Paper Doesn’t Have to be Disposable (Part 1)
Guest Post by: Carl Yee, founder of Blue Planet Ink
The paper used for printing and copying is usually considered to be single-use. Perhaps the back side can be used if it is blank, or some of the paper fiber can be recovered through recycling, but it can’t be used for printing again. Or can it?
Ideally, we could wave a magic wand to erase the printing so the paper would be just like new. No more waste and pollution from making and recycling office paper. Reusing 12 sheets of paper saves as much in carbon emissions as is emitted by a car driving one mile.
We don’t have that magic wand to turn printed paper back into blank paper, but the good news is that innovators have created technologies which get us closer to that ideal! Here I will share a few of them. There are many more, such as my own which I will share later in Part 2 of this series.
Erasable Toner Laser Printer (Toshiba)
Toshiba makes special laser printers that use an erasable toner. One example is the e-STUDIO 4508LP. The erasable toner is blue rather than black so documents are blue and white. Here is what they look like from a Toshiba video:
The printing is erased by heat. When heated the toner becomes colorless. The toner is still on the paper but invisible so the paper is blank and can be used again. If you write on the paper using a heat erasable pen such as the Frixion pens from Pilot, that too is erased by the heat that erases the toner.
The e-STUDIO 4508LP allows you to print with the erasable blue toner or regular black toner. It also functions as the erasing machine. To erase the paper you can feed a stack of paper printed with erasable blue toner back into the machine and the machine heats and erases each sheet. Toshiba also sells a stand-alone erasing machine called the e-Studio RD301 which scans each page before it is erased so you retain an electronic copy of what was erased. It also separates out paper which cannot be erased completely such as paper that has regular toner or permanent ink applied.
You can print and erase the same sheet of paper up to 5 times according to Toshiba and you can print it with regular ink or toner such as the black toner that is also available in the STUDIO 4508LP. Reportedly the machine costs $15,420.
One of the best features of this system from Toshiba is that it uses regular paper so the eco benefits of reusing the paper are in addition to (rather than replacing) the benefits of eco-friendly paper and recycling. The trade-offs are being able to print only in blue and having to use a special printer priced above what individuals and smaller workgroups may want to spend.
Laser De-printing (Reep)
A completely different approach is to remove ink and toner from a sheet of paper by vaporizing it with a laser. Reep is planning to commercialize their Circular Print service that includes laser “de-printing” devices and re-printable papers which are optimized for 10X re-printing on the same sheet (or more) without damage during the laser de-printing process. Here is an example where the middle of the page has been de-printed by Reep’s machine. This image is from a BBC video about the technology:
The de-printer device should be able to completely erase print from any existing print method so it would be compatible with the installed base of printers of all brands. This is one of its strongest capabilities since printing is not limited to a particular color or printer and there should be few if any compromises in print quality. It also provides security by eliminating the need to shred sensitive documents after use. Vaporized toner is captured and could potentially be recycled back to make new toner. The company’s strategy is to provide their re-printable papers and de-printing devices to organizations as a Circular Print service. The concept and technology of laser removal of ink have a history dating back at least a decade in both university settings and in the private sector, and Reep has worked to overcome previously limiting factors of quality, security and economics.
The best features of Reep’s Circular Print service are that it is compatible with any existing print method and provides excellent document security. The main trade-offs are that it does not use regular paper, and the pricing and final specifications are unknown.
Recycled paper-making machine (Epson)
Epson’s Paper Lab is a large machine is a machine that breaks down paper into fibers and makes new paper, on-demand and in-house. As shown in these images from an Epson video
Printed paper goes in:
And recycled paper comes out:
The PaperLab breaks down printed paper into tiny fibers, removes most of the ink or toner, and then adds a binder and colorants to make new white or colored paper. Their process uses only minimal water in comparison to conventional paper recycling.
As in conventional recycling, the same paper cannot be recycled indefinitely because the paper fibers become shorter every time. From the specifications, the paper fed into the PaperLab is limited to no more than 10% paper that was produced earlier by the PaperLab machine. The thinnest paper the machine can produce is 90 gsm (24#) which is thicker than the most commonly used 75 gsm (20#) office and copy paper. In terms of paper re-use that means a sheet of paper can be reused one time on average. The amount of energy required by the PaperLab machine is negligible compared to the energy to produce a sheet of regular recycled paper.
The Paper lab machine can produce 12 sheets of paper per minute. Reportedly the machine can be leased for about $5900 per month which includes all supplies.
The best features of the Epson PaperLab seem to be that it works with regular paper (like the Toshiba system) and that, like the Reep system, it is compatible with any existing print method and provides excellent document security. The main trade-offs are that paper re-use is limited to one time, it is large (2.85m wide, 1.43m deep, 2.01m high, and 1,750kg) and it is expensive. If you ran the machine 40 hours per week the paper produced would cost about $25 per 500 sheet ream based only on the cost of leasing the machine.
Thermal Papers (Experimental)
Another approach that has been explored is to replace paper with sheets of reusable display material that is “printed” by heat or light and erased by heat. It is unclear if any of these systems are commercially available today but there have been many prototypes. In 2001 Ricoh demonstrated a “Rewritable Printing System” as shown in this photo from a 2002 Ricoh technical report:
Ricoh made their “paper” out of thin sheets of plastic with embedded dyes which would become visible if heated above a certain temperature and then rapidly cooled. The dyes could be erased when heated to a temperature not as high and allowed to cool more slowly. It does not appear that this system reached the market to replace printing on office paper but Ricoh does market a similar technology for re-writeable plastic cards, labels and barcodes.
The “Prepeat” from Sanwa-Newtec used the same technology as shown in this image from a diginfo tv video:
At the time the printer was reported to cost about $5,600 and the “paper” about $3.30 per sheet, with reuse of up to 1000 times possible. It is not clear how long the printer was on the market but it no longer seemed to be featured on the company website in 2011.
Xerox prototyped a similar “paper” around 2006. This image was taken from a BNET video:
The “paper” was yellow and contained a material they compared to the material in sunglasses that turn dark outside. The material was “printed” by exposing to UV light from LED’s and erased naturally over about 24 hours or immediately with the application of heat. It never made it to market.
The most straightforward and effective way to cut paper usage is not to print or make copies. However, the “paperless office” predicted in 1975 has still not become universal because printing is still quite useful to some. Since printing is here to stay, it is encouraging that so much work has gone into applying the principles of re-use and circularity to printing. The erasable toner from Toshiba, de-printing and re-printable paper from Reep, and the paper-making machine from Epson, along with paper substitutes, all represent ambitious efforts to change the way we use paper and get away from our use of paper as a disposable, single-use product. In Part 2 of this series, I will share more details about the environmental benefits of paper re-use and my own work on a lower-cost technology to achieve these benefits.