Composite Nonwoven Systems

As described above, meltblown and spunbond have different diameter filaments and other property variations. When the two processes are combined, this allows a multitude of technical benefits to be achieved.

Meltblown / Spunbond multilayer fabrics include SM (spunbond-meltblown) and SMS (spunbond-meltblown-spunbond), which are frequently used in filtration applications.

SMS is a tri-laminate nonwoven fabric. It is made up of a top layer of spunbond polypropylene, a middle layer of meltblown polypropylene and a bottom layer of spunbond polypropylene. Multi-denier spinning allows for the combination of these spunbond and melt blown materials into a single nonwoven web. This web is then pre-bonded and passed through calendar rollers for thermal bonding.

There is even further potential for multiple combinations of meltspun and spunbond materials, such as SMMS, SSMMS and SMMMS.

Other variations and benefits

Bi-component continuous filaments that consist of more than one polymer type arranged in different configurations within the filament cross section (eg, side-by-side, core-sheath, segmented pie, and islands in the sea) can be utilised to produce nonwoven fabrics containing microfibres and sub-microfibres by splitting or fibrillating the filaments in the web after it has been extruded.

Meltblown fabrics are frequently combined with nanofiber webs to achieve greater filtration efficiency.

Composite nonwovens have the advantage of flexibility to bond with other types of webs, resisting shedding, with relatively higher mechanical strength, and are stable and resilient. They also have the advantage of forming functional fibres, such as antibacterial, and receiving permanent treatment (eg, flame retardancy) at the fibre extrusion stage.

FET’s composite nonwoven systems are proven to provide solutions for nonwovens manufacturers and research establishments globally.