The image on this cell phone case can change because it was made with rewritable paper. Source: American Chemical Society

Paper is traditionally a one-use product. When a notebook is filled and outlives its usefulness, it gets discarded, which is quite wasteful. However, engineers from Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials and the College of Physics and Energy, Fujian Normal University have created a new, rewriteable paper that can be written or printed on repeatedly, while retaining inks for six months.

This is the longest-lasting rewriteable paper yet. Past rewriteable papers had challenges that limited their utility, as written messages were only kept for a few days or months. Rewriteable papers have also proven difficult to manufacture. Many have chemistries that rely on ultraviolet light to erase a message or need constant energy to maintain writings.

The team of engineers has created a rewritable paper that is easy to produce and can be wiped clean quickly. The new paper material is created from three sandwich-like layers. One side of the paper is painted with a blue dye that turns colorless when heat is applied. The other side of the paper is covered with a black toner layer that creates heat when it is exposed to light. A heat pen, thermal printer or infrared light source creates writings, drawings or printings on the paper. To reset or erase the paper it must be cooled to 14° F.

During testing, the team created images on the paper that could last up to six months. They also created a rewriteable cell phone case that lasted up to six months as well. The testing found that the paper could be erased and rewritten on up to 100 times.

The team hopes that one day this paper will be released to the public, but they don't know when it will be commercially available. The researchers need to put their rewriteable paper through more testing and developing before it can be mass produced.

The report on the rewritable paper was published in ACS Applied Materials and Interfaces.