Tattoo Ink: Making a Lasting Mark

After picking a design and seeing it take shape, nobody wants their new tattoo to wash away. Check out Groupon’s examination of how the ink manages to last.

Insoluble tattoo ink, which consists of pigment suspended in a carrier solution such as water or alcohol, isn’t a modern marvel. Archaeologists have found tattoos on Egyptian mummies that date back roughly 4,000 years. In so doing, they've revealed two things: that the practice of tattooing has existed for millennia, if not longer, and that a single tattoo can last a pretty darn long while. To achieve that permanence, the ink distributes colored metal salts, vibrant plastics, or even vegetable dyes evenly within the solution, making it easy to insert into the second layer of skin, roughly a millimeter below the surface, where it remains safe from the upper layer’s constant flaking. Like paint, today’s inks can be mixed and diluted into a spectrum of shades and colors—even glow-in-the-dark varieties for tattooing a map of the route to the bathroom from your bed onto your arm.

Along with the Egyptians, other historical humans had their own tattooing methods. Inuit tribes, for instance, would pierce their skin with needles and draw soot-covered threads underneath the skin. Modern techniques are much safer, although the process still carries risk. Some people may exhibit allergic reactions to certain pigments, and some pigments can cause irritation in sunlight. If you commonly have reactions to cosmetic products, look into using hypoallergenic inks before going under the gun.