If you want cool to wear summer pants, nothing beats rayon for breathing. I made some for a trip to a hot and humid area, it was the best thing I had packed. It was better than wearing nothing! They make some fabulous rayon batik fabric. Currently manufactured rayon is not the rayon of 30 years ago that was impossible to iron and get the wrinkles out. The "new" rayon drapes wonderfully and irons easier than most cottons. It is a natural fiber so preshrinking is recommended.