Last week, we took a look at superwash yarns and explored why they're not sustainable. TL;DR of that article was that the most common superwash process - the Chlorine-Hercosett process - uses highly toxic chemicals, additional resources compared to non-superwash production processes, and results in a yarn that is not biodegradable and sheds microplastic particles when washed.
Over the course of the last years, quite a few alternative production processes for machine-washable yarns have cropped up, so today we'll take a look at those to see if they are more sustainable!
EXP stands for 'EX-Pollution' and is a process developed by the Schoeller Spinning Group. Instead of chlorine, it uses natural salts as an oxidizing agent, and then adds small polymer patches on the surface of the yarn to make it machine-washable. According to their website, the polymer they're using is 'ecological' - I'm waiting to hear back from them with more information what exactly that means. One gigantic advantage of the EXP process is that it - contrary to the standard superwash process - doesn't release any AOX pollutants into the waste water, making it a lot less toxic!
The EXP process has both the bluesign‚ìá and the GOTS (Global Organic Textile) certificates. This is an indication that it's indeed more sustainable than the Chlorine-Hercosett superwash process as both certificates take a close look at the toxicity, working conditions, wages and environmental impact of production processes.
I wasn't able to find detailed information on a few of the certificates' hazier criteria (What exactly are the thresholds for GOTS','All chemical inputs (e.g. dyes, auxiliaries and process chemicals) must be evaluated and meeting basic requirements on toxicity and biodegradability / eliminability'?), but even so, the fact that the EXP process has gotten them speaks for a higher degree of sustainability.
'A plasma field is generated by discharging a voltage between two electrodes in a special machine. Carefully prepared wool passes through the plasma field where electrons and ions in the plasma interact with the wool fibre. They alter the friction profile of the fibre surface, removing the normal felting effect of untreated wool.
Apparently, the electrons and ions do this by oxidizing the surface of the fibre and creating nano-scale holes. Both help to increase the surface friction of the fibre, which essentially means that the individual fibres stop moving against each other and therefore can't felt anymore, making the yarn machine-washable.
The Naturetexx‚ìá Plasma process has also been bluesign‚ìá certified, and any products that have undergone it can be certified with the GOTS certification - both indications that it is, like EXP, more sustainable than the standard superwash process.
The (really awesome) sustainable clothing company Patagonia has developed, together with one of their suppliers, another innovative process using only ozoneinstead of a chlorine-resin combination to remove the scales of the wool fibres they're using. Oxygen and water seem to be the only by-products of this process (yay!!), which, until now, doesn't seem to be available for other manufacturers.
On my quest to find sustainable superwash alternatives, I also stumbled across mentions of enzyme coatings - organic enzymes being applied to the surface of the wool, reducing the friction between the fibre scales and therefore making the yarn machine-washable. Swans Island offers yarn that's been treated with this process, but I'm still waiting to hear back with more details about the process itself to make an assessment regarding its sustainability.
There are quite a few more processes in development or research that would lead to machine-washable wool with fewer ecologically devastating consequences. None of these, however, seem to be commercially viable and / or available at this point in time. (If I'm wrong on this and you know of one, please do let me know!)
So - what's the conclusion here?
I'm not going to lie, I'm still not a massive fan of any of these alternatives. Additional process steps - beyond the usual spinning and dyeing of yarn - require additional natural resources, and hold the potential for less-than-great working conditions and environmental pollution.
In addition, most yarn companies don't disclose which one of these processes the yarn they're using has been treated with, which makes it hard to make an informed purchasing choice if you prefer one of the more sustainable superwash-like options over the other.
What you can do is to check whether the yarn that's labeled as ‚'machine-washable' also has the bluesign‚ìá and / or GOTS certificate.Those certifications make sure that it hasn't gone through the Chlorine-Hercosett superwash process and is most likely been treated with the EXP or plasma process, making it more sustainable than a traditional superwash yarn.
I do understand, though, that sometimes, a machine-washable yarn is the best way to go - say, if your best friend expects a baby and you'd love to make a cute little sweater for them, but you also don't want to add to the stress level of new parents by making them hand wash it.
For these occasions, I've put together a list of superwash-like sustainable yarns down below. I've indicated whether they've been certified through bluesign‚ìá or GOTS and where they come from so that you can consider both factors for your purchases.
This list is by no means exhaustive, so if you know of any other eco-friendly superwash options, do let me know and I'll add them!
If you want to dive deeper into the different types of superwash processes, this paper offers a comprehensive overview and a range of sources to investigate further. And then there's this slideshow which blew my mind with its overviews of the different finishing treatments - from superwash to non-flammable - for wool!