Stretchable Fiber Sheet With Thermosetting Resin For Flexible Circuit Boards
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing stretchable conductive sheets face issues with heat resistance, durability, and integrity between the conductor layer and the fabric, limiting their application in flexible devices that require high heat resistance and flexibility.
Innovation Solution
A fiber sheet comprising a resin layer with a thermosetting resin and a fiber layer, which is stretchable by 1% or more and has an initial tensile elastic modulus of 1 MPa or more and 10 GPa or less, allowing for high heat resistance and flexibility.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a hot melt sheet is used to laminate the conductor layer to the fabric, then the conductor layer can be bonded to the fabric, but the sheet lacks heat resistance and may be torn during reflow soldering
Solution Approach 1:
The invention uses a composite structure combining a fabric base layer with a thermosetting resin layer containing conductive particles. This composite material provides both the bonding function and heat resistance, eliminating the need for separate hot melt sheets and ensuring integrity during reflow soldering.
Solution Approach 2:
The invention changes the material parameters by using thermosetting resin instead of thermoplastic hot melt sheets. This parameter change provides inherent heat resistance and dimensional stability, allowing the sheet to withstand reflow soldering temperatures without deforming or tearing.
2Strength
If a thermosetting polymer adhesive is used to wrap and bond the conductive wire, then the conductor can be attached to the base layer, but the adhesive layer may be torn and integrity between layers is insufficient
Solution Approach 1:
The invention creates a composite structure where conductive particles are embedded in a thermosetting resin matrix that is laminated to the fabric. This composite approach provides both bonding strength and layer integrity, as the resin acts as both adhesive and structural support.
Solution Approach 2:
The thermosetting resin layer serves as an intermediary between the fabric base layer and the conductive particles. This intermediary layer provides both mechanical bonding and electrical conductivity, ensuring integrity throughout the structure.
3Adaptability or versatility
If the fiber sheet is made highly stretchable to achieve 1% or more elongation, then flexibility is improved, but the initial tensile elastic modulus must be controlled to maintain durability against stretching
Solution Approach 1:
The invention optimizes the parameter of initial tensile elastic modulus to fall within 1 MPa to 10 GPa, which balances stretchability and durability. This parameter control ensures the sheet can be stretched by 1% or more while maintaining sufficient structural integrity.
Solution Approach 2:
The composite structure of fabric combined with thermosetting resin provides both flexibility and strength. The fabric contributes to stretchability while the resin matrix maintains structural integrity, achieving the desired balance between adaptability and durability.
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 fiber sheet provides excellent heat resistance and stretchability, enabling its use in various applications, including wearable devices and flexible display devices, without compromising the texture of the fabric or its durability against stretching and shrinking.
Implementation Method 1
a resin layer containing a thermosetting resin
Implementation Method 2
the fiber sheet is stretchable by 1% or more, and an initial tensile elastic modulus of the fiber sheet is 1 MPa or more and 10 GPa or less
Data Source
AI summary
A fiber sheet includes: a resin layer containing a thermosetting resin; and a fiber layer, wherein the fiber sheet is stretchable by 1% or more, and an initial tensile elastic modulus of the fiber sheet is 1 MPa or more and 1 GPa or less.