Ink free paper to replace normal paper

A technological innovation could help address increasing problems in environment and resource sustainability. Paper, developed at the University of California, Riverside, can be written on and erased multiple times.

This paper, in the form of glass or plastic film, utilizes redox dyes. The dye makes the “imaging layer” of the paper, the images and text, and UV light photobleaches the dye except for the dye that makes the text or images on the paper. The UV light reduces the dye to its colourless state so that what can only be seen are the images or text produced. Anything written remains up to 3 days.

Everything is erased by heating at 115 C, whereby “re-oxidation of the reduced dye recovers the original colour.” Erasing can be completed in under 10 minutes.

With this method, this paper can be written on, erased, and then rewritten on more than 20 times “with no significant loss in contrast or resolution.” The paper can come in three colours: blue, red, and green.

According to Yadong Yin, a professor of chemistry who helped lead the research of this development, “this rewritable paper does not require additional inks for printing, making it both economically and environmentally viable. It represents an attractive to regular paper in meeting the increasing global needs for sustainability and environmental conservation.” This innovation could substantially reduce the use of paper, one of the promises of the new digital age.

According to the WWF, paper is being produced at around 400 million tons (362 million tonnes) a year and rising.