What color umbrella should I support for shade in hot weather?

The black sun umbrella has a good sunscreen effect. Under the same conditions, the darker the color of the fabric, the better its ultraviolet resistance. In contrast, black, navy blue and dark green have better ultraviolet resistance than light blue, light pink and light yellow. In addition, when the umbrella is wet, due to the light conduction of water, the ultraviolet transmittance will increase and the protective effect will decrease accordingly. Therefore, wet umbrellas are not suitable for ultraviolet protection.