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Bast fibre has a long history of textile uses. Because of its inherent rot and abrasion resistance and high tensile strength,

the bast fibre long was used in products such as sails and ropes. Its cultivation requires no pesticides, nor irrigation

except in drought conditions, and it will grow in a range of geographical areas and climates. In recent years, as interest

heightened in organically grown fibres and eco-friendly production processes, hemp found a niche market in organic

apparel. Thanks to Naturally Advanced Technologies Inc. (NAT), Vancouver, Canada, who recently developed the CRAiLAR®

enzymatic technology for processing bast fibres in collaboration with National Research Council of Canada (NRC)

It is a patented process that treats bast fibre stock such as flax and hemp to

produce textile-grade fibres so comfortable and fine that they can be turned

into yarn suitable for hosiery, denim, knitwear, non-woven fabricsalone, or

blended with other natural fibres used to manufacture apparel products and

home furnishings.

Production of CRAiLAR fibre

CRAiLAR fibres begin as the long, strong filaments found in the outermost part of

the hemp or flax plant. CRAiLAR fibres are made from a portion of the plant stalk

that, because of its stiff hand and rough texture, has been historically underused

in the garment industry.

In the all-natural CRAiLAR technology process, long bast fibre is cut into 1.5- to 2-

inch staple lengths and processed in a closed-loop enzymatic bath using

specialised equipment to produce a soft, white fibre similar to organic cotton.

This softness of the fibre stock is achieved by removing all the lignin, the binding

agent which contributes to stiffness texture of bast fibre. The result is a fine, soft

and completely separated textile fibre that merges the strength and durability of

flax with the most desirable attributes of cotton and can be carded and spun on

traditional cotton spinning systems alone or blended with other fibres.

CRAiLAR advanced materials technology comprises a pulping process that does

not use harsh chemicals and is more economical than traditional pulping

equipment used in the craft industry. Further, the process maintains the integrity

of hemp's cellulosic structure and increases yield. Every step of this process can

be certified organic, making it eco-friendly from beginning to end.

What are the differences between hemp and flax?

Hemp and flax are both bast fibres. Hemp grows larger and its fibres are

coarser. Flax has very similar properties to hemp but produces finer fibres.

Hemp cultivation does not require the use of pesticides or herbicides; and it

flourishes in cool climates, is drought-tolerant, benefits the soil and supports

elimination of greenhouse gases. Flax is known to be easy to grow with minimal

use of herbicides, pesticides and engineered irrigation and is abundant in the

US and Canada, which significantly reduces costs from a supply-chain

perspective as compared to other natural fibres. The environmental

sustainability of flax is virtually identical to hemp with the exception that

hemp produces more biomass per acre than flax. However, the flax plant

generates a higher percentage of bast fibre per plant than hemp.

Initially, Naturally Advanced Technologies (NAT) developed hemp yarns

and fabrics with cotton like properties, and now they are using flax fibres

in the next phase of its CRAiLAR technology. The productivity of processing

using flax is said to be twice as efficient as it is with hemp, yielding

nearly twice as much usable fibre after going through the process. But

performance benefits of CRAiLAR flax fibre are the same or similar to

CRAiLAR hemp fibre.

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Fibre properties

CRAiLAR technology makes use of bast natural properties, including tensile strength,

thermoregulation, and antimicrobial and abrasion resistance. Its organic fibres are

stronger than glass and cotton fibres and softer as compare to linen fibre. The

organic fibres carry antimicrobial properties as well.

• Dye uptake – The ability of a fibre to absorb dye is critical, from both a cost and

an environmental standpoint. These organic fibres can achieve a better depth

of colour using 20 per cent less dye than cotton

• Shrink resistance – Fabrics made from these organic fibres shrink 50 per cent

less than cotton when laundered. Blended with other natural fibres, these organic

fibres act as stabilizers, helping garments retain their shape longer

• Staple length – CRAiLAR organic fibres start out as hemp fibres of upto a

metre long, which are cut to 75mm – comparable to the finest cotton in the

market. The longer the staple length, the softer the yarn and the finer the

gauge during knitting

• Tensile strength – Tensile strength refers to the amount of pulling a material

can stand before it stretches and breaks, and speaks to the longevity of a fabric.

These fibres take on the soft texture of organic cotton, but with a 40 per cent

highest tensile strength

• Thermoregulation – Garments made from the fibres retain bast’s thermo

regulation qualities. So, it keep the wearer comfortable in any kind of weather

• Wicking properties – The ability for a textile to disperse moisture along its

surface affects its absorbency and comfort. In laboratory tests, CRAiLAR organic

fibres was shown to have a wicking capability of 2.5 inches in three minutes, as

compared to the average of three inches in three minutes for other textiles

materials

Fabric produced using CRAiLAR technology resulted in a 50 per cent reduction in

shrinkage, 45-per cent increase in tensile strength, and 20 per cent reduction in

dye uptake. The fabric also exhibited wicking capabilities.

Comparison of properties with other fibres

CRAiLAR® flax is soft like cotton, has a similar colour, possesses similar

performance traits and is cool and comfortable to wear year-round, with the

strength, moisture-wicking properties and shrink-resistance of sturdy bast fibres.

This flax and cotton look the same, fit the same and wash the same. Still,

CRAiLAR® flax fibres shrink less than cotton fibres do, wick moisture better,

and have increased dye uptake meaning they take less chemicals to reach the

same colour levels.

Flax/Hemp fibre Organic fibre

Requires only regular rainfall Needs regular irrigation

Faster growing, high-yielding crop

Faster growing, high-yielding crop Top producing countries (India, Turkey, Syria,

Tanzania) located in warm climate

Flax is widely cultivated around the world. Widely cultivated around the world

Hemp has restrictions

Hardy. Shades out weeds and has fewer Requires more attentive cultivation. No or

natural insect enemies. No or little chemical little chemical fertilizer or pesticide input

fertilizer or pesticide input

Test fabrics (20 per cent CRAiLAR and 80 %

cotton yarns) used conventional cotton-

spinning equipment and existing infrastructure

with the following results:

• Reduced shrinkage 50 per cent

• Increase burst strength 45 per cent

• Reduced dye uptake 20 per cent

• Demonstrated wicking capabilities

Natural Non- Rene- Carbon No No No Organic Non Energy Soft Abso- Durable Breat- Shrink Colour- Recyc- Biode-

raw petroleum wable rich irrigation chemical chemical processing polluting efficient rbent hable resistant fast lable gradable

materials based fertilisers pesticides processing processing

CARiLAR

fibre

Organic

cotton

Conven-

tional

cotton

Conven-tional

hemp

Rayon

Linen

Wool

Silk

Acetate

Polyester

Nylon

APPAREL VIEWS / OCTOBER 201144

Soft, white CRAiLAR®

organic fibres can beblended with cotton fornumerous apparelapplications

Reduced environmental impact

Bast fibres has always been one of the most sustainable, renewable,

environmentally sounds crops in existence- requiring no irrigation, chemicals or

pesticides to thrive. While CRAiLAR® fibres are strong and durable like petroleum-

based synthetics they’re made from earth-friendly flax or hemp. The organic fibres

story is also green from beginning to end. The process is no polluting and consumes

a less energy and water than it makes to make other natural fibres or petroleum

based synthetic ones.

The processing chemicals used within the process have been approved for use

as textile auxiliary agents according to the Global Organic Textile Standards

(GOTS). GOTS approved inputs are screened for prohibited toxic chemicals

such as aromatic solvents, heavy metals or fluorocarbons as well as Genetically

Modified Organisms (GMO).

According to NAT, the CRAiLAR process can also be used with the stalk portion

of the oilseed flax plant, traditionally cultivated for food and industrial

applications, which would normally be discarded during processing. The company

adds that making use of this by-product, in addition to processing fibre-variety

flax, further enhances the sustainability factor. All of this makes CRAiLAR organic

fibres truly eco-desirable.

Uses and applications

Thanks to its ability to enhance the performance characteristics of natural bast

fibres, CRAiLAR is anticipated to gain adoption and use in textile, home furnishings,

industrial energy, medical and composite material applications.

It can be used in both mainstream and alternative apparel and fashion fabrics.

Potential applications for CRAiLAR flax fibre include denim, work wear, sportswear,

knitwear, bed and bath, disposable drapes, and gowns.

Brands using CRAiLAR fibre products

• Levi Strauss & Co., San Francisco, is developing cotton/CRAiLAR flax denim and

non-denim fabrics and is testing blends containing upto 50 per cent CRAiLAR flax

CRAiLAR® flax fibre iscut to staple lengths thatcan be blended withcotton and spun ontraditional cottonspinning systems.

• Hanesbrands Inc. signed a 10-year supply agreement of the fibre

• Westex Inc., the premier manufacturer of flame resistant and arc rated protective

clothing fabrics, is also doing product development with the flax fibre. Westex

products used in electrical maintenance, electric and gas utilities, oil, gas,

petrochemical, chemical, military, and ferrous metals industries

• Cintas, leading uniform brand in the US, is also using the fibre for their product

categories as CRAiLAR flax fibre can increase durability and longevity of the

uniform due to the tensile strength of CRAiLAR. In addition, the fibre’s ability to

wick moisture provides users of Cintas uniforms a more comfortable uniform to

wear in hot summer months.

Conclusion

The recent run up in cotton prices has opened up opportunities to promote other

natural fibres for various textile and apparel uses. Flax is a cost-effective raw

material for fibre production. And new CRAiLAR/cotton-blend alternative has arrived

to help textile makers manage the unpredictability of weather-sensitive raw cotton

supply and oil price-dependent synthetic fibre costs.

These fibres are the foundation of the first truly sustainable yarn in the apparel

industry, and are poised to become the revolutionary next step in sustainable

fibres, providing an economically sustainable complement to cotton

By Vasant R Kothari, Assistant Professor, NIFT, Bangalore

(Author can be contacted @ www.vasantkothari.com)