What's the deal with biodegradable stretch denim?

Olivia Gecseg Monday, 13 April 2020

Last year, news of a remarkable innovation reached the fashion community, one that is sure to make big waves in the field of sustainable denim production in particular. A stretch denim fabric made from plant-based materials that biodegrade, ensuring a low environmental impact and high sustainable credentials, had been created by Milan-based denim mill Candiani for premium jeanmakers Denham’s new collection. Since then, we’ve learned that Stella McCartney’s Autumn/Winter 2020 collection will be the next to feature this exciting new wonder fabric.

But what are the components of this new denim fabric, what makes it environmentally friendly and how widely available is it to designers who want to work with it?


Who’s behind this new fabric innovation?

Dutch Jeanmakers Denham partnered with Candiani, leaders in responsible denim production to make the fabric and bring it to market in the form of the 'Bio Stretch Selvedge' collection. Alberto Candiani is the fourth-generation owner of the Candiani mill, a 75-year old denim manufacturer, based in Milan. The business is known in the industry today for its green credentials in producing sustainable denim as well as for its luxury, “Made in Italy” excellence. It not only supplies leading fashion designers with its fabrics but also partners with big names in the industry, such as Lee, Hugo Boss, and now, Stella McCartney.

Candiani have invested heavily in sustainable innovation, having identified this as a key opportunity for growth. For its 80th anniversary year, in 2018, they debuted Re-Gen, a denim fabric made from regenerated and recycled materials, demonstrating their heritage and appetite for future innovation all in one go. Made using 50% Tencel Refibra and 50% recycled cotton, the Re-Gen denim uses no virgin cotton, arguably the biggest problem when it comes to denim production.

Learn more in this video about Re-Gen and Re-Last, another of Candiani's innovative denims made using Roica, the world's first recycled elastane.

Never mind biodegradable, what is stretch denim?

Denim is a fabric woven using fibres from the cotton plant. Some prefer to wear 100% cotton denim garments for the individual look and breathability cotton offer, but particularly in jeans where people like the fabric to keep its shape to the body, a polyester blended cotton is often used. 

Traditionally, it’s been thought that the polyester blend counteracts the stretch that happens naturally in pure cotton fabric over time and with repeated washing. However, advocates from the raw denim club will tell you that stretchy denim fabrics are actually more destabilised than pure cotton denim, so retaining shape and integrity is all in the wash and care of your jeans. Learn more from denim afficionados Hiut and Blackhorse Lane Ateliers.

With stretch denim, a small amount of elastane (usually between 1-3%) is added to the blend. The amount depends on the desired design outcome. More stretch will produce form-fitting garments that cling to the body, while a lower elastane content will simply add durability and enhance movement to the fabric, without changing the shape of the garment too much.

There's a really great podcast episode from Dressed all about the history of stretch denim, and why we love it so much.

What makes stretch denim bad for the environment?

The synthetic materials used to manufacture stretch garments - i.e. elastane, found under branded names Spandex or Lycra, as well as the polyester or other synthetic materials used to blend the fabrics - are all bad news for the planet.

Made from depleting fossil fuels, the production of these fibres places strain on the planet and emit harmful gases into the atmosphere.

Washing these fabrics is also dangerousa, as tiny pieces of plastic, known as microfibres, are released into water streams, causing damage to ocean wildlife and ecosystems.

Synthetic blended fabrics are also very difficult to recycle, due to the current technologies available in textile recycling plants. This means that garments using these fabrics will usually end their life in a landfill site where harmful methane gases are emitted due to the fact that plastic-based fabrics break down. Otherwise, unsold stock will be burned anyway, releasing toxic fumes. 

What is the Coreva technology and how is it counteracting these effects?

Touted as the world’s first stretch denim that can biodegrade, the Coreva Stretch Technology developed by the Candiani mill allows for the production of a stretch fabric from plant-based yarns. The yarns are made up of a natural rubber core wrapped in organic cotton.

Using all-natural materials, the new fabric has none of the above associated issues. In particular, the fabric’s biodegradable properties are welcome due to the current concerns of vast streams of waste coming from the fashion industry. 

Although we know that the use of toxic chemicals in denim production can negate the implementation of organic cotton (over conventionally grown cotton), the makers behind the fabric also claim to have found solutions to these issues. 

So called "smart dyeing" methods are reducing water consumption and chemical usage, with the opportunity to lower energy consumption in production all contributing to the fabric’s eco-credentials. 

It's actually incredibly fascinating and makes you look at "everyday" materials in a new light. Kitotex Vegetal, a biodegradable ingredient made from seaweed and mushroom, replaces polyvinyl alcohol (that's PVA) used in the starching, fixation and sizing agents that go into denim manufacturing. This is a vegan version of a previous water-saving technology Candiani used, ensuring an animal cruelty-free aspect for the denim too.  

Who’s used it so far?

The first range of 'Bio-Stretch Selvedge' jeans was launched exclusively in 2019 in partnership with premium Dutch jeans manufacturer Denham, founded by English jeanmaker Jason Denham in 2008. According to their website, Denham “approaches design with a passion for innovation while honouring tradition”. No surprise then, that they partnered with Candiani to launch this cutting-edge collection.

Stella McCartney appears to be the latest brand to use the Coreva technology. For their Autumn/Winter 2020 collection, ten pieces in two styles will be made from the new fabric. The collection was announced to be available in stores from May 2020.

Will it take off?

While there’s a growing following for 100% cotton jeans, along with "raw denim" if created without any wash treatments, it’s still a niche market, and so a sustainable solution to stretch denim has the potential to be very impactful on the denim industry if it can be widely used. 

In the recently released 2020 Conscious Fashion Report from Lyst searches for sustainable denim among consumers were noted to be among the key trends, with “organic cotton”, “recycled plastics” and “biodegradable” terms all linked to denim-based search hits.

No surprise here really, as denim garments - namely jeans - remain among the globally most-wanted fashion items year-on-year. Furthermore, jeans are often the most worn garments in people’s wardrobes. Shoppers are keen to seek out long-lasting options for their much-loved denim pieces while following trends towards increased sustainability. 

It looks to be still early days for the fabric and while both Candiani’s mill and Stella McCartney warehouses are currently unable to operate under restrictions during the Coronavirus pandemic, it’s unknown whether this will go ahead on schedule.

The Jeans Redesign Project

Coming from the Ellen Macarthur Foundation, the Jeans Redesign Project sees brands and stakeholders including fabric mills and textile recyclers come together to envision a circular future for this complex clothing item. The guidelines as part of the Make Fashion Circular initiative sets a requirement at protecting those in the supply chain, along with setting minimum requirements for jeans on durability, material health, recyclability, and traceability.


Read more thoughts about the topic from these publications:

Sportswear International

Eco-Age

WWD