As part of the CFDA’s extensive Sustainability Initiatives Resource Hub launched in January 2019, the CFDA operated an A-Z directory called the Materials Index. The Index was designed as an informational tool, focused on fiber knowledge.

The Materials Index listings migrated in to the CFDA.com Materials Hub and split traditional fibers from new-age innovative fibers/materials.

This series of resource guides are dedicated to ensuring designers have extensive knowledge on traditional fibers.

FLAX (Linen)

Overview

Flax is a natural plant fiber. It is a bast fiber, which means it comes from the stem of a plant. Linen is made out of flax, though sometimes the term “linen” is used incorrectly to label fabrics of other fibers that have a similar look and feel.  While linen and flax are used interchangeably, flax can be found in other textiles as well, like lace and damasks. Flax is considered a more rare, high quality product and represents less than 1% of all textile fibers consumed worldwide.

In terms of sustainability, flax is often considered a preferred fiber with less harmful environmental impact.  Organic flax is one of the most sustainable fibers you can use according to multiple sources, including the Made-By Environmental Benchmark for Fibers (which gives non-organic linen a “C” rating, while organic linen gets an “A” – the best possible rating).  The cultivation of flax is the least water and energy intensive part of a linen garment’s lifecycle, while fiber extraction, material processing, and consumer use and care can have a much higher impact.

Two different kinds of flax are grown: flax for fiber, which is used to make linen textiles, and flax for seed, which is used to feed people and livestock.  The majority of flax for fiber is still produced in Western Europe (France is the world leader), though most of it travels to China for textile processing. While linen is often used in high quality household textile products (which are often referred to as “linens”), more than 70% of linen is used in the manufacture of clothing.

Flax is the oldest fiber known to have been used by humans. Humans have used it for cloth since at least 8,000 BCE. In 2009, archeologists (funded by the American School of Prehistoric Research at the Peabody Museum at Harvard University) discovered flax fibers more than 34,000 years old in a cave in the Republic of Georgia. Some of the fibers were twisted, indicating they were used to make ropes or strings, while others had been dyed using local plants.

Flax is a strong, durable fiber with a nice hand and body. It absorbs dye well and does not pill. Flax is similar to cotton chemically, but stronger, stiffer, more sunlight resistant, and faster drying. Flax has a high natural luster and is often marked by irregular fiber bundles and texture. The natural color of flax can range from beige to light grey. According to the CELC, linen is an intrinsically hypo-allergenic, anti-bacterial fabric with a soothing hand: inherent properties that have been known since the Middle Ages to help people with skin problems. Flax also has good thermo regulating properties, providing coolness in hot weather and warmth in cool weather.

Flax fibers range in length up to 90 cm, and average 12 to 16 microns in diameter, not as long as hemp (90 cm to 460 cm) but much longer than cotton fibers (which measure only as much as 3.5 cm). Longer flax fibers are used for high quality textiles, while shorter fibers are used for products with heavier yarns like kitchen towels, sails and canvas or in composites.

Fun fact: Did you know your U.S. dollar bill is 25% linen? (The other 75% is cotton.)

“Organic linen is grown without synthetic fungicides, pesticides and herbicides, in fields that are healthier for farmers, wildlife and surrounding communities. By 2020 all our linen will be organic.”  – Eileen Fisher

“Globally, less than 1% of linen is organically grown. For clothing companies, this means supplies of organic linen fiber are limited.  We are lucky enough to be able to buy fiber for our Organic Handkerchief Linen from Ludovic’s farms, but we only source 25% of our organic linen fiber from the EU. The balance, roughly 75%, is grown in China, a major organic linen supplier. China also dominates the linen yarn spinning industry. This means that Ludovic’s crop will be sent to China to be spun into yarn. Fabrics we weave in Europe—Washed Organic Linen Délavé is an example—all use linen yarn that is spun in China. What about the United States?

Flax for linen is not commonly grown in the US. But a different species of flax that is cultivated for its seeds is grown in the US. Flax seeds are used for food and linseed oil.”  – Eileen Fisher

Sustainability Considerations

Flax growing and cultivation has minimal environmental impacts – and can even be beneficial

• Flax is a renewable resource that is fast growing.
• Few, if any, chemical pesticides and fertilizers are required in the cultivation of flax. In fact, often flax comes close to the organic standard without trying. It requires significantly less fertilizers and pesticides than cotton, but slightly more than hemp.
• Flax cultivation does not require a lot of irrigation and in many cases is fed by natural rainfall alone.
• Flax is cultivated annually and has positive effects on eco-system diversity and offers a welcome environmental pause for soil quality, bio-diversity and landscapes, according to the Advisory Commission Report to the European Parliament, Brussels, May 20, 2008.
• Suggestions: Ideally, use Organic Certified Linen. If that isn’t possible, work together with your suppliers to ensure good practices since chemicals and excessive water are sometimes used, and soil erosion can occur if plants are pulled during harvest.

Retting can have harmful environmental impacts. 

• Retting refers to the process in which the natural fibers are separated from the stem of the flax plant.
• Chemical retting is frequently used due to its speed and control over uniform fiber quality. Chemical retting utilizes harmful chemicals and can cause further damage in the disposal of wastewater (rich in chemicals and harmful biological waste) if not properly treated.
• Water retting can use high large amounts of water and energy (to heat water), in addition to creating biological pollution. Even when retted in natural stagnant ponds or rivers biological pollution can be a problem.
• Suggestions: Dew retting is preferred in terms of sustainability, which requires no additional inputs of energy, water, or chemicals and allows nutrients to return to the soil through natural decomposition. If chemical or water retting are used, work with your suppliers to eliminate harmful chemicals, use renewable energy, clean and recycle water, and eliminate waste (especially toxic waste!).

Processing of flax can have harmful environmental impacts

• Processing of flax can include flattening the yarns with pressure to enhance natural luster, wet spinning, and the use of other treatments like softeners, wrinkle-resistors, dyes, bleaching and other finishes. This can involve using large volumes of water, energy (for things like boiling or heating in particular), and harmful chemicals.
• Suggestions: Avoid harmful chemicals and pollutants (refer to RSLs or organic standards), and if you have to use them make sure they cause no harm to workers or the environment, and that they are responsibly disposed of. Where water is involved: 1) try to reduce the amount needed, 2) recycle, and 3) clean wastewater (to either make it useful to be filtered back into your processing or safe if it becomes waste). Use less and better energy.

Flax Production is labor-intensive

• Production of flax fiber requires a lot of hand labor and should be closely monitored to ensure good, fair, and safe labor practices.
• Water, air, and environmental pollution (both chemical and biological) can not only harm the health of workers and people in communities near production, but impact their livelihoods by destroying local industries.
• Suggestions: Look for Fair Trade certified or transparent suppliers. Identify all people (aka stakeholders) impacted by the production of your product and make sure they are not harmed in the production of your product.

Potential impacts during customer use care

• The use stage of a linen garment can generates the most important environmental impact. According to a 2008 report for the European Confederation of Linen and Hemp (CELC), almost 80 per cent of linen’s energy and water consumption derives from washing and ironing the garment.
• In terms of consumer care, flax can be machine washed or dry cleaned. Because flax can wrinkle easily, pressing is often required.
• Suggestions: Design for machine or hand washing over dry cleaning. Can the design be beautiful without ironing? Be sure to educate your customers about best consumer care practices (wash less, in cold water, hang dry, etc.)

Flax is biodegradable, unless bad stuff is added to it

• Untreated flax is completely biodegradable. Things like dye, toxic chemicals, blended fibers and trims can hinder biodegradability.
• Suggestions: Design for optimal biodegradability. Be sure to educate your customers about how to dispose of the product, or even consider a company take-back program so you can re-use or properly dispose of the products you make.

More Sustainable Options

Look for linen that is:

• Certified Organic – You can search the GOTS Public Database to find certified vendors.
• Dew Retted – Which is better than water or chemical retting, but takes longer.
• Naturally Colored – Removing linen’s natural color and adding artificial color can have harmful environmental impacts, so try to use linen in its natural form. If color must be altered, opt for natural dyes and non-chlorine bleaches such as hydrogen peroxide, ozone bleaching (using ozone gas), or enzymes.
• Utilize sustainable design strategies

How It’s Made 

1. Growing: The flax plant is grown, generally in cool, humid climates and moist soil.
2. Harvesting: The flax plant reaches a perfect age (or ripeness) during which it must be harvested for the highest quality fiber. Pulling the fiber out of the ground is preferred to cutting the fiber for two reasons: 1) the fiber extends into the root and is shortened when cut, and 2) sap is lost when roots are cut, which diminishes the quality of linen. Flax stalks are often pulled out of the ground by hand, but there are some machines that do this as well.
3. Retting: The long fibers are extracted from under the bark in a process called retting. During this process, the woody bark is rotted away, loosening the gum that holds the fiber to the stem. This can be done three different ways. 1) Using natural moisture (called dew retting), where stalks are left in the fields or stagnant ponds to ferment for a couple of weeks. 2) Chemically, where stalks are placed in a solution either of alkali or oxalic acid, then pressurized and boiled. This method is easy to monitor and rather quick, although some believe that chemical retting adversely affects the color and strength of the fiber. 3) Mechanically, also known as vat or water retting, which involves soaking stems in vats of warm water (so rotting happens faster than natural retting) and crushing fibers between rollers to remove unwanted bark and gum.
4. Drying, breaking, and scutching: After stalks have been rinsed and dried, the woody portion is removed and most fibers are separated from each other. This can be achieved by crushing the plants between rollers in a process called scutching. Alternatively, plants can be pulled through beds of nails in a process called hackling.
5. Combing and straightening: In preparation for spinning, fibers are combed to remove short and irregular fibers, separating fibers by quality.
6. Cottonizing: might take place, which is the process of cutting a bast fiber to a length similar to cotton, allowing the fibers to be processed on equipment used for cotton.
7. Spinning: Multiple long linen fibers are combined together and twisted to form a yarn, which are put on bobbins or spools, ready to be woven into fabric. High quality linen requires a warm, humid environment for optimal spinning, and is often passed through a hot water bath (wet spun).

Available Standards & Certifications

Global Organic Textile Standard (GOTS) | The Global Organic Textile Standard (GOTS) is recognized as the world’s leading standard for textiles made from organic fibers. GOTS covers textile processing, manufacturing, packaging, labeling, exportation, importation and distribution. It does not cover the cultivation of the plant, which is covered by governmental organic standards like the USDA or

USDA ORGANIC | Raw natural fibers, such as cotton, wool, and flax are agricultural products and are covered under the NOP crop and livestock production standards – specifically National Organic Program (NOP) Regulation, 7 CFR Part 205.  The NOP regulations do not include specific processing or manufacturing standards for textile products, these are covered by the Global Organic Textile Standard (GOTS) .  However, any textile product produced in full compliance with the NOP regulations may be labeled as NOP certified organic and display the USDA organic seal. The NOP does not restrict the use of the term “organic” in the labeling of textile products that are certified under third-party certification bodies as long as all of the fibers identified as “organic” meet NOP standards. Textile products that are produced in accordance with GOTS may be sold as organic in the U.S. but may not refer to NOP certification or display the USDA organic seal.

MASTERS OF LINEN ® | MASTERS OF LINEN® is a registered mark and sign of excellence for linen 100% Made in EUROPE, from field to yarn to fabric. A benchmark for both the trade and the consumer. It is administered by the CELC.

Organizations & Working Groups

European Confederation of Flax and Hemp (CELC) | A European trade organization focused on all stages of production for linen & hemp.  They act as a spokesperson for 10,000 European companies (including spinners, weavers, brands, and more) and oversee the fiber’s development from plant to finished product. Created in 1951, the CELC conducts market analyses for the purpose of promoting the hemp and linen industries.

Suggested Reading

“Eileen Fisher on why she’s choosing organic linen”

“Eco-profile of a linen shirt” By Bio Intelligence Service

Linen, “the oldest textile of the world”, is considered as an environmentally friendly material. But is this image justified? This brief analysis looks at the environmental impacts generated by a linen shirt through a Life Cycle Analysis (LCA) and compares it to a cotton shirt.

Other Resources

This video demonstrates linen production on an industrial scale:

“How Linen Is Made” from Kravet

This video demonstrates linen production on a small scale:

“LINEN – Making Linen Fabric from Flax Seed – Demonstration Of How Linen Is Made” from Monreagh Centre

Bibliography

• Fashion Fibers: Designing for Sustainability by Annie Gullingsrud
• Textiles textbook by Sara Kadolph
• The Textile Exchange Preferred Fiber Materials Market Report
• MADE-BY Environmental Benchmark for Fibres
• Common Objective (CO) Linen Fiber Briefing
• European Confederation of Flax and Hemp (CELC)
• O Ecotextiles on Linen