amigurumi

amigurumi

Friday, March 18, 2011

Shibori-Dyed Yarn part 1: Natural Dyeing

It's taken me a while to get around to posting about the yarn pictured near the top of my blog, but thanks to an inquiry from a natural dyer from ravelry I decided it was time. One of the things that drew me to fibre arts in the first place was the idea of making something from bits of things, particularly if they're bits of things you find laying around... Considering all of the yarn, needles, hooks, tools, wheels, looms, I-could-go-on-forever that I have in order to satisfy this desire, I think the closest I actually get to fulfilling it is with natural dyeing. Although I have bought large enamel pots for dyeing, I also use cast-off aluminum pots (given to me by friends who have read about the dangers of cooking in aluminum...) plus old bowls, colanders, sheets, wooden spoons, chopsticks, etc have also been called into service. Many of the dyestuffs I can grow or harvest myself (or attempt to), and I get my mordants from the local bulk-food supplier for cheap.

Considering the time & energy it actually takes to use plants (& bugs, etc) to dye yarn, you may wonder why bother? I could say, why bother to weave, or knit, crochet, or spin? The answer would be pretty much the same to all questions- because I like doing it. So I do. In my particular case, the interest may have something to do with the nearly 10 years I spent working as a microbiology lab tech. I love learning & understanding how things work, so the chemistry behind natural dyeing isn't voodoo to me (& I have taken dye workshops with folks to whom it was voodoo... !). Maybe this understanding makes me successful often enough that I keep on doing it. Mostly, I just looooove the colours you can get with dyes found in nature. The colour you get from onion skins makes me wish for a revival of the popularity of colours with names like ochre, burnt orange, & rust. Sigh.
From left to right (top): brazilwood (2 skeins), brazilwood exhaust (4 skeins) , yarrow (2 skeins), onion skins, (1 skein) yarrow exhaust (2 skeins).

The other fun thing about natural dyeing for me is that it's unpredictable (often in interesting rather than disappointing ways...) and that it borders on the magical. Ever exploit the pH qualities of certain dyes to get different colours? When I used to teach natural dyeing workshops I would use just 2 dyes, but everyone would go home with at least 8 skeins of yarn dyed  in 4 or more colours because we'd dip the pH-reactive brazilwood-dyed skeins in vinegar (for shades of rust & brown) or ammonia (for shades of fuscia & bright pink). Plus, using exhaust baths (already-used dyebaths that still have colour in them) will give you lighter shades. And there is really nothing to compare to the chemical magic of indigo, coming out of the vat green & turning blue when the air hits it. I still get a thrill, after ~10 years of doing indigo.
Silk & wool blend yarn, leaf-patterned knitted mitts, yarn-dyed in indigo.

Since natural dyeing is basically using chemicals from nature, one of my first concerns when I got started was safety. My lab training helped, of course, but so did the second-hand Merck Index that I found on a used book site. (ok, I was just looking for an excuse to own my own copy, after years of thinking longingly of the one I left behind in the lab... great lunchtime reading) The main area of toxicity when it comes to natural dyeing is the mordants, which are the chemicals that allow the dyes to become colourfast. Different mordants also affect the resulting colour you get with natural dyes, but many mordants are heavy metals like copper & iron, & you have to be exceptionally careful not to inhale them or contaminate anything else with them because they are very toxic. I simply prefer to expand my colour possibilities using means other than heavy-metal mordants. I do read occasionally of folks who say forget mordanting & just enjoys the colours while you have them, but that just isn't practical to me. If I'm going to go to the trouble to do it, I want it to stick! This attitude limits the plants (etc) that I'll use for dyeing, for example, the colours from berries & beets don't mordant well, in my experience, so I don't use them. Sometimes experimenting with these limits have led to success, which is really fun. For example, I'd read that turmeric is not lightfast with alum mordant, which is the safest mordant & pretty much the only one I use. So I decided to try mordanting it with black tea, which is a mordant because of the tannins. I have a nearly -10-year-old multicouloured shawl (see below) that can attest to the lightfastness of turmeric mordanted with black tea (& I have the notes I used to do it, so I can do it again if I want!).
The gold stripes at top & bottom are turmeric.

Which does lead me to one of the often-cited downfalls of natural dyeing- reproducible results. Factors such as where the dyestuffs are grown, growing conditions from year to year, what parts of the plant are used, and how the dyestuff is prepared will lead to differing amounts of the chemical that does the dyeing to be present. This does not lead to reproducible results. As I mentioned above, I like the element of surprise that comes along with natural dyeing, but I also keep careful notes, & my notes over the more than 10 years I've been doing this have allowed me to streamline some aspects of the dyeing process. For example, usually I mordant all the fibres I'm going to dye at the same time. I weigh all the fibres, calculate the amount of mordant needed, & then use one of the big aluminum turkey roasters over 2 burners to mordant the world... I mean wool. However, I've also found myself in situations where I need to dye some yarn & I don't have anything mordanted, & time is of the essence. I've learned that, if you do it right, you can mordant at the same time as you dye, or even after (as in the case of dyeing over indigo, which doesn't require mordant) & it works. I also write down what didn't work so I don't forget & do it again :)

If there is a limitation to natural dyeing that I find a bit frustrating, it's the fibres that you can dye with natural dyes. Basically, it's really hard to mordant plant fibres, such as cotton & linen, so they're colourfast, which leaves pretty much indigo. I've heard that anatto works on plant fibres & I have some, but I haven't tried it yet. (stay tuned...) I also find that silk is a lot pickier about lightfastness, & I have yet to get indigo to stick properly to silk, although I try it all the time :( I can get it to stick to silk & wool blend fibres just fine, but pure silk is another story. So I'm still investigating & learning, as you can see.
Cotton throw dyed in indigo.

So, when it comes to dyeing with anything but indigo, I dye wool & silk in various forms & combinations. I have dyed raw fibres for spinning, but prefer to dye already spun yarn (just a preference, really). If I'm experimenting I always dye a mordanted silk chiffon scarf along with the yarn, so I'll know how the colour takes on silk (& to add to my very colourful collection of silk chiffon scarves :). All skeins are figure-8 tied loosely-very important!- usually with cotton string or yarn for the ties because they won't felt or shrink- otherwise you end-up tie-dyeing your yarn. The ties keeps the yarn from tangling impossibly during the dye process. Speaking of felting, a lot of people worry about putting wool through so many pots of boiling water in order to dye it, & although it does felt a little (gives it a fuzzy finish), if you remember to always go from cold to warm you will minimise felting. In other words, you can do about anything you like except plunge hot, wet wool into cold water. Don't do that if you want to use the fibre afterward... I also label the skeins I'm dyeing, using washable interfacing & sharpies, with cotton strings, because it's amazing how different yarn can look after you've dyed it. When the skeins are dry I replace the dyed tags with paper ones, recording the dye used along with the weight, fibre content, & yardage.

The main dyes that I used for dyeing are: brazilwood for reds & oranges (& occasionally cochineal, which is really bugs, but for all that is very safe, but expensive!); indigo for blues; tansy, yarrow, & golden marguerite for yellows, onion skins for rust/oranges; safflower for brighter (practically fluorescent...) oranges & yellows; and black walnut or alkanet for browns. I have gotten some very nice tans from birch (inside bark or leaves) & Rose of Sharon (from purple flowers-watch out for bees!), & a softer tan from rhubarb leaves (also works as a mordant). I get purples & greens by overdyeing reds & yellows with indigo. I have tried many other plants- goldenrod, woad, weld, tomato plants (!), logwood, and others I've forgotten right now, but with unspectacular results. You could say that the above listed dyestuffs are my stand-bys, & many of them are sitting in the basement right now, waiting for a hot pot, some water, & wool :) As mentioned above, I mordant using alum & cream of tartar, which are both used in food & perfectly safe. All of the dyestuffs above are also safe in the kitchen, but none should be ingested, & yarrow & tansy work best outdoors because of the smell.

This brings me to an important safety point: always segregate your equipment! In other words, what you dye in is never used for food (& vice-versa). I do most of my dyeing on the stove in the kitchen, but I'm very careful not to use anything- pots, measuring devices, spoons, even scales for measuring- that I'm going to use for food. If I accidentally grab something & use it, it automatically becomes part of my dyeing equipment. I no longer cover the kitchen counters with newspaper, as I used to, but I'm very careful about spillage. Most of the clean-up takes place in the basement stationary tub, too. I have an old, big crock-pot that I use for small batches of tansy or yarrow on the back deck. If I'm dyeing in the basement, I always cover everything with dropcloths because my dye area is also the laundry area, & never the twain shall meet, when it comes to dyes... it's surprising how well something will stick to unmordanted cloth if you don't want it to. I also wear gloves, old clothes, old shoes, & aprons when I dye. Pretty much the whole world knows what I'm up to, in other words.

My main resources for natural dyeing, book-wise, are Jenny Dean's Wild Color (the old one) and Rita Buchanan's A Dyer's Garden. I may have some other books laying around, but these are the ones I actually use, along with my dye notebook. I have enjoyed exploring Jenny Dean's book for some years. although I may not get all of the colours she says she's getting, from all the plants she suggests (plus I'm not using all the mordants she lists because of the toxicity thing). But I use her recommendations for mordanting & concentrations of dyestuff & it's been a good solid resource. I have also tried Rita's direct-dyeing method for indigo, but, in trying to use woad from my garden, my success was hampered by lack of the amount of dyestuff you really need to make it work. My neighbour grew Japanese Indigo last year & had some success with it, though.

My other dye resources, in terms of dyestuffs, depend on the dye. I usually get exotic stuff, like brazilwood, from Carol Leigh or Dharma. (Dharma also has a nice line of yarns for dyeing) Brazilwood usually comes as sawdust or wood shavings (it's the heartwood of a tree from, you guessed it, Brazil) & is a by-product of the violin bow-making industry. I usually double-strain brazilwood sawdust before putting the fibre in the pot because the bits stick to the fibre & won't come out easily.  Herbaceous dyestuffs, like tansy, yarrow, turmeric, or alkanet I get from Mountain Rose Herbs, when I don't grow them myself. I have gotten indigo from both Carol Leigh & Dharma, but Paradise Fibres carried instant indigo, which is freeze-dried indigo crystals right from the vat (John Marshall talks about it at this page) and ready to go, which really simplifies the process, especially if you're doing it with groups. The biggest pain of dyeing with indigo without using instant crystals is that it's hard to find powdered indigo, & powdering the rock-like lumps of indigo usually sold is one of the messiest jobs I've ever done. So, look for powdered indigo! (or use crystals :) I have very little experience with the dye extracts some people make & sell. I think they're really expensive & most of the time I would rather go through a little extra trouble rather than pay exorbitant prices.
Some yarn & silk scarves after natural dyeing.

Another word about indigo- as I sort-of mentioned above, indigo doesn't need mordant to stick. That's because it doesn't interact with the molecules of the fibres the same way that natural dyes do (in the presence of mordant, I might add...). It's deposited on the surface of the fibres, which is why your denim jeans get wear marks on them. You can dye most anything that can be dyed, in indigo, which is really fun. However, it's not all fun & games. Indigo is sensitive to temperature, pH, & amount of oxygen that is introduced to the vat by the process of dipping things in it. When this balance is lost, the indigo stops being deposited & the vat no longer works. Some ways that I overcome these while dyeing with indigo is to have a heating pad under my vat (under plastic to protect it from getting wet) & adding insulation around the vat as well (styrofoam packing "Peanuts" work well, also under plastic). A friend used an aquarium heater to keep her vat warm over time. As with any dyeing, you have to we the fibres before dyeing, so I wet them in hot water when using indigo, to help maintain the temperature of the vat. Since I'm wearing rubber gloves I don't really notice the heat. Pre-wetting the fibres is one important way to avoid bringing too much oxygen into the vat, & I'm also very careful about squeezing the dipped fibres below the surface of the vat before lifting them out, to avoid splashing the vat, & then wring them out over a nearby bucket. Over time, when re-dipping cooled fibres for deeper colours, it's inevitable that the vat will cool down, but I have re-used vats by re-heating them & sprinkling some RIT dye remover in to remove excess oxygen. After 15 minutes it should be ready to go again. It's really hard to fully exhaust an indigo vat, so it may be worth trying to revive it.

I'm not going to be specific as to how to dye with natural dyes in this post, since the resources I've mentioned are a very good starting place. In part 2 I'll explain how I used natural dyes to shibori-dye yarn. 

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