Waterproof and breathable fabric means that under a certain pressure, water can't penetrate into the fabric, but the sweat emitted by the human body can be conducted to the outside in the form of water vapor, so as to avoid the accumulation and condensation of sweat between the body surface and the fabric and maintain the comfort of wearing. It is a high-tech and unique functional fabric. Waterproofing is not a problem for the fabric industry. The key is how to achieve both ventilation and super wind resistance. Next, we will deeply interpret the new high-tech products from the types of fabrics that are waterproof, windproof and breathable.
First of all, air permeability is achieved by laminating waterproof and breathable films.
1 and PTFE film
The molecular diameter of water vapor is 0.0004 micron, the diameter of light fog with the smallest diameter in rain is 20 micron, and the diameter of Mao Mao rain is as high as 400 micron. If it can be made into a film with a pore size between water vapor and rain, it can be waterproof and breathable. Gore Company of the United States made use of PTFE to become the first company to produce this kind of film. After laminated with fabric, it is named GORE-TEX? (Golds TM) movies. After continuous efforts, the film was laminated with other hydrophilic films to form a composite film, and its fastness was greatly improved by special treatment of the film. It is generally believed that the water pressure of fabric can reach 10000mm, and the water pressure will drop obviously after washing for 6-7 times. The maximum air permeability can reach 10000g/sqm * 24 hours, but it is not only the fabric that can reach this value. It takes several washes to remove some glue, so the available pores increase and the air permeability increases. At the same time, the clothing made of this fabric can also block the invasion of cold air, prevent the wind from taking away the heat emitted by the body through the cloth, and make the body not feel cold because of the loss of heat; In addition, the fabric can resist 97.5% ultraviolet rays.
PTFE fabrics are mainly represented by Gore and Donaldson in the United States. Gore made his own films and composite materials, instead of selling films alone. He appointed a better clothing manufacturer to make clothes and had a separate salesperson to cooperate with him. After Gore produced a unique fabric with waterproof, windproof and breathable functions, it can be said that he wrote a myth in the outdoor field and was praised as "century fabric" in Europe and America. The clothes, shoes, hats and gloves made by Gore have been protecting American astronauts and countless explorers for many years. The fabrics have also been partially adopted by the armies of Germany, France, Nordic countries, South Korea, Singapore and other countries, and have been listed as 65,438 by Fortune magazine in the world. Almost all the world's top outdoor clothing brands adopt GORE-TEX? (Goldstetm) fabric provides comprehensive protection for outdoor enthusiasts and allows them to fully enjoy outdoor activities. Among them, the brands that China consumers are familiar with are: Arc' Teryx, The North Face, Black Yak, Ozark, Bonton, Garmont, ArcticFox, Nautica, Timberland, Tecnica, Vasque, Treksta and so on. In recent years, Gore has made continuous efforts to make GORE-TEX? (Galtes? ) The different functions and applicability of fabrics are accurately positioned, and four categories that can meet different outdoor sports needs are developed: GORE-TEX? Pro Shell、GORE-TEX？ Performance Shell、GORE-TEX？ Soft shell and GORE-TEX Paclite? Shell has established its absolute leading position in the functional fabric industry; Donaldson only produces films, which are compounded in the Japanese compound factory.
2.TPU movies
TPU is the abbreviation of thermoplastic polyurethane film, which belongs to non-porous hydrophilic film. Because the film itself has no pores, the waterproof effect is naturally good. Permeability is mainly achieved through its hydrophilic characteristics. Depending on the difference of steam pressure inside and outside the clothes, steam transfers from high pressure to low pressure, thus achieving the function of ventilation.
Second, air permeability is achieved through the coating.
Various coating agents with waterproof and breathable functions are coated on the fabric surface by dry direct coating, transfer coating, foam coating, phase inversion or wet coating (curing coating), so that the pores on the fabric surface are closed or reduced to some extent by the coating agents, thus obtaining waterproof performance. The permeability of fabric is obtained through the micropore structure formed on the coating by a special method or the interaction between hydrophilic groups in the coating agent and water molecules. Water molecules are adsorbed on the high humidity side through intermolecular forces such as hydrogen bonds, and then transferred to the low temperature side for analysis. Coated fabrics are widely used because of their low price and certain air permeability. However, due to poor waterproof and breathable performance and unsatisfactory hand feel, the market share is gradually decreasing.
The wet transfer coating fabric developed now makes the coating fabric glow with new brilliance. It not only has high physical indexes such as water resistance and air permeability, but also can be treated with 100% Teflon, and the washing fastness can reach more than 25 times, which makes it feel very good.
Third, air permeability is achieved through fibers.
1, Fante fabric. It was designed by the British Shirley Institute in the 1940s. It is made of Egyptian long-staple cotton with high count and low twist and pure cotton yarn with high density and thick weave. At first, it was mainly used for the cold-proof and immersion-resistant clothing of British air force pilots during World War II. When the fabric is dry, the gap between warp and weft is large, about 10 micron, which can provide a highly breathable structure; When rain or water wets the fabric, the cotton yarn expands, so that the gap between the yarns is reduced to 3 ~ 4 microns. This closed-cell mechanism is combined with special water-repellent finishing to ensure that the fabric will not be further infiltrated by rain. At present, this fabric has been replaced by other waterproof and breathable fabrics.
2.Coolmax fabric. Sweat is excreted by making pores on the fiber, which is a moisture-absorbing and sweat-wicking fabric on the market at present.
skill
The latest top category: GORE-TEX? Pro Shell three-layer material adopts the most advanced GORETM micro-grid backing new patented lining structure technology. First of all, the stitching marks at the seams of the clothes are obviously smaller and almost imperceptible, which greatly reduces the friction between the inner and outer clothes, which not only facilitates the free stretching of the body but also enhances the overall aesthetic feeling of the clothes; Secondly, compared with the previous fabrics, GORE-TEX? Pro Shell composite fabric can reduce weight by 1.5g per square centimeter, and the weight of the whole garment will be reduced by about 60g, which can make outdoor sports enthusiasts, such as mountain climbing, rock climbing, ice climbing, skiing and adventure, feel lasting protection and extreme comfort. With this special lining structure protection, GORE-TEX? The waterproof, windproof and breathable functions of Goldstetm membrane will last longer.