There are two main reasons: one is incomplete bleaching, and the other is water quality.
The natural color of cotton is yellow, and the linen is bleached to white during the production process, but in the subsequent use process, continuous bleaching is required to maintain the white color.
Bleaching is divided into chlorine bleaching and oxygen bleaching. Oxygen bleaching is used more and more in China, and oxygen bleaching has higher requirements on temperature. If the specified temperature is not reached, the oxygen bleach cannot play its due role.
