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Please think about the environment before you print this article.

That sort of sentiment is often appended to e-mail signatures these days, underlining the ethical conundrum faced in an office environment every time we consider hitting the “Print” button. Many bemoan the printing of documents just for one time use when reading them off a digital screen can suffice.

Even though paper can be recycled, not all office buildings offer that service and tens of millions of tons of paper waste end up in landfills every year in North America. Plus, recycling that paper still takes energy, and there’s all the ink cartridges to dispose of. Given the environmental costs of printing and the renewed green movement, it’s no wonder many offices have made the effort to go paperless.

Nature had the researchers print a document in black and white and colour using its water-based paper and a HP DeskJet 2010 printer.

But sometimes you just want to read something off a sheet of paper.

A team of Chinese researchers may have come up with a way for you to do that without feeling any residual guilt. As documented in the scientific journal Nature Communication‘s January issue, Jilin University has developed a special type of reusable printer paper. Better yet, the paper allows you to reload your printer’s cartridges with water instead of ink.

Here’s how it works: a special type of “magic paper” appears blank when dry but changes colour when its moist. So the water-jet heads of the printer apply a bit of water and that triggers the dye in the paper and open up the molecules to appear as ink on a normal sheet of paper. But when the paper drys up, it goes back to being a blank page.

In tests, the team of researches were able to reuse one sheet of the paper 50 times. They used both a standard desktop printer with its cartridges filled with water, and a pen filled with water for hand writing.

Aside from the environmental benefits of such a technology, there’s also cost savings and security benefits to consider. An office could save on buying ink and paper supplies. Plus, there’d be no need to shred sensitive documents because they would simply return to being blank pages after enough time has passed.