Due to the impact of emergencies, the demand for masks has increased due to increased equipment. Among them, medical surgical masks and N95 masks generally adopt a multi-layer structure, referred to as SMS structure: the inner and outer sides are spunbond layers (S); the middle is the meltblown layer ( M), generally divided into single layer or multilayer. Flat masks are generally PP spunbond + meltblown + PP spunbond, and three-dimensional cup masks are generally PET polyester needle punched cotton + meltblown + needle punched cotton or PP spunbond.
It can be seen that the non-woven fabrics required for masks are mainly spunbonded and meltblown, among which spunbonded non-woven fabrics use a relatively thick fiber diameter of about 20 microns. The process of meltblown non-woven fabric is to feed polymer-melt extrusion-fiber formation-fiber cooling-net formation-reinforcement into cloth. Melt-blown fibers can reach 1-5 microns in diameter, and are generally made of polypropylene with high-melt fat fibers. These ultra-fine fibers with unique capillary structure increase the number and surface area of fibers per unit area, thereby making melt-blown fabrics With good filtering, shielding, thermal insulation and oil absorption, meltblown cloth can be called the "heart" of medical surgical masks and N95 masks. However, the domestic output of meltblown non-woven fabrics is relatively low.
