Weekly column by Barbara Hirsch
Some of our clothing is made with fabric that is both synthetic and natural. The fundamental substance is wood pulp, which is then synthesized through a chemical process. This process, of extruding filaments into thread from a highly viscous, or viscose solution of dissolved cellulose (also used to make cellophane before the advent of plastics), was first developed in the 19th century. The American Viscose Company began producing this material in 1910. The soft and shiny stuff was sometimes called artificial silk because of its similarities to the natural stuff, for which silk worms did the work, extruding their own viscous saliva.
Rayon became the common name and in recent years other varieties and trade names have emerged, such as Lyocell and Tencel, Modal, and Danufil. Bamboo based fabrics require the same processes in its manufacture. Environmentally speaking, these are unfriendly, even by the Federal Trade Commission’s standards, using “harsh chemicals that release hazardous air pollution.” Sodium hydroxide and carbon disulfide are two of these, with associated harmful effects on rayon workers and the factory environment. Lyocell and Tencel are preferred, as their process is less toxic and closed loop, meaning that the chemicals are recovered and reused rather than disposed of.
The methods and sustainability of growing and harvesting the wood for these fabrics is another factor. FSC cerified (Forest Stewardship Council) eucalyptus is used for Tencel, and as we’ve all heard, fast growing bamboo – most grown in China – can also be extremely sustainable, but perhaps it is better utilized in buildings and flutes, rather than in our t-shirts and sheets.