WHAT ARE DRY-LAID NONWOVENS?
Dry-laid nonwovens are fabrics made from staple fibers by dry-laying process. Depending on the web formation and laying process, dry-laid nonwovens can be classified as air-laid nonwovens (aerodynamic web formation) and carded nonwovens (mechanical web formation).
The staple fibers used in dry-laid nonwovens have a length of 1.2 to 20cm or longer, which are long enough to be handled by conventional spinning equipment.

To bond and stabilize the webs, a couple of methods can be used:

* Thermal bonding
Thermal bonding is the process of using heat to bond or stabilize a web structure that consists of a thermoplastic fiber.
* Chemical bonding
The chemical binder is applied to the web and is cured. The most commonly used binder is latex, because it is economical, easy to apply and very effective.
* Needle punch
Needle punching is a process of bonding nonwoven web structures by mechanically interlocking the fibers through the web.
* Stitch bonding
Stitch bonding is a method of consolidating fiber webs with knitting elements with or without yarn to interlock the fibers. .
* Hydroentanglement (Spunlacing)
Hydroentanglement is a process of using fluid forces to lock the fibers together. This is achieved by fine water jets directed through the web.

Thermal bonding and chemical bonding (using latex) are the two most widely used bonding methods.
CHARACTERISTICS AND PROPERTIES
The web properties of carded nonwovens are normally anisotropic. That is, they are stronger in the direction in which the machine makes the fabric than in the direction across the machine. Some cards have randomizing sections, which change the direction of fibers as they are laid down in order to produce fabrics with increased cross directional strength. The weights and thicknesses of carded webs can be increased many-fold by overlapping layers of webs or by pleating a single web.

Air-laid nonwovens are highly absorbent, lofty fabrics or composites that are relatively cost competitive with similar weight nonwovens.
APPLICATIONS

The largest carded nonwoven market in the world is cover stock for absorbent products. Most of this cover stock is carded thermally point bonded polypropylene fabric which competes with spunbonded polypropylene nonwovens in cover stock applications.


The air-laid thermal bonded nonwovens have applications in absorbent cores and wiping products in hygiene industry.