Natural Dye
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.
Woven-Words 
You make some good points about the use of natural dyes but I would like to comment. True that indigo could not meet today’s commercial demands, but there are still good reasons to use it. Its production often supports rural communities in a way chemical dyes cannot and producing natural dyes is far less toxic to the worker’s environment. Indigo and other natural dyes do fade over time but many experts say they in fact become more beautiful, developing a patina-like sheen. Synthetic dyes eventually fade as well but don’t maintain any beauty. But in the end, it doesn’t really matter because from an environmental point of view, the real problem with supplying the commercial market is simply that people consume too much and discard too easily. There seems to be little concern for making clothing last. Yes, natural dyes cost more – the whole process is more labor intensive but perhaps if someone paid more for a pair of jeans (many already pay premium price just for a brand name) they would take more care.
In India, there is a lot of effort being made to produce natural dyes for the commercial market. I import some of these – they are made using a fermentation method and a little goes a long way compared to using just the dried plant material. The color and light-fastness is outstanding and there is a full range of color available using only plant material rather than any animal base such as cochineal. And much of this plant material would otherwise be waste, such as pomegranate skins.
One advantage synthetic dyes have is they can be used on synthetic materials which the commercial market has also become very dependent on. But that’s another discussion.
Thank you for your comments. On an artistic level, I agree, nothing compares with natural dyes. They’re truly beautiful. Commercially, though, there’s a misconception that something that’s natural is also sustainable. As you pointed out, demand is very high, and natural dyes can’t always keep up. It’s a difficult balance.