11.04.2011 § 2 Comments
Many people think that natural dye would be environmentally friendly and that “green” products should use natural dye. Let’s consider some facts about natural dyes.
Natural dyes have poor color power, meaning that a large amount of dye is needed to produce deep shades. Natural dyes have poor color fastness to laundering and sunlight too. Even indigo dye — which has a pretty good output — is not powerful enough to supply today’s demand. Last year, I heard a professor in a class quote a study saying, “It will take 80% of US arable land to grow indigo in order to supply the blue jeans consumed in the US.”
Cochineal is a female insect that is native to South America and Mexico. A bright red color is extracted from the insect and was probably used to dye the British red coats during the Revolutionary War. It takes approximately 70,000 insects to produce one pound of dye.*
As many also know, the Mediterranean conch that produced Tyrian purple from its secretions is now extinct. The Romans loved the brilliant purples, but ideas of stewardship did not exist then. If the Tyrian conch were still in existence today, would we want to extract the dye and perhaps eat the meat? How about the shells? Maybe one could sell them in a souvenir shop for decoration.
* Source from College of Textiles, NC State University, Raleigh, North Carolina.