What kind of fabric is nylon? Does it have a sunscreen function?

Nylon is what we usually call nylon fabric.

No matter what kind of fabric, it has a certain sunscreen function. After all, it is a barrier, but it depends on the fabric's texture, color and whether it has been treated with sun protection. China requires that the sunscreen function should be at least UPF 40 or above, and the UVA should be less than 5%. Generally, light-colored ones will be worse.