Mordants and Assists
Successful dyeing with natural materials and natural extracts requires that the natural fiber be prepared by cleaning, preparing and mordanting before applying the dyestuff: Orvus paste, soda ash, scour, aluminum acetate. aluminum potassium sulfate, sodium acetate and tannin. Some dyeing assists will change the color primarily by shifting the pH of the dye-bath: chalk, citric acid, cream of tartar and iron. The indigo vat requires its own group of modifiers to prepare and maintain it for dyeing blue: fructose, hide glue, lime, lye, pH strips, and thiourea dioxide. Gum tragacanth is used to thicken dyes for painting on fiber