Re-writable paper

Despite the advent of computers, smartphones and tablets still quite often we use pen and paper. And when the paper has done its job, we throw it away. It ends at the old paper or at the dump. Actually sin, so find Chinese researchers. And so they come up with a solution. They developed a low-cost, environment-friendly way to make re-writable paper.

The paper is made of tungsten oxide and a polymer which is frequently used in food and medication. In order to "print" .the paper, the researchers found the paper exposed to ultraviolet light for 30 seconds. Then colored it blue paper. To put words and images on the paper, they put a template before exposing the paper to ultraviolet light. Then, only the ultraviolet light-exposed parts of the paper. The images disappear when they are exposed to oxygen or ozone.

To delete the words or images on the paper, you can just leave your paper a day or two. Do not you have much patience? If you expose the paper to heat, the blue color disappears within thirty minutes. Want to keep your message longer? That is a possibility. When the researchers added a specific polymer to the paper, the messages remained ten days on the paper before disappearing.

Experiments show that the paper can be rewritten as forty times. Only then the quality begins to go down, so the researchers write in the journal ACS Applied Materials & Interfaces.