Pleatable Nonwoven Filter Material With Gradient Fiber Distribution
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing filter materials face challenges in achieving low pressure difference and high separation performance while being environmentally friendly and cost-effective, with current production methods like electrospinning posing health and environmental risks and limiting fiber thickness.
Innovation Solution
A pleatable nonwoven material is produced by incorporating thinner fibers homogeneously within thicker fibers, with a diameter gradient and bonding them together from the same material, using a method that involves multiple spinning beams with angled spinnerets and high-viscosity polymer melts to achieve a homogeneous distribution, allowing for efficient filter performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of moving object
If electrospinning process is used to produce nanofibers, then fiber diameter can be reduced to below 1 μm, but large amounts of solvents are consumed and explosion risk increases
Solution Approach 1:
The patent changes the fundamental production parameter from solution-based electrospinning to melt-based extrusion. This parameter change eliminates solvent usage entirely, removing the associated explosion risks and environmental hazards while still achieving fine fiber diameters below 1 μm through controlled extrusion processes
Solution Approach 2:
The patent replaces the electrostatic field-based electrospinning mechanism with a mechanical extrusion system. This substitution eliminates the need for high voltage and solvent evaporation, thereby removing explosion risks and harmful vapor emissions while maintaining the capability to produce ultrafine fibers
2Manufacturing precision
If multiple coating layers are applied to improve separation performance, then filter efficiency increases, but pleating becomes extremely difficult and foldability is limited
Solution Approach 1:
The patent merges the support structure and filtering layers into a single integrated nonwoven material produced in one continuous process. This integration eliminates the need for separate coating layers, maintaining high separation performance while enabling easy pleating and folding throughout the material structure
Solution Approach 2:
Instead of applying multiple coating layers on top of a support material, the patent inverts the approach by incorporating filtering functions directly into the support material itself through homogeneous fiber distribution. This inversion eliminates the layered structure that complicates pleating while maintaining or improving separation performance
3Manufacturing precision
If fiber density is increased to improve separation performance, then particle capture improves, but pressure difference increases
Solution Approach 1:
The patent applies local quality by creating a homogeneous distribution of fine fibers throughout the entire nonwoven material volume rather than concentrating them in dense surface coatings. This uniform distribution optimizes particle capture efficiency while maintaining low pressure difference by avoiding localized density extremes
Solution Approach 2:
The patent creates a composite structure combining fine filtering fibers with coarser support fibers in a homogeneous matrix. This composite approach enables the fine fibers to provide separation performance while the coarser fibers maintain structural integrity and airflow channels, thereby reducing pressure difference
4Manufacturing precision
If very fine fibers are used to increase inner surface area, then separation performance improves, but mechanical strength decreases and material becomes brittle
Solution Approach 1:
The patent implements a nested structure where ultrafine filtering fibers are embedded within and supported by a matrix of coarser, mechanically stronger fibers. The fine fibers provide separation performance while being nested within the robust framework of thicker fibers that supply mechanical strength and prevent brittleness
Solution Approach 2:
The patent creates a composite material system where fine fibers (providing separation performance) are combined with coarser fibers (providing mechanical strength). This composite structure allows the fine fibers to function effectively without compromising the overall mechanical integrity of the filter material
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 solution results in a filter material with exceptional filter properties, low pressure difference, and high separation performance, while being environmentally friendly and cost-effective, with improved throughput and reduced risk of mechanical failure.
Implementation Method 1
a cone of compressed liquid polymer is discharged under pressure... the polymer threads thus produced are laid down on a conveyor belt
Implementation Method 2
spinnerets of various diameters are used while simultaneously producing and laying down higher- and lower-thickness polymer threads... the polymer threads leaving the spinnerets tangle before contact with the conveyor belt
Data Source
AI summary
A pleatable nonwoven material is provided, including thicker form-giving fibers and thinner fibers determining the filter effect, wherein the thinner fibers are incorporated largely homogeneously in the thicker fibers running in the direction along the surface of the nonwoven material and a distribution density gradient of the thinner fibers is established perpendicular to the surface of the nonwoven material such that the highest concentration of thinner fibers is in the region of the center or on one of the two outsides, wherein the thicker and thinner fibers are bonded together by solidification from the melted condition and are made from the same material.