Real solar dyeing with food coloring & vinegar
This is my first experiment with solar dyeing. Most of the books and websites that discuss “solar dyeing” are really talking about sun tea-like steeping in large glass jars. That process does not produce enough heat to fully set most dyes. You need temperatures of 180–190°F / 82–88°C to set most dyes, especially acid dyes for protein fibers and many natural plant and insect dyes for cellulose and protein fibers.
I want to use solar cookers to replace stovetop steaming, oven steaming and crockpot dyeing methods. As I mentioned in post a few days ago, solar panel cookers have cooking temperatures of 200–300°F / 93–149°C. Because I used food coloring as the dye and white distilled vinegar as the mordant, I used a three liter solar cooking roaster and my CooKit™ panel cooker.
I decided to dye a thrift store skein of white wool. It weighs 2.35 oz/67 g. I presoaked it in a stainless steel bowl for 45 minutes in a solution of water and a couple of cups of vinegar. I spun it out in a salad spinner, also from a thrift store, so that the fiber would be damp, but not wet. I spread out a piece of newspaper and a layer of white paper towels. This turned out to be inadequate to catch all the water in the dye solutions. I have some old bath towels I use for wet felting, but they are forest green. I will buy some white towels the next time I go to a thrift store (I want to be able to see the dye mess).
I made up four dye solutions, the first one in a glass jar, the rest in specially-made dye squeeze bottles with tight caps and small orifices:
- 25 drops each regular green and neon blue + 1 ½ cups of water (my main dye solution)
- 10 drops neon purple + ¼ cup water
- 10 drops neon blue (plain blue) + ¼ cup water
- 10 drops regular green (green + a little blue) + ¼ cup water
I could have also used drink mixes like Kool-Aid, which also contain their own mordant, citric acid.
I wanted to use the main aquamarine color for most of the skein. I first tried using an eye dropper to apply the main dye color, but it seemed too slow so I switched to dip dyeing sections of the skein into the jar and squeezing it out (while wearing rubber gloves). I then layed the skein on the towels. I applied the three accent colors to the white areas left on the skein. I finally added some yellow stripes directly out of a food coloring bottle on top of a couple of green areas. I had just enough squeeze bottle dye, but twice as much of the main dye solution as I needed, so I screwed on a lid, applied a label that says, “food coloring dye” and put it in the refrigerator.
I put ¼ cup of water in the bottom of the roaster and then a metal trivet. I didn’t want the metal to affect the final yarn colors so I added a layer of parchment paper on top. I gently squeezed out excess moisture from the skein, being careful not to let colors bleed into one another too much. I folded the skein in two and layed it in the roaster with the two purple areas together (to prevent color bleeding into adjacent aquamarine areas).
I set up the CooKit™ on my driveway just like I did the other day to cook rice at 12:30 p.m. The books and websites I had consulted beforehand said to steam hand painted skeins for 45 minutes. Because there were a few clouds on a mostly sunny day, I left the pot in the cooker for two hours. Solar cookers require adding a heat up time to the steaming time.
I removed the pot, brought it upstairs and left it to sit four hours. Then I rinsed the yarn in a soap solution. I spun out the water in the salad spinner. The rinse water was almost completely clear, with just a trace of yellow. I hung up the skein to dry overnight. I am very happy with the colors.
The purple turned out really well. I had heard that purple food coloring easily separates into its constituent red and blue pigments because their uptake times differ, but I think my cold application method and steaming method (as opposed to immersion dyeing) prevented too much color separation. I liked the purple so much that I went online and bought some specialty AmeriColor™ food coloring gels in shades of fuchsia/magenta/maroon, royal purple/violet/neon purple and turquoise/jade greens from the Layer Cake Shop.
Now I really want to build a large solar panel cooker so I can dye skeins without lying sections on top of each other, dye larger amounts of fiber/yarn at once, do solar immersion dyeing with cochineal, and dye with non-food safe dyes like Procion MX for cotton. I need to do some research on my options. I have some ideas about panel materials.