The main functions of waterproof and breathable fabric are: waterproof, moisture permeable, breathable, insulation, warm. Its moisture permeability is 16000g per square meter every 24 hours, waterproof pressure can reach 8000-20000mm water column, insulation up to 100,000 volts. The fabric maintains its best performance even in harsh environments, accommodating temperatures from 427 degrees to minus 200 degrees. From the production process, the technical requirements of Waterproof Breathable Fabric are much higher than the general waterproof fabric; At the same time from the quality point of view, waterproof breathable fabric also has the functional characteristics that other waterproof fabrics do not have. Waterproof and breathable fabric not only strengthens the air tightness and water tightness of the fabric, but also its unique vapor permeability performance, which can make the water vapor inside the structure quickly discharged, avoid the structure breeding mold, and keep the human body dry all the time. It perfectly solves the problems of air permeability and wind proof, waterproof, warm and so on. It is a new type of healthy and environmental protection fabric. In the state of water vapor, the water particles are very small, according to the principle of capillary motion, can smoothly penetrate into the capillary to the other side, so as to occur steam permeability phenomenon. When water vapor condenses into water droplets, the particles become larger, due to the effect of water surface tension (water molecules between each other "pull and fight"), water molecules can not smoothly out of the water into the other side, that is to prevent the penetration of water, so that the vapor permeable film has a waterproof function.