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Textiles and ultimately clothing start with fibres

Know Your Fibres
Fibres are short fine hairs that can be twisted or spun into longer thread or yarn. This may be woven or knitted into fabric.
Fibres (and then yarns and ultimately fabrics) can be can be natural, synthetic or chemically produced hybrid called regenerated fibres.

Natural fibres Are derived from plants like cotton or animals like wool and silk, Coarse Fibres Are used for rope, string, sacking and industrial uses.Read more HERE
Fibres used for finer fabrics and yarn include cotton, wool and silk. Read more HERE
Synthetic fibres are man-made from chemicals many of which are petroleum derived. Read more HERE

Regenerated Fibres The base material is cellulose that can be obtained from a range of sources. It is then converted through a chemical process into fibres.
Yarns and Fabric
Fibres are then spun into yarns and threads. These often take the name from the fibre in which they are spun.
Threads can now be woven or knitted into fabric.
Fabric made from regenerated yarn often takes the name of the fibre such as bamboo or go under the trade name.

How Are Regenerated Fibres Made?

The base material is cellulose that can be obtained from a range of sources including wood, paper, cotton fiber, or  bamboo. It is then converted through a chemical process into a fiber. One such in bamboo. Most bamboo fabric  is made using  chemical solvents such as sodium hydroxide (NaOH – also known as caustic soda or lye) and carbon disulfide  combined with multi-phase bleaching. Both sodium hydroxide and carbon disulfide have been linked to serious health problems. Others are looking extremely promising and are biodegradable. But I don’t really know enough about them and

Regenerated Fibres Include
Rayon
Bamboo Rayon
Viscose
Modal
Tencel

Rayon Notes

Rayon or artificial silk is made from purified cellulose, derived from plants in this case primarily trees.
Because rayon is manufactured from naturally occurring polymers, it is considered a semi-synthetic or regenerated fiber.

The cellulose is harvested and then chemically converted into a soluble compound. The diluted liquid is forced through a spinneret to produce filaments.

These are now chemically solidified, resulting in synthetic fibers of nearly pure cellulose.

While the end products the process is concidered dirty and environmentally suspect. According to wiikipefia
Workers can be seriously harmed by the carbon disulfide used to make most rayon.
However there are many different types of rayon and some are greener than others.
Specific types of rayon include viscose, modal and lyocell, each of which differs in manufacturing process and properties of the finished product.

viscose rayon, which is rayon made using the viscose (cellulose xanthate) process.

Viscose is not a synthetic fiber made from petroleum; but rather it’s a “regenerated cellulosic fiber” made from cellulose – most commonly wood pulp, but many plants can be used, such as bamboo. The cellulose is broken down, and then “regenerated” into a fiber.

One of the major advantages of viscose over synthetics is that it is biodegradable.

Read more HERE

The following is information I am collecting on rayon. It is a highly technical product and quickly gets confusing. It is meant to be an introduction only .

 

It has been hard to find out wether Rayon is biodegradable or not!

 

There are definitely some  biodegradable rayons as made by Lenzing  which are touted as such. BUT most rayons are not described as biodegradable so I assume that other rayons may not biodegrade Or rather to be completely accurate like other synthetic polymers they will eventually biodegrade but may take hundreds of years to do so.
If by biodegrade you mean more like compostable then as far as I know, no rayon has ever been classed as compostable. However it is difficult to find hard, understandable data on this – at least I have not found any yet. If anyone knows anything about it I would love to know. So while it is easy to find out how long it takes for cotton to rot when scattered as litter there is no information on rayon.
Then there is this from  Wikkedpedia The more water-repellent the rayon-based fabric, the more slowly it will decompose.[10] Silverfish can eat rayon[citation needed]. Many kinds of marine creatures eat rayon fibers and it ends up in their bloodstream which can be fatal.[citation needed]
A recent ocean survey found that rayon contributed to 56.9% of the total fibers found in deep ocean areas, the rest being polyester, polyamides, acetate and acrylic.[11]
which suggests that rayon fibres act like other micro plastic fibres!

 

So while cellulose plastics used in packaging are often described as biodegradable, many rayons are not described as such. Could be an omission but is a grey area and until research proves otherwise, I will assume they are not.

 

Bamboo Rayon

 

Most bamboo fabric that is the current eco-fashion rage is chemically manufactured by “cooking” the bamboo leaves and woody shoots in strong chemical solvents such as sodium hydroxide (NaOH – also known as caustic soda or lye) and carbon disulfide in a process also known as hydrolysis alkalization combined with multi-phase bleaching. Both sodium hydroxide and carbon disulfide have been linked to serious health problems.  great article here

 

The big bamboo swindle

 

“As the Commission charges, even if the rayon used in the companies’ clothing and textile products is manufactured using bamboo as the cellulose source, rayon does not retain any natural antimicrobial properties of the bamboo plant. The rayon manufacturing process, which involves dissolving the plant source in harsh chemicals, eliminates any such natural properties of the bamboo plant. Similarly, the Commission charges that the companies’ clothing and textiles are not made using an environmentally friendly process.

 

The rayon manufacturing process uses toxic chemicals and results in the emission of hazardous air pollutants. And, despite the claims of Pure Bamboo and Bamboosa, the Commission charges that these rayon products are not biodegradable because they will not break down in a reasonably short time after customary disposal. Most clothing and textiles are disposed of either by recycling or sending to a landfill. Neither method results in quick biodegradation.”

 

Federal Trade Commission Report

 

Wether that means they will biodegrade in a compost heap but not in landfill,  I cannot say but the production of bamboo fibres isnt very green. Everyone seems to agree on 

 

Rainforest Alliance

 

The Rainforest Alliance has this to say about other forms of regenerated fibres

 

To make popular fabrics, including rayon and viscose, forests are cut down to make way for monocrop tree plantations. Trees from both the forest and the plantations are cut down and go through an incredibly toxic process to create what is known as dissolving pulp, a white fluffy material that gets spun into threads and woven into cloth.

 

This cloth is made into fabrics by some of the world’s most popular brands, including RAN’s Fashion Fifteen: Forest destruction for fabric has to stop. That’s why RAN has launched our Out of Fashion campaign, to demand the fashion industry commit to forest friendly fabric.

 

“But it still comes as a surprise to many to learn that some of the most common fabrics used by big name fashion brands — viscose, rayon and modal — also originate as trees in Indonesia, Canada, Brazil, and South Africa. Only now has a public conversation finally started about the fact that the forest fabric industry is causing human rights violations and forest destruction in some of the world’s most critical ecosystems.

 

Plantation expansion for pulp has also been devastating to indigenous and forest-dependent communities. Just in the area owned and operated by one company, Toba Pulp Lestari, in Northern Sumatra, a nonprofit organization called KSPPM has documented over 20 distinct cases where land traditionally owned by communities has been forcibly seized without the consent of the community and then clear cut for acacia plantations.

 

Lenzig & Greener, Biodegradable Rayon

 

Viscose, Modal and Tencel (lyocell), from Austria-based company Lenzing, are made from wood pulp. These high-purity cellulose fibres are obtained from sustainably managed forests, according to a report by the University of Cambridge’s sustainable manufacturing group. Compared with cotton, wood has the advantages of low water consumption, reduced pesticide use and produces up to 10 times the amount of cellulose per hectare, states the report. And these fibres are 100 per cent biodegradable.

 

Lenzing’s latest accomplishment in environmental fiber technology is known as Edelweiss. Edelweiss-technology is based on oxygen-based chemistry which is more eco-friendly than the conventional one. Thus Lenzing Modal® Edelweiss is the only Modal fiber which satisfies the highest environmental standards and is even CO2-neutral.

 

 

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