Silk filled comforters gain their lightweight warmth from the natural properties of silk floss, silk that has been processed and layered to produce an exceptionally soft and fluffy filling similar to a cotton ball. This is stretched and layered to form the inner core of the silk comforter. In the highest quality silk comforters, this entire process is done by hand to ensure the purest silk floss.
The process starts with the silk cocoon being soaked in water to loosen it and allow the silkworm to be removed. Several cocoons are then stretched over U-shaped brackets to form what will eventually become one of hundreds of layers of silk floss. Each of these U-shaped pieces of stretched silk is washed several times and re-stretched.
After a thorough cleaning and stretching, the silk pieces are hung to dry in the sun, and re-stretched on the U-bracket, for further softening and cleaning by hand.
Each piece is then loosened and stretched into a small square...
...which is then stretched to the size of an entire comforter:
Forming the final silk floss filling, which is sewed into the center of the duvet.
Images and videos copyright Suzhou Shengkung Silk Co., used with permission.