What Are Thermal Bonded Nonwovens?

Thermal bonding is a technique for bonding a web of fibers in which a heat or ultrasonic treatment, with or without pressure, is used to activate a heat-sensitive material, according to INDA, the association of the nonwoven fabrics industry. The material may be in the form of homofil fibers, bicomponent fibers, and fusable powders, as part of the web. The bonding may be applied all over (e.g. through or area bonding) or restricted to predetermined, discrete sites (e.g. point bonding).

There are different types of thermal bonding systems that can be used:

Calender bonding thermally bonds a web of loose fibers by passing them through the nip of a pair of calender rollers, of which one or both are heated.

Through air bonding (or air through bonding) is a bonding system that that uses high temperature air to fuse the web’s fibers. There are two basic systems: blowing hot air through the web in a conveyor oven or passing heated air through the web on a rotating drum.

Ultrasonic bonding is the use of high frequency sound to generate localized heat through vibration and cause thermoplastic