TWI287532B - The use of an organic matrix material for producing an organic semiconductor material, and also to an organic semiconductor material comprising an organic matrix material and an organic dopant, and also to an electronic component - Google Patents

Abstract

The present invention relates to use of an organic matrix material for producing an organic semiconductor material, characterized in that the organic matrix material is comprised at least partly of a spirobifluorene compound, and the glass transition temperature of the organic matrix material is at least 120 DEG C and the highest occupied molecular orbital (HOMO) of the matrix material is at a maximum energy level of 5.4 eV; and also to an organic semiconductor material and electronic component.

Description

129. The invention relates to the manufacture of organic semiconductor materials using organic matrix materials, and also to organic semiconductor materials comprising organic matrix materials and organic dopants, and also to electronic components. Pre-monthly technology • Doping is known to alter the electronic properties of organic semiconductors, especially *· their electrical conductivity, as is the case with inorganic semiconductors such as germanium semiconductors. In this case, the generation of the charge carrier in the matrix material increases the initially relatively low electrical conductivity, and the change in the semiconductor Fermi level is achieved depending on the form of the dopant used, and the doping causes an increase in the conductivity of the charge transport layer. This reduces the loss of electrical limits and creates improved charge carrier transport between the contact points and the organic layer. For the doping of such an organic semiconductor, a strong electron acceptor such as tetracyanoquinodimethane (TCNQ) or 2,3,5,6·tetrafluorotetracyanobenzoquinone-monomethylpyrene (F4-TCNQ) is Known; reference to M. Pfeiffer, A. Beyer, T. Fritz, Κ Leo, Applied Physics Letters, 73 (22) 3202-3204 (1998) and J. Blochwitz, M. Pfeiffer, T. Fritz, K. Leo , Applied Physics Letters, 73 (6) 729-732 (1998). As a result of electron transfer methods for electron-like donor substrate materials (hole transport materials), these produce known holes whose number and mobility significantly alter the conductivity of the matrix material. 8 7 1287532 It is known that the matrix material is a biological compound such as 4,4',4,,-di(diphenylamine)triphenylamine (TDATA) '4,4',4"-parade (3-nonylphenylaniline) Triphenylamine (m-MTDATA) and N,N,N',N'-tetrakis(4_foxyphenyl)benzidine (MeO-TPD) The chemical structure of the above known matrix materials is as follows:

However, these compounds are thermally unstable, i.e. they have a low glass deficient > JDL degree and tend to crystallize at low '/Μ», which ultimately leads to unstable electronic components. The glass transition temperature is considered to be in the case of rapid auto-melting of the material, and the molecular movement is no longer possible due to the dynamic reasons, and the thermal parameters such as heat capacity or expansion coefficient suddenly change from the typical liquid value to the typical solid value. The temperature. The thermal stability of the matrix material when used with such a matrix material is particularly important, especially for morphological reasons, to prevent the formation of roughness on the conventional layer structure of such semiconductor materials at high operating temperatures. Moreover, thermal stability is important to limit the diffusion of dopants within the matrix material. The prior art also discloses thermally stable matrix materials such as 2, 2, 7, 7, and 4 8 Ί 287 532 " ) • (N,N-diphenylamine)-9,9'-spirobifluorene (spiro-TAD), However, because of their energy-rich positions in the highest occupied molecular domains (HOMOs), they cannot be doped.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an organic half-body material that is made of an organic matrix material. The matrix material is thermally stable and can be doped to provide a hole transport layer having the same hole conductivity for use in The organic semiconductor group and 'should be possible to apply the organic matrix by vapor deposition to provide a layer having a corresponding two-hole conductivity with a strong organic electron acceptor under reduced pressure by evaporation. The object is by an organic matrix material comprising at least a portion of a spirobiguanide compound of formula (1) Ί287532

(I; R-spiro-TAD } wherein R is at least one substituent on the phenyl radical, but not all R are simultaneously hydrogen. And/or formula (II)

Wherein R is a substituent other than hydrogen and R' is a substituent; the glass transition temperature of the organic matrix material is at least 120 ° C and the highest occupied molecular domain (HOMOs) of the matrix material is at a maximum energy level of 5.4 eV. Level. In the formula (I), the phenyl radical can thus be provided as having one or more substituents. • Preferably each of R and/or R' in formulas (I) and (II) is independently fluorenyl, fluorenyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, The group consisting of the third butyl group, NH2, N(CH4)2 and NPh2 is selected, and not all of the R of the formula (I) are simultaneously ruthenium. Particularly good for this snail double 8 compound by

11 Ί 287532 selected group. Similarly, the glass transition temperature of the spirobiguanide compound is between 120 ° C and 250 ° C, and the highest occupied molecular domain of the compound is between 4.5 electron volts and 5.4 electron volts. The level, preferably between 4.8 eV and 5.2, can also be achieved by an organic semiconductor material comprising an organic matrix material and an organic dopant, the organic matrix material comprising at least a portion of the matrix material used in accordance with the present invention. More people. Also preferably, the dopant is 2,3,5,6-σtetrafluoro[7,7,8,8,-tetracyanoquinodioxane or a derivative thereof. However, other dopants having similar acceptor functions and equal or greater molecular weights are possible; reference is made to 'German Patent 10357044.6. It is particularly preferred that the molar doping ratio of the dopant to the matrix material is between 1:1 and 1:1 〇. The phantom may be further achieved by an electronic component in which an organic matrix material is used which comprises at least a portion of the intuition as a spirobiguanide compound according to the matrix material of the present invention. .φ Finally, electronic components in the form of organic light-emitting diodes (OLEDs), photovoltaic cells, organic solar cells, organic diodes or organic field-effect transistors are available. The present invention is based on the use of an organic matrix material for the production of organic semiconductor materials to provide a thermally stable and doped hole transport layer for the surprising discovery of organic semiconductor components. Use of Matrix Materials The hole transfer materials applied by vapor deposition are provided such that they are co-evaporated with a strong organic electron acceptor under reduced pressure to produce a layer having a high electrical conductivity of 12 1287532. When the described organic matrix material is used, a stable, individual positively charged cation state of the hole transport material is achieved. Implementation

EXAMPLES Preparation of A·2,2,,7,7,-four (N,Nc_p-nonylaniline)-9,9'-spirobisindole (spiro-TTB)

2,2,,7,7,-tetrabromo-9,9,_spirobifluorene (1 gram, 15.8 millimoles), di-p-toluidine (14.2 grams, 72.1 millimoles) and third Sodium butoxide (9.6 g, 100 mmol) was stirred in loo ml of anhydrous toluene under nitrogen pressure at 60 ° C for 1 hour. Next, add tri-tert-butylphosphine (2 gram, 1 〇 millimolar, 6.3% based on tetrabromospirobiguanide) and 1 bar of ethanol (11) (92 mg, 0.4 mmol, 2.6%) The reaction mixture was heated and refluxed under nitrogen pressure based on tetrabromospiroindole. The progress of the reaction was monitored by thin layer chromatography (solvent: 50% hexane in dichloromethane). After 2·5 hours, no reactants were detected in TLC. The reaction mixture was cooled, blended with a solution of 100 mg of KCN in 20 ml of water and stirred for another hour at 60 〇c 13 Ί 287 532. After cooling to room temperature, the phases are separated, the organic phase is dried over sodium sulfate and the solution is removed. The crude product is recrystallized from dioxane twice and then re-precipitated from hexanes Dry down. Yield: slightly light green powder of 15·0 g (13·8 mmol, 87% theory). 1 NMR (500 MHz, CDC13 + hydrazine hydrate): 7.40 (d, 1 Η, J = 7.8), 7.00 (d, 4H, J = 8.3), 6.88 (d, 4H, J = 8.3), 6.85 (dd, 1H, J = 8.3, J = 2.0), 6.67 (d, 1H, J = 2.0), 2.30 (s, 6H). 13C NMR (127.5 MHz, CDC13 + hydrazine hydrate): 149.8, 146.7, 145.3, 136·1, 131·5, 129·5, 124.0, 123.2, 119.9, 119.3, 65.3, 20·6 〇Β. 2,2', Preparation of 7,7'-four (Ν,Ν_di-p-isopropylaniline)_9,9,·spirobiguanide (spiro_iPr-TAD) 4_isopropyl benzene

4. Isopropylaniline (49. 5 grams, 366 millimoles) was suspended in 200 ml of distilled water and gradually mixed with 200 ml of semi-concentrated sulfuric acid in an ice bath. Then a solution of sodium nitrite (25. 5 grams, 370 millimoles) in 2 milliliters of distilled water was added dropwise at a rate such that the temperature did not rise above 2oC. After the dropwise addition was completed, the mixture was at 2 Torr. In addition, 14 1287532 was stirred for 20 minutes. The resulting clear reddish diazonium salt solution was now added via a filter to a solution of potassium (3.55 grams, 813 millimoles) in 200 milliliters of distilled water. The reaction mixture was stirred at 80 ° C for 1 hour, during which time the solution turned black and vigorous gas evolution and oily organic phase separated. After cooling, the organic phase and the aqueous phase were removed and extracted four times or more with 1 mL of diethyl ether. The combined organic phases were washed with dilute sodium hydroxide solution and distilled water and dried over sodium sulfate. After the solvent was removed, the crude product was vacuum distilled in a membrane type. The slightly light red standard products are distilled at a temperature of 100-105 ° C (15 mbar). Yield: 75.3 grams (310 millimoles, 83% theory) of slightly light red liquid. 1H NMR (500 MHz, CDC13): 7.60 (d, 2H, J = 8.3), 6.98 (d, 2H, J = 8.3), 2.85 (q, 1H, J = 6.8), 1.22 (d, 6H, J = 6.8) o 13C NMR (127.5 MHz, CDC13): 148·4, 137·3, 128.6, 90·6, 33·7, 23·8. n-Ethyl-4-isopropylaniline

Acetic anhydride (26·0 g, 254 mmol) was slowly added dropwise to a solution of 4-isopropylaniline (17.2 g, 127 mmol) in 80 ml of chloroform. During this progress, intense heating of the reaction mixture takes place. 1287532 After the dropwise addition was completed, the mixture was stirred at room temperature for additional 2 hours. The reaction mixture was concentrated to dryness and the obtained pale red- white solid was evaporated and evaporated. Yield: 21.1 g (120 mmol, 94% theory) of a white solid. 1H NMR (500 MHz, CDC13): 7.88 (s, 1H), 7.40 (d, 2H, J = 8.3), 7.14 (d, 2H, J = 8.3), 2.86 (q, 1H, J = 6.8), L21 (d, 6H, J = 6.8). 13C NMR (127.5 MHz, CDC13): 168.6, 144.9, 135·6, 126.7, 120.2, 33·5, 24·3, 23.9. Melting point: 107 〇C (Document (Dyall, Australian Chemical Journal 17, 1964, 419): 104_105 oC) 〇 n-acetic acid-N,N-bis(4-isopropylphenyl)amine

4-isopropyl iodobenzene (29.2 g, 118 mmol), n-ethinyl-4-isopropylaniline (21·0 g, 118 mmol), copper powder (15.0 g, 237 mmol) Ear), potassium carbonate (65.4 grams, 474 millimoles) and 18-crown-6 (2.9 grams, 12 millimoles) were heated to reflux in 200 milliliters of 1,2-dichlorobenzene. The reaction was monitored by thin layer chromatography (solvent: 1% THF in dichloromethane). After 48 hours, the hot reaction mixture was filtered and the filter residue and solvent were thoroughly purged and removed on a rotary evaporator. The crude product was analyzed by 1287532 using 10% THF in m-gel. The product was concentrated to dryness, then recrystallized and dried under reduced pressure. Yield 14.31 g (48 mmol, 41% theory) slightly light brown solid. 1H NMR (500 MHz, CDC13): 7.21 (m, 8H), 2.90 (s (br.), 2H), 2.04 (s, 3H), 1.23 (s (br), 12H). N,N-bis(4-isopropylphenyl)amine

n-Ethyl-N,N-bis(4-isopropylphenyl)amine (5.4 g, 18.4 mmol) was heated to reflux in 100 ml of 20% aqueous ethanol. After the reaction was monitored by thin layer chromatography, no reaction was detected by TLC after 30 hours. The ethanol solution was poured into distilled water, and the pale brown precipitate was filtered off with suction, dissolved in dioxane and dried over sodium sulfate, concentrated solution and burned with 50% dichloromethane in a sinter. . The product was partially concentrated to dryness and the product was dried under reduced pressure. Yield: 4·0 g (16 mmol, 86% theory) of light brown solid 1 NMR (500 MHz, CDC13): 7.12 (d, 4 Η, J = 8.3), 6.99 (d, 4H, J = 8.3 ), 5.55 (s(br·), 1H), 2.86 (q, 2H, J = 6.8), 1.24 (d, 12H, J = 6.8). 13C NMR (127.5 MHz, CDC13): 141.3, 127.1, 117.7, 33.4, 24.1. 17 1287532

2,2',7,7'-tetra(N,N-di-p-isopropylaniline)_9,9,-spirobiguanide (spiro-iPr-TAD)

2,2,,7,7'_tetrabromo-9,9,_spirobifluorene (ι·7 g, 2.6 mmol), hydrazine, hydrazine-di-4-isopropylphenylamine ( 3·〇克, 12.0 mmol, and sodium butoxide (1.6 g, 17 mmol) in 1 ml of anhydrous toluene were stirred at 60 ° C for 1 hour under nitrogen pressure. Next, add tri-tert-butylphosphine (4.8 mg, 0.24 mmol, 9.2% based on tetrabromospirobiguanide) and palladium acetate (11) (27 mg, 0.12 mmol, 4.6% based on tetrabromospirobiguanide). And heating the reaction mixture under nitrogen pressure and refluxing. The reaction was monitored by thin layer chromatography (solvent: 20% dichloromethane in hexane). After 3 hours, no reactants were detected in TLC. The reaction mixture was cooled, blended with a solution of 100 mg of KCN in 20 ml of water, and stirred at 60 ° C for an additional hour. After cooling to room temperature, the phases were separated, and the organic phase was dried over sodium sulfate and the solution was removed. The crude product was recrystallized from hexanes and then dried under reduced pressure. Yield · · 2.8 g (2.1 mmol, 81% theory) of slightly yellowish, slightly crystalline powder. 1H NMR (500 MHz, CDC13): 7.41 (d, 1H,: Γ=8·3), 1287532 7.05 (d, 4H, J=8.3), 6·90 (ιη, 5H), 6.72 (s ), 1H), 2.85 (q, 2H, J = 6.8), 1.24 (d, 12H, J = 6.8). 13C NMR (127.5 MHz, CDC13): 150.7, 147.5, 146.3, 143.3, 137.2, 127.6, 125.3, 123.8, 120·8, 120.7, 66·2, 34·1, 24·8.

Tg: 144oC, Tk: 166 oC, Tm: 363 oC. The two organic substances, spiro-TTB and spiro-iPr-TAD, were each doped with F4-TCNQ and tested for electrical conductivity measurements. For these measurements, the doped layers were applied to two approximately 5 mm-wide contact points (made of indium tin oxide, ITO) by co-evaporation under reduced pressure, and the contact points were applied at distances of 1 mm from each other. On glass substrates. The contact point is externally connected to a current-voltage measuring instrument that allows the lateral current to be measured at a fixed applied voltage, whereby the lateral current, the electrical conductivity of the layer is then calculated from a simple resistance relationship, the electrical conductivity being The following equations are assisted by the decision: Conductivity = (lateral current * distance) / (width * layer thickness) Figures 1 and 2 each show the increase in lateral current of the two doped matrix materials as a function of layer thickness, The 50 nm thick spiro-TTB layer doped with 2.5% F4_TCNQ has an electrical conductivity of about 1.6E-5S/cm, and the 50 nm thick spiro-iPr_TAD layer doped with 5% F4-TCNQ The conductivity is about 8E-7S/cm. A specific embodiment of the electronic component of the invention in the form of an OLED having an organic matrix material, as used in accordance with the present invention, can be fabricated and contained in the case of a general design that is emitted via a substrate 19 -1287532 draels per ampere The current efficiency produced by the 45 cd/ampere light is also very high and fixed. Because of this stable hole transport layer, the OLED can operate stably at relatively high temperatures (up to 100 〇C) without causing a decrease in photo-electric properties. The invention as set forth in the above description, the scope of the invention, and the features of the invention may be embodied in various specific embodiments in various embodiments. 1287532 BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 shows the dependence of the lateral current on the layer thickness of the transfer layer of the organic matrix material ΤΤΒ_ΤΤΒ (F4-TCNQ doped); Figure 2 shows the lateral current in the organic matrix material snail - The dependence of the layer thickness of the transfer layer of iPr-TAD (doped with F4-TCNQ); Figure 3 shows the doped transfer layer and spiro-TTB (doped with F4-TCNQ) as a P-dopant Luminance signal voltage and power efficiency voltage characteristics of the organic light-emitting diode. Component Symbol Description None 22

Claims (1)

-1287532 X. Patent Application Range: 1. Use of an organic matrix material for producing an organic semiconductor material, characterized in that the organic matrix material comprises at least a part of a spirobiguanide compound of the formula (I) (I; R-spiro-TAD) wherein R is at least one substituent on a phenyl radical, but not all R are simultaneously hydrogen, and/or formula (II) (§) Wherein R is a substituent other than hydrogen and R' is a substituent, 23 1287532 The organic matrix material has a glass transition temperature of at least 120 ° C and the highest occupied molecular domain (HOMO) of the matrix material is at 5.4 eV. The maximum energy level. 2. The use of an organic matrix material according to claim 1 of the patent application, characterized in that each of R and/or R' of formula (I) and formula (II) is independently hydrogen, mercapto, or a group consisting of propyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, NH2, N(CH4)2, and NPh2, wherein not all of R of formula (I) is simultaneously hydrogen. 3. The use of an organic matrix material according to claim 2, characterized in that the spirobiguanide compound is (snail _iPr-TAD); and 24 4287532 The group consisting of (spiro-iPr2N-TAD) is selected. The use of the organic matrix material according to any one of claims 1 to 3, characterized in that the glass transition temperature of the spirobiguanide compound is between 120 ° C and 250 ° C, And the highest occupied molecular domain of the character is between the energy level of between 4. 5 electron volts and 5.4 electron volts, preferably between 4·8 electron volts and $ electron volts. An organic semiconductor material comprising an organic matrix material and an organic dopant is characterized in that the organic matrix material comprises, at least in part, a chemical substance according to any one of the items of the first aspect of the invention. ° Μ«The organic semiconductor material of the fifth application patent scope, characterized in that the dopant is 2,3,5,6 tetrafluoro·7,7,8,8,.tetracyano-dimethane or derivative. The organic semiconductor material of claim 5 or 6 of the invention is characterized in that the molar doping ratio of the dopant to the matrix material is between ι:ι〇·〇οο.上·1 25