In the characteristics of modern outerwear for outdoor activities and sports, the expression «membrane fabric» or «membrane» is quite common. It is a very thin polymer film with microscopic pores. The structure of the membrane is such that these pores have a special shape, which provides the material with one-sided water permeability.. On one side of the membrane, moisture passes through, but on the other, it does not. Due to these properties, the membrane is used in the production of membrane fabrics, from which tourist and sportswear is sewn.
The composition of the membrane is a kind of sandwich made of a special film and fabric, as well as a material that protects the membrane from damage. The waterproof side of this film faces the inside of the garment, while the water-repellent side faces the outside. For hiking and sports, there is not only a clothing membrane. Modern camping equipment actively uses this special film. Also, climbing and trekking shoes, etc. are made from it.
The use of membrane fabrics in clothing solves the problems of comfortable stay in the fresh air. After all, actively moving a person sweats and this moisture should go outside. This prevents overheating and hypothermia. And the membrane fabric provides the necessary comfort in that its pores, facing the body, remove moisture from under the clothes. At the same time, the functions of the membrane are such that water cannot penetrate through it from the outside and, for example, a jacket with a membrane becomes waterproof during rain. Another useful property of the membrane is that it perfectly protects against strong winds and thus heat loss can be significantly reduced. In addition, the winter membrane is equipped with additional zippered openings to avoid overheating of the body during sudden warming.
The most famous brand of membrane clothing is Gore-tex from WLGORE & Associates. The most popular membranes are Gore-tex 2-Layer Laminates or Gore-tex Direct Laminate. The other two most powerful manufacturers of membrane fabric are the German company Vaude and the American BHA. But they also have a joint product — eVent.