Spunbond Nonwoven Fabric High-Throughput Filament Diameter Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Producing spunbond filament nonwoven fabrics with small diameter filaments at high production rates is challenging due to issues like fiber breaks and reduced process stability, forcing manufacturers to choose between low filament diameter and high production efficiency.
Innovation Solution
The process involves a spinneret with a high-density pattern of exit orifices and a controlled quench air system to achieve high throughput while maintaining small filament diameters, using a distributor to spread the molten polymer and a filter to prevent debris, and a pneumatic drawing unit to attenuate filaments effectively.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the polymer throughput rate is reduced to allow pneumatic drawing forces to reduce filament diameter, then small filament diameter is achieved, but production efficiency and cost-effectiveness deteriorate
Solution Approach 1:
The patent changes the physical parameters of the extrusion process by increasing melt temperature and extrusion pressure, allowing high throughput rates while maintaining small filament diameters through enhanced pneumatic drawing forces
Solution Approach 2:
The patent applies preliminary quenching of the extruded filaments before pneumatic drawing, which solidifies the filaments sufficiently to withstand the drawing forces while maintaining small diameters at high production rates
2Productivity
If high throughput rates are used to maintain production efficiency, then production cost is reduced, but filament diameter increases and process stability deteriorates
Solution Approach 1:
The patent modifies process parameters including extrusion temperature, pressure, and air-to-polymer ratio to enable high throughput operation while maintaining control over filament diameter through optimized pneumatic drawing
3Productivity
If high throughput rates are used to maintain production efficiency, then production cost is reduced, but process stability deteriorates due to fiber breaks and hard spots
Solution Approach 1:
The patent applies preliminary quenching to solidify filaments before drawing, preventing fiber breaks during high-speed operation and improving process stability
Solution Approach 2:
The patent optimizes process parameters including melt temperature, extrusion pressure, and quench air conditions to eliminate hard spots and fiber breaks, enabling stable high-rate production
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
This approach enables the production of spunbond filament nonwoven fabrics with small diameters at high rates while maintaining process stability, improving tensile strength and uniformity, and reducing production costs.
Implementation Method 1
extruding a molten thermoplastic polymer from a plurality of fine capillaries as molten filaments
Implementation Method 2
The molten filaments are quenched to at least partially solidify them
Implementation Method 3
the molten filaments are quenched to at least partially solidify them and then they are attenuated by one or more high velocity air streams which reduce their diameter
Implementation Method 4
the pneumatic drawing of the filaments in the spunbond process also acts to increase the crystallinity of certain polymers, such as propylene polymers, which provides the formed filaments and fabrics with increased tensile strength
Data Source
AI summary
Spunbond fiber nonwoven webs (and methods for making the same) comprising small diameter filaments at high rates of production and with high process stability.