It’s ubiquitous, superwash wool. Superwash refers to wool that can be machine washed (and possibly dried) without fear of it shrinking and felting to Lilliputian sizes, thanks to one of a couple chemical processes. The first is a chlorinated bath that removes the “scales” from wool fibres, smoothing them out and taking away their ability to lift up and then stick to each other, which is essentially the process of shrinking/felting. All hair has scales, by the way, even human hair–it’s overlapping layers of the cuticle, which is the outermost part of the hair shaft. Wool, especially certainly breeds like Merino, has lots of scales and is especially prone to felting.
Another way to remove the risk of felting is to coat the wool fibres with a polymer, sort of a plastic outer layer that covers the scales. This is all well and good, and superwash has certainly been a boon to the wool industry in general(and has its uses), but it’s not without problems. First, both the chlorination and polymer processes are quite toxic. That last link also gives some info about a less toxic variation of the polymer process, but I’d like to move on to other issues with superwash:
It kind of makes the yarn suck. I know, I know, them’s fightin’ words, but hear me out. Because there are no scales, the fibres become quite slippery, which explains superwash yarn’s tendency to GROWWWWWW when it’s washed. It can be cajoled back to normal size again, but generally not without the use of a clothes dryer, and it adds an extra layer of complication to something that must be blocked (like lace). It also changes the hand feel, especially if there are polymers involved. It’s taking wool and making it, well, more like acrylic. I’m currently knitting a pair of leg warmers from gorgeously dyed gradient wool, but the feel is absolutely terrible in my hands. Superwash strikes again. (Though it should be noted that this varies greatly among mills/producers. Some superwash yarn still feels quite nice.)
While superwash is a handy quality in commercially produced items like my merino base layers for winter sports, I have to ask myself, do I really need machine washability in my handknits? Most of what I knit will be hand washed anyway, especially the lace, and I even hand wash my socks. I don’t need the superwash quality.
So, I end up with my New Year’s Resolution for 2018: I will not be buying any superwash yarn or fiber this year (though I’ll knit with the stuff I already have). Primarily for the environmental benefit, but also because I just don’t like the stuff as much as untreated wool. This may even be a challenge, because superwash is everywhere, and people seem to look for it on the label even if they don’t end up chucking their finished items in the washing machine.
Feel strongly about superwash? Got a nice untreated wool yarn to recommend? Leave me a comment.
What a resolution! It’s always a good plan to source from your stash primarily anyway.
I actually haven’t had that much experience with superwash wool care–I knit I think two sweater projects with superwash wool and, if I had to be honest I haven’t really done much in way of truly washing it because of the horror stories I’ve heard about the stuff growing.
As a novice, seeing all of my hard work become unwearable would just be too hard to bear right now. haha.
Learning what you say about the toxicity of the superwash treatment process makes me think. Is handwashing untreated wool really all that bad? If I’m too much of a noob to hazard a trip for my superwash sweater to the washer/dryer, maybe a nice virgin wool would have done just fine (and better for the environment and feel of the wool mid-knit too).
Your post left me with quite a bit of food for thought.
Glad it got you thinking! For me, I’m not swearing it off entirely in my life (like I said, I live by those washable wool base layers when I’m exercising in the extreme cold!), but there’s so much I just don’t like about superwash that it’s a logical resolution for me. Plus, I already hand wash all my hand knits (with a couple superwash items needing a trip to the dryer to return them to their original, non-giant size, sigh).
I used to have a great superwash sweater from Icebreaker. When it began to feel baggy, I’d wash it in cold water and dry it flat. This would always make it a nice, tight fit again.
I remember when I learned that the fibres were coated in plastic–I was really surprised. But then I probably should have known just by the feel of the material.
I’m less excited about the toxic nature of the superwash process, however.
I have one superwash sweater that I do the same thing with–and I do actually really like the yarn, it’s by Black Trillium Fibres and retains a great handfeel. I wonder if, due to the feel of it and the way it behaves more like “regular” wool, it’s gone through one of the newer, less toxic superwash processes. Unfortunately very hard to find these things out as a consumer!