Low-Density Non-Woven Structures via Directed Hydroentanglement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional non-woven materials with high drapeability are often dense, thin, and smooth, lacking cushiony feel and exfoliating properties, which are desirable in personal care products.
Innovation Solution
A fibrous, non-woven structure with a unique combination of high drapeability and low density is achieved by stabilizing a layer of fibers into a web and contacting it with a stream of liquid, either directly or via an elastomeric support, to create a material with a density of less than 0.08 g/cc and drapeability of over 4 gsm/g, using methods like hydroentanglement and thermobonding.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If conventional spunlacing process is used to produce non-woven materials, then drapeability is improved, but density increases and cushiony feel is lost
Solution Approach 1:
The patent applies parameter changes by modifying the hydroentanglement process parameters, specifically directing liquid streams along or against the machine direction at controlled angles and velocities. This changes the fiber entanglement dynamics to produce a material with density below 0.08 g/cc while maintaining drapeability above 4 gsm/g, resolving the contradiction between drapeability and density.
Solution Approach 2:
The patent introduces a new dimensional parameter by controlling the angle and direction of liquid streams relative to the machine direction. By operating in this additional dimensional space (stream angle and direction rather than just perpendicular impact), the process achieves low density with high drapeability, overcoming the conventional trade-off.
2Ease of operation
If non-woven materials are made thin and dense, then drapeability is improved, but exfoliating properties and cushiony feel are reduced
Solution Approach 1:
The patent changes the physical parameters of the material by controlling fiber entanglement through directed liquid streams, achieving a unique combination of low density (below 0.08 g/cc) and high drapeability (above 4 gsm/g). This parameter optimization allows the material to be both drapeable and possess sufficient bulk for exfoliating properties and cushiony feel.
3Strength
If liquid streams are directed perpendicular to the web, then bonding strength is improved, but density increases
Solution Approach 1:
The patent inverts the conventional approach by directing liquid streams along or against the machine direction rather than perpendicular to the web. This reversal of the liquid stream direction achieves adequate bonding strength through hydroentanglement while maintaining low density (below 0.08 g/cc), resolving the contradiction between bonding strength and density.
Solution Approach 2:
The patent moves the liquid stream direction from a single perpendicular dimension to a multi-dimensional approach, allowing streams to be directed at various angles including along and against the machine direction. This dimensional flexibility enables the process to achieve bonding strength through extended entanglement pathways without increasing density.
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 resulting material is soft, comfortable, and provides enhanced absorbency and exfoliation capabilities, suitable for various personal care articles such as sanitary pads, tampons, and wipes, with improved mechanical integrity and thickness.
Implementation Method 1
methods of producing such materials via the hydroentanglement of non-wovens
Implementation Method 2
supporting the stabilized web on an elastomeric support member, moving the support member and stabilized web thereon
Data Source
AI summary
Provided are fibrous, non-woven structures having a drapeability of greater than about 4 gsm/g and a density less than about 0.08 g/cc, personal care articles comprising such structures, and methods of making such structures including methods comprising: stabilizing a thin layer of non-woven fibers into a stabilized web; supporting the stabilized web on an elastomeric support member; moving the support member and stabilized web thereon in a machine direction; and contacting the supported stabilized web with a stream of liquid.