Carbon black, a pigment derived from petroleum, is commonly used to create black for everything from clothing and phones to cars and ink. It comes from tracts of land called tar sands, that are stripped of all life and vegetation to extract the heavy petroleum.
Clothing maker Vollebak, based in London, England, has been using black algae to offer a more sustainable alternative to carbon black. It used the dye to create the first T-shirt dyed with algae.
Colorado-based manufacturer Living Ink makes the dye, which is created by heat-treating algae biomass to turn it into a blackened char, which locks away the carbon that was sequestered by the algae throughout its life. This creates a concentrated black powder pigment that Living Ink says is carbon negative. The most challenging part of creating black algae dye pigment is creating individual particles of pigment that are microscopically small and very black. Making ink from black algae pigment is easier because it can be made with larger particles. Living Ink’s technology produces a pigment that’s fine enough to use as a dye pigment.
Vollebak is already working on the next version of its clothing to achieve a more intense black color, as the current version is more of a dark gray. The goal is to ultimately match the color that carbon black can produce.