OLED Compounds with Spacer Groups for Color Tuning and Stability

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing organic light emitting diode (OLED) technologies face challenges with the stability and performance of devices when using functional groups like TMS and CF3 side chains, which can adversely affect device lifetime and color tuning.

Innovation Solution

Development of fluorescent compounds with substituents such as bis(trimethylsilyl)methyl (BTMSM) and Si—F bonds, where these groups are separated from the aromatic ring by at least one carbon atom, enhancing stability and tuning capabilities.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If TMS or CF3 side chains are used in OLED compounds, then color tuning capability is improved, but device lifetime and stability deteriorate

Engineering Contradiction:

Improvecolor tuning capabilityVSAvoiddevice lifetime

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The patent introduces a spacer group (such as -CH2-, -O-, -S-, -NR-, or aromatic ring) as an intermediary between the TMS/CF3 side chain and the aromatic ring. This spacer acts as a mediator that allows the color-tuning function of the side chain to be maintained while preventing the direct adverse interaction between the side chain and the aromatic ring that causes device degradation, thereby resolving the contradiction between color tuning capability and device lifetime

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent segments the side chain structure by inserting a spacer group between the functional group (TMS/CF3) and the aromatic ring core. This segmentation separates the color-tuning function from the stability-critical region, allowing independent optimization of both properties - the side chain maintains its color-tuning capability while the spacer protects the aromatic ring from degradation

Inventive Principle:

Principle #1Segmentation

2Adaptability or versatility

If TMS or CF3 side chains are attached directly to aromatic rings, then molecular properties are modified, but device performance and stability worsen

Engineering Contradiction:

Improvemolecular property tuningVSAvoidadverse effects on device performance

Core Design Contradiction:

Adaptability or versatilityVSObject-affected harmful factors

Solution Approach 1:

The spacer group serves as a protective intermediary that transmits the electronic effects of TMS/CF3 for property tuning while blocking direct harmful interactions with the aromatic ring, thus achieving molecular property modification without adverse device performance effects

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The spacer group provides beforehand cushioning by being positioned between the TMS/CF3 side chain and the aromatic ring before any harmful interaction can occur. This pre-protective structure prevents degradation pathways while allowing the side chain to exert its desired electronic effects on the molecule

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 new compounds improve OLED device stability and emission properties, preventing adverse effects on lifetime and allowing for effective color tuning, thereby enhancing overall performance.

Implementation Method 1

the first compound is capable of functioning as a fluorescent emitter in an organic light emitting device

Methodology Applied

Scientific EffectFluorescence: Fluorescence

Implementation Method 2

OLEDs make use of thin organic films that emit light when voltage is applied across the device

Methodology Applied

Scientific EffectElectroluminescence: Electroluminescence

Data Source

PatentUS9711730B2Organic electroluminescent materials and devices

Publication Date: 2017.07.18 UNIVERSAL DISPLAY CORP

AI summary

This invention discloses novel light-emitting materials. These materials comprise a side chain which contains at least two Si or Ge atoms, such as bis(trimethylsilyl)methyl, or a side chain that includes Si—F bond, or a side chain that includes a fluorine-containing alkyl chain. This new side chain could fine tune emission color, reduce the stacking of the light-emitting materials, maintain good lifetime, and result in high PLQY.