A new way of “unprinting” paper, unlike laser-based methods, can work with the standard, coated paper in our home and office printers.
The new method uses pulses of light from a xenon lamp, and can erase black, blue, red, and green toners without damaging the paper, according to a study in the Journal of Cleaner Production. The method could curb environmental impacts compared with conventional paper recycling.
“Our method makes it possible to unprint and then reprint on the same paper at least five times, which is typically as many times paper can be reused with conventional recycling. By eliminating the steps involved in conventional recycling, our unprinting method could reduce energy costs, pollution, and greenhouse gas emissions,” says study coauthor Rajiv Malhotra, an assistant professor in the mechanical and aerospace engineering department in the School of Engineering at Rutgers University-New Brunswick.
Conventional recycling of coated paper is a major contributor to climate change emissions, chemical pollution, and energy use, according to the study. Extending the life of paper while avoiding these recycling steps would yield significant environmental benefits.
The engineers’ next steps are to further refine the method by testing additional toner colors on a wider range of paper types. Unprinting can be done with simple equipment and a wipe with a very small amount of benign alcohol, and the engineers are working to integrate unprinting with typical office and home printers.
Additional researchers from Rutgers and Oregon State University contributed to the work.
Source: Rutgers University