Scientists suggest lasers can remove ink from paper

Dr Julian Allwood, leader of the Low Carbon Materials Processing Group at Cambridge University, tested toner-print removal from paper by employing a variety of lasers.

According to a statement, the results showed that toner ink can be removed effectively without causing significant paper damage.

Coupled with advances in hand-held scanning technology, wireless devices, shredders, copiers and printers, the research means that ink-removing devices may soon be a common sight in offices around the country.

Allwood said: ‘What we need to do now is find someone to build a prototype. Thanks to hand-held scanners and laser-jet printers, the feasibility for reusing paper in the office is there.’

The implications of the study also extend beyond the workplace and into the forest. Removing the tree from the paper lifecycle is a real possibility. Along with saving forests from being used for new paper, reusing paper saves an additional 20 per cent in emissions over recycling.

The study poses the question of what would happen if paper was unprinted and reused instead of recycled. The action of removing ink with a laser would remove four steps from the paper production cycle: forestry, pulping, paper making and disposal by incineration or landfill.

The study shows that avoiding these four steps would result in a 95 per cent reduction in emissions per tonne produced from the production of office paper, rather than the 76 per cent reduction we see now from recycling.

Allwood added: ‘Material recovery through reusing eliminates the forestry step from the life cycle of paper and eradicates emissions arising from incineration and landfill dumping.’

With the aid of The Bavarian Laser Centre, a total of 10 laser set-ups of various strength and duration were tested in the study. The lasers spanned the ultraviolet, visible and infrared spectrum. The paper used in the experiments was standard Canon copy paper with HP Laserjet black toner, common in offices around the world.

Once the paper was subjected to the laser, the samples were then analysed by a scanning electron microscope.

The study postulates that the emissions produced in the pulp and paper industry would be halved as a result of paper reuse.

‘This is a significant contribution towards the cause of reducing climate change emissions from paper manufacturing, but there is modest room for improvement,’ said Allwood.