Bamboo linen

Bamboo linen is a natural fibre, and processing into yarn is largely mechanical with minimal environmental impact. Bamboo linen can be used as a sustainability choice that accentuates the many attributes of the bamboo plant.

Benefits

Bamboo is a “rapidly renewable” resource, meaning that it grows quickly and can be harvested at least once a year.[1]

FAST-GROWING RENEWABLE FIBRES

FIBER	LENGTH	TIMING
Bamboo	24 meters	40 days [1]
Hemp	4 meters	3 months [5]
Jute	1-4 meters	3-4 months [4]
Flax	1 meters [2]	3-4 months [3]

Bamboo linen has a natural ability to breathe and wick moisture away due to its porous nature. It keeps the wearer cooler—by one to two degrees—than someone wearing cotton. Bamboo is a biologically efficient, low maintenance crop that requires few chemical inputs during the growing season. It is mainly rain fed, and can grow in diverse climates. Due to its speedy growth and little input needed for growing, some say that using bamboo as an alternative to wood trees could help slow deforestation.[1] Once the fibre is extracted from the stem, processing bamboo into yarn for linen is largely mechanical, with minimal environmental impact. In 100% form, linen from bamboo fabric is biodegradable after its useful life, though absolute biodegradability depends on the dyes and trims used, and route of disposal.

Potential impacts

Processing

When processing for linen, bamboo is a bast fibre and is extracted directly from the stalk of the plant in a process similar to that used for jute, hemp and flax. The fibre is extracted through a process called retting, which separates the fibre from the stems using microorganisms and moisture. This is carried out in the field (as with dew retting) or in tanks (water or chemical retting). Dew retting is preferred as it utilizes the natural moisture of dew, but is the longest process, taking over 2–3 weeks to break down the stems slowly. Although chemical retting is the fastest process, the wastewater is concentrated and rich in chemicals and biological matter, which negatively impacts receiving water bodies, harming aquatic ecosystems, if left untreated before its release.[6]

RETTING PROCESS COMPARISION CHART [6]

TYPE	DESCRIPTION	ADVANTAGE	IMPACTS	DURATION
Dew Retting	Plant stems are cut or pulled out and left in the field to rot.	Returns nutrients back into the soil.	Reduced fibre strength; low and inconsistent quality; influenced by weather; and product is contaminated with soil.	2–3 weeks
Water Retting	Plant stems are immersed in water (rivers, ponds or tanks) and monitored frequently	Produces fibre of greater uniformity and higher quality.	Extensive stench and pollution arising from anaerobic bacterial fermentation of the plant; high cost; low-grade fibre. Requires water treatment maintenance.	7–14 days
Chemical Retting	Boiling and applying chemicals, normally sodium hydroxide, sodium benzoate, hydrogen peroxide.	More efficient and can produce clean and consistent long and smooth surface bast fibre within a short period of time.	Unfavorable colour; high processing cost. The wastewater is concentrated and rich in chemicals and biological matter, which negatively impacts receiving water bodies, harming aquatic ecosystems, if left untreated before its release.	60–75 minutes

Dyeing

The natural colour of bamboo fibre is golden, and bamboo for linen must be bleached with chlorine to render it light enough to receive dyes for light or clear shades. Chlorine bleach can form halogenated organic compounds in the wastewater. These compounds bioaccumulate in the food chain, are known teratogens and mutagens, are suspected human carcinogens and cause reproductive harm.

End of use

Although 100% linen from bamboo fabric is claimed to be biodegradable, the amount of time it could take for a product to decompose naturally and in a short period of time is dependent upon a number of conditions—including how much air, temperature and sunlight the fibre is exposed to. If the waste is buried in a landfill, it can take even longer for it to break down.[7]

Optimize sustainability benefits

OPPORTUNITY	BENEFITS	CONSIDERATIONS
Know the difference between natural bamboo linen fabric, and bamboo made from a viscose process.		Bamboo viscose is chemically processed and has greater pollution impacts to water and air.
Promote the use of linen from bamboo products.	Once the fibre is extracted from the stem, processing bamboo into yarn for linen is largely mechanical, with minimal environmental impact.
Promote suppliers using organic bamboo.	Ensures that no disallowed fertilizers are used.	Organic certification must be in place by a recognized international certification agency accredited by IFOAM. Organic linen from bamboo is not as readily available as conventional linen from flax.
Promote the use of natural colour.	No bleaches or dyes are used in this case, and associated pollution impacts are avoided.
Promote the use of non-chlorine bleaches, such as hydrogen peroxide, to lighten the natural beige colour for dyeing dark shades and bright/light shades.	Hydrogen peroxide harmlessly decomposes into water and oxygen gas.	Non-chlorine bleaches do not strip out the original colour of the fibre. Consequently, lighter and brighter colours will be duller due to the over-dyed effect. Non-chlorine bleaching is adequate for dark colours, which mask the original beige tone.
Promote the use of ozone bleaching processes to strip out the natural beige colour of linen (from flax). Promote the particular aesthetic of ozone bleach effects.	Ozone can used be with no water at all.	Ozone has limited availability, and is relatively expensive since it requires investment in ozone generating equipment. Ozone processes produce a different aesthetic than chlorine derivative or permanganate bleaching.
Promote suppliers who use dew retting over water or chemical retting.	Dew retting reduces the biological load in the receiving water bodies, and adds nutrients to the soil.	The natural colour may vary slightly from lot to lot, since the process is influenced by weather.
Promote the use of enzymes to strip out the natural beige colour of bamboo linen.		Enzymes are not allowed in GOTS standards. Enzymes produce a different aesthetic than chlorine derivative or permanganate bleaching.

Availability

Bamboo linen fabric is available from Deltracon in Belgium. This company produces a heavier quality bamboo linen fabric suitable for home furnishings. Expressing an interest in bamboo linen fabric to your suppliers can help to expand its availability worldwide.

Applications

Linen from bamboo fabrics are seen in both knits and wovens, and range from medium-weight jerseys to heavyweight wovens for trousers.

Marketing opportunities

bamboo linen Fabric should not be referred to simply as “bamboo,” since the processing of bamboo into linen and into rayon varies significantly. The bamboo textile should be referred to more specifically as “bamboo linen” or “viscose made from bamboo.” This should be done consistently on labeling, hangtags and POS.[8]
organic (if organic bamboo fibre is used) All fibres, yarn, trims and dyes used to manufacture the garment must comply with the GOTS organic garment standard. Simply state “made from 100% organic bamboo,” if this is verified and accurate.
biodegradable All fibres, yarns, trims and dyes used to manufacture the product or garment must also be biodegradable, or disassembled before disposal. This should be substantiated with documentation that the product can completely break down into non-toxic material by being processed in a facility where compost is accepted. Secondary label or marketing material should be provided to instruct customer.
non-chlorine bleached If alternative bleach is used.
dew retted If dew retted processed.
enzyme retted If enzyme retted processed.
fast-growing natural resource.
low water footprint in cultivation.

Innovation opportunities

1. Use linen from bamboo fibre in blends with cotton to achieve grey/beige heather effects, then over-dye the cotton side to achieve heathered colours without using chlorine bleach.

2. Use 100% bamboo linen in stripes with cotton, then over dye to achieve tonal colours without using chlorine bleach.

3. Since bamboo linen wrinkles easily, and washing and caring for the garment can cause significant environmental impacts, design garments that utilize the natural wrinkling of the fabric as a design feature to influence the customer to reduce ironing of the final product and the energy it uses.

4. Create a bamboo linen product that is 100% biodegradable and compostable: the product can break down in a reasonable amount of time and can provide valuable nutrients to the soil after disposal.

5. Encourage handwashing or spot cleaning on the hangtag and labeling/POS to influence the consumer to take an active role in reducing environmental impacts.

Sources

1. voanews.com/content/a-13-2006-08-29-voa51/323110.html
2. https://www.hempage.de/cms/
3. decktowel.com/pages/how-linen-is-made-from-flax-to-fabric
4. swicofil.com/products/003flax.html
5. fao.org/economic/futurefibres/fibres/jute/en/
6. https://www.ncsu.edu/bioresources/BioRes_06/BioRes_06_4_5260_Paridah_ASZ_Retting_Bast_Fibre_Quality_Review_1312.pdf
7. https://www.greenlivingtips.com/articles/waste-decomposition-rates.html
8. business.ftc.gov/documents/alt172-how-avoid-bamboozling-your-customers
9. Other: www.nrdc.org/international/cleanbydesign/files/CBD_FibreFacts_Bamboo.pdf