What’s Cupro Fabric, Exactly?

“Is cupro fabric really the eco-friendly, affordable alternative to silk?”

“I was under the impression that cupro fabric comes from cotton, so what’s its connection to silk?”

These are both fair questions, considering the confusing and sometimes contradictory statements about cupro you see floating around online. One person claims cupro is more sustainable than silk and cotton. Another person says that cupro is no better for the environment than polyester.

Getting the truth is more challenging than it should be, which is why we decided to give you the rundown on cupro fabric. Besides answering the basic question—what is cupro fabric?—we’ll give our take on its sustainability and other key characteristics.

What is Cupro Fabric?

Cupro fabric is a semi-synthetic cellulose fiber derived from cotton linter. Cotton linter is the collective term for the short, wispy fibers that hug cotton seeds. They are different from the snow-white flowers that bloom close to harvesting time. Cotton seeds reside deep within the boll, which is the organic container that eventually cracks during flowering. 

Cupro manufacturers take this cotton linter, which would otherwise be discarded, and immerse the fibers in a solution to create a highly viscous liquid. From there, makers weave the material into yarn and sell it as cupro fabric.

By the time it’s finished, cupro’s qualities more closely resemble silk or rayon than cotton. It’s smooth and lightweight. However, like both cotton and (untreated) silk, cupro is biodegradable. Overall, cupro is more environmentally friendly than polyester and other synthetic materials, though added dyes or coatings can obscure that trait of cupro’s.

Is cupro fabric expensive?

Relative to silk, cupro fabric is inexpensive. A yard of it typically costs anywhere from $7 to $30. The cheapest kinds of silk usually start at around $8 per yard, but it’s common for many types of silk to average $50 per yard or more—sometimes up to $100. 

Relative to most kinds of cotton, cupro fabric is a little pricey. Some types of cotton can cost as little as $4 or $5 per yard. A notable exception is organic cotton, which typically starts at $10 per yard. 

How is Cupro Made?

The first step in cupro fabric production is to gather the cellulose fibers from the cotton linter that surrounds the cotton seeds. Because most textile manufacturers throw away cotton linter, regenerating it for other purposes is regarded as a sustainable practice.

Once manufacturers have gathered the cellulose fibers, they immerse them in a liquid containing a mixture of copper and ammonia (cuprammonium solution). The resulting material, cuprammonium, gets immersed in caustic soda (lye). 

After the cuprammonium gets introduced to the caustic soda, the resulting material can start being shaped into small threads. After the threads rid themselves of moisture and excess copper and ammonia, manufacturers begin weaving them together to form the finished product.

Where is cupro produced?

China and Japan are the major producers of cupro, though genuine cupro has been trademarked as the Bemberg brand by the Asahi Kasei Corporation, a Japanese company. Cupro produced in China is usually referred to as ammonia silk. 

Asahi Kasei has a signature closed-loop manufacturing system. Closed-loop manufacturing refers to processes that reuse materials for future production. Bemberg cupro is partially made from reused water, copper, and ammonia.

How does cupro feel?

Finished cupro products have a smooth and silky texture. Most users like it because it is lightweight and relatively breathable. Like silk, cupro fabric drapes elegantly over hard surfaces. On top of being light, breathable, and thin, cupro fabric is anti-bacterial and hypoallergenic.

Is cupro fabric sustainable?

We cannot say that cupro fabric is completely sustainable. Compared to non-organic cotton and polyester, cupro is much better for the environment. Compared to bamboo, hemp, and wool, cupro is slightly worse for the environment.

The main knock against cupro fabric is the cuprammonium solution used in production. Asahi Kesai disposes of the leftover copper and ammonia responsibly, but that’s not the case for every cupro manufacturer. Additionally, many cupro products contain synthetic coatings and dyes. 

Unlike silk, though, cupro is vegan. Silk production requires the death of silkworms through a boiling process.

How to Care for Cupro Fabric

Here are a few general care tips for cupro fabric:

• Don’t fold the fabric product. Cupro is susceptible to creases and wrinkles. We recommend putting it up with a clothes hanger or draping it over a large, smooth surface.
• Avoid excessive heat. Cupro is quite sensitive to heat and catches fire on rare occasions.
• Handle with care. Cupro is relatively stretchy, but it’s still a thin fabric. Show it plenty of love!

How to Wash Cupro

In general, you should avoid washing cupro fabric in hot water. On top of being worse for the environment than washing with cold water, hot water washes can compromise the integrity of the cupro fabric. 

Other rules to live by when washing cupro include:

• Hand wash it when you are able, but most should be fine with gentle cycles in the washer.
• Wash cupro products as sparingly as possible.
• Hang it up to dry or place it on a drying rack away from direct sunlight.
• When in doubt, follow the washing instructions on the tag.

How to Iron Cupro

Follow these tips to iron your cupro product safely:

• Use the lowest/coolest setting possible.
• Use a dry iron rather than a steam iron.
• Iron products inside-out.
• Placing a pressing cloth between the iron and cupro fabric can further protect the product.

Our Take

Overall, we can say we’re fans of cupro fabric. Its derivation from cotton linter, which is usually tossed aside as garbage, is a big plus. Cupro is vegan and feels remarkably similar to silk. We’re big fans of Asahi Kesai’s closed-loop manufacturing process.

Cupro fabric is not without its flaws, but that’s not unlike almost every other textile on the market. Being a responsible consumer is not about being perfect. We feel that if you want a vegan fabric that feels like silk, cupro is probably your best bet.

Featured image via Canva