Why is the rain cloth waterproof?

Made of rain cloth (normal cotton cloth treated with water repellent). The water repellent is a paraffin emulsion slurry containing aluminum salts. After the paraffin is emulsified, it becomes fine particles, which are evenly distributed on the fibers of the cotton cloth. Paraffin and water are incompatible. When water encounters paraffin, it forms oval water droplets that roll around on paraffin. It can be seen that it is paraffin that plays a role in preventing rain. In physics, this phenomenon of impermeability is called“non-wetting phenomenon”. Once the water encounters ordinary cotton cloth, it penetrates through the capillaries between the fibers, which is called“infiltration phenomenon”. Double-sided waterproof, single-folded heat-sealed at four corners; ropes are fixed along the edges, covering recreational vehicles, trucks, boats, construction sites, firewood, and also trucks, trailers, equipment, ground, emergency rescue, painting, etc. . The product is waterproof, cold-proof, sun-proof, anti-aging, anti-ultraviolet, durable, pressure-resistant, folding-resistant, corrosion-resistant and lightweight. There is also a kind of rainproof cloth called waterproof Oxford cloth. Waterproof Oxford cloth is the waterproof effect of Oxford cloth by adding waterproof technology in the finishing. It is precisely because Oxford cloth has a waterproof effect, so it is also used in outdoor sports fabrics (backpacks, bags or trolley suitcases for clothing, simple tents, etc., professional tent fabrics for extreme environments such as mountains, plateaus, and snow-capped mountains) . Rainproof cloth Xiaobian thinks that as long as the fabric can be rainproof, it can be collectively referred to as rainproof cloth, right? But Xiaobian thinks that Oxford cloth cannot be said to be the strongest, but using Oxford cloth as a rainproof fabric, the lifespan is quite good Long, otherwise why do many customers ask to use oxford instead of other fabrics?