Scientists have developed self-destructing messages using printer ink that vanishes after 24 hours.
When the document is printed on the reusable paper, it appears in a shade of dark purple however it fades until it has gone completely. The Scientists hope that the technique will reduce the trillion pages put in the recycling bin soon after being printed each year.
According to a press release from Xerox, the ink is a temporary discolouration of light-sensitive molecules known as photochromes. The paper is coated with photochromes, which change colour when they are exposed to ultraviolet light. Whe the printing is finished, the molecules begin reacting to the warmth in the surrounding air and gradually return to their natural state.
So long as it is not creased, the paper can be used up to 30 times.