Researchers at the University of Cambridge in the UK have developed a method for removing laser-printed text from paper. It could mean devices used for security, recycling or both.
A team lead by Dr Julian Allwood (pictured) explored practical applications that as lasers are used to attach ink to paper, they can also be used to remove it. They discovered that while a variety of wavelengths of light from ultraviolet to infrared worked, the most effective was a visible green light.
The technique worked by using the laser beam to apply the right level of heat for a mere four billionths of a second. It isn’t a case of the words dropping off the page: the heat vaporized the toner, with the resulting gas being captured in a filter. Allwood says the technique worked on a range of toners and does not damage the paper or leave it unable to “receive” toner in the future.
The new research follows a 2009 study by Allwood to see whether a variety of solvents could remove toner while leaving paper ready to be reused. That study concluded that it was technically possible but that it might only work on particular combinations of paper and toner type, that results could vary depending on ambient temperature, and that the most effective method would not be viable in office use because it involved chloroform.
According to the team, building a single prototype of a device using the laser technology would cost around £19,000 (approx US$30,000) but commercial production could reduce that to £16,000 ($25,000.) They believe that for larger companies, particularly those with busy offices, the devices could pay for themselves by cutting the amount of paper they needed to buy. It could also be an alternative to shredding or burning sensitive documents.
Management at Dunder Mifflin were unavailable for comment.
The work is detailed in Proceedings A, a publication of the Royal Society. That’s the same title that first published research including Crick and Watson’s description of DNA’s structure and Maxwell’s electromagnetic theory.
Allwood previously made the headlines when he came up with a creative way of visualizing the amount of resources the human population consumes each year. He expressed the consumption in terms of the number of people-sized statues you could sculpt from each material, calculating that the average UK citizen consumes 12 “coal adults”, four “paper adults” and even an “aluminum baby.”