Almost all Merino sheep's wool is processed in order to remove the characteristic scales from the wool, which make the sheep's wool itchy. The result of the treatment is a smoother coat, but at the same time the properties of the wool deteriorate. For example, wool's ability to repel and transfer moisture is significantly reduced or completely removed.
The so-called Superwash method has two steps, depending on the method. In the first step, the fiber scales are smoothed using a chemical process. In the second step, the fiber is coated, often with plastic, so that it can be machine washed.
Responsible brands use sustainable methods, but according to research, up to 70-75%(1,2) of washable Merino wool products on the market are also covered with plastic to enhance production and soften the skin feel.