Xerox has invented an erasable printing technology that allows paper to be reused. The paper self-erases in 16 to 24 hours. 

Created in collaboration between the Xerox Research Centre of Canada (XRCC) and the Palo Alto Research Centre (PARC), the innovation is part of a laboratory project that focuses on the concept of future dynamic documents.
“Xerox estimates that up to two out of every five pages printed in the office are for daily use, having been printed for a single viewing,” says Rob Abraham, MD of Bytes Document Solutions.
“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 would all like to use less paper, but many people still prefer to work with information in the traditional format.
"Self-erasing documents for short-term use offer the best of both worlds and could some day replace printed pages that are used for just a brief time before being discarded, thus leading to a significant reduction in paper use.”
To develop erasable paper, Xerox researchers needed to identify ways to create temporary images. This was achieved by developing compounds that change colour when they absorb a certain wavelength of light and then gradually disappear.  
While scientists at XRCC continue to work on the chemistry of the technology, their counterparts at PARC are investigating ways to build a device that can print the image on to the special paper.
The completed prototype achieves this 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,” Abraham says.
“Temporary documents are part of Xerox’s ongoing investments in sustainable innovation or green products that deliver measurable benefits to the environment.
"Other such innovations include solid ink printing technology, which generates 90% less waste than comparable laser printers; more energy-efficient printers, copiers and multifunction devices; and other paper-saving innovations.”  
The Xerox Innovation Group conducts work in colour science, computing, digital imaging, work practices, electromechanical systems, novel materials, linguistics, work practice analysis and nanotechnology connected to Xerox’s expertise in printing and document management.