Non-wovens are chosen for their adaptability and cost efficiency, and in some cases there are no other feasible alternatives. We are accustomed to seeing non-wovens in car interiors, as surface materials on hygiene products and as moulded furniture, but they are often hidden from view in sound absorbents, in dishwashers, as dust guards under spring mattresses and as fillers in clothing.
Melt-blown - manufacturing non-wovens with very fine fibres
Melt-blown is a special technique for manufacturing non-wovens with very fine fibres, down to 0.5 μm. The fibres are elongated by blowing hot air at high speed concentrically along the fibres. The technique enables a wide selection of polymers, such as PP, PET, PBT and PLA, with a broad viscosity range. We can also mix in additives and modify the polymer, which provides virtually unlimited opportunities for ideas and approaches. Materials can even be produced with properties similar to those of a traditional spun bond.
The machine is designed for use in, for example, projects for air filters, medical technology products, sound absorbents, recycling and much more. The collected material is 37 cm wide with a surface weight of between 1 and 500 GSM, which is primarily dependent on the pick-up speed. To calculate the production speed, a mass flow is needed that is dependent on the polymer type and viscosity, but for polypropylene it is 4.5 kg/hour, which corresponds to 1200 m/hour if the surface weight is 10 GSM. In other words, a few square metres of material, which is usually all that is needed, can be rapidly produced.
To further modify and functionalise the surface of the fibres, our atmospheric plasma equipment can be used. There are many exciting opportunities here, such as making super hydrophobic surfaces or increasing colourability.
Swerea can analyse non-wovens using a wide range of methods, including several of the methods that have been developed by the European trade organization EDANA. Moreover, we can handle most aspects of chemical analysis and examine the material with scanning electron microscopy.
Contact and more information
marten.alkhagen [at] swerea.se