The filtration performance of the mask is mainly determined by the filter material in the middle layer. The currently commonly used filter material is a melt-blown non-woven fabric made of polypropylene ultrafine fiber. It is light, thin, has good air permeability, and can filter efficiently. Particles in the air.
The thicker the filter material, the better. The performance of melt-blown non-woven fabrics produced by different manufacturers varies greatly, and the specific performance needs to be measured with professional equipment.
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