Non-woven fabrics that don't require weaving

In the public's perception, traditional fabrics are woven. However, the name of non-woven fabric is puzzling; does it really not require weaving?

Non-woven fabric, also known as non-woven cloth, is a fabric that does not require weaving or knitting. Unlike traditional fabrics made from interlacing and knitting yarns, it is made by directly bonding fibers together using physical methods. In terms of manufacturing process, non-woven fabrics directly utilize polymer chips, short fibers, or long filaments. The fibers are formed into a web through airflow or mechanical means, and then solidified through hydroentanglement, needle punching, or thermal rolling. Finally, it is finished to form a non-woven fabric.

The production process of non-woven fabrics can be divided into the following steps:

1. Fiber combing; 2. Fiber web formation; 3. Web fixation; 4. Heat treatment; 5. Final finishing.

According to the formation of non-woven fabrics, they can be classified as:

(a) Hydroentangled Nonwovens: High-pressure micro-water jets are sprayed onto a single or multi-layer fiber web, causing the fibers to entangle with each other and thus consolidate the fiber web.

(b) Heat-bonded Nonwovens: This refers to adding fibrous or powdery heat-sealable bonding materials to the web, so that the web melts upon heating and then cools to consolidate into fabric.

(c) Pulp Air-laid Nonwovens: Also known as dust-free paper or dry process paper nonwovens. It uses air-laid technology to transform wood pulp fibers into single fibers, using airflow to condense the fibers onto a forming screen and then consolidate them into fabric.

(d) Wet-laid Nonwovens: The fiber raw materials in the aqueous medium are opened into single fibers, and different fiber raw materials are mixed to form a fiber suspension slurry that is transported to the web forming unit for web forming and consolidation in a wet state.

(e) Spun-bonded Nonwovens: After the polymer is extruded and stretched to form continuous filaments, it is laid into a web. The fiber web is then bonded or mechanically consolidated to form a non-woven fabric.

(f) Melt-blown Nonwovens: The production steps are polymer input - melt extrusion - fiber formation - fiber cooling - web formation - consolidation into fabric.

(g) Needle-punched Nonwovens: This is a type of dry non-woven fabric, which uses the puncture action of needles to consolidate the fluffy web into fabric.

(h) Stitch-bonded Nonwovens: This is a type of dry non-woven fabric, which uses warp-knitted loop structures to consolidate webs, yarn layers, non-woven materials (such as plastic films), or their combinations into non-woven fabrics.

The fiber raw materials required for making non-woven fabrics are very extensive, such as cotton, flax, wool, asbestos, glass fiber, viscose fiber (rayon), and synthetic fibers (including nylon, polyester, acrylic, polyvinyl chloride, vinylon, etc.). However, nowadays, cotton fibers are no longer the main material for making non-woven fabrics; rayon and other fibers have replaced them.

Non-woven fabrics are also a new type of environmentally friendly material. They are moisture-proof, breathable, elastic, lightweight, non-combustible, easily degradable, non-toxic and non-irritating, come in rich colors, are inexpensive, and recyclable, so their applications are very wide-ranging.

In industrial materials, because non-woven fabrics have high filtration efficiency, insulation, heat insulation, acid resistance, alkali resistance, and tear resistance, they are often used in the production of filter media, sound insulation, electrical insulation, packaging, roofing, and grinding materials. In the daily necessities industry, they can be used as clothing interlining materials, curtains, wall decoration materials, diapers, and travel bags. In medical and health products, they can be used in the production of surgical gowns, patient gowns, masks, and sanitary belts.