The filtration principles of medical masks are mainly divided into five aspects, though they are professional. However, only when we know its filtration principle can we better use medical masks.
(1) Brown movement: because the size of the particles is too small, it is easily impacted by other gas molecules, resulting in their motion trajectory is irregular Brown movement, and adsorbed on the surface of the fiber, the smaller the particle, the stronger the effect.
(2) the size of the interceptor particle is too large to penetrate the gap of the fiber, and then directly captured by the fiber surface. The bigger the particle size is, the better the effect is.
(3) inertial impact inertia is the continuous property of the motion of the particle itself. If the gas and the suspended particle impact the filter cloth or filter at the same velocity, the gas will change its flow direction with the hole in the filter, and the larger particle will continue to maintain its original flow direction because of the inertia, thus hitting the filter. On the material, the function of filtering is achieved. The bigger the mass and the faster the particle, the better the filtration effect.
(4) electrostatic attraction: because the fiber is charged, the fine particles are adsorbed on the surface of the fiber. The smaller the particle size and the lighter the particle is, the more attractive it is.
(5) sedimentation: the direct settlement caused by the gravity of the particles themselves is captured by the filter material; the greater the quality, the more opportunities.