Due to the spread of COVID-19, there is a surge in the demand for surgical masks and N95 respirators. As the demand for protective clothing and face masks continue to grow, there is a rise in the demand for raw materials used for their production. Here is a list of the raw materials used for the production of protective face masks and clothing.
The requirement for protective clothing is stated in Chinese national standard GB 19082-2009. It is applicable to medical disposable protective clothing which helps maintain a barrier and provides protection against the infectious patient blood, secretions, body fluids, and airborne particulate matter. As per the European EN standard, the chemical protective clothing should comply with the European standard for Personal protective equipment (PPE) and has defined six types of protective clothing as listed below.
- EN 943-1/2: Airtight protective clothing
- EN 942-1: Non-airtight protective clothing
- EN 14605: Liquid Tightness Protective Clothing
- EN 14605: Aerosol tightness protective clothing
- EN ISO 13982-1/2: Protective clothing against solid particles
- EN 13034: Mild chemical splash protection
Medical protective clothing is a type of protective clothing that is suitable for medical personnel, not only to drain moisture but to protect the medical personnel from the spread of bacteria and virus. The protective clothing should be breathable and comfortable to wear. It is a dust protector and resists the invasion of alcohol, water, oil, and effective anti-static from entering.
Medical protective clothing is divided into woven, non-woven and composite material based on the structure of the fabric. It is further divided into limited use, disposable use and reusable as per its life. The clothing is also divided into coating, laminating and fishing as per the composite technology. The following raw materials are used in protective clothing that is developed and sold currently.
Polypropylene spunbond fabric
Polypropylene spunbond fabric is made by stretching the polypropylene to create a filament. It is then laid into a mesh and is bonded into a non-woven fabric. The cloth can be treated with antistatic and antibacterial treatment. It is made into antistatic protective clothing and antibacterial protective clothing. It has disposable use and a low price which makes it ideal for use in the current situation. The material reduces cross-contamination rates and has been pushed abroad for a long period of time since its introduction. It has low hydrostatic pressure and a poor barrier efficiency against viral particles. It can only be used as a general protective item like sterile wraps or sterile surgical gowns.
Nonwovens made of polyester fiber and wood pulp
Material made from non woven composite is reinforced with polyester webs entangled with wood pulp paper. It is made from wood pulp fibers and polyester staple. It is soft to touch and is close to traditional textiles. Nonwoven made from polyester fiber can be treated by anti-alcohol, anti-oil, anti-blood, antibacterial and antistatic. Its antistatic pressure is low and the barrier efficiency is poor. Hence, it is not ideal to be used for protective clothing materials.
Polypropylene spunbond-meltblown-spunbond composite nonwovens, i.e. SMS
This meltbrown non woven is made by drawing melt stream of polymer extruded from the spinneret holes of the dyes. It is done with the help of a high speed hot air stream. It helps form microfine fibers which are collected on a roller and bonded to themselves. This material is known for fine fiber, it is soft and fluffy, has a large surface area, high filtration efficiency, low filtration resistance and poor abrasion resistance. The spun bond fiber threads are dense and the web is made of continuous filaments whose break strength is greater than that of melt blown cloth. It compensates for the shortcomings of the meltblown cloth. It can be treated with anti-oil, anti-blood, anti-alcohol, anti static, anti bacterial and anti aging treatments. The material has best properties that include high breathability, pleasing appearance, soft feel, strong filtering results, high hydrostatic pressure resistance, and strong alkaline and acid resistance.
High polymer coated fabrics
Polymer coated fabrics are made by laminating ordinary fabrics with a special fit through the process of lamination.Various types of coatings are used for protective fabrics including polyethylene, PVC, polychloroprene and other synthentic rubbers. It is protective, waterproof and works are a barrier against bacterial particles. It can also be reused but the moisture permeability is poor. Large amount of human sweat cannot be excreted and the comfort level is low. The latest development is the use of microporous Teflon film and fabric composite to get a breathable and waterproof function.
The best way to fight COVID-19 is to use a face mask. There are different types of masks available in the market. The body of a surgical mask has three layers of non-woven fabric, using SMS structure. The material is spunbond non woven fabric in the three layers and the outer layer is anti droplet while the inner layer is of moisture absorption. Medical N95 masks are made of five layers for additional protection.
Hence, the two most important materials are spunbond fabric and melt blown nonwoven fabric. The inner and outer layer of spun bonded nonwovens are made of polyester and polypropylene while the middle layer is made of high fusion finger polypropylene.
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