Mask Making Materials
Jun 15, 2017
Medical masks and protective masks are non-woven materials, composed of directional or random fibers, generally multi-layer structures, usually referred to as SMS structures (2 layers of S layers and 1 layer of M layers). At present, the highest number of layers in China is 5 layers, namely SMMMS (2 layers S layer and 3 layers M layer). S stands for spunbond layer (Spunbond), M stands for barrier layer or meltblown layer M (Meltblown), both of which are composed of polypropylene (PP). The M layer uses a melt-blown non-woven fabric as a filter layer because its fibers are randomly distributed and have complex three-dimensional pores. The fibers of the spray filter material are randomly distributed to form a large number of tiny pores, and the pore distribution is uniform, the filtration resistance is small, and the filtration efficiency is high, so that the filtration performance of the non-woven medical protective mask is far better than that of the traditional gauze mask.
What is meltblown cloth:
Meltblown cloth is a film made of polypropylene with a high melt index and laminated in random directions by many crisscross fibers.
The fiber diameter range is 0.5~10 microns, and the fiber diameter is about one-thirtieth of the hair.
An ordinary medical mask requires about 1g of meltblown cloth + 2g of spunbond cloth;
An N95 mask needs about 3-4g of meltblown cloth + 4g of spunbond cloth.
Plain Medical Masks: Generally, flat masks are 3 layers, PP25g+meltblown cloth 25g+PP 25g, among which the filtration efficiency we often say mainly depends on all the meltblown cloths in the middle layer, generally 80, 90, 95, 99 of these filters Efficiency, conventional disposable medical masks use 99 meltblown cloth. There will also be 2 layers, that is, there is no meltblown cloth in the middle.
KN95 masks: Generally, KN95 masks are 5 layers, and there will also be 4 layers
1. The outermost layer is a non-woven fabric with waterproof treatment, which is mainly used to isolate the liquid sprayed by the patient and has the effect of preventing droplets.
2. The second layer is hot air cotton, which mainly plays the role of thermal insulation, moisture-proof and moisture-proof, and improves the comfort of the wearer.
3. The third and fourth layers are two layers of electret-treated melt-blown cloth. High-quality KN95 masks generally use two layers of melt-blown cloth with a weight of more than 25 grams to ensure that bacterial suspended particles can be basically filtered. important core layer.
4. The innermost layer is soft and skin-friendly non-woven fabric, which is not allergic to wear and improves the wearer's comfort.
