To talk about the production process of masks, we must first talk about the core raw material of masks: non-woven fabrics. Non-woven fabric is non-woven fabric. Although it is called non-woven fabric, the formation of non-woven fabric still needs fiber? Some friends may wonder, isn’t cotton fiber? Isn’t it possible to use cotton? The answer is no. You don't need cotton but also use fiber. Of course, you choose synthetic fiber!
The non-woven fabric uses pp polypropylene, and the molten pp polypropylene is blown into extremely fine fibers through high-speed hot air. Fly onto a roller, the fibers are randomly bonded to each other at high temperature, continuously rolling, and superimposed into a cloth. Here is a key quality indicator of non-woven fabrics, that is, the weight per unit area of ​​non-woven fabrics. The grammage represents the density and thickness of the non-woven fabric structure.
This kind of fiber can be as thin as 0.25 microns, and there must be gaps between the fibers, but the layers are squeezed and bonded together to form a labyrinth of channels, so that the non-woven fabric has its own natural filtering properties. For example, the droplets produced by our sneeze are 0.5 to 12 microns in diameter, which is very dust-proof and anti-droplet. However, this does not reach the medical grade level. At most, it is a dust mask. To reach the medical grade, the next important step is to make the fiber electrostatically charged, and increasing the electrostatic absorption effect can further improve the filtration efficiency. This is the electret charging process of the filter material.
In this way, 95% of the filtration efficiency can be achieved to prevent viruses and bacteria? Still can not! Because medical masks need to be sterilized by ethylene oxide before they leave the factory, and they have to be left to stand for a period of time until they reach the residual standard before leaving the factory.
The above is the analysis of the production process of medical masks that meet the standard