Indigo Dyeing With Quilty Friends

My guild did it's in person meeting in August at a member's home and we did indigo dying. Indigo can dye all natural fibres. It gives beautiful shades of blue — from the palest summer sky to an almost purple black. The colour achieved depends on the type of vat, the concentration of indigo, and the number of dips. Indigotin (the dye component of indigo powder) is insoluble in water. To use it for dyeing it must be reduced to a water-soluble form. All indigo vats need three things: 1) Indigo 2) A reducing agent 3) A Base. Chemically, we need to reduce the indigo to make it soluble — we do this with a reducing agent. Reducing agents can be sugars, some natural dyes or other plants, or chemicals. A reducing agent lowers the oxidation state of the indigo molecule, transforming indigotin into leuco-indigo — which is soluble in water at room temperature. If we just add powdered indigo to water it will remain in pigment form, suspended but not dissolved. What is the difference between a suspension and a solution? A fish is suspended in the ocean. But salt is dissolved in the ocean. You can see the fish (which remains distinct) you cannot see the salt (which has dissolved). If we can see the indigo (the dye bath is blue inside) then the indigo is not dissolved and the dye bath cannot be used to for dyeing. When the indigo is reduced it dissolves and the dye bath is a greeny-yellow colour. We had so much fun with all the various iterations that we produced that we are eager to do it again next year.