Like nylon, polyester is an inexpensive polymer that can withstand wear. Polyester socks are more absorbent than nylon and have better breathability.
Polyester also has better and longer color fastness than cotton, and it dries quickly and does not absorb.
A: Polyester holds color better, so your socks won't fade as quickly.
A: Synthetic materials (plastic, nylon, polyester) do not breathe very well so they do not allow sweat to evaporate off your feet.