DISCOVER THE MATERIALS
CORONAVIRUS &
TECHNOLOGIES FOR MASK Surgical masks are the most widely used masks in the world today. They can prevent bacteria from the outside world and can also help capture bacteria from droplets and aerosols from the wearer's mouth and nose. In this summary, we will discover the materials and techniques commonly used to produce masks. • • • • •
The structure and materials of mask Schematic diagram of blocking effect Diameter comparison of hair, spun viscose fibre and meltblown fibre Production of PP fibre and meltblown nonwovens New technologies for mask
THE STRUCTURE AND MATERIALS OF MASK Medical-surgical masks are generally made of three layers (or four layers as illustrated below) of non-woven fabric. The materials are spunbond + meltblown + spunbond (SMS). The outer layer of the mask is designed to trap and denature cell structures of bacteria and viruses. The second layer is considered as the germ-killing layer that effectively neutralises all airborne germs using its dyed rayon with metallic ions (but this layer is optional). The third layer is a non-active layer of melt-blown PPE that filters the finer particles (virus). Lastly, the spun-bond PPE layer is the final barrier avoiding prolonged skin contact from irritations.
THE
STRUCTURE AND MATERIALS OF MASK 1. Outer Layer: Spunbond polypropylene (PP) for waterproof, 20 gsm mask material is made in a spunbond process, which involves extruding the melted plastic onto a conveyor. 2. Second Layer (Optional): Rayon with Copper and Zinc ions to kills germs.
3 layers mask
3. Barrier Layer: Meltblown layer, 25 gsm fabric is made through meltblown technology, which is a similar process where plastic is extruded through a die with hundreds of small outlets and blown by hot air to become tiny fibres, again cooling and binding on a conveyor. These fibres are less than a micron in diameter. 4. Inner Layer: Spunbond polypropylene (PP) for waterproof, 20 gsm mask material is made in a spun-bond process.
4 layers mask (2020). Retrieved from https://respokare.com
SCHEMATIC
DIAGRAM OF BLOCKING EFFECT
We usually say that the mask is made of nonwoven fabric that has better bacteria filtration and air permeability while remaining less slippery than woven cloth. The material is most commonly comprised of polypropylene, either 20 or 25 grams per square metre (gsm) in density. Masks can also be made of polystyrene, polycarbonate, polyethylene, or polyester. Compared with textile fabric, non-woven fabric is made of directional or random fibres.
Schematic diagram of blocking effect of SMS structure on various substances (2020). Retrieved from https://www.steeljrv.com/how-to-choose-a-face-mask.html#Why_can_wearing_masks_prevent_infectious_diseases
DIAMETER COMPARISON
Diameter comparison of hair, spun viscose fibre and meltblown fibre (2020). Retrieved from http://www.technicalnonwovens.com
We will make a comparison between spunbond layers fibre, meltblown fibre and hair as : 1 / 3 of hair diameter is close to spunbond layer fibre, and 1 / 30 of hair diameter is close to meltblown layer as the photo of fibre diameter. Of course, researchers are still developing finer fibres to ensure better antibacterial barrier. (2020). Retrieved from https://www.steeljrv.com/how-to-choose-a-face-mask.html#Why_can_wearing_masks_prevent_infec tious_diseases
PP fibre (2020). Retrieved from By https://www.steeljrv.com
Nonwoven production also needs fibre materials. Polypropylene particles are used to melt and shape, while high melting refers to the polypropylene fibre material, which is the core raw material for the production of masks, which is the following one by one polypropylene fibre.
PRODUCTION OF PP FIBRE AND MELTBLOWN NONWOVENS The meltblown process is a nonwoven manufacturing system involving direct transformation of a polymer into continuous filaments, integrated with the transformation of the filaments into a random laid nonwoven fabric.
Developments in manufacturing techniques for technical nonwovens (2018). Retrieved from http://www.sciencedirect.com/topics/ engineering/melt-blown-process
The processing is to draft the polymer melt fine flow extruded from the spinneret hole of the die head with high-speed hot air, to form the microfiber and combine it on the condensing net conveyor belt or roller, and then make the nonwovens by self-adhesion. It will also add Electret treatment. The principle is to make the surface of the filter material more open, capture the particles, and increase the charge density, so the adsorption and polarisation effect of the particles is stronger to prevent the virus. H.-g. Geus (2016). . Retrieved from https://www.sciencedirect.com/topics/ engineering/melt-blown-process
NEW TECHNOLOGIES FOR
HeiQ Viroblock NPJ03 Technology : Anti-viral Defenses by zinc oxide, silver HeiQ Viroblock NPJ03 is a unique combination of the registered silver technology for antiviral and antibacterial effect and the vesicle technology as a booster. HeiQ Viroblock is designed to inhibit the growth and persistence of bacteria and enveloped viruses, such as coronavirus, on textile surfaces. (2020). Retrieved from https://heiq.com/technologies/heiq-viroblock/
MASK
Microban and ChromaSol from Material ConneXion in MRC Technology: Anti-viral Defenses by zinc oxide, silver Silver ion antimicrobial technology is a silver-based active ingredient that can be incorporated into polymers, coatings, textiles and more to offer continuous product protection against bacterial growth.
From bagasse to a new nano-particle removing material.
New mask material can remove virus-size nanoparticles by QUT Techology : Biodegradable anti-pollution masks A new material created by QUT scientists is very effective at removing particles smaller than 100 nanometres, which is in the range of a virus and it is easier to breathe through than high-quality face masks - important for people with existing respiratory issues. It is biodegradable and made from waste plant material from bagasse to a new nano-filter. (2020). Retrieved from https://www.qut.edu.au/research/article?id=161470