Creators at Living Ink Technologies have created an eco-friendly “timelapse” ink that magically appears after exposure to sunlight.
The plant pens contain cyanobacteria, algae and chlorophyll in tiny amounts that are invisible to the naked eye at first. But when exposed to sunlight, the organisms reproduce at astonishing rates, bolstering their numbers to the point where they finally appear dense and green, thanks to the chlorophyll that harvests light energy and reflects light.
There are two types of ink: pink or “fast ink” which grows in 1-2 days, and blue or “slow ink” that takes 3-4 days to appear. This allows you to create a two-stage secret reveal over the course of a week which could find use in greeting cards or even a proposal!
The creation is housed inside a compact ‘greenhouse’ (which doubles as a picture frame) filled with a nutrient-dense material called agar that promotes the ink’s growth. When removed from the frame the algae and bacteria will eventually die, but the resulting image stains the paper so that it won’t fade away.
Besides being fun, Living Ink is also nontoxic. “Carbon black is the most common pigment used in black inks. It’s most commonly made from the incomplete combustion of heavy petroleum products such as tar,” says the company, who sidestepped this by making its product out of the ultimate organic material — living organisms.