What is filament spinning in Spunbonded No-woven Fabric?

Filament spinning is a crucial step in the manufacturing process of spunbonded non-woven fabric. It is the process by which molten synthetic polymer is extruded through spinnerets to form continuous filaments. These filaments serve as the basic building blocks for creating the non-woven fabric. Here's a closer look at filament spinning:

1. Polymer Extrusion:

The process begins with the selection of a synthetic polymer, often polypropylene (PP) or polyester (PET), in pellet form. These polymer pellets are melted down into a molten state in an extruder.

2. Spinnerets:

Spinnerets are specialized plates with a pattern of small holes or nozzles arranged in a specific configuration. The molten polymer is forced through these spinneret holes to form multiple fine streams of molten material.

3. Filament Formation:

As the molten polymer streams exit the spinneret holes, they are rapidly cooled, causing the material to solidify and form continuous filaments. The filaments are essentially long, thin strands of the polymer material.

4. Collecting the Filaments:

The solidified filaments are collected onto a moving conveyor belt or forming surface. The arrangement of these filaments on the belt creates a loose web of fibers.

5. Web Formation:

The collected filaments are laid down in a random or controlled arrangement on the conveyor belt, forming a loosely intertwined web of fibers. The web's density and uniformity can be adjusted by controlling the speed of the conveyor belt and the rate of filament deposition.

The filament spinning process is a key step in creating spunbonded non-woven fabric because it determines the initial structure of the fabric. The arrangement and bonding of these filaments during subsequent steps, such as bonding and finishing, will ultimately dictate the properties of the final non-woven fabric.

The use of continuous filaments distinguishes spunbonded non-woven fabric from other non-woven processes, such as staple fiber-based processes, where short fibers are used. Filament spinning contributes to the high strength, durability, and uniformity that are characteristic of spunbonded non-woven fabrics, making them suitable for a wide range of applications across various industries.