The technology, dubbed Erasable Paper, creates prints that only last for a day, then fades away. So the paper can be used over and over. They first started from the observation that there is still a strong dependence on the printed page for reading and absorbing content, so many e-mails and documents are printed out for brief viewing, then sent to the dustbin. Xeros estimate that 40% of pages printed in an office are for one-day use, so self erasing documents for short-term use was THE solution. The paper is special; when lighted with a special wavelength of light, it changes color then gradually will come back at its initial status in a 16- to 24-hour range. The paper then can be reused. Today, the printer is just a prototype and will remain a research project for some time, until a cost-effective system is developed.