Highly efficient OLED devices with very short decay times

US10347851B2 · kind B2 · utility

Assignee

• UDC IRELAND LIMITED · IE

Inventors

• Christian Lennartz · Dublin, IE
• Stefan Metz · Dublin, IE
• Korinna Dormann · Bad Dürkheim, DE
• Gerhard Wagenblast · Wachenheim, DE
• Ute Heinemeyer · Neustadt, DE
• Hannah Stephanie Mangold · Ludwigshafen am Rhein, DE
• Minlu Zhang · Bad Dürkheim, DE
• Thomas Wesley Holcombe · Schifferstadt, DE

Key dates

• Filing date: Dec 17, 2014
• Grant date: Jul 9, 2019
• Expiry date: Dec 17, 2034

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02E10/549
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

The present invention relates to organic light-emitting devices comprising (a) an anode, (i) a cathode, and (e) an emitting layer between the anode and cathode, comprising 2 to 40% by weight of a luminescent organometallic complex X having a difference of the singlet energy (ES1(X)) and the triplet energy (ET1(X)) of smaller than 0.2 eV [Δ (ES1(X))−(ET1(X))<0.2 eV], 0.05 to 5.0% by weight of a fluorescent emitter Y and 55 to 97.95% by weight of a host compound(s), wherein the amount of the organometallic complex X, the fluorescent emitter Y and the host compound(s) adds up to a total of 100% by weight and the singlet energy of the luminescent organometallic complex X (ES1(X)) is greater than the singlet energy of the fluorescent emitter Y (ES1(Y)) [(ES1(X))>ES1(Y)]. By doping, for example, an emitting layer containing a luminescent organometallic complex having a small S1-T1 splitting, with a fluorescent emitter the emission decay time can significantly be shortened without sacrificing external quantum efficiency (EQE) because of very efficient energy transfer.