Scientists have created hair dye from graphene. The hair strands were coated in a layer of graphene roughly 2 microns thick (human hair is generally 10 to 200 microns thick)—and it stayed on even after 30 washes.

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Scientists have created hair dye from graphene. The hair strands were coated in a layer of graphene roughly 2 microns thick (human hair is generally 10 to 200 microns thick)—and it stayed on even after 30 washes.