Pyrene Derivative for OLED Blue Light Purity and Efficiency

Solution Overview

Problem

Existing organic electroluminescent elements face issues with blue color purity and luminous efficiency, as well as color change due to drive deterioration, particularly when using compounds with heterocyclic rings condensed on a pyrene skeleton.

Innovation Solution

Incorporating a pyrene derivative with a specific structure, where the compound contains a linking group represented by general formula (1), which includes oxygen or sulfur atoms, and specific substitution groups, to enhance blue color purity and luminous efficiency, and reduce color change due to drive deterioration.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If a compound with a heterocyclic ring containing a nitrogen atom is condensed in the major axis direction of a pyrene skeleton, then luminous efficiency and longevity are improved, but blue color purity is insufficient

Engineering Contradiction:

Improveluminous efficiencyVSAvoidblue color purity

Core Design Contradiction:

Loss of energyVSIllumination intensity

Solution Approach 1:

The patent applies local quality by introducing specific substitution groups (fluorine, alkyl, silyl, or amino groups) at predetermined positions on the pyrene skeleton. This localized modification at specific molecular sites adjusts the HOMO-LUMO energy levels and light emission characteristics, achieving both high luminous efficiency and excellent blue color purity simultaneously

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent employs parameter changes by modifying the chemical structure parameters of the pyrene derivative - specifically introducing heterocyclic rings with nitrogen, oxygen, or sulfur atoms at defined positions and adding substitution groups. These structural parameter changes optimize the energy levels and emission properties to resolve the contradiction between luminous efficiency and color purity

Inventive Principle:

Principle #35Parameter changes

2Illumination intensity

If a compound with favorable blue color purity is used, then blue color purity is improved, but color change due to drive deterioration occurs

Engineering Contradiction:

Improveblue color purityVSAvoidcolor stability

Core Design Contradiction:

Illumination intensityVSStability of the object's composition

Solution Approach 1:

The patent uses composite materials by creating a complex molecular structure that combines the pyrene skeleton, heterocyclic rings, and multiple substitution groups into a single integrated compound. This composite structure achieves both excellent blue color purity and resistance to color change during operation

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The patent applies local quality by introducing specific substitution groups (fluorine, alkyl, silyl, or amino groups) at predetermined positions on the pyrene skeleton. This localized modification at specific molecular sites adjusts the HOMO-LUMO energy levels and light emission characteristics, achieving both high luminous efficiency and excellent blue color purity simultaneously

Inventive Principle:

Principle #3Local quality

3Ease of manufacture

If conventional pyrene skeleton compounds are used, then manufacturing simplicity is maintained, but luminous efficiency and color purity are insufficient

Engineering Contradiction:

Improvemanufacturing simplicityVSAvoidluminous efficiency

Core Design Contradiction:

Ease of manufactureVSLoss of energy

Solution Approach 1:

The patent employs parameter changes by modifying the chemical structure parameters of the pyrene derivative - specifically introducing heterocyclic rings with nitrogen, oxygen, or sulfur atoms at defined positions and adding substitution groups. These structural parameter changes optimize the energy levels and emission properties to resolve the contradiction between luminous efficiency and color purity

Inventive Principle:

Principle #35Parameter changes

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 electroluminescent element achieves high luminous efficiency, excellent blue color purity, and low color change over time, with improved stability and performance in light emitting devices.

Implementation Method 1

an electron injected from a cathode and an electron hole injected from an anode are rebonded in the organic layer, and the energy of a generated exciton is used for light emission

Methodology Applied

Scientific EffectElectroluminescence: Electroluminescence

Data Source

PatentUS10297760B2Organic electroluminescent element, compound and material for organic electroluminescent element, used in the same, and light emitting device, display device and illumination device, using the element

Publication Date: 2019.05.21 UDC IRELAND

AI summary

An organic electroluminescent element comprising a substrate, a pair of electrodes including an anode and a cathode, disposed on the substrate, and at least one organic layer which is arranged between the electrodes and which includes a light emitting layer, wherein the organic layer contains a compound represented by general formula (1) in at least one layer. The organic electroluminescent element has a high luminous efficiency, excellent blue color purity, and little chromaticity change due to drive deterioration. (In the formula, the two Xs either both represent an O atom or both represent an S atom, and R1-R10 each independently represents a hydrogen atom or a substituent group).