Mordantointi

Mordantointi is a Finnish term that refers to the process of mordanting, which is a crucial step in dyeing, particularly with natural dyes. A mordant is a substance, typically a metallic salt, that helps to fix the dye to the fiber. Without a mordant, many natural dyes would wash out easily or not adhere to the fabric or yarn at all. The mordant forms a coordination complex with the dye molecule and the fiber, creating a stronger bond that results in a more permanent and vibrant color. Common mordants include alum (potassium aluminum sulfate), iron (ferrous sulfate), copper (copper sulfate), and tin (stannous chloride). The choice of mordant can significantly influence the final color obtained from a particular dye. Different mordants can shift the hue, increase the intensity, or improve the lightfastness and washfastness of the dyed material. Mordanting is typically done before the dyeing process, although sometimes it can be combined with the dyeing bath or done after. The fabric or yarn is usually soaked in a solution of the mordant for a specific period, then rinsed before being placed in the dye bath. The process requires careful attention to concentration, temperature, and time to achieve the desired results and to ensure safety, as some mordants can be toxic.