What is the breathability of the fabric?

  • The ability of gas molecules to penetrate the fabric is called the breathability of the fabric, which reflects the most basic performance of the material itself. The professional field usually converts air permeability into air permeability, which is defined as: the amount of air passing through a unit area of a certain fabric in a unit of time under a certain pressure condition.

    In a popular sense, breathability affects the feeling and comfort of wearing fabrics, as well as the feelings of heat insulation, warmth, breathability and coolness. Especially in summer, we often hear people around us complaining that the clothes we wear are not breathable, and they will be stuffy and feel hotter and uncomfortable. This means that the material itself has a low air permeability.

    Cotton Shirt Fabric

    Next, E-SUN will introduce several factors that affect the breathability of fabrics:

    1. Fabric structure of the fabric

    It can be seen under the microscope that the fabric is arranged by hundreds of warp and weft yarns, and the number of warp and weft yarns per square meter is different, which also results in different types of fabrics, such as light cotton and raw cotton fabric. The air permeability of the fabric decreases as the density of warp and weft yarns increases. In a certain range, if the density and tightness of the warp and weft yarns decrease, the air permeability will increase.

    2. Fiber characteristics and thread structure

    Of course, the molecular structure of the subdivided warp and weft threads are all made up of fiber cells. Of course, the recovery of moisture in the fiber also has a great influence on air permeability. Good fiber molecules have good air permeability, and fabrics containing wool and animal fibers have a high moisture recovery rate, and will expand and contract under the influence of various external environments. This will reduce the breathability of the fabric. It's like buying expensive sweater brands. It is comfortable to wear in an air-conditioned room or in a dry environment, but will sweat a little in a hot or humid environment. I feel bored. Cotton is no exception, and we have a similar experience. When cotton gets damp, it becomes tighter and less breathable.

    At this time, most special-shaped fibers, or man-made fibers as people often say, show excellent air permeability. Everyone has a prejudice against man-made fibers. When we hear man-made fibers, they are usually inferior to natural fibers. Actually this is a bit vague. As long as man-made fibers meet environmental protection and health standards, long-term exposure will not cause harm to human skin, and the use effect will be better. Of course, not all man-made fibers have excellent air permeability. For example, ordinary polyester fabrics and single-hole fibers have poor air permeability.

    Another factor is that the shorter the fiber length of the same material, the higher the rigidity, the greater the barrier and channel changes, the worse the air permeability, the longer the silk fiber, the better the fiber interior. Therefore, the air permeability of silk satin fabric is much better than that of raw cotton fabric.

    3. Environmental conditions

    The temperature and humidity of the external environment are both important factors that affect the performance of textiles. Textiles in warm areas will be too warm but lack of breathability. If we wear them to cold areas, there will be no warmth at all, which also shows the fact.

    Because when the relative humidity is constant, the air permeability of light cotton fabric increases as the ambient temperature increases. This is because when the ambient temperature rises, on the other hand, the thermal motion of gas molecules becomes stronger, resulting in increased molecular diffusion and permeability. On the other hand, the overall thermal expansion of the fabric improves the air permeability of the fabric.

    4. Conditions of Use

    The reason is simple. A windproof and water-proof fabric must have poor air permeability. For example, jackets, mountaineering suits, down jackets, or some workwear fabrics suitable for special occasions. The skin function of these materials is to keep warm, so generally the surface of the fabric will have a layer of windproof film or a layer of windproof lining inside. However, in order to maintain comfortable and breathable performance of underwear and other underwear, their fabrics have better breathability. So the fabric of the clothes also depends on its purpose.

    After reading the four points introduced above, I believe you will have a certain understanding of the breathability of fabrics. E-SUN is a well-known silk fabric suppliers. We provide all kinds of silk satin fabric. In addition, we also provide light cotton, raw cotton fabric, There are more products we suggest you visit our product page to learn more!