An important fiber in Patagonia's line, polyester allows them to build lightweight materials that dry quickly and can be used in a variety of applications, including trail-running tops and yoga tights. Polyester also blends well with natural fabrics like cotton. But virgin polyester is derived from petroleum, which comes at a high environmental cost.

Water repellency doesn’t just keep you comfortable, it keeps you alive. But for decades now, the coatings used in apparel to improve water-repellency have relied on per- or polyfluorinated chemicals, which contain fluorine and are most often referred to by their acronyms: PFCs, PFOAs or PFAS. This class of “forever chemicals” accumulates in air, water, food and even our bodies, and they raise serious health concerns, according to the Environmental Protection Agency.

Every textile Patagonia uses is the result of a complicated manufacturing process, making it difficult for them to evaluate all the raw materials, dyes and chemical auxiliary materials each of their suppliers use. bluesign® technologies, based in Switzerland, helps with this analysis, working at each step in the textile supply chain to assess and approve chemicals, processes, materials and products that are safe for the environment, workers and customers.