Surface Design with Natural Dyes

 Blog

Rachel: “I found these cute block-printed throw pillows I want to make. How can I do that with natural dyes?”

I’m mostly a spinner and knitter, but in the natural dye classes that I attend at OCAC, there are a lot of people who focus on textiles. We’ve used a simple technique to get a lot of different results, and it’s really a lot of fun.

You will need the items you wish to print with: print blocks, stencils, potato stamps, paintbrushes, silkscreens, or anything else, and a few pieces of equipment: a blender, a steamer, an old bedsheet, and gum tragacanth. Gum tragacanth is a natural product that is most often used making fondant for cakes. Here it’s used as a “sticking” medium. What’s good about gum trag vs. other similar products is that it doesn’t interfere with or change the color of your dyestuff.

The technique: mix up some gum trag and water in a blender. Say, 1/4 C gum trag and twice a much water. You will hear and feel the mixture get thicker after about thirty seconds. If it’s too thick, add more water. If it still seems a little runny, let it sit for a bit, it thickens over time. Don’t mix more than you’ll need for your project at hand, because it only lasts about a day in the refrigerator. (Obviously it will be easier to judge once you’ve done it, but a little medium goes a long way.) You will want it thick enough to adhere to your stamps, but not so thick that you lose definition. If you’re silkscreening, you’ll want the thickness of silkscreen ink. Make some practice stamps before you commit to your fabric!

Mordant Printing

You can mix a mordant into your gum trag mixture. We used very small amounts of copper and iron, and a slightly less small amount of alum during our classes.

Gum trag with mordants

Here is a thread spool print with copper mordant:

Here I’ve printed on a silk scarf previously dipped in indigo with alum, using a feather for my print:

Here I’ve used an iron mordant on silk noil, again with feathers. I used an old paintbrush to apply the mordant mixture:

Discharge Printing

You can mix and acid or a base into your medium to discharge color on an already dyed piece.

Gum trag with soda ash

Here I tried using soda ash to shift the color on a pisolithus mushroom-dyed piece of silk:

Here I’ve used tartaric acid to discharge the logwood dye on silk organza:

You can do combinations of these techniques:

Discharging with a print block

And printing with an iron mordant

How to set your prints:

Lay out your dried fabric on an old cloth in a single layer, fold extra cloth over, and roll up, jelly roll style so that it will fit in your steamer basket. You want STEAM ONLY! Take care that the water is not getting into the bottom of the basket, and place a towel or piece of felt on top underneath the lid to keep condensed water from dripping back down. Make sure you’ve got steam going before placing your jelly roll in the steamer basket. Steam ten minutes, and remove carefully. Let cool until it’s comfortable to handle, then unroll.

Jelly roll in steamer basket

Wash your steamed fabric in warm, soapy water to get the gum trag residue out. It still contains mordant, discharge or dye, and if the excess isn’t washed out it will go into your dye pot and change the result.

Here are some results after dyeing our prints. The yellow is from onion skins, the pink from Brazilwood, and the orange a combo of both.

Here are my feathers. You can see that the gum trag wasn’t washed out completely by the extra dark muddiness around the onion skin feathers.

I decided to after-mordant the whole piece in alum, and not only did that get rid of the excess print fuzz, it changed the color of everything. It’s a bit 1970’s decor now, but I think it will still make a nice pillow:

For the discharge printing, you don’t necessarily have to steam the piece before washing. Here’s a sample of logwood on silk that I discharged by painting the back of a leaf with gum trag and citric acid, and then simply washing when I liked the result. It made a nice multi-colored effect:

I steamed my Ph-shifted fabric, and once I washed it out it ended up being merely discharged. I think I would have had better results if I’d washed it out as with the leaf print:

And here is a piece of silk crepe de chine that I silkscreened with alum and then dyed in Osage orange:

So, to answer your question Rachel, you have a lot of options. You can make a mordant print on unmordanted fabric. You can make a (different) mordant print on mordanted fabric. I didn’t include any photos, but you can mix natural dye extracts with your gum trag and print directly that way, with color. You can discharge already-dyed fabric. And you can do combinations of these techniques. You’ll no doubt have noticed that all these examples are on silk, but many of my classmates used this same technique on cellulose fibers.

There is also the option of surface design using natural pigments, which I’ll cover in my next post.

Fun with Cochineal

 Sally Williams

 Blog

After indigo, I bought a cochineal dyeing kit which contained the bugs, several mordants and some vague instructions. (I say the instructions were vague, but really they gave several options as far as time vs. temperature in mordanting. It’s one of those things that once you know what’s going on makes perfect sense.)

Rachel and I did a test run when she was here last April (Sheep Cabana retreat: dye as much stuff as possible in 48 hours), and here is what we came up with:

Cooking and straining some cochineal bugs

We started with 4oz of dried cochineal (which is a lot), cooked them for about an hour and then strained the liquid into the dye pot. I saved the used bugs for later. Then we mordanted our wool. We used some white Shetland and some grey mohair locks, and mordanted with both alum and tin, by simmering our fiber in each mordant bath for about an hour. I would say that our mordanting pots weren’t large enough, because the tin-mordanted wool definitely felted.

The dye pot, onion bag of mohair locks on top

We could have used a bigger pot.

Viola!

Here are the results, from top clockwise: tin mordanted wool, alum mordanted wool, alum mordanted mohair, iron after-mordanted wool, iron after-mordanted mohair.

Rachel left, and after a couple of months I got out the leftover cochineal bugs again and tried some more dyeing. (Those bugs sat on my patio in that plastic container, above, the whole time, ignored. I had no issues with them rotting or anything else unpleasant.) I re-simmered the bugs and left them sit overnight in the pot, and strained the bugs out in the morning. Then I did a series of successive dyeing on 50g each of alum and copper-mordanted wool:

Top, alum mordant
Bottom, copper mordant

I heated the cochineal dye pot, added the mordanted wool and let it sit out on the patio here either all day or overnight. The total hands-on time was probably 1/2 hour.

Here it is spun up:

Successive alum mordant, left to right, with copper mordant wound into a cake far right. The orange is the immediately adjacent cochineal overdyed with weld.

I’ve been taking some natural dyeing classes at the Oregon College of Art and Craft, and one of the neat things we did was dye with cochineal with no metal mordants. Instead we used 25% WOF of cochineal, 10% WOF powdered gallnuts (Gallic acid) and 10%WOF citric acid, all in the dye pot at once. Hot tip: we ground up the cochineal bugs and a little water with a mortar and pestle. No soaking required.

We simmered wool and silk noil for an hour and got these lovely colors. The cochineal strikes the wool and silk differently!

Shibori cochineal on wool

Left, wool, right, silk noil

These are nice colors on their own, but I also wanted to experiment with this dyeing method as a base color. Here is the same fabric overdyed with indigo. One of the very interesting things about cochineal is that the color will shift from red to blue, depending on Ph. The middle samples are overdyed with indigo (about Ph 12) and rinsed, the far right are the same, but rinsed in a white vinegar solution (about Ph 3).

Cochineal overdyed with indigo

I also tried some after-mordanting, with iron, copper and alum mordants:

Left, iron after-mordant
Middle, copper after-mordant
Right, alum after-mordant

There is really a lot you can do with these little bugs, and a huge range of color, depending on what techniques you use. In other words, fun!

Natural dyeing with cotton

 Rachel Wolcott

 Blog

left to right: onion skins, madder, indigo on organic cotton yarn

It’s funny what can get you off and running on a project. Dyeing cotton really wasn’t on my to-do list until I read an article in the Winter 2015 Spin Off where Dye-lishus premordanted cotton sliver was tested and reviewed. My first thought was, what’s the fuss with cotton that would make premordanted sliver desirable? Would it make dyeing easier?

One of the things the Dye-lishus premordanted cotton sliver apparently can do, which home mordanting can’t, is allow the fiber to take acid dyes, which are made for dyeing protein fiber (wool, silk, etc). Dye-lishus’s USP is: you can dye this fiber with anything–acid dye, food colouring, procion dyes–and it will stick.

However, my interest in mordanting my own cotton was stronger than my desire to try out the Dye-lishus fiber. Another day perhaps.

A quick internet search informed me that mordanting cotton for natural dyeing is a two- to three-step process, depending on the kind of cotton used. It’s not complicated. It’s not particularly labor intensive. It’s just one or two more steps than mordanting wool.

There are some important things you should know before mordanting and naturally dyeing cotton.

* Cotton is mordanted with tannic acid, then aluminium acetate. Those are different mordants than the ones used for wool. Both are available from natural dye suppliers.

* Depending on what kind of cotton you’re going to dye, you may want to scour the yarn or sliver. I washed my yarn in very hot water with soda crystals. If you’re using organic cotton, don’t bother with this step.

As with all aspects of natural dyeing–on cotton, wool or otherwise–there are many recipes. I used the simplest one I could find, which happened to be on the Wild Colours site. It has lots of information on natural dyes and mordants.

I used 10 percent of weight of goods (WOG). To mordant 100 grams of fiber and yarn, I used 10 grams of tannic acid and 10 grams of aluminium acetate. It’s worth getting a digital scale to weigh the mordants. Put a clean yogurt pot on the scale, zero it, then tip in your mordant.

Soak your fiber/yarn for a good hour before adding it to a dye pot in which you have dissolved 10 grams of tannic acid. You want there to be enough hot water to cover the fiber and give it a bit of room. No need to heat the pot, just leave it until you’re ready for the next step. I left mine overnight.

Repeat the process, but this time dissolve 10 grams of aluminium acetate and then add your wetted down fiber. Again, you need hot water to dissolve the aluminium acetate, but you don’t need to heat the pot. I left mine to soak overnight in a bucket.

When ready to dye the fiber, make sure to rinse it well to get out any mordant that hasn’t attached to the fiber. Do it now or it makes the fiber a bit chalky after dyeing. Otherwise make sure to rinse your fiber well after dyeing.

I dyed with madder and onion skins, because that’s what I had to hand. I soaked the madder root in hot water overnight. I used 50 percent WOG of madder. Onion skins are very generous in terms of dye yield. I used a few handfuls and that was plenty.

cotton yarn, madder dye bath

Give the madder about an hour to simmer. I strained the root into a jelly bag, which I then returned to the dye pot. It saves you having to pick out little bits of madder from the fiber and makes sure you’re getting your money’s worth from the dyestuff. I fished out the onionskins with a slotted spoon put them in the compost.

Once the fiber was in the dye pots I left them to simmer for about an hour. I then removed them from the heat and left them to cool.

Dye baths made with natural dye stuffs do not exhaust the way acid dye baths do. That means there will appear to be a lot of color left in the dye pot. With acid dyes, you know the dye bath is exhausted when the water is clear. That doesn’t happen with most natural dye stuffs.

madder on cotton sliver

top: cotton sliver, bottom: cotton yarn with onion skins

Rinse your fiber well and leave to dry.

Last, but not remotely least, cotton can be dyed naturally without any mordanting or pretreatment whatsoever. Just make an indigo vat, following Sal’s fabulous fruit vat instructions. Indigo is a substantive dye–like walnuts and lichen–and does not require any mordanting process. Just look at it. Beautiful!

Indigo on cotton yarn (top), wool (middle), sea cell (bottom)