Holding sway for bamboo fabricsBy Isabel Berenguer Asuncion |Philippine Daily Inquirer
“GO GREEN with bamboo fiber!” screamed the tag attached to the pair of sweatpants I bought a few months back. “Lyocell” was the name of the “bamboo fiber” blended with cotton and lycra to make up the fabric of my new “environment-friendly” sweatpants. I was all too thrilled to have clothing made from bamboo! I’d always associated it with the nipa hut, furniture and tropical landscaping, but never with fabric.
Bamboo is the world’s tallest grass. It is highly self-renewing, grows very rapidly and absorbs five times more carbon while producing 35 percent more oxygen than a tree of the same size. Sounds like a good thing! But the use of bamboo fiber as a new “green” or “sustainable” fabric has not been without controversy.
Developed and patented by the Jiago Chemical Fiber Company in China, viscose bamboo fiber was first produced through a method similar to the production of rayon, a process that in essence, derives cellulose from the plant and produces a semisynthetic fiber. Cellulose can be derived from other plants as well. What this process entails is:
1 Mixing crushed bamboo in a solution of water with about 20 percent sodium hydroxide to break down the cellulose of the bamboo.
2 The solution is drained and the cellulose is pressed and the excess sodium hydroxide is drained, and the cellulose fiber is crushed and allowed to dry for a day.
3 Carbon disulfide is mixed into the fiber to cause it to gel, then sodium hydroxide is once again added to reduce the gel to a viscose solution, which is then forced through nozzles into a sulfuric acid solution to turn it into thread.
4 Fibers are drawn, washed and bleached until they are white, spun into yarn, and are ready for weaving!
5 The sodium hydroxide used in this process is also known as “caustic soda”, an ingredient in cleaning agents. In high concentrations, it is corrosive and can burn the skin. When inhaled, it can damage the respiratory passages. Carbon disulfide on the other hand was known to be a nerve poison. With ventilation it breaks down and diffuses but in higher concentrations, it can cause heart disease, brain damage, and other nervous system disorders. Both don’t sound very healthy nor environment-conscious.
I did some research and found out there are actually several types of fibers spun from bamboo: Bamboo Linen, “mechanically processed bamboo fiber” which is broken down using organic enzymes; Viscose Bamboo Fiber—like that of Jiago Chemical as the most common, most commercially viable way to produce bamboo fiber; and “Lyocell” bamboo viscose fiber, manufactured through a similar yet improved process, using natural enzymes over sodium hydroxide and caustic soda. My sweatpants’ fiber, yes!
Unfortunately, anything made out of bamboo is immediately marketed as being “green,” “environment-friendly” or “sustainable.” The awful truth is that most fabrics made from bamboo may not be as “green” as they make you think. Bamboo itself may be highly renewable, but the process to convert it to fiber and textile is arduous and requires methods that may not necessarily be sustainable. Neither is it essentially organic, since all the merits of being grown without being farmed nor fertilized is neutralized by the chemical process it has to go through. Bamboo Linen is the most “environment-friendly,” with Lyocell coming in second, being less chemically processed and yet commercially viable. The least natural would be the Viscose Bamboo Fiber which pioneered the use of bamboo cellulose for spun fiber.
In my industry, both types of fibers are already available for use as upholstery. Bamboo is known to have high tensile stress (difficult to tear the fiber from pulling) and it is interesting to see how that translates to durability. I’m also curious to see how it will withstand the bleaching effects of the UV rays of the sun, since its fibers are known to be porous and are supposed to be able to hold dyes and color pigments better.
Any new product deserves its day. While much controversy still surrounds bamboo fiber, its toughest moments are probably over.
Contact the author through email@example.com or through our Asuncion Berenguer Facebook account.