Non-woven fabric manufacturers tell you the secret of meltblown fabric

At present, meltblown non-woven fabrics are widely used in the field of filter materials. Since the 1970s, various charging technologies and charging technologies by mixing different fibers have been developed and utilized. The direct result is the current electrostatic electret method (process). The current electret methods mainly include electrospinning, corona charging, friction electrification, thermal polarization, and low-energy electron beam bombardment. Due to the different electrostatic electret methods (processes) of the materials, the properties of the formed electrets are also quite different.





The filtration performance of meltblown non-woven fabrics is actually less than 70%. Purely relying on the mechanical barrier effect of the three-dimensional aggregates of meltblown superfine fibers with fine fibers, small voids and high porosity is not enough. Otherwise, blindly increasing the thickness of the material will greatly increase the filtration resistance. Therefore, melt-blown filter materials generally use electrostatic electret technology to add electrostatic charge to the melt-blown cloth, and use electrostatic methods to improve the filtration efficiency, which can reach 99.9% to 99.99%. That is, the KN95 standard.


The electret air filter material uses the electret polarity of the fiber itself to electrostatically adsorb the dust and trap bacteria and viruses. The ultra-fine fiber three-dimensional aggregation high porosity and fiber open electrostatic electret performance provide high efficiency and low resistance filtration quality. The mechanism of action of electret antibacterial meltblown cloth is that the strong electrostatic field and microelectronic current generated by the electret stimulate bacteria, cause their protein and nucleic acid to mutate and damage, destroy the surface structure of bacteria, cause bacteria to die, and tourmaline itself releases negative ions to block The metabolic process of some bacteria and microorganisms, including the respiratory system, enzyme activity, and material transfer from the cell wall, inhibits bacterial cells from playing an antibacterial effect.


Meltblown electret filter materials mainly capture particles through the dual effects of mechanical barrier and electrostatic adsorption. The mechanical barrier effect is closely related to the structure and properties of the material: when the meltblown cloth is corona charged, it has a voltage of several hundred to several thousand volts. Due to the repulsion of static electricity, the fibers diffuse into mesh holes, and the size between the fibers is much larger than The size of the dust, thus forming an open structure. When the dust passes through the meltblown filter material, the electrostatic effect can not only effectively attract the charged dust particles, but also capture the polarized neutral particles with the electrostatic induction effect. The higher the electrostatic potential of the material, the greater the charge density of the material, and the more point charges, the stronger the electrostatic effect. Corona discharge can greatly improve the filtration performance of polypropylene melt blown cloth. The addition of tourmaline particles can effectively improve the electret efficiency, increase the filtration efficiency, reduce the filtration resistance, increase the surface charge density of the fiber, and increase the charge storage capacity of the fiber network. The overall effect of adding 6% tourmaline electret is better. Too much electret material will increase the movement and neutralization of carriers.