WHITE ORGANIC LIGHT-EMITTING DEVICE
The present invention relates to white organic light-emitting devices having separate stacked blue/green phosphorescent and red phosphorescent layers. The white organic light-emitting devices emit the desired natural white color and show a reduced power consumption, superior current efficiency, efficacy, external quantum efficiency (EQE) and/or lifetime. In particular, the efficiency of the white organic light emitting device is improved and at the same time the lifetime of the white organic light emitting device is increased.
1 . A white organic light-emitting device comprising
(a) an anode,
(i) a cathode,
(e) an emitting layer between the anode and cathode, comprising
(e1) a first light-emitting layer and
(e2) a second light-emitting layer, wherein
the first light-emitting layer is in direct contact with the second light-emitting layer,
the first light-emitting layer comprises a phosphorescent red emitter and a first host compound, and
the second light-emitting layer comprises a phosphorescent blue emitter, a phosphorescent green emitter and a second host compound.
2 . The organic light-emitting device according to claim 1 , wherein the first light-emitting layer (e1) is disposed between the anode (a) and the second light-emitting layer (e2).
3 . The organic light-emitting device according to claim 1 , comprising in this order:
(a) an anode,
(b) optionally a hole injection layer,
(c) a hole transport layer,
(d) exciton blocking layer
(e) an emitting layer, comprising
(e1) a first light-emitting layer,
(e2) a second light-emitting layer,
(f) a hole/exciton blocking layer
(g) an electron transport layer,
(h) optionally an electron injection layer, and
(i) a cathode.
4 . The organic light-emitting device according to claim 1 , wherein the phosphorescent red emitter is a compound of a formula selected from the group consisting of:
5 . The organic light-emitting device according to claim 4 , wherein the phosphorescent red emitter is a compound of a formula selected from the group consisting of:
6 . The organic light-emitting device according to claim 1 , wherein the first host compound is a compound selected from the group consisting of:
4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (FH-1), and 4,4′,4″-tris(N-carbazolyl)-triphenylamine (FH-2).
7 . The organic light-emitting device according to claim 6 , wherein the first host compound is formula
or formula
8 . The organic light-emitting device according to claim 1 , wherein the phosphorescent blue emitter is a compound of a formula selected from the group consisting of:
9 . The organic light-emitting device according to claim 1 , wherein the phosphorescent blue emitter is a compound of a formula selected from the group consisting of:
10 . The organic light-emitting device according to claim 1 , wherein the phosphorescent green emitter is a compound of a formula selected from the group consisting of:
11 . The organic light-emitting device according to claim 10 , wherein the phosphorescent green emitter is a compound of a formula selected from the group consisting of:
12 . The organic light-emitting device according to claim 1 , wherein the second host compound is a compound of a formula selected from the group consisting of:
wherein T is O, or S.
13 . The organic light-emitting device according to claim 1 , wherein the second host compound is a compound of a formula selected from the group consisting of:
14 . The organic light-emitting device according to claim 3 , wherein the hole transport layer comprises a compound of formula
or formula
15 . The organic light-emitting device according to claim 3 , wherein the electron transport layer comprises:
16 . The organic light-emitting device according to claim 1 , comprising in this order:
(a) an anode,
(b) (sulfonated poly(thiophene-3-[2[(2-methoxyethoxy)ethoxy]-2,5-diyl) (hole injection layer),
(c) MoO 3 /HTM-1 (hole transport layer),
(d) HTM-1 (exciton blocking layer)
(e) emitting layer, comprising:
(e1) RE-2/HTM-1 (first light-emitting layer),
(e2) BE-1/GE-1/SH-2 (second light-emitting layer),
(f) SH-2 (exciton blocking layer)
(g) ETM-1/Liq (electron transport layer),
(h) KF (electron injection layer), and
(i) a cathode;
or
comprising in this order:
(a) an anode,
(b) (sulfonated poly(thiophene-3-[2[(2-methoxyethoxy)ethoxy]-2,5-diyl) (hole injection layer),
(c) MoO 3 /HTM-2 (hole transport layer),
(d) HTM-2 (exciton blocking layer),
(e) emitting layer, comprising:
(e1) RE-2/HTM-2 (first light-emitting layer),
(e2) BE-1/GE-1/SH-2 (second light-emitting layer),
(f) SH-2 (exciton blocking layer)
(g) ETM-1/Liq (electron transport layer), and
h) KF (electron injection layer), and
(i) Al (cathode);
or
comprising in this order:
(a) an anode,
(b) (sulfonated poly(thiophene-3-[2[(2-methoxyethoxy)ethoxy]-2,5-diyl) (hole injection layer),
(c) MoO 3 /HTM-1 (Ir(DPBIC) 3 ) (hole transport layer),
(d) HTM-1 (exciton blocking layer)
(e) emitting layer, comprising:
(e1) RE-1/HTM-1 (first light-emitting layer),
(e2) BE-1/GE-1/SH-1 (second light-emitting layer),
(f) SH-1 (exciton blocking layer)
(g) ETM-1/Liq (electron transport layer), and
(h) a cathode;
or
comprising in this order:
(a) an anode,
(b) (sulfonated poly(thiophene-3-[2[(2-methoxyethoxy)ethoxy]-2,5-diyl) (hole injection layer),
(c) MoO 3 /HTM-2 (hole transport layer),
(d) HTM-2 (exciton blocking layer)
(e) emitting layer, comprising:
(e1) RE-1/HTM-2 (first light-emitting layer),
(e2) BE-1/GE-1/SH-1 (second light-emitting layer),
(f) SH-1 (exciton blocking layer)
(g) ETM-1/Liq (electron transport layer), and
(h) a cathode.
17 . An emitting layer (e), comprising
(e1) a first light-emitting layer and
(e2) a second light-emitting layer, wherein
the first light-emitting layer is in direct contact with the second light-emitting layer,
the first light-emitting layer comprises a phosphorescent red emitter and a first host compound, and
the second light-emitting layer comprises a phosphorescent blue emitter, a phosphorescent green emitter and a second host compound.
18 . An apparatus selected from the group consisting of: a stationary visual display unit; an illumination unit; a keyboard; an item of clothing; furniture; and wallpaper, comprising the emitting layer of claim 17 .
19 . A method of generating white light, comprising supplying an electric current to the emitting layer (e) of the apparatus according to claim 18 thereby generating white light.
20 . An apparatus selected from the group consisting of: a stationary visual display unit; an illumination unit; a keyboard; an item of clothing; furniture; and wallpaper, comprising the organic electronic device according to claim 1 .