New Processing Technology for Washable Sustainable Silk! “Yasa Silk” Makes Silk Easy to Wash at Home

 Nagahama, Shiga Prefecture is a silk fabric-producing city. The Hamachirimen Industrial Cooperative, a local organization, and the Northeastern Industrial Research Center of Shiga Prefecture have jointly developed Yasa Silk (patent pending). This silk processing technology defies the conventional wisdom that silk is easily damaged when washed with water. The main feature of Yasa Silk is that it is for already-woven fabric, not thread. The process treats silk fabric with organic compounds to strengthen the molecular bonds of the silk fibers, enhancing the durability and washing resistance of the fabric. Therefore, even 60 washes in a household washing machine cause hardly any abrasive wear,* shrinkage, or discoloration to Yasa Silk-processed silk fabric. (*Abrasive wear refers to fuzz on the surface of fiber damaged by friction, causing the surface to look whitish due to diffuse reflected light.)

 Yasa Silk makes silk fabric washable and sustainable. This technology enables you to wash your silk clothing at home to always enjoy it in a cleaned state while preserving the luster and feel that are unique to silk. “Yasa” for Yasa Silk comes from yasashii, a Japanese word meaning “easy” and “benign.” Yasa Silk-processed silk clothing is easy to care for and is also environmentally benign because it is durable and does not lose the silky texture after repeated washing. The name reflects a desire to contribute to society with silk fabrics that are benign to people, their skin, the environment, and everything else.

 Kazuo Yoshida, Chairperson of the Hamachirimen Industrial Cooperative, says, “Easy-to-wash silk fabrics are expected to be used for a wide variety of applications, including washable kimonos, outerwear, underwear, children’s clothing, women’s wear, nightclothes, bedding, and interior-related products.” The Cooperative will expand its commissioned processing business without limiting it to locally produced silk fabrics. The estimated processing cost is JPY1,500 to 3,000 per meter for a fabric with a width of 1.6 m.

 Furthermore, the Hamachirimen Industrial Cooperative will exhibit Yasa Silk at the 95th Tokyo International Gift Show Spring 2023, which will be being held at Tokyo Big Sight from Wednesday, February 15 to Friday, February 17, 2023. This participation is intended to disseminate information about Yasa Silk to companies from Japan and abroad to promote this technology for a wide range of applications, from apparel products, including washable kimonos and nightclothes, to bedding and interior-related products.