Unprinting: New Device Removes Ink From Paper & Cuts Down Environmental Impact


A Rutgers-led team has developed a new device which can unprint paper, essentially removing ink and allowing the paper to be reused multiple times. Unlike other similar devices, the new unprinter can be used with the standard paper type used in home or office printers, making it significantly more important for the average consumer.

Unprinting technology has been around for a while now, with a University of Cambridge laser-based unprinter dating back to 2012. That technology, however, required high-powered picosecond lasers, a type of equipment that virtually excluded it from wide commercial use.

Cheap Equipment & Alcohol Wipes


The new unprinter is much simpler and cheaper, making it significantly more suitable for everyday use in modern homes. The technology uses a xenon lamp to generate pulses of light which are then used to erase black, blue, red and green toners – all without damaging the paper. The device requires only simple, easily accessible equipment and a wipe with a small quantity of benign alcohol.

Additionally, the unprinter can also be used on standard coated paper, the type of paper most widely used in everyday printing – and, through its extensive standard recycling process, a major contributor to climate change emissions.

Far Better Than Current Paper Recyling

With the new technology, a user can print and unprint the same sheet of paper multiple times, thus making it a far more effective recycling process that existing technologies.

Rajiv Malhotra, study coauthor and assistant professor in the Department of Mechanical and Aerospace Engineering in the School of Engineering at Rutgers University-New Brunswick, explains: “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.”

The next goal for the research team is to refine the method by testing new toner colors, extending it to more paper types, and integrating the unprinting system with mass-produced home and office printers.