Eco-conscious fashion houses, as well as sewing hobbyists, experiment with a wide range of materials to minimize the industry’s impact on our environment. Cupro fabric is one of those materials. It is a fine mix of both plant-based natural fibers and synthetic fibers.
Cupro has a soft silky texture that is skin-friendly. For eco-conscious consumers, the question remains: Is Cupro sustainable? What exactly is cupro fabric, and how is it made? Read on as we look at its environmental impact.
Cupro fabric, also known as cuprammonium rayon, is a regenerated cellulose fabric made from recycled cotton linter - the fluffy fiber around the plant’s seeds.
It gets its name from the copper and ammonium used in its production process. Cupro fabric may seem like a new fabric in sustainable fashion; however, this fabric goes way back to the 1890s when a French chemist, Dr. Max Fremery, obtained a patent for the cupro manufacturing process of mixing a cellulose solution with copper salts and ammonia. This was the birth of synthetic/ammonia silk in Germany.
Cupro fabric, sometimes also called ‘ammonia silk,’ is a semi-synthetic fabric made with recycled cotton linter from cotton production. These linter fibers are so tiny that manufacturers cannot spin them into conventional cotton. To make cupro, the recycled cotton linter is then exposed to ammonium and copper to create a new substance. This is where the cupro fabric gets the name cuprammonium rayon.
It is then mixed with caustic soda and squeezed out through a spinneret. The final processes involve washing out the copper, neutralizing the sulfuric acid, and weaving the linter into cupro fibers used to make cupro clothing1.
Other semi-synthetic fabrics include rayon, lyocell, modal, and so on. Manufacturers equally make these fabrics from plant-based materials (mostly wood pulp) and then treat them with chemical solutions.
If you can think of any silk clothing, there’s most likely a cupro fabric version in the market. Cuprammonium rayon is super soft and skin-friendly, making it suitable for a wide range of clothing - from blouses to dresses that drape nicely, nightgowns, lingerie, scarves, and so on. Manufacturers also use this semi-synthetic fiber for lining men’s suits, giving it that luxurious feeling on the skin.
You can also find cuprammonium rayon in winter coats and jackets. Its moisture-wicking properties also make it suitable for eco-friendly sweatpants and yoga clothes. The fabric is not very stretchy; however, Cupro blends well with other fabrics like spandex and elastane.
It also blends with natural fibers like organic cotton and semi-synthetic fibers like TENCEL.
And now the big question is - Is cupro sustainable? Well, the answer is yes and no. Cupro fabrics have their environmental pros and cons, which we will dive into shortly.
While producers derive cupro fibers from cotton waste which sounds like a great way to turn a cotton plant by-product into a usable fabric, the cupro production process isn’t as innocent as it seems.
Cuprammonium rayon is plant-based, meaning it is vegan and cruelty-free, unlike silk from silkworms. Cupro fabric is also machine washable, unlike silk which requires dry cleaning because of its delicate texture, making it more sustainable.
Manufacturers can use closed-loop processes to make the cupro fabric. This process involves recycling the chemical solutions a number of times and is more eco-friendly.
However, as with rayon-type fabrics, this semi-synthetic textile goes through a chemical-intensive process to create the fiber that manufacturers can weave into a cupro material. These chemicals include ammonia, copper sulfate, and caustic soda. These toxic chemicals are hazardous both to factory workers and the environment if not correctly disposed of.
China is the primary producer of cuprammonium rayon3. Sadly, China’s synthetic textile factories are sometimes unethical and can harbor modern-day slave labor. They export tons of cupro fabric to Western nations despite these human and environmental concerns.
Also, the production of cuprammonium has been banned in the United States because manufacturers have failed to follow essential air and water protection regulations.
So is the cupro fabric really sustainable? While this semi-synthetic textile derived from cotton is said to be eco-friendly, cruelty-free, and generally a vegan alternative to silk, its production is not ethical and sustainable.
When buying cupro fabric, you want to check that it was produced following ethical conditions. You can more reliably choose other fabrics like TENCEL as a sustainable alternative to silk. There are also more innovative cellulosic fibers made from orange fiber and seaweed that you can consider.
Due to environmental factors involved in producing cupro or cuprammonium rayon, the fabric is growing less prevalent in the market. However, there are other eco-friendly options you may want to consider
Made from the cellulose of beech trees, the modal fabric is a more robust version of rayon, similar to silk. Modal is very breathable and has similar properties to cotton. Modal is lightweight and has a beautiful drape. It also doesn’t lose its shape or shrink when washed. Modal is sustainable. However, this depends on the manufacturer. Lenzing, an Austrian company, sources most of its beech trees from local farms that employ sustainable methods. Modal also uses 70% less energy than cotton2.
The fashion industry uses modal for a wide range of clothing, including bath towels, bedsheets, undergarments, and so on.
Lyocell, also known as TENCEL, is a textile produced by Lenzing. The company further improves on semi-synthetic cellulose fibers of modal and rayon using nanotechnology to make lyocell fabric. The fabric can be easily manipulated and blends well with synthetic fibers like spandex. Lyocell is naturally hypoallergenic and sensitive to the skin.
Both cupro and cotton come from the same natural source - the cotton plant. However, these fabrics are very different regarding treatment and production. Cotton is a much more versatile fabric for a wide range of clothing, including undergarments, socks, and everyday outfits.
Cupro, on the other hand, goes through intense chemical processes where it gets dissolved in a viscous solution made of ammonia, copper, and caustic soda. In terms of energy, cupro production requires more energy than cotton.
Cotton, unless grown organically and sustainably, is also not a particularly environmentally friendly crop.
Cupro and silk are comparable. Cupro, commonly referred to as ammonia silk, appears to have a shinier look. Silk is associated with luxury and is used for a wide range of clothing, including dresses, shirts, lingerie, suits, and so on.
What distinguishes both fabrics is the raw material used. While silk is sourced from silkworms, cupro is a product of regenerated cellulose fibers from cotton linter, making them cruelty-free and vegan. Cupro is also machine washable, unlike silk which needs dry cleaning because of its delicate texture.
Both cupro and viscose come from cellulosic fibers from plants. While cupro comes from a cotton waste product, viscose comes from fibers from regenerative trees like bamboo, beeches, and so on. Cupro is much stronger than viscose in terms of durability and texture. This is because cotton fibers are much stronger.
Polyester is a synthetic fabric produced with fossil fuels. It is fast to produce and is much cheaper than most fabrics. Cupro has a much softer feel and drapes better than polyester. Cupro is semi-synthetic and biodegradable, unlike polyester, which can sit in landfills for many years. However, cupro is much more difficult to dye and requires more chemicals to complete the dying process.
Cupro has a moderate stretch, is lightweight, and has unique properties that make it breathable. However, it could shrink if not correctly cared for. Here’s how to care for your cupro fabric:
You may wash cupro fabric with a washing machine. However, you want to check the manufacturer’s instructions in case it's a mixed fabric.
If you are washing with a washing machine, ensure you set it to a gentle cycle. Use a mild detergent and cool water, and avoid hot water to prevent shrinkage. You also want to turn your cupro clothes inside out to avoid damage by other clothing, zippers, and buttons during the wash cycle. When done, lay the item flat and leave it to air dry. Avoid using an air dryer.
You can iron your cupro, but it should be set on the lowest temperature setting and ironed carefully. However, steaming it is the safest way to straighten out your cupro. Simply hover your iron around the fabric using the iron steam setting.
Here are a few brands using cupro today:
Girlfriend Collective offers a stylish range of t-shirts and vests made with a combination of cupro and organic cotton. The cupro used comes from a zero-waste facility located in Japan. They also make their clothing at an SA8000-certified factory in Hanoi.
Girlfriend Collective, a sustainable fashion brand, prioritizes and uses recycled materials like post-consumer water bottles, fabric scraps, deadstock, and other waste products. Their packaging also comes in recycled materials and is 100% recyclable.
Whimsy + Row offers beautiful blouses and dresses made from a blend of cupro and TENCEL. The brand recycles fabric scraps to make new pieces of clothing. They also claim to prioritize ethical production and work to ensure fair wages and safe working conditions.
Whimsy + Row is also a carbon neutral brand and offsets its carbon emissions with carbonfund.org.
Outerknown is a sustainable brand that offers a wide range of eco-friendly clothing. They offer 100% cupro women’s tops and also use cupro for their jacket linings.
Outerknown claims to have taken 1000+ garments out of landfills and supported 7000+ workers through Fair Trade USA. The brand also plans to become fully circular by 2030.
Amour Vert offers some beautiful pyjamas made of 100% cupro. They also offer pants and blouses under their Cottonseed Cupro Collection. They package their garments in compostable proactive bags made from recycled materials. They also print using soy-based inks.
For every tee you buy from Amour Vert, they plant a tree in partnership with American Forests.
When choosing sustainable fabrics, it is vital to consider the practices involved at each stage of the fashion industry supply chain. While cupro comes from a natural fiber that is both eco-friendly and biodegradable, it goes through several chemical processes that can harm workers and the environment if not properly regulated.
You can look out for cupro clothing from brands that make it as sustainably as possible.
Sayyed, A.J., Deshmukh, N.A. & Pinjari, D.V. A critical review of manufacturing processes used in regenerated cellulosic fibres: viscose, cellulose acetate, cuprammonium, LiCl/DMAc, ionic liquids, and NMMO based lyocell. Cellulose 26, 2913–2940 (2019). https://doi.org/10.1007/s10570-019-02318-y
Rana, S., Pichandi, S., Parveen, S., Fangueiro, R. (2014). Regenerated Cellulosic Fibers and Their Implications on Sustainability. In: Muthu, S. (eds) Roadmap to Sustainable Textiles and Clothing. Textile Science and Clothing Technology. Springer, Singapore. https://doi.org/10.1007/978-981-287-065-0_8
IHS Markit (Nov 2019) Natural and Man-Made Fibers Overview Chemical economics handbook
Jen’s a passionate environmentalist and sustainability expert. With a science degree from Babcock University Jen loves applying her research skills to craft editorial that connects with our global changemaker and readership audiences centered around topics including zero waste, sustainability, climate change, and biodiversity.
Elsewhere Jen’s interests include the role that future technology and data have in helping us solve some of the planet’s biggest challenges.