Bamboo: Some facts behind the fiber
In part because of its luxurious softness, smooth hand, flowing and gentle drape, and easy price – at least compared with silk and cashmere – and eco friendly cachet, bamboo has gained entry throughout the fashion industry. But it has been the trumpets heralding bamboo as the latest and hottest sustainable eco-fabric that have been the most strident. And some of the hoopla is justified. Growing bamboo is a wonderfully beneficial plant for the planet and most is naturally organic bamboo.
Botanically categorized as a grass and not a tree, bamboo just might be the world’s most sustainable resource. It is the fastest growing grass and can shoot up a yard or more a day. Bamboo reaches maturity quickly and is ready for harvesting in about 4 years. Bamboo does not require replanting after harvesting because its vast root network continually sprouts new shoots which almost zoom up while you watch them, pulling in sunlight and greenhouse gases and converting them to new green growth. And bamboo does this the natural way without the need for petroleum-guzzling tractors and poisonous pesticides and fertilizers.
Bamboo the plant is wonderfully sustainable; bamboo the fabric isn’t so easy to categorize. There are two ways to process bamboo to make the plant into a fabric: mechanically or chemically. The mechanical way is by crushing the woody parts of the bamboo plant and then use natural enzymes to break the bamboo walls into a mushy mass so that the natural fibers can be mechanically combed out and spun into yarn. This is essentially the same eco-friendly manufacturing process used to produce linen fabric from flax or hemp. Bamboo fabric made from this process is sometimes called bamboo linen. Very little bamboo linen is manufactured for clothing because it is more labor intensive and costly.
Newer manufacturing facilities have begun using other technologies to chemically manufacture bamboo fiber that are more benign and eco-friendly. The chemical manufacturing process used to produce lyocell from wood cellulose can be modified to use bamboo cellulose.This lyocell processing is substantially healthier and more eco-friendly because N-methylmorpholine-N-oxide is supposedly non-toxic to humans and the chemical manufacturing processes are closed-loop so 99.5% of the chemicals used during the processing are captured and recycled to be used again. Only trace amounts escape into the atmosphere or into waste waters and waste products.
Other chemical manufacturing processes for bamboo fabric are appearing such as using acetic anhydride and acetic acid with sulfuric acid as a catalyst to form acetate fiber which is then spun into a yarn.
New nano-technologies are also being introduced into the bamboo clothing industry. GreenYarn, a new startup located in Boston, is developing a bamboo clothing line made from nano-particles of bamboo charcoal. GreenYarn’s “Eco-fabric” is manufactured from 4 to 5 year old Taiwanese-grown bamboo that has been dried and burned in 800 degree C ovens until it is reduced to charcoal. The bamboo is processed – we don’t know how – into fine nano particles which are then embedded into cotton, polyester or nylon fibers. This conventional fiber yarn that contains trapped bamboo charcoal nano particles is then woven into fabrics … mostly socks and blankets now.
Greenyarn’s Eco-fabric is promoted as being anti-bacterial, anti-fungal, anti-static, de-odorizing, breathable, thermal regulating (cool in hot weather and warm in cool weather), and environmentally friendly. Obviously, a significant part of Eco-fabric’s claims to sustainability depend upon the sustainability of the original cotton, polyester or nylon fibers that have been impregnated with the bamboo charcoal nano particles. In a footnote, Greenyarn mentions that the active bamboo charcoal ingredients will only remain active in the clothing for about six months of active use.
Chemically-manufactured bamboo rayon has some wonderful properties which are adored by conventional and eco-aware designers and consumers:
- Bamboo fabric has a natural sheen and softness that feels and drapes like silk but is less expensive and more durable.
- Bamboo clothing is easy to launder in a clothes washer and dryer.
- Because of the smooth and round structure of its fibers, bamboo clothing is soft and non-irritating, even to sensitive skin. Some people with chemical sensitivities can not tolerate bamboo clothing. We are not sure if this intolerance is due to the intrinsic nature of bamboo but it more likely because of other chemicals added or used during the manufacturing and finishing processes of the clothing.
- Bamboo is naturally anti-bacterial and anti-fungal supposedly because of a bacteriostatis agent unique to bamboo plants called “bamboo kun” which also helps bamboo resist harboring odors. “Kun” is also sometimes spelled “kunh”. The bamboo kun in bamboo fabric stops odor-producing bacteria from growing and spreading in the bamboo cloth allowing bamboo clothing to be more hygienic and to remain fresher smelling.
- Bamboo clothing is hypoallergenic.
- Bamboo is highly absorbent and wicks water away from the body 3 to 4 times faster than cotton. In warm, humid and sweaty weather, bamboo clothing helps keep the wearer drier, cooler and more comfortable and doesn’t stick to the skin.
- The structure of bamboo fibers make bamboo fabrics more breathable and thermal regulating than cotton, hemp, wool or synthetic fabrics.
- Bamboo clothing is naturally more wrinkle-resistant than cotton, and while it might still require ironing after washing, bamboo fabric can be ironed at a lower temperature than cotton. Shrinkage during washing and drying is minimal at warm temperatures.
- Bamboo fibers and fabrics absorb dyes faster and more thoroughly than cotton, modal and viscose with better color clarity. Bamboo fabrics do not need to be mercerized to improve their luster and dye-ability like cotton requires.
- Designers such as Kate O’Connor use bamboo fabric as an eco-friendly replacement for silk. Speaking of bamboo eco-fashion, Kate O’Connor calls bamboo fashion “so much cheaper [than silk] and it’s really good for the environment.” “It is the perfect summer fabric” according to Kate O’Connor. Linda Loudermilk, another savvy eco-fashion designer, frequently incorporates bamboo into her eco-fashions. Amanda Shi ofAvita has some of the most exciting and originally beautiful eco-fashion in bamboo.
Bamboo the plant and also bamboo the fabric can rate high as an environmentally friendly and renewable resource:
- Bamboo grows rapidly and naturally without any pesticides, herbicides or fertilizers.
- Bamboo clothing (both mechanically and chemically manufactured) is 100% biodegradable and can be completely decomposed in the soil by micro-organisms and sunlight without decomposing into any pollutants such as methane gas which is commonly produced as a by-product of decomposition in landfills and dumps.
- Growing bamboo improves soil quality and helps rebuild eroded soil. The extensive root system of bamboo holds soil together, prevents soil erosion, and retains water in the watershed.
- Bamboo grows naturally without the need for agricultural tending and large diesel exhaust-spewing tractors to plant seeds and cultivate the soil.
- Bamboo plantations are large factories for photosynthesis which reduces greenhouse gases. Bamboo plants absorb about 5 times the amount of carbon dioxide (a primary greenhouse gas) and produces about 35% more oxygen than an equivalent stand of trees.
- Bamboo fabrics and clothing can be manufactured and produced without any chemical additives although eco-certification such as Oeko-Tex is necessary to insure that the manufacturing and finishing processes are healthy.
- Currently, there are no known genetically modified organisms (GMO) variants of bamboo. Let’s hope it stays that way.
Bamboo vs. Cotton
Cotton requires a large amount of pesticides to maintain growth. Bamboo does not and is naturally irrigated.
Bamboo owns a unique antimicrobial bio-agent called "bamboo kun." Textiles made of bamboo have natural antibacterial, antifungal and odor resistant properties, even after multiple washings. Cotton does not.
Bamboo fabric requires less dye than cotton, modal or viscose, and the color is much more vivid.
Bamboo fabrics are as soft as cashmere.
Bamboo fiber is a biodegradable textile material. As a natural cellulose fiber, it can be 100% biodegraded in soil by microorganisms and sunshine. The decomposition process doesn't cause any pollution to the environment.