Become a fan of Slashdot on Facebook

 



Forgot your password?
typodupeerror
×
Earth Science Technology

Scientists Have Invented Paper That You Can Print With Light, Erase With Heat, and Reuse 80 Times (qz.com) 159

An anonymous reader quotes a report from Quartz: Nearly 1% of carbon emissions annually can be attributed to paper production, even though we recycle much of the paper we produce. Yadong Yin has a solution. He and his colleagues at the University of California at Riverside have invented a type of paper that can be printed on using just light, erased by heating, and reused up to 80 times. Yin created nanoparticles, which are a million times smaller than the thickness of human hair, with the dye Prussian blue, or its chemical analogues, and titanium oxide, which is commonly used in white wall paint. This mixture is then applied to normal paper. When the coating is exposed to ultraviolet light, electrons from titanium oxide move to the dye in the nanoparticle. This addition of electrons makes the blue dye turn white. Focusing the ultraviolet light into shapes, you can print white words on a blue background -- or blue words on a white background, which are easier to read. If left alone, the paper reverts to its original state in five days. That process can be accelerated by heating the paper to 120 C (250 F) for 10 minutes.
This discussion has been archived. No new comments can be posted.

Scientists Have Invented Paper That You Can Print With Light, Erase With Heat, and Reuse 80 Times

Comments Filter:
  • New printer (Score:5, Funny)

    by religionofpeas ( 4511805 ) on Tuesday February 07, 2017 @05:13AM (#53817619)
    Now all we need is a new printer that doesn't jam when the paper is not perfectly smooth.
    • Re: (Score:2, Interesting)

      by Anonymous Coward

      Now all we need is a new printer that doesn't jam when the paper is not perfectly smooth.

      Well, no. Not quite.

      All we truly need to fix the problem of printer jams is a society that doesn't believe in going backwards with technology in order to feed some perverse addiction of putting ones and zeros on paper.

      While I applaud the new research for helping with carbon emissions, it's pretty sad when we've been talking about "paperless" for 20 fucking years and have still failed to actually do it in damn near every aspect.

      And yes, it's pretty easy to do. When gas rose to over $4/gallon, people starte

      • by Dog-Cow ( 21281 )

        Going paperless is extremely expensive. Paper would have to cost more than gold for the same weight.

        • How literally do you mean "paperless"? Matte mylar may be as low as 6 cents for a letter-size sheet for thin stuff of questionable quality; sturdy stuff for engineering drawing about 50 cents.
          • and a sheet of printer paper costs 1.3 cents, and thats for a single ream, you buy in cases, it goes down to half a cent per sheet, and it probably dips lower if you buy by the pallet, which I'm sure many large companies do.
      • Re:New printer (Score:5, Informative)

        by AmiMoJo ( 196126 ) on Tuesday February 07, 2017 @06:29AM (#53817807) Homepage Journal

        Paper has some useful properties that help it remain popular. If we can replicate or better these properties with technology, we can finally go paperless.

        Cheap, disposable: Compared to a tablet computer, paper is very cheap and damage is rarely a big deal.

        Just works: No battery to charge, folds up if required, can be marked with any pen or pencil and there is no UI to learn or fumble with.

        Permanent: People trust printed documents not to change and signatures/stamps count for something.

        Archival: Paper lasts a long time, and people know how to protect it. Digital files get lost, formats go obsolete and unreadable, same for the storage media. Backup still seems to be hard compared to "file in fire-proof safe".

        Size: Even just A4/letter size tablets are expensive, let alone A3. Larger sizes can't be folded either.

        Compatibility: Different tablets have different ways of distributing and accessing documents.

        There are a few areas where paperless wins. Machine translation is getting very good. But it's still a struggle. Where I work we are replacing paper drawings with Raspberry Pi and monitors, basically glorified PDF readers. It only works because our CAD documents are exported to PDF for easy viewing and stored on a file server somewhere, but it's far from a turnkey, universal solution.

        • Re: (Score:2, Interesting)

          by Anonymous Coward

          Only your durability / hardcopy / archive argument really hold water and that's exactly what this ‘invention’ is useless at.
          * Paper is expensive. You don't realise that because you aren't paying the price in the store. But it takes up space, ordering time and other overhead and it turns out to be much more expensive than any digital-based solution (be it e-reader, computer, ...).
          * My e-reader also ‘just works’ (battery lasts forever, can write on pages) and people can no longer live

          • Have you ever needed to compare a moderate number of documents, say 8 documents of 5 pages each? Spread them out on your desk, shuffle them, move them around, make notes and editing marks on them. How are you going to do that with e-readers? Now tape a few of them together to form a 17 by 22 inch document with all the details visible at once.

            I hope you have a solvent for the duck tape residue from taping together the e-readers, a solvent that doesn't attack e-reader case plastic.

          • by Khyber ( 864651 )

            " My e-reader also ‘just works’"

            Until you break your screen.

            You got any non-paper archives that have lasted several thousand years, or even a couple hundred?

            That's what I thought.

            You can't hack paper, either. Thus it's a far more secure medium for information storage.

            • Well this "new paper" won't last several thousand years either. The ink disappears within 5 days- or quicker if you heat it. The very act of holding the paper, or even breathing on it will erase the ink.

              In other news, I'm getting a check book made out of this paper...

              " I don't see a signature".

        • by Bengie ( 1121981 )
          As useful as paper can be, there are many situations where someone will print off 100+ pages just to throw them all in the bin a few hours later. The real question is how often does this happen will answer what the max savings of that maximum 1%.
          • And in many cases the 100+ pages thrown in the bin weren't intended to be, there was just something wrong about it. The original intent was a permanent copy. So it's hard to predict ahead of time when "reusable paper" would be beneficial over normal paper.

        • No battery to charge, folds up if required, can be marked with any pen or pencil and there is no UI to learn or fumble with.

          I had to learn the UI. What, were you born knowing how to read and write?

        • For one, the IRS. They love their paper for all but simple tax filing. I recently had a minor issue and they would accept FAX, or paper snail mail corrections. FAX? who does FAX anymore. Paper meant I had to print out a new copy of the corrected form from pdf and then mail it. Two pieces of paper.

        • I recall decades ago Xerox tried marketing an erasable paper copy machine. Never heard of it? Right. It wasn't popular.

        • Paper has some useful properties that help it remain popular. If we can replicate or better these properties with technology, we can finally go paperless.

          Something like this was already invented about a decade ago and posted on slashdot. I'll repeat the info from what I thought was the most insightful post from that discussion:

          We shouldn't be trying to replace paper. We shouldn't even be recycling it. We should be using as much of it as we can and throwing it all away in the trash.

          • Why do we have a
          • by Altrag ( 195300 )

            This is so absurdly wrong its almost funny. That carbon you're talking about is already "sequestered" in the trees you're cutting down -- its not in the atmosphere!

            And the tree you just cut down is now no longer pulling any more carbon out of the atmosphere.

            Never mind things like the equipment needed to cut down, transport, mash and reconsistute the wood into paper all requires fuel, the majority of which is going to be carbon-based, so there's a big subtraction from your equation (that may even go negativ

        • Not sure what your comment has to do with the article, other than that it points out that this new paper has few or none of the properties that make paper desirable.
        • My google-fu is a bit weak right now for some reason, but a general once said that a computer with a bullet hole in it is useless but a paper map with a bullet hole in it is still useful.

      • Does that mean I shouldn't be printing raw binary dumps of my PDFs?
    • This was my first thought.
      I've seen it, in a non-profit environment : using some decade old HP laser printer, with seemingly perfect reliability (compared to your typical inkjet that you need to re-buy every year if you use it seasonally), enough life left in the toner to not care about it.

      Yet, the obvious "good idea" there was to print on old worthless already printed paper, just print to the other side. It's not so much the paper jams that are a problem, but all the dust, dirt and ash particles found on t

      • My hplj2300 (best b&w printer evar) has problems picking up paper when it's not fresh. After it's been cooked, it seems to provide less traction.

    • Or user-replaceable rollers on inkjets, since the real problem is hardening of the rubber.

  • by Required Snark ( 1702878 ) on Tuesday February 07, 2017 @05:19AM (#53817633)
    They can use this for all internal and external communications and never have to admit that they lied or changed their position.
  • by Rande ( 255599 ) on Tuesday February 07, 2017 @05:20AM (#53817641) Homepage

    See? This is your employment contract with your signature at the bottom, and it says right here in clause 13a that we're allowed to ride you like a donkey every 2nd Tuesday.

  • I think this is great for scratch pads but unless there's also a way to make the print last longer the applications would be limited. "If left alone, the paper reverts to its original state in five days. That process can be accelerated by heating the paper to 120 C (250 F) for 10 minutes." Slowest Etch-a-Sketch ever?
    • "If left alone, the paper reverts to its original state in five days"

      This is the thing that would keep me from buying it...oftentimes I don't know if I'll need to keep something I print out for a day or a week or a month.

      I'd hate to print something off only to find out that it had self-erased a week later.

      • by guruevi ( 827432 )

        Some people (*cough* Wall Street types *cough*) just want to make sure that whatever they printed out, e-mailed etc gets destroyed after a few days/weeks/months. They often don't use e-mail because they lose control and rely on word of mouth and paper within the office to get their 'ideas' finalized. The main issue is when the shit hits the fans months or years down the line, they don't want anyone holding onto anything they've said or written.

        With this paper, any evidence disappears automatically and you'd

  • The one thing I print things for is to be able to annotate by hand. That will not work with this paper, obviously, or require special markers. I also need these notes typically significantly longer than 5 days.

    The only way to deal with this is to recycle paper. Where I live it is solved very simply: Normal trash you pay for by volume actually produced (you need to use special bags). Paper, cardboard, metal and glass you can either throw in the normal trash and pay for it or collect it separately and dispose

    • by hagnat ( 752654 )

      being useless to you doesn't mean its useless for others.

      Imagine this being used in convention centers, where one could print the daily schedule on a sheet of paper that was reused from a previous convention.
      This used in mass to handle today's sermon and lyrics to the churchgoers, and then have the flyer be reused on the next day for a different sermon.
      This used internally in companies to share confidential information among employees.
      This used in hospitals, to print the information of a short-term patient.

      • Re:Sounds useless (Score:5, Interesting)

        by omnichad ( 1198475 ) on Tuesday February 07, 2017 @08:51AM (#53818297) Homepage

        It can be reused/reprinted 80 times. It doesn't say it will stay wrinkle/crease free for 80 reuses. And when it does get thrown out, it's full of ferric ferrocyanide, which is fairly toxic.

        Any amount of wear on the paper and nobody will want it second-hand. Or, nobody will buy their own paper because it's too expensive. They just won't return the paper back to the convention staff, etc.

        • by Khyber ( 864651 )

          "And when it does get thrown out, it's full of ferric ferrocyanide, which is fairly toxic."

          Ferric Ferrocyanide is bound to iron and won't bind to your blood cells due to that. It's safe and that is why it was included in pretty much every children's chemistry set to this very day. It's also an FDA-approved food additive/colorant. The only real use restriction it has is that it is not intended for cosmetics which get applied to the lips.

          Sources: Environment Canada, NLM, FDA, European Commission.

          • Weird that the MSDS for prussian blue [sciencelab.com] is still pretty scary.

            Alright - we'll stick with the titanium dioxide, then, which despite getting sprayed all over people's bodies in summer is still a known carcinogen. Oddly enough, it rates lower on the MSDS health risk scale [sciencelab.com] than prussian blue.

            • Well, the MSDS for "Sea sand, washed" is pretty scary, too. Prussian Blue is amazingly non-toxic for something with "cyanide" in the name, and is used as a chelating agent to treat heavy metal poisoning.
              • I had no idea that breathing in sand dust could be carcinogenic. That is legitimately scary.

                To be fair, most things you can ingest are better for you than heavy metal poisoning. Wasn't worried about the cyanide in the name, per se, but that non-food/medical grade prussian blue may have some dangerous contaminants created during its production.

    • That will not work with this paper, obviously, or require special markers

      It would require a UV light pen.

      If you need it longer than 5 days, scanning or photo might be an option.

      However, this would probably be the only use case where the paper could likely be re-used more than once or twice.

      • If it reverts in 5 days, it's probably badly faded in one day. Better scan it soon, and print it out on (gasp!) paper.
        • GP only printed it so they could do handwritten notes. Presumably they would be happy with a digital copy.

  • So he invented Dito paper without the smell ? what's the use ?

  • Useful (Score:3, Insightful)

    by Dunbal ( 464142 ) * on Tuesday February 07, 2017 @05:54AM (#53817731)

    That process can be accelerated by heating the paper to 120 C (250 F) for 10 minutes.

    Or, just forget your documents in the car in summer one day and have them all erased.

    • by AmiMoJo ( 196126 )

      If the inside of your car hits 120C you have other problems, like the dashboard starting to melt. For example, ABS melts at 105C.

      • Many chemical reactions double in rate for every 10 Celsius degrees. (120 hours / 0.16 hours) = 750. 2^((120 degrees - 23 degrees)/10) = 831. That's pretty close agreement for a publicity blurb. "A summer day in your car" (10 hours) corresponds to 59 degrees Celsius, if I did my calculation right. That's 138 degrees Fahrenheit. Easily achieved.
    • Sounds like the plot to a new book, "Fahrenheit 251".
  • It uses regular paper as its base and then is coated with their nanoparticle brew, and it's supposed to be a resource saver?

    Maybe in a closed loop environment where there is a ton of printing for short-term purposes where the week-long lifetime doesn't matter AND you can re-use the paper close to the maximum number. But what do you bet in real life it would get printed on once and then the paper rendered impossible to print on due to wrinkling, tears, etc.

    Although at so many offices there's a printer and t

    • by davidwr ( 791652 )

      Maybe in a closed loop environment where there is a ton of printing for short-term purposes where the week-long lifetime doesn't matter AND you can re-use the paper close to the maximum number

      Yes, this. Someone mentioned convention centers and church bulletins as possible applications.

      However, even these are limited as many of these documents are typically multiple-color at least on part of the page and/or they are being replaced with apps, screens all over the place, or other paper-less versions.

      • Yes, this. Someone mentioned convention centers and church bulletins as possible applications.

        However, even these are limited as many of these documents are typically multiple-color at least on part of the page and/or they are being replaced with apps, screens all over the place, or other paper-less versions.

        What percentage would be successfully collected, and would they be in good enough shape to be reused?

    • Although at so many offices there's a printer and then there's the inbox-type container with ream-and-a-half stack of printouts that nobody collects from the printer and that just sit there until the inbox overflows and somebody dumps the entire stack into the recycling bin.

      Perhaps if the printer could do an erase stage at the start of a print job you could have a printer that automatically recycles the output bin after 30 minutes back to the tray so it could be erased again.

      My workplace has been installing Multi-function copiers where print jobs have to be locked, and the user has to go to the printer, select their job(s) in the queue, and enter their password (usually 0000, 1234, or their phone extension) before it will print. Jobs automatically delete after 2-3 days. It drastically reduces the number of abandoned printouts.

      Unfortunately these $10,000+ printers seem to be real pieces of shit, jamming constantly in very complicated manners, and requiring repairs all the time (

      • by swb ( 14022 )

        Unfortunately these $10,000+ printers seem to be real pieces of shit,

        Oh, they're awful. Shitty software, terrible interfaces and half the time at customer locations the important bits that show you networking configuration are needlessly locked out by the vendor.

        And quite often finding the right driver (and knowing what the right setting is) requires the knowledge of 1-2 people at the "copier" company, which is staffed mostly by sales and mechanical technicians.

        When I last went through this exercise as a full time admin, I got a full court press from the office manager (who

        • Oh, they're awful. Shitty software, terrible interfaces and half the time at customer locations the important bits that show you networking configuration are needlessly locked out by the vendor.

          And narcoleptic. They fall asleep after 10 seconds idle, and you have to press the stupid leaf button to wake it up, which takes 45 seconds to reinitialize, and the scanner buffer was limited to about 2 pages. I was able to corner the service tech once to get those limitations lifted (it sleeps now after 60 minutes, and can scan dozens of pages).

          Occasionally the MFP would lock up. You send a job, select it, enter your code, and it would go "processing" indefinitely. Once I said "fucking piece of shit", pull

  • So you reduce the demand for new paper you cut down on the trees planted.

  • Can they also prove particles are harmless for the environment ? Where does the heat come from ? And how much energy does it take to apply the stuff ? What's the chance of mixing it up with normal paper and throwing it away too soon ?

    • Re: (Score:3, Informative)

      by arboviral ( 4862243 )
      It's likely to be pretty safe. The process uses Prussian blue (iron hexacyanoferrate) and titanium oxide (presumably titanium (IV) oxide, given the reference to white paint). Prussian blue is non-toxic and highly stable, despite containing cyanide groups (https://en.wikipedia.org/wiki/Prussian_blue#Adverse_effects) and is actually used as a treatment for heavy metal poisoning. Titanium (IV) oxide is so safe it's often used as a food additive, as well as already being a component of many papers - it helps ma
      • by Anonymous Coward

        The only reason Titanium oxide has not been banned yet is strong lobbying by the food industry.

        It is well known to be a highly reactive substance (used in drugs to increase their penetration in cells). Sprinkling it right and left in direct contact with human beings, and hope they are not simultaneously exposed to something that will react with it, is sheer madness.

        But then, profit first, class actions second.

        • Titanium dioxide and zinc oxide are the 2 most common white pigments. It might be appropriate to ban it in foods (I'm ignorant here) but ban it generally, no way.
    • by Anonymous Coward

      "nanoparticles, which are a million times smaller than the thickness of human hair"

      HELL NO!!!
      When stuff like this gets in the environment and starts clogging up capillaries in the eyes and kidneys the people that created it should be punished publicly. Blindness and a lifetime of dialysis just because of some self aggrandizing scientists. Children doomed to a life of darkness and pain.

  • https://en.wikipedia.org/wiki/Blueprint

  • mimeograph? Wow, the future is a blast from the past. As in grade school.

    And now y'all have an idea of how old I am.

    • by dbIII ( 701233 )
      Grade school? Urk, the university I went to was still using those.
      A girl in my class got some purple from it on her new white blouse from the thing and one of the chemistry lecturers helpfully poured some acetone on it to clean up - he seemed sure he could pour on just a drop instead of spilling a lot on her, but he spilled it. Not just a white blouse a white NYLON blouse. In seconds she was half naked and sticky from dissolved nylon (like wearing cobwebs by that point) in front of an almost all male cla
      • They gave him a hard time for demonstrating the effects of acetone on synthetic fibers? Well, joke's on them, because his students will never forget his lesson that day.
    • mimeograph technology works by forcing a replenishable supply of ink through the stencil master. (wikipedia)

      No relation.

  • by ITRambo ( 1467509 ) on Tuesday February 07, 2017 @07:56AM (#53818061)
    Paper is cheap. It can be recycled. Trees are renewable. I don't see the need for this new paper, other than possible use in a Mission Impossible movie.
  • Paper is permanent (Score:2, Insightful)

    by Anonymous Coward

    The point of paper is that it's semi-permanent. That's why it's used so much. This does absolutely nothing to reduce the need for traditional paper. You could do the same thing with a decent tablet already, and for most things you just don't.

    • by PPH ( 736903 )

      This could be the re-birth of the pampliset [wikipedia.org]. Where some useful scientific work can be erased and the paper reused for religious nonsense.

      Personally, I welcome our new dark age overlords.

  • How will this affect my paperless office?

  • Does it smell like duplicator fluid or diazo?
  • ...in keeping a piece of paper at 120 degrees for ten minutes.

  • Have your congress critters write any stupid laws like DMCA on this, any damage gets undone after a few days.

  • Unless this paper costs less than 80 times the cost of a sheet of regular paper, it's a dumb idea. Not to mention the energy used in heating every sheet of paper you use to 120C instead of just recycling it.

  • ... used the same technology to detect goblins.
  • Cyanotype printing was invented in 1842

    https://en.wikipedia.org/wiki/... [wikipedia.org]
  • We've had disappearing ink for centuries. What good is this?

  • I don't want to see any "innovative" paper products until my grocery receipt is dollar-sized and printed on paper with out Bisphenol or some other such toxic nonsense on it. How many times have you bought just a couple things, and they hand you your receipt with the cash and the receipt is 3 times longer than a dollar and a lot wider too? What's up with that?

  • Any word yet as to how easily it will be for these nanoparticles to rub off and get into people's lungs?

    Very small particle pollution is a major source of lung cancer. As is often the case with most of new technology, there is little thought as to the long term health and environmental consequences of production and use. Such issues tend to be ignored in the rush to make money, but can end up costing everyone more than anyone expected, in many cases their very lives.

  • Many years ago someone came up with the idea of a DVD with a time-degrading dye. Rent a movie printed on one of these, and as soon as the renter opens the package the dye starts to oxidize and fade. No need to return it, it just stops working. See how popular that was?

    So, here's the perfect solution for libraries. Print-on-demand the book, assume it dies in five days, and then it is free to loan to the next person. You don't need a building full of dead trees, just reams of this paper and the special print

  • Been in the copier/printer business for over 35 years. Every major brand, has tried the "erasable" trick before, with terrible results. Mainly, the powder toner, reacts differently under a specific temperature. At one temperature, you can read the print. At another temperature, it turns the toner crystals/powder "clear". You can reuse the same paper about 3-5 times, before there is so much toner "clear" on the paper, that it leaves blank spots in areas where the toner is suppose to be, but can't adhere

"An idealist is one who, on noticing that a rose smells better than a cabbage, concludes that it will also make better soup." - H.L. Mencken

Working...