PARC (Palo Alto Research Center Inc.) has invented an experimental printing technology (pdf) that can erase and reuse paper up to 100 times and that could someday replace printed pages that are used for just a brief time before being discarded.The paper contains specially coded molecules that create a print after being exposed to ultraviolet light emitted from a thin bar in a printer. The molecule readjusts itself within 24 hours to its original form to delete the print, or heat can readjust the molecule instantly. Xerox developed the molecule The ultraviolet bar itself is very small, so it can be used in mobile printers. The technology could also be useful for network printing. For now, the technology prints effectively only in black and white. Although good for everyday prints, ink remains a better option for high-quality prints. Shrader couldn't project when reusable paper or UV printers would reach consumers.
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. The scientists are developing compounds that change color when they absorb a certain wavelength of light but then will gradually disappear. In its present version, the paper self-erases in about 16-24 hours and can be used multiple times.
A very worthy invention indeed !
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