The raw material of Tsumugi silk is silk remnants, featuring the characteristics of good breathability and strong drape like real silk, with a soft and full hand feel, and many fine cotton particles and fuzz on the surface. The formal writing of "油絲" should be "紬絲".

Silk floss or refined secondary cocoon silk floss is stretched and fluffed, hung on a bamboo spinning frame, and manually drawn into thread, or directly drawn into fine thread using an electric spinning machine, which is called "Tsumugi silk" or "Shi". This type of Tsumugi silk, with only slight twisting, is very soft. The fabric woven from it is called "Tsumugi fabric", with a unique texture and flavor, represented in Japan by Yūki Tsumugi and Kumejima Tsumugi. Additionally, there is "raw Tsumugi", which is half-refined to mimic the texture of ramie cloth.