There is a long way from granule to nonwoven in a spunbond/spunmelt production and the process demands attention to detail in every link of the chain.

The short version goes like this:

• Granulate
The fibre spinning beams are fed with PP granules.

• Fibre extrusion  
The PP granules are melted/extruded and spun to form spunbond fibres and meltblown fibres. 

For the spunbond process, it passes through a die plate with holes spread over multiple adjacent rows. The fibres are stretched and deposited on a moving belt. 

Spunbond fibres typically have a diameter in the range of 13-17 µm, 1,2-2,0 dtex. 

For the meltblown process, it passes through a die plate - with holes in a row. It results in a layer of thin filaments. These filaments are afterwards stretched while passing through a high velocity hot air stream. 

Meltblown fibres typically have a diameter in the range of 1-5µm. 

The spunbond fibres provide strength to the final web, whereas the thinner meltblown fibres provide water barrier to the final web. 

The resulting product is often referred to as SMS or SMMS to signify that the spunbond(S) layers surround the meltblown(M) layers. 

• Thermal bonding
The web is terminally bonded using heated rollers to form a final nonwoven with optimum characteristics. 

• Application of spinfinish
For some products hydrophilic or antistatic properties are desired and in these cases this is obtained by the in-line application of spinfinish. 

• Roll-up
The spunbond/melt fabric is scanned by cameras for quality control before being rolled onto tubes in large jumbo rolls, and subsequently cut into smaller rolls and packed according to customer requirements. 

• Bicomponent
When ultimate softness and enhanced drapeability is desired, this can be obtained by utilising bicomponent spunbond technology, which differs from standard products in that the spunbond fibres consist of polypropylene and polyethylene in a core/sheath configuration, where the polyethylene sheath provides the enhanced softness and drapeability characteristics. 

Bicomponent products are produced in our Malaysia facility.