What is cuprammonium rayon?

All the natural fibers are biodegradable in nature and hence after continuous use, the garments made from natural fibers are discarded. These discarded cotton garments can be used to produce a textile called Cuprammonium rayon. Sometimes, cuprammonium rayon is also referred to as ‘cupro’, ‘cupra’ or ‘ammonia silk’. Cuprammonium rayon is a type of regenerated cellulosic fiber. It is manufactured from cotton linter which is a short downy fiber that enfolds the cottonseed. This agricultural by-product is cellulose which is dissolved in cuprammonium solution.

In reality, cuprammonium rayon material was discovered in 1857 by Swiss chemist Matthias Eduard Schweizer. He found that the solution of copper salts and ammonia can dissolve cellulose which can then be extruded into regenerated material. But, this process of making fibers from cuprammonium solution was patented by a French chemist Louis-Henri Despeissis in 1890. The popularity of this material was reduced due to the presence of viscose rayon until in 1908 this material was started to be produced as Bemberg silk by a German textile firm called J.-P. Bemberg.

Cuprammonium rayon is a regenerated cellulosic fiber made from cotton linter pulp or wood pulp dissolved in cuprammonium solution. Cotton linter is the short downy fiber that enfolds the cottonseed; it is an agricultural by-product. Cuprammonium rayon is usually made into fine filaments that resemble silk or other luxurious fibers. It is often used in lightweight fabrications, sometimes in combination with cotton, to make textured fabrics with slubbed, uneven surfaces. Cuprammonium rayon may also be known as “cupro” or “cupra” and may be referred to as “ammonia silk.”

The raw material used in manufacturing cupro is cotton linter which is a natural fiber but after it is mixed with cuprammonium solution there is a drastic change in its structure. And the natural fiber is converted into regenerated fiber due to the presence of ammonia, copper, and caustic soda in cuprammonium solution. This is then made into fine filaments to resemble luxurious fibers like silk. Since cuprammonium rayon fibers do not have striations or markings hence they are often made into sheer and delicate fabrics like chiffons, satins, nets, etc.