Plate No. 141 · fabric

Gore-Tex

Gore-Tex is not a woven cloth but a laminate, built around a thin microporous membrane of expanded PTFE, the stretched form of the same fluoropolymer as Teflon. The membrane's pores are too small for liquid water drops to pass but large enough for water vapor, so it is waterproof from the outside yet lets sweat escape, the trick called waterproof-breathable. Invented when Bob Gore stretched heated PTFE in 1969 and brought to market from 1976, it bonded to ordinary face fabrics and remade rain gear, mountaineering shells, and waterproof footwear.