Erasable Paper

At the Palo Alto Research Center, scientists are developing a way to print an image that disappears, allowing paper to be used dozens of times.

The experimental printing technology, a collaboration between the Xerox Research Centre of Canada and PARC (Palo Alto Research Center Inc.), could someday replace printed pages that are used for just a brief time before being discarded. Xerox estimates that as many as two out of every five pages printed in the office are for what it calls "daily" use, like e-mails, Web pages and reference materials that have been printed for a single viewing.

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