What Are the Types of Nonwovens?

What Are the Types of Nonwovens?
Airlaid Nonwovens
Compared to other nonwovens technologies, airlaid has the unique ability to lay down short fibers, either 100% pulp fibers, or mixtures of pulp and short cut synthetic fibers, to form a homogeneous and continuous web. It is also possible to mix in superabsorbent powders or fibers thereby creating highly absorbent webs.

Air Through Bonding (Thermal Bonding)
Through air bonding is a type of thermal bonding that involves the application of heated air to the surface of the nonwoven fabric. During the through air bonding process, heated air flows through holes in a plenum above the nonwoven material.

Meltblown
Meltblown nonwovens are produced by extruding melted polymer fibers through a spin net or die consisting of up to 40 holes per inch to form long thin fibers which are stretched and cooled by passing hot air over the fibers as they fall from the die. The resultant web is collected into rolls and subsequently converted to finished products.

Spunlace (Hydrotentanglement)
Spunlace (also known as hydroentanglement) is a bonding process for wet or dry fibrous webs made by either carding, airlaying or wet-laying, the resulting bonded fabric being a nonwoven. This process uses fine, high pressure jets of water which penetrate the web, hit the conveyor belt (or “wire” as in papermaking conveyor) and bounce back causing the fibers to entangle. Spunlace non woven fabrics used short staple fibers, the most popular is viscoseand polyester staple fibers but polypropylene and cotton are also used. Main applications for spunlace include wipes, facial sheet masks and medical products.

Spunlaid (Spunbond)
Spunlaid, also called spunbond, nonwovens are made in one continuous process. Fibers are spun and then directly dispersed into a web by deflectors or can be directed with air streams. This technique leads to faster belt speeds, and cheaper costs.

Spunmelt/SMS
Spunbond has been combined with melt-blown nonwovens, conforming them into a layered product called SMS (spun-melt-spun). Melt-blown nonwovens have extremely fine fiber diameters but are not strong fabrics. SMS fabrics, made completely from PP are water-repellent and fine enough to serve as disposable fabrics. Melt-blown is often used as filter media, being able to capture very fine particles. Spunlaid is bonded by either resin or thermally.

Wetlaid
In the wetlaid process, staple fibers of up to 12 mm fiber length, very often mixed with viscose or wood pulp, are suspended in water, using large tanks. Afterwards the water-fiber- or the water-pulp-dispersion is pumped and continuously deposited on a forming wire. The water is sucked off, filtered and recycled. Besides synthetic fibers, glas ceramic and carbon fibers can be processed.