A Lesson in Sustainable Leather Tanning From the Experts at ECCO
Leather, be it suede, Nappa, or nubuck, has conquered all corners of the market. The versatile grains make up smooth automotive interiors, striking watch straps, and sleek outer jackets alike. If you’re familiar with clothes, cars, or couches, you’re likely to know the difference between patent and vegan, or genuine and faux. However, leather keeps a few secrets to itself: namely, its water-wasting manufacture. With tanneries requiring up to 150 litres of water per day, ‘sustainable’ and ‘leather’ may as well be opposites — but our friends at ECCO are working to change that.
We got the chance to go behind the scenes of DriTan, the company’s new, innovative tanning process. Advancing previous tanning methods, ECCO’s method embraces natural leather properties to ease the stain on resources: each pair of shoes saves one litre of water. For ten thousand years of tanning, that’s a history-making first. Intrigued? We thought so.
A Brief History of Leather Tanning
Before launching into DriTan, we’ll make sure you have decent handle on leather tanning. In leather-making, ‘tanning’ refers to a chemical process that prepares leather for commercial use. To enhance durability and protect against decomposition, chemical agents change the material’s protein structure. The original process, known as vegetable tanning, called for tannin — a class of biomolecules derived from tree barks and plant leaves. Then, in the nineteenth century, chromium burst onto the scene: ‘chrome-tanning’ produces a flexible leather, easily stretched into garments and bags. Soon after, the industry ditched vegetable tanning and transitioned to chromium in droves. Advancements in leather tanneries produced high-quality material, ensuring that leather kept its prestige in fashion. The trend continues through today: in 2019 alone, leather trade revenue was north of US $80 billion.
While chrome-tanning remains the dominant practice across the leather industry, mounting environmental concerns make the process hard to justify. Despite existing for millennia, eco-friendly reforms have yet to break through — tanneries use an estimated 400 billion litres of water each year, leaving loads of toxic sludge in their wake. That doesn’t mean the fight is over, though.
How DriTan Makes Sustainable Leather
Enter DriTan. Using the natural moisture of leather hide, the process minimizes water consumption while continuing to deliver durability with an ultra-smooth texture. ECCO’s Applied Research team found that preserving collagen — a structural protein found in leather — is the key to top-notch results. The final product is indistinguishable from chrome-tanned leather, boasting a full-bodied colour complete with a spectrum of dark and light values.
As you’ll note, ECCO reduces more than just water — the DriTan process cuts the level of chromium in half. Compared with conventional chrome-tanning, the ECCO method lowers CO2e emissions by a sizeable 34%. Other figures are equally impressive: last year, the brand kept a whopping 600 tons of waste out of landfills.
ECCO: The Final Product
Make no mistake: ECCO doesn’t sacrifice style for sustainability — materials have to meet a high standard. Dress shoes warrant ultra-lustrous leather; this class has roots in saddles, bridles, and riding boots. The equestrian world makes an astute parallel to footwear: both leather dress shoes and horseback saddles boast an enduring functionality tempered by a shiny finish. To balance rugged and refined, ECCO sources leather with an ultra-fine grain.
“We require a high quality raw material selection that does not need much upgrading,” the team said. “We create leather that is bare and receptive. [It] can develop a patina and highlights at the right places over time.” Tanners keep the leather grain open, allowing its full character to manifest during later stages of the shoemaking process.
Each type of shoe requires specific leather; soft dress shoes, for example, use a slightly more uniform leather than most. It’s got a soft grain, expressed through subtle textures and nuanced highlights. It’s light to the touch, juxtaposing the stiff, utilitarian finish used in workwear.
To give classic dress shoes their signature polish, ECCO injects a touch of wax into the tanning process. “Wax on leather results in beautiful nuances,” they shared. “The wax in leather is volatile, creating a ‘pull-up’ effect. The pull up effect becomes visible when applying an upward pulling force, causing the dark oils and the waxes to move aside and make lighter colours visible.” The pull-up effect clears the matte look of raw leather, teasing out a range of dark and light hues. The reflective sheen brings highlights to life while strong hides maintain durability.
As a self-described “design-led tannery,” ECCO has cemented itself as a leader in eco-friendly fashion. Thanks to a rich dialogue between artistry and innovation, they’ve revolutionized an ancient practice. Now, they’re well-positioned to face the ever-growing need for sustainability. As raw materials go green, it’s easier than ever for designs to follow suit.