By what method is white hotel linen generally whitened?

Whitening with fluorescent whitening agent: change invisible ultraviolet rays into blue or purple visible light, increase the reflectivity of fabric, and give people a clean and pure white feeling. Fluorescent whitening agent is a kind of coating, which has affinity with fiber, so it has good fastness and whitening effect.

The commonly used fluorescent whitening agent is VBL: it is used for cellulose fiber and light yellow powder, but it is not suitable for simultaneous use with anionic surfactants.