Researchers at the University of Cambridge have discovered a way to use lasers to remove toner ink from paper so that it can be reused instead of being recycled or, worse, tossed in the garbage. In the future, those old TPS reports taking up space on your desk could quickly be turned into clean sheets of paper by sending them through an "un-printer."
The researchers studied 10 different laser setups ranging in strength and pulse duration and across the spectrum from ultraviolet to infrared. Using standard Canon copy paper printed with HP Laserjet black toner, the group exposed the paper to the lasers and then analyzed it with a scanning electron microscope. The group found that a variety of laser configurations could effectively remove toner ink without causing any significant paper damage, though damage did occur after the same sheet was processed several times.
So, when will we be able to get our hands on an un-printer? It may not be long. Dr. Julian M. Allwood, leader of the Low Carbon Materials Processing Group at the University of Cambridge said, “What we need to do now is find someone to build a prototype. Thanks to low-energy laser scanners and laser-jet printers, the feasibility for reusing paper in the office is there.”
Wide use of this technology could have a huge impact. Reusing paper could reduce emissions by 50 to 80 percent over paper recycling, which, while far better from an emissions and resource-use perspective than new paper production, still uses a lot of energy, water and chemicals to get the job done.
The researchers published the full results of their study in last month's Proceedings of the Royal Society A.