Thermobonding of Nonwovens has become by now one of the most important ways of bonding nonwovens. Hightechnological Thermobonding Calenders are equipped with Swimming Rolls. The Rolls allow for an even pressure throughout the full width of the nip, irrespective of the amount of pressure.
The results:
evenly bonded optimum adaption of the pressure to types of fibre, weight of web and speed.
Thermobonding Calenders are equipped with closed circuit oil heating allowing for oil temperatures up to about 300°C and more. Dependent on type of fibre, weight of web and speed, this will correspond to a surface temperature of 140 - 150°C for Polypropylene and 230 - 240°C for Polyester webs.
Spunlace has been called needlepunching with water. A fiber web is made from cards or air lay machines. This web is subjected to high water jets, and then the fibers entangle each other to form nonwovens.
Spunlacing Technological advantages:
- extremely low web weights and high production speeds
- bonding of all kinds of fibers without chemical binders or melt fibers
- spunlace products are easy to recycle
- products of 100% natural fibers can be produced
- strength of spunlace products is much higher for the same fiber weight than after mechanical needling
Needlepunching is an entangling, bonding and compacting process. It is a process where needles of various configurations penetrate a given structure. Needlepunched nonwovens begin with one of the basis fiber forming processes such as carded, air laid and spunbond.