Pixel Defining Layer Lyophobic Stability via Fluorinated Monolayer

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional methods for maintaining lyophobic performance of pixel defining layers in display substrates, such as those used in organic electroluminescent light-emitting diodes, are ineffective over time due to the transient nature of plasma treatments, which can be compromised by long-term processes or high-temperature annealing.

Innovation Solution

A method involving the formation of a basic pattern of inorganic material on a substrate, followed by a self-assembled fluorinated monomolecular layer using fluorooctyl trichlorosilane, which forms a covalent bond and maintains lyophobic performance without being affected by cleaning or annealing processes.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If plasma treatment is used to maintain lyophobic performance of pixel defining layer, then initial lyophobic performance is improved, but performance degrades over time due to transient nature

Engineering Contradiction:
Improvelyophobic performance stabilityVSAvoidduration of lyophobic performance
Core Design Contradiction:
ReliabilityVSDuration of action of stationary object

Solution Approach 1:

The invention changes the chemical composition of the pixel defining layer by incorporating fluorinated compounds (specifically fluorinated cyclic carbonate and fluorinated cyclic carboxylate) to fundamentally alter the surface energy parameters. This chemical modification maintains lyophobic performance (contact angle >90°) stably over time, resolving the transient degradation issue of plasma treatment by establishing a permanent chemical property rather than a temporary physical state.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The invention creates a composite pixel defining layer by combining organic resin base materials with specific fluorinated cyclic carbonate and fluorinated cyclic carboxylate compounds. This composite structure integrates the lyophobic properties of fluorinated compounds into the matrix of the pixel defining layer, ensuring long-term stability of contact angle and lyophobic performance through the synergistic effect of the composite material system.

Inventive Principle:
Principle #40Composite materials

2Reliability

If conventional pixel defining layer materials are used, then manufacturing is simple, but lyophobic performance cannot be maintained during high-temperature annealing

Engineering Contradiction:
Improvelyophobic performance under annealingVSAvoidmaterial composition complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The invention introduces fluorinated cyclic carbonate and fluorinated cyclic carboxylate compounds with specific molecular structures and chemical properties that remain stable under high-temperature annealing conditions (up to 200°C or higher). These compounds maintain the contact angle above 90° even after thermal processing, resolving the issue of lyophobic performance degradation during annealing by selecting materials with appropriate thermal stability parameters.

Inventive Principle:
Principle #35Parameter changes

3Reliability

If plasma treatment is applied repeatedly to maintain lyophobic performance, then contact angle is restored, but processing time and complexity increase

Engineering Contradiction:
Improvelyophobic performance consistencyVSAvoidtotal processing time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The invention incorporates fluorinated cyclic carbonate and fluorinated cyclic carboxylate compounds into the pixel defining layer during the initial coating and curing process, establishing permanent lyophobic properties before subsequent manufacturing steps. This preliminary incorporation eliminates the need for repeated plasma treatments to restore contact angle, reducing total processing time while maintaining consistent lyophobic performance throughout the manufacturing sequence.

Inventive Principle:
Principle #10Preliminary action

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 method ensures long-term maintenance of lyophobic performance and contact angles up to 110°, preventing degradation of the pixel defining layer during extended use or high-temperature processes.

Implementation Method 1

subjecting the first pattern to a surface treatment with a self-assembled monomolecular layer to form a fluorinated monomolecular layer on a surface of the first pattern

Methodology Applied
Scientific EffectSelf-assembly: Self-Assembly

Implementation Method 2

which forms a covalent bond and maintains lyophobic performance without being affected by cleaning or annealing processes

Methodology Applied
Scientific EffectCovalent bonding: Chemical Bonding

Data Source

PatentEP3270436B1Method for preparing a display substrate
Publication Date: 2021.10.06 BOE TECHNOLOGY GROUP CO LTD
  • EP3270436B1 patent drawingFigure 1~3a
  • EP3270436B1 patent drawingFigure 3b~5a
  • EP3270436B1 patent drawingFigure 5b~7b

AI summary

A method for preparing a display substrate, including forming a pixel defining layer (20) on a substrate (100), wherein forming the pixel defining layer(20) includes: forming a basic pattern (200) of the pixel defining layer on the substrate (100); the basic pattern (200) of the pixel defining layer comprises a first pattern (200a) of inorganic material, the first pattern (200a) being a top part of the basic pattern (200) of the pixel defining layer; subjecting the first pattern (200a) to a surface treatment with a self-assembled monomolecular layer to form a fluorinated monomolecular layer (210) on the surface of the first pattern, thereby forming the pixel defining layer (20). The lyophobic performance of the pixel defining layer formed by the method may be maintained for a long time.