Mordants are part of the dyeing process and help achieve vibrant colors. Dyeing fabrics goes back to the Stone Age. Mordants are also used for dyeing stones such as quartz, one of the essential techniques of ancient alchemy. Dyes are a big part of early trade and commerce.
What are Mordants?
Derived from the Latin word mordere, meaning “to bite,” mordants essentially "bite" the dye into textile, ensuring it adheres. Mordants fix colors onto fabrics or other materials, creating a strong connection between dye and fabric. Without mordants, dye colors quickly fade.
Importance of Mordants
Color Retention (fixation): Mordants help the dye molecules bond with the fibers of the fabric. Mordants help maintain color and improve wash-fastness and light-fastness of dyed fabrics.
Color Variability and Enhancement: Different mordants can yield different shades from the same dye, allowing variety and control over the final color.
Sustainability: Using natural mordants (and dyes) is a sustainable choice.
Mordants fall into different categories based on chemical composition, including:
Metallic: alum (potassium aluminum sulfate) is the most popular of metallic mordants. Alum is widely used as it creates bright and lasting colors. It works well with different fibers and is still used today in natural dyeing.
Earliest evidence of alum is in Mesopotamia. It's applied as a mordant for madder dye. Use of alum in Egypt starts c. 1500-1000 BCE.
Iron (ferrous sulfate aka copperas, green vitriol): this mordant darkens colors. Iron mordants are often used to shift the color of dyes towards black or gray shades. It can also weaken the fabric if overused. Ferrous sulfate is common at gardening stores.
Tannins: Natural compounds found in many plants, including oak galls and sumac, serve as mordants by forming complexes with dye and fiber. Tannins are natural mordants and most effective with cellulose fibers like cotton. Tannins create softer, muted colors.
In ancient and medieval times, stale urine is also used as a mordant. Each type of mordant can yield different shades and intensities within the same dye, allowing for home and market flexibility. While metallic salts like alum are effective, table salt NaCl is no good as a mordant.
Dyeing with a Mordant
Prepare the Fiber
Ancient artisans follow a specific dyeing process. First, the fabric is prepared by washing and soaking to remove any impurities.
Before applying dye, fibers such as cotton, wool, silk or even paper need to be prepped. This is basically washing to remove any oils or finishes, which allows the mordant to bond more effectively with the fibers.
Apply the Mordant
The chosen mordant is mixed with water to create a solution. This can be done through boiling or steeping, depending on the type of fiber and mordant used. The material is then immersed in the mordant solution for a specific time, allowing it to absorb the mordant.
This process can take 8-24 hours. The fabric may trap air which must be forced out of the cloth. Weigh down fabric with clean objects if necessary. The mordant container is then lidded and the contents left to soak, occasionally stirred. It doesn't need heating.
Dyeing:
Once the fabric has absorbed the mordant, it's rinsed and then immersed in a dye bath. The mordant reacts with the molecules of the dye, strengthening its bond with the fibers. This creates richer colors less likely to fade or wash out over time.
Dye can be applied either in a dye bath or by using various other methods like tie-dyeing or fabric painting. The process can be repeated as desired.
In recent years, a renewed interest in natural dyeing and mordants arises due to growing focus on sustainability in the textile industry. Artisans and eco-conscious dyers revive ancient methods using natural materials to reduce environmental impact compared to chemicals.
Non-Fiction Books:
Fiction Books:
READ: Lora Ley Adventures - Germanic Mythology Fiction Series
READ: Reiker For Hire - Victorian Detective Murder Mysteries