Wicking

What is wicking fabric?

Wicking is the same thing as “capillary action”.   OK, capillary action sounds even more complicated, but it’s not too complex.  First, I will give you the summary, and then I will give you a slightly more complicated explanation.

Simple definition of wicking: In regard to clothing, wicking moves moisture away from the body to the outer layer of the fabric so that it then has a better chance to evaporate away.  For cold weather activities, people often layer clothing.  The most inner layer should be a wicking material.  It would actually be good to have all layers having a wicking ability.  The purpose of the inner layer is to draw the sweat away from the skin to the next layers, which makes the wearer feel warmer and more comfortable.  The transfer of moisture happens due to capillary action, which we have explained is sometimes called wicking.  The fabrics used to draw moisture away are called wicking materials.  When moisture has moved from the skin into (nonabsorbent) clothing, it has more surface area and will evaporate faster.

Note: if you are wearing a few layers of clothing, the moisture may become trapped between layers if some of the layers are waterproof.  It is important for the layer closest to your skin is made of wicking material so that the moisture can at least move away from the body.

More Complicated Explanation:   Wiking or capillarity is the ability of a liquid to flow in narrow spaces without the assistance of, or even in opposition to, external forces like gravity. The effect can be seen in the drawing up of liquids between the hairs of a paint-brush, in a thin tube, in porous materials such as paper and plaster, in some non-porous materials such as sand and liquefied carbon fiber, or in a cell. It occurs because of intermolecular forces between the liquid and surrounding solid surfaces. If the diameter of the tube is sufficiently small, then the combination of surface tension (which is caused by cohesion within the liquid) and adhesive forces between the liquid and container wall act to lift the liquid.

Again, clothing is made with wicking fabrics to help draw off liquid from the wearers body by capillary action.

Moisture wicking fabric is a kind of fabric that is commonly used in workout clothing and sportswear because the material is designed to pull moisture away from the skin.  This will help keep athletes at a more appropriate body temperature and comfort.

Polyester and other synthetic fibers have superior wicking and therefore an ability to dry quickly.  Polyester clothes are naturally designed to bring sweat from the inner surface to the outer surface, thus leaving the skin dry.

Polyester, a synthetic material (man-made) that has a peculiar ability to pull moisture away from the skin to the exterior of the clothing. The key to this is the material’s hydrophobic, or ‘water-hating,’ chemical quality within the microfibers of the fabric. Essentially during exercise, the microfibers move sweat to drier areas, i.e. from the skin to the exterior of the clothing where it can evaporate more easily.

Cotton does not wick as well as polyester because cotton “absorbs” moisture.

Learn more about polyester on our polyester definition page.