Filter Element with Hot-Melt Adhesive Fibers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing filter elements with fiber layers tend to delaminate, causing significant pressure drops and are complex to produce, especially when used in applications like motor vehicles, where air permeability is crucial.
Innovation Solution
A filter element comprising a first fiber layer, a second fiber layer, and an adhesive layer made of hot-melt adhesive fibers or dots with specific diameter and melting point ranges, which provides strong adhesion without significant pressure drop, produced through an electrospinning process and applied using techniques like heating to form discrete adhesive points.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If continuous adhesive layers are used to fix fiber layers, then adhesion strength is improved, but pressure drop increases significantly
Solution Approach 1:
The continuous adhesive layer is segmented into discrete adhesive points or adhesive fibers with diameters of 1-500 nm. This segmentation reduces the total adhesive material present while maintaining bonding effectiveness at critical locations, thereby reducing pressure drop while preserving adhesion strength.
Solution Approach 2:
Adhesion is concentrated at specific local points rather than distributed uniformly across the entire fiber layer surface. The adhesive points are strategically positioned to provide sufficient bonding strength only where needed, allowing air to flow more freely through non-adhesive areas and reducing overall pressure drop.
2Stability of the object's composition
If fiber layers are bonded to prevent delamination, then mechanical stability is improved, but air permeability deteriorates
Solution Approach 1:
The adhesive bonding is segmented into discrete points or fine fibers rather than continuous coverage. This allows the fiber layers to remain mechanically stable at bonded points while maintaining air permeability through unbonded areas, resolving the contradiction between stability and permeability.
Solution Approach 2:
The adhesive layer is designed with porous or discontinuous structure through the use of nanofibers or spaced adhesive points. This porous structure allows air to pass through while the adhesive portions provide mechanical stability, preventing delamination without significantly blocking air flow.
3Ease of manufacture
If adhesive layers are applied to fix fiber layers, then production complexity is reduced, but adhesion uniformity worsens
Solution Approach 1:
The adhesive fibers or dots are designed to self-align and self-bond during the filtering process. The adhesive material activates under operational conditions (moisture, temperature) and automatically bonds to the fiber layers without requiring precise positioning or complex application equipment, achieving both ease of manufacture and uniform adhesion.
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 filter element achieves strong adhesion between fiber layers with minimal impact on air permeability, reducing pressure drop and improving mechanical stability and separation performance, even under mechanical stress.
Implementation Method 1
an adhesive layer which connects the first and second fiber layers, the adhesive layer comprising hot-melt adhesive fibers
Implementation Method 2
the hot melt adhesive fibers have a melting point that is at least 30 ° C, preferably at least 80 ° C, below the melting point of the first and second fiber layers
Data Source
Figure 1~4
AI summary
A first fiber layer (1) bonds to a second fiber layer (3). First (2) and second (4) adhesive layers include hot-melt-type adhesive fibers, preferably with a fiber diameter in a range between 1 nanometer (nm) and 500 nm. The hot-melt-type adhesive fibers have a melting point at 30[deg] Celsius at least below the melting point of the first and second fiber layers. The second adhesive layer bonds the first fiber layer to the second fiber layer. An independent claim is also included for a method for producing a filter element.