Cochineal
Dactylopius coccus
Cochineal is the most important of the insect dyes. The females of Dactylopius coccus colonize the prickly pear (nopal) cactus native to Mexico, Central and South America and the Canary Islands. Peru is currently the primary export country, shipping out over 4000 metric tons annually. This dye is a common additive to food, drugs and cosmetics. Cochineal has excellent light and washfastness and produces a powerful range of fuchsias, reds and purples. Although expensive, cochineal has a high concentration of carminic acid and only small amounts are needed.
See the MAIWA GUIDE TO NATURAL DYES
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%.
Dyeing with the extract: Use at 0.5 to 2% WOF for a medium depth of shade.
Dyeing with the bugs: Only 3-8% WOF is needed for a medium depth of shade. The colourant is first extracted from the dried insects as follows: Gently grind the insects in a blender or use a mortar and pestle to crush them to a fine powder. Put this powder into a saucepan and cover with three inches of water. Boil for 30 minutes. Strain the liquid and set aside. Place the cochineal pulp back in the saucepan and again cover with water and boil for 30 minutes. Add this decanting to the first decanting. Repeat 2 more times. Some dyers will then keep the remaining pulp in a jar of water for several weeks and use it for future dyebaths.
The combined decantings are used to make a dyebath. Because Cochineal is sensitive to acids and bases soaps used to pre or post wash your fibres must have a neutral pH.
Options: If cream of tartar at 6% WOF is added to the alum mordanting bath or the dyebath, the colour achieved will be more towards Christmas red. With the addition of iron at 2-4% WOF to either the mordanting bath or the dye bath the colour will shift towards purple. Cochineal can be shifted to orange with the addition of an acid (citric acid) and to a deep fuschia with the addition of an alkaline (soda ash).
Below: Cochineal Bugs 8% WOF
Below: Cochineal Bugs 8% WOF with 6% cream of tartar
Below: Cochineal Bugs 8% WOF and Iron 2% WOF
Below : Cochineal Bugs 8% WOF and Madder 30% WOF
