Metal-covered liquid crystal polyester multifilament
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Metal-covered polyallylate fibers used in smart textiles suffer from insufficient bending fatigue resistance and wearability due to low flexibility and high resistance increase upon repeated bending.
Innovation Solution
A metal-covered liquid crystal polyester multifilament with a metal thickness of 0.1 to 20 μm, where the percentage of stuck fibers is 75% or less, and the distance between farthest points on the metal-covered surface is 11 times or less the diameter, ensuring high tensile strength and flexibility.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If polyallylate fibers are used as conductive fiber substrate, then conductivity and strength are improved, but bending fatigue resistance and wearability deteriorate due to low flexibility
Solution Approach 1:
The invention changes the material parameter from polyallylate fiber to liquid crystal polyester fiber, which fundamentally alters the flexibility and mechanical properties. Liquid crystal polyester fiber inherently provides better flexibility while maintaining high strength, thereby improving bending fatigue resistance without sacrificing tensile strength. This material substitution resolves the contradiction by finding a fiber type that balances both strength and flexibility requirements.
Solution Approach 2:
The invention creates a composite structure by combining liquid crystal polyester fiber with metal coating. The liquid crystal polyester provides the flexible substrate while the metal layer (0.1-20 μm thick) provides conductivity and additional strength. This composite approach allows the fiber to maintain high flexibility for bending fatigue resistance while the metal coating ensures sufficient conductivity and tensile strength.
2Reliability
If metal coating thickness is increased to improve conductivity, then electrical performance is improved, but flexibility and wearability deteriorate
Solution Approach 1:
The invention optimizes the metal coating thickness parameter to a specific range of 0.1-20 μm. This parameter optimization ensures that the coating is thick enough to provide sufficient electrical conductivity for smart textile applications, while remaining thin enough to preserve the flexibility and softness of the underlying liquid crystal polyester fiber. The controlled thickness prevents excessive rigidity that would compromise wearability.
Solution Approach 2:
The metal coating is applied as a thin surface layer (0.1-20 μm) only on the outer surface of the liquid crystal polyester fiber, leaving the bulk material properties of the fiber intact. This localized application provides the necessary conductivity at the surface while the core fiber structure maintains its flexibility and comfort characteristics, thus resolving the contradiction between conductivity and wearability.
3Strength
If fibers are tightly bundled to improve structural integrity, then strength is improved, but flexibility and bending fatigue resistance deteriorate due to fiber sticking
Solution Approach 1:
The invention controls the bundling density and fiber arrangement parameters to achieve optimal structural integrity without excessive tightness. By adjusting these parameters, the multifilament structure maintains sufficient tensile strength while allowing individual fibers to move independently during bending, preventing sticking and maintaining flexibility. This parameter control resolves the contradiction between strength and bending fatigue resistance.
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 multifilament exhibits excellent wearability and bending fatigue resistance, maintaining low resistance values even upon repeated bending, making it suitable for smart textiles, electrodes, and electromagnetic wave shielding.
Implementation Method 1
a surface of each liquid crystal polyester monofilament is covered with a metal having a thickness of 0.1 to 20 μm
Implementation Method 2
a polyallylate fiber is usually used in a state where the spinning raw yarn has been solid phase polymerized by heat treatment to impart strength and elastic modulus
Data Source
AI summary
A metal-covered liquid crystal polyester multifilament, comprising: two or more metal-covered liquid crystal polyester monofilaments in which a surface of each liquid crystal polyester monofilament is covered with a metal having a thickness of 0.1 to 20 μm, wherein in a cross-sectional photograph measured by X-ray CT, a percentage of a number of stuck fibers in which the two or more metal-covered liquid crystal polyester monofilaments are stuck is 75% or less with respect to a total number of fibers.