During the mercerisation (Soft-Lustre) process, with the use of Chlorine the scale structure of each wool fibre is removed, resulting in each wool fibre having a smoother surface. This smoothing of the surface of the wool fibres leads to an increase in the amount of specular reflection which causes the wool to take on asilk-like glossy appearance.
To enhance the hand feel (Softness) of the wool, during the last stage of the process, a very small amount of a silicone based polymer is applied which coats each wool fibre. Although the process has negligible effect on changing the actual micron of the wool, the perceived improvement in hand feel is the equivalent of using wool fibre which is around 2 microns finer in diameter.
In addition to significantly enhanced brightness and softness, the mercerisation (Soft-Lustre) process also renders the wool machine washable and can be used to make machine washable knitted products in accordance with Woolmark standards (Test Method 31).
Mercerised (Soft Lustre) treated wool is excellent for blending with fibres such as Cashmere, Mohair and Silk.