UK scientists build the 'un-printer'

You've had a printer help you print reams of paper for that important presentation, and now, you have an un-printer, to help you wipe out all that text (no kidding!). According to a report in New Scientist, an engineering team at the University of Cambridge, UK have devised a method, which can potentially wipe a paper that has been printed on, clean without any noticeable degradation in the paper, in the process. The system to do so essentially uses a laser-based technique, which erase the text on the pages by vaporizing common toners. The laser-based technology ensures that while the text gets sufficiently erased, till the point the paper looks new, the paper will not degrade in quality. Result? You get in your hand a bundle of paper - fresh, ready-to-be-printed upon, and re-used.

The scanned electron micrograph showing where

The scanned electron micrograph showing where" paper cellulose has been exposed by the beam"



Deforestation has been one of the biggest worries that man has been facing, ever since he decided to embrace industrialization wholeheartedly. Paper making industries, among several others have been actively consuming wood to keep their production going. Corporations, the world over are doing their bit at promoting "save paper" reminders, too. Now, David Leal-Ayala and his colleagues at the University of Cambridge have made this whole deal a lot sweeter. Interestingly, Japan-based company, Toshiba, according to this report already has a special laser printer/copier selling in the market (watch a video of it, here), which uses a blue toner, which with heat treatment can be almost completely erased. 


Quoting him, the report adds that, "The key idea was to find a laser energy level that is high enough to ablate - or vaporise - the toner that at the same time is lower than the destruction threshold of the paper substrate. It turns out the best wavelength is 532 nanometres - that's green visible light - with a pulse length of 4 nanoseconds, which is quite long. We have repeated the printing/unprinting process three times on the same piece of paper with good results. The more you do it, though, the more likely it is for the laser to damage the paper, perhaps yellowing it.Our ambition was to develop a method that would remove conventional toner from conventional paper in order to allow re-use of the paper. Toshiba's is a different approach to the same problem."

Cover image credit: Getty Images 

Published Date: Mar 16, 2012 03:57 pm | Updated Date: Mar 16, 2012 03:57 pm