No Need for an Eraser: Rewritable Paper is Here

Rewritable paper that does not use ink but instead uses dyes that respond to ultraviolet light has been developed by U.S. scientists. The dyed paper may be a solution to growing environmental problems associated with the use of regular paper.

Scientists at the University of California, Riverside, created the rewritable 'paper' by covering a plastic film with the redox dye methylene blue and adding a titanium dioxide catalyst. They then created photomasks that only allowed ultraviolet light through in specific patterns such as images or blocks of text.