Organic electroluminescent display panel

Patent metadata

Field	Value
Publication number	US-9755177-B2
Application number	US-201415025931-A
Country	US
Kind code	B2
Filing date	Oct 8, 2014
Priority date	Oct 9, 2013
Publication date	Sep 5, 2017
Grant date	Sep 5, 2017

Abstract

The organic EL display panel includes: an active matrix substrate including a thin-film transistor; and an organic EL element disposed on the active matrix substrate, the organic EL element including, in the order from the active matrix substrate side, a cathode electrically connected to the thin-film transistor, a first charge conversion layer in contact with the cathode, a first hole injection layer, a first hole transport layer, a first light-emitting layer, a first electron transport layer, a first electron injection layer, a second charge conversion layer, and an anode in contact with the second charge conversion layer, the first charge conversion layer designed to inject electrons into the cathode and emit holes to the first light-emitting layer side, the second charge conversion layer designed to inject holes into the anode and emit electrons to the first light-emitting layer side.

First claim

The invention claimed is:

1. An organic electroluminescent display panel comprising:
an active matrix substrate including a thin-film transistor; and
an organic electroluminescent element disposed on the active matrix substrate,
the organic electroluminescent element including, in an order from an active matrix substrate side:
a cathode electrically connected to the thin-film transistor,
a first charge conversion layer in contact with the cathode,
a first hole injection layer,
a first hole transport layer,
a first light-emitting layer,
a first electron transport layer,
a first electron injection layer,
a laminate,
a second charge conversion layer, and
an anode in contact with the second charge conversion layer,
the first charge conversion layer defined to inject electrons into the cathode and emit holes to a first light-emitting layer side,
the second charge conversion layer defined to inject holes into the anode and emit electrons to the first light-emitting layer side,
the laminate including one or more charge-generating layers and one or more light-emitting layers alternately in order from a first electron injection layer side.

2. The organic electroluminescent display panel according to claim 1 , wherein
the first charge conversion layer includes a first charge-generating layer, and
the second charge conversion layer includes a second charge-generating layer.

3. The organic electroluminescent display panel according to claim 2 , wherein the first charge conversion layer includes a layer having electron injection ability and the first charge-generating layer in the order from the active matrix substrate side.

4. The organic electroluminescent display panel according to claim 2 , wherein the second charge conversion layer includes the second charge-generating layer and a layer having hole injection ability in the order from the active matrix substrate side.

5. The organic electroluminescent display panel according to claim 2 , wherein
the first charge conversion layer includes a layer having electron injection ability and the first charge-generating layer in the order from the active matrix substrate side, and
the second charge conversion layer includes the second charge-generating layer and a layer having hole injection ability in the order from the active matrix substrate side.

6. The organic electroluminescent display panel according to claim 3 , wherein the layer having electron injection ability contains an alkali metal or an alkaline earth metal.

7. The organic electroluminescent display panel according to claim 2 , wherein at least one of the first and second charge-generating layers is made of a p-type oxide.

8. The organic electroluminescent display panel according to claim 1 , wherein the laminate includes the charge-generating layer, a second hole injection layer, a second hole transport layer, a second light-emitting layer, a second electron transport layer, and a second electron injection layer in the order from the first electron injection layer side.

9. The organic electroluminescent display panel according to claim 1 , wherein the organic electroluminescent display panel is a top emission organic electroluminescent display panel which emits light from an anode side.

10. The organic electroluminescent display panel according to claim 1 , wherein the organic electroluminescent display panel is a bottom emission organic electroluminescent display panel which emits light from a cathode side.

11. The organic electroluminescent display panel according to claim 1 , wherein the thin-film transistor includes a semiconductor layer containing an oxide semiconductor.

12. The organic electroluminescent display panel according to claim 5 , wherein the layer having electron injection ability contains an alkali metal or an alkaline earth metal.

Assignees

• Sharp Kk

Inventors

• Niboshi Manabu
• Isomura Yoshiyuki
• Tsukamoto Yuto
• Kikuchi Katsuhiro
• Uchida Hideki
• Endo Ayataka
• ITO Asae

Classifications

• H01L2251/303

  Electricity · mapped topic

• H01L27/3209

  Electricity · mapped topic

• H01L51/50

  Electricity · mapped topic

• H01L2251/5307

  Electricity · mapped topic

• H01L2251/301

  Electricity · mapped topic