Dissapearing Ink to Cut Cost of Printing

Energy conscious scientists have developed a new type of vanishing ink which disappears completely after 24 hours allowing the paper to be reused up to 30 times as long as its intact and not creased.

The not so aptly named ink is actually a discolouration of light-sensitive molecules know as photochromes. The paper is coated with photochromes and when they are exposed the ultraviolet light the molecules turn a dark shade of purple. As soon as the molecules come into contact with warm air the writing begins to fade away.

The developers say that the ultra-violet units could be easily incorporated into a standard printer and the cost of the molecule-coated paper is similar to the cost of normal paper.

Recent studies have shown that 45 percent of printing is for one time use with most of it used for reading emails and then being turfed into the recycling bin.

The new ink has also proven to be more energy efficient way of printing than printing on regular or recycled paper. With it taking 110kj of energy to print on recycled paper and just over 200kj to print on normal paper, the amount of energy needed to produce one page of vanishing ink print differs by a factor of 200 at just 1kj per page.

The disappearing was demonstrated by Xerox representative, Paul Smith, in Grenoble, France however it is likely to be several years before the technology is commercially marketed.