Skip to comments.Lasers can 'unprint' documents
Posted on 03/17/2012 3:48:22 PM PDT by U-238
British researchers say they've developed a laser process that can "uncopy" toner ink from paper as an alternative to traditional recycling.
Scientists at the University of Cambridge say the process involves short laser pulses to erase words and images by heating the printed material to the point that it vaporizes.
The technique works with commonly used papers and toner inks and is more eco-friendly than recycling, they said.
"When you fire the laser, it hits the thin toner layer and heats it up until the point that you vaporize it," researcher David Leal-Ayala told the BBC.
"Toner is mostly composed of carbon and a plastic polymer. It's the polymer in the toner that is vaporized."
Tests carried out on the resulting "unprinted" paper suggested it had not sustained significant damage and was "comparable to blank unlasered paper," the researchers said.
Reusing rather than recycling paper would be good for the environment, they said.
"When you recycle paper you use a lot of resources," Leal-Ayala said.
"You use electricity, water and chemicals, and to be honest when you print something the only reason that you don't re-use the paper is because there is print on it.
"The paper is still in good condition and there is no point in going through all the heavy industrial process if the paper is still perfectly fine."
(Excerpt) Read more at spacedaily.com ...
yah just try to feed used paper into your printer. not practical!
This is good technology. Once you have bought paper and taken it to work or home and printed on it, it is a very resource intensive effort to re-collect it, take it back to a paper manufacturer in order to recycle it. I don’t think the process is cost effective, its just one of those things that makes us feel good. Having a small machine that recycles the paper right at the distributed source would save a lot of energy.
Somehow I’m wondering if vaporizing polymers is ‘greener’ than just throwing the stuff in the trash?
What about coffee stains. Will it undo coffee stains?
Hi-tech palimpsest ping
“What about coffee stains. Will it undo coffee stains?”
And if so, will the same process take them out of clothing?
Obama and his forgers might be very interested in this process!
Wait til the birthers find out about this!
In old times parchments (stretched sheep, calf, or goat skins) were regularly recycled by scraping off the ink of earlier writings for reuse. Same basic concept and, except that the vaporized ink is probably not the best stuff to breathe in, pretty cool.
Oh goody. Once we find a way to do this with toilet paper, Sheryl Crowe can go back to using more than one square!
The very definition of a "palimpsest" is a page which has been reused. Most calligraphers and illuminators used gum sandarac or some other type of pumice, but Emperor Nero, who was a calligrapher in his own right, was reported to use the chopped out tongues of slaves.
I had to present a certified, raised seal and signed BC to the Texas Public Safety Officers to get a drivers lic. last week! Went home pulled it out of a briefcase and was back with in an hour. Seems Berry can’t or wont do that!
Why stop at clothes. What about tattoos?
It’s a good thing that lasers do not use energy
What percentage of office paper people throw in a recycling bin are reusable this way? They get stapled, folded, and mutilated. They get damp, wrinkled, stained, written on with pens and markers. They get handled with sweaty oily hands, stuffed in books and briefcases, taped, and then end up wrinkled from being in the bin. I like to fold papers three time and stuff them in a shirt pocket. Would that be a crime?
Everyone would have to treat each piece like a valuable work of art and make sure to stack it neatly when its unprinting time comes.
All of this stuff sounds great “on paper” but its implementation is a different story. You’re still going to have to grind most of it up and make new paper out of ole.
problem is. The fake BC wasn’t printed so there’s nothing to unprint lazerly.
I’d bet zero wished this lazer thing was around 36 moons ago. He could have altered the BC he found in a book... then again toner wasn’t around back then.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.