Principle of waterproof vent

In the state of water vapor, the water particles are very small. According to the principle of capillary motion, they can smoothly penetrate into the capillary to the other side (in our product, it can smoothly pass through the middle plastic layer), so that the phenomenon of vapor permeation occurs. When the water vapor condenses into water droplets, the particles become larger. Due to the surface tension of the water droplets (the water molecules "pull and compete with each other"), the water molecules cannot smoothly escape from the water droplets and penetrate to the other side, which is to prevent the The permeation of water occurs, making the vapor permeable membrane waterproof.