In addition to being blocked by fibers, the dust can also be blocked by the dust captured in advance. Therefore, the dust on the surface of the fiber is loosely accumulated in a "dendritic structure", the fiber is "dry" and the dust is "branches". There are many fibers and can be formed. There are more dendritic structures, more dust per unit area, and longer service life of the filter. There are more fibers, and the space between the fibers is small, and the dendritic structure formed by the dust is firm, and the dust collection is blown away. The possibility of secondary pollution is small.

Two pieces of filter material with the same thickness and the same bulkiness, the fine fiber filter material has high filtration efficiency, and the fine fiber filter material has a large dust holding capacity. The same efficiency, the same structure, two pieces of filter material composed of different fibers, the resistance of the fine fiber filter material low.

The filter can capture any form of particulate matter, including liquid droplets. The filter material is soft, porous, and somewhat attenuating. The filter produces resistance to the airflow and has some flow sharing effect. However, the filter can not be used at any time When used as a water baffle, it cannot be used as a shield or a wind deflector.

The filter screen carries water, and the dust on the top is mixed with water to form a mud. If the filter material is dense filter paper or filter cloth, the mud will quickly paste the filter screen. For the relatively fluffy filter material, after absorbing water, it has been captured Dust may enter the lower wind end of the filter with water droplets, and once it dries, the dust will fly again. Sometimes, the water on the filter is not serious enough to drip, but the trace moisture is enough to transport the dust on the windward side of the filter to the leeward side After the filter is air-dried, there is a risk of dust re-spraying. The filter only deals with dust. It has no multi-functional obligation and no multi-functional ability.