Face mask production complexities --------------------------------------- Higher than usual demand for a niche synthetic fibre is contributing to a global shortfall in protective masks and gowns for healthcare workers --------------------------------------- SPUNBOND MELTBLOWN SPUNBOND (SMS) MATERIAL Tri-laminated, non-woven fabric made from polypropylene fibres --------------------------------------- MELTBLOWN MANUFACTURING --------------------------------------- PERSONAL PROTECTIVE EQUIPMENT (PPE) SMS is used for face masks and other items like gowns, coveralls, lab coats, caps and boot covers --------------------------------------- 1 Polypropylene: Thermoplastic chips added Plastic melted, extruded, filtered and metered to produce slender threadlike fibres 2 High velocity hot air: Strands (one thousandth of millimetre thick) sprayed onto rotating drum where they form tangled mesh. Electrostatic charge added to attract aerosols 3 Spooling reel Highly specialised machinery: Can take many months to assemble Hot air pipe Motor --------------------------------------- LAMINATE Meltblown polypropylene: Excellent, but weak, fluid and particulate barrier --------------------------------------- Final product can be treated to repel alcohol, oil and blood. Offers bacterial filtration efficiency of 95%-99% --------------------------------------- Spunbond polypropylene: Thermally-bonded web- like structure adds high tensile strength Rotating drum: Carries meltblown polypropylene onto spooling reel for collection --------------------------------------- China: Number one manufacturer of meltblown material, producing around 25,000 tonnes per year --------------------------------------- Sources: Textile Innovations, GPM Machinery, Reuters Picture: Getty Images © GRAPHIC NEWS