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.
We don't need no steenkin' shredder!
great, just think what the government can do to your personal infomation
contract? what contract?
"Hey Doogle, I found this "R" laying on the floor from previous post"
A buddy of mine was in a heavy metal band in the 80’s and in a drunken debauch got a massive tattoo on his shoulder. It was awful. Unbelievably bad in design, the lines were blurred, color was garbage. I’ve seen prison tats that looked better than this.
He just finished his last laser removal session — they burn the ink out of your skin. It vaporizes and he said it felt like his skin was on fire at the end of each session. But the tat is gone now with only a faint ghost. So to answer your question, it’s already been done.
Try that on the NY Times.
I do not think it would work on newsprint. But I am not completely sure about that.
How about a flamethrower?
Enviro-Nazis plotting again. Who is paying for their "research"? Duplex printing will not be enough for them?
You can the abstract of the paper here:
Toner-print removal from paper by long and ultrashort pulsed lasers
David Ricardo Leal-Ayala1, J. M. Allwood1,*, M. Schmidt2 and I. Alexeev2
1Low Carbon Materials Processing Group, Department of Engineering, University of Cambridge, Trumpington Street, Cambridge CB2 1PZ, UK
2Lehrstuhl für Photonische Technologien, Paul-Gordan-Straße 3, 91052 Erlangen, Germany
So I can buy a “de-laser” machine ,, buy a cashiers check for $10 , de-laser it ,, and imprint my new amount ,, say $100,000.00 and change the recipient at the same time.. cool.
Actually the laser heats the ink particles and explodes them into smaller particles that your skin cannot retain , they get flushed out by your kidneys ..
But there is security devices in checks such as watermarks.
The man who designed those watermarks in checks is Frank Abagnale Jr. whose life was made into the movie “Catch Me If You Can”.
Except that carbon in the air is not really a significant problem. And the volume of carbon in paper used at today's (declining due to advances like e-book publishing) rate is such a microscopic fraction of the earth's natural carbon load that you could never measure the effect of your proposal.
And don't try to lay any "global warming" BS on us!
If you are truly commited to stopping "AGW" -- stop breathing!
That's nothing. Washington, DC politicians have been "unprinting" documents for decades.
Fortunately, some of us still retain copies...
When do we start?
If this process were done in economically significant volume, dealing with the vaporized polymer binder would be an issue (at least in the building where the process was performed).
Simply performing the ablation in a suitably oxygen-enriched environment would dispose of the polymer (and carbon pigment) -- and provide a smidgen of that good old carbon dioxide that green plants need to thrive.
And, as I said previously, don't give me any "AGW" BS. The feedback has been empirically shown to be negative. (The warmists' computer models -- which all use positive feedback -- are junk...)
You are welcome. It was necessary to lay everything out on the table for you to see.
Thanks Hegemony Cricket. I remember a show, Cronkite did it, called “The 21st Century” — one segment showed a typewriter (whatever that is) which used a laser to erase mistakes, a capability which was used “on the go”, since we didn’t have such cushy computer equipment and the like back then.
The laser used to be dubbed, “the solution in search of a problem”. Imagine. :’)
You just need to buy carbon offsets from Al Gore each time you vaporize polymers and heat up the earth and the negative effect is erased.
But there is security devices in checks such as watermarks.
That is why I said “buy a cashiers check” ,,, otherwise you can just print them up on any laser printer at home..
How to tell if a cashier’s check is counterfeit
Not nearly as cool as the vaporizing story he told me. Bummer.
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