The Working Principle of Medical Mask Filter Material

The working principle of medical mask filter material
1. Diffusion deposition: The particle Brownian motion diffuses and displaces to the filter fiber, and is adsorbed by molecular gravity. Easy to capture small-scale particles, fine fibers and particles moving at low speeds.
2. Retention deposition: The larger particles moving with the airflow are retained by the mechanical sieving effect of the filter material. The ratio of particle diameter to the diameter of the membrane fibers affects interception efficiency.
3. Inertial deposition: When the particles pass through the curved mesh channel of the filter material, the particles break away from the airflow and hit the filter fiber due to inertia, and are trapped by molecular gravity. The retention effect is good when large particles, high density and high speed are used.
4. Electrostatic attraction deposition: The particles are deposited by the electrostatic action of the filter fibers.
The smaller the particle is, the stronger the deposition effect of 1 and 4 is, and the larger the particle is, the better the effect of 2 and 3 is, so it is not that the smaller the particle is, the more difficult it is to be filtered.
Based on the synergistic effect of various filtration mechanisms, the easy-to-penetrate particle size range of ordinary mechanical filter materials is 0.1m to 0.3m.
Medical masks are generally composed of the following materials:
Main filter material: such as polypropylene meltblown cloth, etc.
Other materials: metal (for nose clips), dyes, elastic materials (for mask straps), etc.
Medical masks generally have the following forms:
According to the shape of the mask, it can be divided into flat, duckbill, arched or foldable. According to the wearing method, it can be divided into ear-hook type, strap type or headband type.