Madder – Madder is one of the oldest known dyestuffs. It is used to produce turkey reds, mulberry, orange-red, and terracotta. In combination with other dyes madder can give crimson, purple, rust, browns, and near blacks. By manipulating mordanting, pH, and temperature a range of shades can be obtained. There are many historic recipes including one from Turkey which brings out the purpurin from madder resulting in a purple.
Mordanting: Use alum mordant at 15% WOF for protein fibres. For cellulose, first mordant with tannin at 8% WOF, then either 1) use alum at 15% with soda ash at 2% or 2) use aluminum acetate at 8%. For deep brick reds on cellulose choose the aluminum acetate at 8%.
Dyeing with the extract: Use at 3-8% WOF for a medium depth of shade. To achieve reds and avoid browns keep the dyebath under 180°F (82°C).
Dyeing with the powdered roots: Madder is dyed at 35-100% WOF for a medium to dark depth of shade. Madder develops to its deepest and richest reds in hard water – water containing calcium and magnesium is ideal. If the water is soft add calcium carbonate (a single Tum’s tablet to 4 litres of water works well). Add dye material to dye pot and cover with water. Bring up to about 60ºC (140ºF) and hold for an hour. Add fibres and continue cooking for another 1-2 hours.
Rubia cordifolia: Munjistin is the primary dye molecule, it gives the famous reds found in Indian chintz and painted cottons. Also present in the roots are small quantities of alizarin, purpurin, as well as many yellows and browns. Rubia cordifolia is not as affected by high temperature. The madder dyebath can be reused two or three times for lighter shades.
Options: Madder, in combination with cochineal yields a true red, with iron yields garnet, bright orange with alum and cream of tartar, brick red with alum mordant and a higher heat (cordifolia only), the addition of acetic acid or vinegar plus iron will push the colour to a rich brownish-purple.