Paper waste is one of the biggest environmental issues we’re facing nowadays. A team of researchers has come up with an interesting solution to this: rewritable paper.
They made the recyclable paper from tungsten oxide and a common polymer used in medicines and food. More scientific data can be found in the journal ACS Applied Materials and Interfaces.
The new recyclable paper can save water, energy, landfill space and could reduce greenhouse gas emissions associated with all of the above.
So, how does one actually use the paper?
The two materials they made the recyclable paper from are tungsten oxide and polyvinyl pyrrolidone. If exposed to ultraviolet light for at least 30 seconds, the materials color themselves into a deep blue. If you want to write words on it, you have to use a stencil, so that only the parts that are directly hit by ultraviolet light turn blue.
After a day or two in ambient conditions, or if you heat it up, the material erases itself. Longer-lasting versions can be made by adding a small amount of polyacrylonitrile to the material and the blue lasts for up to 10 days and can be rewritten for up to 40 times.
This reminds me of rewritable CDs and DVDs.
This invention clearly lacks the simplicity of classic pen and paper, and it may look like it’s nothing worth mentioning, since we already have tablets and e-paper displays and so on.
However, you have to keep in mind that this is only early research and that methods for writing and rewriting it can further be examined, so maybe one day you’ll write with an ultraviolet pen just like you would with a regular pen, and erase that paper in an instant by passing that pen above it, or even by electronic means.
In the old days, people would use pencils and erasers to recycle paper. Then, it was a matter of money – now it’s a matter of doing the right thing.