Today, printers are an integral part of life without which the conduct of business and any turnover of documents becomes impossible. In addition, for the printing process use a lot of paper — which is not very good from the point of view of forest preservation, there is another problem — ink. The fact that modern ink for printer are produced with the use of zinc and other compounds that can harm the environment.
But probably this problem is already solved — the enterprising Chinese. Professor Sean Zhang invented an unusual way of saving natural resources — it is proposed to replace the ink with water. And documents look like a regular print, with text that is easy to read. What's the catch, you ask? It is hidden in a special paper. Has developed a special coating that activates the dye molecules, — it is manifested only in contact with water. To get the black color on the paper, it is covered with a special composition, using blue, Magenta gold and purple colors.
See also: a 3D printer back duck. paw
Another unusual finding Chinese — reusable paper. The printed characters on the paper during the day. And after just disappear, and paper can be reused.
Source: /users/413