Flax linen

Flax is a fast and easy growing annual, which requires a cool and relatively humid climate.[1] In its growing and processing, flax has minimal impacts on the environment in comparison to other fibres. Linen, the fabric derived from the flax plant, may offer a more sustainable alternative to cotton and polyester. Humans began using flax for several thousand years ago, and flax is probably the first plant that was used for textile production. Natural fibers are divided into the plant fiber and animal fiber. Flax is a plant fiber, and along with cotton it is the most important ingredient in the industry of apparel and home textiles[?]. Plant fibers are divided into “seed hair”, stalk fiber, leaf fiber and fruit fiber. Flax is a bast fiber which means that the fiber is extracted from the stalk from the 0.5-1,25 m tall linen plant. The flax fibers located inside the stalk are joined together with plant glue to 60-75 cm long tows. The fibers can grow from the plants root to tip and is cemented in bundles of approximately 20-25 per stem. The fibers are similar to but straighter and often referred to as elements fibers. The flax is prepared by various processes such as scratching, digestion/rotting, fractioning, peeling, hedge treatment and sometimes even spinning and weaving. A distinction is made between flax and linseed/oil-lin.

Benefits

Flax is a good rotation crop, grows quickly and requires few chemical inputs in its cultivation.[1] Some sources state that flax production requires half the volume of pesticides per acre compared to that of conventional cotton.[2] In addition, flax is a rain fed crop and generally does not require irrigation.[3]

FAST-GROWING RENEWABLE FIBRES

FIBER	LENGTH	TIMING
Flax	1 meters	3-4 months [5]
Jute	1-4 meters [4]	3-4 months [6]
Hemp	4 meters	3 months [7]
Bamboo	24 meters	40 days [8]

Flax may be grown organically, and when claimed “organic” must meet the standard certification requirements by an internationally recognized certification agency accredited by International Federation of Agriculture Movements (IFOAM).

Flax fibre has a high natural luster and its natural colour ranges from beige to light tan to grey.[1]

Once the fibre is extracted from the stem, processing flax into yarn is largely mechanical, with minimal environmental impact.

Flax fibre and the resulting linen fabric have unique thermo-regulating properties, providing insulation in the winter and good breathability and a cool feeling in the summer.[1]

In 100% form, linen from flax fabric is biodegradable after its useful life, though absolute biodegradability depends on the dyes and trims used, and route of disposal.

Potential impacts

Cultivation

Flax does require herbicides to control weeds and, as a cellulosic fibre, it also requires some fertilizers. Synthetic fertilizers contain nitrogen salts which salinate the soil and over the long term decrease the productivity of the soil and pollute aquatic ecosystems.

Processing

Flax 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 bamboo for linen. 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.[9]

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 flax fibre is beige, and flax yarn or fabric 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.

Consumer care/washing

Linen (from flax) may be washed or dry-cleaned. Linen is durable to washed, but one should wash one’s linen more gentle than cotton so that the linen can maintain its luster and remain lint free. In order to not reduce the flax’s strength and durability one should rather wash at 60 degrees than at 95 degrees. Dirt loosens more easily from flax than cotton. Electricity and water use in the care of the garment can cause significant environmental impacts. Moreover, linen from flax wrinkles easily and requires heavy pressing to render it smooth after wash. This uses significant amounts of electrical energy over the long term.

End of use

Although 100% flax fibre is claimed to be biodegradable, the amount of time it could take for a flax 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.[10]

Availability

70% of the world’s crop is produced in Europe; 10,000 companies from 14 European Union countries cover all stages of the fibre’s production and transformation.12 Europe produces 1299 tonnes of European Flax® annually.[12] Dew retted linen from flax is readily available, though has to be specially requested. Certification on the retting method used should also be requested. Organic linen from flax is less available and more expensive than conventional linen from flax. Organic certification by an internationally recognized certification agency accredited by IFOAM must be in place.

Applications

In 100% fabrications, linen from flax is durable and available in a variety of yarn counts and fabric types. Suitable product applications include jeans, dress pants, jackets, dress shirts, handkerchief-weight blouses, knits, bed linens and outdoor fabrics. Blends of cotton/linen from flax are machine washable and suitable for sportswear, wovens and knits.

Optimize sustainability benefits

OPPORTUNITY	BENEFITS	CONSIDERATIONS
Promote suppliers using organic flax.	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 flax is not as readily available as conventional linen from flax, and commands a premium.
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 flax linen. Promote the particular aesthetic of ozone bleach effects.	Ozone can be used 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 the use of enzymes to strip out the natural beige colour of linen from flax. Promote the particular aesthetic of enzyme bleaches.		• Enzymes are not allowed in GOTS standards. • Enzymes 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 suppliers who use enzymatic retting over water or chemical retting..	Process is faster and leaves the water unharmed. Can be commercially reproduced.	• Low fibre strength. • Process is less common compared to other retting processes.
Promote the use of European Flax®.	Ensures that crop is rain fed, disallows use of GMO seed and ensures retting process does not pollute water.11	Enzymes are not allowed in GOTS standards. • Does not consider environmental impacts from dyeing, transportation, consumer care and disposal/end of use. • Not necessarily organic.
Actively seek out stain-resistant finishes for flax linen.	Will reduce washing, ironing and dry-cleaning by the consumer, and the water and pollution associated with consumer care.

Marketing opportunities

fast-growing natural resource
low water footprint in cultivation
organic If organic flax 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 flax,” 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.
European Flax® If European Flax is used.

Innovation opportunities

1. Use linen from flax 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% flax linen in stripes with cotton, then over-dye to achieve tonal colours without using chlorine bleach.

3. When used in 100% form, design “culturally durable” (i.e., styling that doesn't date with passing trends) products in linen from flax to optimize the fibre's physical durability.

4. Since linen from flax 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.

5. Create a flax product that is 100% biodegradable and compostable: the product can break down in a reasonable amount of time and is equipped with an ingredient that provides valuable nutrients to the soil after disposal.

6. Encourage handwashing or spot cleaning on the hangtag and labeling/POS to influence the consumer to take an active role in reducing environmental impacts of linen from flax garment/product care.

Sources

1. “Beginner’s Guide to Sustainable Fibres,” Textile Exchange, 201
2. “The Linen Shirt Eco Profile,” Bio Intelligence Service, February 2008. http://www.saneco.com/IMG/pdf/linen_shirt_eco-profile.pdf http://www.thehindubusinessline.com/industry-and-economy/agri-biz/govt-may-use-wastelands-for-tasar-silk-cultivation/article4479274.ece
3. mastersoflinen.com/en/
4. http://www.swicofil.com/products/003flax.html
5. http://www.decktowel.com/pages/how-linen-is-made-from-flax-to-fabric
6. http://www.fao.org/economic/futurefibres/fibres/jute/en/
7. http://www.hempage.de/cms/
8. http://www.resource-fibre.com/wp-content/uploads/RF_RFA_Founded_PR_0731121.pdf
9. http://www.ncsu.edu/bioresources/BioRes_06/BioRes_06_4_5260_Paridah_ASZ_Retting_Bast_Fibre_Quality_Review_1312.pdf
10. http://www.greenlivingtips.com/articles/waste-decomposition-rates.html
11. Ensures that crop is rain fed, and disallows use of GMO seed.
12. http://www.knittingindustry.com/uploads/2048/BE_LINEN_MAP_10-1.pdf

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