Organic Light Emitting Compounds for Low Voltage Displays

Solution Overview

Problem

Phosphorescent materials for organic light emitting devices face challenges with instability and high driving voltage, leading to low power efficiency and short device life, despite their theoretical potential for high luminous efficiency.

Innovation Solution

The development of organic light emitting devices incorporating specific compounds represented by Formulas A and B, which form an organic layer with a light emitting layer, hole transport layer, and electron transport layer, enabling low driving voltage, high efficiency, and extended device life.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If phosphorescent materials are used in organic light emitting devices, then luminous efficiency is improved, but driving voltage increases and device life decreases

Engineering Contradiction:

Improveluminous efficiencyVSAvoiddevice life

Core Design Contradiction:

Use of energy by moving objectVSReliability

Solution Approach 1:

The patent employs a host/dopant composite material system where phosphorescent dopant compounds are incorporated into a host matrix. This composite structure allows the phosphorescent materials to achieve high luminous efficiency while the host material provides structural stability and reduces degradation, thereby extending device life despite the use of phosphorescent materials.

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The patent modifies the chemical structure parameters of phosphorescent dopant compounds by introducing specific substituents and functional groups. These parameter changes optimize the phosphorescent materials' properties to reduce operating voltage and improve stability, resolving the contradiction between high luminous efficiency and long device life.

Inventive Principle:

Principle #35Parameter changes

2Use of energy by moving object

If phosphorescent materials are used in organic light emitting devices, then luminous efficiency is improved, but driving voltage increases

Engineering Contradiction:

Improveluminous efficiencyVSAvoiddriving voltage

Core Design Contradiction:

Use of energy by moving objectVSPower

Solution Approach 1:

The patent modifies the chemical structure parameters of phosphorescent dopant compounds by introducing specific substituents and functional groups. These parameter changes optimize the phosphorescent materials' properties to reduce operating voltage and improve stability, resolving the contradiction between high luminous efficiency and long device life.

Inventive Principle:

Principle #35Parameter changes

3Device complexity

If a single light emitting material is used, then device structure is simple, but intermolecular interaction causes low color purity and luminescence quenching reduces efficiency

Engineering Contradiction:

Improvematerial system complexityVSAvoidluminous efficiency

Core Design Contradiction:

Device complexityVSUse of energy by moving object

Solution Approach 1:

The patent employs a host/dopant composite material system where phosphorescent dopant compounds are incorporated into a host matrix. This composite structure allows the phosphorescent materials to achieve high luminous efficiency while the host material provides structural stability and reduces degradation, thereby extending device life despite the use of phosphorescent materials.

Inventive Principle:

Principle #40Composite materials

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The organic light emitting devices exhibit low driving voltage, high efficiency, and improved life characteristics, making them suitable for various industrial applications such as displays and lighting systems.

Implementation Method 1

Organic light emitting diodes are self-luminous devices

Methodology Applied

Scientific EffectElectroluminescence: Electroluminescence

Implementation Method 2

extensive research is being conducted to develop phosphorescent materials, which are known to achieve improved luminous efficiency theoretically by a factor of up to 4 compared to fluorescent materials, based on the luminescence mechanism of organic light emitting layers

Methodology Applied

Scientific EffectPhosphorescence: Phosphorescence

Data Source

PatentUS11476426B2Organic light emitting compounds and organic light emitting devices including the same

Publication Date: 2022.10.18 SFC CO LTD

AI summary

Disclosed is an organic light emitting device including a first electrode, a second electrode opposite to the first electrode, and at least one organic layer interposed between the first and second electrodes. The organic layer includes first and second compounds represented by Formulae A and B, respectively:The organic light emitting device exhibits low driving voltage, high efficiency, and long life. Due to these advantages, the organic light emitting device is useful in a variety of industrial applications, including displays and lighting systems.