Yarn Dyeing: techniques and tips
Have you ever been captivated by the breathtaking colors achieved through dyeing yarn? Today, we'll delve into the intriguing world of yarn dyeing and explore two primary types of dyes: acid dyes and natural dyes.
But before we delve into the dyes themselves, let's start with a brief explanation of the structure of wool and other protein fibers. Protein fibers, including wool, cashmere, silk, and mohair, are predominantly made of keratin, the same compound found in hair and nails. This composition makes protein fibers strong, resilient, and ideal for dyeing. These fibers possess a protective outer layer called a scaly cuticle, which slows down water absorption. That's why presoaking your yarn is a crucial step in the dyeing process.
During presoaking, water permeates the yarn's core, allowing for even dye absorption through a process called diffusion. Diffusion occurs when molecules move from areas of high concentration to low concentration. In the case of dyeing, dye molecules migrate from outside the yarn to the interior, bonding with the fiber at the membrane, a layer beneath the outer cuticle.
A special note about dyeing with superwash yarn: Superwash yarn undergoes a treatment to prevent felting when washed. Regular yarn with a scaly cuticle can bind to itself during agitation, causing felting. Superwash yarn addresses this issue by smoothing the outer layer, making it more receptive to water and dye. If you're new to dyeing superwash wool, it's advisable to test a small amount before dyeing an entire skein.
The bond between dye and protein fibers is formed due to the presence of twenty amino acids in the fiber's composition. These amino acids primarily engage in ionic bonding with the dye pigment. Ionic bonds occur between oppositely charged molecules, much like how North and South magnets attract and stick together. This is how dye molecules bind to the fiber. Once the right conditions are created, the dye bonds with the fiber, resulting in a vibrant, hand-dyed skein of yarn. Since all Knomad yarn blends contain at least 50% protein fibers, the methods discussed below can be applied to your favorite Knomad yarn skein!
Acid Dyes
Acid dyes are an excellent choice for dyeing any protein fiber. The term "acid" in acid dye refers to the environment necessary for the dye to bond with the fiber. Whether you're using commercially produced dye, food coloring, or even Kool-Aid, adding acid to the dye bath is crucial. Common acids used are white vinegar or citric acid crystals. These acids lower the pH of the dye bath, enabling the dye to bond with the fiber at a molecular level. Heat also plays a significant role when working with acid dyes. The combined effect of heat and acid agitates the fiber molecules, facilitating their bonding with the dye molecules. When all the dye molecules have bonded to the fiber, the dye bath becomes clear, indicating it is "exhausted."
Natural Dyes
Natural dyes encompass dye sources that occur naturally. Often, you can find these materials in your kitchen or garden, such as avocados, turmeric, pokeberries, and red cabbage. The key difference between acid dyes and natural dyes is that natural dyes typically require the use of a mordant to fix the color instead of an acid. One exception is avocados, which naturally contain tannins that act as a mordant and assist in forming ionic bonds with the fiber. The term "mordant" comes from a Latin word meaning "to bite." Commonly used mordants include alum, copper, and iron salts.
Mordants help the dye pigments form the necessary ionic bonds with the amino acids in the fiber. However, some mordants may alter the color of the dye bath, so it's essential to conduct small tests in advance. The pigment extracted from a natural dye bath can shift with the addition of an acid or a base, which can be advantageous when creating a dye bath. However, when rinsing a naturally dyed skein, be sure to use pH-neutral soap to prevent color shifting after dyeing.
To create a natural dye, extract the dye from the dyestuffs by simmering the material while presoaking the undyed yarn. Then, strain the dyestuffs out of the bath. You can presoak the yarn with a mixture of water and your chosen mordant or directly add the mordant to the dye bath along with the yarn. Add the yarn to the dye bath and simmer until the desired color is achieved. Afterward, cool the yarn, rinse it thoroughly, and let it dry.
Now that you're aware of the science behind dyeing yarn, each time you dye a skein in your pot, new ionic bonds will form, resulting in a unique, hand-dyed creation.