前面と背面の機能マスク異なります。たくさんのマスクs use a three-layer design type, in which the filter layer for filtering bacteria is located in the middle, the outer layer is a waterproof layer, and the inside is a water-absorbing layer. If it is worn backwards, the water-absorbing layer will become a waterproof layer, and the waterproof layer will become a water-absorbing layer, which will cause the saliva to adhere to the surface of the マスク, and the more it accumulates, the more the マスク濡れる可能性がありますマスクフィルタリング機能が失われます。