cuprammonium rayon

Cuprammonium rayon is a type of rayon, which is an artificial textile made from regenerated cellulose derived from plant sources. It was developed as a substitute for silk in the late 19th century and was the first man-made fiber.1

Cuprammonium rayon is specifically made by dissolving cellulose in a cuprammonium solution, which is a deep blue liquid containing copper salts and ammonia. This liquid is then squeezed through tiny holes to form fibers, which are then converted back into cellulose. This process was patented in 1890 by Louis-Henri Despeissis, building on the earlier discovery by Swiss chemist Matthias Eduard Schweizer. The German firm J.-P. Bemberg began producing this type of rayon, known as Bemberg silk, in 1908.231