You know, it is an era in which deforestation causes the loss of biodiversity, interrupts the water cycle and changes precipitation. The search for alternatives to recycle or produce paper it is more essential than ever. At least as long as paper printing is still so widespread (and someone would never deprive himself of it).
Scientists of the Nanyang Technological University of Singapore have developed a sunflower pollen-based paper that can be erased and reused multiple times without damaging the material.
How does the process of obtaining sunflower pollen paper work?
The production of this special printing paper is quite similar to that of soap. The cellular components encapsulated in the sunflower pollen grains were removed with potassium hydroxide, and later transformed into soft microgel particles.
To remove any undesirable particles from the pollen microgel, the researchers used deionized water. The microgel was then poured into a flat mold and air-dried into a sheet about 0,03 mm thick (that's about half the thickness of human hair). Last step: the sheet was coated with acetic acid to make it resistant to moisture.
Result? A paper that represents a very valid ecological alternative to the traditional wood pulp-based paper, more flexible and translucent, which is printed and erased.
The print tests (and reprint)
In testing, the team has established how high resolution color images could be printed on pollen paper (hypoallergenic, I want to say) with a laser printer and then "de-printed" by completely removing the toner without damaging the paper: an alkaline solution is enough.
At the end of the “de-printing” process, the now clean paper is placed in ethanol for five minutes. Another drying, new treatment with acetic acid and off we go, ready for a new print. The process can be repeated at least 8 times without loss of paper integrity or print quality.
The advantages over the past
I won't deny it: as a layman, reading about all these passages made me turn up my nose: in reality, the systems for recovering printing paper today require very strong solvents, or the use of intense light which ends up damaging the paper. This new method can help reduce CO2 emissions and energy consumption related to the conventional paper recycling process (which involves pulping, detonation and retreading).
Not to mention the fewest number of felled trees.
