1. The fiber fineness of the filter material
It is expressed in terms of fiber diameter and the unit is micrometers. Generally, the fiber diameter of the filter material used for dust masks is preferably less than 5 microns. The diameter of the commonly used polypropylene ultrafine fiber is 4.0 microns, and the fiber diameter of the perchloroethylene ultrafine fiber filter material is less than 2 microns. The drug abuse of fiber is positively correlated with the dust blocking efficiency, that is, the thinner the fiber, the higher the dust blocking efficiency.
2. The composition and structure of the filter material
The organization structure of the filter material is related to the manufacturing process of the filter material. At present, the forming process of the synthetic fiber non-woven filter material mainly includes acupuncture method, direct injection method, bonding method, hot melt method, etc. The hot-melt injection molding method is mostly used, and in this method, two or more different fiber materials can be used for composite molding, which improves the efficiency of dust resistance, and is relatively soft and has good air permeability.
3. The chargeability of the filter material
The size of the filter belt classic two is positively correlated with the composition efficiency, that is, the greater the amount of static charge, the higher the dust resistance efficiency.
When dust passes through the filter material, the following happens:
(1) Collision retention: When the dust particle size is larger than the gap between the filter media fibers, the dust collides on the surface of the filter media, changes direction due to the reaction of inertia and force, and settles and adheres to the surface of the filter media.
(2) Hooking effect: There are burrs on the fiber. When the dust passes through the filter material, it is hooked by the burrs on the fiber to prevent the particles from penetrating.
(3) Multi-layer filtration: The filter material is made of superfine fibers lapped and woven into a net, and it has a multi-layered "three-dimensional structure". When the dust passes through the filter material, it is intercepted layer by layer.
(4) Electrostatic effect: The filter material is electrostatically charged, which repels quite polar dust particles, while it has an adsorption effect on dust particles of the opposite nature, that is, capture dust.