Bamboo textiles are cloth, yarn, and clothing made out of bamboo fibres. While historically used only for structural elements, such as bustles and the ribs of corsets, in recent years a range of technologies have been developed allowing bamboo fibre to be used in a wide range of textile and fashion applications. Modern bamboo clothing is clothing made from either 100% bamboo yarn or a blend of bamboo and cotton yarn. The bamboo yarn can also be blended with other textile fibres such as hemp or even spandex.
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In China and Japan, thin strips of bamboo were woven together into hats and shoes. One particular design of bamboo hats was associated with rural life, being worn almost universally by farmers and fishermen in order to protect their heads from the sun.[1]
In the West, bamboo, alongside other components such as whalebone and steel wire, was sometimes used as a structural component in corsets, bustles and other types of structural elements used in fashionable women's dresses.[2]
Recent technologies have allowed cellulose processed from bamboo to be spun into viscose yarn.[3] Modern bamboo yarn is therefore a regenerated cellulose fibre. One such technology was filed in 2003 as US patent 7313906 by inventors Xiangqi Zhou, Zheng Liu, Liming Liu, and Hao Geng developed one such method of turning bamboo into yarn, creating new uses for bamboo in clothing.
The steps in the manufacturing of bamboo viscose are as follows:
1) Bamboo leaves and the soft, inner pith from the hard bamboo trunk are extracted using a steaming process and then mechanically crushed
2) The crushed bamboo is soaked in sodium hydroxide to produce cellulose. A common misconception is that sodium hydroxide is a harmful chemical . If used in a responsible manner sodium hydroxide has little known effect on the environment and health of workers. It is routinely used in the processing of organic cotton into fibre and is approved by the Global Organic Textile Standards (GOTS) and the Soil Association [4] Sodium hydroxide does not remain as a residue on clothing as it easily washes away and can be neutralised to harmless and non-toxic sodium sulphate salt. A chemical used in this step that can cause nervous system damage with chronic exposure is carbon disulfide.[5] If handled properly there are no negative side effects for humans and environment as sulphur containing by products can easily be transformed into sulphuric acid which is needed for the spinning process.
3) The bamboo cellulose is forced through spinneret nozzles (like a sieve) into a sulphuric acid bath that hardens the solution into viscose fibre threads and neutralizes the caustic sodium hydroxide to form Glauber's salt, sodium sulphate, which is used e.g. as a filler in lessive detergents. The process is the standard viscose process. This process is also used to manufacture fibres from wood pulp.
4) The fibre threads are spun into viscose yarn and rolled onto spools. According to textile classification so called bamboo is standard viscose, abbreviation CV. It has no advantages with respect to standard viscose made from wood pulp like e.g. beech or eucalyptus.
The processing of the cellulose pulp into fibre "can" be cleaner than the processing used for conventional viscose "if" a closed loop process captures and reclaims all the solvents used in the manufacturing, though this is "not" standard practice.[5]New processes stress enviromental purity and is under constant observation to confirm non pollution. The resulting bamboo viscose fibre is very soft to the touch.
The Swiss company Litrax [6] is one company involved in the manufacturing of bamboo fibre. Litrax claims to use a more natural way of processing the bamboo into fibre. In this the woody part of the bamboo is crushed mechanically before a natural enzyme retting and washing process is used to break down the walls and extract the bamboo fibre. This bast fibre is then spun into yarn.[7] In fine counts the yarn has a silky touch . The same manufacturing process is used to produce linen fabric from flax or hemp. Bamboo fabric made from this process is sometimes called bamboo linen. The natural processing of litrax bamboo allows the fibre to remain strong to produce an extremely high quality product. This process gives a material that is very durable.
Most of the bamboo used to make bamboo fibre and bamboo clothing is grown in China by Hebei Jigao Chemical Fiber Company [8] They hold the patent on the process for turning bamboo into fibre. This facility produces all of the bamboo viscose on the market. The bamboo is certified organic by OCIA (The Organic Crop Improvement Association) [9] To strictly control the quality of raw material, Hebei Jigao Chemical Fiber Company has built its own bamboo plantation in Sichuan Province, China, and keeps strict control over it. The bamboo is grown in accordance to the international organic standard of OCIA/IFOAM and the USDA National Organic Program, so as to ensure each bamboo stalk is of 100% natural growth and without any chemical pesticides. The proof of the ecologically sound methods behind bamboo production is the fact that all of the fibre produced at the facility in China is Oeko-Tex 100 certified [10] This certifies that the finished fibre has been tested for any chemicals that may be harmful to a person’s health and has been found to contain no trace chemicals that pose any health threat whatsoever. This means that every company working with bamboo starts with the same raw material and that this material is not contaminated.
Bamboo has many advantages over cotton as a raw material for textiles. Reaching up to 35 metres tall, bamboos are the largest members of the grass family [11] They are the fastest growing woody plants in the world. One Japanese species has been recorded as growing over 1 metre in a day [12] There are over 1600 species of bamboo [13] found in diverse climates from cold mountains to hot tropical regions. About 40 million hectares of the earth is covered with bamboo, mostly in Asia [14] The high growth rate of bamboo and the fact that bamboo can grow in such diverse climates makes the bamboo plant a sustainable and versatile resource. The bamboo species used for clothing is called Moso bamboo. Moso bamboo is the most important bamboo in China, where it covers about 3 million hectares (about 2% of the total Chinese forest area). It is the main species for bamboo timber and plays an important role for the ecological environment [15]
Once a new shoot emerges from the ground, the new cane will reach its full height in just 8–10 weeks. Each cane reaches maturity in 3–5 years. Bamboo can be continually re-harvested with no damage to the surrounding environment. It is a grass and so regenerates after being cut just like a lawn without the need for replanting. This regular harvesting is actually of benefit to the health of the plant – studies have shown that felling of canes leads to vigorous re-growth and an increase in the amount of biomass the next year [16]
Land use is of global importance as the world’s six billion people compete for water, food, fibre and shelter [17] Sustainable land use practices provide both economic and environmental advantages. Bamboo can be used as food, fibre and shelter and due to its ease of growth and extraordinary growth rate it is a cheap, sustainable and efficient crop. Bamboo grows very densely, its clumping nature enables a lot of it to be grown in a comparatively small area, easing pressure on land use. Yields of bamboo of up to 60 tonnes per hectare [18] greatly exceed the yield of 20 tonnes for most trees and only 1-2 tonnes per hectare for cotton [19] with a one-time planting for bamboo and little care and maintenance needed. In a time when land use is under enormous pressure, bamboo’s high yield per hectare becomes very significant.
Human activity is not only producing more carbon dioxide, but it is also severely damaging the ability of the planet to absorb carbon via its carbon sinks — the forests. Growing forests absorb CO2 but deforestation results in fewer trees to soak up rising levels of CO2. Bamboo minimises CO2 and generates up to 35% more oxygen than equivalent stands of trees [20] One hectare of bamboo sequesters 62 tonnes of carbon dioxide per year while one hectare of young forest only sequesters 15 tonnes of carbon dioxide per year [21]
Bamboo planting can slow deforestation, providing an alternative source of timber for the construction industry and cellulose fibre for the textile industry [22] It allows communities to turn away from the destruction of their native forests and to construct commercial bamboo plantations that can be selectively harvested annually without the destruction of the grove. Tree plantations have to be chopped down and terminated at harvest but bamboo keeps on growing [23] When a bamboo cane is cut down, it will produce another shoot and is ready for harvest again in as little as one year. Compare this to cotton – harvesting organic cotton requires the decimation of the entire crop causing bare soils to bake in the sun and release carbon dioxide into the atmosphere. Before replanting next years crop the cotton farmers till the fields which releases yet more CO2.[24]
Very little bamboo is irrigated and there is sound evidence that the water-use efficiency of bamboo is twice that of other trees [25] This makes bamboo more able to handle harsh weather conditions such as drought, flood and high temperatures. Compare bamboo to cotton which is a thirsty crop – it can take up to 20,000 litres of water to produce 1 kg of cotton and 73% of the global cotton harvest comes from irrigated land,[26][27] Some estimates indicate that cotton is the largest user of water among all agricultural commodities.
Yearly replanting of crops such as cotton leads to soil erosion. The extensive root system of bamboo and the fact that it is not uprooted during harvesting means bamboo actually helps preserve soil and prevent soil erosion. The bamboo plants root system creates an effective watershed, stitching the soil together along fragile river banks, deforested areas, and in places prone to mudslides. It also greatly reduces rain run-off [28] Conventional cotton-growing also causes a severe reduction in soil quality through the impact of constant use of pesticides on soil organisms.
As a natural product derived entirely from plant cellulose, bamboo fibre is biodegradable in soil by micro organisms and sunlight. [29] Having reached its useful life, clothing made from bamboo can be composted and disposed of in an organic and environmentally friendly manner. Synthetic fibres such as nylon and polyester are not biodegradable and remain in landfill for longer.
A huge benefit of using bamboo as the organic base for textile fibres is that there is no need for pesticides or fertilisers when growing bamboo. However, herbicide and fertilizer applications are common in some places to encourage edible shoot growth. Bamboo also contains a substance called bamboo-kun – an antimicrobial agent that gives the plant a natural resistance to pest and fungi infestation, though some pathogen problems do still exist in some bamboo plantations.[30] However, the finished bamboo fabric does not retain this antibacterial property; research is being conducted whereby antibacterial agents are being added to bamboo fabric to give it antibacterial properties.[31] For the moment the Federal Trade Commission (FTC) charge companies with fake antimicrobial claims. [32] Additionally, "raw bamboo fabric lets almost all damaging UV radiation pass through and reach the skin"; as such, research is being conducted to add UV absorbing chemicals to the fabric to prevent this from occurring.[31]
By contrast, only 2.4% of the world’s arable land is planted with cotton, yet cotton accounts for 24% of the world’s insecticide market and 11% of the sale of global pesticides.[33] Many of these pesticides are hazardous and toxic.
An estimated 1 million to 5 million cases of pesticide poisoning occur every year, resulting in 20,000 reported deaths among agricultural workers and at least 1 million requiring hospitalisation.[34] Even organic cotton farming uses pesticides – copper and copper salts.[35]
Fertilisers are also applied to cotton fields to increase growth rate and crop yields.