Why Durable Outdoor Fabric Waterproof?
It is very important to deal with changeable weather when traveling outdoors. However, I believe many people are not particularly clear about the two concepts of durable outdoor fabric waterproof and fabric anti splash. When facing the increasing number of outdoor brands claiming that their products have waterproof function, they will have some doubts, In the end, which durable outdoor fabrics are really waterproof? Why should the products that have adopted waterproof durable outdoor fabrics be treated with anti splash treatment? The article will give you a simple introduction to the difference.
Durable outdoor fabric waterproof usually refers to the waterproof function of the fabric itself. After the initial compact fabric and coated waterproof fabric, the waterproof fabric is now mainly pasted film fabric. The key to playing the waterproof role is the functional film used in durable outdoor fabric.
PTFE (polytetrafluoroethylene) films are basically used for pasting film fabrics that initially occupy the largest market share. This kind of film belongs to microporous membrane. The waterproof performance is expressed by the water pressure it can bear, which is not 100% waterproof. According to the European environmental protection research table, PTFE materials will produce compounds harmful to the environment during manufacturing, landfill and incineration. In recent years, there are more and more doubts about PTFE materials in the environmental protection community, and some countries began to restrict the use of PTFE materials. Landfill and incineration are the main domestic waste treatment methods in the world, and these two treatment methods will produce perfluorinated compounds when dealing with PTFE materials, and fluoride will pollute the atmosphere and land. Due to the long cycle of natural decomposition of fluoride, the environmental pollution caused by PTFE materials will be lasting and long. In contrast, another film adopted by more and more brands in recent years - nonporous hydrophilic membrane not only achieves 100% waterproof, making the waterproof performance of products more reliable, but also some nonporous hydrophilic membranes are favored by more people in the industry because of their environmental protection and harmless characteristics. The film is a molecular compound of polyether and polyester. It absolutely does not contain PTFE (polytetrafluoroethylene). It can directly contact the skin and is harmless to the body. It can be recycled like recycled PET plastic.
Generally, these durable outdoor fabric manufacturers with film technology do not directly sell films to clothing brands. They combine films with other materials and fabrics through the pasting process to form composite fabrics (as shown in the above figure, the middle layer is film). Brands can directly make waterproof clothing products by purchasing these composite fabrics. These fabrics used to compound with the film are not waterproof, such as polyester fiber and nylon. Therefore, when we wear waterproof clothes and encounter water drenching weather, we will see water seeping into the clothes, just like ordinary fabrics, but the inner layer of the clothes is dry and no water seeps in. This is the waterproof film in the middle of the composite fabric that plays a role.
What we see is that the water is dispersed into small droplets on the clothing and then slides down (as shown in the above figure) usually because the durable outdoor fabric is treated with anti splash treatment. Anti splash treatment is actually a special treatment covering the surface of durable outdoor fabric. DWR (durable water repellency) is usually added when the finished fabric is finalized, so as to obtain durable anti splash performance. The purpose of using DWR coating is that when water drips onto the clothing surface, it can form small droplets or directly slide from the clothing surface, so as to prevent the fabric from absorbing water. At the same time, it also makes the oil stain attached to the clothing surface easier to be removed. Most waterproof clothing adopts this DWR anti splashing treatment, and the advantage of DWR treatment is that the surface layer of clothing does not absorb water, so as to ensure that the waterproof fabric can achieve good air permeability, so that the human body has a very good wearing feeling.
DWR technology can be generally divided into two types: fluoride containing DWR and fluoride free DWR. Fluoride DWR refers to the surface treatment of DWR based on fluoropolymers, such as PFOA (ammonium perfluorooctanoate), which is widely used in the garment industry. Although it can provide high water splash, oil and pollution resistance, fluoride elements are not easy to degrade and can be soaked in heat and water, Ultraviolet and other factors are released into the water and atmosphere, causing harm to humans and other animals and plants. At present, scientists have found the existence of this compound in human and animal blood samples all over the world. Although there is no basis to point out the carcinogenic risk of PFOA and relevant regulations on PFOA restrictions so far, the German Federal Environment Agency (UBA) has proposed to include PFOA in the list of chemicals suspected of poisoning the reproductive system.