Acid dyes are the most common type of dye used on fiber and yarn. Acid dyes can sound intimidating because of the “acid”, but they are actually very easy and safe when used properly. They are called acid dyes because a weak acid is added to the dye bath to cause the dye to strike, or adhere to the fibers. Vinegar and citric acid are the two most common acid used in home dying.
Acid dyes are suitable for use on protein fibers, which are animal fibers such as wool, angora, alpaca, mohair, silk, etc. Acid dyes also work with some plant fibers, such as bamboo. Nylon is the only synthetic fiber I know of that will work with acid dyes. Fortunately, synthetic fibers aren’t very commonly used for spinning, so this isn’t really a problem.
Food dyes can be used as acid dyes and are very safe. They are a good way for a beginner to try dying without spending a lot of money on specialized dye and equipment. Regular food coloring will work, but the colors aren’t very concentrated, so I do not recommend them. Easter egg dyes (the regular PAZ tablets) work very well, but they are expensive, unless you can get them on clearance.
Wilton’s icing dyes work well and are very inexpensive (around $2 a jar at Hobby Lobby). The only downside is that some of the colors are composites, and different colors strike at different rates, so they do not dye very evenly. Sometimes, the mottled colors look pretty cool though. (If any members would like to try using Wilton’s dyes, please email me privately. I have a bunch of extra jars I would be happy to send your way.)
In my opinion, the very best food type dye that can be used for home dying is Kool-Aid. Kool-Aid is very easy to work with and cheap. Kool-Aid colors mix very well with each other and strike very evenly. In my experience, the dye is also very light-fast (doesn’t fade with exposure to sunlight).
I generally use Jacquard Acid Dyes or Lanaset/Sabraset dyes. These are professional dyes which require some safety precautions. They are both toxic in their powder form, so I mix dye stock to keep on hand so I don’t have to work with the powder as often. When I mix my dye stock, I do it outside, away from wind, and I wear a dust mask and gloves. I store the dye stock in mason jars so that it is ready when I want it.
I use 2tsp of dye for each quart of boiling water. I treat this as a 1% solution (1 gram of dye to 1 ml of water) even though it probably isn’t all that precise. It’s close enough for my dye work. When I mix dye stock, I always use the same ratio, it’s easier to recreate colors. This makes it very easy to measure the proper dye ratio to achieve the desired depth of shade.
Dye stock is best stored in a cool, dark place. The colors will sometimes separate while stored, but you can just shake them up to remix them and they work fine. If dye stock is stored too long, it can mold, so it is best not to mix large batches if you don’t think you will use the dye within a few months. Also, if the dye stock freezes, it’s never really the same again.
With proper safety precautions, working with these dyes can be safe. When dying I:
- Avoid inhaling dye powder by using a dust mask
- Work in a clean environment. My kitchen is my dye studio, so I make sure to put away anything that may be used to cook food.
- Use specific pots and utensils that will never again be used for cooking
- Work in a well ventilated area
- Clean thoroughly afterwards
I use two different processes to dye fibers depending on the results I am looking for. If I’m looking for a uniform color, I use the immersion method. If I’m looking for a variegated result or using more than one color, I paint the fibers. The dye process I use with Kool-Aid is identical to the process using Jacquard or Lanaset dyes.