Material composition for organic electroluminescent devices

Abstract

The present invention describes a composition comprising a hole-transporting host material, an electron-transporting host material, and a phosphorescent metal complex as well as devices comprising these compositions, especially OLEDs including an emission layer comprising these compositions.

Description

[0001] Material composition for organic electroluminescent devices

[0002] The present invention describes a composition comprising a hole-transporting host material and a material having TADF (thermally activated delayed fluorescence) properties, as well as devices comprising these compositions, especially OLEDs including an emission layer comprising these compositions.

[0003] The structure of organic electroluminescent devices, more particularly organic light emitting diodes (OLEDs), in which organic semiconductors are used as functional materials is described, for example, in US 4,539,507. In general, a distinction is made between fluorescent and phosphorescent OLEDs, where fluorescent OLEDs employ a fluorescent emitter as emitting compound and phosphorescent OLEDs employ a phosphorescent emitter as an emitting compound.

[0004] OLEDs having an emitting layer comprising a sensitizer in combination with a fluorescent emitter have been described in the prior art in the last decade. In these systems, the sensitizer transfers its energy to the fluorescent emitter in order to increase the efficiency of the fluorescent emission. The sensitizer can be a phosphorescent organometallic complex as described, for example, in US 2021 / 0104682. Such OLEDs are generally referred to as hyperphosphorescent OLED. The sensitizer can also be an organic material showing thermally activated delayed fluorescence (TADF) as described, for example, in WO 2015 / 022974. Such OLEDs are generally referred to as hyperfluorescent OLEDs.

[0005] Alternatively, OLEDs are developed in which an organic material having TADF properties is used as the emitter. Such OLEDs are referred to as TADF OLEDs in this application.

[0006] There is still a need for improvement of OLED performance, especially in terms of lifetime, efficiency and operating voltage of the OLEDs, as well as for the colour to be achieved.

[0007] An important starting point for achieving the said improvements is, depending on the emitting system, the choice of the host materials, sensitizers and emitters in the emitting layer. In particular, there is still a need for hole-transporting host materials having a high triplet energy for use in hyperfluorescent OLEDs or in TADF OLEDs.

[0008] An emitter is taken to mean a fluorescent compound which emits light during operation of the electronic device. A sensitizer is taken to mean a compound that transfers energy to the fluorescent emitter, to facilitate light emission. Typically, a sensitizer in hyperfluorescent devices is an organic compound having TADF properties.

[0009] A host is taken to mean a compound which is generally present in the mixture in a greater proportion than the emitter and / or the sensitizer compound. The terms matrix and host are used synonymously in accordance to the present invention. The host preferably does not emit light during operation of the electronic device.

[0010] Even if a plurality of different hosts are present in the mixture of the emitting layer, their individual proportions are typically greater than the proportion of the emitters.

[0011] If a mixture of a plurality of compounds is present in the emitting layer, the emitter is typically the component present in smaller amount, i.e. in a smaller proportion than the other compounds present in the mixture of the emitting layer. In this case, the emitter is also referred to as dopant.

[0012] Even if a plurality of different hosts are present in the mixture of the emitting layer, their individual proportions are typically greater than the proportion of the sensitizer compounds, or the proportions of the individual sensitizer compounds, if a plurality of sensitizer compounds are present in the mixture of the emitting layer.

[0013] Host materials, organic sensitizers (TADF compounds) and fluorescent emitters for use in organic electronic devices are well known to the person skilled in the art. However, there is still need for improvement in the case of use of a combination of host materials, organic sensitizers or TADF emitters and fluorescent emitters in the emitting layer, especially in relation to efficiency, operating voltage and / or lifetime of the organic electronic device.

[0014] The problem addressed by the present invention is that of providing compositions, which are especially suitable as compositions for emitting layers in hyperfluorescent OLEDs or TADF OLEDs.

[0015] Surprisingly, it has been found that compositions comprising the compounds described in more detail below solve this problem and are particularly suitable for use in hyperfluroescent OLEDs and TADF OLEDs. In particular, such OLEDs have a long lifetime, a high efficiency and a low operating voltage. These compositions as well as electronic devices, in particular organic electroluminescent devices, containing these compositions are therefore the object of the present invention. The invention therefore provides a composition comprising:

[0016] (1) a compound having a difference of the lowest excited singlet energy and the triplet energy of < 1.0 eV (TADF compound); and

[0017] (2) a compound of the following formula (1):

[0018] Formula (1) where the symbols and indices used are as follows:

[0019] M is Si or Ge, preferably Si;

[0020] X is on each occurrence, identically or differently, OR or N, with the proviso that not more than two X per cycle are N;

[0021] RM1, RM2are on each occurrence, identically or differently, a straight-chain alkyl group having 1 to 20 C atoms or branched or a cyclic alkyl group having 3 to 20 C atoms where one or more H atoms of the straight-chain, branched or cyclic alkyl group may be replaced by D or F, or an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, which may be substituted by one or more radicals R; the radicals RM1and RM2may be linked to one another and form a mono- or polycyclic aromatic or heteroaromatic ring system, which may be substituted by one or more radicals R;

[0022] RN1, RN2are on each occurence, identically or differently, an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, which may in each case be substituted by one or more radicals R; when n = m = 1 , the radicals RN1and RM1and / or RN2and RM2may be linked to one another and form a mono- or polycyclic aromatic or heteroaromatic ring system, which may be substituted by one or more radicals R; and when n = 2, two radicals RN1and / or two radicals RN2may be linked to one another and form a mono- or polycyclic aromatic or heteroaromatic ring system, which may be substituted by one or more radicals R;

[0023] R is on each occurrence, identically or differently, H, D, F, Cl, Br, I, OH, CHO, CN, C(=O)Ar, P(=O)(Ar)2, S(=O)Ar, S(=O)2Ar, N(R1)2, N(Ar)2, NO2, Si(R1)3, Ge(R1)3, B(OR1)2, OSO2R , a straight-chain alkyl, alkoxy or thioalkyl group having 1 to 40 C atoms or branched or a cyclic alkyl, alkoxy or thioalkyl group having 3 to 40 C atoms, each of which may be substituted by one or more radicals R1, where in each case one or more non-adjacent CH2groups may be replaced by R1C=CR1, C=C, Si(R1)2, Ge(R1)2, C=O, P(=O)(R1), SO, SO2, O, S or CONR1and where one or more H atoms may be replaced by D, F, Cl, Br, I, CN or NO2, an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, which may in each case be substituted by one or more radicals R1, or an aryloxy group having 5 to 60 aromatic ring atoms, which may be substituted by one or more radicals R1; where two radicals R may form a mono- or polycyclic, aliphatic ring system, aromatic or heteroaromatic ring system, which may be substituted by one or more radicals R1;

[0024] Ar is, on each occurrence, identically or differently, an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, which may in each case also be substituted by one or more radicals R1;

[0025] R1is on each occurrence, identically or differently, H, D, F, Cl, Br, I, CN, a straight-chain alkyl, alkoxy or thioalkyl group having 1 to 20 C atoms or branched or cyclic alkyl, alkoxy or thioalkyl group having 3 to 20 C atoms, where in each case one or more non-adjacent CH2groups may be replaced by SO, SO2, O, S and where one or more H atoms may be replaced by D, F, Cl, Br or I, or an aromatic or heteroaromatic ring system having 5 to 24 aromatic ring atoms; n is 1 or 2; m is (2-n); and the composition does not comprise a metal complex.

[0026] Furthermore, the following definitions of chemical groups apply for the purposes of the present application: An aryl group in the sense of this invention contains 6 to 60 aromatic ring atoms, preferably 6 to 40 aromatic ring atoms, more preferably 6 to 20 aromatic ring atoms; a heteroaryl group in the sense of this invention contains 5 to 60 aromatic ring atoms, preferably 5 to 40 aromatic ring atoms, more preferably 5 to 20 aromatic ring atoms, at least one of which is a heteroatom. The heteroatoms are preferably selected from N, O and S. This represents the basic definition. If other preferences are indicated in the description of the present invention, for example with respect to the number of aromatic ring atoms or the heteroatoms present, these apply.

[0027] An aryl group or heteroaryl group here is taken to mean either a simple aromatic ring, i.e. benzene, or a simple heteroaromatic ring, for example pyridine, pyrimidine or thiophene, or a condensed (annellated) aromatic or heteroaromatic polycycle, for example naphthalene, phenanthrene, quinoline or carbazole. A condensed (annellated) aromatic or heteroaromatic polycycle in the sense of the present application consists of two or more simple aromatic or heteroaromatic rings condensed with one another.

[0028] An aryl or heteroaryl group, which may in each case be substituted by the above-mentioned radicals and which may be linked to the aromatic or heteroaromatic ring system via any desired positions, is taken to mean, in particular, groups derived from benzene, naphthalene, anthracene, phenanthrene, pyrene, dihydropyrene, chrysene, perylene, fluoranthene, benzanthracene, benzophenanthrene, tetracene, pentacene, benzopyrene, furan, benzofuran, isobenzofuran, dibenzofuran, thiophene, benzothiophene, isobenzothiophene, dibenzothiophene, pyrrole, indole, isoindole, carbazole, pyridine, quinoline, isoquinoline, acridine, phenanthridine, benzo-5,6-quinoline, benzo-6,7-quinoline, benzo-7,8- quinoline, phenothiazine, phenoxazine, pyrazole, indazole, imidazole, benzimidazole, naphthimidazole, phenanthrimidazole, pyridimidazole, pyrazinimidazole, quinoxalinimi- dazole, oxazole, benzoxazole, naphthoxazole, anthroxazole, phenanthroxazole, isoxazole, 1 ,2-thiazole, 1,3-thiazole, benzothiazole, pyridazine, benzopyridazine, pyrimidine, benzopyrimidine, quinoxaline, pyrazine, phenazine, naphthyridine, azacarbazole, benzocarboline, phenanthroline, 1 ,2,3-triazole, 1 ,2,4-triazole, benzotriazole, 1,2,3-oxadiazole, 1,2,4-oxa- diazole, 1,2,5-oxadiazole, 1,3,4-oxadiazole, 1,2,3-thiadiazole, 1 ,2,4-thiadiazole, 1 ,2,5- thiadiazole, 1,3,4-thiadiazole, 1 ,3,5-triazine, 1 ,2,4-triazine, 1 ,2,3-triazine, tetrazole, 1 , 2,4,5- tetrazine, 1,2,3,4-tetrazine, 1,2,3,5-tetrazine, purine, pteridine, indolizine and benzothiadiazole.

[0029] An aryloxy group in accordance with the definition of the present invention is taken to mean an aryl group, as defined above, which is bonded via an oxygen atom. An analogous definition applies to heteroaryloxy groups. An aromatic ring system in the sense of this invention contains 6 to 60 C atoms in the ring system, preferably 6 to 40 C atoms, more preferably 6 to 20 C atoms. A heteroaromatic ring system in the sense of this invention contains 5 to 60 aromatic ring atoms, preferably 5 to 40 aromatic ring atoms, more preferably 5 to 20 aromatic ring atoms, at least one of which is a heteroatom. The heteroatoms are preferably selected from N, O and / or S. An aromatic or heteroaromatic ring system in the sense of this invention is intended to be taken to mean a system which does not necessarily contain only aryl or heteroaryl groups, but instead in which, in addition, a plurality of aryl or heteroaryl groups may be connected by a nonaromatic unit (preferably less than 10% of the atoms other than H), such as, for example, an sp3-hybridised C, Si, N or O atom, an sp2-hybridised C or N atom or an sp-hybridised C atom. Thus, for example, systems such as 9,9’-spirobifluorene, 9,9’-diarylfluorene, triarylamine, diaryl ether, stilbene, etc., are also intended to be taken to be aromatic ring systems in the sense of this invention, as are systems in which two or more aryl groups are connected, for example, by a linear or cyclic alkyl, alkenyl or alkynyl group or by a silyl group. Furthermore, systems in which two or more aryl or heteroaryl groups are linked to one another via single bonds are also taken to be aromatic or heteroaromatic ring systems in the sense of this invention, such as, for example, systems such as biphenyl, terphenyl or diphenyltriazine.

[0030] An aromatic or heteroaromatic ring system having 5 - 60 aromatic ring atoms, which may in each case also be substituted by radicals as defined above and which may be linked to the aromatic or heteroaromatic group via any desired positions, is taken to mean, in particular, groups derived from benzene, naphthalene, anthracene, benzanthracene, phenanthrene, benzophenanthrene, pyrene, chrysene, perylene, fluoranthene, naphthacene, pentacene, benzopyrene, biphenyl, biphenylene, terphenyl, terphenylene, quaterphenyl, fluorene, spirobifluorene, dihydrophenanthrene, dihydropyrene, tetrahydropyrene, cis- or trans- indenofluorene, truxene, isotruxene, spirotruxene, spiroisotruxene, furan, benzofuran, isobenzofuran, dibenzofuran, thiophene, benzothiophene, isobenzothiophene, dibenzothiophene, pyrrole, indole, isoindole, carbazole, indolocarbazole, indenocarbazole, pyridine, quinoline, isoquinoline, acridine, phenanthridine, benzo-5,6-quinoline, benzo-6,7-quinoline, benzo-7,8-quinoline, phenothiazine, phenoxazine, pyrazole, indazole, imidazole, benzimidazole, naphthimidazole, phenanthrimidazole, pyridimidazole, pyrazinimidazole, quinoxalin- imidazole, oxazole, benzoxazole, naphthoxazole, anthroxazole, phenanthroxazole, isoxa- zole, 1,2-thiazole, 1,3-thiazole, benzothiazole, pyridazine, benzopyridazine, pyrimidine, benzopyrimidine, quinoxaline, 1,5-diazaanthracene, 2,7-diazapyrene, 2,3-diazapyrene, 1,6-diazapyrene, 1 ,8-diazapyrene, 4,5-diazapyrene, 4,5,9, 10-tetraazaperylene, pyrazine, phenazine, phenoxazine, phenothiazine, fluorubin, naphthyridine, azacarbazole, benzo- carboline, phenanthroline, 1 ,2,3-triazole, 1 ,2,4-triazole, benzotriazole, 1 ,2,3-oxadiazole,

[0031] 1.2.4-oxadiazole, 1 ,2,5-oxadiazole, 1 ,3,4-oxadiazole, 1 ,2,3-thiadiazole, 1 ,2,4-thiadiazole,

[0032] 1.2.5-thiadiazole, 1 ,3,4-thiadiazole, 1 ,3,5-triazine, 1 ,2,4-triazine, 1 ,2,3-triazine, tetrazole,

[0033] 1.2.4.5-tetrazine, 1 ,2,3,4-tetrazine, 1 ,2,3,5-tetrazine, purine, pteridine, indolizine and benzothiadiazole, or combinations of these groups.

[0034] For the purposes of the present invention, a straight-chain alkyl group having 1 to 40 C atoms or a branched or cyclic alkyl group having 3 to 40 C atoms or an alkenyl or alkynyl group having 2 to 40 C atoms, in which, in addition, individual H atoms or CH2 groups may be substituted by the groups mentioned above under the definition of the radicals, is preferably taken to mean the radicals methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, s-butyl, t-butyl, 2-methylbutyl, n-pentyl, s-pentyl, cyclopentyl, neopentyl, n-hexyl, cyclohexyl, neohexyl, n-heptyl, cycloheptyl, n-octyl, cyclooctyl, 2-ethylhexyl, trifluoromethyl, pentafluoroethyl, 2,2,2-trifluoroethyl, ethenyl, propenyl, butenyl, pentenyl, cyclopentenyl, hexenyl, cyclohexenyl, heptenyl, cycloheptenyl, octenyl, cyclooctenyl, ethynyl, propynyl, butynyl, pentynyl, hexynyl or octynyl. An alkoxy or thioalkyl group having 1 to 40 C atoms is preferably taken to mean methoxy, trifluoromethoxy, ethoxy, n-propoxy, i-propoxy, n-butoxy, i-butoxy, s-butoxy, t-butoxy, n-pentoxy, s-pentoxy, 2-methylbutoxy, n-hexoxy, cyclohexyloxy, n-heptoxy, cycloheptyloxy, n-octyloxy, cyclooctyloxy, 2-ethylhexyloxy, pentafluoroethoxy, 2,2,2-trifluoroethoxy, methylthio, ethylthio, n-propylthio, i-propylthio, n- butylthio, i-butylthio, s-butylthio, t-butylthio, n-pentylthio, s-pentylthio, n-hexylthio, cyclohexylthio, n-heptylthio, cycloheptylthio, n-octylthio, cyclooctylthio, 2-ethylhexylthio, trifluoromethylthio, pentafluoroethylthio, 2,2,2-trifluoroethylthio, ethenylthio, propenylthio, butenylthio, pentenylthio, cyclopentenylthio, hexenylthio, cyclohexenylthio, heptenylthio, cycloheptenylthio, octenylthio, cyclooctenylthio, ethynylthio, propynylthio, butynylthio, pentynylthio, hexynylthio, heptynylthio or octynylthio.

[0035] The formulation that two radicals may form a ring with one another is, for the purposes of the present application, intended to be taken to mean, inter alia, that the two radicals are linked to one another by a chemical bond. This is illustrated by the following schemes:

[0036] Furthermore, the above-mentioned formulation is also intended to be taken to mean that, in the case where one of the two radicals represents hydrogen, the second radical is bonded at the position to which the hydrogen atom was bonded, with formation of a ring. This is illustrated by the following scheme:

[0037] Ri f i

[0038] When two radicals form a ring with one another, then it is preferred that the two radicals are adjacent radicals. Adjacent radicals in the sense of the present invention are radicals which are bonded to atoms which are linked directly to one another or which are bonded to the same atom.

[0039] When the index n = 2, then the index m = 0 and the formula (1) corresponds to formula (2), and when the index n = 1, then the index m = 1 and the formula (1) corresponds to formula (3):

[0040] Formula (2) Formula (3) where the symbols have the same meanings as above and M is preferably Si.

[0041] In a further preferred embodiment, X is on each occurrence, identically or differently, CR.

[0042] Preferred compounds of formula (1) are selected from the compounds of the formulae (2-1) and (3-1),

[0043] where the symbols have the same meaning as above.

[0044] In a further preferred embodiment, n = 2 and m = 0.

[0045] In accordance with a particularly preferred embodiment, the compound of formula (1) is selected from the compounds of formula (2-1a) and (3-1a):

[0046] Formula (2-1 a) Formula (3-1 a) where the symbols have the same meanings as above.

[0047] Preferably, the groups RN1, RN2are on each occurence, identically or differently, an aromatic or heteroaromatic ring system having 6 to 40, preferably 5 to 30, even more preferably 6 to 24, particularly preferably 6 to 18 aromatic ring atoms, which may in each case be substituted by one or more radicals R.

[0048] In a further preferred embodiment, the groups RM1and RM2are on each occurrence, identically or differently, an aromatic or heteroaromatic ring system having 6 to 40, more preferably 6 to 30, particularly preferably 6 to 18 aromatic ring atoms, which may in each case be substituted by one or more radicals R. Preferred embodiments of the groups RN1, RN2, RM1and / or RM2are on each occurrence, identically or differently, selected from phenyl, biphenyl, terphenyl, quaterphenyl, fluorene, spirobifluorene, naphthalene, indol, benzofuran, benzothiophene, dibenzofuran, carbazole, dibenzothiophene, indenocarbazole, indolocarbazole, pyridine, pyrimidine, pyrazine, pyridazine, triazine, quinoline, quinazoline, benzimidazole, benzimidazobenzimidazole, phenanthrene or triphenylene, each of which may be substituted by one or more substituents R, preferably non-aromatic substituents R.

[0049] Preferred groups RN1, RN2, RM1and / or RM2are at each occurrence, identically or differently, selected from the groups of the following formulae (Ar-1) to (Ar-133),

[0050]

[0051]

[0052] Ar-117

[0053] where R has the meanings as defined above, the dashed bond indicates for RN1and RN2the bond to the N atom and for RM1and RM2the bond to M in formula (1) and furthermore:

[0054] Ar* is on each occurrence, identically or differently, a bivalent aromatic or heteroaromatic ring system having 6 to 18 aromatic ring atoms which may be substituted by one or more substituents R; A1is on each occurrence, identically or differently, BR, C(R)2, C=O, NR, O or S; p is 0 or 1 where p = means that the group Ar* is not present and that the corresponding aromatic or heteroarmatic group is bound directly to the N atom for RN1and RN2and is bound directly to M for RM1and RM2; r is 0 or 1 where r = 0 means that no group A1is bound in this position and that substituents R are bound to the C atoms instead.

[0055] Preferably, R is on each occurrence, identically or differently, H, D, F, CN, Si(R1)a, a straight-chain alkyl or alkoxy group having 1 to 20, preferably 1 to 10, more preferably 1 to 5 C atoms or branched or a cyclic alkyl or alkoxy group having 3 to 20, preferably 3 to 10, more preferably 3 to 6 C atoms, each of which may be substituted by one or more radicals R1, or an aromatic or heteroaromatic ring system having 6 to 40, preferably 6 to 30, more preferably 6 to 18 aromatic ring atoms, which may in each case be substituted by one or more radicals R1.

[0056] When the group R stands for an aromatic or heteroaromatic ring system, this is on each occurrence, identically or differently, preferably selected from the group consisting of phenyl, biphenyl, terphenyl, quaterphenyl, fluorene, spirobifluorene, naphthalene, indol, benzofuran, benzothiophene, dibenzofuran, carbazole, dibenzothiophene, indenocarbazole, indolocarbazole, pyridine, pyrimidine, pyrazine, pyridazine, triazine, quinoline, quinazoline, benzimidazole, benzimidazobenzimidazole, phenanthrene or triphenylene, each of which may be substituted by one or more substituents R1, preferably non-aromatic substituents R1. Preferred aromatic or heteroaromatic ring systems R are on each occurrence, identically or differently, selected from the same groups as depicted by formulae (Ar-1) to (Ar- 144) above which are substituted by substituents R1instead of R.

[0057] Preferably, Ar is, on each occurrence, identically or differently, an aromatic or heteroaromatic ring system having 6 to 40, preferably 6 to 30, more preferably 6 to 24, even more preferably 6 to 18 aromatic ring atoms, which may in each case also be substituted by one or more radicals R1.

[0058] Preferably, R1is on each occurrence, identically or differently, H, D, F, CN, a straight-chain alkyl or alkoxy group having 1 to 10 C atoms, preferably 1 to 5 C atoms, or branched or cyclic alkyl or alkoxy group having 3 to 10 C atoms, preferably 3 to 6 C atoms, or an aromatic or heteroaromatic ring system having 6 to 18 aromatic ring atoms. The compound of formula (1) and the preferred embodiments may also be partially or fully deuterated.

[0059] Examples of suitable materials of formula (1) are depicted in the following table:

[0060]

[0061] The compound of formula (1) has hole transporting properties and is therefore in general used as a hole transporting compound.

[0062] The inventive composition comprises, in addition to the compound of formula (1), a TADF compound. The TADF compound is defined as a compound having a difference of the lowest excited singlet energy Si and the triplet energy Ti of < 1.0 eV. The difference of the lowest excited singlet energy Si and the triplet energy Ti is determined by quantumchemical calculation, as generally described in the examples of this application.

[0063] In a preferred embodiment of the invention, the difference of the lowest excited singlet energy Si and the triplet energy Ti is < 0.5 eV, more preferably < 0.35 eV, more preferably < 0.25 eV, more preferably < 0.15 eV and most preferably < 0.1 eV.

[0064] In one embodiment of the invention, the TADF compound is used in the inventive composition as an emitting compound. In that embodiment, the composition does in general not comprise an additional emitting compound. An OLED wherein a TADF compound is used as emitting compound is referred to as TADF OLED. Suitable TADF compounds which can be used as emitters are generally known in the art.

[0065] Preferred TADF compounds which can also be used as emitting compounds are the compounds which are described later as fluorescent emitters, provided that they have the required S1-T1 separation. Further preferred TADF compounds which can be used as emitting compounds are compounds, which are substituted with donor groups, such as for example carbazolyl groups, aromatic amines or electron-rich heteroaryl groups, as well as with acceptor groups, such as for example CN or electron-deficient heteroaryl groups. Such compounds are generally known to the skilled person.

[0066] The FWHM (full width at half maximum) of the TADF compound used as the emitter is preferably < 60 nm, more preferably < 50 nm, more preferably < 40 nm and most preferably

[0067] < 30 nm. The measurement of the FWHM is described in the examples section.

[0068] In a further embodiment of the invention, the TADF compound is used in the inventive composition as a sensitizer to transfer energy to the fluorescent emitter. An OLED wherein a TADF compound is used as sensitizer to transfer energy to a fluorescent emitter is referred to as hyperfluorescent OLED. In that embodiment, the composition comprises furthermore a fluorescent emitter, in addition to the compound of formula (1) and the TADF compound.

[0069] Suitable TADF compounds which can be used as sensitizer are shown in the following table. 0£ sz oz

[0070] SI

[0071] 01

[0072]

[0073] For use in a hyperfluorescent OLED, the composition comprises a fluorescent emitter in addition to the TADF compound and the compound of formula (1). Suitable fluorescent emitters for use in hyperfluorescent OLEDs are generally known in the art. Preferred fluorescent emitters are aromatic anthracenamines, aromatic anthracenediamines, aromatic pyrenamines, aromatic pyrenediamines, aromatic chrysenamines or aromatic chrysenediamines. An aromatic anthracenamine is taken to mean a compound in which one diarylamino group is bonded directly to an anthracene group, preferably in the 9-position. An aromatic anthracenediamine is taken to mean a compound in which two diarylamino groups are bonded directly to an anthracene group, preferably in the 9,10-position.

[0074] Aromatic pyrenamines, pyrenediamines, chrysenamines and chrysenediamines are defined analogously thereto, where the diarylamino groups are preferably bonded to the pyrene in the 1-position or in the 1,6-position. Further preferred emitters are indenofluorenamines or indenofluorenediamines, for example in accordance with WO 2006 / 108497 or WO 2006 / 122630, benzoindenofluorenamines or benzoindenofluorenediamines, for example in accordance with WO 2008 / 006449, and dibenzoindenofluorenamines or dibenzoindenofluorenediamines, for example in accordance with WO 2007 / 140847, and the indenofluorene derivatives containing condensed aryl groups which are disclosed in WO 2010 / 012328. Still further preferred emitters are benzanthracene derivatives as disclosed in WO 2015 / 158409, anthracene derivatives as disclosed in WO 2017 / 036573, fluorene dimers connected via heteroaryl groups like in WO 2016 / 150544 or phenoxazine derivatives as disclosed in WO 2017 / 028940 and WO 2017 / 028941. Preference is likewise given to the pyrenarylamines disclosed in WO 2012 / 048780 and WO 2013 / 185871. Preference is likewise given to the benzoindenofluorenamines disclosed in

[0075] WO 2014 / 037077, the benzofluorenamines disclosed in WO 2014 / 106522 and the indenofluorenes disclosed in WO 2014 / 111269 or WO 2017 / 036574, WO 2018 / 007421. Also preferred are the emitters comprising dibenzofuran or indenodibenzofuran moieties as disclosed in WO 2018 / 095888, WO 2018 / 095940, WO 2019 / 076789, WO 2019 / 170572 as well as in WO 2020 / 043657, WO 2020 / 043646 and WO / 2020 / 043640. Preference is likewise given to boron derivatives as disclosed, for example, in WO 2015 / 102118, CN108409769, CN107266484, WO2017195669, US2018069182 as well as in WO 2020 / 208051 , W02021 / 058406, and WO 2021 / 094269.

[0076] Very preferred fluorescent emitters are described in WO 2021 / 090932, more particularly on pages 129 to 133, 157 to 166, 171 to 187, 200 to 211 , 222 to 227, 236 to 252, 255; in WO 2020 / 054676, more particularly on pages 44 to 104; in WO 2020 / 017931 , more particularly on pages 17 to 39; in WO 2020 / 218079, more particularly on pages 64 to 258; in WO 2018 / 212169, more particularly on pages 33 to 42; in WO 2019 / 235452, more particularly on pages 46 to 168; in US 10,249,832, more particularly on pages 19 to 106; and in WO 2021 / 014001 , more particularly on pages 107 to 129.

[0077] Preferably, the fluorescent emitter has an emission peak wavelength between 420-550 nm.

[0078] Preferably, the fluorescent emitter has a full width at half maximum FWHM < 50 nm, preferably FWHM < 40 nmm, more preferably FWHM < 30 nm. The method to determine the FWHM is described in the examples.

[0079] In accordance with a preferred embodiment, the fluorescent emitter is selected from compounds of formula (F-1):

[0080] Formula (F-1)

[0081] R has the meanings defined above;

[0082] Ar30, Ar31, Ar32stand on each occurrence, identically or differently, for a substituted or unsubstituted aromatic or heteroaromatic ring system having 5 to 30 aromatic ring atoms; the optional substituent is preferably selected from the substituents R, as defined above;

[0083] Y30stands for B or N; Y31, Y32, Y33stand on each occurrence, identically or differently, for O, S, C(R°)2, C=O, C=S, C=NR°, C=C(R°)2, Si(R°)2, BR°, NR°, PR0, SO2, SeO2or a chemical bond, with the proviso that if Y30is B, then at least one of the groups Y31, Y32, Y33stands for NR° and if Y30is N, then at least one of the groups Y31, Y32, Y33stands for BR°;

[0084] R° stands on each occurrence, identically or differently, for H, D, F, a straight-chain alkyl group having 1 to 20 , preferably 1 to 10 C atoms or branched or a cyclic alkyl group having 3 to 20, preferably 3 to 10 C atoms, each of which may be substituted by one or more radicals R, where in each case one or more non-adjacent CH2groups may be replaced by O or S and where one or more H atoms may be replaced by D or F, or an aromatic or heteroaromatic ring systems having 5 to 40, preferably 5 to 30, more preferably 6 to 18 aromatic ring atoms, which may in each case be substituted by one or more radicals R, where two adjacent radicals R°, may form an aliphatic or aromatic ring system together, which may be substituted by one or more radicals R, where R has the same definition as above; q is 0 or 1 .

[0085] Preferred fluorescent emitters are compounds of formula (F-1) for which the following applies to the symbols and indices:

[0086] - q = 0; Y30= B; and Y31, Y32= NR°; or

[0087] - q = 0; Y30= B; and Y31, Y32= NR°; or

[0088] - q = 1 ; Y30= N; and Y31, Y32= BR°; Y33= chemical bond.

[0089] Examples for blue fluorescent emitters are shown in the following table. Ċ

[0090] Examples for green fluorescent emitters are shown in the following table.

[0091]

[0092] Examples for red fluorescent emitters are shown in the following table.

[0093]

[0094] The composition of the present invention may comprise further host materials, in particular one or more electron-transporting host materials, preferably exactly one electrontransporting host material. Preferably, the electron-transporting host material is selected from compounds comprising a group selected from substituted or unsubstituted triazines, pyrimidines, lactams, benzimidazoles, quinazolines, quinoxalines, azadibenzofurans, diazadibenzofurans, azadibenzothiophenes, diazadibenzothiophenes, carbolines and triptycenes. When these groups are substituted, they are preferably substituted by one or more substituents R as defined above.

[0095] Preferably, the electron-transporting host material has a LIIMO of < -2.10 eV, preferably a LIIMO of < -2.30 eV, more preferably a LIIMO of < -2.40 eV as determined by quantumchemical calculation. The LIIMO is determined by quantumchemical calculation, as generally described in the examples of this application.

[0096] Preferred electron-transporting host materials are selected from the group consisting of aromatic ketones, aromatic phosphineoxides or aromatic sulfoxides or sulfones, as described e.g. in WO 2004 / 013080, WO 2004 / 093207, WO 2006 / 005627 or WO 2010 / 006680, indolocarbazole derivatives substituted with electron-deficient groups, as described e.g. in WO 2007 / 063754 or WO 2008 / 056746, indenocarbazole derivatives substituted with electron-deficienc groups, as described e.g. in WO 2010 / 136109, WO 2011 / 000455, WO 2013 / 041176 or WO 2013 / 056776, azacarbazole derivatives, as described e.g. in EP 1617710, EP 1617711, EP 1731584 or JP 2005 / 347160, silanes, as described e.g. in WO 2005 / 111172, triazine derivatives, as described e.g. in WO 2007 / 063754, WO 2008 / 056746, WO 2010 / 015306, WO 2011 / 057706, WO 2011 / 060859 or WO 2011 / 060877, lactams, as described e.g. in WO 2011 / 116865 or WO 2011 / 137951. Furthermore, a compound may be used as further host material which does not transport charges when the OLED is operated, as described e.g. in WO 2010 / 108579.

[0097] Preferred electron-transporting host materials are selected from the compounds of the formulae (eTMM1), (eTMM2), (eTMM3), (eTMM4) and / or (eTMM5), ormu a (e ), where the symbols and indices used are as follows:

[0098] X stands on each occurrence, identically or differently, for N or CR6, preferably for N;

[0099] L2is on each occurrence, identically or differently, a single bond or an aromatic or heteroaromatic ring system which has 5 to 24 ring atoms and may be substituted in each case by one or more R7radicals;

[0100] R# is on each occurrence, identically or differently, D, F, CN or an aromatic ring system which has 6 to 24 ring atoms and may be substituted by one or more R6radicals, and two adjacent substituents R# together may form an aromatic, heteroaromatic, aliphatic, heteroaliphatic ring system that may be substituted by one or more R7radicals;

[0101] Y is on each occurrence, identically or differently, N or CR7, with exclusion of the possibility that two adjacent Y are both N;

[0102] V2is O or S;

[0103] R6is on each occurrence, identically or differently, H, D, F, CN, Si(R7)3, Ge(R7)3, a straight-chain alkyl group having 1 to 20 carbon atoms or an alkenyl or alkynyl group having 2 to 20 carbon atoms or a branched or cyclic alkyl group having 3 to 20 carbon atoms, where the alkyl, alkenyl or alkynyl group may in each case be substituted by one or more R7radicals and where one or more nonadjacent CH2 groups may be replaced by Si(R7)2, C=O, NR7, O, S or CONR7, or an aromatic or heteroaromatic ring system which has 5 to 60 ring atoms and may be substituted in each case by one or more R7radicals; it is also possible here for two R6radicals together to form an aromatic, heteroaromatic, aliphatic, or heteroaliphatic ring system;

[0104] Ar5is on each occurrence, identically or differently, an aromatic or heteroaromatic ring system which has 5 to 40 ring atoms and may be substituted by one or more R7radicals;

[0105] R7is on each occurrence, identically or differently, H, D, F, Cl, Br, I, N(R8)2, CN, NO2, OR8, SR8, Si(R8)3, Ge(R8)3, B(OR8)2, C(=O)R8, P(=O)(R8)2, S(=O)R8, S(=O)2R8, OSO2R8, a straight-chain alkyl group having 1 to 20 carbon atoms or an alkenyl or alkynyl group having 2 to 20 carbon atoms or a branched or cyclic alkyl group having 3 to 20 carbon atoms, where the alkyl, alkenyl or alkynyl group may in each case be substituted by one or more R8radicals and where one or more nonadjacent CH2 groups may be replaced by Si(R8)2, C=O, NR8, O, S or CONR8, or an aromatic or heteroaromatic ring system which has 5 to 40 ring atoms and may be substituted in each case by one or more R8radicals; at the same time, two or more R7radicals together may form an aromatic, heteroaromatic, aliphatic or heteroaliphatic ring system;

[0106] R8is on each occurrence, identically or differently, H, D, F or an aliphatic, aromatic or heteroaromatic organic radical, especially a hydrocarbyl radical, having 1 to 20 carbon atoms, in which one or more hydrogen atoms may also be replaced by F; b1 is 0, 1 , 2, 3 or 4; b2 is 0, 1 , 2 or 3.

[0107] Preferred compounds of the formula (eTMM1) are the compounds of the formulae (eTMMIa), (eTMMI b), (eTMMIc), (eTMMId), (eTMMIe) and (eTMMIf), Formula (eTMMIc),

[0108] where the symbols and indices for these formulae are defined as follows:

[0109] W, W1are on each occurrence, identically or differently, O, S, C(RW)2 or N-Ar5;

[0110] Rwis on each occurrence, identically or differently, a straight-chain alkyl group having 1 to 20 carbon atoms or a branched or cyclic alkyl group having 3 to 20 carbon atoms, where one or more hydrogen atoms may be replaced by D, F or CN, or an aromatic or heteroaromatic ring system which has 5 to 40 ring atoms and may be substituted by one or more substituents selected from D, F, CN, a straight-chain alkyl group having 1 to 20 carbon atoms or a branched or cyclic alkyl group having 3 to 20 carbon atoms, where one or more hydrogen atoms in the alkyl group on the aromatic or heteroaromatic ring system may be replaced by D, F or CN; at the same time, the two Rwradicals that bind to the same carbon atom may also form a ring system with one another;

[0111] A is on each occurrence, identically or differently, CR7or N, where not more than two A groups per cycle are N and where A is C when L2is bonded to that position; a3 is on each occurrence, identically or differently, 0, 1, 2, 3 or 4; b3 is on each occurrence, identically or differently, 0, 1, 2 or 3;

[0112] Ring B is derived from an aryl group which has 6 to 20 ring atoms and may be substituted by one or more substituents R#;

[0113] Ring

[0114] L3is an aromatic ring system having 6 to 40 ring atoms or a heteroaromatic ring system having 5 to 40 ring atoms, which may be substituted by one or more R7radicals; and where L2, X, Ar5, R7and R# have the definitions given above.

[0115] Particularly preferred host materials for blue OLEDs are compounds of the following

[0116] (eTMMIc*), Formula (eTMMIc*) where the symbols and indices have the same meanings as defined above and the compound can be partially of fully deuterated. The groups Ar5are preferably on each occurrence, identically or differently, selected from phenyl, meta-biphenyl or N-carbazolyl, each of which may be substituted by one or more substituents R7. Furthermore, it is preferred that exactly one substituent which is bound to the N-carbazolyl group or to Ar5is a triphenylsilyl group. Particularly preferred, the compound of formula (eTMMIc*) comprises a group Ar5which is a phenyl group which is substituted in the meta-position with a triphenylsilyl group.

[0117] Preferred compounds of the formula (eTMM2) are the compounds of the formula (eTMM2a): where Y, V2, L2, R7and a3 have a definition given above, D is deuterium, and a4 is 0, 1 or 2.

[0118] Preferred compounds of the formula (eTMM3) are the compounds of the formula (eTMM3a):

[0119] Formula (eTMM3a) where the symbols and indices for this formula (eTMM3a) are defined as follows:

[0120] W1is on each occurrence, identically or differently, O, S, C(RW)2 or N-Ar5;

[0121] #X is CR or NAr5, preferably NAr5;

[0122] Rwis on each occurrence, identically or differently, a straight-chain alkyl group having 1 to 20 carbon atoms or a branched or cyclic alkyl group having 3 to 20 carbon atoms, where one or more hydrogen atoms may be replaced by D, F or CN, or an aromatic or heteroaromatic ring system which has 5 to 40 ring atoms and may be substituted by one or more substituents selected from D, F, CN, a straight-chain alkyl group having 1 to 20 carbon atoms or a branched or cyclic alkyl group having 3 to 20 carbon atoms, where one or more hydrogen atoms in the alkyl group on the aromatic or heteroaromatic ring system may be replaced by D, F or CN; a3 is on each occurrence, identically or differently, 0, 1 , 2, 3 or 4;

[0123] Ring B is derived from an aryl group which has 6 to 20 ring atoms and may be substituted by one or more substituents R#; and where L2, Ar5and R# have the definitions given above. In compounds of the formula (eTMMIa), W is preferably O or N-Ar5.

[0124] In compounds of the formula (eTMMIa), A is preferably on each occurrence, identically or differently, CR7, where A is C when L2is bonded to that position.

[0125] In compounds of the formula (eTMMIe) or (eTMM3a), W1is preferably O, C(RW)2 or N-Ar5, more preferably N-Ar5.

[0126] In compounds of the formula (eTMMIf), L3is preferably a heteroaromatic ring system which has 9 to 30 ring atoms and may be substituted by one or more R7radicals.

[0127] In a preferred embodiment of the compounds of the formulae (eTMM1), (eTMMIa), (eTMMI b), (eTMMIe), (eTMMId), (eTMMIe), (eTMMIf), (eTMM2), (eTMM2a), (eTMM3), (eTMM3a), (eTMM4) and (eTMM5), R7is on each occurrence, identically or differently, selected from the group consisting of H, D, F, CN, a straight-chain alkyl group having 1 to 20 carbon atoms or a branched or cyclic alkyl group having 3 to 20 carbon atoms, where the alkyl group may in each case be substituted by one or more R8radicals, or an aromatic heteroaromatic ring system which has 5 to 60 ring atoms, preferably 5 to 40 ring atoms, and may be substituted in each case by one or more R8radicals.

[0128] In a particularly preferred embodiment of the compounds of the formulae (eTMM1), (eTMMIa), (eTMMI b), (eTMMIe), (eTMMId), (eTMMIe), (eTMMIf), (eTMM2), (eTMM2a), (eTMM3), (eTMM3a), (eTMM4) or (eTMM5), R7is on each occurrence, identically or differently, selected from the group consisting of H, D or an aromatic or heteroaromatic ring system which has 6 to 30 ring atoms and may be substituted by one or more R8radicals.

[0129] The preparation of the compounds of the formulae (eTMM1), (eTMMIa), (eTMMI b), (eTMMIe), (eTMMId), (eTMMIe), (eTMMIf), (eTMM2), (eTMM2a), (eTMM3), (eTMM3a), (eTMM4) and (eTMM5) is generally known, and some of the compounds are commercially available.

[0130] In a preferred embodiment of the matrix material, the latter is a mixture of deuterated compounds of the invention or compounds of the formulae (eTMM1), (eTMMIa), (eTMMI b), (eTMMIe), (eTMMId), (eTMMIe), (eTMMIf), (eTMM2), (eTMM2a), (eTMM3), (eTMM3a), (eTMM4) or (eTMM5), as described above, where the deuteration level of these compounds is at least 50 mol% to 90 mol%, preferably 70 mol% to 100 mol%. If the matrix material is a deuterated compound, it is possible that the matrix material is a mixture of deuterated compounds of the same chemical structure that differ merely by the level of deuteration.

[0131] Suitable compounds of the formula (eTMM1) are known, for example, from the following publications: W02007 / 077810A1 , W02008 / 056746A1 , W02010 / 136109A1 , WO2011 / 057706A2, WO2011 / 160757A1 , WO2012 / 023947A1 , WO2012 / 048781 A1 , WO2013 / 077352A1 , WO2013147205A1 , WO2013 / 083216A1, WO2014 / 094963A1, W02014 / 007564A1 , W02014 / 015931A1 , W02015 / 090504A2, WO2015 / 105251 A1 , WO2015 / 169412A1 , W02016 / 015810A1 , WO2016 / 013875A1 , W02016 / 010402A1 , WO2016 / 033167A1 , WO2017 / 178311A1 , WO2017 / 076485A1 , WO2017 / 186760A1 , W02018 / 004096A1 , WO2018 / 016742A1 , WO2018 / 123783A1 , WO2018 / 159964A1 , WO2018 / 174678A1 , WO2018 / 174679A1 , WO2018 / 174681 A1 , WO2018 / 174682A1 , WO2019 / 177407A1 , WO2019 / 245164A1 , WO2019 / 240473A1 , W02019 / 017730A1 , WO2019 / 017731 A1 , WO2019 / 017734A1 , WO2019 / 145316A1 , WO2019 / 121458A1 , W02020 / 130381 A1 , W02020 / 130509A1 , W02020 / 169241 A1 , WO2020 / 141949A1 , WO2021 / 066623A1 , W02021 / 101220A1 , W02021 / 037401A1 , W02021 / 180614A1 , WO2021 / 239772A1 , W02022 / 015084A1 , WO2022 / 025714A1 , WO2022 / 055169A1 , EP3575296A1, EP3591728A1, U S2014 / 0361254A 1 , US2014 / 0361268A1, KR20210036304A, KR20210036857A, KR2021147993A, JP2011 / 160367A2 and JP2017 / 107992A2.

[0132] Suitable compounds of the formula (eTMM2) are known, for example, from the following publications: WO2015 / 182872A1 , W02015 / 105316A1 , WO2017 / 109637A1 , W02018 / 060307A1 , WO2018 / 151479A2, WO2018 / 088665A2, WO2018 / 060218A1 , WO2018 / 234932A1 , W02019 / 058200A1 , W02019 / 017730A1 , WO2019 / 017731 A1 , WO2019 / 066282A1 , WO2019 / 059577A1 , WO2020 / 141949A1 , W02020 / 067657A1 , WO2022063744A1, W02022 / 090108A1, WO2022 / 207678A1, WO2023061998A1, KR20170139443A, KR20190036867A, KR2019035308A, KR2021147993A, CN110294753A, CN110437241 A, US2016 / 072078A1 , US2019 / 148646A1.

[0133] Suitable compounds of the formula (eTMM3) are known, for example, from the following publications: W02017 / 160089A1 , W02019 / 017730A1 , WO2019 / 017731 A1 , W02020 / 032424A1.

[0134] Suitable compounds of the formula (eTMM5) are known, for example, from the following publications: WO2015 / 093878A1 , WO2016 / 033167A1 , WO2017 / 183859A1 , WO2017 / 188655A1 , WO2018 / 159964A1. For a combination with the compounds of formula (1) as described above or described as preferred, suitable compounds are in particular those of the formulae (eTMM1), (eTMMIa), (eTMMIb), (eTMMIc), (eTMMId), (eTMMIe), (eTMMIf), (eTMM2) and / or (eTMM2a), as described above or described as preferred, or corresponding compounds in the tables that follow that are covered by these formulae. Particular preference is given here to the compounds of the formulae (eTMM1), (eTMMIa), (eTMMIb), (eTMMIc), (eTMMId), (eTMMIe) and / or (eTMMIf).

[0135] Further examples of suitable host materials of the formulae (eTMM1), (eTMMIa), (eTMMIb), (eTMMIc), (eTMMId), (eTMMIe), (eTMMIf), (eTMM2), (eTMM2a), (eTMM3), (eTMM3a), (eTMM4) and (eTMM5) that can be combined in accordance with the invention with above-detailed compounds of the invention are the structures shown in the following tables.

[0136] o o IT) O IT)

[0137] (N (N

[0138]

[0139]

[0140] Particularly preferred compounds of the formulae (eTMM1), (eTMMIa), (eTMMIb), (eTMMIc), (eTMMId), (eTMMIe), (eTMMIf) and / or (eTMM2), which can be used in combination with the TADF compound and the compound of formula (1) are the compounds E1 to E40 in the following table.

[0141] 15

[0142] 20

[0143] 25

[0144] Examples for matrix materials which are particularly suitable for blue emission are the compounds shown in the following table:

[0145]

[0146] In accordance with a preferred embodiment, the composition comprises at least one, two, three or four (when present) deuterated material(s) selected from the hole-transporting host material of formula (1), the electron-transporting host material, the TADF compound and, when present, the fluorescent emitter. More preferably, the composition comprises at least one, two, three or four (when present) deuterated material selected from the holetransporting host material of formula (1), the electron-transporting host material, the TADF compound and, when present, the fluorescent emitter, where the deuteration degree is equal or superior to 10 %, preferably equal or superior to 30 %, more preferably equal or superior to 60%, even more preferably equal or superior to 90%.

[0147] The deuteration degree (DD) corresponds to the number of deuterium atoms in a compound on the total number of deuterium and protium atoms in the compound in %, as follows:

[0148] DD (%) = (ND * 100) / (Np+ ND) where:

[0149] ND is the number of deuterium atoms in the compound NP is the number of deuterium and protium atoms in the compounds.

[0150] The composition of the present invention may be processed by vapour deposition or from solution. If the compositions are applied from solution, formulations of the composition of the invention comprising at least one further solvent are required. These formulations may, for example, be solutions, dispersions or emulsions. For this purpose, it may be preferable to use mixtures of two or more solvents. The present invention therefore further provides a formulation comprising the composition of the invention and at least one solvent.

[0151] The present invention also provides for the use of the present composition in an organic electronic device, preferably in an emissive layer.

[0152] The organic electronic device is preferably selected from organic integrated circuits (OlCs), organic field-effect transistors (OFETs), organic thin-film transistors (OTFTs), organic electroluminescent devices, organic solar cells (OSCs), organic optical detectors and organic photoreceptors, particular preference being given to organic electroluminescent devices. Particularly preferred organic electroluminescent devices containing the present composition, as described above or described as preferred, are organic light-emitting transistors (OLETs), organic field-quench devices (OFQDs), organic light-emitting electrochemical cells (OLECs, LECs, LEECs), organic laser diodes (O-lasers) and organic light-emitting diodes (OLEDs). OLECs and OLEDs are especially preferred and OLEDs are the most preferred.

[0153] In a particularly preferred embodiment of the present invention, the electronic device is an organic electroluminescent device, most preferably an organic light emitting diode (OLED), containing the composition as described above in the emissive layer (EML). Light emission layer, light-emitting layer and emissive layer are used synonymously here.

[0154] In a particularly preferred embodiment of the present invention, the organic electroluminescent device therefore comprises an anode, a cathode and at least one organic layer comprising at least one light-emitting layer, wherein the at least one lightemitting layer comprises the inventive composition.

[0155] In a very particularly preferred embodiment of the invention, the organic electroluminescent device is an organic light emitting diode comprising an anode, a cathode and at least one organic layer comprising at least one light-emitting layer, wherein the at least one lightemitting layer comprises a composition as described above, namely a composition comprising a hole-transporting host material of formula (1), an electron-transporting host material and a TADF compound, where the light-emission of the emitting layer is generated by the TADF compound. In this case, the light-emitting layer comprises preferably 50% to 99% by volume of a host material comprising the hole-transporting host material of formula (1) and the electron-transporting host material and 1% to 50% by volume, preferably 2% to 20% by volume of the TADF compound, based on the overall composition of the light emitting layer. In another very particularly preferred embodiment of the invention, the organic electroluminescent device is an organic light emitting diode comprising an anode, a cathode and at least one organic layer comprising at least one light-emitting layer, wherein the at least one light-emitting layer comprises a composition as described above, namely a composition comprising a hole-transport host material of formula (1), an electrontransporting host material, a TADF compound as a sensitizer and a fluorescent emitter, where the sensitizer transfers energy to the fluorescent emitter and the fluorescent emitter emits light by fluorescence. In this case, the light-emitting layer comprises preferably 50% to 98.5% by volume of a host material comprising the hole-transporting host material of formula (1) and the electron-transporting host material, 5% to 35% by volume, preferably 10% to 20% by volume of the TADF compound used as a sensitizer, and 0.5% to 10% by volume, preferably 3% to 8% by volume of a fluorescent emitter, based on the overall composition of the light emitting layer.

[0156] If the compounds are processed from solution, preference is given to using the corresponding amounts in % by weight rather than the above-specified amounts in % by volume.

[0157] Apart from the cathode, anode and the emissive layer, an electronic device may comprise further layers. These are selected, for example, from in each case one or more hole injection layers, hole transport layers, hole blocking layers, light-emitting layers, electron transport layers, electron injection layers, electron blocking layers, exciton blocking layers, interlayers, charge generation layers and / or organic or inorganic p / n junctions. However, it should be pointed out that not necessarily every one of these layers need be present.

[0158] The sequence of layers in an organic light emitting diode is preferably as follows: anode / hole injection layer / hole transport layer / electron blocking layer / light-emitting layer / hole blocking layer / electron transport layer / electron injection layer / cathode. This sequence of the layers is a preferred sequence. At the same time, it should be pointed out again that not all the layers mentioned need be present and / or that further layers may additionally be present.

[0159] An organic light emitting diode of the invention may contain two or more light-emitting layers. According to the invention, at least one of the light-emitting layers contains a compositions as described above. More preferably, these emission layers in this case have several emission maxima between 380 nm and 750 nm overall, such that the overall result is white emission; in other words, various emitting compounds which may fluoresce or phosphoresce and which emit blue or yellow or orange or red light are used in the lightemitting layers. Especially preferred are three-layer systems, i.e. systems having three light-emitting layers, where the three layers show blue, green and orange or red emission (for the basic construction see, for example, WO 2005 / 011013).

[0160] Suitable charge transport materials for use in the hole injection or hole transport layer or electron blocking layer or electron transport layer of the organic electroluminescent device of the invention are, for example, the compounds disclosed in Y. Shirota et al., Chem. Rev. 2007, 107(4), 953-1010, or other materials as used in these layers according to the prior art.

[0161] Materials used for the electron transport layer may be any materials as used according to the prior art as electron transport materials in the electron transport layer. Especially suitable are aluminium complexes, for example Alqs, zirconium complexes, for example Zrq4, benzimidazole derivatives, triazine derivatives, pyrimidine derivatives, pyridine derivatives, pyrazine derivatives, quinoxaline derivatives, quinoline derivatives, oxadiazole derivatives, aromatic ketones, lactams, boranes, diazaphosphole derivatives and phosphine oxide derivatives. Further suitable materials are derivatives of the abovementioned compounds, as disclosed in JP 2000 / 053957, WO 2003 / 060956, WO 2004 / 028217, WO 2004 / 080975 and WO 2010 / 072300.

[0162] Preferred hole transport materials which can be used in a hole transport, hole injection or electron blocking layer, are selected from indenofluoreneamine derivatives (for example according to WO 06 / 122630 or WO 06 / 100896), the amine derivatives disclosed in EP 1661888, hexaazatriphenylene derivatives (for example according to WO 01 / 049806), amine derivatives having fused aromatic systems (for example according to US 5,061,569), the amine derivatives disclosed in WO 95 / 09147, monobenzoindenofluoreneamines (for example according to WO 08 / 006449), dibenzoindenofluoreneamines (for example according to WO 07 / 140847), spirobifluoreneamines (for example according to WO 2012 / 034627 or WO 2013 / 120577), fluoreneamines (for example according to WO 2014 / 015937, WO 2014 / 015938 and WO 2014 / 015935), spirodibenzopyranamines (for example according to WO 2013 / 083216) and dihydroacridine derivatives (for example WO 2012 / 150001).

[0163] In a further preferred embodiment, the organic electronic device comprising the composition of the invention is characterized in that one or more organic layers comprising the composition of the invention are coated by a sublimation method. In this case, the materials are applied by vapour deposition in vacuum sublimation systems at an initial pressure of less than 10'5mbar, preferably less than 10'6mbar. It is also possible that the initial pressure is even lower, for example less than 10'7mbar.

[0164] Preference is likewise given to an organic electroluminescent device, characterized in that one or more layers are coated by the OVPD (organic vapour phase deposition) method or with the aid of a carrier gas sublimation. In this case, the materials are applied at a pressure between 10'5mbar and 1 bar. A special case of this method is the OVJP (organic vapour jet printing) method, in which the materials are applied directly by a nozzle and thus structured (for example, M. S. Arnold et al., Appl. Phys. Lett. 2008, 92, 053301).

[0165] Preference is additionally given to an organic electroluminescent device, characterized in that one or more organic layers comprising the composition of the invention are produced from solution, for example by spin-coating, or by any printing method, for example screen printing, flexographic printing, nozzle printing or offset printing, but more preferably LITI (light-induced thermal imaging, thermal transfer printing) or inkjet printing. For this purpose, soluble compounds of the components of the composition of the invention are needed. High solubility can be achieved by suitable substitution of the corresponding compounds.

[0166] In addition, hybrid methods are possible, in which, for example, one or more layers are applied from solution and one or more further layers are applied by vapour deposition.

[0167] These methods are known in general terms to those skilled in the art and can be applied to organic electroluminescent devices.

[0168] The invention therefore further provides a process for producing an organic electronic device comprising a composition of the invention as described above or described as preferred, characterized in that at least one organic layer comprising a composition of the invention is applied by gas phase deposition, especially by a sublimation method and / or by an OVPD (organic vapour phase deposition) method and / or with the aid of carrier gas sublimation, or from solution, especially by spin-coating or by a printing method.

[0169] In the production of an organic electronic device by means of gas phase deposition, there are two methods in principle by which an organic layer which is to comprise the composition of the invention and which may comprise multiple different constituents can be applied, or applied by vapour deposition, to any substrate. Firstly, the materials used can each be initially charged in a material source and ultimately evaporated from the different material sources ("co-evaporation"). Secondly, the various materials can be premixed (premix systems) and the mixture can be initially charged in a single material source from which it is ultimately evaporated ("premix evaporation"). In this way, it is possible in a simple and rapid manner to achieve the vapour deposition of a layer with homogeneous distribution of the components without a need for precise actuation of a multitude of material sources.

[0170] The invention accordingly further provides a process characterized in that the composition as described above or described as preferred is deposited from the gas phase successively or simultaneously from at least two material sources, optionally with other materials as described above or described as preferred, and form the organic layer.

[0171] The invention accordingly further provides a process characterized in that the composition of the invention as described above or described as preferred is utilised as material source for the gas phase deposition of the host system and, optionally together with further materials, forms the organic layer.

[0172] The invention further provides a process for producing an organic electronic device comprising a composition of the invention as described above or described as preferred, characterized in that the formulation of the invention as described above is used to apply the organic layer.

[0173] It should be pointed out that variations of the embodiments described in the present invention are covered by the scope of this invention. Any feature disclosed in the present invention may, unless this is explicitly ruled out, be exchanged for alternative features which serve the same purpose or an equivalent or similar purpose. Any feature disclosed in the present invention, unless stated otherwise, should therefore be considered as an example from a generic series or as an equivalent or similar feature. All features of the present invention may be combined with one another in any manner, unless particular features and / or steps are mutually exclusive. This is especially true of preferred features of the present invention. Equally, features of non-essential combinations may be used separately (and not in combination). The technical teaching disclosed with the present invention may be abstracted and combined with other examples. The invention is illustrated in more detail by the examples which follow, without any intention of restricting it thereby.

[0174] Examples

[0175] Determination of HOMO, LUMO, Si and Ti

[0176] The energy levels of molecular orbitals, like the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO), and of the lowest triplet state T1 or of the lowest excited singlet state S1 of materials are determined via quantum-chemical calculations. For all quantum-chemical calculations, the Gaussian program package is used (Gaussian16). The singlet ground state geometries are optimized at the B3LYP / 6-31G(d) level of theory. Subsequently, TD-DFT singlet and triplet excitation energies (vertical transitions) are computed using the optimized ground state geometry and the same method (B3LYP / 6-31G(d)). Default settings for SCF and geometry convergence are employed.

[0177] The energy calculation gives the HOMO energy level HEh or LIIMO energy level LEh in hartree units. The HOMO and LIIMO energy levels in electron volts calibrated with reference to cyclic voltammetry measurements are determined therefrom as follows: HOMO(eV) = (HEh*0.90603) - 0.84836 LUMO(eV) = (LEh*0.99687) - 0.72445 For the purposes of this application, these values are to be regarded as HOMO and LIIMO energy levels respectively of the materials.

[0178] The lowest triplet state T1 is defined as the energy of the triplet state having the lowest energy which arises from the quantum-chemical calculation described.

[0179] The lowest excited singlet state S1 is defined as the energy of the excited singlet state having the lowest energy which arises from the quantum-chemical calculation described. The method described herein is independent of the software package used and always gives the same results. Examples of frequently used programs for this purpose are "Gaussian16" (Gaussian Inc.) and Q Chem 4.1 (Q Chem, Inc.).

[0180] Measurement of FWHM

[0181] The optical bandwidth of a light source is measured by its full width at half maximum (FWHM). The term FWHM refers to the width of an optical signal at half its maximum intensity. FWHM of the fluorescent emitter is determined here at the peak emission wavelength Xmax, which corresponds to the wavelength of the first maximum of the emission spectrum. To determine the peak emission wavelength of the fluorescent emitter, the fluorescent emitter is dissolved in toluene and a photoluminescent spectrum is obtained using a fluorescence spectrometer. More specifically, a concentration of 1 mg / 100 mL is used. The solution is excited in a fluorescence spectrometer, for example Hitachi F-4500. Typically, the first maximum is also the global maximum of the spectrum. To determine the FWHM of the fluorescent emitter, the wavelengths values at half the maximum of the peak emission wavelength, are subtracted.

[0182] OLED Examples

[0183] The following section discloses examples of OLED devices according to preferred embodiments of the invention. The production of OLEDs in general has already been described in the literature, for example in WO 2004 / 058911. The process is adapted to the circumstances as described below, i.e., layer-thickness variation, layer sequences, and materials.

[0184] All exemplary OLED devices are characterised by the following ordered layer structure: Glass plate (hereafter also glass substrate, or substrate), Indium tin oxide (hereafter ITO), Hole injection layer (hereafter HIL) Hole transporting layer (hereafter HTL), Electron blocking layer (hereafter EBL), Emissive layer (hereafter EML), Hole blocking layer (hereafter HBL), Electron transporting layer (hereafter ETL), Electron injection layer (hereafter EIL),

[0185] - Aluminium (hereafter cathode).

[0186] The glass substrates with the structured 50 nm thick ITO are pre-treated with an oxygen plasma, followed by an argon plasma. Hereafter, the materials for the HIL, HTL, EBL, EML, HBL, ETL, and EIL are deposited onto the pre-treated glass substrate by thermal vapor deposition inside a vacuum chamber. Detailed information about the HIL, HTL, EBL, EML, HBL, ETL, and EIL of the OLED device examples is given in Tables 1 & 2. The materials used in these examples are listed in Table 3. Lastly, the cathode is formed by an aluminium layer with a thickness of 100 nm.

[0187] According to an embodiment of the invention, the EML comprises a hole-transporting host material, an electron-transporting host material, a material with TADF properties and a fluorescent dopant. All materials of the EML are deposited at a certain deposition rate in parallel, i.e., by co-evaporation, in order to form a (homogenous, amorphous) mixture. The deposition rate of each material can be chosen such that each material is present in the mixture to a certain volume fraction (Vol.-%). For instance, the composition of an EML comprising a hole-transporting host material denoted as HH with 45 Vol.-%, an electrontransporting host material denoted as EH with 42 Vol.-%, a material with TADF properties denoted as TADF with 10 Vol.-% and a fluorescent dopant denotated as D with 3 Vol.-% is hereafter denoted as HH:EH:TADF:D (45%:42%:10%:3%) in Tables 1 & 2. This notation convention is analogously adapted to describe the composition of an EML that comprises two or three different materials, and also to the HIL, HTL, EBL, HBL, ETL, and EIL of the OLED device in case they comprise more than one material. The performance of the OLED devices can be measured by standard methods. For this purpose, the electroluminescence (EL) spectra and the power efficiency (EffP) can be determined from current / voltage / luminance characteristic lines (l-ll-L characteristic lines) assuming a Lambertian emission profile. The EL spectra can be recorded at a luminous density of 1000 cd / m2and the CIE 1931 x- and y-coordinates can be calculated from the EL spectrum. The operating voltage U is defined as the voltage, which is required for a current density of 10 mA / cm2. The power efficiency EffP is defined as the ratio of the emitted luminous flux of the OLED device measured in Lumen (Im) to the applied electric power measured in Watt (W) at a luminous density of 1000 cd / m2. The lifetime LT90 is defined as the time after which the luminance of the OLED device drops to 90% of the starting luminance in the course of operation with a constant current density of 5 mA / cm2.

[0188] The following examples B1, B2, B3, B4, G1, G2 and G3 correspond to examples according to the invention. BStA1, BStA2 und GStA are OLED devices according to the state of the art. For each inventive example, the power efficiency (EffP), the operating voltage (U) and the device lifetime (LT) is given as relative power efficiency (Rel. EffP), relative operating voltage (Rel. U) and relative device lifetime (Rel. LT) with respect to the corresponding comparative example according to the state of the art, which has a Rel. EffP of 100%, a Rel. U of 100% and a Rel. LT of 100%. The details of the respective HIL, HTL, EBL, EML, HBL, ETL, and EIL are given in Tables 1 & 2. The molecular structures of the materials are given in Table 3.

[0189] Examples B1, B2, B3: The inventive examples B1 , B2 and B3 can be compared to an OLED device as specified by the example BStA1 from Table 1. The EML of these OLED devices comprises a hole-transporting host material, an electron-transporting host material E-1, a material with TADF properties TADF-1 and a fluorescent dopant D-1. The devices differ with regard to the hole-transporting host material that is used in the respective EML, i.e., BH-1 in the case of the state of the art BStA1, BH-2 in the case of example B1 , BH-3 in the case of example B2, and BH-4 in the case of example B3. The OLED devices according to examples B1, B2 and B3 show a superior lifetime (LT90), a superior power efficiency (EffP) and a superior operating voltage (U) compared to the OLED device according to the state of the art BStA1.

[0190] Example B4: The inventive example B4 can be compared to an OLED device as specified by the example BStA2 from Table 1. The EML of these OLED devices comprises a holetransporting host material, a material with TADF properties TADF-1 and a fluorescent dopant D-1. The devices differ with regard to the hole-transporting host material that is used in the respective EML, i.e., BH-1 in the case of the state of the art BStA1 and BH-2 in the case of example B4. The OLED device according to example B4 shows a superior lifetime (LT90), a superior power efficiency (EffP) and a superior operating voltage (II) compared to the OLED device according to the state of the art BStA2.

[0191] Table 1 : Composition and device performance of the blue OLED devices

[0192] Examples G1, G2, G3: The inventive examples G1 , G2 and G3 can be compared to an OLED device as specified by the example GStA1 from Table 2. The EML of these OLED devices comprises a hole-transporting host material, an electron-transporting host material E-2, a material with TADF properties TADF-2 and a fluorescent dopant D-2. The devices differ with regard to the hole-transporting host material that is used in the respective EML, i.e., GH-1 in the case of the state of the art GStAI, GH-2 in the case of example G1 , GH-3 in the case of example G2, and GH-4 in the case of example G3. The OLED devices according to examples G1, G2 and G3 show a superior lifetime (LT90), a superior power efficiency (EffP) and a superior operating voltage (U) compared to the OLED device according to the state of the art GStA1.

[0193] Table 2: Composition and device performance of the green OLED devices

[0194] Table 3: Structural formulae of OLED materials

Claims

Claims1. Composition comprising:(1) a compound having a difference of the lowest excited singlet energy and the triplet energy of < 1.0 eV (TADF compound); and(2) a compound of formula (1):Formula (1) where the symbols and indices used are as follows:M is Si or Ge;X is on each occurrence, identically or differently, CR or N, with the proviso that not more than two X per cycle are N;RM1, RM2are on each occurrence, identically or differently, a straight-chain alkyl group having 1 to 20 C atoms or branched or a cyclic alkyl group having 3 to 20 C atoms where one or more H atoms of the straight-chain, branched or cyclic alkyl group may be replaced by D or F, or an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, which may be substituted by one or more radicals R; the radicals RM1and RM2may be linked to one another and form a mono- or polycyclic aromatic or heteroaromatic ring system, which may be substituted by one or more radicals R;RN1, RN2are on each occurence, identically or differently, an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, which may in each case be substituted by one or more radicals R;when n = m = 1 , the radicals RN1and RM1and / or RN2and RM2may be linked to one another and form a mono- or polycyclic aromatic or heteroaromatic ring system, which may be substituted by one or more radicals R; and when n = 2, two radicals RN1and / or two radicals RN2may be linked to one another and form a mono- or polycyclic aromatic or heteroaromatic ring system, which may be substituted by one or more radicals R;R is on each occurrence, identically or differently, H, D, F, Cl, Br, I, OH, CHO, CN, C(=O)Ar, P(=O)(Ar)2, S(=O)Ar, S(=O)2Ar, N(R1)2, N(Ar)2, NO2, Si(R1)3, Ge(R1)3, B(OR1)2, OSO2R , a straight-chain alkyl, alkoxy or thioalkyl group having 1 to 40 C atoms or branched or a cyclic alkyl, alkoxy or thioalkyl group having 3 to 40 C atoms, each of which may be substituted by one or more radicals R1, where in each case one or more non-adjacent CH2groups may be replaced by R1C=CR1, C=C, Si(R1)2, Ge(R1)2, C=O, P(=O)(R1), SO, SO2, O, S or CONR1and where one or more H atoms may be replaced by D, F, Cl, Br, I, CN or NO2, an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, which may in each case be substituted by one or more radicals R1, or an aryloxy group having 5 to 60 aromatic ring atoms, which may be substituted by one or more radicals R1; where two radicals R may form a mono- or polycyclic, aliphatic ring system, aromatic or heteroaromatic ring system, which may be substituted by one or more radicals R1;Ar is, on each occurrence, identically or differently, an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, which may in each case also be substituted by one or more radicals R1;R1is on each occurrence, identically or differently, H, D, F, Cl, Br, I, CN, a straightchain alkyl, alkoxy or thioalkyl group having 1 to 20 C atoms or branched or cyclic alkyl, alkoxy or thioalkyl group having 3 to 20 C atoms, where in each case one or more non-adjacent CH2groups may be replaced by SO, SO2, O, S and where one or more H atoms may be replaced by D, F, Cl, Br or I, or an aromatic or heteroaromatic ring system having 5 to 24 aromatic ring atoms; n is 1 or 2; m is (2-n) and the composition does not comprise a metal complex.

2. Composition according to claim 1 wherein the compound of formula (1) selected from the compounds of formula (2) and formula (3):Formula (2) Formula (3) where M is Si and the other symbols have the meaning as defined in claim 1.

3. Composition according to claim 1 or 2 wherein the compound of formula (1) selected from the compounds of formulae (2-1) and (3-1),where the symbols have the meaning as defined in claim 1.

4. Composition according to one or more of claims 1 to 3, characterised in that RN1, RN2, RM1and / or RM2are on each occurrence, identically or differently, selected from phenyl, biphenyl, terphenyl, quaterphenyl, fluorene, spirobifluorene, naphthalene, indol, benzofuran, benzothiophene, dibenzofuran, carbazole, dibenzothiophene, indenocarbazole, indolocarbazole, pyridine, pyrimidine, pyrazine, pyridazine, triazine, quinoline, quinazoline, benzimidazole, benzimidazobenzimidazole, phenanthrene or triphenylene, each of which may be substituted by one or more substituents R, preferably non-aromatic substituents R.

5. Composition according to one or more of claims 1 to 4, characterised in that the compound of formula (1) and / or the TADF compound are partially or fully deuterated.

6. Composition according to one or more of claims 1 to 5, characterised in that difference of the lowest excited singlet energy Si and the triplet energy Ti of the TADF compound is < 0.5 eV.

7. Composition according to one or more of claims 1 to 6, characterised in that the composition further comprises a fluorescent emitter.

8. Composition according to claim 7, characterised in that the fluorescent emitter is selected from aromatic anthraceneamines, aromatic anthracenediamines, aromatic pyreneamines, aromatic pyrenediamines, aromatic chryseneamines, aromatic chrysenediamines, indenofluoreneamines, indenofluorenediamines, benzoindeno- fluoreneamines, benzoindenofluorenediamines, dibenzoindenofluoreneamines, dibenzoindenofluorenediamines, or compounds according to the formula (F-1),Formula (F-1 )R has the meanings as defined in claim 1 ;Ar30, Ar31, Ar32are on each occurrence, identically or differently, a substituted or unsubstituted aromatic or heteroaromatic ring system having 5 to 30 aromatic ring atoms wherein the optional substituent is selected from the substituents R;Y30is B or N;Y31, Y32, Y33is on each occurrence, identically or differently, O, S, C(R°)2, C=O, C=S, C=NR°, C=C(R°)2, Si(R°)2, BR°, NR°, PR0, SO2, SeO2or a chemical bond, with the proviso that if Y30is B, then at least one of the groups Y31, Y32, Y33stands for NR° and if Y30is N, then at least one of the groups Y31, Y32, Y33stands for BR°;R° is on each occurrence, identically or differently, H, D, F, a straight-chain alkyl group having 1 to 20 C atoms or branched or a cyclic alkyl group having 3 to 20 Catoms, each of which may be substituted by one or more radicals R, where in each case one or more non-adjacent CH2 groups may be replaced by O or S and where one or more H atoms may be replaced by D or F, or an aromatic or heteroaromatic ring systems having 5 to 40 aromatic ring atoms, which may in each case be substituted by one or more radicals R, where two adjacent radicals R°, may form an aliphatic or aromatic ring system together, which may be substituted by one or more radicals R; q is O or l .

9. Composition according to one or more of claims 1 to 8, characterised in that the composition comprises further an electron-transporting material, which is employed as a host material and which is selected from compounds comprising a group selected from substituted or unsubstituted triazines, pyrimidines, lactams, benzimidazoles, quinazolines, quinoxalines, azadibenzofurans, diazadibenzofurans, azadibenzothiophenes, diazadibenzothiophenes, carbolines and triptycenes wherein the optional substituents are selected from R as defined in claim 1 and wherein the compound is optionally partially of fully deuterated.

10. Composition according to claim 9 characterised in that the electron-transporting material is selected from the compounds of the formulae (eTMM1), (eTMM2), (eTMM3), (eTMM4) and / or (eTMM5),where the symbols and indices used are as follows:X is on each occurrence, identically or differently, N or CR6;L2is on each occurrence, identically or differently, a single bond or an aromatic or heteroaromatic ring system which has 5 to 24 ring atoms and may be substituted in each case by one or more R7radicals;R# is on each occurrence, identically or differently, D, F, CN or an aromatic ring system which has 6 to 24 ring atoms and may be substituted by one or more R6radicals, and two adjacent substituents R# together may form an aromatic, heteroaromatic, aliphatic, heteroaliphatic ring system that may be substituted by one or more R7radicals;Y is on each occurrence, identically or differently, N or CR7, with exclusion of the possibility that two adjacent Y are both N;V2is O or S;R6is on each occurrence, identically or differently, H, D, F, CN, Si(R7)3, Ge(R7)3, a straight-chain alkyl group having 1 to 20 carbon atoms or an alkenyl or alkynyl group having 2 to 20 carbon atoms or a branched or cyclic alkyl group having 3 to 20 carbon atoms, where the alkyl, alkenyl or alkynyl group may in each case be substituted by one or more R7radicals and where one or more nonadjacent CH2 groups may be replaced by Si(R7)2, C=O, NR7, O, S or CONR7, or an aromatic or heteroaromatic ring system which has 5 to 60 ring atoms and may be substituted in each case by one or more R7radicals; it is also possible here for two R6radicals together to form an aromatic, heteroaromatic, aliphatic, or heteroaliphatic ring system;Ar5is on each occurrence, identically or differently, an aromatic or heteroaromatic ring system which has 5 to 40 ring atoms and may be substituted by one or more R7radicals;R7is on each occurrence, identically or differently, H, D, F, Cl, Br, I, N(R8)2, CN, NO2, OR8, SR8, Si(R8)3, Ge(R8)3, B(OR8)2, C(=O)R8, P(=O)(R8)2, S(=O)R8, S(=O)2R8, OSO2R8, a straight-chain alkyl group having 1 to 20 carbon atoms or an alkenyl or alkynyl group having 2 to 20 carbon atoms or a branched or cyclic alkyl group having 3 to 20 carbon atoms, where the alkyl, alkenyl or alkynyl group may in each case be substituted by one or more R8radicals and where one or more nonadjacent CH2 groups may be replaced by Si(R8)2, C=O, NR8, O, S or CONR8, or an aromatic or heteroaromatic ring system which has 5 to 40 ring atoms and may be substituted in each case by one or more R8radicals; at the same time, two or more R7radicals together may form an aromatic, heteroaromatic, aliphatic or heteroaliphatic ring system;R8is on each occurrence, identically or differently, H, D, F or an aliphatic, aromatic or heteroaromatic organic radical, especially a hydrocarbyl radical, having 1 to 20 carbon atoms, in which one or more hydrogen atoms may also be replaced by F; b1 is 0, 1 , 2, 3 or 4; b2 is 0, 1 , 2 or 3.11 . Formulation comprising at least one compound according to one or more of claims 1 to 10 and at least one solvent.

12. Use of a composition according to one or more of claim 1 to 10 in an organic electronic device.

13. Organic electronic device comprising at least one composition according to one or more of claims 1 to 10.

14. Organic electronic device according to claim 13 wherein the device is an organic electroluminescent device and the composition according to one or more of claims 1 to 10 is used in an emitting layer.

15. Process for producing an organic electronic device according to claim 13 or 14, characterised in that at least one organic layer comprising a composition according to one or more of claims 1 to 10 is applied by gas phase deposition and / or by an OVPD (organic vapour phase deposition) method and / or with the aid of carrier gas sublimation or by spin-coating and / or by a printing method.

16. Process for producing an organic electronic device according to claim 15 wherein the components of the composition according to one or more of claims 1 to 10 are deposited from the gas phase successively or simultaneously from at least two material sources, optionally with other materials, and form the organic layer or in that they are deposited as a mixture from the same material source.

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