene, phenylene-anthracenylene-phenylene, biphenylene and terphenylene, each of which may be substituted or unsubstituted.

[0150] Z may be selected from phenylene, phenylene-naphthylene, biphenylene and terphenylene, each of which may be substituted or unsubstituted.

[0151] Z can be independently selected from one of the following groups:

[0152]

[0153] Among them, Ar 2 The binding position with G can be freely selected.

[0154] Z can be independently selected from one of the following groups:

[0155]

[0156] Among them, Ar 2 The binding position with G can be freely selected.

[0157] In the case where Z is substituted, each substituent on Z may be independently selected from phenyl and C 1 To C 4 alkyl.

[0158] G is selected so that the dipole moment of the compound G-phenyl calculated by the TURBOMOLE V6.5 program package, using the hybrid functional B3LYP and Gaussian 6-31G* basis set is ≥1D and ≤7D. The unit of dipole moment "Debye" is abbreviated as the symbol "D". The inventors have found that it is advantageous if the compound of formula (II) contains a group having a certain polarity, i.e., a specific dipole moment within the above range or the following range. It is also found that if the compound of formula (II) further contains another polar group (second polar group) suitable for balancing the dipole moment of the first polar group in a manner that makes the total dipole moment of the compound of formula (II) lower, it is still advantageous for the compound of formula (II) to contain such a polar group (first polar group), for example, in the case where the compound is a symmetrical molecule containing the same first polar group and second polar group, the dipole moment can be 0 Debye. Therefore, the compound of formula (II) cannot be characterized by the total dipole moment of the compound. Therefore, as an alternative, reference is made to a mimetic compound comprising a polar group "G" and a nonpolar group "phenyl". In this context, the dipole moment of the compound containing the N atom is It is derived from the following formula:

[0159]

[0160] where q i and is the partial charge and position of atom i in the molecule. The dipole moment is determined by the semi-empirical molecular orbital method. The geometry of the molecular structure is optimized in the gas phase using the hybrid functional B3LYP and 6-31G* basis set as implemented in the program package TURBOMOLE V6.5 (TURBOMOLE Co., Ltd., Litzenhardtstrasse 19, 76135Karlsruhe, Germany). If more than one conformation is feasible, the conformation with the lowest total energy is selected to determine the bond length of the molecule. In this regard, the entire part G covers all feasible substituents that can be included.

[0161] G may be selected such that the dipole moment of compound G-phenyl is >1 D; optionally ≥1.1 D; optionally ≥1.14 D. G may be selected such that the dipole moment of compound G-phenyl is ≤7 D, optionally ≤6.5 D, optionally ≤6 D, optionally ≤5.7 D, optionally ≤5.63 D.

[0162] In one embodiment, the dipole moment of compound G-phenyl is ≥1D and ≤6D; optionally ≥1.1D and ≤5.7D.

[0163] If the compound G-phenyl has more than one conformer, the average value of the dipole moments of the conformers of G-phenyl is selected to be within this range.Conformers are stereoisomeric forms in which isomers can be interconverted solely by formal rotation about single bonds.

[0164] By selecting G so that the dipole moment of the compound G-phenyl is within the above range, the electron injection of adjacent different charge generation layers (CGL) can be improved, the voltage of the OLED device can be reduced, and the cd / A efficiency of the OLED device can be improved.

[0165] The following lists exemplary compounds "G-phenyl", wherein the corresponding part of the compound

[0166]

[0167] Indicates "G- Phenyl The "phenyl" part of

[0168]

[0169]

[0170]

[0171] Table 2:

[0172]

[0173]

[0174]

[0175]

[0176]

[0177]

[0178]

[0179] G can be selected from nitrile, benzonitrile, nicotinonitrile, amide, carbamide and C 2 To C 42 Heteroaryl; wherein G may include one or more substituents attached to the group, wherein the one or more substituents are selected from C 6 To C 18 Aryl, C 1 To C 10 Alkyl, C 2 To C 14 Heteroaryl.

[0180] G can be selected from C 2 To C 39 Heteroaryl, optionally selected from C 2 To C 35 Heteroaryl, optionally selected from C 2 To C 32 Heteroaryl, optionally selected from C 2 To C 29 Heteroaryl, optionally selected from C 2 To C 25 Heteroaryl; G may include one or more substituents attached to the group, wherein the one or more substituents are selected from C 6 To C 12 Aryl, C 1 To C 6 Alkyl, C 2 To C 11 Heteroaryl.

[0181] G can be selected from C 2 To C 25 Heteroaryl; wherein the corresponding G may include one or more substituents attached to the group, wherein the one or more substituents are selected from C 6 To C 10Aryl, C 1 To C 4 Alkyl, C 2 To C 5 Heteroaryl.

[0182] G can be selected from nitrile, benzonitrile, nicotinonitrile, amide, carbamide and C 2 To C 17 Heteroaryl; wherein the corresponding G may include one or more substituents attached to the group, wherein the one or more substituents are selected from phenyl, methyl, ethyl and pyridyl.

[0183] G may be selected from phenanthroline, 2,2'-bipyridyl, 9-phenyl-1,10-phenanthroline, 1,10-phenanthroline, (pyridin-2-yl)imidazo[1,5-a]pyridinyl, 2-pyridin-2-ylquinolyl, terpyridyl, nitrile, benzonitrile, nicotinonitrile, dihydrobenzimidazolone, diphenylpropyl, N,N-dimethylacetamide, amide, carbamide, imidazolyl, phenylbenzimidazolyl, ethylbenzimidazolyl, phenylbenzoquinolyl, phenylbenzimidazolyl, pyridyl, bipyridyl, methylpyridyl, dimethylpyridyl, pyridazinyl, pyrimidinyl, pyrazinyl, triphenylpyrazinyl, benzoquinolyl, phenanthroline, phenylphenanthroline quinazoline, benzo oxazolyl, benzimidazolylpyridinylimidazopyridinyl;

[0184]

[0185] The asterisk symbol "*" indicates the binding position.

[0186] G may be selected from phenanthrolinyl, 2,2'-bipyridyl, 9-phenyl-1,10-phenanthrolinyl, 1,10-phenanthrolinyl, (pyridin-2-yl)imidazo[1,5-a]pyridinyl and 2-pyridin-2-yl-quinolinyl.

[0187] The compound of formula (II) may comprise 6 to 12 aromatic or heteroaromatic rings, optionally 6 to 11 aromatic or heteroaromatic rings, optionally 7 to 10 aromatic or heteroaromatic rings, optionally 7 to 9 aromatic or heteroaromatic rings. In this regard, the aromatic or heteroaromatic rings are respectively single aromatic rings, for example 6-membered aromatic rings such as phenyl, 6-membered heteroaromatic rings such as pyridyl, 5-membered heteroaromatic rings such as pyrrolyl etc. In this regard, in fused (hetero) aromatic ring systems, each ring is considered as a monocyclic ring. For example, naphthalene comprises two aromatic rings.

[0188] The compound of formula (II) may be selected from compounds B-1 to B-27 and / or compounds shown in Table 3.

[0189]

[0190]

[0191]

[0192]

[0193] Table 3 summarizes exemplary compounds of formula (II) and their properties.

[0194] Table 3:

[0195]

[0196]

[0197]

[0198]

[0199]

[0200]

[0201] In one embodiment, the LUMO energy level of the compound of formula (II) calculated by the TURBOMOLE V6.5 program package using the hybrid functional B3LYP and the Gaussian 6-31G* basis set at an absolute scale with the vacuum energy level as zero is in the range of -2.30 eV to -1.20 eV, preferably -2.00 eV to -1.55 eV, and preferably -1.96 eV to -1.61 eV.

[0202] In one embodiment, the compound of formula (II) comprises a polar group "G".

[0203] The second electron transport layer may further comprise compound (III), wherein the compound (III) comprises 8 to 13 aromatic or heteroaromatic rings, optionally 8 to 11 aromatic or heteroaromatic rings, optionally 9 to 11 aromatic or heteroaromatic rings, optionally 9 aromatic or heteroaromatic rings, wherein one or more aromatic or heteroaromatic rings may be C 1 To C 4 In this context, an aromatic or heteroaromatic ring is a single aromatic ring, for example a 6-membered aromatic ring such as phenyl, a 6-membered heteroaromatic ring such as pyridyl, a 5-membered heteroaromatic ring such as pyrrolyl, etc. In this context, in a fused (hetero)aromatic ring system, each ring is considered a single ring. For example, naphthalene contains two aromatic rings.

[0204] The compound (III) may contain at least one heteroaromatic ring, optionally 1 to 5 heteroaromatic rings, optionally 1 to 4 heteroaromatic rings, optionally 1 to 3 heteroaromatic rings, optionally 1 or 2 heteroaromatic rings.

[0205] The aromatic or heteroaromatic ring of the compound (III) may be a 6-membered ring.

[0206] The heteroaromatic rings of the compound (III) may be N-containing heteroaromatic rings, optionally all heteroaromatic rings are N-containing heteroaromatic rings, optionally all heteroaromatic rings contain N as the only heteroatom type.

[0207] The compound (III) may contain at least one 6-membered heteroaromatic ring containing one to three N atoms in each heteroaromatic ring, and optionally contain one to three 6-membered heteroaromatic rings containing one to three N atoms in each heteroaromatic ring.

[0208] The at least one 6-membered heteroaromatic ring contained in the compound (III) may be an azine. The at least one 6-membered heteroaromatic ring contained in the compound (III) may be a triazine, a diazine, or a pyrazine.

[0209] If the compound (III) contains two or more heteroaromatic rings, the heteroaromatic rings may be separated from one another by at least one aromatic ring which does not contain heteroatoms.

[0210] In one embodiment, the heteroatom in the heteroaromatic ring of compound (III) is bonded to the molecular structure of compound (III) via at least one double bond.

[0211] The molecular dipole moment of the compound (III) calculated by TURBOMOLE V6.5 program package using hybrid functional B3LYP and Gaussian6-31G* basis set may be ≥0D and ≤4D; or ≥0.1D and ≤3.9D; or ≥0.2D and ≤3.7D; or ≥0.3D and ≤3.5D.

[0212] By selecting compound (III) according to these embodiments, the mobility of the second electron transport layer can be further improved, the voltage of the OLED device can be reduced, and the cd / A efficiency of the OLED device can be increased.

[0213] In one embodiment, the compound (III) is not a compound of formula (II). The compound of formula (III) may be selected from compounds C-1 to C-6 in Table 4 below.

[0214] Table 4:

[0215]

[0216]

[0217] When the second electron transport layer comprises a compound of formula (II) and compound (III), the weight ratio of formula (II) to compound (III) can be 1:99 to 99:1, or 10:90 to 60:40, or 20:80 to 50:50, or 25:75 to 40:60, or about 30:70.

[0218] In one embodiment, the LUMO energy level of compound (III) calculated by TURBOMOLE V6.5 program package using hybrid functional B3LYP and Gaussian 6-31G* basis set at an absolute scale with vacuum level as zero is in the range of -2.00 eV to -1.70 eV, preferably -1.95 eV to -1.80 eV.

[0219] In one embodiment, the compound (III) comprises a nitrogen-containing six-membered ring.

[0220] In another embodiment, the compound (III) comprises two nitrogen-containing six-membered rings.

[0221] In one embodiment, the compound of formula (I) is not a compound of formula (II). In another embodiment, the compound of formula (II) is not compound (III). In another embodiment, the compound of formula (I) is not compound (III). In another embodiment of the present invention, all three compounds, i.e., the compound of formula (I), the compound of formula (II) and compound (III) differ from each other in that they have different molecular structural formulas.

[0222] The second electron transport layer may be arranged between the first electron transport layer and the electron injection layer. The second electron transport layer may be arranged to be in direct contact with the first electron transport layer. The second electron transport layer may be arranged to be in direct contact with the electron injection layer. The second electron transport layer may be arranged to be in direct contact with the cathode.

[0223] The second electron transport layer may be arranged to be “contact-sandwiched” between the first electron transport layer and the electron injection layer.

[0224] The second electron transport layer may be arranged between the first electron transport layer and the charge generation layer. The second electron transport layer may be arranged to be in direct contact with the charge generation layer. The second electron transport layer may be arranged to be in direct contact with the n-type CGL.

[0225] The second electron transport layer may be arranged to be “contact-sandwiched” between the first electron transport layer and the n-type CGL.

[0226] The thickness of the second electron transport layer may be <100 nm, optionally between 10 and 90 nm, optionally between 10 and 60 nm, optionally between 10 and 50 nm.

[0227] First charge generation layer

[0228] The first charge generation layer is arranged between the first light-emitting layer and the second light-emitting layer. The first charge generation layer comprises a compound of formula (II), wherein the compound of formula (II) in the first charge generation layer is the same as the compound of formula (II) in the second electron transport layer. That is, a specific compound of formula (II) is selected for use in the first charge generation layer, and then the same specific compound of formula (II) is also used in the second electron transport layer as the compound of formula (II). In other words, "the same compound" in this regard refers to a compound having the same chemical formula, including the same isomers.

[0229] The second electron transport layer may be arranged to be in direct contact with the first charge generation layer. The charge generation layer may include a p-type sublayer and an n-type sublayer, and the second electron transport layer may be in direct contact with the n-type sublayer. An intermediate layer may be arranged between the p-type layer and the n-type layer. The intermediate layer may be in direct contact with the p-type layer or the n-type layer. The intermediate layer may be in direct contact with the p-type layer and the n-type layer.

[0230] The first electron transport layer stack may be disposed between the first light emitting layer and the first charge generating layer.

[0231] The first charge generation layer comprises a metal or an alkali metal, a metal salt or an alkaline earth metal salt and / or a rare earth metal salt, or an organic alkali metal complex or an alkali metal complex, or LiF, LiCl, LiBr, LiI, LiQ, a metal borate or a mixture thereof. The metal cation of the metal salt may be selected from alkali metals, alkaline earth metals and rare earth metals, or from Li, Na, K, Rb, Cs, Mg, Ca, Sr and Ba; or from Li, Mg, Ca and Sr. The anion of the metal salt may be selected from quinoline, phosphine oxide phenolate and borate. For example, corresponding compounds are disclosed in EP1837926A1, WO07107306A1 or WO07107356A1.

[0232] The thickness of the first charge generation layer may be in the range of 5 to 20 nm, in particular 10 to 20 nm, such as about 15 nm.

[0233] Other Viable Properties of OLEDs

[0234] The organic light emitting diode according to the present invention comprises at least two light emitting layers, namely the first light emitting layer and the second light emitting layer. The organic light emitting diode may further comprise other light emitting layers (third light emitting layer, fourth light emitting layer, etc.). In the case where the organic light emitting diode comprises more than two light emitting layers, only one electron transport layer stack may be arranged between two of the light emitting layers. Alternatively, there may be more than one electron transport layer stack. For example, in the case where the organic light emitting diode comprises a first light emitting layer, a second light emitting layer and a third light emitting layer, the first electron transport layer stack may be arranged between the first light emitting layer and the second light emitting layer, and the second electron transport layer stack may be arranged between the second light emitting layer and the third light emitting layer.

[0235] In the case where the organic light emitting diode comprises more than two light emitting layers, more than one charge generation layer may be present. For example, in the case where the organic light emitting diode comprises a first light emitting layer, a second light emitting layer and a third light emitting layer, the first charge generation layer may be arranged between the first light emitting layer and the second light emitting layer, and the second charge generation layer may be arranged between the second light emitting layer and the third light emitting layer.

[0236] In the case where the organic light emitting diode comprises more than two light emitting layers, more than one charge generation layer may be present. For example, in the case where the organic light emitting diode comprises a first light emitting layer, a second light emitting layer and a third light emitting layer, the first charge generation layer may be arranged between the first light emitting layer and the second light emitting layer, and the second charge generation layer may be arranged between the second light emitting layer and the third light emitting layer.

[0237] For the purposes of the present disclosure, a stack of layers is an arrangement of two or more different layers. The layers of the stack of layers may differ from each other according to the chemical nature of the materials contained in the respective layers, i.e. may be made of different compounds. The electron transport layer stack according to the present disclosure comprises at least two different layers, each made of an electron transport material.

[0238] The compound of formula (I) and / or the compound of formula (II) and / or the compound (III) may be different from each other. That is, the compound of formula (I) and / or the compound of formula (II) and / or the compound (III) may be different from each other in at least one structural aspect, in particular may be different from each other in at least one atom and / or group.

[0239] The first electron transport layer and the second electron transport layer do not contain an electrical dopant. In this regard, "do not contain" means that the corresponding compound (electrical dopant) is only contained in the corresponding layer, and it cannot be avoided by standard purification methods and ordinary technical means during the preparation of the corresponding layer. In this regard, the electrical dopant is particularly but not limited to an n-type electrical dopant. The n-type electrical dopant may be selected from a metal or an alkali metal, a metal salt or an alkaline earth metal salt and / or a rare earth metal salt, or an organic alkali metal complex or an alkali metal complex, or LiF, LiCl, LiBr, LiI, LiQ, a metal borate or a mixture thereof. In particular, the first electron transport layer and the second electron transport layer may not contain an n-type electrical dopant. The n-type electrical dopant may be a metal salt comprising at least one metal cation and at least one anion. The metal cation of the metal salt may be selected from alkali metals, alkaline earth metals and rare earth metals, or selected from Li, Na, K, Rb, Cs, Mg, Ca, Sr and Ba; or selected from Li, Mg, Ca and Sr. The anion of the metal salt may be selected from quinoline, phosphine oxide phenolate and borate.

[0240] In this regard, the n-type electrical dopant is, in particular but not limited to, a single metal, or an electropositive metal selected from alkali metals, alkaline earth metals, rare earth metals and transition metals, a transition metal; a metal salt, or an alkali metal salt, an alkaline earth metal salt and / or a rare earth metal salt, or a metal complex, or an alkali metal complex, an alkaline earth metal complex, a transition metal complex and / or a rare earth metal complex. Examples of n-type doping metal salts may be LiF, LiCl, LiBr, LiI, metal borates, metal quinolinates or mixtures thereof. Other examples of n-type electrical dopants are strong chemical reducing agents. Such "redox" n-type dopants may be generally characterized in that their highest occupied molecular orbital (HOMO) energy level is comparable to the lowest unoccupied molecular orbital energy level of the corresponding electron transport matrix, which is about -3.0 eV or lower in common OLED transport materials. It should be understood that the term "about -3.0 eV or less" refers to values ​​less negative than -3.0 eV, such as -2.8 eV, -2.5 eV, -2.3 eV, -2.1 eV, or values ​​less negative than -2.0 eV.

[0241] The n-type electrical dopant may be an organic compound disclosed in EP1837926A1, WO07107306A1 or WO07107356A1.

[0242] The proviso is that the electrical dopant does not emit substantially light.

[0243] The first electron transport layer stack may be disposed between the first light emitting layer and the first charge generating layer.

[0244] The first electron transport layer and the second electron transport layer may be in direct contact with each other.

[0245] The electron transport layer stack may consist of the first electron transport layer and the second electron transport layer.

[0246] The second electron transport layer may be in direct contact with the electron injection layer.

[0247] The electron injection layer may be composed of a plurality of separate electron injection sub-layers.

[0248] The electron injection layer may contain a metal or an alkali metal, a metal salt or an alkaline earth metal salt and / or a rare earth metal salt, or an organic alkali metal complex or an alkali metal complex, or LiF, LiCl, LiBr, LiI, LiQ, a metal borate or a mixture thereof.

[0249] The electron injection layer may be composed of a metal or an alkali metal, a metal salt or an alkaline earth metal salt and / or a rare earth metal salt, or an organic alkali metal complex or an alkali metal complex, or LiF, LiCl, LiBr, LiI, LiQ, a metal borate or a mixture thereof.

[0250] It may be provided that the compound of formula (II) is not contained in the electron injection layer. It may be provided that the compound of formula (I) is not contained in the electron injection layer. It may be provided that the compound (III) is not contained in the electron injection layer.

[0251] The compound of formula (I), the compound of formula (II) and the compound (III) may be different from each other and / or may not be contained in the electron injection layer, respectively.

[0252] The first electron transport layer stack may be disposed between the first light emitting layer and the first charge generating layer. The second electron transport layer of the first electron transport layer stack may be in direct contact with the first charge generating layer.

[0253] The first electron transport layer and the second electron transport layer may be in direct contact with each other.

[0254] The electron transport layer stack may consist of the first electron transport layer and the second electron transport layer.

[0255] The organic light emitting diode may further comprise an electron injection layer and a second electron layer stack, and the second electron layer stack is in direct contact with the electron injection layer. The second electron transport layer stack may contain the same compounds as the first layer stack, i.e., compounds (I), (II) and (III) as defined in the present disclosure, wherein the corresponding compounds may be independently selected.

[0256] It may be provided that the compound of formula (II) is not contained in the first charge generation layer. It may be provided that the compound of formula (I) is not contained in the first charge generation layer. It may be provided that the compound (III) is not contained in the first charge generation layer.

[0257] The compound of formula (I), the compound of formula (II) and the compound (III) may be different from each other and / or may not be contained in the first charge generating layer, respectively.

[0258] In case the organic light emitting device comprises more than one electron transport layer stack (ie, other electron transport layer stacks in addition to the first electron transport layer stack), all features described above with respect to the first electron transport layer stack are independently applicable to each electron transport layer stack.

[0259] In case the organic light emitting device comprises more than one charge generation layer (ie, further charge generation layers in addition to the first charge generation layer), all features described above with respect to the first charge generation layer may apply independently to each charge generation layer.

[0260] The organic light emitting diode may further include a substrate, wherein the substrate may be transparent or opaque.

[0261] Exemplary Embodiments

[0262] According to one embodiment, an organic light emitting diode is provided, the organic light emitting diode comprising an anode, a cathode, a first light emitting layer, a second light emitting layer, a first charge generation layer and a first electron transport layer stack; wherein

[0263] - the first charge generation layer is arranged between the first light-emitting layer and the second light-emitting layer;

[0264] - the first electron transport layer stack is arranged between the first light-emitting layer and the second light-emitting layer;

[0265] - the first electron transport layer stack comprises a first electron transport layer and a second electron transport layer;

[0266] - The first electron transport layer comprises a compound of formula (I):

[0267] (Ar 1 -A c ) a -X b (I);

[0268] -a and b are independently 1 or 2;

[0269] -c is independently 0 or 1;

[0270] -Ar 1Independently selected from C 6 To C 30 Aryl or C 2 To C 24 Heteroaryl,

[0271] - Each of Ar 1 may be substituted with one or two substituents independently selected from C 6 To C 12 Aryl, C 3 To C 11 Heteroaryl and C 1 To C 6 Alkyl, D, C 1 To C 6 Alkoxy, C 3 To C 6 Branched alkyl, C 3 To C 6 Cyclic alkyl, C 3 To C 6 Branched alkoxy, C 3 To C 6 Cyclic alkoxy, partially fluorinated or perfluorinated C 1 To C 6 Alkyl, partially fluorinated or perfluorinated C 1 To C 6 Alkoxy, partially deuterated or fully deuterated C 1 To C 6 Alkyl, partially deuterated or fully deuterated C 1 To C 6 Alkoxy, halogen, CN or PY(R 10 ) 2 , wherein Y is selected from O, S or Se, preferably O, and R 10 Independently selected from C 6 To C 12 Aryl, C 3 To C 12 Heteroaryl, C 1 To C 6 Alkyl, C 1 To C 6 Alkoxy, partially fluorinated or perfluorinated C 1 To C 6 Alkyl, partially fluorinated or perfluorinated C 1 To C 6 Alkoxy, partially deuterated or fully deuterated C 1 To C 6 Alkyl, partially deuterated or fully deuterated C 1 To C 6 Alkoxy;

[0272] -Ar 1 Each C on6 To C 12 Aryl Substituents and Ar 1 Each C on 3 To C 11 The heteroaryl substituent may be C 1 To C 4 Alkyl or halogen substituted;

[0273] -A is independently selected from C 6 To C 18 Aryl,

[0274] - wherein each A may be substituted with one or two substituents independently selected from C 6 To C 12 Aryl and C 1 To C 6 Alkyl, D, C 1 To C 6 Alkoxy, C 3 To C 6 Branched alkyl, C 3 To C 6 Cyclic alkyl, C 3 To C 6 Branched alkoxy, C 3 To C 6 Cyclic alkoxy, partially fluorinated or perfluorinated C 1 To C 6 Alkyl, partially fluorinated or perfluorinated C 1 To C 6 Alkoxy, partially deuterated or fully deuterated C 1 To C 6 Alkyl, partially deuterated or fully deuterated C 1 To C 6 Alkoxy, halogen, CN or PY(R 10 ) 2 , wherein Y is selected from O, S or Se, preferably O, and R 10 Independently selected from C 6 To C 12 Aryl, C 3 To C 12 Heteroaryl, C 1 To C 6 Alkyl, C 1 To C 6 Alkoxy, partially fluorinated or perfluorinated C 1 To C 6 Alkyl, partially fluorinated or perfluorinated C 1 To C 6 Alkoxy, partially deuterated or fully deuterated C 1 To C 6 Alkyl, partially deuterated or fully deuterated C 1To C 6 Alkoxy;

[0275] - where each C on A 6 To C 12 The aryl substituent may be C 1 To C 4 Alkyl or halogen substituted;

[0276] -X is independently selected from C 3 To C 21 Heteroaryl and C 6 To C 24 Aryl,

[0277] - wherein each X may be substituted with one or two substituents independently selected from C 6 To C 12 Aryl, C 3 To C 11 Heteroaryl and C 1 To C 6 Alkyl, D, C 1 To C 6 Alkoxy, C 3 To C 6 Branched alkyl, C 3 To C 6 Cyclic alkyl, C 3 To C 6 Branched alkoxy, C 3 To C 6 Cyclic alkoxy, partially fluorinated or perfluorinated C 1 To C 6 Alkyl, partially fluorinated or perfluorinated C 1 To C 6 Alkoxy, partially deuterated or fully deuterated C 1 To C 6 Alkyl, partially deuterated or fully deuterated C 1 To C 6 Alkoxy, halogen, CN or PY(R 10 ) 2 , wherein Y is selected from O, S or Se, preferably O, and R 10 Independently selected from C 6 To C 12 Aryl, C 3 To C 12 Heteroaryl, C 1 To C 6 Alkyl, C 1 To C 6 Alkoxy, partially fluorinated or perfluorinated C 1 To C 6 Alkyl, partially fluorinated or perfluorinated C 1 To C 6Alkoxy, partially deuterated or fully deuterated C 1 To C 6 Alkyl, partially deuterated or fully deuterated C 1 To C 6 Alkoxy;

[0278] - where each C on X 6 To C 12 The aryl substituent and each C 3 To C 11 The heteroaryl substituent may be C 1 To C 4 Alkyl or halogen substituted;

[0279] - the molecular dipole moment of the compound of formula (I) is ≥0D and ≤3.5D;

[0280] - The second electron transport layer comprises a compound of formula (II):

[0281] (Ar 2 ) m -(Z k -G) n (II);

[0282] - m and n are independently 1 or 2;

[0283] - k is independently 0, 1 or 2;

[0284] -Ar 2 Independently selected from C 3 To C 30 Heteroaryl and C 6 To C 42 Aryl,

[0285] - Each of Ar 2 may be substituted with one or two substituents independently selected from C 6 To C 12 Aryl, C 3 To C 11 Heteroaryl and C 1 To C 6 Alkyl, D, C 1 To C 6 Alkoxy, C 3 To C 6 Branched alkyl, C 3 To C 6 Cyclic alkyl, C 3 To C 6 Branched alkoxy, C 3 To C 6 Cyclic alkoxy, partially fluorinated or perfluorinated C 1 To C 6Alkyl, partially fluorinated or perfluorinated C 1 To C 6 Alkoxy, partially deuterated or fully deuterated C 1 To C 6 Alkyl, partially deuterated or fully deuterated C 1 To C 6 Alkoxy, halogen, CN or PY(R 10 ) 2 , wherein Y is selected from O, S or Se, preferably O, and R 10 Independently selected from C 6 To C 12 Aryl, C 3 To C 12 Heteroaryl, C 1 To C 6 Alkyl, C 1 To C 6 Alkoxy, partially fluorinated or perfluorinated C 1 To C 6 Alkyl, partially fluorinated or perfluorinated C 1 To C 6 Alkoxy, partially deuterated or fully deuterated C 1 To C 6 Alkyl, partially deuterated or fully deuterated C 1 To C 6 Alkoxy;

[0286] -Ar 2 Each C on 6 To C 12 Aryl Substituents and Ar 2 Each C on 3 To C 11 The heteroaryl substituent may be C 1 To C 4 Alkyl or halogen substitution;

[0287] -Z is independently selected from C 6 To C 18 Aryl,

[0288] - wherein each Z may be substituted with one or two substituents independently selected from C 6 To C 12 Aryl and C 1 To C 6 Alkyl, D, C 1 To C 6 Alkoxy, C 3 To C 6 Branched alkyl, C 3 To C 6 Cyclic alkyl, C 3 To C 6 Branched alkoxy, C3 To C 6 Cyclic alkoxy, partially fluorinated or perfluorinated C 1 To C 6 Alkyl, partially fluorinated or perfluorinated C 1 To C 6 Alkoxy, partially deuterated or fully deuterated C 1 To C 6 Alkyl, partially deuterated or fully deuterated C 1 To C 6 Alkoxy, halogen, CN or PY(R 10 ) 2 , wherein Y is selected from O, S or Se, preferably O, and R 10 Independently selected from C 6 To C 12 Aryl, C 3 To C 12 Heteroaryl, C 1 To C 6 Alkyl, C 1 To C 6 Alkoxy, partially fluorinated or perfluorinated C 1 To C 6 Alkyl, partially fluorinated or perfluorinated C 1 To C 6 Alkoxy, partially deuterated or fully deuterated C 1 To C 6 Alkyl, partially deuterated or fully deuterated C 1 To C 6 Alkoxy;

[0289] - where each C on Z 6 To C 12 The aryl substituent may be C 1 To C 4 Alkyl or halogen substituted;

[0290] -G is selected so that the dipole moment of the G-phenyl group of the compound is ≥2D and ≤6D;

[0291] - the first electron transport layer and the second electron transport layer do not contain electrical dopants;

[0292] - the first charge generation layer comprises a compound of formula (II), wherein the compound of formula (II) in the first charge generation layer is the same as the compound of formula (II) in the second electron transport layer; and

[0293] -G does not contain a P=O moiety.

[0294] According to one embodiment, an organic light emitting diode is provided, the organic light emitting diode comprising an anode, a cathode, a first light emitting layer, a second light emitting layer, a first charge generation layer and a first electron transport layer stack; wherein

[0295] - the first charge generation layer is arranged between the first light-emitting layer and the second light-emitting layer;

[0296] - the first electron transport layer stack is arranged between the first light-emitting layer and the second light-emitting layer;

[0297] - the first electron transport layer stack comprises a first electron transport layer and a second electron transport layer;

[0298] - The first electron transport layer comprises a compound of formula (I):

[0299] (Ar 1 -A c ) a -X b (I);

[0300] -a and b are independently 1 or 2;

[0301] -c is independently 0 or 1;

[0302] -Ar 1 Independently selected from phenyl, naphthyl, anthracenyl, fluoranthenyl, xanthene, dibenzofuranyl, pyrimidinyl, pyrazinyl, spiroxanthenyl, fluorenyl, spirofluorenyl, triphenylsilyl, tetraphenylsilyl, or a group having formula (IIa) or (IIb):

[0303]

[0304] in

[0305] - the asterisk symbol "*" indicates the binding position of the group of formula (IIa) to A; and

[0306] -R 1 To R 9 Independently selected from H, C 6 To C 12 Aryl and C 4 To C 10 heteroaryl;

[0307] -A is independently selected from phenylene, naphthylene, biphenylene and terphenylene, each of which may be substituted or unsubstituted;

[0308] -X is independently selected from C 2 To C 39 Containing N heteroaryl and C 6 To C 54Aryl, optionally selected from C 2 To C 36 Containing N heteroaryl and C 6 To C 48 Aryl, optionally selected from C 3 To C 30 Containing N heteroaryl and C 6 To C 42 Aryl, optionally selected from C 3 To C 27 Containing N heteroaryl and C 6 To C 36 Aryl, optionally selected from C 3 To C 24 Containing N heteroaryl and C 6 To C 30 Aryl, optionally selected from C 3 To C 21 Containing N heteroaryl and C 6 To C 24 Aryl. In this context, it may be provided that the corresponding N-containing heteroaryl group contains one or more N atoms as the only heteroatoms;

[0309] - The second electron transport layer comprises a compound of formula (II):

[0310] (Ar 2 ) m -(Z k -G) n (II);

[0311] - m and n are independently 1 or 2;

[0312] - k is independently 0, 1 or 2;

[0313] -Ar 2 Independently selected from C 2 To C 39 Containing N heteroaryl and C 6 To C 54 Aryl, optionally selected from C 2 To C 36 Containing N heteroaryl and C 6 To C 48 Aryl, optionally selected from C 3 To C 30 Containing N heteroaryl and C 6 To C 42 Aryl, optionally selected from C 3 To C 27 Containing N heteroaryl and C 6 To C 36 Aryl, optionally selected from C 3 To C 24 Containing N heteroaryl and C 6 To C30 Aryl, optionally selected from C 3 To C 21 Containing N heteroaryl and C 6 To C 24 Aryl. In this context, it may be provided that the corresponding N-containing heteroaryl group contains one or more N atoms as the only heteroatoms;

[0314] -Z is independently selected from C 6 To C 30 Aryl, alternatively selected from C 6 To C 24 Aryl, alternatively selected from C 6 To C 18 Aryl, alternatively selected from C 6 To C 12 aryl groups, which may be substituted or unsubstituted;

[0315] -G is selected from the group consisting of nitrile, benzonitrile, nicotinonitrile, amide, carboxamide and C 2 To C 17 heteroaryl, wherein the corresponding G may include one or more substituents attached to the group, wherein the one or more substituents are selected from phenyl, methyl, ethyl and pyridyl;

[0316] - the first electron transport layer and the second electron transport layer do not contain electrical dopants;

[0317] - the first charge generation layer comprises a compound of formula (II), wherein the compound of formula (II) in the first charge generation layer is the same as the compound of formula (II) in the second electron transport layer; and

[0318] -G does not contain a P=O moiety.

[0319] According to one embodiment, an organic light emitting diode is provided, the organic light emitting diode comprising an anode, a cathode, a first light emitting layer, a second light emitting layer, a first charge generation layer and a first electron transport layer stack; wherein

[0320] - the first charge generation layer is arranged between the first light-emitting layer and the second light-emitting layer;

[0321] - the first electron transport layer stack is arranged between the first light-emitting layer and the second light-emitting layer;

[0322] - the first electron transport layer stack comprises a first electron transport layer and a second electron transport layer;

[0323] - The first electron transport layer comprises a compound of formula (I):

[0324] (Ar 1 -A c) a -X b (I);

[0325] -a and b are independently 1 or 2;

[0326] -c is independently 0 or 1;

[0327] -Ar 1 independently selected from fluoranthenyl, dibenzofuranyl, pyrimidinyl, pyrazinyl, 9,9-dimethylfluorenyl, a group having formula (IIa), a group having formula (IIb),

[0328]

[0329] in

[0330] - the asterisk symbol "*" indicates the binding position of the group of formula (IIa) to A; and

[0331] -R 1 is H, and R 2 To R 5 are independently phenyl; or

[0332] -R 1 and R 3 is phenyl, and R 2 , R 4 and R 5 is H; or

[0333] -R 6 To R 9 is phenyl;

[0334] -A is independently selected from phenylene, naphthylene, biphenylene and terphenylene, each of which may be substituted or unsubstituted;

[0335] -X is independently selected from triazinyl, 1,2-diazinyl, 1,3-diazinyl, 1,4-diazinyl, quinazolinyl, benzoquinazolinyl, benzimidazolyl, quinolinyl, benzoquinolinyl, benzoacridinyl, dibenzoacridinyl, fluoranthenyl, anthracenyl, naphthyl, terphenylidene, phenanthrolinyl and dinaphthofuranyl, each of which may be substituted or unsubstituted;

[0336] - The second electron transport layer comprises a compound of formula (II):

[0337] (Ar 2 ) m -(Z k -G) n (II);

[0338] -Ar 2independently selected from pyridyl, triazine, 1,2-diazine, 1,3-diazine, 1,4-diazine, quinazolinyl, benzoquinazolinyl, benzimidazolyl, quinolinyl, benzoquinolinyl, benzoacridinyl, dibenzoacridinyl, fluoranthenyl, anthracenyl, naphthyl, terphenylidene, phenanthrolinyl and dinaphthofuranyl, each of which may be substituted or unsubstituted;

[0339] -Z is selected from phenylene, phenylene-naphthylene and biphenylene, each of which may be substituted or unsubstituted;

[0340] -G is selected from 2,2'-bipyridyl, 9-phenyl-1,10-phenanthrolinyl, 1,10-phenanthrolinyl and (pyridin-2-yl)imidazo[1,5-a]pyridinyl;

[0341] - the first electron transport layer and the second electron transport layer do not contain electrical dopants;

[0342] - the first charge generation layer comprises a compound of formula (II), wherein the compound of formula (II) in the first charge generation layer is the same as the compound of formula (II) in the second electron transport layer; and

[0343] -G does not contain a P=O moiety.

[0344] According to one embodiment, an organic light emitting diode is provided, the organic light emitting diode comprising an anode, a cathode, a first light emitting layer, a second light emitting layer, a first charge generation layer and a first electron transport layer stack; wherein

[0345] - the first charge generation layer is arranged between the first light-emitting layer and the second light-emitting layer;

[0346] - the first electron transport layer stack is arranged between the first light-emitting layer and the second light-emitting layer;

[0347] - the first electron transport layer stack comprises a first electron transport layer and a second electron transport layer;

[0348] - the first electron transport layer comprises a compound selected from compounds A-1 to A-41;

[0349] - the second electron transport layer comprises a compound selected from compounds B-1 to B-27;

[0350] - the first electron transport layer and the second electron transport layer do not contain electrical dopants;

[0351] - the first charge generation layer comprises a compound of formula (II), wherein the compound of formula (II) in the first charge generation layer is the same as the compound of formula (II) in the second electron transport layer; and

[0352] -G does not contain a P=O moiety.

[0353] Other layers

[0354] According to the present invention, in addition to the layers already mentioned above, the organic electronic device may further comprise other layers. Exemplary embodiments of the respective layers are described below:

[0355] Base

[0356] The substrate can be any substrate commonly used in the manufacture of electronic devices such as organic light emitting diodes. 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 can be a transparent as well as an opaque material, such as a glass substrate, a plastic substrate, a metal substrate or a silicon substrate.

[0357] Anode electrode

[0358] The first electrode or the second electrode included in the organic electronic device of the present invention may be an anode electrode. The anode electrode may be formed by depositing or sputtering a material for forming the anode electrode. The material for forming the anode electrode may be a high work function material to facilitate hole injection. The anode material may also be selected from a low work function material (i.e., aluminum). The anode electrode may be a transparent or reflective electrode. Transparent conductive oxides such as indium tin oxide (ITO), indium zinc oxide (IZO), tin dioxide (SnO 2 ), aluminum zinc oxide (AlZO) and zinc oxide (ZnO) to form the anode electrode. The anode electrode can also be formed using a metal, which is typically silver (Ag), gold (Au) or a metal alloy. The transparent or translucent anode can promote light emission through the anode.

[0359] Hole injection layer

[0360] The hole injection layer (HIL) can be formed on the anode electrode by vacuum deposition, spin coating, printing, casting, slot die coating, Langmuir-Broghe (LB) deposition, etc. When the HIL is formed using vacuum deposition, the deposition conditions may vary according to 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 ... -8 Support up to 10 -3 Torr pressure (1 Torr equals 133.322 Pa) and a deposition rate of 0.1 to 10 nm / s.

[0361] When the HIL is formed using spin coating or printing, 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, 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.

[0362] 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).

[0363] The HIL may include or consist of a p-type dopant, which may be selected from tetrafluoro-tetracyanoquinodimethane (F4TCNQ), 2,2'-(perfluoronaphthalene-2,6-diylidene)dimalononitrile, 4,4',4"-((1E,1'E,1"E)-cyclopropane-1,2,3-triylidenetris(cyanomethylidene))tris(2,3,5,6-tetrafluorobenzonitrile), or 2,2',2"-(cyclopropane-1,2,3-triylidene)tris(2-(p-cyanotetrafluorophenyl)acetonitrile), but is not limited thereto. The HIL may be selected from known hole transport host compounds doped with a p-type dopant. Typical examples are: copper phthalocyanine (CuPc), whose HOMO level is about -5.2 eV, doped with tetrafluorotetracyanoquinodimethane (F4TCNQ), whose LUMO level is about -5.2 eV; zinc phthalocyanine (ZnPc) (HOMO = -5.2 eV), which is doped with F4TCNQ; α-NPD (N,N'-bis(naphthalene-1-yl)-N,N'-bis(phenyl)-benzidine), which is doped with F4TCNQ. α-NPD is doped with 2,2'-(perfluoronaphthalene-2,6-diylidene) dimalononitrile. The p-type dopant concentration can be selected from 1 wt% to 20 wt%, more preferably 3 wt% to 10 wt%.

[0364] The thickness of the HIL may be within a range of about 1 nm to about 100 nm, and 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 substantially deteriorating driving voltage.

[0365] Hole transport layer

[0366] The hole transport layer (HTL) can be formed on the HIL by vacuum deposition, spin coating, slot die coating, printing, casting, Langmuir-Broghe (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.

[0367] The HTL can be formed of any compound commonly used to form an HTL. For example, Yasuhiko Shirota and Hiroshi Kageyama, Chem. Rev. 2007, 107, 953-1010 disclose compounds that may be suitable for use and are incorporated by reference. Examples of compounds that can 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 can transport holes and inhibit the diffusion of excitons into the EML.

[0368] 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 thickness of the HTL may be 170 nm to 200 nm.

[0369] When the thickness of the HTL is within this range, the HTL may have excellent hole transport characteristics without substantially deteriorating driving voltage.

[0370] Electron blocking layer

[0371] 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 LUMO energy level of the triarylamine compound may be closer to the vacuum energy level than the LUMO energy level of the hole transport layer. The HOMO energy level of the electron blocking layer may be further away from the vacuum energy level than the HOMO energy level of the hole transport layer. The thickness of the electron blocking layer may be selected between 2nm and 20nm.

[0372] If the electron blocking layer has a high triplet energy level it can also be described as a triplet controlling layer.

[0373] If a phosphorescent green or blue emitting layer is used, the function of the triplet control layer is to reduce triplet quenching. Thus, a higher luminous efficiency of the phosphorescent emitting 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 emitter in the adjacent emitting layer. EP 2 722 908 A1 describes compounds suitable for triplet control layers, in particular triarylamine compounds.

[0374] Emission layer (EML)

[0375] The EML can be formed on the HTL by vacuum deposition, spin coating, slot die coating, printing, casting, LB deposition, etc. When the EML is formed using 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.

[0376] It may be provided that the light-emitting layer contains no compound of the formula (I), no compound of the formula (II) and / or no compound (III).

[0377] The 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-vinylcarbazole) (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), distyrylarylene (DSA), and bis(2-(2-hydroxyphenyl)benzothiazole)zinc (Zn(BTZ)). 2 ).

[0378] 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.

[0379] Examples of red emitter dopants are PtOEP, Ir(piq) 3 and Btp 2 Ir(acac), but not limited thereto. These compounds are phosphorescent emitters, however, fluorescent red emitter dopants may also be used.

[0380] An example of a phosphorescent green emitter dopant is Ir(ppy) 3 (ppy = phenylpyridine), Ir(ppy)2 (acac), Ir(mpyp) 3 .

[0381] An example of a phosphorescent blue emitter dopant is F 2 Irpic, (F 2 ppy) 2 Ir(tmd) and Ir(dfppz) 3 Examples of fluorescent blue emitter dopants are 4,4'-bis(4-diphenylaminophenylvinyl)biphenyl (DPAVBi), 2,5,8,11-tetra-tert-butylperylene (TBPe).

[0382] 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 causing substantial damage to the driving voltage.

[0383] Hole Blocking Layer (HBL)

[0384] 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.

[0385] When the HBL is formed using 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 forming the HBL include Oxadiazole derivatives, triazole derivatives and phenanthroline derivatives.

[0386] The thickness of the HBL may be in the range of about 5 nm to about 100 nm, for example, in the range of 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 substantially deteriorating driving voltage.

[0387] Electron Transport Layer (ETL)

[0388] The OLED according to the present invention comprises at least two electron transport layers (ETL). At least two of the electron transport layers are a first electron transport layer and a second electron transport layer as defined herein. In addition, the OLED may comprise other ETLs which may or may not be as defined above. If the other ETL is not as defined above, its characteristics may be as follows.

[0389] According to various embodiments, the OLED may include an electron transport layer stack including at least one first electron transport layer (ETL-1) including a compound of formula (I) and at least one second electron transport layer (ETL-2) including a compound of formula (II).

[0390] By properly adjusting the energy level of a specific layer of the ETL, the injection and transport of electrons can be controlled, and holes can be effectively blocked. Therefore, the OLED can have a long lifespan, improved performance, and stability.

[0391] Electron injection layer (EIL)

[0392] The EIL that can facilitate the injection of electrons from the cathode into the second electron transport layer stack can be formed on the second electron transport layer stack, preferably directly formed on the second electron transport layer stack, preferably directly formed on the second electron transport layer of the second electron transport layer stack, and preferably directly in contact with the second electron transport layer of the second electron transport layer stack. Examples of materials for forming the EIL or included in the EIL include 8-hydroxyquinoline lithium (LiQ), LiF, NaCl, CsF, Li 2 O, BaO, Ca, Ba, Yb, Mg. 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. The EIL may include an organic matrix material doped with an n-type dopant. The matrix material may be selected from materials conventionally used as a matrix material for an electron transport layer.

[0393] The EIL may be composed of a plurality of separate EIL sub-layers. In the case where the EIL is composed of a plurality of separate EIL sub-layers, the number of sub-layers is preferably 2. The separate EIL sub-layers may include different materials for forming the EIL.

[0394] 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 characteristics without substantial impairment in driving voltage.

[0395] The electron transport stack of the present invention is not part of the electron injection layer.

[0396] Cathode electrode

[0397] The cathode electrode is formed on the existing EIL, preferably directly formed on the EIL, preferably in direct contact with the EIL. In the sense of the present invention, the cathode and the EIL can be regarded as a functional component capable of injecting electrons into the electron transport layer stack. The cathode electrode can be formed of a metal, an alloy, a conductive compound or a mixture thereof. The cathode electrode can have a low work function. For example, the cathode electrode can 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 can be formed of a transparent conductive oxide such as ITO or IZO.

[0398] 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. A transparent or translucent cathode may promote light emission through the cathode.

[0399] It is to be understood that the cathode electrode and the electron injection layer are not part of the second electron transport layer or any other part of the electron transport layer stack.

[0400] Charge generation layer

[0401] The charge generation layer (CGL) included in the OLED of the present invention, ie, the first CGL and any other CGLs, may include a p-type CGL and an n-type CGL. An intermediate layer may be disposed between the p-type layer and the n-type layer.

[0402] Typically, the charge generation layer GCL is a pn junction connecting an n-type charge generation layer (electron generation layer, n-type CGL) and an a-type charge generation layer (hole generation layer, p-type CGL). The n-side of the pn junction generates electrons and injects them into the layer adjacent to the anode in the direction. Similarly, the p-side of the pn junction generates holes and injects them into the layer adjacent to the cathode in the direction.

[0403] The charge generation layer is used in a tandem OLED (such as the one disclosed herein), which includes two or more light-emitting layers between a cathode and an anode. In a tandem OLED including two light-emitting layers, an n-type charge generation layer provides electrons to a first light-emitting layer arranged near the anode, and a hole generation layer provides holes to a second light-emitting layer arranged between the first light-emitting layer and the cathode.

[0404] The matrix material suitable for the hole generating layer can be a material conventionally used as a hole injection and / or hole transport matrix material. The p-type dopant used in the hole generating layer can also be a conventional material. For example, the p-type dopant can be selected from tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ), tetracyanoquinodimethane derivatives, radialene derivatives, iodine, FeCl 3 , FeF 3 and SbCl 5 The host may also be selected from N,N'-di(naphthalene-1-yl)-N,N-diphenylbenzidine (NPB), N,N'-diphenyl-N,N'-bis(3-methylphenyl)-1,1-biphenyl-4,4'-diamine (TPD) and N,N',N'-tetranaphthyl-benzidine (TNB). The p-type charge generation layer may be composed of CNHAT.

[0405] The n-type charge generation layer can be a pure n-type dopant layer, such as a positive metal layer, or can be composed of an organic matrix material doped with an n-type dopant. In one embodiment, the n-type dopant can be an alkali metal, an alkali metal compound, an alkaline earth metal, an alkaline earth metal compound, a transition metal, a transition metal compound or a rare earth metal. In another embodiment, the metal can be 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 can be selected from Cs, K, Rb, Mg, Na, Ca, Sr, Eu and Yb. The matrix material suitable for the n-type charge generation layer can be a material conventionally used as a matrix material for electron injection or electron transport layer. The matrix material can be selected from, for example, N-containing heterocyclic compounds such as triazine compounds or phenanthroline compounds such as compound E or bipyridine or terpyridine compounds, hydroxyquinoline derivatives such as tris (8-hydroxyquinoline) aluminum, benzoxazole derivatives and silylene derivatives.

[0406] The compound of formula (II) in the first charge generation layer is the same as the compound of formula (II) in the second electron transport layer.

[0407] The hole generation layer may be disposed in direct contact with the n-type charge generation layer.

[0408] The electron transport stack of the present invention is not part of the charge generation layer.

[0409] Organic Light Emitting Diode (OLED)

[0410] According to various embodiments of the present invention, an OLED layer may be provided that is arranged between the above-mentioned layers, on the substrate or on the top electrode.

[0411] According to one aspect of the present invention, an organic light-emitting diode is provided, comprising: a substrate, an anode, a first hole injection layer, a first hole transport layer, a first electron blocking layer, a first light-emitting layer, a first optional hole blocking layer, a first electron transport layer stack, a first charge generating layer, a hole generating layer, a second hole transport layer, a second electron blocking layer, a second light-emitting layer, a second optional hole blocking layer, a second electron transport layer stack, a second electron injection layer and a cathode.

[0412] According to one aspect of the present invention, an organic light-emitting diode is provided, which includes: a substrate, an anode, a hole injection layer, a first hole transport layer, a first electron blocking layer, a first light-emitting layer, a first electron transport layer stack including a first electron transport layer and a second electron transport layer, a first charge generating layer, a second hole transport layer, a second electron blocking layer, a second light-emitting layer, a second electron transport layer stack including a third electron transport layer (= the first electron transport layer of the second stack) and a fourth electron transport layer (= the second electron transport layer of the second stack), a second charge generating layer, a third hole transport layer, a third electron blocking layer, a third light-emitting layer, a third electron transport layer stack including a fifth electron transport layer (= the first electron transport layer of the third stack) and a sixth electron transport layer (= the second electron transport layer of the third stack), an electron injection layer and a cathode.

[0413] According to one aspect, the OLED may include the following layer structure: a substrate is arranged adjacent to an anode electrode, the anode electrode is arranged adjacent to a first hole injection layer, the first hole injection layer is arranged adjacent to a first hole transport layer, the first hole transport layer is arranged adjacent to a first electron blocking layer, the first electron blocking layer is arranged adjacent to a first light-emitting layer, the first light-emitting layer is arranged adjacent to a first charge generation layer, the first charge generation layer is arranged adjacent to a first electron transport layer stack comprising a first electron transport layer and a second electron transport layer, the first electron transport layer stack is arranged adjacent to an electron injection layer, and the electron injection layer is arranged adjacent to a cathode electrode.

[0414] For example, according to Figure 1 The OLED can be formed by the following method, wherein on the substrate 110, an anode 120, a first hole injection layer 130, a first hole transport layer 140, a first electron blocking layer 145, a first light-emitting layer 150, a first electron transport layer stack 160, a first charge generation layer including an n-type charge generation layer 185 and a hole generation layer 135, a second hole transport layer 141, a second electron blocking layer 146, a second light-emitting layer 151, a second electron transport layer stack 165, a second electron injection layer 181 and a cathode 190 are sequentially formed.

[0415] For example, according to Figure 2The OLED can be formed by the following method, wherein a hole injection layer 130, a first hole transport layer 140, a first electron blocking layer 145, a first light emitting layer 150, a first electron transport layer stack 160 including a first electron transport layer 161 and a second electron transport layer 162, a first charge generation layer 184 including an n-type CGL sublayer 184a and a p-type CGL sublayer 184b, a second hole transport layer 141, a second electron blocking layer 146, a second light emitting layer 151, a first electron transport layer stack 160 including a third electron transport layer (= a first electron transport layer of the second stack) are sequentially formed on the anode 120. a second electron transport layer stack 165 including a fifth electron transport layer (= the first electron transport layer of the third stack) 163 and a sixth electron transport layer (= the second electron transport layer of the third stack) 164, an electron injection layer 181 and a cathode 190.

[0416] According to another aspect of the present invention, there is provided a method for manufacturing an organic electronic device, the method using:

[0417] - at least one deposition source, preferably two deposition sources, more preferably at least three deposition sources.

[0418] Suitable deposition methods may include:

[0419] -Deposition by vacuum thermal evaporation;

[0420] - deposition by solution processing, preferably selected from spin coating, printing, casting; and / or

[0421] -Slot die coating.

[0422] In case the second electron transport layer(s) comprise compound (III) and a compound of formula (II), the two compounds may be deposited by co-deposition from two separate deposition sources or as a premix from a single source.

[0423] According to various embodiments of the present invention, the method may further include forming a light emitting layer on the anode electrode, and forming at least one layer selected from a hole injection layer, a hole transport layer or an electron hole blocking layer between the anode electrode and the first electron transport layer.

[0424] According to various embodiments of the present invention, the method may further include the step of forming an organic light emitting diode (OLED), wherein

[0425] - forming a first anode electrode on the substrate,

[0426] - forming a light emitting layer on the first anode electrode,

[0427] - forming an electron transport layer stack on the light emitting layer, and forming a first charge generating layer on the electron transport layer stack,

[0428] -Finally, the cathode electrode is formed,

[0429] - forming an optional hole injection layer and a hole transport layer in sequence between the first anode electrode and the light-emitting layer,

[0430] - forming a charge generation layer between the electron transport layer stack and the cathode electrode.

[0431] According to various embodiments, the OLED may have the following layer structure, wherein the layers have the following order:

[0432] an anode, a hole injection layer, a hole transport layer, an electron blocking layer, an emissive layer, an optional hole blocking layer, an electron transport layer stack, an n-type CGL, a p-type CGL, a hole transport layer, an electron blocking layer, an emissive layer, an optional hole blocking layer, an electron transport layer stack, a first charge generation layer comprising an n-type CGL and a p-type CGL, a hole transport layer, an electron blocking layer, an emissive layer, an optional hole blocking layer, an electron transport layer stack, an electron injection layer, and a cathode.

[0433] According to another aspect of the present invention, an electronic device is provided, the electronic device comprising at least one organic light-emitting device according to any embodiment described in the entire application, preferably, the electronic device comprises an organic light-emitting diode in one of the embodiments described in the entire application. More preferably, the electronic device is a display device or a lighting device.

[0434] In one embodiment, the organic electronic device according to the present invention may further include a layer containing a radialene compound and / or a quinodimethane compound.

[0435] In one embodiment, the radialene compound and / or the quinodimethane compound may be substituted with one or more halogen atoms and / or one or more electron withdrawing groups. The electron withdrawing group may be selected from a nitrile group, a halogenated alkyl group, or a fully halogenated alkyl group, or a fully fluorinated alkyl group. Other examples of electron withdrawing groups may be acyl, sulfonyl or phosphoryl groups.

[0436] Alternatively, the acyl group, sulfonyl group and / or phosphoryl group may contain halogenated and / or perhalogenated hydrocarbon groups. In one embodiment, the perhalogenated hydrocarbon group may be a perfluorinated hydrocarbon group. Examples of perfluorinated hydrocarbon groups may be perfluoromethyl, perfluoroethyl, perfluoropropyl, perfluoroisopropyl, perfluorobutyl, perfluorophenyl, perfluorotolyl; Examples of sulfonyl groups containing halogenated hydrocarbon groups may be trifluoromethylsulfonyl, pentafluoroethylsulfonyl, pentafluorophenylsulfonyl, heptafluoropropylsulfonyl, nonafluorobutylsulfonyl, etc.

[0437] In one embodiment, the radialene compound and / or the quinodimethane compound may be included in a hole injection layer, a hole transport layer, and / or a hole generation layer.

[0438] In one embodiment, the radialene compound may have formula (XX) and / or the quinodimethane compound may have formula (XXIa) or (XXIb):

[0439]

[0440] Where R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 11 , R 12 , R 15 , R 16 , R 20 , R 21 are independently selected from the above electron withdrawing groups, and R 9 , R 10 , R 13 , R 14 , R 17 , R 18 , R 19 , R 22 , R 23 and R 24 Independently selected from H, halogen and the above-mentioned electron withdrawing groups.

[0441] The embodiments are described in more detail below with reference to examples. However, the present disclosure is not limited to the following examples. Reference will now be made in detail to the exemplary aspects.

[0442] General Definition

[0443] In this specification, when no definition is otherwise provided, an "alkyl group" may refer to an aliphatic hydrocarbon group. The alkyl group may refer to a "saturated alkyl group" without any double or triple bonds. As used herein, the term "alkyl" will encompass straight chain as well as branched and cyclic alkyl groups. For example, C 3 The alkyl group may be selected from n-propyl and isopropyl. 4 Alkyl encompasses n-butyl, sec-butyl and tert-butyl. 6 The alkyl group encompasses n-hexyl and cyclohexyl.

[0444] As used herein, if not explicitly mentioned, an asterisk symbol "*" indicates a binding position where a correspondingly labeled moiety is bonded to another moiety.

[0445] C n The subscript number n in relates to the total number of carbon atoms in the corresponding alkyl, arylene, heteroarylene or aryl group.

[0446] As used herein, the term "aryl" or "arylene" shall encompass phenyl (C 6 The term "aryl" or "heteroaryl" refers to a group connected to two other parts. In this specification, the term "aryl group" or "arylene group" may refer to a group comprising at least one hydrocarbon aromatic part, and all elements of the hydrocarbon aromatic part may have a conjugated p orbital, such as a phenyl group, a naphthyl group, an anthracene group, a phenanthrene group, a pyridyl group, a fluorenyl group, etc. Spirocyclic compounds are also covered, wherein two aromatic parts are connected to each other by a spiral atom, such as 9,9'-spirodi[9H-fluorene] base. The aryl or arylene group may include a monocyclic or fused ring polycyclic (i.e., connecting a shared adjacent carbon atom pair) functional group.

[0447] As used herein, the term "heteroaryl" refers to an aryl group in which at least one carbon atom is replaced by a heteroatom. The term "heteroaryl" may refer to an aromatic heterocycle having at least one heteroatom, and all elements of the hydrocarbon heteroaromatic portion may have a p orbital forming a conjugation. The heteroatom may be selected from N, O, S, B, Si, P, Se, preferably selected from N, O and S. The sub-heteroaryl ring may contain at least 1 to 3 heteroatoms. Preferably, the sub-heteroaryl ring may contain at least 1 to 3 heteroatoms selected from N, S and / or O, respectively. As in the case of "aryl" / "arylene", the term "heteroaryl" includes, for example, spiro compounds in which two aromatic moieties are connected to each other, such as spiro[fluorene-9,9'-xanthene]. Other exemplary heteroaryl groups are diazines, triazines, dibenzofurans, dibenzothiofurans, acridines, benzoacridines, dibenzoacridines, etc.

[0448] As used herein, the term "alkenyl" refers to a group containing a carbon-carbon double bond -CR 1 =CR 2 R 3 .

[0449] As used herein, the term "perhalogenated" refers to a hydrocarbyl group in which all of the hydrogen atoms of the hydrocarbyl group are replaced by halogen (F, Cl, Br, I) atoms.

[0450] As used herein, the term "alkoxy" refers to a structural fragment of the formula -OR, wherein R is a hydrocarbon group, preferably an alkyl group or a cycloalkyl group.

[0451] As used herein, the term "thioalkyl" refers to a structural fragment of the formula -SR, wherein R is a hydrocarbon group, preferably an alkyl group or a cycloalkyl group.

[0452] C n -heteroaryl refers only to the number of carbon atoms, not the number of heteroatoms. 3 Heteroarylene groups are aromatic compounds containing three carbon atoms, such as pyrazole, imidazole, Azoles, thiazoles, etc.

[0453] As used herein, the term "heteroaryl" shall encompass pyridine, quinoline, benzoquinoline, quinazoline, benzoquinazoline, pyrimidine, pyrazine, triazine, benzimidazole, benzothiazole, benzo[4,5]thieno[3,2-d]pyrimidine, carbazole, xanthene, phenanthroline, Azine, benzoacridine, dibenzoacridine, etc.

[0454] In this specification, the term single bond means a direct bond.

[0455] As used herein, the term "fluorinated" refers to a hydrocarbon group in which at least one of the hydrogen atoms contained in the hydrocarbon group is replaced by a fluorine atom. A fluorinated group in which all hydrogen atoms are replaced by fluorine atoms is called a perfluorinated group, specifically referred to by the term "fluorinated".

[0456] For the purposes of the present invention, a group is "substituted" with another group if one of the hydrogen atoms contained in the group is replaced with another group, wherein the other group is a substituent.

[0457] 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 those two layers. A layer deposited on top of another layer is considered to be in direct contact with this layer.

[0458] The term "sandwiched in contact" refers to a three-layer arrangement in which the layer in the middle is in direct contact with the two adjacent layers.

[0459] With regard to the electron transport layer stack of the invention, the compounds mentioned in the experimental part are most preferred.

[0460] A lighting device can be any device used for illumination, irradiation, signaling or projection. They are classified accordingly as lighting devices, irradiation devices, signaling devices and projection devices. A lighting device usually consists of the following components: a source of optical radiation, a device that transmits the radiation flux into space in a desired direction, and a housing that connects these components into a single device and protects the radiation source and the optical transmission system from damage and influences of the surrounding environment.

[0461] According to another aspect, the organic electroluminescent device according to the invention comprises two or three or more light-emitting layers. OLEDs comprising more than one light-emitting layer are also described as tandem OLEDs or stacked OLEDs.

[0462] Organic electroluminescent devices (OLEDs) can be bottom or top emitting devices. Organic electroluminescent devices (OLEDs) can emit light through a transparent anode or through a transparent cathode.

[0463] Another aspect relates to a device comprising at least one organic electroluminescent device (OLED).

[0464] Devices comprising organic light emitting diodes are, for example, displays or lighting panels.

[0465] In the present invention, the following defined terms shall apply unless a different definition is given in the claims or elsewhere in this specification.

[0466] In the context of this specification, the term "different" or "different" in relation to a host material means that the host materials differ in structural formula.

[0467] 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 organic light emitting diodes as well as organic light emitting transistors (OLETs).

[0468] As used herein, "weight percent," "wt %," "percent by weight," "weight %" and variations thereof refer to a composition, component, substance or agent as the weight of that component, substance or agent of a corresponding electron transport layer divided by the total weight of its corresponding electron transport layer and multiplied by 100. It is 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 that it does not exceed 100 weight percent.

[0469] As used herein, "volume percent," "vol %," "percent by volume," "vol %" and variations thereof refer to a composition, component, substance or agent as the volume of that component, substance or agent of a corresponding electron transport layer divided by the total volume of its corresponding electron transport layer and multiplied by 100. It is understood that the total volume percent amount of all components, substances and agents of the cathode layer is selected so that it does not exceed 100 volume %.

[0470] Whether or not explicitly stated, it is assumed herein that all numerical values ​​are modified by the term "about". As used herein, the term "about" refers to the possible quantitative variation that may occur. Whether or not modified by the term "about", the claims include equivalents of the stated quantities.

[0471] It must be noted that, as used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the content clearly dictates otherwise.

[0472] The terms "does not contain", "does not contain", and "does not include" do not exclude impurities. Impurities have no technical impact on the objectives to be achieved by the present invention.

[0473] 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 emission spectrum of a device is less than 10%, preferably less than 5%, relative to the visible emission spectrum. The visible emission spectrum is the emission spectrum with a wavelength of about ≥380 nm to about ≤780 nm.

[0474] Preferably, the organic semiconductor layer comprising the compound of formula (I) is substantially non-luminescent or non-luminescent.

[0475] The working voltage is also called U, which is 10 mA / cm2. 2 ) is measured in volts (V).

[0476] Candela / ampere efficiency is also called cd / A efficiency, which is expressed in terms of 10 mA / cm2. 2 ) candela / ampere measurement under .

[0477] External quantum efficiency is also called EQE and is measured in percentage (%).

[0478] The color space is described by the coordinates CIE-x and CIE-y (International Commission on Illumination, 1931). CIE-y is particularly important for blue light. The smaller the CIE-y, the darker the blue color. Compare the efficiency values ​​at the same CIE-y.

[0479] The highest occupied molecular orbital (also known as HOMO) and the lowest unoccupied molecular orbital (also known as LUMO) are measured in electron volts (eV).

[0480] The terms "OLED", "organic light emitting diode", "organic light emitting device", "organic optoelectronic device" and "organic light emitting diode" are used concurrently and have the same meaning.

[0481] The terms "life span" and "lifetime" are used concurrently and have the same meaning.

[0482] The anode and cathode may be described as anode electrode / cathode electrode or anode electrode / cathode electrode or anode electrode layer / cathode electrode layer.

[0483] Room temperature, also known as ambient temperature, is 23°C. BRIEF DESCRIPTION OF THE DRAWINGS

[0484] These and / or other aspects and advantages of the present invention will become apparent and more readily understood from the following description of exemplary embodiments in conjunction with the accompanying drawings, in which:

[0485] Figure 1 is a schematic cross-sectional view of a multi-light-emitting layer organic light-emitting diode (OLED) according to an exemplary embodiment of the present invention;

[0486] Figure 2 is a schematic cross-sectional view of a multi-light-emitting layer OLED according to an exemplary embodiment of the present invention. DETAILED DESCRIPTION

[0487] 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. Exemplary embodiments are described below with reference to the drawings to explain aspects of the present invention.

[0488] In this document, when a first element is referred to as being formed or disposed "on" or formed or disposed "on" a second element, the first element may be directly disposed on the second element, or one or more other elements may be disposed between them. When a first element is referred to as being "directly formed or disposed on" or "directly formed or disposed on" a second element, no other elements are disposed between them.

[0489] Figure 11 is a schematic cross-sectional view of an organic light emitting diode (OLED) 200 according to an exemplary embodiment of the present invention. The OLED 200 includes a substrate 110, an anode 120, a first hole injection layer (HIL-1) 130, a first hole transport layer (HTL-1) 140, a first electron blocking layer (EBL-1) 145, a first light emitting layer (EML-1) 150, a first electron transport layer (ETL-1) stack 160 including a first electron transport layer 161 of a first stack and a second electron transport layer 162 of a first stack, an n-type charge generation layer (n-type CGL) 185 and a hole generation layer (p-type Charge generation layer; a first charge generation layer of a p-type GCL) 135, a second hole transport layer (HTL-2) 141, a second electron blocking layer (EBL-2) 146, a second light-emitting layer (EML-2) 151, a second electron transport layer (ETL-2) stack 165 including a third electron transport layer (= first electron transport layer of the second stack) 166 and a fourth electron transport layer (= second electron transport layer of the second stack) 167, an electron injection layer (EIL) 181 and a cathode 190.

[0490] refer to Figure 2 OLED 200 includes an anode 120, a hole injection layer (HIL) 130, a first hole transport layer (HTL-1) 140, a first electron blocking layer (EBL-1) 145, a first light emitting layer (EML-1) 150, a first electron transport layer (ETL-1) stack 160 including a first electron transport layer 161 and a second electron transport layer 162, a first charge generation layer (CGL-1) 184, a second hole transport layer (HTL-2) 141, a second electron blocking layer (EBL-2) 146, a second light emitting layer (EML-2) 151, a first electron transport layer (ETL-1) stack 160 including a first electron transport layer 161 and a second electron transport layer 162, )166 and a fourth electron transport layer (= the second electron transport layer of the second stack) 167, a second charge generation layer (CGL-2) 186, a third hole transport layer (HTL-3) 142, a third electron blocking layer (EBL-3) 147, a third light-emitting layer (EML-3) 152, a third electron transport layer (ETL-3) stack 168 including a fifth electron transport layer (= the first electron transport layer of the third stack) 163 and a sixth electron transport layer (= the second electron transport layer of the third stack) 164, an electron injection layer (EIL) 181 and a cathode 190. Figure 2 The OLED shown has a first light emitting portion A, a second light emitting portion B and a third light emitting portion C.

[0491] although Figure 1 and Figure 2Although not shown in the figure, a sealing layer may be further formed on the cathode electrode 190 to seal the OLED 200. In addition, various other modifications may be made thereto.

[0492] 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 one or more exemplary embodiments of the present invention.

[0493] Detailed Description

[0494] Melting point

[0495] The melting point (mp) was determined as the peak temperature of the DSC curve of the above TGA-DSC measurement or a separate DSC measurement (Mettler Toledo DSC822e, the sample was heated from room temperature to complete melting at a heating rate of 10 K / min under a pure nitrogen flow. A sample amount of 4 mg to 6 mg was placed in a 40 μL Mettler-Toledo aluminum pan with a lid and a hole of <1 mm was punched in the lid).

[0496] Glass transition temperature

[0497] The glass transition temperature (Tg) was measured as described in DIN EN ISO 11357, published March 2010, in a Mettler Toledo DSC 822e differential scanning calorimeter under nitrogen and using a heating rate of 10 K / min.

[0498] Rate start temperature

[0499] The rate onset temperature (TRO) was determined by loading 100 mg of the compound into a VTE source. As VTE source, point sources for organic materials provided by Kurt J. Lesker (www.lesker.com) or CreaPhys Ltd. (http: / / www.creaphys.com) can be used. -5 The VTE source is heated at a constant rate of 15K / min at a pressure of mbar and the temperature inside the VTE source is measured with a thermocouple. The evaporation of the compound is detected with a QCM detector, which detects the deposition of the compound on the quartz crystal of the detector. The deposition rate on the quartz crystal is measured in angstroms / second. To determine the rate onset temperature, the deposition rate is plotted against the VTE source temperature. The rate onset temperature is the temperature at which a significant deposition appears on the QCM detector. To obtain accurate results, the VTE source is heated and cooled three times and only the results of the second and third runs are used to determine the rate onset temperature.

[0500] In order to achieve good control of the evaporation rate of the organic compound, the rate start temperature may be in the range of 200°C to 255°C. If the rate start temperature is below 200°C, the evaporation may be too fast and thus difficult to control. If the rate start temperature is above 255°C, the evaporation rate may be too low, which may result in a short production cycle time, and the organic compounds in the VTE source may decompose due to long-term exposure to high temperatures.

[0501] The rate onset temperature is an indirect measure of the volatility of a compound. The higher the rate onset temperature, the lower the volatility of the compound.

[0502] Reduction potential

[0503] Reduction potential is measured at room temperature by cyclic voltammetry with constant potential device Metrohm PGSTAT30 and software MetrohmAutolab GPES. The redox potential given under a specific compound is in an argon-degassed 0.1M anhydrous THF solution of the measured object, under an argon atmosphere, using 0.1M tetrabutylammonium hexafluorophosphate supporting electrolyte, between platinum working electrodes and with an Ag / AgCl pseudo-standard electrode (Metrohm silver rod electrode) consisting of silver wires covered with silver chloride and directly immersed in the measured solution, measured at a scan rate of 100mV / s. The first run is carried out in the widest potential range set on the working electrode, and then the range is appropriately adjusted in subsequent runs. The last three runs are carried out when ferrocene (with 0.1M concentration) is added as a standard. The potential average corresponding to the cathode and anode peaks of the studied compound is deducted for standard Fc + The values ​​reported above were obtained by averaging the cathodic and anodic potentials observed for the α / Fc redox couple. All studied compounds as well as the reported comparative compounds showed clear reversible electrochemical properties.

[0504] Dipole moment

[0505] Dipole moment of molecules containing N atoms Given by:

[0506]

[0507] where q i and is the partial charge and position of atom i in the molecule.

[0508] The dipole moments were determined by the semiempirical molecular orbital method.

[0509] The geometry of the molecular structure was optimized in the gas phase using the hybrid functional B3LYP with the 6-31G* basis set as implemented in the program package TURBOMOLE V6.5 (TURBOMOLE GmbH, Litzenhardtstrasse 19, 76135 Karlsruhe, Germany). If more than one conformation was feasible, the conformation with the lowest total energy was selected to determine the bond lengths of the molecule.

[0510] Calculate HOMO and LUMO

[0511] HOMO and LUMO were calculated using the program package TURBOMOLE V6.5 (TURBOMOLE GmbH, Litzenhardtstrasse 19, 76135 Karlsruhe, Germany). The optimized geometry of the molecular structure and the HOMO and LUMO energy levels were determined by applying the hybrid functional B3LYP with the 6-31G* basis set in the gas phase. If more than one conformation is feasible, the conformation with the lowest total energy is selected.

[0512] Synthesis Procedure

[0513] The synthesis of compound B-1 is described in WO 2021 / 105518 A1. The synthesis of compound B-2 is described in WO2021 / 058761A1. The synthesis of compound B-3 is described in WO2021 / 116225A1. The synthesis of compound B-4 is described in WO 2021 / 058761 A1. The synthesis of compound B-5 is described in JP 2008-189660 A. The synthesis of compound G (=(2-([1,1'-biphenyl]-3-yl)-4-phenyl-6-(3-(10-phenylanthracene-9-yl)phenyl)-1,3,5-triazine)) is described in WO2020 / 120794A1.

[0514] General procedure for manufacturing OLED

[0515] Manufacturing of Comparative Example (CompEx)

[0516] For the top-emitting OLED device, a substrate with a size of 150 mm × 150 mm × 0.7 mm was ultrasonically cleaned with a 2% aqueous solution of Deconex FPD211 for 7 minutes, then ultrasonically cleaned with pure water for 5 minutes, and dried in a spin rinse dryer for 15 minutes. -5 Up to 10 -7 Ag was deposited at a pressure of 100 mbar as the anode.

[0517] Then, HT-1 and D-1 were vacuum co-deposited on the anode to form a HIL. Then, HT-1 was vacuum deposited on the HIL to form a HTL. Then, HT-2 was vacuum deposited on the HTL to form an electron blocking layer (EBL).

[0518] Then, a first light emitting layer was formed on the EBL by co-depositing host-1 and emitter-1.

[0519] Then, the compound of formula (I) is vacuum deposited onto the light-emitting layer to form a first electron transport layer.

[0520] Then, a second electron transport layer is formed on the first electron transport layer by depositing a premix of compound F and compound (III).

[0521] Then, an n-type CGL is formed on the second electron transport layer by co-depositing compound F and lithium.

[0522] Then, HT-1 and D-1 were vacuum co-deposited on the n-type CGL to form a p-type CGL.

[0523] Then, HT-1 was vacuum deposited on the p-type CGL to form a HTL. Then, HT-2 was vacuum deposited on the HTL to form an EBL.

[0524] Then, a second light emitting layer was formed on the EBL by co-depositing host-1 and emitter-1.

[0525] Then, the compound of formula (I) is vacuum deposited onto the light emitting layer to form a first electron transport layer. Then, a second electron transport layer is formed on the first electron transport layer by depositing a premix of compound F and compound (III).

[0526] Then, n-CGL is formed on the second electron transport layer by co-depositing compound F and lithium.

[0527] Then, HT-1 and D-1 were vacuum co-deposited on the n-type CGL to form a p-type CGL.

[0528] Then, HT-1 was vacuum deposited on the HIL to form a HTL. Then, HT-2 was vacuum deposited on the HTL to form an electron blocking layer (EBL).

[0529] Then, a third light emitting layer was formed on the EBL by co-depositing host-1 and emitter-1.

[0530] Then, the compound of formula (I) is vacuum deposited onto the light-emitting layer to form a first electron transport layer. Then, a second electron transport layer is formed on the first electron transport layer by depositing compound E and compound (III). Then, a double-layer electron injection layer is formed on the electron transport layer by first depositing LiQ and then Yb.

[0531] Then at 10 -7 0.01 to mbar Ag:Mg is evaporated at a rate of to form a cathode.

[0532] A HT-3 capping layer was formed on the cathode.

[0533] Production of Inventive Examples (OLED-1 to OLED-5)

[0534] For OLED Examples 1 to 5, compound F was replaced by compounds of formula (II), ie compounds B-1 to B-5, respectively.

[0535] In all examples, compound (III) is compound G.

[0536] Details of the layer stack for the top-emitting OLED device are as follows. Slashes " / " separate the individual layers. The layer thicknesses are given in square brackets […] and the mixing ratios in wt % are given in round brackets (…):

[0537] Details of the layer stack used in the OLED device containing compound (III):

[0538] Ag[100nm] / HT-1:D-1(volume%92:8)[10nm] / HT-1[24nm] / HT-2[5nm] / H09:BD200(wt%97:3)[20nm] / Compound of formula (I)[5nm] / {Compound of formula (II) or F}:Compound of formula (III)(wt%30:70)[25nm] / {Compound of formula (II) or F}:Li(wt%99:1)[15nm] / HT-1:D-1(volume%90:10)[10nm] / HT-1[36nm] / HT-2[5nm] / H09:BD200(wt%97:3)[20nm] / Compound of formula (I)[5nm ] / {compound of formula (II) or F}):compound of formula (III) (wt% 30:70)[25nm] / {compound of formula (II) or F}:Li(wt%99:1)[15nm] / HT-1:D-1(volume%90:10)[10nm] / HT-1[57nm] / HT-2[5nm] / H09:BD200(wt%97:3)[20nm] / compound of formula (I)[5nm] / {compound of formula (II) or F}:compound of formula (III) (wt%30:70)[30nm] / LiQ[1nm] / Yb[2nm] / Ag:Mg(wt%90:10)[13nm] / HT-3[65nm]

[0539] Table 5: List of compounds used

[0540]

[0541]

[0542] Technical Effects of the Invention

[0543] OLED devices according to the present invention show improved driving voltage and improved CEff in devices comprising an electron transport layer stack according to the present invention.

[0544] Table 5:

[0545] Performance of an organic electroluminescent tandem device comprising the compound of formula (I) in the first electron transport layer and the compound of formula (II) or comparative compound F in the second electron transport layer and the first charge generation layer.

[0546] Table 6:

[0547] Example Formula (II) Compound (III) nC CIE-y Relative V Relative CEff CompEx F G(70％) BPhen_Li (1%) 0.134 100 100 OLED-1 B-3 G(70％) B-3: Li (1%) 0,136 76 139 OLED-2 B-2 G(70％) B-2: Li (1%) 0,139 74 142 OLED-3 B-4 G(70％) B-4: Li (1%) 0,126 79 138 OLED-4 B-1 G(70％) B-1: Li (1%) 0,13 74 138 OLED-5 B-5 G(70％) B-5: Li (1%) 0,14 76 138

[0548] The features disclosed in the above description and in the dependent claims may, both alone and in any combination thereof, serve as material for implementing aspects of the disclosure in different forms as set out in the independent claims.

Claims

1. An organic light emitting diode, comprising an anode, a cathode, a first light emitting layer, a second light emitting layer, a first charge generating layer and a first electron transport layer stack; in - the first charge generation layer is arranged between the first light-emitting layer and the second light-emitting layer; - the first electron transport layer stack is arranged between the first light-emitting layer and the second light-emitting layer; - the first electron transport layer stack comprises a first electron transport layer and a second electron transport layer; - The first electron transport layer comprises a compound of formula (I): (Ar 1 -A c ) a -X b (I); -a and b are independently 1 or 2; -c is independently 0 or 1; -Ar 1 Independently selected from C6 to C 60 Aryl or C2 to C 42 Heteroaryl, - Each of Ar 1 It may be substituted with one or two substituents independently selected from C6 to C 12 Aryl, C3 to C 11 heteroaryl and C1 to C6 alkyl, D, C1 to C6 alkoxy, C3 to C6 branched alkyl, C3 to C6 cyclic alkyl, C3 to C6 branched alkoxy, C3 to C6 cyclic alkoxy, partially fluorinated or perfluorinated C1 to C6 alkyl, partially fluorinated or perfluorinated C1 to C6 alkoxy, partially deuterated or perdeuterated C1 to C6 alkyl, partially deuterated or perdeuterated C1 to C6 alkoxy, halogen, CN or PY (R 10 )2, wherein Y is selected from O, S or Se, preferably O, and R 10 Independently selected from C6 to C 12 Aryl, C3 to C 12 Heteroaryl, C1 to C6 alkyl, C1 to C6 alkoxy, partially fluorinated or perfluorinated C1 to C6 alkyl, partially fluorinated or perfluorinated C1 to C6 alkoxy, partially deuterated or perdeuterated C1 to C6 alkyl, partially deuterated or perdeuterated C1 to C6 alkoxy; -Ar 1 Each C6 to C 12 Aryl substituents and Ar 1 Each C3 to C 11 The heteroaryl substituent may be substituted with C1 to C4 alkyl or halogen; -A is independently selected from C6 to C 30 Aryl, - wherein each A may be substituted with one or two substituents independently selected from C6 to C 12 Aryl and C1 to C6 alkyl, D, C1 to C6 alkoxy, C3 to C6 branched alkyl, C3 to C6 cyclic alkyl, C3 to C6 branched alkoxy, C3 to C6 cyclic alkoxy, partially fluorinated or perfluorinated C1 to C6 alkyl, partially fluorinated or perfluorinated C1 to C6 alkoxy, partially deuterated or perdeuterated C1 to C6 alkyl, partially deuterated or perdeuterated C1 to C6 alkoxy, halogen, CN or PY (R 10 )2, wherein Y is selected from O, S or Se, preferably O, and R 10 Independently selected from C6 to C 12 Aryl, C3 to C 12 Heteroaryl, C1 to C6 alkyl, C1 to C6 alkoxy, partially fluorinated or perfluorinated C1 to C6 alkyl, partially fluorinated or perfluorinated C1 to C6 alkoxy, partially deuterated or perdeuterated C1 to C6 alkyl, partially deuterated or perdeuterated C1 to C6 alkoxy; - Each C6 to C on A 12 The aryl substituents may be substituted with C1 to C4 alkyl or halogen; -X is independently selected from C2 to C 42 Heteroaryl and C6 to C 60 Aryl, - wherein each X may be substituted with one or two substituents independently selected from C6 to C 12 Aryl, C3 to C 11 heteroaryl and C1 to C6 alkyl, D, C1 to C6 alkoxy, C3 to C6 branched alkyl, C3 to C6 cyclic alkyl, C3 to C6 branched alkoxy, C3 to C6 cyclic alkoxy, partially fluorinated or perfluorinated C1 to C6 alkyl, partially fluorinated or perfluorinated C1 to C6 alkoxy, partially deuterated or perdeuterated C1 to C6 alkyl, partially deuterated or perdeuterated C1 to C6 alkoxy, halogen, CN or PY (R 10 )2, wherein Y is selected from O, S or Se, preferably O, and R 10 Independently selected from C6 to C 12 Aryl, C3 to C 12 Heteroaryl, C1 to C6 alkyl, C1 to C6 alkoxy, partially fluorinated or perfluorinated C1 to C6 alkyl, partially fluorinated or perfluorinated C1 to C6 alkoxy, partially deuterated or perdeuterated C1 to C6 alkyl, partially deuterated or perdeuterated C1 to C6 alkoxy; - where each C6 to C on X 12 The aryl substituent and each C3 to C 11 The heteroaryl substituent may be substituted with C1 to C4 alkyl or halogen; - the molecular dipole moment of the compound of formula (I) is ≥0D and ≤4D; - The second electron transport layer comprises a compound of formula (II): (The 2 ) m -(Z k -G) n (II); - m and n are independently 1 or 2; - k is independently 0, 1 or 2; -Ar 2 Independently selected from C2 to C 42 Heteroaryl and C6 to C 60 Aryl, - Each of Ar 2 It may be substituted with one or two substituents independently selected from C6 to C 12 Aryl, C3 to C 11 heteroaryl and C1 to C6 alkyl, D, C1 to C6 alkoxy, C3 to C6 branched alkyl, C3 to C6 cyclic alkyl, C3 to C6 branched alkoxy, C3 to C6 cyclic alkoxy, partially fluorinated or perfluorinated C1 to C6 alkyl, partially fluorinated or perfluorinated C1 to C6 alkoxy, partially deuterated or perdeuterated C1 to C6 alkyl, partially deuterated or perdeuterated C1 to C6 alkoxy, halogen, CN or PY (R 10 )2, wherein Y is selected from O, S or Se, preferably O, and R 10 Independently selected from C6 to C 12 Aryl, C3 to C 12 Heteroaryl, C1 to C6 alkyl, C1 to C6 alkoxy, partially fluorinated or perfluorinated C1 to C6 alkyl, partially fluorinated or perfluorinated C1 to C6 alkoxy, partially deuterated or perdeuterated C1 to C6 alkyl, partially deuterated or perdeuterated C1 to C6 alkoxy; -Ar 2 Each C6 to C 12 Aryl substituents and Ar 2 Each C3 to C 11 The heteroaryl substituent may be substituted with C1 to C4 alkyl or halogen; -Z is independently selected from C6 to C 30 Aryl, - wherein each Z may be substituted with one or two substituents independently selected from C6 to C 12 Aryl and C1 to C6 alkyl, D, C1 to C6 alkoxy, C3 to C6 branched alkyl, C3 to C6 cyclic alkyl, C3 to C6 branched alkoxy, C3 to C6 cyclic alkoxy, partially fluorinated or perfluorinated C1 to C6 alkyl, partially fluorinated or perfluorinated C1 to C6 alkoxy, partially deuterated or perdeuterated C1 to C6 alkyl, partially deuterated or perdeuterated C1 to C6 alkoxy, halogen, CN or PY (R 10 )2, wherein Y is selected from O, S or Se, preferably O, and R 10 Independently selected from C6 to C 12 Aryl, C3 to C 12 Heteroaryl, C1 to C6 alkyl, C1 to C6 alkoxy, partially fluorinated or perfluorinated C1 to C6 alkyl, partially fluorinated or perfluorinated C1 to C6 alkoxy, partially deuterated or perdeuterated C1 to C6 alkyl, partially deuterated or perdeuterated C1 to C6 alkoxy; - where each C6 to C on Z 12 The aryl substituents may be substituted with C1 to C4 alkyl or halogen; -G is selected so that the dipole moment of the G-phenyl group of the compound is ≥1D and ≤7D; - the first electron transport layer and the second electron transport layer do not contain electrical dopants; - the first charge generation layer comprises a compound of formula (II), wherein the compound of formula (II) in the first charge generation layer is the same as the compound of formula (II) in the second electron transport layer; and -G does not contain a P=O moiety.

2. The organic light emitting diode according to claim 1, wherein Ar 1 Independently selected from phenyl, naphthyl, anthracenyl, fluoranthenyl, xanthene, dibenzofuranyl, pyrimidinyl, pyrazinyl, spiroxanthenyl, fluorenyl, spirofluorenyl, triphenylsilyl, tetraphenylsilyl, or a group having formula (IIa) or (IIb): in - the asterisk symbol "*" indicates the binding position of the group of formula (IIa) to A; and -R 1 To R 9 Independently selected from H, C6 to C 12 Aryl and C4 to C 10 Heteroaryl.

3. The organic light emitting diode according to claim 1, wherein Ar 1 independently selected from fluoranthenyl, dibenzofuranyl, pyrimidinyl, pyrazinyl, 9,9-dimethylfluorenyl, a group having formula (IIa), a group having formula (IIb), in - the asterisk symbol "*" indicates the binding position of the group of formula (IIa) to A; and -R 1 is H, and R 2 To R 5 are independently phenyl; or -R 1 and R 3 is phenyl, and R 2 , R 4 and R 5 is H; or -R 6 To R 9 It is phenyl.

4. An organic light emitting diode according to any one of the preceding claims, wherein A is selected from phenylene, naphthylene, biphenylene and terphenylene, each of which may be substituted or unsubstituted.

5. An organic light emitting diode according to any one of the preceding claims, wherein X is independently selected from triazine, 1,2-diazine, 1,3-diazine, 1,4-diazine, quinazolinyl, benzoquinazolinyl, benzimidazolyl, quinolinyl, benzoquinolinyl, benzoacridinyl, dibenzoacridinyl, fluoranthenyl, anthracenyl, naphthyl, terphenylidene, phenanthrolinyl and dinaphthofuranyl, each of which may be substituted or unsubstituted.

6. An organic light emitting diode according to any one of the preceding claims, wherein Ar 2 Independently selected from pyridyl, triazine, 1,2-diazine, 1,3-diazine, 1,4-diazine, quinazolinyl, benzoquinazolinyl, benzimidazolyl, quinolinyl, benzoquinolinyl, benzoacridinyl, dibenzoacridinyl, fluoranthenyl, anthracenyl, naphthyl, terphenylidene, phenanthrolinyl and dinaphthofuranyl, each of which may be substituted or unsubstituted.

7. An organic light emitting diode according to any one of the preceding claims, wherein -G is selected from the group consisting of nitrile, benzonitrile, nicotinonitrile, amide, carboxamide and C2 to C 17 heteroaryl; - The corresponding G may include one or more substituents attached to the group, wherein the one or more substituents are selected from phenyl, methyl, ethyl and pyridyl.

8. An organic light-emitting diode according to any one of the preceding claims, wherein G is selected from 2,2'-bipyridyl, 9-phenyl-1,10-phenanthrolinyl, 1,10-phenanthrolinyl, (pyridin-2-yl)imidazo[1,5-a]pyridinyl, 2-pyridin-2-yl-quinolyl and terpyridyl.

9. An organic light emitting diode according to any one of the preceding claims, wherein G is selected such that the compound G-phenyl is represented by one of the following structures:

10. An organic light-emitting diode according to any one of the preceding claims, wherein the compound of formula (II) is selected from B-1 to B-27:

11. An organic light-emitting diode according to any one of the preceding claims, wherein the second electron transport layer further comprises compound (III), wherein the compound (III) comprises 8 to 13 aromatic or heteroaromatic rings, optionally 8 to 11 aromatic or heteroaromatic rings, optionally 9 or 10 aromatic or heteroaromatic rings. 12 . The organic light emitting diode according to claim 11 , wherein the compound (III) comprises 1 to 5 heteroaromatic rings. 13 . The organic light-emitting diode according to claim 11 , wherein if the compound (III) comprises two or more heteroaromatic rings, the heteroaromatic rings are separated from each other by at least one aromatic ring containing no heteroatoms.

14. An organic light emitting diode according to any one of the preceding claims, wherein the first electron transport layer stack is arranged between the first light emitting layer and the first charge generating layer. 15 . The organic light emitting diode according to claim 1 , wherein the first electron transport layer and the second electron transport layer are in direct contact with each other.

16. An organic light emitting diode according to any one of the preceding claims, wherein the second electron transport layer is in direct contact with the first charge generation layer.

17. An organic light emitting diode according to any one of the preceding claims, wherein the first charge generation layer comprises a metal, or an alkali metal, or a metal salt.

18. A device comprising an organic light emitting diode according to any one of the preceding claims, wherein the device is a display device or a lighting device and light is emitted through a transparent cathode.

19. A device comprising the organic light emitting diode according to claims 1 to 17, wherein the device is a display device or a lighting device, and light is emitted through the transparent anode.

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