KR102666621B1 - Formulation of organic functional materials - Google Patents

Abstract

The present invention relates to a formulation containing at least one organic functional material and at least a first organic solvent, wherein the first organic solvent is isosorbide, a derivative or stereoisomer thereof, and is prepared using such formulation. It is about electronic devices.

Description

Formulation of organic functional materials

The present invention relates to formulations containing substituted isosorbides as the first solvent, and to electroluminescent devices made using such formulations.

Organic light emitting devices (OLEDs) have long been fabricated by vacuum deposition processes. Other technologies, such as inkjet printing, have recently been thoroughly investigated due to their advantages such as cost savings and scale-up potential. One of the main difficulties in multilayer printing is identifying the relevant parameters to obtain a uniform deposition of ink on the substrate. To trigger these parameters, such as surface tension, viscosity or boiling point, some additives may be added to the formulation.

Many solvents have been proposed in organic electronic devices for inkjet printing. However, the number of important parameters that play a role during the deposition and drying process makes the choice of solvent very difficult. Therefore, formulations containing organic semiconductors used for film deposition by inkjet printing still require improvement. One object of the present invention is to provide a formulation of an organic semiconductor that allows controlled deposition to form an organic semiconductor layer with good layer properties and efficiency performance. A further object of the present invention is to provide a formulation of an organic semiconductor that provides good layer properties and efficiency performance by enabling uniform application of ink droplets on a substrate, for example when used in inkjet printing methods. will be.

The above objects of the present invention are solved by providing a formulation comprising a substituted isosorbide as the first solvent.

The use of organic solvents containing substituted isosorbides as first solvents allows complete control of the surface tension and leads to effective ink deposition, resulting in highly uniform and well-defined functional materials with good layer properties and performance. forms an organic layer. Since this type of solvent is available from renewable raw materials (saccharides), it is also a sustainable source of printed OLED ink. If additional solvents, preferably additional organic solvents, are used in combination with the first solvent, improved wetting of the already-prepared underlying layer, better shelf life-stability and post-drying of the prepared formulation. Particularly advantageous technical effects, such as improving the film profile of the resulting layer, is observed. Details regarding preferred combinations of solvents, preferred compositions and their concentration ranges and their technical effects are described below.

Figure 1 shows a programmed printing pattern of nine small single droplets positioned in a 3 x 3 matrix.
Figure 2 shows a single droplet merged from all single droplets.
Figure 3 shows a schematic diagram of the droplet of Figure 2.
Figure 4 shows the surface profile, i.e. surface height [nm], as a function of distance x [μm] before (dotted line) and after solvent exposure (solid line).
Figure 5 illustrates the determination of the peak-to-valley of the surface profile as a key performance indicator (KPI) for qualification of layer stability. The solid line represents the surface profile after solvent exposure and vacuum drying.
Figure 6 shows how the KPI according to Figure 5 is assigned to a impairment indicator (DI).

Detailed Description of Embodiments

The present invention relates to a formulation containing at least one organic functional material and at least a two-fold substituted isosorbide as a first solvent. Isosorbide is well known to be a heterocyclic compound derived from glucose and other saccharides depending on the stereoisomerism in question.

Preferred Embodiment

In a first preferred embodiment, the first organic solvent is a compound according to the general formula (I) and/or a stereoisomer thereof:

In the expression

X is, on each occurrence, identically or differently, O or N, preferably both Xs are the same and very preferably both

Y is, on each occurrence, identically or differently, S, NR ⁵ , O, preferably both Ys are the same and very preferably both Ys are O;

R ¹ and R ²

is the same or different in each case and is a linear, branched or cyclic aliphatic group having 1 to 40 aliphatic carbon atoms, preferably 1 to 20 aliphatic carbon atoms, wherein one CH ₂ group or more non-adjacent CH ₂ groups are -O-, -S-, -NR ⁵ -, -CONR ⁵ -, -CO-O-, -C=O-, -R ⁵ C=CR ⁵ -, -C≡C-, -Si( R ⁵ ) ₂ , -Ge(R ⁵ ) ₂ -, -Sn(R ⁵ ) ₂ -, C=S, C=Se, C=NR ⁵ , P(=O)(R ⁵ ), -SO-, -SO ₂ -), an aryl or heteroaryl group having 1 to 60 aromatic carbon atoms, where the groups may be substituted by one or more R ⁶ ;

R ³ and R ⁴

is the same or different in each case and is H, D, F, Cl, Br, a linear, branched or cyclic aliphatic group having 1 to 40 aliphatic carbon atoms, preferably 1 to 20 aliphatic carbon atoms, wherein one CH ₂ groups or more non-adjacent CH ₂ groups are -O-, -S-, -NR ⁵ -, -CONR ⁵ -, -CO-O-, -C=O-, -R ⁵ C=CR ⁵ - , -C≡C-, -Si(R ⁵ ) ₂ , -Ge(R ⁵ ) ₂ -, -Sn(R ⁵ ) ₂ -, C=S, C=Se, C=NR ⁵ , P(=O )(R ⁵ ), -SO-, -SO ₂ -), an aryl or heteroaryl group having 1 to 60 aromatic carbon atoms, wherein those groups may be substituted by one or more R ⁶ ;

R ⁵

is the same or different in each case and is H, a straight-chain alkyl or alkoxy group having 1 to 20 carbon atoms or a branched or cyclic alkyl or alkoxy group having 3 to 20 carbon atoms (and wherein one or more hydrogen atoms is D , F, Cl, Br, I, CN or NO ₂ ), or an aromatic or heteroaromatic ring system having 2 to 60 carbon atoms in the ring system, and R ⁵ is substituted by one or more R ⁶ may be;

R ⁶

is the same or different in each case and is H, a straight-chain alkyl or alkoxy group having 1 to 20 carbon atoms or a branched or cyclic alkyl or alkoxy group having 3 to 20 carbon atoms (and wherein one or more hydrogen atoms is D , F, Cl, Br, I, CN or NO ₂ ), or an aromatic or heteroaromatic ring system having 2 to 60 carbon atoms in the ring system;

In a preferred embodiment, the substituents R ¹ and R ² are identical.

In another preferred embodiment the substituents R ¹ and R ² are different from each other.

The term aliphatic group is well known to those skilled in the art and is understood to refer to a non-aromatic hydrocarbon group. Preferably, the aliphatic group according to the invention is a saturated aliphatic group. Even more preferably, the aliphatic group is an alkyl group.

Preferably R ¹ and R ² are in each case identical or different a linear, branched or cyclic alkyl group, very preferably having 1 to 40 carbon atoms, preferably 1 to 20 aliphatic carbon atoms. A linear or branched alkyl group having 1 to 40 carbon atoms, preferably 1 to 20 aliphatic carbon atoms, particularly preferably having 1 to 40 carbon atoms, preferably 1 to 20 aliphatic carbon atoms a linear alkyl group, wherein the groups may be substituted with one or more R ⁶ ; And where one CH ₂ group or more non-adjacent CH ₂ groups are -O-, -S-, -NR ⁵ -, -CONR ⁵ -, -CO-O-, -C=O-, -R ⁵ C =CR ⁵ -, -C≡C-, -Si(R ⁵ ) ₂ , -Ge(R ⁵ ) ₂ -, -Sn(R ⁵ ) ₂ -, C=S, C=Se, C=NR ⁵ , may be replaced by P(=O)(R ⁵ ), -SO-, -SO ₂ -; Very preferably one CH ₂ group or more non-adjacent CH ₂ groups are -O-, -S-, -NR ⁵ -, -CONR ⁵ -, -CO-O-, -C=O-, -Si (R ⁵ ) ₂ , C=S, P(=O)(R ⁵ ), -SO- and -SO ₂ -; Particularly preferably one CH ₂ group or more non-adjacent CH ₂ groups may be replaced by -O-, -S- and very particularly preferably one CH ₂ group or more non-adjacent CH ₂ groups may be replaced by -O-, -S- It can also be replaced with -O-.

Preferably the substituents R ¹ and R ² are not further substituted by R ⁶ .

Preferably, R ³ and R ⁴ are in each case identical or different, H, D, F, Cl, I, NO ₂ , CN, a linear, branched or cyclic alkyl group having 1 to 40 carbon atoms ( where one CH ₂ group or more non-adjacent CH ₂ groups are -O-, -S-, -NR ⁵ -, -CONR ⁵ -, -CO-O-, -C=O-, -R ⁵ C=CR ⁵ -, -C≡C-, -Si(R ⁵ ) ₂ , -Ge(R ⁵ ) ₂ -, -Sn(R ⁵ ) ₂ -, C=S, C=Se, C=NR ⁵ , P( =O)(R ⁵ ), -SO-, -SO ₂ -), aryl or heteroaryl groups having 1 to 60 aromatic carbon atoms, wherein the groups are selected from one or more R ⁶ may be substituted; Very preferably one CH ₂ group or more non-adjacent CH ₂ groups are -O-, -S-, -NR ⁵ -, -CONR ⁵ -, -CO-O-, -C=O-, -Si( R ⁵ ) ₂ , C=S, P(=O)(R ⁵ ), -SO- and -SO ₂ -; Particularly preferably one CH ₂ group or more non-adjacent CH ₂ groups may be replaced by -O-, -S- and very particularly preferably one CH ₂ group or more non-adjacent CH ₂ groups may be replaced by -O - may be replaced with .

Very preferably, R ³ is H.

Very preferably, R ⁴ is H.

Particularly preferably, R ³ and R ⁴ are H.

The aliphatic group of R ¹ to R ⁴ has 1 to 40 aliphatic carbon atoms, preferably 1 to 20 aliphatic carbon atoms, very preferably 1 to 10 aliphatic carbon atoms and particularly preferably 1 to 5 aliphatic carbon atoms. Includes.

Preferred alkyl groups of R ¹ to R ⁴ contain 1 to 40 carbon atoms, preferably 1 to 20 carbon atoms, very preferably 1 to 10 carbon atoms and particularly preferably 1 to 5 carbon atoms. .

Preferably, the first atoms of R ¹ and R ² bonded to the group Y of the isosorbide core structure are non-aromatic carbon atoms, whereby the isosorbide core structure is defined to have the structure:

In the context of the present application, a non-aromatic carbon atom is defined as a carbon atom that is not part of an aromatic system.

Preferably, the first atom of both R ³ and R ⁴ bonded to the carbon atom of the isosorbide core structure is H or a non-aromatic carbon atom.

Very preferably, the first atom of R ¹ and R ² bonded to the group Y of the isosorbide core structure is a non-aromatic carbon atom and the first atom of R ³ and R ⁴ bonded to the carbon atom of the isosorbide core structure The atom is H or a non-aromatic carbon atom.

As is commonly understood by those skilled in the art, aliphatic groups are acyclic, i.e. linear or branched, or cyclic, saturated or unsaturated carbon compounds, also called hydrocarbons, excluding aromatic groups.

For the purposes of the present invention, straight-chain aliphatic alkyl groups having 1 to 40 carbon atoms, branched or cyclic aliphatic alkyl groups having 3 to 40 carbon atoms, alkenyl groups having 2 to 40 carbon atoms, or The alkynyl group (and also here individual H atoms or CH ₂ groups may be substituted or replaced by the above-mentioned substituents) is preferably represented by the radicals methyl, ethyl, n-propyl, i-propyl, n-butyl, i -butyl, s-butyl, t-butyl, 2-methylbutyl, n-peptyl, s-peptyl, cycloheptyl, neo-peptyl, n-hexyl, cyclohexyl, neo-hexyl, 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, heptynyl or octynyl.

Aryl groups according to the invention contain at least 6 carbon atoms; Heteroaryl groups according to the invention contain at least two carbon atoms and at least one heteroatom, provided that the total of carbon atoms and heteroatoms is at least five. Heteroatoms are preferably selected from N, O, and/or S. Aryl or heteroaryl groups are herein simple aromatic rings, such as benzene, or simple heteroaromatic rings, such as pyridine, pyrimidine, thiophene, etc., or condensed (fused) aryl or heteroaryl groups, such as naphthalene. , anthracene, pyrene, quinoline, isoquinoline, etc.

An aromatic ring system in the meaning of the present invention contains from 6 to 60 carbon atoms in the ring system, preferably the aromatic ring system contains from 6 to 20 carbon atoms in the ring system. A heteroaromatic ring system in the sense of the present invention contains 5 to 60 aromatic ring atoms, at least one of which is a heteroatom, preferably a heteroaromatic ring system in the meaning of the present invention contains 5 to 20 aromatic ring atoms, at least one of which is a heteroatom. Contains aromatic ring atoms. Heteroatoms are preferably selected from N, O, and/or S. An aromatic or heteroaromatic ring system in the sense of the present invention need not necessarily comprise only aryl or heteroaryl groups, but instead, in addition, a plurality of aryl or heteroaryl groups may be present in non-aromatic units (preferably in addition to H % atoms), such as, for example, by sp ³ hybridized C, Si, N or O atoms, sp ² hybridized C or N atoms or sp hybridized C atoms. It is intended. Thus, for example, systems such as 9,9'-spirobifluorene, 9,9-diarylfluorene, triarylamine, diaryl ether, stilbene, etc. can also be used in the presence of two or more aryl groups, e.g. It is believed to be an aromatic ring system within the meaning of the invention, such as a system linked by an alkyl group, alkenyl, or alkynyl or by a silyl group. Furthermore, ring systems linked to each other by single bonds, such as, for example, biphenyl, terphenyl, or diphenyltriazine, are referred to as aromatic and heteroaromatic ring systems in the meaning of this application.

Aromatic having 5 to 60 aromatic ring atoms, preferably 5 to 20 aromatic ring atoms, which in each case may also be substituted by the above-mentioned substituents and may be linked via any desired position on the aromatic or heteroaromatic group. or heteroaromatic ring systems are, in particular, benzene, naphthalene, anthracene, benzanthracene, phenanthrene, benzophenanthrene, pyrene, chrysene, perylene, fluoranthene, naphthacene, pentacene, benzopyrene, biphenyl, biphenylene. , terphenyl, terphenylene, triphenylene, quarterphenyl, fluorene, spirobifluorene, dihydrophenanthrene, dihydropyrene, tetrahydropyrene, cis- or trans-indenofluorene, truxene, iso Truxen, Spirotruxen, Spiroisotruxen, 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, naphthymidazole, phenanthrimidazole, pyridimidazole, pyrazinimidazole, quinoxaline imidazole, oxazole, benzoxa Sol, naphthoxazole, anthroxazole, phenanthroxazole, isoxazole, 1,2-thiazole, 1,3-thiazole, benzothiazole, pyridazine, benzopyridazine, pyrimidine, benzopyrimidine, quinoc Saline, 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, benzocarboline, phenanthroline, 1,2,3-tria Sol, 1,2,4-triazole, benzotriazole, 1,2,3-oxadiazole, 1,2,4-oxadiazole, 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 or groups derived from combinations of these systems.

Preferred substituents R ¹ and R ² are the following groups having the following formulas (R-1) to (R-24), where the dotted line represents the bond of R ¹ or R ² to group Y of formula (1), where The groups may be substituted with one or more R ⁶ . Preferably the substituents R ¹ and R ² are not further substituted by R ⁶ .

In a particularly preferred embodiment, the substituent R ⁶ is H.

Examples of the most preferred solvates of formula (I) and their boiling points (BP) and melting points (MP) are shown in the table below.

Preferably, the first solvent has a surface tension of ≧20 mN/m. More preferably, the surface tension of the first solvent is in the range of 25 to 40 mN/m.

The content of the first solvent is preferably in the range of 50 to 100 vol.%, more preferably in the range of 75 to 100 vol.% and most preferably in the range of 90 to 100 vol.%, based on the total amount of solvent in the formulation.

In one embodiment, the formulation according to the invention comprises at least a second solvent that is different from the first solvent. The second solvent is used together with the first solvent.

The content of the second solvent is preferably in the range from 0 to 50% by volume, more preferably in the range from 0 to 25% by volume and most preferably in the range from 0 to 10% by volume, based on the total amount of solvent in the formulation.

In another and very preferred embodiment, the formulation comprises said first solvent and second solvent, wherein the content of the first solvent (expressed in % by volume) is lower than the content of the second solvent. Preferably the content of the first solvent ranges from 0.1% by volume to 49% by volume, very preferably from 0.1% by volume to 30% by volume, particularly preferably from 0.5% by volume, based on the total amount of solvents in the formulation. in the range of 20% by volume, very particularly preferably in the range from 1% to 10% by volume and most preferably in the range from 2% to 8% by volume. These formulations are characterized by, inter alia, good long-term stability without precipitation of dissolved active compounds, improved wetting of the substrate or the underlying layer of organic materials, good film formation on drying (dense layer with flat profile) and good stability (such as color, efficiency and lifetime). parameters), it exhibits advantageous technical effects, such as superior performance of the final OLED device.

Even if more than two solvents are used in the formulation, the advantageous technical effects mentioned above can be further improved. Accordingly, the invention also relates to the above-mentioned formulation, comprising said first solvent and said second solvent, wherein the second solvent is a mixture of two different solvents.

In another embodiment, the invention also relates to a formulation comprising said first solvent and said second solvent, wherein the second solvent is a mixture of three different solvents.

In another embodiment, the invention also relates to a formulation comprising said first solvent and said second solvent, wherein the second solvent is a mixture of four different solvents.

Preferably, the first solvent has a boiling point of 400° C. or lower. More preferably, the first solvent has a boiling point in the range from 100 to 400 °C, very preferably in the range from 100 to 350 °C, particularly preferably in the range from 150 to 350 °C, and very particularly preferably in the range from 200 to 350 °C. ℃ range. The boiling point is measured at 760 mm Hg.

Suitable second solvents are preferably, in particular, alcohols, aldehydes, ketones, ethers, esters, amides such as di C ₁ -C _-2 -alkylformamides, sulfur compounds, nitro compounds, hydrocarbons, halogenated hydrocarbons (e.g. It is an organic solvent containing chlorinated hydrocarbons), aromatic or heteroaromatic hydrocarbons, and halogenated aromatic or heteroaromatic hydrocarbons.

Preferably, the second solvent may be selected from one of the following group: substituted and unsubstituted aromatic or linear esters such as ethyl benzoate, butyl benzoate, octyl octanoate, diethyl sebacate; Substituted and unsubstituted aromatic or linear ethers, such as 3-phenoxytoluene, 3,4-dimethylanisole, phenetol or anisole; Substituted or unsubstituted arene derivatives such as toluene, xylene, pentylbenzene, hexylbenzene, cyclohexylbenzene, 2-methylbiphenyl, 2,2'-dimethylbiphenyl; indane derivatives such as hexamethylindane; substituted and unsubstituted aromatic or linear ketones; Substituted and unsubstituted heterocycles such as pyrrolidinone, cyclic or acyclic siloxane, pyridine, pyrazine; Other fluorinated or chlorinated aromatic hydrocarbons.

Particularly preferred second organic solvents are for example 1,2,3,4-tetramethylbenzene, 1,2,3,5-tetramethylbenzene, 1,2,3-trimethylbenzene, 1,2,4,5 -Tetramethylbenzene, 1,2,4-trichlorobenzene, 1,2,4-trimethylbenzene, 1,2-dihydronaphthalene, 1,2-dimethylnaphthalene, 1,3-benzodioxolane, 1,3 -Diisopropylbenzene, 1,3-dimethylnaphthalene, 1,4-benzodioxane, 1,4-diisopropylbenzene, 1,4-dimethylnaphthalene, 1,5-dimethyltetraline, 1-benzothylene Ophene, thianaphthalene, 1-bromonaphthalene, 1-chloromethylnaphthalene, 1-ethylnaphthalene, 1-methoxynaphthalene, 1-methylnaphthalene, 1-methylindole, 2,3-benzofuran, 2,3-di Hydrobenzofuran, 2,3-dimethylanisole, 2,4-dimethylanisole, 2,5-dimethylanisole, 2,6-dimethylanisole, 2,6-dimethylnaphthalene, 2-bromo-3- Bromomethylnaphthalene, 2-bromomethylnaphthalene, 2-bromonaphthalene, 2-ethoxynaphthalene, 2-ethylnaphthalene, 2-isopropylanisole, 2-methylanisole, 2-methylindole, 3,4 -Dimethylanisole, 3,5-dimethylanisole, 3-bromoquinoline, 3-methylanisole, 4-methylanisole, 5-decanolide, 5-methoxyindane, 5-methoxyindole, 5 -tert-butyl-m-xylene, 6-methylquinoline, 8-methylquinoline, acetophenone, anisole, benzonitrile, benzothiazole, benzyl acetate, bromobenzene, butyl benzoate, butyl phenyl ether, cyclohexyl Benzene, decahydronaphthol, dimethoxytoluene, 3-phenoxytoluene, diphenyl ether, propiophenone, ethylbenzene, ethyl benzoate, hexylbenzene, indane, hexamethylindane, indene, isochroman, cumene, m- Cymene, mesitylene, methyl benzoate, o-, m-, p-xylene, propyl benzoate, propylbenzene, o-dichlorobenzene, pentylbenzene, phenethol, ethoxybenzene, phenyl acetate, p-cymene, propylene Ophenone, sec-butylbenzene, t-butylbenzene, thiophene, toluene, veratrol, monochlorobenzene, o-dichlorobenzene, pyridine, pyrazine, pyrimidine, pyrrolidinone, morpholine, dimethylacet-amide, dimethyl sulfoxide, decalin and/or mixtures of these compounds.

As disclosed above, these solvents can be used individually or as a mixture of two, three or more solvents forming a second solvent.

Preferably, the boiling point of the second solvent is in the range of 100 to 400°C, more preferably in the range of 150 to 350°C.

The at least one organic functional material has a solubility in the first and second solvents, preferably in the range from 1 to 250 g/l and more preferably in the range from 1 to 50 g/l. The solubility of organic functional materials in solvents can be determined according to the procedures described in ISO 7579:2009.

The content of at least one organic functional material in the formulation ranges from 0.001 to 20% by weight, preferably from 0.01 to 15% by weight, more preferably from 0.1 to 10% by weight, and most preferably from 0.001 to 20% by weight, based on the total weight of the formulation. ranges from 0.3 to 10% by weight.

The surface tension of the formulation according to the invention is preferably in the range from 10 to 70 mN/m, very preferably in the range from 10 to 50 mN/m and particularly preferably in the range from 15 to 40 mN/m.

Moreover, the formulation according to the invention preferably has a temperature range of 0.8 to 50 mPa·s, very preferably 1 to 40 mPa·s, particularly preferably 2 to 20 mPa·s and very particularly preferably 2 It has a viscosity ranging from 10 mPa·s.

Preferably, the organic solvent blend comprises a surface tension in the range of 15 to 80 mN/m, more preferably in the range of 20 to 60 mN/m and most preferably in the range of 25 to 40 mN/m.

Surface tension can be measured using a FTA (First Ten Angstrom) 1000 contact angle goniometer at 20°C. Details of this method are provided by Roger P. Woodward, Ph.D. Available from First Ten Angstrom, published as "Surface Tension Measurements Using the Drop Shape Method". Preferably, the surface tension can be determined using the pendant drop method. This measurement technique dispenses a drop from a needle in the bulk liquid or vapor phase. The shape of the droplet results from the relationship between surface tension, gravity, and density differences. When using the drop method, the surface tension is calculated from the shadow image of the drop using http://www.kruss.de/services/education-theory/glossary/drop-shape-analysis. Commonly used and commercially available high-precision droplet shape analysis tools, namely First Ten All surface tension measurements were performed using FTA100 from ngstrom. The surface tension is determined by the software FTA1000. All measurements are performed at room temperature ranging from 20°C to 22°C. Standard operating procedures include determination of the surface tension of each formulation using novel disposable droplet dispensing systems (syringes and needles). Each droplet is measured with 60 measurements over a duration of 1 minute, which are later averaged. For each formulation, three droplets were measured. The final value is averaged over the measurements. The tools are regularly cross-checked against various liquids with well-known surface tensions.

The viscosity of the formulations and solvents of the examples was measured using a TA instruments ARG2 rheometer over a shear rate range from 10 to 1000 s ^-1 using a 40 mm parallel plate geometry. Measurements were taken as averages from 200 to 800 s ^-1 , where temperature and shear rate were accurately controlled. The viscosity given in Table 3 is that of each formulation measured at a temperature of 25° C. and a shear rate of 500 s ⁻¹ . Each solvent was measured three times. The viscosity values mentioned are averaged over the above measurements.

The invention also relates to formulations comprising at least one quantum material and isosorbide as the first solvent. The invention also relates to formulations comprising at least one organic functional material and at least one quantum material.

The formulations according to the invention can be used for the production of functional layers of electronic devices.

Functional materials are generally organic materials introduced between the anode and cathode of electronic or optoelectronic devices, especially electroluminescent devices.

Quantum materials are well known to those skilled in the art. Quantum materials are also known as quantum-sized particles, nanocrystalline materials, semiconductor light-emitting nanoparticles, quantum dots, and quantum rods. Quantum materials can be used as photoluminescent materials or electroluminescent materials. In general, quantum materials are characterized by the fact that they exhibit a narrow size distribution and have a narrow emission spectrum.

Quantum materials typically include a core and one or more shell layers, as well as ligands attached to the outermost surface of the material. Preferably, the quantum material has an average particle diameter in the range from 0.1 to 999 nm, very preferably in the range from 1 to 150 nm, and particularly preferably in the range from 3 to 100 nm, wherein the ligand spheres of the quantum material are not taken into account. .

The term organic functional material includes, inter alia, organic conductors, organic semiconductors, organic fluorescent compounds, which also include organic delayed fluorescent compounds, organic phosphorescent compounds, organic light-absorbing compounds, organic photosensitive compounds, organic photosensitizers, organic p-dopants, organic n -Indicates dopants and other organic photoactive compounds. The term organic functional materials therefore includes organometallic complexes of transition metals, rare earths, lanthanides and actinides.

Organic functional materials include fluorescent emitters, phosphorescent emitters, emitters that emit light based on delayed fluorescence, host materials, matrix materials, host materials that exhibit delayed fluorescence, exciton blocking materials, electron transport materials, electron injection materials, and hole transport. The material is selected from the group consisting of hole injection materials, n-dopants, p-dopants, wide-band-gap materials, electron blocking materials, and hole blocking materials.

Preferred embodiments of organic functional materials are disclosed in detail in WO 2011/076314 A1, the content of which is incorporated herein by reference.

In a preferred embodiment, the organic functional material is an organic semiconductor selected from the group consisting of hole injection, hole transport, emission, electron transport and electron injection materials.

More preferably, the organic functional material is an organic semiconductor selected from the group consisting of hole injection and hole transport materials.

The organic functional material may be a compound, polymer, oligomer or dendrimer with low molecular weight, where the organic functional material may also be in the form of a mixture. Therefore, the formulation according to the invention may comprise two different compounds with low molecular weight, one compound with low molecular weight and one polymer or two polymers (blend).

Organic functional materials are often described through the properties of frontier orbitals, which are explained in more detail below. Molecular orbitals, especially also the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO), their energy levels and the energy of the lowest triplet state T ₁ or of the lowest excited singlet state S ₁ of the material are It is determined through quantum-chemical calculations. To calculate metal-free organic materials, first, geometry optimization is performed using the “Ground State/Semi-empirical/Default Spin/AM1/Charge 0/Spin Singlet” method. Energy calculations are subsequently performed based on the optimized geometry. The "TD-SCF/DFT/Default Spin/B3PW91" method with the "6-31G(d)" base set (charge 0, spin singlet) is used here. For metal-containing compounds, the geometry is optimized via the “Ground State/Hartree-Fock/Default Spin/LanL2MB/Charge 0/Spin Singlet” method. Energy calculations are performed similarly to the method described above for organic materials, except that the "LanL2DZ" base set is used for metal atoms and the "6-31G(d)" base set is used for ligands. The energy calculation gives the HOMO energy level HEh or the LUMO energy level LEh in hartree units. The HOMO and LUMO energy levels in electron volts, calibrated based on cyclic voltammetry measurements, are then determined as follows:

HOMO(eV) = ((HEh*27.212)-0.9899)/1.1206

LUMO(eV) = ((LEh*27.212)-2.0041)/1.385

For the purposes of this application, these values will be regarded as the HOMO and LUMO energy levels of the materials, respectively.

The lowest triplet state T ₁ is defined as the energy of the triplet state with the lowest energy resulting from the quantum chemical calculations described.

The lowest excited singlet state S ₁ is defined as the energy of the excited singlet state with the lowest energy resulting from the quantum chemical calculations described.

The method described here is independent of the software package used and will always give the same results. Examples of programs frequently used for this purpose are "Gaussian09W" (Gaussian Inc.) and Q-Chem 4.1 (Q-Chem, Inc.).

Compounds with hole injection properties, also so-called hole injection materials herein, simplify or facilitate the transport of holes, that is, positive charges, from the anode to the organic layer. Typically, the hole injecting material has a HOMO level at or above the anode level region, ie typically at least -5.3 eV.

Compounds with hole transport properties, also so-called hole transport materials herein, are generally capable of transporting holes, i.e. positive charges, injected from the anode or an adjacent layer, for example a hole injection layer. The hole transport material generally preferably has a high HOMO level of at least -5.4 eV. Depending on the structure of the electronic device, hole transport materials may also be used as hole injection materials.

Preferred compounds having hole injection and/or hole transport properties include, for example, triarylamine, benzidine, tetraaryl-para-phenylenediamine, triarylphosphine, phenothiazine, phenoxazine, dihydrophenazine, thiamine. Trene, dibenzo-para-dioxine, phenoxathiine, carbazole, azulene, thiophene, pyrrole and furan derivatives, and additional O-, S- with high HOMO (HOMO = highest occupied molecular orbital) or N-containing heterocycles.

Compounds with hole injection and/or hole transport properties include phenylenediamine derivatives (US 3615404), arylamine derivatives (US 3567450), amino-substituted chalcone derivatives (US 3526501), styrylanthracene derivatives (JP-A- 56-46234), polycyclic aromatic compounds (EP 1009041), polyarylalkane derivatives (US 3615402), fluorenone derivatives (JP-A-54-110837), hydrazone derivatives (US 3717462), acylhydrazone, stilbene derivatives (JP-A-61-210363), silazane derivative (US 4950950), polysilane (JP-A-2-204996), aniline copolymer (JP-A-2-282263), thiophene oligomer (JP Heisei 1 (1989) 211399), polythiophene, poly(N-vinylcarbazole) (PVK), polypyrrole, polyaniline and other electrically conductive macromolecules, porphyrin compounds (JP-A-63-2956965, US 4720432), aromatic dimethylidene type compounds, carbazole compounds, such as for example CDBP, CBP, mCP, aromatic tertiary amines and styrylamine compounds (US 4127412), such as for example triphenylamines of the benzidine type, triphenylamines of the styrylamine type and triphenylamine of the diamine type may be particularly mentioned. Also, arylamine dendrimers (JP Heisei 8 (1996) 193191), monomeric triarylamines (US 3180730), triarylamines containing at least one functional group containing one or more vinyl radicals and/or active hydrogen (US 3567450) and US 3658520), or tetraaryldiamine (two tertiary amine units linked through an aryl group) can be used. Additionally, more triarylamino groups may be present in the molecule. Also suitable are phthalocyanine derivatives, naphthalocyanine derivatives, butadiene derivatives and quinoline derivatives, such as for example dipyrazino[2,3-f:2',3'-h]quinoxalinehexacarbo-nitrile.

Aromatic tertiary amines containing at least two tertiary amine units (US 2008/0102311 A1, US 4720432 and US 5061569), such as for example NPD (α-NPD = 4,4'-bis[N-(1- Naphthyl)-N-phenylamino]biphenyl) (US 5061569), TPD 232 (= N,N'-bis-(N,N'-diphenyl-4-aminophenyl)-N,N-diphenyl- 4,4'-diamino-1,1'-biphenyl) or MTDATA (MTDATA or m-MTDATA = 4,4',4"-tris[(3-methylphenyl)phenylamino]triphenylamine) (JP- A-4-308688), TBDB (= N,N,N',N'-tetra(4-biphenyl)diaminobiphenylene), TAPC (=1,1-bis(4-di-p-tolyl aminophenyl)cyclohexane), TAPPP (= 1,1-bis(4-di-p-tolylaminophenyl)-3-phenylpropane), BDTAPVB (= 1,4-bis[2-[4-[N, N-di(p-tolyl)amino]phenyl]vinyl]benzene), TTB (= N,N,N',N'-tetra-p-tolyl-4,4'-diaminobiphenyl), TPD (= 4,4'-bis[-3-methylphenyl]-N-phenylamino)biphenyl), N,N,N',N'-tetraphenyl-4,4"'-diamino-1,1',4 ',1",4",1"'-quarterphenyl, also tertiary amines containing carbazole units, such as for example TCTA (=4-(9H-carbazol-9-yl)-N,N- Preference is given to hexaazatriphenylene compounds according to US 2007/0092755 A1 and phthalocyanine derivatives (eg H ₂ Pc, CuPc (= copper phthalocyanine), CoPc, NiPc, ZnPc, PdPc, FePc, MnPc, ClAlPc, ClGaPc, ClInPc, ClSnPc, Cl ₂ SiPc, (HO)AlPc, (HO)GaPc, VOPc, TiOPc, MoOPc, GaPc-O-GaPc) is equally desirable.

Particular preference is given to the following triarylamine compounds of formula (TA-1) to (TA-12), which are described in EP 1162193 B1, EP 650 955 B1, Synth.Metals 1997 , 91(13), 209, DE 19646119 A1, WO 2006/122630 A1, EP 1 860 097 A1, EP 1834945 A1, JP 08053397 A, US 6251531 B1, US 2005/0221124, JP 08292586 A, US 7399537 B2 , US 2006/0061265 A1 , EP 1 661 888 and WO 2009/ It is disclosed in 041635. The above compounds of formula (TA-1) to (TA-12) may also be substituted:

Further compounds that can be used as hole injection materials are described in EP 0891121 A1 and EP 1029909 A1, and injection layers are generally described in US 2004/0174116 A1.

These arylamines and heterocycles, which are generally used as hole injection and/or hole transport materials, give rise to a HOMO in the polymer preferably greater than -5.8 eV (relative to the vacuum level), particularly preferably greater than -5.5 eV. .

Compounds with electron injection and/or electron transport properties include, for example, pyridine, pyrimidine, pyridazine, pyrazine, oxadiazole, quinoline, quinoxaline, anthracene, benzanthracene, pyrene, perylene, benzimidazole, triazine Azines, ketones, phosphine oxides and phenazine derivatives, as well as trialrylborane and further O-, S- or N-containing heterocycles with low LUMO (LUMO = lowest unoccupied molecular orbital).

Particularly suitable compounds for electron transport and electron injection layers include metal chelates of 8-hydroxyquinoline (e.g. LiQ, AlQ ₃ , GaQ ₃ , MgQ ₂ , ZnQ ₂ , InQ ₃ , ZrQ ₄ ), BAlQ, Ga oxinoids Complexes, 4-azaphenanthrene-5-ol-Be complex (US 5529853 A, see formula ET-1), butadiene derivative (US 4356429), heterocyclic optical brightener (US 4539507), benzimidazole Derivatives (US 2007/0273272 A1), such as for example TPBI (see US 5766779, formula ET-2), 1,3,5-triazines, for example spirobifluorenyltriazine derivatives (for example DE 102008064200), pyrene, anthracene, tetracene, fluorene, spirofluorene, dendrimer, tetracene (e.g. rubrene derivatives), 1,10-phenanthroline derivatives (JP 2003-115387, JP 2004-311184 , JP 2001-267080, WO 02/043449), silacyclopentadiene derivatives (EP 1480280, EP 1478032, EP 1469533), borane derivatives, such as for example Si-containing triarylborane derivatives (US 2007/0087219 A1, formula ET -3), pyridine derivatives (JP 2004-200162), phenanthrolines, especially 1,10-phenanthroline derivatives, such as for example BCP and Bphen, as well as several phenanthrolines linked via biphenyl or other aromatic groups. (US 2007-0252517 A1) or phenanthroline linked to anthracene (US 2007-0122656 A1, see formulas ET-4 and ET-5).

Heterocyclic organic compounds, such as for example thiopyran dioxide, oxazole, triazole, imidazole or oxadiazole, are likewise suitable. N-containing 5-membered rings, such as for example oxazoles, preferably 1,3,4-oxadiazoles, for example compounds of the formulas ET-6, ET-7, ET-8 and ET-9 (in particular disclosed in US 2007/0273272 A1); Thiazoles, oxadiazoles, thiadiazoles, triazoles (see especially US 2008/0102311 A1 and Y.A. Levin, M.S. Skorobogatova, Khimiya Geterotsiklicheskikh Soedinenii 1967 (2), 339-341), preferably compounds of the formula ET-10 , Examples of use of silacyclopentadiene derivatives. Preferred compounds are of the formula (ET-6) to (ET-10):

Additionally, organic compounds such as derivatives of fluorenone, fluorenylidenemethane, perylenetetracarboxylic acid, anthraquinonedimethane, diphenoquinone, anthrone and anthraquinonediethylenediamine can be used.

2,9,10-substituted anthracene (with 1- or 2-naphthyl, and 4- or 3-biphenyl) or a molecule containing two anthracene units (see US 2008/0193796 A1, formula ET-11) is desirable. The connection of 9,10-substituted anthracene units to benzimidazole derivatives (see US 2006/147747 A and EP 1551206 A1, formulas ET-12 and ET-13) is also very advantageous.

Compounds capable of producing electron injection and/or electron transport properties preferably give rise to a LUMO below -2.5 eV (relative to the vacuum level), particularly preferably below -2.7 eV.

Formulations of the invention may also include an emitter. The term emitter refers to a material that enables a radiative transition to the ground state with emission of light after excitation, which can occur by any type of energy transfer. In general, two classes of emitters are known: fluorescent and phosphorescent emitters. The term fluorescent emitter refers to a material or compound in which a radiative transition from an excited singlet state to the ground state occurs. The term fluorescent emitter also includes emitters that exhibit delayed fluorescence, such as organic compounds that exhibit thermally activated delayed fluorescence. The term phosphorescent emitter denotes a luminescent material or compound, preferably containing a transition metal.

Emitters are also often called dopants when the dopant causes the properties described above in the system. In systems comprising a matrix material and a dopant, the dopant is believed to refer to the component having a smaller proportion in the mixture. Correspondingly, in systems comprising a matrix material and a dopant, the matrix material is taken to mean the component whose proportion is greater in the mixture. Accordingly, the term phosphorescent emitter may also be taken to mean, for example, a phosphorescent dopant.

Compounds capable of emitting light include, among others, fluorescent emitters and phosphorescent emitters. These are, in particular, stilbenes, stilbenamines, styrylamines, coumarins, rubrenes, rhodamines, thiazoles, thiadiazoles, cyanines, thiophenes, paraphenylenes, perylenes, phthalocyanines, porphyrins, ketones, quinolines and imines. , and compounds containing anthracene and/or pyrene structures. Compounds that are capable of emitting light with high efficiency from the triplet state even at room temperature, i.e. exhibiting electrophosphorescence instead of electrofluorescence, which often leads to an increase in energy efficiency, are particularly preferred. Suitable for this purpose are, firstly, compounds containing heavy atoms with an atomic number greater than 36. Compounds containing d- or f-transition metals that satisfy the conditions mentioned above are preferred. Here, corresponding compounds containing elements of groups 8 to 10 (Ru, Os, Rh, Ir, Pd, Pt) are particularly preferred. Suitable functional compounds here are various complexes as described for example in WO 02/068435 A1, WO 02/081488 A1, EP 1239526 A2 and WO 2004/026886 A2.

Preferred compounds that can act as fluorescent emitters are described by way of example below. Preferred fluorescent emitters are selected from the class of monostyrylamines, distyrylamines, tristyrylamines, tetrastyrylamines, styrylphosphine, styryl ethers and arylamines.

Monostyrylamine is taken to mean a compound containing one substituted or unsubstituted styryl group and at least one, preferably aromatic, amine. Distyrylamine is taken to mean a compound containing two substituted or unsubstituted styryl groups and at least one, preferably aromatic, amine. Tristyrylamine is taken to mean a compound containing three substituted or unsubstituted styryl groups and at least one, preferably aromatic, amine. Tetrastyrylamine is taken to mean a compound containing four substituted or unsubstituted styryl groups and at least one, preferably aromatic, amine. The styryl group is particularly preferably stilbene, which may also be further substituted. The corresponding phosphines and ethers are defined analogously to the amines. Arylamine or aromatic amine in the meaning of the present invention is taken to mean a compound containing a system of three substituted or unsubstituted aromatic or heteroaromatic rings directly bonded to nitrogen. At least one of these aromatic or heteroaromatic ring systems is preferably a fused ring system, preferably having at least 14 aromatic ring atoms. Preferred examples thereof are aromatic anthraceneamine, aromatic anthracenediamine, aromatic pyrenamine, aromatic pyrenediamine, aromatic chrysenamine or aromatic chrysendiamine. Aromatic anthraceneamine is taken to mean a compound in which one diarylamino group is bonded directly to an anthracene group, preferably at the 9-position. Aromatic anthracenediamine is taken to mean a compound in which two diarylamino groups are bonded directly to an anthracene group, preferably at the 2,6- or 9,10-position. Aromatic pyrenamines, pyrenediamines, chrysenamines and chrysenediamines are defined similarly, wherein the diarylamino group is bonded to the pyrene, preferably at the 1-position or 1,6-position.

Further preferred fluorescent emitters are indenofluorenamine or indenofluorenediamine, especially those described in WO 2006/122630; benzoindenofluoreneamine or benzoindenofluorenediamine, especially as described in WO 2008/006449; and in particular dibenzoindenofluoreneamine or dibenzoindenofluorenediamine described in WO 2007/140847.

Examples of compounds from the styrylamine class that can be used as fluorescent emitters include substituted or unsubstituted tristilbenamine, or WO 2006/000388, WO 2006/058737, WO 2006/000389, WO 2007/065549 and This is a dopant described in WO 2007/115610. Distyrylbenzene and distyrylbiphenyl derivatives are described in US 5121029. Additional styrylamines can be found in US 2007/0122656 A1.

Particularly preferred styrylamine compounds are the compounds of formula EM-1 described in US Pat. No. 7,250,532 B2 and the compounds of formula EM-2 described in DE 10 2005 058557 A1:

Particularly preferred triarylamine compounds are those described in CN 1583691 A, JP 08/053397 A and US 6251531 B1, EP 1957606 A1, US 2008/0113101 A1, US 2006/210830 A, WO 2008/006449 and DE 102008035413. Formula EM- disclosed in 3 to EM-15, and their derivatives:

Further preferred compounds that can be used as fluorescent emitters are naphthalene, anthracene, tetracene, benzanthracene, benzophenanthrene (DE 10 2009 005746), fluorene, fluoranthene, periplanthene, indenoperylene, phenanes. Trene, perylene (US 2007/0252517 A1), pyrene, chrysene, decacyclene, coronene, tetraphenylcyclopentadiene, pentaphenylcyclopentadiene, fluorene, spirofluorene, rubrene, coumarin (US 4769292 , US 6020078, US 2007/0252517 A1), pyran, oxazole, benzoxazole, benzothiazole, benzimidazole, pyrazine, cinnamic acid ester, diketopyrrolopyrrole, acridone and quinacridone (US 2007/ 0252517 A1).

Among the anthracene compounds, 9,10-substituted anthracene, such as for example 9,10-diphenylanthracene and 9,10-bis(phenylethynyl)anthracene, are particularly preferred. 1,4-bis(9'-ethynylanthracenyl)benzene is also a preferred dopant.

Rubrene, coumarin, rhodamine, quinacridone, such as for example DMQA (= N,N'-dimethylquinacridone), dicyanomethylenepyran, such as for example DCM (=4-(dicyanoethylene)- Equally preferred are derivatives of 6-(4-dimethylaminostyryl-2-methyl)-4H-pyran), thiopyran, polymethine, pyrylium and thiapyrylium salts, periplanthene and indenoperylene.

The blue fluorescent emitter is preferably a polyaromatic compound, such as for example 9,10-di(2-naphthylanthracene) and other anthracene derivatives, tetracene, xanthene, derivatives of perylene, such as for example 2 ,5,8,11- tetra- t-butylperylene, phenylene, e.g. 4,4'-bis(9-ethyl-3-carbazovinylene)-1,1'-biphenyl, fluorene , fluoranthene, arylpyrene (US 2006/0222886 A1), arylenevinylene (US 5121029, US 5130603), bis(azinyl)imine-boron compound (US 2007/0092753 A1), bis(azinyl)methene compounds and carbostyryl compounds.

A further preferred blue fluorescent emitter is C.H. Chen et al.: “Recent developments in organic electroluminescent materials”, Macromol. Symp. 125, (1997) 1-48 and “Recent progress of molecular organic electroluminescent materials and devices”, Mat. Sci. and Eng. R, 39 (2002), 143-222.

Further preferred blue fluorescent emitters are the hydrocarbons disclosed in DE 102008035413.

Preferred fluorescent emitters that exhibit delayed fluorescence are well known in the art and are described for example in C. Adachi et al., Nature, 492, 2012, 234-238, A. P. Monkman et al., Methods Appl. Fluoresc. 5 (2017) 012001 or E. Zysman-Colman et al., Adv. These are disclosed in Mater 2017, 29, 1605444.

Preferred compounds that can act as phosphorescent emitters are described below by way of example.

Examples of phosphorescent emitters are revealed by WO 00/70655, WO 01/41512, WO 02/02714, WO 02/15645, EP 1191613, EP 1191612, EP 1191614 and WO 2005/033244. In general, all phosphorescent complexes used according to the prior art for phosphorescent OLEDs and known to the person skilled in the art of organic electroluminescence are suitable, and the person skilled in the art will be able to use further phosphorescent complexes without inventive steps.

The phosphorescent metal complex preferably contains Ir, Ru, Pd, Pt, Os or Re, more preferably Ir.

Preferred ligands are 2-phenylpyridine derivatives, 7,8-benzoquinoline derivatives, 2-(2-thienyl)pyridine derivatives, 2-(1-naphthyl)pyridine derivatives, 1-phenylisoquinoline derivatives, 3-phenyl It is an isoquinoline derivative or 2-phenylquinoline derivative. All these compounds may be substituted with fluoro, cyano and/or trifluoromethyl substituents, for example for blue color. The auxiliary ligand is preferably acetylacetonate or picolinic acid.

In particular, complexes of Pt or Pd with tetradentate ligands of formula EM-16 are suitable.

Compounds of formula EM-16 are described in more detail in US 2007/0087219 A1, and for explanation of substituents and indices in the above formula, reference is made to this specification for disclosure purposes. Additionally, Pt-porphyrin complexes with expanded ring systems (US 2009/0061681 A1) and Ir complexes, such as 2,3,7,8,12,13,17,18-octaethyl-21H, 23H-porphyrin -Pt(II), tetraphenyl-Pt(II) tetrabenzoporphyrin (US 2009/0061681 A1), cis-bis(2-phenylpyridinato-N,C ² ')Pt(II), cis-bis (2-(2'-thienyl)pyridinato-N,C ³ ')Pt(II), cis-bis(2-(2'-thienyl)quinolinate-N,C ⁵ ') Pt(II), (2-(4,6-difluorophenyl)-pyridinato-N,C ² ')Pt(II) (acetylacetonate), or tris(2-phenylpyridinato) -N,C ² ')Ir(III) (= Ir(ppy) ₃ , green), bis(2-phenylpyridinato-N,C ² )Ir(III) (acetylacetonate) (= Ir( ppy) ₂ Acetylacetonate, green, US 2001/0053462 A1, Baldo, Thompson et al., Nature 403, (2000), 750-753), bis(1-phenylisoquinolinato-N,C ^2' )( 2-phenylpyridinato-N,C ^2' )iridium(III), bis(2-phenylpyridinato-N,C ^2' )(1-phenylisoquinolinato-N,C ^2' ) Iridium(III), bis(2-(2'-benzothienyl)pyridinato-N,C ^3' )iridium(III) (acetylacetonate), bis(2-(4',6'- Difluorophenyl)pyridinato-N,C ^2' )iridium(III) (picolinate) (FIrpic, blue), bis(2-(4',6'-difluorophenyl)pyridine To-N,C ^2' )Ir(III) (tetrakis(1-pyrazolyl)borate), tris(2-(biphenyl-3-yl)-4-tert-butylpyridine)iridium(III), ( ppz) ₂ Ir(5phdpym) (US 2009/0061681 A1), (45ooppz) ₂ Ir(5phdpym) (US 2009/0061681 A1), derivatives of the 2-phenylpyridine-Ir complex, such as, for example, PQIr (= Iridium(III) bis(2-phenylquinolyl-N,C ^2' )acetylacetonate), tris(2-phenylisoquinolinato-N,C)Ir(III) (red), bis(2- (2'-benzo[4,5-a]thienyl)pyridinato-N,C ³ )Ir (acetylacetonate) ([Btp ₂ Ir(acac)], red, Adachi et al . Appl. Phys. Lett . 78 (2001), 1622-1624).

Trivalent lanthanides, such as, for example, complexes of Tb ³⁺ and Eu ³⁺ (J. Kido et al., Appl. Phys. Lett. 65 (1994), 2124, Kido et al., Chem. Lett. 657, 1990, US 2007 /0252517 A1), or phosphorescent complex of Pt(II), Ir(I), Rh(I) with maleonitrile dithiolate (Johnson et al., JACS 105, 1983, 1795), Re(I) tricarbonyl -diimine complexes (especially Wrighton, JACS 96, 1974, 998), Os(II) complexes with cyano ligands, and bipyridyl or phenanthroline ligands (Ma et al., Synth. Metals 94, 1998, 245) This is equally suitable.

Additional phosphorescent emitters with tridentate ligands are described in US 6824895 and US 10/729238. Red emitting phosphorescent complexes are found in US 6835469 and US 6830828.

Particularly preferred compounds for use as phosphorescent dopants are in particular compounds of formula EM-17 (in particular US 2001/0053462 A1 and Inorg. Chem. 2001, 40(7), 1704-1711, JACS 2001, 123(18), 4304- 4312) and derivatives thereof.

Derivatives are described in US 7378162 B2, US 6835469 B2 and JP 2003/253145 A.

Furthermore, compounds of formula EM-18 to EM-21 (described in US 7238437 B2, US 2009/008607 A1 and EP 1348711) and their derivatives can be used as emitters.

Quantum dots can likewise be used as emitters; these materials are disclosed in detail in WO 2012/013272 A1.

Compounds used as host materials, especially with emitting compounds, include materials from various classes of materials.

The host material has a larger band gap between HOMO and LUMO than commonly used emitter materials. Additionally, preferred host materials exhibit properties of hole- or electron-transport materials. Furthermore, the host material can have both electron- and hole-transport properties.

The host material is also called a so-called matrix material in some cases, especially when the host material is used in combination with a phosphorescent emitter in an OLED.

Preferred host or co-host materials, especially used with fluorescent dopants, are oligoarylenes (e.g. 2,2',7,7'-tetraphenylspirobifluorene according to EP 676461) or dinaphthylanthracene), especially oligoarylenes containing condensed aromatic groups, such as for example anthracene, benzanthracene, benzophenanthrene (DE 10 2009 005746, WO 2009/069566), phenanthrene, tetracene, coronene, Chrysene, fluorene, spirofluorene, perylene, phthaloperylene, naphthaloperylene, decacyclene, rubrene, oligoarylenevinylene (e.g. DPVBi = 4,4'- according to EP 676461 Bis(2,2-diphenylethenyl)-1,1'-biphenyl or spiro-DPVBi), polypodal metal complexes (e.g. according to WO 04/081017), especially 8-hydroxyquinoline Metal complexes, for example AlQ ₃ (= aluminum(III) tris(8-hydroxyquinoline)) or bis(2-methyl-8-quinolinoleto)-4-(phenylphenolinoleto)aluminum, also Imidazole chelates (US 2007/0092753 A1) and quinoline-metal complexes, aminoquinoline-metal complexes, benzoquinoline-metal complexes, hole-conducting compounds (for example according to WO 2004/058911), electron-conducting compounds, especially ketones, Phosphine oxides, sulfoxides, etc. (e.g. according to WO 2005/084081 and WO 2005/084082), atropisomers (e.g. according to WO 2006/048268), boronic acid derivatives (e.g. according to WO 2006/048268) 2006/117052) or benzanthracenes (e.g. according to WO 2008/145239).

Particularly preferred compounds that can serve as host or co-host materials are selected from the class of oligoarylenes, including anthracene, benzanthracene and/or pyrene, or atropisomers of these compounds. Oligoarylene in the meaning of the present invention is intended to mean a compound in which at least three aryl or arylene groups are bonded to each other.

Preferred host materials are selected in particular from compounds of formula (H-1):

wherein Ar ⁴ , Ar ⁵ and Ar ⁶ are in each case, identically or differently, an aryl or heteroaryl group having 5 to 30 aromatic ring atoms, which may be optionally substituted, and p ranges from 1 to 5. represents the integer of; The sum of π electrons in Ar ⁴ , Ar ⁵ and Ar ⁶ is at least 30 for p = 1, at least 36 for p = 2, and at least 42 for p = 3.

In the compounds of formula (H-1), the group Ar ⁵ particularly preferably represents anthracene, and the groups Ar ⁴ and Ar ⁶ are bonded at the 9- and 10-positions, where these groups may be optionally substituted. Very particularly preferably, at least one of the groups Ar ⁴ and/or Ar ⁶ is 1- or 2-naphthyl, 2-, 3- or 9-phenanthrenyl, or 2-, 3-, 4-, 5- It is a condensed aryl group selected from , 6- or 7-benzanthracenyl. Anthracene-based compounds are described in US 2007/0092753 A1 and US 2007/0252517 A1, for example 2-(4-methylphenyl)-9,10-di-(2-naphthyl)anthracene, 9-(2- Naphthyl)-10-(1,1'-biphenyl)anthracene and 9,10-bis[4-(2,2-diphenylethenyl)phenyl]anthracene, 9,10-diphenylanthracene, 9,10 -bis(phenylethynyl)anthracene and 1,4-bis(9'-ethynylanthracenyl)benzene. Compounds containing two anthracene units (US 2008/0193796 A1), such as 10,10'-bis[1,1',4',1'']terphenyl-2-yl-9,9'- Bisanthracenyl is preferred.

Further preferred compounds are arylamines, styrylamines, fluorescein, diphenylbutadiene, tetraphenylbutadiene, cyclopentadiene, tetraphenylcyclopentadiene, pentaphenylcyclopentadiene, coumarin, oxadiazole, bisbenzoxa Derivatives of zoline, oxazole, pyridine, pyrazine, imine, benzothiazole, benzoxazole, benzimidazole (US 2007/0092753 A1), for example 2,2',2"-(1,3,5- phenylene)tris[1-phenyl-1H-benzimidazole], aldazine, stilbene, styrylarylene derivatives, such as 9,10-bis[4-(2,2-diphenylethenyl)phenyl ]Anthracene, and distyrylarylene derivatives (US 5121029), diphenylethylene, vinylanthracene, diaminocarbazole, pyran, thiopyran, diketopyrrolopyrrole, polymethine, cinnamic acid ester, and fluorescent dye.

Derivatives of arylamines and styrylamines, for example TNB (=4,4'-bis[N-(1-naphthyl)-N-(2-naphthyl)amino]biphenyl) are particularly preferred. Metal-oxinoid complexes such as LiQ or AlQ ₃ can be used as co-hosts.

Preferred compounds with oligoarylene as matrix are US 2003/0027016 A1, US 7326371 B2, US 2006/043858 A, WO 2007/114358, WO 2008/145239, JP 3148176 B2, EP 1009044, US 2004/0183 83, W.O. 2005/061656 A1, EP 0681019B1, WO 2004/013073A1, US 5077142, WO 2007/065678 and DE 102009005746, where particularly preferred compounds are represented by formulas H-2 to H-8.

Furthermore, compounds that can be used as hosts or matrices include materials used with phosphorescent emitters.

These compounds, which can also be used as structural elements in polymers, include CBP (N,N-biscarbazolylbiphenyl), carbazole derivatives (e.g. WO 2005/039246, US 2005/0069729, JP 2004/288381, according to EP 1205527 or WO 2008/086851), azacarbazole (e.g. according to EP 1617710, EP 1617711, EP 1731584 or JP 2005/347160), ketone (e.g. according to WO 2004/093207 or DE 10200803394 3) , phosphine oxides, sulfoxides and sulfones (e.g. according to WO 2005/003253), oligophenylenes, aromatic amines (e.g. according to US 2005/0069729), amphipathic matrix materials (e.g. according to WO 2007/137725 (according to DE 102008017591), silanes (e.g. according to WO 2005/111172), 9,9-diarylfluorene derivatives (e.g. according to DE 102008017591), azaboroles or boronic acid esters (e.g. according to WO 2006/117052) (according to WO 2007/063754), triazine derivatives (e.g. according to DE 102008036982), indolocarbazole derivatives (e.g. according to WO 2007/063754 or WO 2008/056746), indenocarbazole derivatives (e.g. according to DE 102009023155) and according to DE 102009031021), diazaphosphole derivatives (for example according to DE 102009022858), triazole derivatives, oxazole and oxazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives, pyrazolone derivatives, disti Rilpyrazine derivatives, thiopyran dioxide derivatives, phenylenediamine derivatives, tertiary aromatic amines, styrylamines, amino-substituted chalcone derivatives, indole, hydrazone derivatives, stilbene derivatives, silazane derivatives, aromatic dimethylidene compounds, Carbodiimide derivatives, metal complexes of 8-hydroxyquinoline derivatives, such as for example AlQ ₃ (which may also contain triarylaminophenol ligands) (US 2007/0134514 A1), metal complexes/polysilane compounds, and thiophene, benzothiophene and dibenzothiophene derivatives.

Examples of preferred carbazole derivatives are mCP (=1,3-N,N-dicarbazolylbenzene (=9,9'-(1,3-phenylene)bis-9H-carbazole)) (formula H- 9), CDBP (= 9,9'-(2,2'-dimethyl[1,1'-biphenyl]-4,4'-diyl)bis-9H-carbazole), 1,3-bis(N ,N'-dicarbazolyl)benzene (= 1,3-bis(carbazol-9-yl)benzene), PVK (polyvinylcarbazole), 3,5-di(9H-carbazol-9-yl) Biphenyl and CMTTP (Formula H-10). Particularly preferred compounds are disclosed in US 2007/0128467 A1 and US 2005/0249976 A1 (formulas H-11 and H-13).

Preferred tetraaryl-Si compounds are described, for example, in US 2004/0209115, US 2004/0209116, US 2007/0087219 A1 and H. Gilman, E.A. Zuech, Chemistry & Industry (London, United Kingdom), 1960, 120.

Particularly preferred tetraaryl-Si compounds are represented by formulas H-14 to H-21.

Particularly preferred compounds from group 4 for the preparation of matrices for phosphorescent dopants are disclosed in particular in DE 102009022858, DE 102009023155, EP 652273 B1, WO 2007/063754 and WO 2008/056746, where particularly preferred compounds have the formula H- 22 to H-25.

Regarding the functional compounds that can be used according to the invention and that can serve as host materials, materials containing at least one nitrogen atom are particularly preferred. These preferably include aromatic amines, triazine derivatives and carbazole derivatives. Therefore, carbazole derivatives show particularly surprisingly high efficiencies. Triazine derivatives yield electronic devices with unexpectedly long lifetimes.

It may also be desirable to use a plurality of different matrix materials as a mixture, in particular at least one electron-conducting matrix material and at least one hole-conducting matrix material. As described for example in WO 2010/108579, it is equally preferred to use mixtures of charge transport matrix materials and electrically inactive matrix materials which, if any, do not participate to a significant extent in charge transport.

Furthermore, compounds that improve the transition from the singlet state to the triplet state and are used as supports for functional compounds with emitter properties to improve the phosphorescence properties of such compounds can be used. For this purpose, carbazole and bridged carbazole dimer units (for example described in WO 2004/070772 A2 and WO 2004/113468 A1) are suitable. For this purpose, ketones, phosphine oxides, sulfoxides, sulfones, silane derivatives and similar compounds (for example described in WO 2005/040302 A1) are also suitable.

n-dopant herein is taken to mean a reducing agent, ie an electron donor. Preferred examples of n-dopants are W(hpp) ₄ and other electron-rich metal complexes (according to WO 2005/086251 A2), P=N compounds (e.g. WO 2012/175535 A1, WO 2012/175219 A1) , naphthylenecarbodiimide (e.g. WO 2012/168358 A1), fluorene (e.g. WO 2012/031735 A1), free radicals and diradicals (e.g. EP 1837926 A1, WO 2007/107306 A1), pyridines (e.g. EP 2452946 A1, EP 2463927 A1), N-heterocyclic compounds (e.g. WO 2009/000237 A1) and acridine, as well as phenazines (e.g. US 2007/145355 A1).

More preferred host materials are organic compounds with a small gap between the S ₁ and T ₁ energy levels. These compounds can be used as fluorescent emitters that exhibit delayed fluorescence as described above. However, these compounds can also be used as host compounds for fluorescent emitters, i.e. as pumps to populate the singlet energy level of the fluorescent emitter. Generally, this process is called hyperfluorescence. Suitable host compounds are those already mentioned above as suitable as delayed fluorescence emitters.

Furthermore, the formulation may include wide band gap materials as functional materials. Wide band gap materials are taken to mean materials within the meaning of the disclosure of US 7,294,849. These systems exhibit particularly advantageous performance data in electroluminescent devices.

Compounds used as wide band gap materials may have a band gap of 2.5 eV or more, preferably 3.0 eV or more, particularly preferably 3.5 eV or more. The band gap can be calculated using, in particular, the energy levels of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO).

Furthermore, the formulation may include hole blocking material (HBM) as a functional material. Hole blocking materials refer to materials that prevent or minimize the transfer of holes (positive charge) in a multilayer system, especially when these materials are arranged in the form of layers adjacent to an emitting layer or a hole conducting layer. Typically, hole blocking materials have lower HOMO levels than hole transporting materials in adjacent layers. A hole blocking layer is often placed between the light emitting layer and the electron transport layer in OLED.

Basically any known hole blocking material can be used. In addition to other hole blocking materials described elsewhere in this application, advantageous hole blocking materials include metal complexes (US 2003/0068528), such as for example bis(2-methyl-8-quinolinoleato)(4-phenylphenolate) It is aluminum(III) (BAlQ). For this purpose, Fac-tris(1-phenylpyrazolato-N,C2)iridium(III) (Ir(ppz) ₃ ) (US 2003/0175553 A1) is likewise used. Phenanthroline derivatives, such as for example BCP, or phthalimides, such as for example TMPP, can likewise be used.

Furthermore, advantageous hole blocking materials are described in WO 00/70655 A2, WO 01/41512 and WO 01/93642 A1.

Furthermore, the formulation may include electronic blocking material (EBM) as a functional material. Electron blocking materials refer to materials that prevent or minimize the transfer of electrons in a multilayer system, especially when such materials are disposed in the form of layers adjacent to an emitting layer or an electron conducting layer. Typically, electron blocking materials have higher LUMO levels than electron transport materials in adjacent layers.

Basically any known hole blocking material can be used. In addition to other electron blocking materials described elsewhere in this application, advantageous electron blocking materials are transition-metal complexes, such as Ir(ppz) ₃ (US 2003/0175553).

The electron blocking material may preferably be selected from amines, triarylamines and their derivatives.

Furthermore, the functional compounds that can be used as organic functional materials in the formulation preferably have a molecular weight of ≤ 3,000 g/mol, more preferably ≤ 2,000 g/mol and most preferably ≤ 1,000, if they are low molecular weight compounds. It is g/mol.

Additionally, functional compounds that are distinguished by a high glass transition temperature are of particular interest. In this regard, particularly preferred functional compounds which can be used as organic functional materials in formulations have a glass transition temperature, as determined according to DIN 51005, of ≧70°C, preferably ≧100°C, more preferably ≧125°C, And most preferably ≥ 150°C.

The formulation may also include polymers as organic functional materials. The compounds described above as organic functional materials, which often have relatively low molecular weights, can also be mixed with polymers. Likewise, these compounds can be incorporated into polymers by covalent bonds. This is possible, in particular, with compounds substituted by reactive leaving groups such as bromine, iodine, chlorine, boronic acid or boronic acid esters, or by reactive polymerizable groups such as olefins or oxetanes. They can be used as monomers for the preparation of corresponding oligomers, dendrimers or polymers. Here, oligomerization or polymerization preferably takes place via halogen functional groups or boronic acid functional groups, or via polymerizable groups. Polymers can also be crosslinked through these types of groups. The compounds and polymers according to the invention can be used as crosslinked or non-crosslinked layers.

Polymers that can be used as organic functional materials often contain units or structural elements described in the context of the compounds described above, especially those disclosed and extensively listed in WO 02/077060 A1, WO 2005/014689 A2 and WO 2011/076314 A1. Contains. These are incorporated herein by reference. Functional materials may come from, for example, the following classes:

Group 1: Structural elements capable of producing hole injection and/or hole transport properties;

Group 2: Structural elements capable of producing electron injection and/or electron transport properties;

Group 3: Structural elements combining the properties described in relation to Group 1 and Group 2;

Group 4: Structural elements with luminescent properties, especially phosphorescent groups;

Group 5: Structural elements that improve the transition from the so-called singlet state to the triplet state;

Group 6: Structural elements that influence the morphology or also the emission color of the resulting polymer;

Group 7: Structural elements typically used as backbone.

Since the structural elements here may also have various functions, an explicit designation need not be advantageous. For example, structural elements of group 1 may likewise serve as a backbone.

Polymers with hole transport or hole injection properties used as organic functional materials, containing structural elements of group 1, may preferably contain units corresponding to the hole transport or hole injection materials described above.

Further preferred structural elements of group 1 are, for example, triarylamines, benzidines, tetraaryl-para-phenylenediamines, carbazoles, azulenes, thiophenes, pyrroles and furan derivatives, and further O groups with high HOMO -, S- or N-containing heterocycle. These arylamines and heterocycles preferably have a HOMO greater than -5.8 eV (relative to the vacuum level), particularly preferably greater than -5.5 eV.

In particular, polymers with hole transport or hole injection properties are preferred, which contain at least one of the repeating units of the formula HTP-1:

In the formula, the symbols have the following meanings:

Ar ¹ is, in each case identically or differently to the different repeating unit, a single bond, or a monocyclic or polycyclic aryl group, which may be optionally substituted;

Ar ² is, identically or differently for the different repeating units in each case, a monocyclic or polycyclic aryl group, which may be optionally substituted;

Ar ³ is, identically or differently for the different repeating units in each case, a monocyclic or polycyclic aryl group, which may be optionally substituted;

m is 1, 2 or 3.

Particularly preferred are repeating units of the formula HTP-1 selected from the group consisting of units of the formula HTP-1A to HTP-1C:

In the formula, the symbols have the following meanings:

R ^a in each occurrence, identically or differently, is H, substituted or unsubstituted aromatic or heteroaromatic group, alkyl, cycloalkyl, alkoxy, aralkyl, aryloxy, arylthio, alkoxycarbonyl, silyl or carboxyl group, halogen an atom, cyano group, nitro group, or hydroxyl group;

r is 0, 1, 2, 3 or 4

s is 0, 1, 2, 3, 4 or 5.

In particular, polymers with hole transport or hole injection properties are preferred, which contain at least one of the repeating units of the formula HTP-2:

In the formula, the symbols have the following meanings:

T ¹ and T ² are independently selected from thiophene, selenophen, thieno[2,3-b]thiophene, thieno[3,2-b]thiophene, dithienothiophene, pyrrole and aniline; These groups may be substituted by one or more radicals R ^b ;

R ^b is independently in each case halogen, -CN, -NC, -NCO, -NCS, -OCN, -SCN, -C(=O)NR ⁰ R ⁰⁰ , -C(=O)X, -C (=O)R ⁰ , -NH ₂ , -NR ⁰ R ⁰⁰ , -SH, -SR ⁰ , -SO ₃ H, -SO ₂ R ⁰ , -OH, -NO ₂ , -CF ₃ , -SF ₅ , selected from optionally substituted silyl, carbyl or hydrocarbyl groups having 1 to 40 carbon atoms, which may be optionally substituted and may optionally contain one or more heteroatoms;

R ⁰ and R ⁰⁰ are each independently H, or an optionally substituted carbyl or hydrocarbyl group having 1 to 40 carbon atoms, which may be optionally substituted and may optionally contain one or more heteroatoms; ;

Ar ⁷ and Ar ⁸ , independently of each other, represent a monocyclic or polycyclic aryl or heteroaryl group, which may be optionally substituted, and is optionally substituted at the 2,3-position of one or both of the adjacent thiophene or selenophene groups. may be combined;

c and e are, independently of each other, 0, 1, 2, 3 or 4, where 1< c + e ≤ 6;

d and f are, independently of each other, 0, 1, 2, 3 or 4.

Preferred examples of polymers with hole transport or hole injection properties are described in particular in WO 2007/131582 A1 and WO 2008/009343 A1.

Polymers with electron injection and/or electron transport properties used as organic functional materials, containing structural elements from group 2, may preferably also contain units corresponding to the electron injection and/or electron transport materials described above. there is.

Further preferred structural elements of group 2, which have electron injection and/or electron transport properties, are for example pyridine, pyrimidine, pyridazine, pyrazine, oxadiazole, quinoline, quinoxaline and phenazine groups, as well as triaryl groups. derived from a borane group or an additional O-, S- or N-containing heterocycle with a low LUMO level. These structural elements of group 2 preferably have a LUMO (relative to the vacuum level) of less than -2.7 eV, especially preferably of less than -2.8 eV.

The organic functional material may preferably be a polymer containing structural elements from group 3, in which structural elements that improve hole and electron mobility (i.e. structural elements from groups 1 and 2) are directly connected to each other. Some of these structural elements may act here as emitters, where the emission color may be shifted, for example to green, red or yellow. Therefore, their use is advantageous for the generation of other emission colors or broadband emissions, for example by polymers that originally emit blue.

Polymers with luminescent properties used as organic functional materials, containing structural elements from group 4, may preferably also contain units corresponding to the emitter materials described above. Here, polymers containing phosphorescent groups are preferred, especially the emitting metal complexes described above containing corresponding units containing elements of groups 8 to 10 (Ru, Os, Rh, Ir, Pd, Pt).

Polymers used as organic functional materials, containing units of group 5 that improve the so-called transition from the singlet state to the triplet state, are preferably phosphorescent compounds, preferably containing structural elements of group 4 described above. It can be used as a polymer support. A polymeric triplet matrix may be used here.

For this purpose, carbazole and linked carbazole dimer units (for example described in DE 10304819 A1 and DE 10328627 A1) are particularly suitable. For this purpose, ketones, phosphine oxides, sulfoxides, sulfone and silane derivatives and similar compounds (for example described in DE 10349033 A1) are also suitable. Furthermore, preferred structural units can be derived from the compounds described above in relation to matrix materials used with phosphorescent compounds.

The further organic functional materials are preferably polymers containing units of group 6, which influence the morphology and/or the emission color of the polymer. These are those that, in addition to the polymers mentioned above, have at least one additional aromatic or another conjugated structure not taken into account among the groups mentioned above. Accordingly, these groups have little or no effect on charge-carrier mobility, non-organometallic complexes, or singlet-triplet transitions.

These types of structural units can influence the morphology and/or emission color of the resulting polymer. Therefore, depending on the structural units, these polymers can also be used as emitters.

Therefore, for fluorescent OLEDs, aromatic structural elements with 6 to 40 carbon atoms or also tolane, stilbene or bistyrylarylene derivative units are preferred, each of which may be substituted by one or more radicals. wherein 1,4-phenylene, 1,4-naphthylene, 1,4- or 9,10-anthrylene, 1,6-, 2,7- or 4,9-pyrenylene, 3,9- or 3,10-perylenylene, 4,4'-biphenylene, 4,4"-terphenylylene, 4,4'-bi-1,1'-naphthylylene, 4,4'-tolanylene. , It is particularly preferred to use groups derived from 4,4'-stilbenylene or 4,4"-bistyrylarylene derivatives.

Polymers used as organic functional materials preferably contain units of group 7, which contain aromatic structures with 6 to 40 carbon atoms, which are often used as backbone.

These include in particular 4,5-dihydropyrene derivatives, 4,5,9,10-tetrahydropyrene derivatives, fluorene derivatives (e.g. described in US 5962631, WO 2006/052457 A2 and WO 2006/118345A1) , 9,9-spirobifluorene derivatives (e.g. disclosed in WO 2003/020790 A1), 9,10-phenanthrene derivatives (e.g. disclosed in WO 2005/104264 A1), 9,10-di Hydrophenanthrene derivatives (e.g. disclosed in WO 2005/014689 A2), 5,7-dihydrodibenzoxephine derivatives, and cis- and trans-indenofluorene derivatives (e.g. disclosed in WO 2004/041901 A1 and described in WO 2004/113412 A2), and binapthylene derivatives (e.g. described in WO 2006/063852 A1), and further units (e.g. WO 2005/056633 A1, EP 1344788 A1, WO 2007/ 043495 A1, WO 2005/033174 A1, WO 2003/099901 A1 and DE 102006003710) are included.

Fluorene derivatives (e.g. disclosed in US 5,962,631, WO 2006/052457 A2 and WO 2006/118345 A1), spirobifluorene derivatives (e.g. disclosed in WO 2003/020790 A1), benzofluorene, di- The structural unit of group 7 is selected from benzofluorene, benzothiophene and dibenzofluorene groups, and their derivatives (e.g. disclosed in WO 2005/056633 A1, EP 1344788 A1 and WO 2007/043495 A1) Particularly desirable.

Particularly preferred structural elements of group 7 are represented by the general formula PB-1:

The symbols and exponents in the equations have the following meanings:

A, B and B' are each, also for different repeat units, identical or different, preferably -CR ^c R ^d -, -NR ^c -, -PR ^c -, -O-, -S-, - 2 selected from SO-, -SO ₂ -, -CO-, -CS-, -CSe-, -P(=O)R ^c -, -P(=S)R ^c - and -SiR ^c R ^d - is Ki;

R ^c and R ^d are in each case, independently, H, halogen, -CN, -NC, -NCO, -NCS, -OCN, -SCN, -C(=O)NR ⁰ R ⁰⁰ , -C(= _O ^{) ​ ​ ​} _{​ ​} ^​ _{​ 3} , -SF ₅ , is selected from optionally substituted silyl, carbyl or hydrocarbyl groups having 1 to 40 carbon atoms which may be optionally substituted and may optionally contain one or more heteroatoms, wherein The groups R ^c and R ^d may optionally form a spiro group with a fluorene radical to which they are attached;

X is halogen;

R ⁰ and R ⁰⁰ are each, independently, H, or an optionally substituted carbyl or hydrocarbyl group having 1 to 40 carbon atoms, which may be optionally substituted and optionally contain one or more heteroatoms. can;

g is, at each occurrence, independently 0 or 1, and h is at each occurrence independently 0 or 1, wherein the sum of g and h in the subunit is preferably 1;

m is an integer ≥ 1;

Ar ¹ and Ar ² independently represent a monocyclic or polycyclic aryl or heteroaryl group, which may be optionally substituted, and is optionally bonded to the 7,8-position or 8,9-position of the indenofluorene group. may be;

a and b are, independently of each other, 0 or 1.

When the groups R ^c and R ^d together with the fluorene group to which these groups are bonded form a spiro group, these groups preferably represent spirobifluorene.

Particularly preferred are repeating units of the formula PB-1 selected from the group consisting of units of the formula PB-1A to PB-1E:

In the formula, R ^c has the meaning described above for formula PB-1, r is 0, 1, 2, 3 or 4, and R ^e has the same meaning as the radical R ^c .

R ^e is preferably -F, -Cl, -Br, -I, -CN, -NO ₂ , -NCO, -NCS, -OCN, -SCN, -C(=O)NR ⁰ R ⁰⁰ , -C ^{( = O} ) a straight-chain, branched or cyclic alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy group having 1 to 20, preferably 1 to 12 carbon atoms, wherein one or more hydrogen The atoms may be optionally substituted with F or Cl and the groups R ⁰ , R ⁰⁰ and X have the meanings described above for formula PB-1.

Particularly preferred are repeating units of the formula PB-1 selected from the group consisting of units of the formula PB-1F to PB-1I:

In the formula, the symbols have the following meanings:

L is H, halogen, or an optionally fluorinated, linear or branched alkyl or alkoxy group having 1 to 12 carbon atoms, preferably H, F, methyl, i-propyl, t-butyl, n- represents pentoxy or trifluoromethyl; and

L' is an optionally fluorinated, linear or branched alkyl or alkoxy group having 1 to 12 carbon atoms and preferably represents n-octyl or n-octyloxy.

For carrying out the present invention, polymers containing more than one of the structural elements of groups 1 to 7 described above are preferred. Furthermore, it may be provided that the polymer preferably contains more than one of the structural elements from one of the groups described above, ie comprising a mixture of structural elements selected from one group.

In particular, in addition to at least one structural element with luminescent properties (group 4), preferably at least one phosphorescent group, it is additionally selected from groups 1 to 3, 5 or 6, preferably from groups 1 to 3, as described above. Particularly preferred are polymers containing at least one additional structural element.

When present in the polymer, the proportions of various classes of groups can be within a wide range known to those skilled in the art. The proportion of one class present in the polymer, in each case selected from the structural elements of groups 1 to 7 described above, is preferably ≥ 5 mol% in each case, particularly preferably ≥ 10 mol% in each case. If so, surprising benefits can be achieved.

The preparation of white-emitting copolymers is described in particular in detail in DE 10343606 A1.

To improve solubility, the polymer may contain corresponding groups. Preferably, it may be provided that the polymer contains substituents such that there are on average at least 2 non-aromatic carbon atoms per repeat unit, particularly preferably at least 4 and particularly preferably at least 8 non-aromatic carbon atoms. There is, and the average here refers to the number average. Here, individual carbon atoms can be replaced by O or S, for example. However, it is possible for a certain proportion, optionally all, of the repeating units to contain no substituents containing non-aromatic carbon atoms. Here, short-chain substituents are preferred, since long-chain substituents can have a negative effect on the layers that can be obtained using organic functional materials. The substituents preferably contain at most 12 carbon atoms, preferably at most 8 carbon atoms and particularly preferably at most 6 carbon atoms in the linear chain.

The polymers used according to the invention as organic functional materials may be random, alternating or regioregular copolymers, block copolymers or combinations of these copolymer forms.

In a further embodiment, the polymer used as organic functional material may be a non-conjugated polymer with side chains, where this embodiment is particularly important in phosphorescent OLEDs based on polymers. In general, phosphorescent polymers can be obtained by free-radical copolymerization of vinyl compounds, which vinyl compounds contain at least one unit with a phosphorescent emitter and/or at least one charge transport unit, as described in particular in US 7250226 It is disclosed in B2. Further phosphorescent polymers are described in particular in JP 2007/211243 A2, JP 2007/197574 A2, US 7250226 B2 and JP 2007/059939 A.

In a further preferred embodiment, the non-conjugated polymer contains backbone units connected to each other by spacer units. Examples of such triplet emitters based on non-conjugated polymers based on backbone units are disclosed, for example, in DE 102009023154.

In a further preferred embodiment, the non-conjugated polymer can be designed as a fluorescent emitter. Preferred fluorescent emitters based on non-conjugated polymers with side chains contain anthracene or benzanthracene groups in the side chains, or derivatives of these groups, these polymers being described, for example, in JP 2005/108556, JP 2005/285661 and It is disclosed in JP 2003/338375.

These polymers can often be used as electron- or hole-transport materials, where they are preferably designed as non-conjugated polymers.

Furthermore, the functional compounds used as organic functional materials in the formulation preferably have a molecular weight M _w of ≥ 10,000 g/mol, particularly preferably ≥ 20,000 g/mol and particularly preferably ≥ 50,000 g/ in the case of polymeric compounds. It is mol.

Here, the molecular weight M _w of the polymer preferably ranges from 10,000 to 2,000,000 g/mol, particularly preferably from 20,000 to 1,000,000 g/mol and very particularly preferably from 50,000 to 300,000 g/mol. The molecular weight M _w is determined using GPC (=gel permeation chromatography) against an internal polystyrene standard.

The documents cited above for description of functional compounds are incorporated by reference into this application for purposes of disclosure.

The formulation according to the invention may comprise all organic functional materials necessary for the production of the respective functional layers of the electronic device. If, for example, the hole transport, hole injection, electron transport or electron injection layer is built from exactly one functional compound, the formulation comprises exactly this compound as the organic functional material. If the release layer comprises an emitter, for example in combination with a matrix or host material, the formulation may be an organic functional material, precisely as described in more detail elsewhere in the present application, with the matrix or host material. Contains a mixture of sieves.

In addition to the above ingredients, the formulations according to the invention may also contain further additives and processing aids. These include, in particular, surface-active substances (surfactants), lubricants and greases, additives that modify viscosity, additives that increase conductivity, dispersants, hydrophobizers, adhesion promoters, flow improvers, anti-foaming agents, degassing agents, reactive or non-( Includes diluents, fillers, auxiliaries, processing aids, dyes, pigments, stabilizers, sensitizers, nanoparticles and inhibitors, which may be non-reactive. Accordingly, the formulation according to the invention may also comprise one or more additives ranging from 0.001 to 5% by volume, which lower the surface tension at a rate non-linear with respect to their content in the formulation.

The present invention further provides a method for preparing the formulation according to the present invention, wherein at least a first organic solvent, a 1,1-diphenylethylene derivative, and at least one organic functional material that can be used for the production of a functional layer of an electronic device are mixed. It's about how to become.

The formulations according to the invention can be used for the production of layered or multilayered structures, where organic functional materials are present in the layers, as required for the production of desirable electronic or optoelectronic components, such as OLEDs.

The formulations of the invention can preferably be used for the formation of a functional layer on a substrate or on one of the layers applied to the substrate. The substrate may or may not have a bank structure.

The invention likewise relates to a method for producing electronic devices, in which the formulation according to the invention is applied to a substrate and dried.

Functional layers include, for example, flood coating, dip coating, spray coating, spin coating, screen printing, relief printing, gravure printing, rotary printing, roller coating, flexographic printing, offset printing. or by nozzle printing, preferably inkjet printing, on the substrate or on one of the layers applied to the substrate.

After applying the formulation according to the invention to a substrate or to an already applied functional layer, a drying step can be carried out in order to remove the solvent from the continuous phase described above. Drying may preferably be carried out at relatively low temperatures and over a relatively long period of time to prevent bubble formation and obtain a uniform coating. Drying may be preferably carried out at a temperature ranging from 80 to 300°C, more preferably from 150 to 250°C and most preferably from 160 to 200°C. Drying here is preferably carried out at a pressure in the range of 10 ^-6 mbar to 2 bar, more preferably in the range of 10 ^-2 mbar to 1 bar, and most preferably in the range of 10 ^-1 mbar to 100 mbar. You can. During the drying process, the temperature of the substrate can vary from -15°C to 250°C. The duration of drying depends on the degree of drying to be achieved, where small amounts of water can be removed optionally, at relatively high temperatures, and preferably in combination with sintering.

Furthermore, it may be provided that the process is repeated several times, with the formation of different or identical functional layers. Here, crosslinking of the formed functional layer can occur, preventing its dissolution, as disclosed for example in EP 0 637 899 A1.

The invention also relates to an electronic device obtainable by a method for manufacturing an electronic device.

The invention further relates to an electronic device, which has at least one functional layer comprising at least one organic functional material, obtainable by the above-mentioned method for manufacturing electronic devices.

An electronic device is taken to mean a device comprising an anode, a cathode and at least one functional layer therebetween, where this functional layer comprises at least one organic or organometallic compound.

Organic electronic devices are preferably organic electroluminescent devices (OLED), polymeric electroluminescent devices (PLED), organic integrated circuits (O-IC), organic field-effect transistors (O-FET), organic thin-film transistors (O -TFT), organic light emitting transistor (O-LET), organic solar cell (O-SC), organic photovoltaic (OPV) cell, organic light detector, organic photoreceptor, organic field-quench device (O-FQD), organic It is an electrical sensor, a light-emitting electrochemical cell (LEC) or an organic laser diode (O-laser), more preferably an organic electroluminescent device (OLED) or a polymeric electroluminescent device (PLED).

The active ingredient is generally an organic or inorganic material introduced between the anode and the cathode, wherein such active ingredient influences, maintains and/or improves the properties of the electronic device, such as its performance and/or its lifetime. Sikkim), for example charge injection, charge transport or charge blocking materials, especially emission materials and matrix materials. Therefore, organic functional materials that can be used for the production of functional layers of electronic devices preferably include active ingredients of the electronic device.

Organic electroluminescent devices are preferred embodiments of the present invention. An organic electroluminescent device includes a cathode, an anode, and at least one emitting layer.

It is also preferred to use a mixture of two or more triplet emitters together with the matrix. The triplet emitter with a shorter wavelength emission spectrum here serves as a co-matrix for the triplet emitter with a longer wavelength emission spectrum.

In this case the proportion of matrix material in the emitting layer is preferably 50 to 99.9% by weight, more preferably 70 to 99.5% by weight and most preferably 85 to 99.5% by weight for the phosphorescent emitting layer. In this case, it is 75 to 97% by weight.

Accordingly, the proportion of the dopant is preferably 0.1 to 50% by weight, more preferably 0.5 to 30% by weight, and most preferably 0.5 to 15% by weight in the fluorescent emitting layer, and 3 to 25% by weight in the phosphorescent emitting layer. It is weight %.

The emitting layer of an organic electroluminescent device may also comprise a system comprising a plurality of matrix materials (mixed-matrix systems) and/or a plurality of dopants. In this case too, the dopant is generally the material with a smaller proportion in the system and the matrix material is the material with a larger proportion in the system. However, in individual cases, the proportion of individual matrix materials in the system may be smaller than the proportion of individual dopants.

The mixed-matrix system preferably comprises two or three different matrix materials, more preferably two different matrix materials. Here one of the two materials is preferably a material with hole-transport properties and the other material is a material with electron-transport properties. However, the desired electron transport and hole transport properties of the mixed-matrix components may also be combined primarily or entirely in a single mixed-matrix component, where the additional mixed-matrix component(s) fulfill different functions. The two different matrix materials are in a ratio of 1:50 to 1:1, preferably 1:20 to 1:1, more preferably 1:10 to 1:1 and most preferably 1:4 to 1:1. It may exist. Mixed matrix systems are preferably employed in phosphorescent organic electroluminescent devices. Further details on mixed-matrix systems can be found, for example, in WO 2010/108579.

In addition to these layers, the organic electroluminescent device may also comprise further layers, for example one or more hole injection layers, hole transport layers, hole blocking layers, electron transport layers, electron injection layers, exciton blocking layers, electron blocking layers, charge generation, in each case one or more Layer (IDMC 2003, Taiwan; Session 21 OLED (5), T. Matsumoto, T. Nakada, J. Endo, K. Mori, N. Kawamura, A. Yokoi, J. Kido, Multiphoton Organic EL Device Having Charge Generation Layer ) and/or organic or inorganic p/n conjugation. Here, one or more hole transport layers may be p-doped, for example with a metal oxide, such as MoO ₃ or WO ₃ , or a (per)fluorinated electron-deficient aromatic compound, and/or one or more electron transport layers may be n-doped. there is. Likewise, an intermediate layer that has an exciton blocking function and/or regulates charge balance, for example in an electroluminescent device, can be introduced between the two emitting layers. However, it should be pointed out that each of these layers does not necessarily need to be present. These layers may likewise be present upon use of the formulation according to the invention, as defined above.

In a further embodiment of the invention, the device comprises multiple layers. Here, the formulations according to the invention can preferably be used for the preparation of hole transport, hole injection, electron transport, electron injection and/or emission layers.

Accordingly, the invention also relates to an electronic device comprising at least three layers, but in a preferred embodiment all of the above layers from hole injection, hole transport, emission, electron transport, electron injection, charge blocking and/or charge generation layers, It relates here to an electronic device, wherein at least one layer is obtained by means of the formulation used according to the invention. The thickness of the layer, for example the hole transport and/or hole injection layer, may preferably range from 1 to 500 nm, more preferably from 2 to 200 nm.

Furthermore, the device may comprise layers built from further low molecular weight compounds or polymers that are not applied by the use of the formulation according to the invention. They can also be prepared by evaporation of low molecular weight compounds in high vacuum.

It may also be desirable to use the compounds not as pure substances, but instead as mixtures (blends) with additional polymeric, oligomeric, dendritic or low molecular weight substances of any desired type. These may, for example, improve electronic properties or they may emit themselves.

In a preferred embodiment of the invention, the formulation according to the invention comprises an organic functional material that is used as host material or matrix material in the release layer. The formulation herein may also comprise, in addition to the host material or matrix material, the emitter described above. The organic electroluminescent device here may include one or more emitting layers. If a plurality of emitting layers are present, they preferably have a plurality of emission maxima between 380 nm and 750 nm, i.e. various emitting compounds capable of causing fluorescence or phosphorescence are used in the emitting layers, so that an overall white emission is obtained. . Very particular preference is given to a three-layer system, the three layers of which exhibit blue, green and orange or red emission (for the basic structure, see for example WO 2005/011013). White emitting devices are suitable, for example, as backlighting of LCD displays or for general lighting applications.

Additionally, it is possible for multiple OLEDs to be arranged one above the other, which allows a further increase in efficiency with respect to light yield to be achieved.

To improve the coupling-out of light, in OLEDs the final organic layer on the light exit side can be in the form of, for example, nanofoam, which results in a reduction in the rate of total reflection. .

Furthermore, one or more layers are applied by a sublimation process, wherein the material is deposited in a vacuum sublimation apparatus at a pressure of less than 10 ^-5 mbar, preferably less than 10 ^-6 mbar, more preferably less than 10 ^-7 mbar. Organic electroluminescent devices applied by are preferred.

Furthermore, it is provided that one or more layers of the electronic device according to the invention are applied by an OVPD (organic vapor deposition) process or with the aid of carrier-gas sublimation, wherein the material is applied at a pressure of 10 ^-5 mbar to 1 bar. It could be.

Furthermore, one or more layers of the electronic device according to the invention can be printed from solution, such as, for example, by spin coating, or by any desired printing process, such as, for example, screen printing, flexographic printing or offset printing, but are particularly preferred. Alternatively, it may be provided to be manufactured by LITI (light-induced thermal imaging, thermal transfer printing) or inkjet printing.

A device usually includes a cathode and anode (electrodes). The electrodes (cathode, anode) are, for the purposes of the present invention, chosen such that their band energies correspond as closely as possible to the band energies of the adjacent organic layers in order to ensure highly efficient electron or hole injection.

The cathode is preferably a metal complex, a metal with a low work function, a metal alloy or a multilayer structure (e.g. an alkaline earth metal, an alkali metal, a main group metal or a lanthanoid (e.g. Ca, Ba, Mg, Al, In, Mg , Yb, Sm, etc.) and various metals such as). In the case of multilayer structures, in addition to the above metals, further metals with a relatively high work function can also be used, such as Ag and Ag nanowires (Ag NWs), and in this case combinations of metals, such as Ca, for example. /Ag or Ba/Ag are commonly used. It may also be desirable to introduce a thin intermediate layer of a material with a high dielectric constant between the metal cathode and the organic semiconductor. Alkali metal or alkaline earth metal fluorides, as well as the corresponding oxides (eg LiF, Li ₂ O, BaF ₂ , MgO, NaF, etc.) are suitable for this purpose. The layer thickness of this layer is preferably 0.1 to 10 nm, more preferably 0.2 to 8 nm, and most preferably 0.5 to 5 nm.

The anode preferably comprises materials with a high work function. The anode preferably has a potential greater than 4.5 eV relative to vacuum. On the other hand, for this purpose, metals with a high redox potential, for example Ag, Pt or Au, are suitable. On the other hand, metal/metal oxide electrodes (eg Al/Ni/NiO _x , Al/PtO _x ) may also be preferred. In some applications, at least one of the electrodes must be transparent to enable irradiation of organic materials (O-SC) or coupling out of light (OLED/PLED, O-laser). A preferred structure uses a transparent anode. Preferred anode materials herein are conductive, mixed metal oxides. ITO (indium tin oxide) or IZO (indium zinc oxide) are particularly preferred. Furthermore, conductively doped organic materials are preferred, especially conductively doped polymers, such as, for example, poly(ethylenedioxythiophene) (PEDOT) and polyaniline (PANI), or derivatives of these polymers. It is also preferred if a p-doped hole transport material is applied to the anode as a hole injection layer, where suitable p-dopants are metal oxides, for example MoO ₃ or WO ₃ , or (per)fluorinated electron-deficient aromatics. It is a compound. Additional suitable p-dopants are the compounds NDP9 or HAT-CN (hexacyanohexaazatriphenylene) from Novaled. This type of layer simplifies hole injection in materials with low HOMO, i.e. large values of HOMO.

In general, all materials used for layers according to the prior art can be used for further layers, and a person skilled in the art will be able to combine each of these materials with a material according to the invention in an electronic device without inventive steps.

Since the lifespan of such devices is dramatically shortened in the presence of water and/or air, the devices are correspondingly structured, provided with contacts and finally sealed, in a manner known per se, depending on the application.

The formulations according to the invention and the electronic devices obtainable therefrom, in particular organic electroluminescent devices, are distinguished over the prior art by one or more of the following surprising advantages:

1. Electronic devices obtainable using the formulation according to the invention show very high stability and a very long lifetime compared to electronic devices obtained using conventional methods.

2. The formulations according to the invention can be processed using conventional methods, whereby cost advantages can also be achieved.

3. The organic functional materials used in the formulation according to the present invention are not subject to any special restrictions, allowing the method of the present invention to be comprehensively used.

4. The coatings obtainable using the formulations of the invention show excellent quality, especially with regard to the uniformity of the coating.

5. The solvent is derived from sugars and is therefore based on a renewable resource. This makes these solvents an environmentally friendly and sustainable source for printed optoelectronic devices.

6. The formulation shows improved long-term stability with regard to precipitation of dissolved materials.

These advantages mentioned above are not accompanied by degradation of other electronic properties.

It should be pointed out that variations of the embodiments described herein fall within the scope of the present invention. Each feature disclosed in the present invention, unless explicitly excluded, may be replaced by an alternative feature that can be used for the same, equivalent, or similar purpose. Accordingly, each feature disclosed in the present invention, unless otherwise noted, should be regarded as an example of a generic series or as an equivalent or similar feature.

All features of the invention may be combined with one another in any way, as long as certain features and/or steps are not mutually exclusive. This applies in particular to the preferred features of the invention. Equally, features of non-essential combinations can be used separately (rather than in combination).

Additionally, it should be pointed out that many of the features of the invention, and particularly those of the preferred embodiments, are inventive in themselves and should not be considered merely as part of the embodiments of the invention. For these features, independent protection may now be sought as an alternative to or in addition to the respective claimed inventions.

The teachings regarding the technical operation disclosed in the present invention can be extracted and combined with other examples.

The invention is explained in more detail below with reference to working examples, but is not limited thereto.

Those skilled in the art will be able, using the detailed description, to manufacture further electronic devices according to the invention and, thus, to practice the invention within the full scope of the claims, without the need to avail themselves of inventive powers.

Work example

Determination of Solubility of Materials in Solvents

Determination of the solubility of a material in a solvent can be performed according to ISO norm 7579:2009, which describes solubility determination by photometric or gravimetric methods. Since the boiling points of the solvents considered are higher than 120°C, photometric techniques are used.

Solvents according to the invention exhibit improved solubility for active materials typically used in printed OLED devices.

dissolution test

The material(s) to be analyzed (used to form the functional layer) are weighed into a transparent glass flask. Next, the solvent (or preformed solvent mixture) was calculated to have a final concentration of 7 g/l and added to the solid mixture all at once. The mixture is stirred at room temperature (25°C) using a magnetic stirrer at 600 rpm until the mixture is completely dissolved as judged by visual inspection. At the end of the dissolution test, the mixture is further inspected under a light perpendicular to the line of sight to help identify undissolved particles. The “time of dissolution” t _DISS , sometimes also referred to as “dissolution time”, is measured using a chronometer and quantifies the time between the addition of solvent and the start of agitation until the final piece of material disappears into solution. The dissolution rate is determined by dividing 7 g/l by the time until complete dissolution is achieved (“dissolution time”).

The hole transport material (HTL) polymer described in WO 2016/107668 (polymer P1) is used. Solvents are classified according to dissolution time t _DISS at 25°C and dissolution type. The different dissolution types are summarized in Table 1.

Layer stability test experiment

Solvents according to the invention are tested for damage to preformed layers. The experiment is described in detail below.

1. Substrate preparation

The material "to be tested" is spin coated from solution onto a flat glass substrate measuring 30000 x 30000 x 1100 microns. The hole transport material (HTL) polymer (polymer P1) described in WO 2016/107668 is used. The solution contains 5 to 50 grams of material per liter of solvent. The formulation is prepared by weighing the solid material into the solvent. Dissolution of the formulation can be facilitated by stirring the mixture at room temperature using a magnetic stirrer for 1 to 6 hours. After complete dissolution, the formulation is transferred to a glovebox and filtered under inert conditions using a 0.2 micron PTFE filter. This formulation is used to spin coat a 50 nm thick layer onto a glass slide. Thickness is measured using an Alpha-step D-500 stylus type profile meter. The surface of the layer prepared using this preparation procedure is very flat and smooth. The average surface roughness (RMS) is below 1 nm. After deposition, the layer is annealed by placing the substrate on a hot plate for 30 min at a temperature of 220 °C.

2. Layer damage test conditions

To test the stability of the deposited material layer, solvent is charged into a solvent stable 10 pl disposable cartridge of a printer (Dimatix DMP-2831). Cartridge size determines droplet volume. In this case a 10 picoliter cartridge is used. The printer operates in a vibration-free environment and remains level. Printing conditions (see Dimatix user manual for detailed procedures) are controlled at a droplet speed of 4 meters per second. Printing is performed using only a single nozzle. Step 1) Place the substrate from the printer's substrate holder. The print pattern (Figure 1) is programmed to have a specific droplet volume. The droplets on the surface are composed of nine small single droplets placed very close together in a 3 x 3 matrix. After printing, the resulting droplets look like Figure 2 - every single droplet merges to form a single droplet of 90 picoliter droplet volume (different droplet volumes can be used, but need to be kept constant across a set of experiments). has exist). The image in FIG. 2 can be observed using a printer's fiducial camera. It looks down from the top of the substrate parallel to the jetting direction (see schematic diagram, Figure 3).

3. Layer Damage Test Procedure

Immediately after printing, a photo is taken using the printer's fiducial camera (Figure 2) and a timer is started. Several pictures are taken over a period of 5 minutes, the so-called “soaking time” (see Table 2). Because the field of view and x-/y-coordinates are linked, the diameter of the sessile drop is measured immediately after printing using a fiducial screen. This means you can export the x/y data for each marked location and thus calculate the distance between two points. This value is used as the droplet diameter and describes the interaction of the solvent on the surface. Photographs taken during the soaking time allow the interaction between the solvent and the surface, and the resulting surface modification, to be identified. The increasing dark shaded ring around the droplet border corresponds to surface damage by solvent. After a soaking time of 5 min, the substrate is placed in a vacuum drying chamber to remove the solvent and dry the layer completely. The pressure reaches 1·10 ^-4 mbar after pumping for 60 seconds. Allow the substrate to dry completely for at least 10 minutes. After drying, the substrate is removed and surface damage is quantified. Another photo is taken using the printer's fiducial camera to identify damage to the layer. To quantify damage to the layer, tactile measurements such as profilometry are performed (Figure 4). As a Key Performance Indicator (KPI) to qualify layer stability, the difference between the lowest and highest points across the profile measurements is used (see Figure 5). Values are in nanometers. After determining the KPI, the values are converted to a impairment indicator (DI), which can be seen in Figure 6. This can then be further used to identify layer stability for specific solvents.

To determine the layer damage rate, which is a measure of the rate of dissolution of the layer exposed to the second solvent, the KPI is divided by the soak time selected as 300 seconds. The units for coefficient of destruction are units of layer wear rate per hour, here nanometers per second [nm/sec]. In general, soak times should be within the range of typical solution processing steps. According to the DI, for a given combination of material and solvent in the layer, a coefficient of destruction of less than 0.066 nm/sec is acceptable to be used.

The solvent according to the invention causes little damage to the underlying layer.

Device example

The working examples presented below were made using devices with the following structures: Al cathode (100　nm)/ETL (40　nm)/HBL (10　nm)/EML (60　nm)/HTL (20　nm)/HIL (40　nm)/ITO anode (50　nm)/substrate), ETL, HBL, EML, HTL and HIL represent the electron transport layer, hole blocking layer, emission layer, hole transport layer and hole injection layer, respectively. The hole injection and hole transport layers of all examples are manufactured by an inkjet printing method to achieve the desired thickness. In the release layer a solvent blend according to the invention is used.

Description of manufacturing method

A glass substrate covered with pre-structured ITO and bank material (whereby banks are prefabricated on the substrate to form a pixelated device) is cleaned using ultrasonic treatment in isopropanol and then in deionized water. It was dried using an air-gun and subsequently annealed on a hotplate at 230°C for 2 hours.

A hole-injection layer (HIL) using PEDOT-PSS (Clevios Al4083, Heraeus) is inkjet printed on the substrate and dried under vacuum. The HIL is then annealed in air at 185° C. for 30 minutes.

On top of the HIL, a hole transport layer (HTL) is inkjet printed, dried in vacuum and annealed at 210° C. for 30 minutes in a nitrogen atmosphere. Polymer HTM-1 is used as material for the hole-transport layer. The structure of polymer HTM-1 is as follows:

The green emitting layer (G-EML) is also inkjet printed, vacuum dried and annealed at 160° C. for 10 minutes in a nitrogen atmosphere. The ink for the green emitting layer contains two host materials (i.e. HM-1 and HM-2) as well as one triplet emitter (EM-1). The materials are used in the following ratio: HM-1 : HM-2 : EM-1 = 40 : 40 : 20. The structure of these materials is as follows:

All inkjet printing methods are performed under yellow light and under ambient conditions.

The device is then moved to a deposition chamber, where deposition of the hole blocking layer (HBL), electron transport layer (ETL) and cathode (Al) is carried out using thermal evaporation. The device is then characterized in the glovebox.

As a hole blocking material for the hole blocking layer, ETM-1 is used. The material has the following structure:

In the electron transport layer (ETL), a 50:50 mixture of ETM-1 and LiQ is used. LiQ is lithium 8-hydroxyquinolinate.

To measure OLED performance in terms of current density-luminance-voltage performance, the device was driven by a sweeping voltage of -5V to 25V provided by a Keithley 2400 source measure unit. The voltage across the OLED device as well as the current through the OLED device were recorded by a Keithley 2400 SMU. The brightness of the device was detected with a calibrated photodiode. Measure photocurrent with a Keithley 6485/E picoammeter. For spectra, the brightness sensor is replaced with a fiberglass connection to an Ocean Optics USB2000+ spectrometer.

Device example 1

Inkjet printed OLED devices are fabricated with layers printed using an isosorbide containing formulation for the emissive layer. The structure of the pixelated OLED device is glass / ITO / HIL / HTM / EML / HBL / ETL / Al. The green emitting material dissolves at a concentration of 14 mg/ml.

Comparison device example 1

An inkjet printed OLED device is fabricated with a printed layer using 3-phenoxy-toluene as the solvent for the emissive layer. The structure of the pixelated OLED device is glass / ITO / HIL / HTM / EML / HBL / ETL / Al, whereby the banks were prefabricated on the substrate to form the pixelated device. The green emitting material dissolves at a concentration of 14 mg/ml.

The luminance efficiency, lifetime and voltage at a given luminance are significantly improved compared to the comparative example.

The resulting films of formulations according to the invention show improved film forming properties over the comparative examples as judged from the homogeneity of the EL emission from the printed subpixels.

Claims (23)

A formulation containing at least one quantum material and/or at least one organic functional material and isosorbide as a first solvent,
The at least one organic functional material is an organic conductor, an organic semiconductor, an organic fluorescent material, an organic delayed fluorescent material, an organic phosphorescent material, an organic light-absorbing material, an organic photosensitive material, an organic photosensitizing material, an organic p-dopant, an organic n-dopant. , transition metals, rare earths, organometallic complexes of lanthanides and actinides and other organic photoactive materials,
The content of the first solvent is in the range of 50 to 100% by volume based on the total amount of solvent in the formulation,
The formulation comprises, in addition to the first solvent, at least one second organic solvent ranging from 0 to 50% by volume based on the total amount of solvents in the formulation,
The formulation has a viscosity of 0.8 to 50 mPa ^. s range,
The formulation, wherein the organic functional material is a low molecular weight compound with a molecular weight of ≤ 3,000 g/mol. According to claim 1,
The formulation of claim 1, wherein the first solvent is a disubstituted isosorbide. According to claim 1,
The first solvent is a compound according to formula (I), a stereoisomer or a mixture of stereoisomers thereof,

In the formula
X is, on each occurrence, identically or differently, O or N, or both Xs are the same, or both
Y is, on each occurrence, identically or differently, S, NR ⁵ , O, or both Y are the same or both Y are O;
R ¹ and R ²
is the same or different in each case and is a linear, branched or cyclic aliphatic group having 1 to 40 aliphatic carbon atoms, or 1 to 20 aliphatic carbon atoms, wherein one CH ₂ group or more non-adjacent CH ₂ groups -O-, -S-, -NR ⁵ -, -CONR ⁵ -, -CO-O-, -C=O-, -R ⁵ C=CR ⁵ -, -C≡C-, -Si(R ⁵ ) ₂ , -Ge(R ⁵ ) ₂ -, -Sn(R ⁵ ) ₂ -, C=S, C=Se, C=NR ⁵ , P(=O)(R ⁵ ), -SO-, -SO ₂ - may be substituted by), an aryl or heteroaryl group having 1 to 60 aromatic carbon atoms, which groups may be substituted by one or more R ⁶ ;
R ³ and R ⁴
is the same or different in each case and is H, D, F, Cl, Br, 1 to 40 aliphatic carbon atoms, or a linear, branched or cyclic aliphatic group having 1 to 20 aliphatic carbon atoms (wherein one CH _Two or more non-adjacent CH ₂ groups are -O-, -S-, -NR ⁵ -, -CONR ⁵ -, -CO-O-, -C=O-, -R ⁵ C=CR ⁵ -, - C≡C-, -Si(R ⁵ ) ₂ , -Ge(R ⁵ ) ₂ -, -Sn(R ⁵ ) ₂ -, C=S, C=Se, C=NR ⁵ , P(=O)( R ⁵ ), -SO-, -SO ₂ -), an aryl or heteroaryl group having 1 to 60 aromatic carbon atoms, which groups may be substituted by one or more R ⁶ ;
R ⁵
is the same or different in each case and is H, a straight-chain alkyl or alkoxy group having 1 to 20 carbon atoms or a branched or cyclic alkyl or alkoxy group having 3 to 20 carbon atoms (and wherein one or more hydrogen atoms is D , F, Cl, Br, I, CN or NO ₂ ), or an aromatic or heteroaromatic ring system having 2 to 60 carbon atoms in the ring system, and R ⁵ is substituted by one or more R ⁶ may be;
R ⁶
is the same or different in each case and is H, a straight-chain alkyl or alkoxy group having 1 to 20 carbon atoms or a branched or cyclic alkyl or alkoxy group having 3 to 20 carbon atoms (and wherein one or more hydrogen atoms is D , F, Cl, Br, I, CN or NO ₂ ), or an aromatic or heteroaromatic ring system having 2 to 60 carbon atoms in the ring system. According to claim 3,
In formula (I) R ¹ and R ² are the same. According to claim 3,
R ³ and R ⁴ are the same, or both R ³ and R ⁴ are H. According to claim 3,
R ¹ and R ² are the same or different at each occurrence and are linear, branched or cyclic aliphatic groups having 1 to 40 aliphatic carbon atoms, R ¹ and R ² may be substituted with one or more R ⁶ , and R ⁶ has the meaning as defined in paragraph 3. According to claim 1,
The formulation of claim 1, wherein the first solvent has a surface tension of ≧20 mN/m. delete delete delete According to claim 1,
The formulation of claim 1, wherein the second organic solvent has a boiling point in the range of 100 to 400° C. According to claim 1,
The formulation, wherein the first solvent has a boiling point of 400°C or lower, or 350°C or lower. According to claim 1,
The formulation of claim 1, wherein the at least one organic functional material has a solubility in the first solvent and in the second organic solvent in the range of 1 to 250 g/l. According to claim 1,
The formulation comprising at least one additive in the range of 0.001 to 5% by volume relative to the total volume of the formulation. According to claim 1,
The formulation has a surface tension in the range of 10 to 70 mN/m. delete According to claim 1,
A formulation, wherein the content of the at least one organic functional material in the formulation ranges from 0.001 to 20% by weight based on the total weight of the formulation. According to claim 1,
The formulation of claim 1, wherein the at least one organic functional material is an organic semiconductor selected from the group consisting of hole injection materials, hole transport materials, emissive materials, electron transport materials, and electron injection materials. According to claim 1,
The formulation of claim 1, wherein the at least one organic semiconductor is selected from the group consisting of hole injection materials, hole transport materials, and hole emission materials. delete A method for producing the formulation according to any one of claims 1 to 7, 11 to 15, and 17 to 19, comprising:
A method of producing a formulation, wherein the at least one organic functional material and at least the first solvent are mixed. A method of manufacturing an electroluminescent device, comprising:
wherein the formulation according to any one of claims 1 to 7, 11 to 15, and 17 to 19 is deposited or printed on a surface and then dried, wherein the electroluminescence A method of manufacturing an electroluminescent device, wherein at least one layer of the device is manufactured. At least forming the formulation according to any one of claims 1 to 7, 11 to 15, and 17 to 19 into a film on a surface or forming a film by printing and then drying. An electroluminescent device in which one layer is manufactured.