Organic Light Emitting Device with Balanced Charge Injection

Solution Overview

Problem

Current organic light emitting devices face challenges in achieving improved driving voltage, efficiency, and lifetime.

Innovation Solution

The organic light emitting device incorporates a light emitting layer with a specific compound represented by Chemical Formula 1 and an electron transport region with a compound represented by Chemical Formula 2, which are designed to enhance hole and electron injection balance, leading to reduced voltage and improved efficiency and longevity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If conventional organic material layers are used in the light emitting device, then the device structure is simple, but the driving voltage is high and efficiency is low

Engineering Contradiction:

Improvedevice structureVSAvoiddriving voltage

Core Design Contradiction:

Device complexityVSUse of energy by moving object

Solution Approach 1:

The organic material layer is segmented into multiple functional sub-layers: hole injection layer, hole transport layer, light emitting layer, electron transport layer, and electron injection layer. Each sub-layer is optimized with specific compounds to perform its function efficiently, resulting in balanced charge injection and reduced driving voltage while maintaining structural organization.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent employs composite material structures where each layer contains specifically selected compounds with complementary properties. The hole transport layer uses compounds with high hole mobility, the electron transport layer uses compounds with high electron mobility, and the light emitting layer uses compounds optimized for radiative recombination. This composite approach enables efficient charge transport and reduced operating voltage.

Inventive Principle:

Principle #40Composite materials

2Device complexity

If conventional organic material layers are used in the light emitting device, then the device structure is simple, but the efficiency is low

Engineering Contradiction:

Improvedevice structureVSAvoidefficiency

Core Design Contradiction:

Device complexityVSProductivity

Solution Approach 1:

The organic material layer is segmented into multiple functional sub-layers: hole injection layer, hole transport layer, light emitting layer, electron transport layer, and electron injection layer. Each sub-layer is optimized with specific compounds to perform its function efficiently, resulting in balanced charge injection and reduced driving voltage while maintaining structural organization.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent employs composite material structures where each layer contains specifically selected compounds with complementary properties. The hole transport layer uses compounds with high hole mobility, the electron transport layer uses compounds with high electron mobility, and the light emitting layer uses compounds optimized for radiative recombination. This composite approach enables efficient charge transport and reduced operating voltage.

Inventive Principle:

Principle #40Composite materials

3Ease of manufacture

If conventional organic material layers are used in the light emitting device, then manufacturing is simple, but lifetime is short

Engineering Contradiction:

Improvemanufacturing simplicityVSAvoidlifetime

Core Design Contradiction:

Ease of manufactureVSDuration of action of stationary object

Solution Approach 1:

The organic material layer is segmented into multiple functional sub-layers: hole injection layer, hole transport layer, light emitting layer, electron transport layer, and electron injection layer. Each sub-layer is optimized with specific compounds to perform its function efficiently, resulting in balanced charge injection and reduced driving voltage while maintaining structural organization.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent incorporates stable compound structures with high thermal and chemical stability in each layer to prevent degradation. The hole transport and electron transport layers use compounds with high glass transition temperatures and stable molecular structures that resist degradation under operating conditions, thereby extending device lifetime before manufacture.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

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 device exhibits excellent driving voltage, efficiency, and extended lifetime due to the balanced injection of holes and electrons, as demonstrated by the synthesis and application of these compounds in the organic light emitting device structure.

Implementation Method 1

an organic light emitting phenomenon refers to a phenomenon where electrical energy is converted into light energy by using an organic material

Methodology Applied

Scientific EffectElectroluminescence: Electroluminescence

Data Source

PatentUS11211563B2Organic light emitting device

Publication Date: 2021.12.28 LG CHEM LTD

AI summary

The present invention relates to an organic light emitting device comprising a light emitting layer including a compound represented by Chemical Formula 1 and an electron transport region including a compound represented by Chemical Formula 2, and having improved driving voltage, efficiency, and lifetime.