Sun umbrellas are actually a replica of umbrellas. The biggest difference from traditional umbrellas is that sun umbrellas use anti-ultraviolet umbrellas, which are mainly used for umbrellas. The general umbrella is made of ordinary waterproof fabric. Therefore, judging whether a sun umbrella can be used as an umbrella is mainly determined by the fabric of the sun umbrella. At present, most sun umbrellas can be used as umbrellas.
According to the national "Assessment of Anti-ultraviolet Performance of Textiles", only UPF (ultraviolet protection factor value) greater than 30 and UVA (long wave ultraviolet) transmittance less than 5% can be called anti-ultraviolet products. The protection level standard is "UPF30+". When the UPF is greater than 50, it indicates that the product has excellent UV protection performance, and the protection level is marked as "UPF50+". "However, the UPF of UV protection umbrellas on the market is generally only between 30 and 40.
Among many fabrics, fabrics with a thick umbrella surface have better UV resistance than thin ones. Generally speaking, cotton, silk, nylon, viscose and other fabrics have poor UV protection, while polyester is better; therefore, most of the sun Umbrellas are mainly made of polyester fabric, and polyester fabric is also the main fabric for making ordinary umbrellas. Therefore, most sun umbrellas can be used as umbrellas.
In addition, there are many silver gel anti-ultraviolet sun umbrellas on the market. The special coating of this kind of sun umbrella does have sun protection function, but because the "film" is relatively delicate, it is easy to change color and fall off under sun exposure, and the corrosive effect of rain is also It will lose sun protection and have a short service life, so it is not suitable for use as an umbrella. Therefore, if the sun umbrella you buy is a silver glue sun umbrella and the silver glue is applied to the outside of the umbrella, it is recommended that you do not use it as an umbrella.