For the filter material of a good protective mask, the following three conditions should be met. One is that the filter efficiency is high when the mask is in good contact with the user's face, the other is low breathing resistance, and the third is that the user feels comfortable. There are many kinds of materials for the filter materials of dust-proof masks, including ordinary fabrics, animal hair, and non-woven fabrics. Very popular in the national standard is an activated carbon felt material.

The structure of a gauze mask has poor adhesion to the human face. Many small particles that are extremely harmful to us will enter the respiratory tract to the lungs through the gap between the mask and the face. The filter material is generally some mechanical fabric. The only way to achieve high dust blocking efficiency is to increase the thickness, and the negative effect of increasing the thickness is to make the user feel that the breathing resistance is great and uncomfortable. The electrostatically treated non-woven fabric can not only block large dust particles, but also the electrostatic charge attached to its surface can absorb fine dust through electrostatic attraction, achieving high dust blocking efficiency. The thickness of the filter material is very thin, which greatly reduces the user's breathing resistance and feels comfortable, thus achieving the three necessary conditions for a good filter material as we mentioned earlier. With a good filter material and a scientifically designed mask structure, an efficient and high-quality mask is formed.