News Home & Design Kapok Knot's Sleek Jackets Are Insulated With Plant Fiber It's an innovative, cruelty-free alternative to goose down. By Katherine Martinko Katherine Martinko Twitter Senior Editor University of Toronto Katherine Martinko is an expert in sustainable living. She holds a degree in English Literature and History from the University of Toronto. Learn about our editorial process Published November 3, 2020 07:52AM EST Kapok Knot Harrington jacket. Kapok Knot Share Twitter Pinterest Email News Environment Business & Policy Science Animals Home & Design Current Events Treehugger Voices If you're looking for a way to stay warm this winter without relying on goose down insulation, Kapok Knot is a good brand to check out. This Japanese outerwear company uses fibers from the kapok tree to create a warm filling that is said to be equivalent to goose down and significantly warmer than pure polyester insulation. Kapok trees, also known as Java cotton, are grown in Indonesia and produce seed pods with fluffy fibers. The fibers, which have a fill power of 579, have hollow cores that "efficiently regulate heat and wick away moisture while weighing far less than cotton and poultry feathers." Company founder Kishow Fukai told Treehugger, "Since kapok fibers are very light and short, it's difficult to form them into yarn. But after much research and development, I was able to form it into a sheet by blending it with polyester. The sheets are thin and not bulky, yet warm. We use recycled polyester to ensure that the sheets are as environmentally friendly as possible." The jacket insulation contains 40% kapok, 60% recycled polyester, and because it's pressed into a thin sheet, allows for a tailored appearance, rather than the puffy down jackets that currently dominate the market. Fukai says that the company is currently working on an all-kapok insulation: "We are currently doing more research to make it completely plant-based. Our goal is to deliver 100% kapok down jackets in the near future." Men's insulated dress coats by Kapok Knot. Kapok Knot In the past kapok has been used to stuff pillows and bedding, as well as flotation rings, thanks to water-resistant properties, but textile companies have largely avoided using it because it's hard to work with. The fibers are notoriously short, making it difficult to spin and turn into thread. But when that challenge can be overcome – as Kapok Knot has shown to be possible – it's a high-functioning, versatile fiber with potential to reduce demand for polyester fillings and goose down. The company prioritizes having a transparent supply chain. From its Indonesian farms where the kapok is grown, to Chinese facilities that blend the kapok with recycled polyester to make the sheets of insulation, to Japanese tailors who hand-sew each jacket, Kapok Knot says it "knows exactly where its clothing comes from, from the beginning to the end of the supply chain, treating everyone in the process with respect and dignity." Kapok Knot is Fukai's impressive attempt to clean up the fashion industry, which is responsible for roughly 10% of annual global carbon emissions. Fukai's family has been making apparel for four generations, so when he entered the business, he knew he wanted to reverse some of its inherent environmental damage. After discovering kapok in 2018, Fukai realized its potential as an eco-friendly material and launched two Kickstarter campaigns that met great success in Japan. Now established, Kapok Knot announced its U.S. debut in October 2020 and is now shipping its outerwear from Japan to American customers. You can see the range of coats and jackets available here. They range from sporty to dressy, for both men and women, and come in a number of classic colors.