Xerox Reusable Paper

Remember the magic slate? It’s a piece of board which can be written on by applying pressure. The contents can be erased my moving a slider between the two walls of the slate. A similar erasable paper is being developed by Xerox and the contents can be deleted as needed. It prints using a printer that uses no inks; instead uses light.

The reusable paper is printed on and erased, by exposing to light having a certain wavelength. It needs to be printed using a special printer with UV light source. The printed material doesn’t fade, smudge nor smear when touched. Researchers have so far cycled the paper by printing and erasing on it for around 50 times. On the downside, prints degrade after a few hours and eventually return to its blank form.

Here’s the technology behind this paper: The paper developed by Xerox apparently includes photochromic compounds (such as spiropyran) which exhibit heliochromic properties. That is, they darken when exposed to U.V. radiation and fade in the absence of U.V. light. Photochromic compounds are used in the manufacturing of certain sunglasses due to their ability to darken and regain their transparency quickly. However, a distinct difference from sunglasses is that Xerox’s erasable paper can remain darkened for many hours. The U.V. light source, called a light bar, is integrated into a printer which illuminates specific parts of the erasable paper, creating the desired text or image on the paper. The printer can also erase the paper using a different wavelength—making the paper reusable.

The reusable paper still has a long way to go. The paper currently prints in black as the targetted usage is for draft copies. The printing resolution is at a low 150 dpi. Other things that would influence the enhancement of this technology would be the cost factors incurred. Unless and until the price of the printer and paper stays close to inkjets, it would be quite impossible for it to make an impact.

via TFOT