Organic light emitting display device

Patent metadata

Field	Value
Publication number	US-10056571-B2
Application number	US-201615163462-A
Country	US
Kind code	B2
Filing date	May 24, 2016
Priority date	Nov 26, 2015
Publication date	Aug 21, 2018
Grant date	Aug 21, 2018

Abstract

An organic light emitting display device includes: a first light emitting unit including a first light emitting layer; and a second light emitting unit on the first light emitting unit including a second light emitting layer. The first light emitting layer includes at least one dopant and at least two hosts. The at least two hosts are different from each other in electron mobility and hole mobility.

First claim

What is claimed is:

1. An organic light emitting display device comprising:
a first light emitting unit including a first light emitting layer; and
a second light emitting unit on the first light emitting unit including a second light emitting layer,
wherein the first light emitting unit and the second light emitting unit are between an anode and a cathode,
wherein the first light emitting layer includes at least one dopant and at least two hosts,
wherein the at least two hosts are different from each other in electron mobility and hole mobility,
wherein the at least two hosts comprise a first host including a first hole-type host and a first electron-type host, and a second host including a second electron-type host,
wherein an electron mobility of the first hole-type host is higher than an electron mobility of the first electron-type host, and a hole mobility of the first hole-type host is higher than a hole mobility of the first electron-type host, and
wherein absolute values of LUMO (lowest unoccupied molecular orbital) energy levels of the first host and second host are same and absolute values of HOMO (highest occupied molecular orbital) energy levels of the first host and second host are same.

2. The organic light emitting display device according to claim 1 , wherein an electron mobility of the first hole-type host is higher than a hole mobility of the first hole-type host.

3. The organic light emitting display device according to claim 1 , wherein an electron mobility of the first electron-type host and an electron mobility of the second electron-type host are higher than a hole mobility of the first electron-type host and a hole mobility of the second electron-type host.

4. The organic light emitting display device according to claim 1 , wherein a volume ratio of the first hole-type host and the first electron-type host is 5:5.

5. The organic light emitting display device according to claim 1 , wherein absolute values of the LUMO energy levels of the first host and the second host are in the range of from 3.0 eV to 6.0 eV, and
wherein absolute values of the HOMO energy levels of the first host and the second host are in the range of from 1.0 eV to 3.0 eV.

6. The organic light emitting display device according to claim 1 , wherein the first light emitting unit further includes a hole transfer layer and an electron transfer layer, and
wherein the first host is adjacent to the hole transfer layer and the second host is adjacent to the electron transfer layer.

7. The organic light emitting display device according to claim 1 , further comprising:
a third light emitting unit on the second light emitting unit including a third light emitting layer,
wherein the third light emitting layer includes at least two hosts which are different from each other in electron mobility and hole mobility.

8. The organic light emitting display device according to claim 7 , wherein the third light emitting unit further includes a hole transfer layer and an electron transfer layer, and
wherein the first host is adjacent to the hole transfer layer and the second host is adjacent to the electron transfer layer.

9. An organic light emitting display device comprising:
a plurality of light emitting units between an anode and a cathode including a plurality of light emitting layers,
wherein at least one of the plurality of light emitting layers includes at least one dopant and at least two hosts, and the at least two hosts include a first host including a first hole-type host and a first electron-type host, and a second host including a second electron-type host,
wherein an electron mobility of the first hole-type host is higher than an electron mobility of the first electron-type host, and a hole mobility of the first hole-type host is higher than a hole mobility of the first electron-type host,
wherein an absolute value of a LUMO (lowest unoccupied molecular orbital) energy level of the first host is same as an absolute value of a LUMO energy level of the second host, and
wherein an absolute value of a HOMO (highest occupied molecular orbital) energy level of the first host is same as an absolute value of a HOMO energy level of the second host.

10. The organic light emitting display device according to claim 9 , wherein a volume ratio of the first hole-type host and the first electron-type host is 5:5.

11. The organic light emitting display device according to claim 9 , wherein the absolute values of the LUMO energy levels of the first host and the second host are in the range of from 3.0 eV to 6.0 eV, and the absolute values of the HOMO energy levels of the first host and the second host are in the range of from 1.0 eV to 3.0 eV.

12. The organic light emitting display device according to claim 9 , wherein the plurality of light emitting units further includes a hole transfer layer and an electron transfer layer, and
wherein the first host is adjacent to the hole transfer layer and the second host is adjacent to the electron transfer layer.

13. The organic light emitting display device according to claim 9 , wherein at least one among the plurality of light emitting layers includes a blue light emitting layer, and
wherein the blue light emitting layer includes the first host and the second host.

14. An organic light emitting display device comprising:
a plurality of light emitting units between an anode and a cathode including a plurality of light emitting layers,
wherein at least one among the plurality of light emitting layers includes two areas, and a first area among the two areas includes a mixed host and a second area includes a single host,
wherein the mixed host includes a first hole-type host and a first electron-type host, and the single host includes a second electron-type host,
wherein an electron mobility of the first hole-type host is higher than an electron mobility of the first electron-type host, and a hole mobility of the first hole-type host is higher than a hole mobility of the first electron-type host,
wherein an absolute value of a LUMO (lowest unoccupied molecular orbital) energy level of the mixed host is same as an absolute value of a LUMO energy level of the single host, and
wherein an absolute value of a HOMO (highest occupied molecular orbital) energy level of the mixed host is same as an absolute value of a HOMO energy level of the single host.

15. The organic light emitting display device according to claim 14 , wherein an electron mobility of the first hole-type host is higher than a hole mobility of the first hole-type host.

16. The organic light emitting display device according to claim 14 , wherein an electron mobility of the first electron-type host and an electron mobility of the second electron-type host are higher than a hole mobility of the first electron-type host and a hole mobility of the second electron-type host.

17. The organic light emitting display device according to claim 14 , wherein a volume ratio of the first hole-type host and the first electron-type host is 5:5.

18. The organic light emitting display device according to claim 14 , wherein the plurality of light emitting units further includes a hole transfer layer and an electron transfer layer, and
wherein the mixed host is adjacent to the hole transfer layer and the single host is adjacent to the electron transfer layer.

19. The organic light emitting display device according to claim 14 , wherein the light emitting layer including at least two areas includes a blue light emitting layer.

20. An or

Assignees

• Lg Display Co Ltd

Inventors

• Han Yoondeok
• Choi Hongseok
• Ahn Soyeon
• Park Jungsoo
• LEE Yosub

Classifications

• H01L27/3258

  Electricity · mapped topic

• H01L27/3262

  Electricity · mapped topic

• H01L51/504 Primary

  Electricity · mapped topic

• H01L2251/5384

  Electricity · mapped topic

• H01L51/5004

  Electricity · mapped topic