Erasable paper could be key to saving trees

Stan Beer
Thursday, 07 December 2006 14:12

Your IT - Home IT

Xerox Corporation scientists have invented a way to make prints whose images last only a day, so that the paper can be continually re-used.  The technology, which is still in a preliminary state, blurs the line between paper documents and digital displays and could ultimately lead to a significant reduction in paper use.

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. 

Andy Lambert, managing director of Fuji Xerox Australia said, “Despite the ever-growing popularity of the internet and electronic-based communication, the printed page – and the use and purchase of printers – show no sign of disappearing. The Fuji Xerox Group has long-standing initiatives that enable reuse and recycling of our products. We want to offer future generations a fair go - so the environment and access to resources and opportunity that they inherit is no less than that enjoyed by this generation."

“Despite our reliance on computers to share and process information, there is still a strong dependence on the printed page for reading and absorbing content.  Of course, we’d all like to use less paper, but we know from talking with customers that many people still prefer to work with information on paper.  Self-erasing documents for short-term use offers the best of both worlds,” said Paul Smith, manager of XRCC’s new materials design and synthesis lab.

Xerox has filed for patents on the technology, which it calls “erasable paper.”  It is currently part of a laboratory project that focuses on the concept of future dynamic documents.

To develop erasable paper, researchers needed to identify ways to create temporary images.  The break-through came from developing compounds that change colour 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.  

While scientists at XRCC work on the chemistry of the technology, their counterparts at PARC – the birthplace of the laser printer – are investigating ways to build a device that could write the image onto the special paper.  PARC researchers developed a prototype “printer” that creates the image on the paper using a light bar that provides a specific wavelength of light as a writing source.  The written image fades naturally over time or can be immediately erased by exposing it to heat. 

While potential users have shown interest in transient documents, there is still much to be done if the technology is to be commercialised.  “This will remain a research project for some time,” said Eric Shrader, PARC area manager, industrial inkjet systems.  ”Our experiments prove that it can be done, and that is the first step, but not the only one, to developing a system that is commercially viable.”