Features of durable outdoor fabric
At present, the professional durable outdoor fabric on the market can be divided into riding clothes, assault clothes, etc. for example, riding clothes are mainly for riding and leisure sports, while assault clothes are mainly for alpine sports such as mountaineering and skiing. In addition to the requirements for participants' physical ability and skills, durable outdoor fabric is also required to adapt to bad weather and complex geographical environment, so as to ensure the personal safety of athletes. Therefore, outdoor sportswear fabrics are generally divided into riding clothes fabrics, assault clothes fabrics and other fabrics
Although there is no essential difference between durable outdoor fabric and home clothing, due to the two characteristics of outdoor and sports, the requirements for clothing are relatively strict and harsh: outdoor sports have high calorific value and more sweat evaporation, which requires good heat dissipation and air permeability of clothing. It is inevitable to encounter wind, rain, snow and fog in the field. Clothes should have certain waterproof performance. For outdoor sports, we hope to reduce the load as much as possible, and the clothes should be as light as possible. It is windy in the wild and cold in the mountains, so it is required to have high windproof and thermal insulation performance. Outdoor washing conditions are limited, and clothing has high requirements for antibacterial, deodorization and anti-fouling. For field operation, rock climbing and forest wearing, clothing requires good tensile and tear resistance... These performance requirements are very harsh from the perspective of textile technology, and even many indicators conflict with each other. Any single natural or chemical fiber can not meet these requirements, and these functions can only be achieved through the combination of multiple fibers and multi-channel chemical finishing.
1. Warmth retention
Although the warmth retention is closely related to the thickness of the fabric, the clothing is not allowed to be too heavy for outdoor sports. Therefore, it is necessary to keep warm and light to meet the special requirements of durable outdoor fabric. The most common method is to add special ceramic powders such as chromium oxide, magnesium oxide and zirconia into synthetic fiber spinning solution such as polyester, especially Nano fine ceramic powder. It can absorb visible light such as sunlight and convert it into heat energy. It can also reflect the far-infrared emitted by human body, so it has excellent heat preservation and heat storage performance. Of course, the far-infrared ceramic powder, adhesive and cross-linking agent can also be prepared into a finishing agent, and the woven fabric can be coated, dried and baked to make the nano ceramic powder adhere between the fabric surface and yarn. The finishing agent emits far infrared rays with a wavelength of 8 ~ 14 μ m. It also has health care functions such as bacteriostasis, deodorization and promoting blood circulation.
In addition, according to the bionic principle and referring to the structure of polar bear hair, the polyester fiber is made into a porous hollow shape inside, so that the fiber contains a lot of non circulating air, and the outside is made into a spiral curl shape to maintain fluffy, which can play a good heat preservation role on the premise of ensuring light texture. Of course, making clothes and even fabrics into double or even three layers to increase the number of non circulating air layers is also one of the most traditional heat preservation measures.
2. Water and moisture permeability
The sports meeting emits a lot of sweat, and it is inevitable to encounter wind and rain outdoors, which itself is a pair of contradictions: it should not only prevent rain and snow from soaking, but also discharge the sweat emitted by the body in time. Fortunately, the human body emits water vapor in the state of single molecule, while rain and snow are liquid water droplets in the state of aggregation, and their sizes are very different. In addition, the liquid water has a characteristic called surface tension, that is, the characteristic of gathering its own volume. The water we see on the lotus leaf is granular water droplets rather than flat water stains. This is because there is a layer of waxy hairy tissue on the surface of the lotus leaf, and the water droplets cannot diffuse and penetrate on this layer of waxy hairy due to the effect of surface tension. If you dissolve a drop of detergent or washing powder into the water droplets, because the detergent can greatly reduce the surface tension of the liquid, the water droplets will immediately disintegrate and spread on the lotus leaves.
Waterproof and moisture permeable clothing is to use the surface tension characteristics of water to apply a layer of PTFE chemical coating to the fabric to enhance the surface tension of the fabric, so that the water droplets can be tightened as much as possible without spreading and infiltrating the fabric surface, so that they can not penetrate the pores on the fabric. At the same time, the coating is porous, and the water vapor in the single molecule state can be successfully transmitted to the fabric surface through the capillary channels between the fibers.
After a large amount of exercise, if you stop to rest in the field, it may form water droplets in the inner layer of clothes because the external temperature is low and sweat cannot escape in time, which makes people feel very uncomfortable. This is the so-called "condensation" phenomenon. There is a special moisture permeable finishing process called "low condensation". It uses polyurethane (PU) and hydrophilic nano ceramic powder to finish the fabric. When the body evaporates a large amount of sweat, it can absorb too much sweat vapor, so as to avoid the phenomenon that the water vapor inside the clothes exceeds the saturated vapor pressure and turns into water droplets.
In addition to the fiber and coating, the fabric structure can also absorb moisture and sweat as much as possible. For example, the double-layer structure is adopted. The close fitting inner layer is made of hydrophobic fibers, while the outer layer is made of hydrophilic fibers. In this way, sweat can be transferred from the skin to the inner fiber by capillary action. Then, because the binding force between the outer hydrophilic fiber and water molecules is stronger than that of the inner hydrophobic fiber, water molecules are transferred from the inner layer of the fabric to the outer layer again, and finally emitted into the atmosphere.
3. Antibacterial and odor resistance
Due to the characteristics of exercise, sweat and sebaceous glands secrete a lot. In outdoor conditions, it is impossible to change clothes often. Under the appropriate temperature and humidity environment, microorganisms multiply in large numbers, resulting in an indecent smell and itching. Therefore, regular durable outdoor fabric are finished with antibacterial and deodorizing chemicals. Generally, the way of finishing is to fix organic quaternary amine and imidazoline surfactants or heavy metal ions such as silver and copper on the fiber through resin and crosslinking agent to make it have certain washing resistance. Of course, an important principle of choosing fungicides must be non-toxic or low toxicity, otherwise it is to abandon the basics and seek the end. In recent years, Japan has made many explorations in the research of natural antibacterial finishing agents, such as aloe, wormwood leaf, eucalyptus leaf, rose and other aromatic oil extracts with bactericidal effect, which are coated in porous organic microcapsules or porous ceramic powder, attached to the fabric, crosslinked and fixed by resin, through friction Backlog and other mechanical effects slowly release bactericide to achieve the purpose of durable antibacterial finishing. This kind of natural antibacterial agent is not only non-toxic and harmless, but also has certain health care function. It should be the development direction of antibacterial finishing. However, due to the limited means of fixing the antibacterial agent, the washing resistance of the antibacterial agent is not good enough. The antibacterial performance decreases every time it is washed, and generally disappears after dozens of times.
4. Antifouling and decontamination
Outdoor sports often walk and shuttle through the muddy and humid mountains and forests. It is inevitable to wipe clothes, which requires that the appearance of clothes should not be easily stained by stains, and once stained, it should be easy to wash and remove. The surface properties of the fiber are changed, the surface tension of the fabric is greatly improved, and it is difficult for oil and other stains to penetrate into the fabric. Slight stains can be removed by wiping with a wet cloth, and heavier stains are also easy to clean. Antifouling finishing can not only prevent oil pollution, but also has the performance of waterproof and moisture permeability. It is generally known as "three anti finishing" (waterproof, oil-proof and antifouling). It is a practical and effective advanced chemical finishing method, which is often used in the fabric finishing of outer clothing, backpacks, shoes and tents.
5. Antistatic and radiation proof finish
Mountaineering is the core content of outdoor sports. In addition to the original dense forests, the high mountains and plateaus above 3000 meters above sea level are generally dry due to low air pressure, easy volatilization of water, and durable outdoor fabric are basically made of chemical fiber fabrics, so the problem of static electricity is more prominent. The harm of static electricity generally shows that clothes are easy to fuzz and pilling, easy to be contaminated with dust and dirt, electric shock and stickiness close to the skin, and so on. If you carry precise electronic instruments such as electronic compass, altimeter and GPS navigator, you may be disturbed by static electricity of clothing and make mistakes, resulting in serious consequences.
Any object rubbing against each other may produce static electricity, but only dry insulating objects will accumulate static electricity and cause harm.
Therefore, the best antistatic fabric is of course made of natural fibers, but as mentioned earlier, pure natural fibers are not competent for the special requirements of outdoor sports, and even natural fibers will produce static electricity due to the lack of water molecules in a very dry environment. There are two main ways of antistatic finishing of fabrics: first, simply weave metal wires into the fabric to make conductive fabric (also electromagnetic wave shielding fabric and anti radiation fabric), so as to conduct and dissipate the static electricity generated by friction to the outside in time. However, this kind of fabric is not suitable for sportswear. The main reason is that it is not soft and comfortable enough. Another method is to use block polyether, polyacrylate and other antistatic agents with hygroscopic effect to coat the fabric surface with a chemical film that can adsorb water molecules, so as to form a continuous conductive water film on the fabric surface to dissipate the electrostatic conduction.
Due to the relative thinning of the atmosphere in high-altitude areas, the blocking and filtering effect on ultraviolet rays is greatly reduced, and the intensity of ultraviolet rays is much higher than that in low-altitude areas. Ultraviolet can effectively promote the production of vitamins and has bactericidal effect, but too strong irradiation will cause harm to human skin. The penetration of ultraviolet light is very strong, and the general fiber fabric can not completely shield its irradiation. By fixing nano-sized inorganic titanium dioxide (TiO2), nano zinc oxide (ZnO) and other UV shielding agents and organic salicylic acid series, cyanoacrylate series, benzophenone, benzotriazole and other UV absorbers on the fabric by resin crosslinking, it can play a certain role in radiation protection.
It can be said that durable outdoor fabric represents the latest cutting-edge technology in the development of textile science, which is also an important reason why a seemingly insignificant mountaineering suit and assault pants often cost hundreds, thousands or even thousands of yuan. Although the price is really not low, a set of professional durable outdoor fabric integrating windproof, breathable, moisture-proof, warm keeping, radiation protection and other properties may sometimes have the same meaning as life for a mountaineer! However, due to the diversity, complexity and unpredictability of outdoor sports, there may be many different requirements for the functions of clothing due to different environments and sports modes. Therefore, in terms of current science and technology, the overall performance of durable outdoor fabric is still difficult to be perfect.