Light-emitting layer, light-emitting device and light-emitting apparatus

Patent metadata

Field	Value
Publication number	US-12575321-B2
Application number	US-202217898127-A
Country	US
Kind code	B2
Filing date	Aug 29, 2022
Priority date	Jun 30, 2022
Publication date	Mar 10, 2026
Grant date	Mar 10, 2026

Abstract

A light-emitting layer, a light-emitting device and a light-emitting apparatus are provided. The light-emitting layer includes a thermally activated delayed fluorescence (TADF) material, a phosphorescent material, a multiple resonance fluorescent material and a host material.

First claim

What is claimed is:

1 . A light-emitting layer, comprising:
a thermally activated delayed fluorescence (TADF) material, a phosphorescent material, a multiple resonance fluorescent material and a host material, wherein: a difference between HOMO energy levels of the host material and the TADF material is less than 0.1 eV, and a difference between LUMO energy levels of the host material and the TADF material is less than 0.1 eV; a difference between HOMO energy levels of the TADF material and the phosphorescent material is less than 0.1 eV, and a difference between LUMO energy levels of the TADF material and the phosphorescent material is less than 0.1 eV; and a difference between HOMO energy levels of the phosphorescent material and the multiple resonance fluorescent material is less than 0.1 eV, and a difference between LUMO energy levels of the phosphorescent material and the multiple resonance fluorescent material is less than 0.1 eV.

2 . The light-emitting layer according to claim 1 , wherein:
a singlet energy level of the host material is greater than a singlet energy level of the TADF material, and a triplet energy level of the host material is greater than a triplet energy level of the TADF material; the singlet energy level of the TADF material is greater than a singlet energy level of the phosphorescent material, and the triplet energy level of the TADF material is greater than a triplet energy level of the phosphorescent material; and the singlet energy level of the phosphorescent material is greater than a singlet energy level of the multiple resonance fluorescent material, and the triplet energy level of the phosphorescent material is greater than a triplet energy level of the multiple resonance fluorescent material; or highest-occupied molecular orbital (HOMO) energy levels of the host material, the TADF material, the phosphorescent material and the multiple resonance fluorescent material gradually increase; and lowest-unoccupied molecular orbital (LUMO) energy levels of the host material, the TADF material, the phosphorescent material and the multiple resonance fluorescent material gradually decrease.

3 . The light-emitting layer according to claim 1 , wherein:
a difference between a HOMO energy level of the TADF material and a LUMO energy level of the phosphorescent material is greater than a triplet energy level of the phosphorescent material by more than 0.2 eV; and a difference between a LUMO energy level of the TADF material and a HOMO energy level of the phosphorescent material is greater than a triplet energy level of the phosphorescent material by more than 0.2 eV.

4 . The light-emitting layer according to claim 1 , wherein:
a difference between a HOMO energy level of the TADF material and a LUMO energy level of the multiple resonance fluorescent material is greater than a singlet energy level of the multiple resonance fluorescent material by more than 0.2 eV; and a difference between a LUMO energy level of the TADF material and a HOMO energy level of the multiple resonance fluorescent material is greater than the singlet energy level of the multiple resonance fluorescent material by more than 0.2 eV.

5 . The light-emitting layer according to claim 1 , wherein:
a luminescence peak of the TADF material is red-shifted by less than 0.3 eV with respect to a peak of a minimum absorption band of the phosphorescent material; a luminescence peak of the phosphorescent material is red-shifted by less than 0.3 eV with respect to an absorption peak in visible light band of the multiple resonance fluorescent material; and the luminescence peak of the TADF material is red-shifted by less than 0.3 eV with respect to the absorption peak in visible light band of the multiple resonance fluorescent material.

6 . The light-emitting layer according to claim 1 , wherein:
the TADF material has a structure of Formula A:

wherein in the Formula A, R 1 -R 6 are independently selected from hydrogen, deuterium, halogen, cyano, alkyl, substituted or unsubstituted aryl, and substituted or unsubstituted heteroaryl; and
the halogen in the Formula A is selected from F, the alkyl is selected from methyl and CD 3 , the aryl is selected from phenyl, and the heteroaryl is selected from following formulas:

7 . The light-emitting layer according to claim 6 , wherein:
the TADF material is selected from one or more of structures of Formulas A-1 to A-20:

8 . The light-emitting layer according to claim 1 , wherein:
the phosphorescent material has a structure of Formula B:

wherein in the Formula B, R 7 -R 9 are independently selected from substituted or unsubstituted aryl, and substituted or unsubstituted heteroaryl; and
the R 7 -R 9 are independently selected from following groups:

9 . The light-emitting layer according to claim 8 , wherein:
the phosphorescent material is selected from one or more of structures of Formulas B-1 to B-14:

10 . The light-emitting layer according to claim 1 , wherein:
the multiple resonance fluorescent material has a structure of Formula C:

wherein in the Formula C, R 10 -R 16 are independently selected from hydrogen, deuterium, halogen, —B═, substituted or unsubstituted alkyl, substituted or unsubstituted aryl, and substituted or unsubstituted heteroaryl; and
unsubstituted alkyl group in the Formula C is selected from methyl and butyl, substituted alkyl group is selected from —Si(CH 3 ) 3 , aryl group is selected from phenyl, and heteroaryl is selected from following structures:

11 . The light-emitting layer according to claim 10 , wherein:
the multiple resonance fluorescent material is selected from one of structures of Formula C-1 to Formula C-19:

12 . The light-emitting layer according to cl

Assignees

• Hubei Yangtze Ind Innovation Center Of Advanced Display Co Ltd

Inventors

• Hua Wanming
• Niu Jinghua
• Lin Yafei
• Wang Jianyun
• Zhang Shaoli

Classifications

• C09K2211/185

  of the platinum group, i.e. Os, Ir, Pt, Ru, Rh or Pd · CPC title

• C09K2211/1033

  with oxygen · CPC title

• C09K2211/1029

  containing one nitrogen atom as the heteroatom · CPC title

• C09K2211/1018

  Heterocyclic compounds · CPC title

• C09K11/06 Primary

  containing organic luminescent materials · CPC title