Percale cotton
Percale cotton is a fine cotton fabric with plain weave.
It means that the weft and the warp are worked in a 1 to 1 ratio and that their threads are therefore perfectly perpendicular.
Medium weight, percale cotton is made from fine, tightly woven yarns: the finer the thread the more precious, soft and light the fabric will be.
Percale is also used for summer sheets for the feeling of freshness it can give.