What is coolmax fabric?

Coolmax is a specially engineered type of polyester fabric which is developed and marketed by Invista, an American textile corporation. Coolmax is the sole trademark of Invista. This type of polyester fabric is specially designed and engineered to keep users dry and comfortable. This means that this fabric can wick moisture via capillary action and also allow the heat to pass. Compared to other absorbent fibers such as cotton, coolmax absorbs little fluid and dries relatively quickly. Coolmax material is made from specially engineered dacron polyester fiber which is cationic dyeable polyester. The material is not hygroscopic; it does not have the tendency to absorb moisture, and has 20% higher surface area than traditional round fibers.

Coolmax fiber has a non-round cross-sectional area and compared to round cross sectional area the surface area is around 20 percent more. Since it is an engineered polyester hence compared to other polyester fabrics, Coolmax is flammable and has a relatively low melting point i.e. around 255 °C. Because of the low melting point, the application of coolmax is banned from certain high-fire-risk applications, such as firefighting and front-line combat. Coolmax fabric is used in a variety of applications, such as for socks, jeans, and other types of apparel.