tartaric acid – Ink, Yarn & Beer

Cochineal, i

Cochineal is a dye native to the Americas, in use by indigenous peoples long before the Spanish came. Once discovered, it became a source of wealth for the conquistadors, and a well-kept secret. It replaced or supplemented many other natural red dyes, such as madder root, used throughout Europe and Asia. As with quercitron, Edward Bancroft wrote extensively about cochineal in his books about dyeing.

Cochineal is derived from bugs that grow on cactus plants. They are collected, dried, and then ground prior to use as a dye. Trudy van Stralen, in Indigo, Madder & Marigold, recommends grinding them up as fine as flour, using an old coffee grinder dedicated to that purpose. I have a molcajete, which I used. The result was very finely powdered bugs. An interesting odor arises when grinding them – rather sour – which is not something I expected. Also, the rather pale bugs release a deep red color. The molcajete was easily cleaned by running water into it while grinding with the pestle. It was then set aside to dry.

Indian Collecting Cochineal from a Cactus with a Deer Tail

Using van Stralen’s percentages, I used 10% of the fiber weight (here, 100 g) for the bugs, and 5% of that for the tartaric acid in the dye bath. Thus, 10 g of ground bugs were used with 5 g of tartaric acid. These were mixed together, and set aside to soak overnight in warm water.

As with the quercitron, I filtered the cochineal solution prior to placing it in the dye pot. Because the cochineal is so finely ground, coffee filters are very slow. Van Stralen suggests old sheeting, which I don’t have, so what I do is piggy back the liquid into a number of filters. When the filtering process becomes very slow, I lift up the currently draining filter, slide a new one into the cone, and decant the liquid from the old filter into the new. I also continue to pour the overnight stock into each newer filter. This time I used about 5 filters, but the process was not particularly tedious. The used filters, bugs and all, are then set aside to be used for later dye sessions.

The final result is a very clear liquid, with little particulate matter.

Quercitron, ii

Today’s adventure is simply about dyeing with the quercitron and the colors I got.

Dr. Edward Bancroft is credited with utilization of the Eastern Black Oak for yellow dyes. In his book, Experimental Researches Concerning the Philosophy of Permanent Colours; and the Best Means of Producing Them, by Dyeing, Calico Printing, &c, he devotes an entire chapter to Of the Properties and Uses of Quercitron Bark. If you wish to read about the history of quercitron, the above links are worth pursuing.

You can also read what I’ve written about it as well.

And if you have read a bit of what I have written about using quercitron for the flammegarn, you will recall that I set it up the night before. For today’s dye bath, I used 15 g of the powdered bark, soaked in warm water. This morning, I strained it out, and set aside the coffee filter to reuse later. I soaked the yarn to be dyed while the dye pot was heating up. The yarn was premordanted with alum and tartaric acid a week or so ago.

Filtering out the dye matter is important. The quercitron is finely ground, and if left loose in the dye pot with the yarn, it would easily get entangled in the yarn or fleece, and require a lot of time to remove it. Trust me, it’s not worth skipping this step! Coffee filters are ideal, and then the sludge may be set aside to dry out for reuse. I do this with some other dyes, such as cochineal and brazil wood, even though subsequent uses will be weaker.

I used my largest dye pot, even though I was dyeing a small amount of yarn. The reason for this is that the temperature of the dye bath is more easily controlled. This is critical to keep the dye toward the yellow, rather than brownish, side.

When I made the flammegarn last weekend, I kept the yarn in the dye pot only about 20 minutes. Today, the yarn continued in the pot on the heat for an hour, and then was given time to rest in the cooling liquor. After that, it was dipped in a vinegar bath, which, as Bancroft notes, causes the dye to move toward yellow rather than toward a brownish or greenish color. While I have not tried it, Bancroft states that “tin, mixed with a decoction of the bark, produces and exceedingly beautiful lively yellow.” Perhaps an afterbath of tin would be worth trying.

In the pot is lace weight alpaca, and handspun white fleece. The final results are below.

As you can see, the alpaca took up the color more deeply – perhaps it is the nature of the fiber.

Quercitron, i

The Eastern Black Oak (quercus velutina) is a common, medium-sized to large oak of the eastern and midwestern United States, with a range that runs essentially east of the Mississippi. Other names for this tree are yellow oak, quercitron, yellow bark oak, or smooth bark oak. It grows best on moist, rich, well-drained soils, but can also grow in less optimal conditions. Its acorns take two years to mature, unlike those of other oaks, and are rather squat and round. It belongs to the family of red oaks.

Black oaks are medium to large trees, growing to a height of 80-100 feet, with trunks about 3 feet in diameter. The leaves have 7-9 lobes, and vary in length, from 4 to 10 inches. During the summer, the leaves are a crisp green color with paler shading underneath. In autumn, the leaves turn to red. The bark of young black oaks is smooth with light grey coloring, but with age, deep furrows develop and the bark becomes thicker and darker. The inner bark is an orangish-yellow color, and it is from this that the dye quercitron is derived.

According to Wikipedia,

Quercitron is a yellow dye obtained from the bark of the Eastern Black Oak (Quercus velutina), a fine forest tree indigenous in North America. The name is a shortened form of quercicitron, from Latin quercus, oak, and citron, lemon, and was invented by Dr. Edward Bancroft (1744-1821), who by act of parliament in 1785 was granted special privileges in regard to the importation and use of the substance. The dyestuff is prepared by grinding the bark in mills after it has been freed from its black epidermal layer, and sifting the product to separate the fibrous matter, the fine yellow powder which remains forming the quercitron of commerce. The ruddy-orange decoction of quercitron contains quercitannic acid, whence its use in tanning, and an active dyeing principle, quercitrin, C₂₁H₂₀O₁₂.

Edward Bancroft was an interesting character, born in the mid-eighteenth century in pre-revolutionary America. During his lifetime he was – according to varying sources – apprenticed to a physician, a scientist, a writer, as well as a spy and double agent during the American Revolutionary War. He was a secretary to American Commission in Paris, working for Benjamin Franklin, as well as spying on the British, and for the British. (Whew! That must have been complicated!) After his life as a spy, his scientific side is credited with having discovered that the inner bark of the Eastern Black Oak, a tree found throughout the midwest and east coast, produced a colorfast and lightfast yellow dye which matched, and possibly surpassed, the common European yellow dyes of the time, such as weld and fustic. Bancroft received English and French patents giving him the right to import the bark, and this made him a rich man in the latter years of his life. Before his death in 1821, Bancroft had published a number of books on natural science, and on dyeing; it is on this latter subject he wrote two volumes, published in 1814: Experimental Researches Concerning the Philosophy of Permanent Colours.

The inner bark of quercus velutina is finely ground before being used as a dye. It is my hope that the harvesting of this bark is done sustainably, without damaging or killing the tree, unless it is harvested for its wood.

Flammegarn

Early this morning, I got up to meet a cool, breezy morning with a clear sky and the promise of perfect weather. What more could be asked for on a day when the morning is to be spent outdoors dyeing yarn? Everything from the last pre-dyeing days was gathered together – the pans, the spoons, scales, and so on, including the skeins of pre-mordanted yarn. Today, a number of things were planned, and happened: dyeing both commercial and handspun yarn with cochineal and black oak bark, also known as quercitron.

What is flammegarn?

Today’s entry is about flammegarn, which is an old Scandinavian method of making yarn with variegated colors. A skein (or two, or three) is tied off with cord, immersed into a dyepot, and colored. The result is a “flame yarn” – so named because this was traditionally done in red over white yarn – with splotches of red and white coloring which knit up into a space-dyed yarn. Modern dyers do this – just google “flammegarn” and you will find a number of examples. Earlier this year I wrote about making flammegarn with commercial dyes, which you can read about here. Judy’s knitted up some socks out of her flammegarn – I need to get a picture of them to post.

Set up the dye materials the night before.

Last night I prepared the dye materials. Specifically, I ground up 5 g of cochineal bugs, and mixed them with an equal part of tartaric acid. Then I added hot tap water, stirred them together, and let them sit overnight. I weighed out 10 g of black oak bark, and did the same, but without the tartaric acid. I did about five dye baths this morning; out of these, two were used for the flammegarn, which is fingering weight, commercially spun blue-faced leicester in two 200-yard hanks.

Filter out the particulate matter.

The dye pot was set up by filtering out the particulate matter from the water into which I put it last night. I used an old coffee filter and a paper filter; the filter was set aside and the clear liquid placed into a large dye kettle.

Cooler dye bath temperatures are better for yellows.

Even though I was using only about 135 g. of wool (100 BFL, 35 moorit shetland), I wanted a large kettle. A larger kettle is easier to control as far as not allowing the temperature to rise very high. This is especially important with yellow as the hotter the temperature, the more the yellow can drift toward brown or greenish hues. I kept my pot around 140-150 F. The weight of dye matter to fiber (the BFL specifically) was 1:10 – 10 g. oak bark to 100 g. of BFL, which had been premordanted with alum and tartaric acid.

According to J.N. Liles, most of the black oak bark color will be taken up in the first 20 minutes of immersion. This proved to be the case. I pulled both the BFL and moorit out periodically to check the color, and once I liked it, I put in a piece of copper pipe – about a thumb’s length – and a pinch of gypsum (the chalk my husband used in beer making to change the pH of his brew, as well as increase the availability of calcium and sulfur ions). Liles recommends adding “1/2 tsp. of chalk” but doesn’t state whether it is calcium carbonate or sulfate, so I used the gypsum. The color in the pot became a tad bit brighter – a rather mellow, pale gold.

Prepare the flammegarn by tying off sections of the skeins.

While the dye bath was heating up, I took my two BFL skeins and tied string around them. The string acts as a resist, keeping the white (or lighter colored yarn) from getting dyed. After this, they were set into hot water prior to immersion into the dye bath.

This yarn was removed from the pot and set in a basin to cool enough so it could be handled for untying and re-tying to create the flammegarn yarn. While the fibers cooled, I took the remaining particulate matter of both the quercitron and the cochineal and remixed them with water, and then filtered them again. The result was a orangish coral color. This was added to the remaining dye in the pot that had been only the black oak bark. This was slowly heated while the flammegarn was prepared with more ties. This new dye bath now contained the exhaust of the cochineal and quercitron, the tin added in the last five minutes of the original cochineal dye bath, and the gypsum and piece of copper pipe. Once this bath reached about 180 F, the flammegarn was immersed into the bath. Here it remained about 10 minutes, was removed, and then dipped into ammoniated water (about 1 part ammonia to 24 parts water – 1/2 c. to 3 qts. of water). After the dip, I rinsed the yarn in clear water and spun it out in the washer before hanging the hanks up to air dry outdoors.

It’s in the water.

The water here in Thousand Oaks has a pH of 8. This means it has a slightly alkaline quality. The use of gypsum is to move the water closer toward pH 7, which is neutral. Ammonia is alkaline, and pushes cochineal toward the purples, and the tin in the dye bath helps to promote the red qualities of the cochineal. With the golden underdye of the quercitron, the overdye of the two exhaust baths created a color similar in tone to the gold. The result is a color variation in the yarn ranging from pale gold, to darker gold, corals and pinks.

Voila!

The final results are below. The colors are a bit lighter, but the photograph does a good job of showing the true colors. My camera pushes yellows and oranges toward the reds, and makes them far too intense at times. If you click on the photo, you should be able to see the skeins in a larger photograph, which will help you get an idea about how they look in real life. Bigger is better, here! These skeins most likely will become my own pair of flammegarn socks, either with a 2×2 rib for the ankle, or plain knitting, unless I create a little scarf with some plain knitting combined with lace.

Natural Dyeing: Mordanting

Setting Up

It is a bright, crisp spring morning, perfect weather for mordanting outdoors. The stainless steel dyeing pots have been pulled out, scales, yarn, alum and tartaric acid, buckets, goggles, gloves, basins, buckets, towels, thermometer, mixing bowls and spoons. First to be set up was a kettle of water to heat on the burner. Next, 100 g. of wool weighed out, and set to soak in hot water. On the smaller scale, a plastic bowl was set down, and then turned on to set the tare weight to zero. 5 g. tartaric acid weighed and emptied into a stainless steel bowl. 10 g. alum weighed out, and added to the bowl with the tartaric acid. Hot water added to this to dissolve the crystals. Meanwhile, I continued to organize a few things as the water heated.

Weighing

Having two different scales, one for large items and one for small, is great. These are the scales Josh uses in brewing, to weigh grain and hops. The large one does both pounds and kg and g, while the other one does tenths of a gram, along with other weighting systems.

Traditional natural dyes have an alum-to-wool weight ratio of 1:4. This means for every pound of wool, 1/4 lb. alum is to be used, or for every 100 g. of wool, 25 g. of alum is to be used. Most books warn you not to use too much alum as it makes the wool sticky. It does, and it is a really disgusting feeling. Nor can you fix the problem.

Trudy van Stralen, author of Indigo, Madder, and Marigold recommends using a 1:10 ratio of alum to wool, and a 1:20 ratio of tartaric acid to wool. Now, trying to figure this out in pounds is absurd, and this is where the beauty of the metric system really shines. It means for 100 g. of wool, the alum proportion is 10 g, and the tartaric acid is 5 g. If this is confusing, just think of it in terms of U.S. money – $1.00 = 100 g, a dime is 10 g., and of course a nickel is 5 g.

Van Stralen also recommends using the same water and the same solution for subsequent batches of wool, saving time in heating up water, and saving money by only adding 5% more alum and 2.5% tartaric acid back to the mordant bath. Appeals to me!

Mordants-to-Wool Ratio

My first batch of mordanting wool had plenty of room in the kettle, so for the second batch, I weighed out more wool. This time it was 260 g. Using the 10% rule would give me 26 g. of alum; the 5% rule of tartaric acid would be 13 g. Given the idea that there is essentially 5% and 2.5% of alum and tartaric acid respectively remaining in the mordanting kettle, I went with an approximation of 7.5% for the alum, which was 20 g, and 3.75% for the tartaric acid, which is 10 g. I added these to the mordant water to accommodate the larger amount of fiber. I still won’t have 25% alum to wool in weight, so there should be no stickiness problem. The rest of the wool will be weighed out in 260 g batches, so it should go more quickly. If I didn’t do this, I think I could easily spend the whole day mordanting; I’d rather do it in half the time!

For all of these, the water is not boiling, but holding steady at about 200 F. The wool skeins did not get agitated by roiling water. The commercial skeins have held their crisp twist, and the handspun ones did not exit the mordant bath any more felted than they were prior to entering it.

Premordanting for Indigo?

I don’t have any idea if indigo will be affected by an alum-tartaric acid premordant, but as I figure I will be overdyeing some of my future indigo wool with quercitron, for green, and cochineal for purples, premordanting the wool could only help. That is something to be seen in the future.

Comment

The last time I used natural dyes and mordants was ages ago. I used pounds and ounces, cups and teaspoons. The metric system is far easier than the English system! I am looking forward to the results as van Stralen uses a higher concentration of dyestuff to goods; this is my plan for this adventure.

I really like van Stralen’s book because of the clear and colorful illustrations. My own small dyeing library has old and new books in it. The different approaches to mordanting and to dyeing are interesting to read, as are the approaches to dyeing.

I’ve done the one-pot-dye-and-mordant approach, which is really time efficient, but perhaps not efficient in the use of chemicals and dye materials. There is also the added nuisance of having to pull twigs and flowers out of the wool. I am hoping to avoid this, and am trying to decide if I should get some mesh bags to contain the dye materials if I cannot grind them up finely enough.

A lot of the books from the 70s use the all-in-one method. Liles book is very specific. Others are vague. For Californians, Ida Grae’s Nature’s Colors is a must-have – too many books seem to think that the entire U.S. lives on the east coast!

This round of natural dyeing is a bit more systematic compared to my usual approach to dyeing. I’m interested in seeing the results of this. Because there is time involved here, it makes sense to heed what I am doing. And, as it is also an artistic experience, I find myself contemplating what I might do with this batch of yarn or that. For instance, the Shetland is being considered for – what else? – a Shetland sweater vest. This means I can use colors and more colors, but there will be (in theory) an underlying harmony from both the moorit fleece, and the natural dyes themselves.

Final Notes

Before you begin any dyeing – natural, unnatural – I cannot emphasize enough the importance of skeining your yarn properly. Even if it comes in a commercial skein with a few ties, it most likely will not be enough. I tied off a few extra figure-eight ties on the Sea Wool, but that was not sufficient. Some tangling resulted. For my handspun, I did my usual, and placed eight ties throughout the skein. My skeiner creates skeins which are 1 yard long, so I have six feet to play with. I find that I can have very minimal tangling if I adhere to eight ties, and 3 figure-eights per tie. A lot of work, but it is more work to untangle a skein. The alpaca and Blue Faced Leicester, being very fine yarns, probably should have had even more ties.

Below is a table of my weights of fiber and mordants. This could be a handy thing for me to refer to later on!

Batch	Wool Weight (g)	Alum Weight (g)	Tartaric Acid (g)	Comments
1	105 Sea Wool	10	5	10% / 5% for initial pot.
2	260 Sea Wool	20	10	Did 7.5% / 3.75% as this was a larger amount than put in pot. 200^oF.
3	215 handspun, alpaca, Blue Face Leicester	11	5.5	Pot boiled. Skeins got tangled. 5% / 2.5%. 200^oF.
4	220 handspun moorit Shetland	11	5.5	Came out nice. 5% / 2.5%. 200^oF.
5	280 handspun moorit Shetland	14	7	Water color rather lightly olive colored. 5% / 2.5%. 200^oF.