What does Superwash treated Wool mean?

People have been spinning wool fiber into yarn for thousands of years, and the hand wash care of these yarns have been long understood. Then along came the synthetic yarns and machine washable garments that fiercely competed with wool. In the 1950’s the wool industry developed a process by which wool could withstand machine washing and would not shrink.


This is what a wool fiber looks like under a microscope.  Under conditions of warm alkaline water (aka warm soapy water) with agitation, the scales on the shaft of the fiber become the “locking device” and the wool will shrink and felt.

Superwash Treatment

Several different anti-felting processes have been developed. The Kroy/Hercosett method is the most frequently used industrially. This is the process used for Ashland Bay Superwash treated products. First the scales are removed with chlorine and then a polymer resin is applied to smooth the fibers.


The other added advantages to the superwash treatment process is the improved dyeability of the wool and less pilling tendency.

What are your thought? Do you love or hate superwash?

For more information and images from: http://www.drpetry.de/fileadmin/user_upload/petry/pdfs/Lanazym_Wool.pdf