Materials for organic electroluminescent devices

Abstract

The present invention relates to compounds suitable for use in electronic devices, and to electronic devices, especially organic electroluminescent devices, comprising these compounds.

Claims

1. A compound of Formula (3a) ##STR00435## where the symbols and indices used are as follows: Ar.sup.1 is selected from the group consisting of phenyl, biphenyl, terphenyl, quaterphenyl, and fluorenyl; Ar.sup.2 is selected from the group consisting of phenyl, biphenyl, terphenyl, quaterphenyl, fluorenyl, spirobifluorenyl, dibenzofuranyl, and dibenzothienyl; Ar.sup.3 is a group of Formula (2a-1), (2a-2) or (2a-3) ##STR00436## where the dotted bond indicates the linkage of this group to the nitrogen atom and the fluorene group is joined to the nitrogen atom; R.sup.1 in formulae (2a-1), (2a-2) or (2a-3) is the same at each instance and is selected from the group consisting a straight-chain alkyl group having 1 to 4 carbon atoms phenyl and two phenyl groups which together form a ring system and hence a spiro system wherein R.sup.1 radicals on the indenocarbazole are the same or different at each instance and are selected from the group consisting of methyl, phenyl and two phenyl groups which together form a ring system and hence a spiro system.

2. The compound according to claim 1, wherein the R.sup.1 radicals on the indenocarbazole are the same.

3. A formulation comprising at least one compound according to claim 1 and at least one further compound.

4. A formulation comprising at least one compound according to claim 1 and at least one solvent.

5. An electronic device comprising the compound according to claim 1.

6. An organic electroluminescent device which comprises the compound according to claim 1 is used as matrix material for phosphorescent emitters in an emitting layer or in an electron blocker layer or in a hole transport or hole injection layer.

Description

EXAMPLES

Synthesis Examples

(1) The syntheses which follow, unless stated otherwise, are conducted under a protective gas atmosphere in dried solvents. The solvents and reagents can be purchased from ALDRICH or ABCR. The numbers given for the reactants that are not commercially available are the corresponding CAS numbers.

(2) The synthesis of the compounds of the invention is specified by way of example for an example structure in the scheme which follows. Derivatives having other Ar.sup.1, Ar.sup.2, Ar.sup.2, R and R.sup.1 groups are synthesized correspondingly.

(3) ##STR00195## ##STR00196##

Stage 1: Preparation of biphenyl-4-yl(9,9-dimethyl-9H-fluoren-4-yl)amine 3a

(4) In a 2 l four-neck flask, 30.0 g (177 mmol, 1.0 eq) of 4-aminobiphenyl [92-67-1] 1a are initially charged together with 48.4 g (177 mmol, 1.0 eq) of 4-bromo-9,9-dimethyl-9H-fluorene [942615-32-9] 2a and 23.4 g (212 mmol, 1.20 eq) of sodium t-pentoxide [14593-46-5] in 600 ml of absolute toluene and degassed for 30 minutes. Subsequently, 398 mg (1.77 mmol, 0.01 eq) of palladium(II) acetate [3375-31-3] and 1.46 g (3.56 mmol, 0.02 eq) of 2-dicyclohexylphosphino-2′,6′-dimethoxybiphenyl SPHOS [657408-07-6] are added and the mixture is heated under reflux overnight. After the reaction has ended, the mixture is cooled down to room temperature and extracted with 500 ml of water. Subsequently, the aqueous phase is washed three times with toluene, the combined organic phases are dried over sodium sulphate and the solvent is removed on a rotary evaporator. The brown residue is taken up in about 200 ml of toluene and filtered through silica gel. For further purification, a recrystallization from toluene/heptane is conducted. 51.3 g (142 mmol, 80%) of the amine 3a are obtained.

(5) The following are prepared analogously:

(6) TABLE-US-00002 Yield Reactant 1 Reactant 2 Product 3 [%] 3b   [92-67-1]   [89827-45-2] 45 3c 00   [92-67-1] 01   [1225053-54-2] 02 61 3d 03   [92-67-1] 04   [97511-05-2] 05 68 3e 06   [92-67-1] 07   [1415844-67-5] 08 34 3f 09   [92-67-1] 0   [1225053-54-2] 78 3g   [92-67-1]   [86-76-0] 51 3h   [92-67-1]   [50548-45-3] 65 3i   [92-67-1]   [1642127-11-4] 0 81 3j   [92-67-1]   [1190360-23-6] 33 3k   [92-67-1]   [1361227-58-8] 63 3l   [92-67-1]   [1450933-18-2] 23 3m 0   [92-67-1]   [1161009-88-6] 55 3n   [92-67-1]   [1421789-08-3] 68 3o   [18998-24-8]   [50548-45-3] 43 3p   [1579281-06-3] 0   [942615-32-9] 29 3q   [50548-43-1]   [942615-32-9] 34 3r   [72433-66-0]   [97511-05-2] 55 3s   [578027-21-1]   [942615-32-9] 0 62 3t   [578027-21-1]   [1225053-54-2] 72 3u   [50548-43-1]   [1161009-88-6 45

Stage 2: Preparation of (4-bromophenyl)-(9,9-dimethyl-9H-fluoren-4-yl)-{4-[(E)-((Z)-1-propenyl)buta-1,3-dienyl]phenyl}amine 5a

(7) In a 1 l four-neck flask, 51.3 g (142 mmol, 1.00 eq) of the amine 3a and also 75.6 g (426 mmol, 3.00 eq) of 1-bromo-4-fluorobenzene [460-00-4] 4a and 92.5 g (284 mmol, 2.00 eq) of caesium carbonate [534-17-8] are initially charged, and 500 ml of dimethylacetamide are added. The reaction mixture is stirred at 150° C. for three days. After the reaction has ended, the mixture is cooled down to room temperature and the solids are filtered off through Celite. The mother liquor is concentrated and the precipitated solids, after filtration, are extracted by stirring with hot methanol. After drying, 43.5 g (135 mmol, 95%) of the colourless product 5a are obtained.

(8) The following are prepared analogously:

(9) TABLE-US-00003 Reactant 3 Product 5 Yield [%] 5b 78 5c 0 81 5d 94 5e 92 5f 71 5g 88 5h 0 65 5i 79 5j 36 5k 91 5l 26 5m 0 84 5n 68 5o 52 5p 48 5q 67 5r 0 56 5s 44 5t 21 5u 49

Stage 3: Preparation of biphenyl-4-yl[4-(12,12-dimethyl-10,12-dihydro-10-azaindeno[2,1-b]fluoren-7-yl)phenyl](9,9-dimethyl-9H-fluoren-4-yl)amine 7a

(10) In a 2 l four-neck flask, 43.5 g (135 mmol, 1.00 eq) of the amine 5a are initially charged together with 61.0 g (149 mmol, 1.10 eq) of 5,7-dihydro-7,7-dimethyl-2-(44,55-tetramethyl-1,3,2-dioxaborolan-2-yl)-indeno[2,1-b]carbazole [1357286-77-1] and 53.9 g (270 mmol, 2.00 eq) of tripotassium phosphate [7778-53-2], in 300 ml each of toluene and dioxane, and 150 ml of demineralized water, and degassed for 30 minutes. Subsequently, 1.21 g (5.40 mmol, 0.04 eq) of palladium(II) acetate [3375-31-3] and 2.47 g (8.10 mmol, 0.06 eq) of tri-o-tolylphosphine [6163-58-2] are added and the mixture is heated under reflux overnight. After the reaction has ended, a further 100 ml of water are added and the aqueous phase is removed. The aqueous extract is extracted three times with toluene, the combined organic phases are dried over sodium sulphate and the solvent is removed on a rotary evaporator. After recrystallization from toluene/heptane, 81.2 g (113 mmol, 84%) of the desired product 7a are obtained.

(11) The following are prepared analogously:

(12) TABLE-US-00004 Yield Reactant 5 Product 7 [%] 7b 67 7c 00 81 7d 01 02 89 7e 03 04 77 7f 05 06 67 7g 07 08 45 7h 09 0 91 7i 74 7j 66 7k 58 7l 31 7m 0 63 7n 54 7o 87 7p 81 7q 73 7r 0 64 7s 78 7t 93 7u 68

Stage 4: Preparation of biphenyl-4-yl(9,9-dimethyl-9H-fluoren-4-yl)-[4-(12,12-dimethyl-10-phenyl-10,12-dihydro-10-azaindeno[2,1-b]fluoren-7-yl)phenyl]amine 9a

(13) In a 1 l four-neck flask, 20.0 g (25.2 mmol, 1.00 eq) of the intermediate 7a are initially charged together with 11.3 g (55.4 mmol, 2.20 eq) of iodobenzene 8a [591-50-4] and 14.9 g (101 mmol, 4.00 eq) of potassium carbonate [584-08-7] in 300 ml of absolute DMF, and degassed for 30 minutes. Subsequently, 570 mg (2.52 mmol, 0.10 eq) of 1,3-di(2-pyridyl)-1,3-propanedione [10198-89-7] and 480 mg (2.52 mmol, 0.10 eq) of copper(I) iodide [7681-65-4] are added and the mixture is heated under reflux for one day. After the reaction has ended, the reaction mixture is cooled down and transferred gradually into 1000 ml of water. The precipitated solids are filtered off with suction and washed with 400 ml each of saturated ammonium chloride solution, water and 200 ml each of ethanol and heptane. For purification, the solids are subjected to hot extraction with toluene/heptane, recrystallization twice from toluene/heptane and final purification by means of sublimation. 11.2 g (14.1 mmol, 56%) of the desired target compound 9a are obtained with an HPLC purity of >99.9%.

(14) The following are prepared analogously:

(15) TABLE-US-00005 Reactant Yield Reactant 7 8 Product 9 [%] 9b 34 9c 0 51 9d 23 9e 37 9f 0 14 9g 65 9h 47 9i 0 34 9j 52 9k 13 9l 46 9m 0 61 9n 49 9o 19 9p 0 33 9q 23 9r 21 9s 0 55 9t 13 9u 63

Production of the OLEDs

(16) In examples C1 to C9 and I1 to I20 which follow (see Tables 1 and 2), the data of various OLEDs are presented.

Pretreatment for Examples C1-120

(17) Glass plaques coated with structured ITO (indium tin oxide) of thickness 50 nm, for improved processing, are coated with 20 nm of PEDOT:PSS (poly(3,4-ethylenedioxythiophene) poly(styrenesulphonate), purchased as CLEVIOS™ PVP AI 4083 from Heraeus Precious Metals GmbH, Germany, spun on from aqueous solution). These coated glass plaques form the substrates to which the OLEDs are applied.

(18) The OLEDs basically have the following layer structure: substrate/hole transport layer (HTL)/optional interlayer (IL)/electron blocker layer (EBL)/emission layer (EML)/optional hole blocker layer (HBL)/electron transport layer (ETL)/optional electron injection layer (EIL) and finally a cathode. The cathode is formed by an aluminium layer of thickness 100 nm. The exact structure of the OLEDs can be found in Table 1. The materials required for production of the OLEDs are shown in Table 3.

(19) All materials are applied by thermal vapour deposition in a vacuum chamber. In this case, the emission layer always consists of at least one matrix material (host material) and an emitting dopant (emitter) which is added to the matrix material(s) in a particular proportion by volume by co-evaporation. Details given in such a form as IC5:9a:TEG1 (60%:30%:10%) mean here that the material IC5 is present in the layer in a proportion by volume of 60%, 9a in a proportion by volume of 30% and TEG1 in a proportion by volume of 10%. Analogously, the electron transport layer may also consist of a mixture of two materials.

(20) The OLEDs are characterized in a standard manner. For this purpose, the electroluminescence spectra, the current efficiency (measured in cd/A), the power efficiency (measured in lm/W) and the external quantum efficiency (EQE, measured in percent) as a function of luminance, calculated from current-voltage-luminance characteristics (IUL characteristics) assuming Lambertian emission characteristics, and also the lifetime are determined. The electroluminescence spectra are determined at a luminance of 1000 cd/m.sup.2, and the CIE 1931 x and y colour coordinates are calculated therefrom. The parameter U1000 in Table 2 refers to the voltage which is required for a luminance of 1000 cd/m.sup.2. EQE1000 refers to the external quantum efficiency at an operating luminance of 1000 cd/m.sup.2. The lifetime LT is defined as the time after which the luminance drops from the starting luminance to a certain proportion L.sub.1 in the course of operation with constant current. A FIGURE of L.sub.0;j0=4000 cd/m.sup.2 and L.sub.1=70% in Table 2 means that the lifetime reported in the LT column corresponds to the time after which the starting luminance falls from 4000 cd/m.sup.1 to 2800 cd/m.sup.2. Analogously, L.sub.0;j0=20 mA/cm.sup.2, L.sub.1=80% means that the luminance in the course of operation at 20 mA/cm.sup.2 falls to 80% of its starting value after the time LT.

(21) The data for the various OLEDs are collated in Table 2. Examples C1 to C29 are comparative examples according to the prior art; examples I1 to I20 show data of OLEDs of the invention.

(22) Some of the examples are elucidated in detail hereinafter, in order to illustrate the advantages of the OLEDs of the invention.

(23) Use of Mixtures of the Invention in the Emission Layer of Phosphorescent OLEDs

(24) The materials of the invention, when used in the emission layer (EML) of phosphorescent OLEDs, give significant improvements over the prior art, particularly with regard to the lifetime of the OLED components. By use, for example, of the inventive compounds 9a, 9b, 9c and 9h in combination with IC5 and the green dopant TEG1, it is possible to observe an increase in lifetime by more than 40% compared to the prior art PA1-PA9 (comparison of examples C1-C9 with I1-I4). This is also true of the further compounds of the invention, as can be inferred from the examples in Table 2. This is a surprising and unforeseeable result, since the compounds according to the prior art are structurally very similar to the compounds of the invention.

(25) Use of Mixtures of the Invention in the Electron Blocker Layer of Phosphorescent OLEDs

(26) The materials of the invention, when used as electron blocker material in the electron blocker layer of phosphorescent OLEDs as well, give significant improvements over the prior art, particularly with regard to the lifetime. By use of the compounds of the invention, for example of compounds 9f, 9g, 9j, 9k, 9n, 9o and 9t in examples I7, I8, I10, I11, I14, I15 and I20, it is possible to produce OLEDs having improved lifetimes.

(27) TABLE-US-00006 TABLE 1 Structure of the OLEDs HIL IL HTL EBL EML HBL ETL EIL Ex. thickness thickness thickness thickness thickness thickness thickness thickness C1 SpA1 HATCN SpMA1 — IC5:PA1:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 70 nm (60%:30%:10%) 30 nm 10 nm (50%:50%) 30 nm C2 SpA1 HATCN SpMA1 — IC5:PA2:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 70 nm (60%:30%:10%)30 nm 10 nm (50%:50%) 30 nm C3 SpA1 HATCN SpMA1 — IC5:PA3:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 70 nm (60%:30%:10%)30 nm 10 nm (50%:50%) 30 nm C4 SpA1 HATCN SpMA1 — IC5:PA4:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 70 nm (60%:30%:10%)30 nm 10 nm (50%:50%) 30 nm C5 SpA1 HATCN SpMA1 — IC5:PA5:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 70 nm (60%:30%:10%)30 nm 10 nm (50%:50%) 30 nm C6 SpA1 HATCN SpMA1 — IC5:PA6:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 70 nm (60%:30%:10%)30 nm 10 nm (50%:50%) 30 nm C7 SpA1 HATCN SpMA1 — IC5:PA7:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 70 nm (60%:30%:10%) 30 nm 10 nm (50%:50%) 30 nm C8 SpA1 HATCN SpMA1 — IC5:PA8:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 70 nm (60%:30%:10%) 30 nm 10 nm (50%:50%) 30 nm C9 SpA1 HATCN SpMA1 — IC5:PA9:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 70 nm (60%:30%:10%) 30 nm 10 nm (50%:50%) 30 nm I1 SpA1 HATCN SpMA1 — IC5:9a:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 70 nm (60%:30%:10%) 30 nm 10 nm (50%:50%) 30 nm I2 SpA1 HATCN SpMA1 — IC5:9b:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 70 nm (60%:30%:10%) 30 nm 10 nm (50%:50%) 30 nm I3 SpA1 HATCN SpMA1 — IC5:9c:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 70 nm (60%:30%:10%) 30 nm 10 nm (50%:50%) 30 nm I4 SpA1 HATCN SpMA1 — IC5:9h:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 70 nm (60%:30%:10%) 30 nm 10 nm (50%:50%) 30 nm I5 SpA1 HATCN SpMA1 — IC5:9d:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 70 nm (60%:30%:10%) 30 nm 10 nm (50%:50%) 30 nm I6 SpA1 HATCN SpMA1 — IC5:9e:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 70 nm (60%:30%:10%) 30 nm 10 nm (50%:50%) 30 nm I7 SpA1 HATCN SpMA1 9f IC5:IC3:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 50 nm 20 nm (45%:45%:10%) 30 nm 10 nm (50%:50%) 30 nm I8 SpA1 HATCN SpMA1 9g IC5:IC3:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 50 nm 20 nm (45%:45%:10%) 30 nm 10 nm (50%:50%) 30 nm I9 SpA1 HATCN SpMA1 — IC5:9u:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 70 nm (50%:40%:10%) 30 nm 10 nm (50%:50%) 30 nm I10 SpA1 HATCN SpMA1 9j IC5:IC3:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 50 nm 20 nm (45%:45%:10%) 30 nm 10 nm (50%:50%) 30 nm I11 SpA1 HATCN SpMA1 9k IC5:IC3:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 50 nm 20 nm (45%:45%:10%) 30 nm 10 nm (50%:50%) 30 nm I12 SpA1 HATCN SpMA1 — IC5:9l:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 70 nm (60%:30%:10%) 30 nm 10 nm (50%:50%) 30 nm I13 SpA1 HATCN SpMA1 9m IC5:9m:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 50 nm 20 nm (60%:30%) 30 nm 10 nm (50%:50%) 30 nm I14 SpA1 HATCN SpMA1 9n IC1:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 50 nm 20 nm (60%:30%:10%) 30 nm 10 nm (50%:50%) 30 nm I15 SpA1 HATCN SpMA1 9o IC1:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 50 nm 20 nm (90%:10%) 30 nm 10 nm (50%:50%) 30 nm I16 SpA1 HATCN SpMA1 9p IC5:9p:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 50 nm 20 nm (90%:10%) 30 nm 10 nm (50%:50%) 30 nm I17 SpA1 HATCN SpMA1 — IC5:9q:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 70 nm (60%:30%:10%) 30 nm 10 nm (50%:50%) 30 nm I18 SpA1 HATCN SpMA1 — IC5:9r:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 70 nm (60%:30%:10%)30 nm 10 nm (50%:50%) 30 nm I19 SpA1 HATCN SpMA1 9s IC5:9s:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 50 nm 20 nm (60%:30%:10%) 30 nm 10 nm (50%:50%) 30 nm I20 SpA1 HATCN SpMA1 9t IC5:IC3:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 50 nm 20 nm (45%:45%:10%) 30 nm 10 nm (50%:50%) 30 nm I21 SpA1 HATCN SpMA1 — IC5:9f:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 70 nm (60%:30%:10%) 30 nm 10 nm (50%:50%) 30 nm I22 SpA1 HATCN SpMA1 — IC5:9g:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 70 nm (60%:30%:10%) 30 nm 10 nm (50%:50%) 30 nm I23 SpA1 HATCN SpMA1 — IC5:9j:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 70 nm (60%:30%:10%) 30 nm 10 nm (50%:50%) 30 nm I24 SpA1 HATCN SpMA1 — IC5:9k:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 70 nm (60%:30%:10%) 30 nm 10 nm (50%:50%) 30 nm I25 SpA1 HATCN SpMA1 — IC5:9n:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 70 nm (60%:30%:10%) 30 nm 10 nm (50%:50%) 30 nm I26 SpA1 HATCN SpMA1 — IC5:9o:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 70 nm (60%:30%:10%) 30 nm 10 nm (50%:50%) 30 nm I27 SpA1 HATCN SpMA1 — IC5:9t:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 70 nm (60%:30%:10%) 30 nm 10 nm (50%:50%) 30 nm I28 SpA1 HATCN SpMA1 — IC5:9m:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 70 nm (60%:30%:10%) 30 nm 10 nm (50%:50%) 30 nm I29 SpA1 HATCN SpMA1 — IC5:9p:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 70 nm (60%:30%:10%) 30 nm 10 nm (50%:50%) 30 nm I30 SpA1 HATCN SpMA1 — IC5:9s:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 70 nm (60%:30%:10%) 30 nm 10 nm (50%:50%) 30 nm I31 SpA1 HATCN SpMA1 — IC5:9u:TEG1 ST2 ST2:LiQ — 70 nm 5 nm 70 nm (60%:30%:10%) 30 nm 10 nm (50%:50%) 30 nm

(28) TABLE-US-00007 TABLE 2 Data of the OLEDs U1000 EQE LT Ex. (V) 1000 L.sub.0; j.sub.0 L.sub.1 % (h) C1 3.1 15.3% 20 mA/cm.sup.2 80 130 C2 3.2 15.4% 20 mA/cm.sup.2 80 120 C3 3.2 15.2% 20 mA/cm.sup.2 80 140 C4 3.3 15.5% 20 mA/cm.sup.2 80 110 C5 3.1 15.6% 20 mA/cm.sup.2 80 105 C6 3.2 15.7% 20 mA/cm.sup.2 80 100 C7 3.1 15.6% 20 mA/cm.sup.2 80 115 C8 3.2 15.1% 20 mA/cm.sup.2 80 75 C9 3.1 15.8% 20 mA/cm.sup.2 80 125 I1 3.2 16.1% 20 mA/cm.sup.2 80 260 I2 3.3 16.3% 20 mA/cm.sup.2 80 230 I3 3.3 16.2% 20 mA/cm.sup.2 80 240 I4 3.2 16.0% 20 mA/cm.sup.2 80 255 I5 3.3 16.2% 20 mA/cm.sup.2 80 235 I6 3.2 16.1% 20 mA/cm.sup.2 80 225 I7 3.2 16.7% 20 mA/cm.sup.2 80 265 I8 3.3 16.5% 20 mA/cm.sup.2 80 225 I9 3.4 16.2% 20 mA/cm.sup.2 80 250 I10 3.4 16.6% 20 mA/cm.sup.2 80 225 I11 3.5 16.5% 20 mA/cm.sup.2 80 220 I12 3.1 16.0% 20 mA/cm.sup.2 80 210 I13 3.3 16.3% 20 mA/cm.sup.2 80 245 I14 3.5 17.4% 20 mA/cm.sup.2 80 125 I15 3.4 17.5% 20 mA/cm.sup.2 80 115 I16 3.4 16.2% 20 mA/cm.sup.2 80 255 I17 3.3 16.0% 20 mA/cm.sup.2 80 250 I18 3.3 16.1% 20 mA/cm.sup.2 80 245 I19 3.3 16.2% 20 mA/cm.sup.2 80 240 I20 3.3 16.5% 20 mA/cm.sup.2 80 270 I21 3.4 15.6% 20 mA/cm.sup.2 80 150 I22 3.4 15.5% 20 mA/cm.sup.2 80 155 I23 3.3 15.8% 20 mA/cm.sup.2 80 160 I24 3.4 15.9% 20 mA/cm.sup.2 80 150 I24 3.4 16.1% 20 mA/cm.sup.2 80 145 I25 3.3 16.0% 20 mA/cm.sup.2 80 220 I26 3.4 15.7% 20 mA/cm.sup.2 80 155 I27 3.4 16.1% 20 mA/cm.sup.2 80 230 I28 3.5 16.2% 20 mA/cm.sup.2 80 245 I29 3.3 16.0% 20 mA/cm.sup.2 80 250 I30 3.4 16.2% 20 mA/cm.sup.2 80 235

(29) TABLE-US-00008 TABLE 3 Structural formulae of the materials for the OLEDs 00 01 02 03 04 05 06 07 08 09 0 0 0