COMPOUND, MATERIAL FOR AN ORGANIC ELECTROLUMINESCENCE DEVICE AND AN ORGANIC ELECTROLUMINESCENCE DEVICE COMPRISING THE COMPOUND

Abstract

Specific compounds represented by formula (1), a material for an organic electroluminescence device comprising said specific compound, an organic electroluminescence device comprising said specific compound, an electronic equipment comprising said organic electroluminescence device and the use of said compounds in an organic electroluminescence device.

##STR00001##

Claims

1. A compound represented by formula (I): ##STR00075## wherein L represents an unsubstituted divalent aromatic hydrocarbon group containing 6 to 30 ring atoms or an unsubstituted divalent heteroaromatic group containing 3 to 30 ring atoms; Ar.sub.1, Ar.sub.2 and Ar.sub.3 each independently represents an unsubstituted or substituted aromatic hydrocarbon group containing 6 to 30 ring atoms or an unsubstituted or substituted heteroaromatic group containing 3 to 30 ring atoms, wherein at least one of Ar.sub.1 and Ar.sub.2 is substituted by at least one group Az.sub.1 or Az.sub.2; Az.sub.1 and Az.sub.2 each independently represents an unsubstituted or substituted heteroaromatic group containing 3 to 30 ring atoms containing at least one ring nitrogen; R.sub.a and R.sub.b each independently represents hydrogen, an unsubstituted or substituted aromatic hydrocarbon group containing 6 to 30 ring atoms or an unsubstituted or substituted heteroaromatic group containing 3 to 30 ring atoms, an unsubstituted or substituted alkyl group having 1 to 25 carbon atoms, an unsubstituted or substituted cycloalkyl group having 3 to 18 ring carbon atoms or CN, or two adjacent groups R.sub.a, and/or two adjacent groups R.sub.b, can form together a substituted or unsubstituted carbocyclic or heterocyclic ring; p is 1, 2 or 3; m and n are each independently 0, 1, 2, 3 or 4, wherein at least one of m and n is not 0; s is 0, 1, 2 or 3; and t is 0, 1, 2, 3 or 4.

2. The compound according to claim 1, wherein L represents an unsubstituted divalent aromatic hydrocarbon group containing 6 to 30 ring atoms.

3. The compound according to claim 1, wherein p is 1 or 2.

4. The compound according to claim 1, wherein m and n are each independently 0, 1 or 2, wherein at least one of m and n is not 0.

5. The compound according to claim 1, wherein—in the case that n respectively m is 0—Ar.sub.1 respectively Ar.sub.2 is an unsubstituted or substituted phenyl group or an unsubstituted or substituted naphthyl group or an unsubstituted or substituted fluorene group.

6. The compound according to claim 1, wherein—in the case that m respectively n is not 0—Ar.sub.1 respectively Ar.sub.2 is an unsubstituted or substituted phenylene group, an unsubstituted or substituted fluorene-diyl group, or an unsubstituted or substituted naphthylene group.

7. The compound according to claim 1, wherein Az.sub.1 and Az.sub.2 each independently represents pyridyl, a quinoline group, a phenanthroline group, a pyridazine group, a pyrimidine group, a pyrazine group, a triazine group, a isoquinoline group, a quinolizine group, a cinnoline group, a quinoxaline group, a quinazoline group, a phthalazine group, a naphthyridine group, an acridine group, a phenanthridine group, a phenazine group, a pteridine group, a thiazole group, an oxazole group, an imidazole group, a benzothiazole group, a benzoxazole group, a benzimidazole group, an imidazopyridine group wherein the aforementioned groups are unsubstituted or substituted.

8. The compound according to claim 1, wherein R.sub.a and R.sub.b each independently represents hydrogen, an unsubstituted or substituted aromatic hydrocarbon group containing 6 to 30 ring atoms or an unsubstituted or substituted heteroaromatic group containing 3 to 30 ring atoms, or CN.

9. A material for an organic electroluminescence device, comprising at least one compound according to claim 1.

10. An organic electroluminescence device comprising at least one compound according to claim 1.

11. The organic electroluminescence device according to claim 10, the organic electroluminescence device further comprising: a cathode, an anode, and one or more organic thin film layers comprising an emitting layer disposed between the cathode and the anode, wherein the organic thin film layers comprise an electron-transporting zone provided between the emitting layer and the cathode, and wherein the electron-transporting zone comprises the at least one compound.

12. The organic electroluminescence device according to claim 11, wherein the electron-transporting zone further comprises an electron-transporting layer provided between the emitting layer and the cathode, and wherein the electron-transporting layer comprises the at least one compound according to claim 1.

13. The organic electroluminescence device according to claim 11, wherein the electron-transporting zone further comprises at least one organic metal complex or compound.

14. An electronic equipment comprising the organic electroluminescence device according to claim 10.

Description

EXAMPLES

I Preparation Examples

[0272] Compound 1

[0273] Step 1

##STR00058##

[0274] In a 2l three-necked, round bottomed flask were placed (9-phenyl-9H-carbazol-3-yl)boronic acid (52 g, 181 mmol) followed by 1-bromo-4-iodobenzene (56.4 g, 199 mmol), K.sub.2CO.sub.3 (75 g, 543 mmol), Toluene (500 ml) THE (250 ml) and water (125 ml). The reaction mixture was evacuated and back filled with Argon 5 times. Pd(PPh.sub.3).sub.4(6.28 g, 5.43 mmol) was added, the mixture was evacuated and back filled with Argon 5 times and heated to reflux overnight. The reaction mixture was then diluted with 500 ml Toluene, cooled to 50° C., the phases were separated and the THF evaporated. The Toluene phase was washed 3× with H.sub.2O (200 ml each), 1× with 100 ml brine, dried over MgSO.sub.4 and 60 g silica was added. The suspension was stirred for 15 min, filtered, washed 3× with Toluene (100 ml each) and concentrated to yield 87.37 g of a yellow oil. 1600 ml 2-Propanol was added. The mixture was heated to reflux and a suspension was formed. Stirred for 1 h, then cooled to RT with stirring. The suspension was filtered, the filter cake was washed 2× with ice cold 2-Propanol (50 ml each) and 2× with ice cold MeoH (100 ml each). Dried at 80° C./125 mbar overnight to yield 65.9 g (91.4% of theory) of Intermediate 1 as a white solid.

[0275] .sup.1H NMR (300 MHz, Tetrachloroethane-d.sub.2) δ 8.28 (d, J=1.7 Hz, 1H), 8.17 (dt, J=7.8, 1.1 Hz, 1H), 7.68-7.53 (m, 9H), 7.52-7.40 (m, 4H), 7.30 (dt, J=8.0, 4.1 Hz, 1H).

[0276] Step 2

##STR00059##

[0277] A 1l three necked round-bottomed flask with magnetic stirrer and thermometer was charged with Intermediate 1 (22 g, 55.2 mmol), followed by THE (600 ml). The coulourless, clear solution was cooled with an Aceton/dry ice-bath to −74° C. under Argon, before 2.5M n-BuLi (26.5 ml, 66.3 mmol) was added slowly within 15 min. keeping the internal temperature between −76 and −73° C. The yellow solution was stirred at −74° C. for 1h.

[0278] A 2l three necked round-bottomed flask with magnetic stirrer and thermometer was charged with 2,4-dichloro-6-phenyl-1,3,5-triazine (31.2 g, 138 mmol), and THE (600 ml). The solution was cooled with an Aceton/dry ice-bath to −76° C., before the solution from step 1 was added slowly over a period of 40 min (internal temperature −76° C. to −73° C. during addition) with a canula. The reaction mixture was stirred at −75° C. for 1 h, then warmed to RT. The reaction mixture was concentrated to 100 ml solution, then added slowly to 2l MeOH under vigorous stirring. The suspension was stirred for 10 min, then filtered and the filter cake was washed 2× with MeOH (100 ml each).

[0279] The residue was dried at RT/125 mbar over the weekend to yield 12.5 g (44.5% of theory) of Intermediate 2 as a yellow solid.

[0280] 1H NMR (300 MHz, Tetrachloroethane-d2) δ 8.73-8.67 (m, 2H), 8.65-8.58 (m, 2H), 8.43 (d, J=1.7 Hz, 1H), 8.21 (dd, J=7.7, 1.1 Hz, 1H), 7.94-7.87 (m, 2H), 7.74 (dd, J=8.6, 1.8 Hz, 1H), 7.66-7.42 (m, 11H), 7.32 (ddd, J=8.0, 4.7, 3.5 Hz, 1H).

[0281] Step 3

##STR00060##

[0282] A 250 ml three necked round-bottomed flask with magnetic stirrer, thermometer and reflux condenser was charged with Intermediate 2 (7 g, 12.38 mmol), (4-chlorophenyl)boronic acid (1.55 g, 9.90 mmol), K.sub.2CO.sub.3 (5.13 g, 37.1 mmol) followed by Toluene (70 ml), THE (35 ml) and Water (17.5 ml). The reaction mixture was evacuated and backfilled with Argon five times. Pd(PPh.sub.3).sub.4(0.715 g, 0.619 mmol) was added and the reaction mixture was evacuated and backfilled with Argon five times. The yellow suspension was heated to reflux and a yellow solution was formed that was stirred overnight. The yellow suspension was cooled to RT, filtered and washed with ice cold Toluene, MeOH, H.sub.2O and again with MeOH. The filter cake was dried at ambient conditions overnight to yield 4.67 g of crude product that was crystallized from Toluene to yield 3.85 g (53% of theory) of Intermediate 3 as a yellow solid.

[0283] .sup.1H NMR (300 MHz, Tetrachloroethane-d.sub.2) δ 8.87-8.68 (m, 6H), 8.45 (d, J=1.9 Hz, 1H), 8.21 (d, J=7.7 Hz, 1H), 7.98-7.89 (m, 2H), 7.76 (dd, J=8.6, 1.8 Hz, 1H), 7.66-7.41 (m, 13H), 7.33 (dq, J=8.1, 4.4 Hz, 1H).

[0284] Step 4

##STR00061##

[0285] In a 250 ml three necked round-bottomed flask with magnetic stirrer, thermometer and reflux condenser were placed Intermediate 3 (6.03 g, 10.31 mmol), Bis(pinacolato) diboron (6.54 g, 25.8 mmol), Potassium acetate (2.53 g, 25.8 mmol) and Dioxane (150 ml). The yellow suspension was evacuated and backfilled with Argon 5 times. Then Argon was bubbled through the suspension for 40 min. Pd.sub.2(dba).sub.3 (0.142 g, 0.155 mmol) and s-Phos (0.127 g, 0.309 mmol) were added and the red suspension was evacuated and backfilled with argon 5 times. The reaction mixture was heated to reflux overnight, then filtered hot through Hyflo and washed 2× with EtOAc (40 ml each). The filtrate was concentrated to yield 12.39 g of an orange foam. 200 ml MeOH was added to the residue, put in an ultra sonic bath for 30 min. The suspension was cooled with stirring, filtered, washed 3× with MeOH (20 ml each) and dried at RT/125 mbar overnight to yield 6.8 g (98%) of Intermediate 4 as a beige solid.

[0286] .sup.1H NMR (300 MHz, Tetrachloroethane-d.sub.2) δ 8.88-8.71 (m, 6H), 8.46 (d, J=1.7 Hz, 1H), 8.22 (dt, J=7.7, 1.0 Hz, 1H), 8.04-7.91 (m, 4H), 7.77 (dd, J=8.6, 1.8 Hz, 1H), 7.66-7.56 (m, 7H), 7.54-7.42 (m, 4H), 7.32 (dt, J=7.9, 4.0 Hz, 1H), 1.35 (s, 12H).

[0287] Step 5

##STR00062##

[0288] In a 250 ml three necked round-bottomed flask with magnetic stirrer, thermometer and reflux condenser were placed 3-chloropyridine (0.843 ml, 8.87 mmol), Intermediate 4 (6.0 g, 8.87 mmol) and potassium carbonate (2.92 g, 21.10 mmol) in Dioxane (40 ml), Toluene (78 ml) and H.sub.2O (30 ml). The pink suspension was bubbled with argon for 60 min. Pd(OAc).sub.2 (0.038 g, 0.168 mmol) and dicyclohexyl(2′,4′,6′-triisopropyl-[1,1′-biphenyl]-2-yl)phosphane (0.161 g, 0.337 mmol) were added and the reaction mixture was evacuated and backfilled with argon 5 times. The brown suspension was heated to reflux and reacted overnight. The reaction mixture was filtered hot through Hyflo and the two phases of the filtrate were separated. The organic phase was washed three times with water, dried with MgSO.sub.4, filtered and concentrated to yield 8.28 g of a yellow solid. The crude product was crystallized from Xylene to yield 4.04 g (72.6%) of Compound 1 as a yellow solid.

[0289] .sup.1H NMR (300 MHz, Tetrachloroethane-d.sub.2) δ 8.94-8.84 (m, 5H), 8.82-8.77 (m, 2H), 8.62 (dd, J=4.8, 1.6 Hz, 1H), 8.46 (d, J=1.8 Hz, 1H), 8.22 (dt, J=7.7, 1.1 Hz, 1H), 8.02-7.92 (m, 3H), 7.83-7.74 (m, 3H), 7.65-7.56 (m, 7H), 7.51 (dd, J=8.6, 6.8 Hz, 2H), 7.43 (ddd, J=9.0, 4.7, 1.0 Hz, 3H), 7.33 (dt, J=8.0, 4.1 Hz, 1H).

[0290] Compound 2

[0291] Step 1

##STR00063##

[0292] A 250 ml three necked round-bottomed flask with magnetic stirrer, thermometer and reflux condenser was charged with Intermediate 2 (9.94 g, 17.58 mmol), (3-chlorophenyl)boronic acid (2.199 g, 14.06 mmol), K.sub.2CO.sub.3 (7.29 g, 52.7 mmol) followed by Toluene (100 ml), THE (50 ml) and H.sub.2O (25 ml). The reaction mixture was evacuated and backfilled with Argon five times. Pd(PPh.sub.3).sub.4(1.015 g, 0.879 mmol) was added and the reaction mixture was evacuated and backfilled with Argon five times. The yellow suspension was heated to reflux and a orange solution was formed that was stirred overnight. The yellow suspension was cooled to RT, then to 0° C. with an ice bath, filtered and washed with ice cold Toluene, MeOH, H.sub.2O and again with MeOH. The filter cake was dried at 80° C./125 mbar overnight to yield 6.31 g of crude product that was crystallized from Toluene to yield 5.81 g (57% of theory) of Intermediate 5 as a slightly yellow solid.

[0293] .sup.1H NMR (300 MHz, Tetrachloroethane-d.sub.2) δ 8.87-8.65 (m, 6H), 8.45 (d, J=1.7 Hz, 1H), 8.22 (dd, J=7.7, 1.0 Hz, 1H), 7.98-7.90 (m, 2H), 7.76 (dd, J=8.6, 1.8 Hz, 1H), 7.65-7.40 (m, 13H), 7.32 (dt, J=8.0, 4.1 Hz, 1H).

[0294] Step 2

##STR00064##

[0295] The synthesis of Compound 1, Step 4 was repeated, but using Intermediate 5 (5.81 g, 9.93 mmol) instead of Intermediate 3 to yield 6.7 g (100%) of Intermediate 6 as a beige solid.

[0296] .sup.1H NMR (300 MHz, Tetrachloroethane-d.sub.2) δ 9.07 (t, J=1.5 Hz, 1H), 8.89-8.82 (m, 3H), 8.78 (ddd, J=5.5, 4.4, 2.7 Hz, 2H), 8.46 (d, J=1.8 Hz, 1H), 8.22 (dt, J=7.7, 1.0 Hz, 1H), 8.06 (dt, J=7.3, 1.3 Hz, 1H), 7.99-7.92 (m, 2H), 7.77 (dd, J=8.6, 1.9 Hz, 1H), 7.65-7.57 (m, 8H), 7.55-7.47 (m, 2H), 7.44 (d, J=3.8 Hz, 2H), 7.32 (dt, J=8.0, 4.1 Hz, 1H), 3.41 (s, 12H).

[0297] Step 3

##STR00065##

[0298] The synthesis of Compound 1, Step 5 was repeated, but using Intermediate 6 (5 g, 7.39 mmol) instead of Intermediate 4 to yield 2.15 g (46.4%) of Compound 2 as a slightly yellow solid.

[0299] .sup.1H NMR (300 MHz, Tetrachloroethane-d.sub.2) δ 9.00 (dt, J=3.2, 1.4 Hz, 2H), 8.91-8.76 (m, 5H), 8.63 (dd, J=4.8, 1.6 Hz, 1H), 8.46 (d, J=1.8 Hz, 1H), 8.21 (dt, J=7.7, 1.1 Hz, 1H), 8.05 (ddd, J=7.9, 2.4, 1.7 Hz, 1H), 7.99-7.92 (m, 2H), 7.87-7.54 (m, 11H), 7.52-7.43 (m, 4H), 7.33 (dt, J=7.9, 4.0 Hz, 1H).

[0300] Compound 3

[0301] Step 1

##STR00066##

[0302] The synthesis of Compound 1, Step 5 was repeated, but using Intermediate 6 (5 g, 7.39 mmol) instead of Intermediate 4 and 4′-chloro-2,2′:6′,2″-terpyridine (1.89 g, 7.04 mmol) instead of 3-chloropyridine to yield 3.57 g (61.8%) of Compound 3 as a slightly yellow solid.

[0303] .sup.1H NMR (300 MHz, Tetrachloroethane-d.sub.2) δ 9.19 (t, J=1.8 Hz, 1H), 8.91-8.66 (m, 11H), 8.45 (d, J=1.7 Hz, 1H), 8.24-8.18 (m, 1H), 8.11 (dt, J=8.0, 1.3 Hz, 1H), 7.98-7.87 (m, 4H), 7.80-7.72 (m, 2H), 7.66-7.56 (m, 7H), 7.54-7.31 (m, 7H).

[0304] Compound 4

[0305] Step 1

##STR00067##

[0306] The synthesis of Compound 1, Step 5 was repeated, but using Intermediate 6 (6.82 g, 10.08 mmol) instead of Intermediate 4 and 2-bromo-1,10-phenanthroline (5.22 g, 20.16 mmol) instead of 3-chloropyridine to yield 6.61 g (89.9%) of Compound 4 as a slightly yellow solid.

[0307] 1H NMR (300 MHz, Tetrachloroethane-d2) δ 9.55 (t, J=1.9 Hz, 1H), 9.23 (dd, J=4.4, 1.8 Hz, 1H),

[0308] 8.91 (dd, J=8.8, 7.0 Hz, 3H), 8.87-8.78 (m, 2H), 8.73 (dt, J=7.7, 1.5 Hz, 1H), 8.46 (d, J=1.8 Hz,

[0309] 1H), 8.39 (d, J=8.4 Hz, 1H), 8.33-8.25 (m, 2H), 8.22 (dd, J=7.7, 1.1 Hz, 1H), 8.01-7.91 (m, 2H),

[0310] 7.88-7.72 (m, 4H), 7.72-7.56 (m, 8H), 7.56-7.40 (m, 4H), 7.33 (dt, J=7.9, 4.1 Hz, 1H).

[0311] Compound 5

[0312] Step 1

##STR00068##

[0313] In a 100 mL three-necked, round bottomed flask were placed (4-(9-phenyl-9H-carbazol-4-yl)phenyl)boronic acid (6.13 g, 16.88 mmol) followed by 2-([1,1′-biphenyl]-2-yl)-4,6-dichloro-1,3,5-triazine (3.4 g, 11.25 mmol), Na.sub.2CO.sub.3 (2.98 g, 28.1 mmol), Toluene (56 ml) and water (14 ml). The reaction mixture was evacuated and back filled with Argon 5 times. PdCl.sub.2(PPh.sub.3).sub.2 (0.079 g, 0.11 mmol) was added, the mixture was evacuated and back filled with Argon 5 times and heated to reflux overnight. The reaction mixture was cooled to room temperature and the solvent was evaporated. The crude material was purified by silica gel chromatography, eluting with Hexane and CH.sub.2Cl.sub.2 to obtain Intermediate 8 as a pale yellow solid (3.87 g, 58.8% yield). As a result of mass spectroscopy, it was found that m/e=585 and the compound was identified to be the above Intermediate 8 (Exact mass: 584.17).

[0314] Step 2

##STR00069##

[0315] The synthesis of Compound 2, Step 1 was repeated, but using 3-(3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)pyridine (2.42 g, 8.60 mmol) instead of (3-chlorophenyl)boronic acid and Intermediate 8 (3.87 g, 6.61 mmol) instead of Intermediate 2 to yield 1.86 g (38.4%) of Compound 5 as a slightly yellow solid.

[0316] As a result of mass spectroscopy, it was found that m/z=704 and the compound was identified to be the above Compound 5 (Exact mass: 703.27).

[0317] Comparative Compound 1

[0318] Step 1

##STR00070##

[0319] The synthesis of Compound 1, Step 4 was repeated, but using 3-(4-chlorophenyl)-9-phenyl-9H-carbazole (11 g, 31.1 mmol) instead of Intermediate 3 to yield 10.39 g (75%) of Intermediate 7 as a beige solid.

[0320] .sup.1H NMR (300 MHz, Tetrachloroethane-d.sub.2) δ 8.34 (d, J=1.8 Hz, 1H), 8.18 (dd, J=7.7, 1.1 Hz, 1H), 7.93-7.87 (m, 2H), 7.73-7.55 (m, 7H), 7.49-7.40 (m, 4H), 7.29 (ddd, J=8.0, 4.7, 3.5 Hz, 1H), 1.33 (s, 12H).

[0321] Step 2

##STR00071##

[0322] The synthesis of Compound 2, Step 1 was repeated, but using Intermediate 7 (9.84 g, 22.1 mmol) instead of (3-chlorophenyl)boronic acid and 2-([1,1′-biphenyl]-4-yl)-4-chloro-6-phenyl-1,3,5-triazine (9.12 g, 26.5 mmol) instead of Intermediate 2 to yield 3.37 g (24.3%) of Comparative Compound 1 as a slightly yellow solid.

[0323] .sup.1H NMR (300 MHz, Tetrachloroethane-d.sub.2) δ 8.93-8.81 (m, 4H), 8.82-8.75 (m, 2H), 8.46 (d, J=1.8 Hz, 1H), 8.27-8.18 (m, 1H), 8.00-7.90 (m, 2H), 7.86-7.80 (m, 2H), 7.77 (dd, J=8.6, 1.8 Hz, 1H), 7.74-7.68 (m, 2H), 7.68-7.55 (m, 7H), 7.55-7.37 (m, 7H), 7.33 (dt, J=7.9, 4.0 Hz, 1H).

II Application Examples

Application Example 1

[0324] A glass substrate with 130 nm-thick indium-tin-oxide (ITO) transparent electrode (manufactured by Geomatec Co., Ltd.) used as an anode was first treated with N2 plasma for 100 sec. This treatment also improved the hole-injection properties of the ITO. The cleaned substrate was mounted on a substrate holder and loaded into a vacuum chamber. Thereafter, the organic materials specified below were applied by vapor deposition to the ITO substrate at a rate of approx. 0.2-1 Å/sec at about 10.sup.−6-10.sup.−8 mbar. As a hole-injection layer, 10 nm-thick mixture of Compound HT and 3% by weight of Compound HI were applied. Then 80 nm-thick of Compound HT and 5 nm of Compound EB were applied as hole-transporting layer 1 and electron-blocking layer, respectively. Subsequently, a mixture of 1% by weight of an emitter Compound BD-1 and 99% by weight of host Compound BH-1 were applied to form a 20 nm-thick fluorescent-emitting layer. On the emitting layer, 5 nm-thick Compound HB was applied as an hole-blocking layer and 25 nm of Compound 1 as electron transporting layer. Finally, 1 nm-thick Yb was deposited as an electron injection layer and 50 nm-thick Al was then deposited as a cathode to complete the device. The device was sealed with a glass lid and a getter in an inert nitrogen atmosphere with less than 1 ppm of water and oxygen. To characterize the OLED, electroluminescence spectra were recorded at various currents and voltages. In addition, the current-voltage characteristic was measured. Lifetime of OLED device was measured as a decay of the luminance at constant current density of 50 mA/cm.sup.2 to 95% of its initial value. Voltage rise was measured at constant current density of 50 mA/cm.sup.2 after 100h, relative to initial voltage. The device results are shown in Table 1.

##STR00072## ##STR00073## ##STR00074##

Application Example 2

[0325] Application Example 1 was repeated except for using the Compound 2 in place of Compound 1 in the electron transporting layer.

Application Example 3

[0326] Application Example 1 was repeated except for using the Compound 3 in place of Compound 1 in the electron transporting layer.

Comparative Application Example 1

[0327] Application Example 1 was repeated except for using the Comparative Compound 1 in place of Compound 1 in the electron transporting layer.

Comparative Application Example 2

[0328] Application Example 1 was repeated except for using the Comparative Compound 2 in place of Compound 1 in the electron transporting layer.

[0329] The device results are shown in Table 1.

TABLE-US-00001 Electron Voltage transporting LT95 at 50 rise at 100 Appl. Ex. layer mA/cm.sup.2, h hours, V Appl. Ex. 1 Compound 1 164 0.02 Appl. Ex. 2 Compound 2 152 0.03 Appl. Ex. 3 Compound 3 139 0.07 Comp. Appl. Comparative 47 0.23 Ex. 1 Compound 1 Comp. Appl. Comparative 107 0.35 Ex. 2 Compound 2

[0330] These results demonstrate that lifetime and voltage rise are improved in the case that the inventive Compounds are used instead of the Comparative Compounds 1 and 2 as the electron transporting material with Yb as electron injecting layer.

Application Example 4

[0331] A glass substrate with 130 nm-thick indium-tin-oxide (ITO) transparent electrode (manufactured by Geomatec Co., Ltd.) used as an anode was first treated with N2 plasma for 100 sec. This treatment also improved the hole-injection properties of the ITO. The cleaned substrate was mounted on a substrate holder and loaded into a vacuum chamber. Thereafter, the organic materials specified below were applied by vapor deposition to the ITO substrate at a rate of approx. 0.2-1 Å/sec at about 10.sup.−6-10.sup.−8 mbar. As a hole-injection layer, 10 nm-thick mixture of Compound HT and 3% by weight of Compound HI were applied. Then 80 nm-thick of Compound HT and 5 nm of Compound EB were applied as hole-transporting layer 1 and electron-blocking layer, respectively. Subsequently, a mixture of 1% by weight of an emitter Compound BD-1 and 99% by weight of host Compound BH-1 were applied to form a 20 nm-thick fluorescent-emitting layer. On the emitting layer, 5 nm-thick Compound HB was applied as an hole-blocking layer and 25 nm of Compound 1 as electron transporting layer. Finally, 1 nm-thick LiF was deposited as an electron injection layer and 50 nm-thick Al was then deposited as a cathode to complete the device. The device was sealed with a glass lid and a getter in an inert nitrogen atmosphere with less than 1 ppm of water and oxygen. To characterize the OLED, electroluminescence spectra were recorded at various currents and voltages. Voltages are reported at 10 mA/cm.sup.2. Lifetime of OLED device was measured as a decay of the luminance at constant current density of 50 mA/cm.sup.2 to 95% of its initial value. The device results are shown in Table 2.

Application Example 5

[0332] Application Example 4 was repeated except for using the Compound 2 in place of Compound 1 in the electron transporting layer.

Application Example 6

[0333] Application Example 4 was repeated except for using the Compound 3 in place of Compound 1 in the electron transporting layer.

Comparative Application Example 3

[0334] Application Example 4 was repeated except for using the Comparative Compound 1 in place of Compound 1 in the electron transporting layer.

[0335] The device results are shown in Table 2.

TABLE-US-00002 TABLE 2 Electron transporting V at 10 mA/ LT95 at 50 Appl. Ex. layer cm.sup.2, h mA/cm.sup.2, h Appl. Ex. 4 Compound 1 3.39 176 Appl. Ex. 5 Compound 2 3.55 147 Appl. Ex. 6 Compound 3 3.45 166 Comp. Appl. Comparative 5.59 5 Ex. 3 Compound 1

[0336] These results demonstrate that voltage and lifetime are improved in the case that the inventive Compounds are used instead of the Comparative Compounds 1 as the electron transporting material with LiF as electron injecting layer.

Application Example 7

[0337] A glass substrate with 130 nm-thick indium-tin-oxide (ITO) transparent electrode (manufactured by Geomatec Co., Ltd.) used as an anode was first treated with N2 plasma for 100 sec. This treatment also improved the hole-injection properties of the ITO. The cleaned substrate was mounted on a substrate holder and loaded into a vacuum chamber. Thereafter, the organic materials specified below were applied by vapor deposition to the ITO substrate at a rate of approx. 0.2-1 Å/sec at about 10.sup.−6-10.sup.−8 mbar. As a hole-injection layer, 10 nm-thick mixture of Compound HT and 3% by weight of Compound HI were applied. Then 80 nm-thick of Compound HT and 5 nm of Compound EB were applied as hole-transporting layer 1 and electron-blocking layer, respectively. Subsequently, a mixture of 1% by weight of an emitter Compound BD-1 and 99% by weight of host Compound BH-1 were applied to form a 20 nm-thick fluorescent-emitting layer. On the emitting layer, 5 nm-thick Compound HB was applied as an hole-blocking layer and 25 nm of mixture of 50% by weight of Compound 2 and lithium quinolate (Liq) as electron-transporting layer. Finally, 1 nm-thick Yb was deposited as an electron-injection layer and 80 nm-thick Al was then deposited as a cathode to complete the device. The device was sealed with a glass lid and a getter in an inert nitrogen atmosphere with less than 1 ppm of water and oxygen. To characterize the OLED, electroluminescence spectra were recorded at various currents and voltages. In addition, the current-voltage characteristic was measured in combination with the luminance to determine luminous efficiency and external quantum efficiency (EQE). Voltage and efficiency are reported at 10 mA/cm.sup.2. Lifetime of OLED device was measured as a decay of the luminance at constant current density of 50 mA/cm.sup.2 to 95% of its initial value. The device results are shown in Table 3.

TABLE-US-00003 TABLE 3 Electron transporting V at 10 LT95 at 50 Appl. Ex. layer mA/cm.sup.2, h mA/cm.sup.2, h Appl. Ex. 7 Compound 2:liq 3.2 142 (50%)

[0338] This result demonstrates that the inventive compounds can be applied in an electron transporting layer also comprising an alkali metal dopant.