A method was created to unprint paper that, unlike laser-based methods, can work with the standard, coated paper used in home and office printers. The new method uses intense pulses of light from a xenon lamp and can erase black, blue, red, and green toners without damaging the paper.
The 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, the unprinting method could reduce energy costs, pollution, and greenhouse gas emissions.
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 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. Researchers are working to integrate unprinting with typical office and home printers.