Imagine a simple printer at your office or home that uses water instead of ink to print reams of papers. Possible, say Chinese researchers. But the catch is not in the printer but the paper.

 

 According to scientists at Jilin University in Changchun, China, the printed characters last for a day on a special paper that can then be re-used.“Every time you print, it's fresh,” Sean Zhang, professor of chemistry, was quoted as saying.

 

 “We are using a commercially available inkjet printer. We just filled the cartridges with water and put it back. It’s like normal printing. The magic is in the paper,” Zhang, a former researcher at Hewlett-Packard Labs in Menlo Park, California, told DiscoveryNews.

 

 This method allows the paper to be reused several times and could potentially have cheaper running costs.

 How did they produce this special paper?

 The team developed a special coating on the paper that responds to the water. 

 

 They were able to print various Chinese and English characters using blue, magenta gold and purple colours, using water as a key that activates the dye molecule. 

 

 "The next step is to combine colours to go black,” Zhang added.

 

 According to Kira Barton, professor of mechanical engineering at the University of Michigan, “going toward more sustainable techniques of printing is helpful and beneficial”.