Regarding the effectiveness of sun protection, upf 50 fabric is the best. UV resistant agent is usually added in the fabric finishing because of cost effectiveness. These fabrics are usually nylon fabric, polyamide fabric, polyester fabric.
Some fabrics are also sun proof naturally.
The best is alginate fiber. It is upf 50 and can resist 99.7% uv rays.
The second is hemp fiber. It is also upf 50 and shields 95% uv rays.
The third is bamboo fiber. It blocks 60% to 95% uv rays.
The last is cotton. It blocks 30% to 70% uv rays.
UVA and UVB rays are harmful to our skin. Get the best upf fabric for your clothing brands!