Paper Doesn’t Have To Be Disposable (Part 2)
In Part 1 of this series, I shared some exciting technologies that make paper reusable. Part 2 is going to be a little more personal, covering the paper-reuse technology I invented and why this is good news for the planet.
Origins of Blue Planet Ink
One night I was having a conversation about the pros and cons of paper. I remember thinking that, ideally, when you were done with a sheet of paper the printing would magically disappear and the paper would be brand new again. I thought you could get close to that ideal by printing with disappearing ink using an inkjet printer. Disappearing ink for printers seemed like an obvious idea, so the next morning I searched the internet to buy some. I thought I had found a source, but when I made an inquiry it turned out that they only sold invisible ink that could be revealed with UV light. I shifted my search to patents and surprisingly found that there weren’t any patents on disappearing ink for printers either. I knew that I could buy disappearing ink for magic tricks, so I bought some and tried it in a printer. It didn’t work at all, but I was hooked on the concept and decided to try to make it myself.
Fairly quickly I was able to make a crude disappearing ink that was good enough to demonstrate in a printer.
After a few more years I was granted a patent for a “Self-erasing printing system”. I hoped to license the idea to one of the existing printer companies to further develop and bring to market, but soon found out they did not want to take that risk. They also probably had a better understanding than I did at the time of how difficult it would be to make the ink work without clogging or damaging the tiny nozzles in print heads. However, with a lot of work, help from others, and a little luck I was able to make the idea a reality and start a company called Blue Planet Ink® which began selling Paper Saver® self-erasing inkjet ink at the end of 2019.
Paper printed with Paper Saver ink returns to a blank state because the ink becomes colorless. The ink is still on the paper but is completely invisible. Some people who have taken a Chemistry class may remember that there are substances called pH indicators which change color depending on whether a liquid is alkaline (higher pH, such as dishwasher soap) or acidic (lower pH such as lemon juice). Paper Saver ink uses an indicator that changes from purple in an alkaline solution to colorless as the ink loses alkalinity. The ink starts out alkaline, purple, and visible. After printing it absorbs carbon dioxide and water vapor from the air. The water and CO2 react with the ink to make it less alkaline, colorless, and invisible.
The time it takes for the ink to self-erase depends on how much the printing is exposed to air flow, how much water is in the air (humidity), and how much ink there is on the page. A single page of text left out on a table overnight might be completely erased by the next morning.
On the other hand, a page with lots of dark graphics left in the middle of a tall stack of paper could take about three weeks to erase. When people ask me how to make the ink erase faster so they can reuse the paper immediately, my advice is not to worry about reusing a particular sheet of paper as soon as possible. Instead, just put the printed paper on top of a stack in a tray somewhere and forget about it.
Then when you need new paper, take the oldest paper from the bottom of the stack and use it as you would new paper.
You can print it over and over with self-erasing ink as many times as you want. Or you can print it with regular ink or toner, or use it for handwriting, drawing, or for anything else instead of new paper. At some point, if a sheet becomes too wrinkled or otherwise damaged, you can then recycle it as you would any other used paper.
Keeping it simple
The ink has some limitations. First of all it is only one color, and an unusual color at that. At the beginning I wanted to make the ink in the familiar black color but that was not possible with known chemistry. I also tried blue and even named the company “Blue Planet Ink”. But I found that purple ink could work with less alkalinity which made it more reliable in printers, and safer if people got it on their skin. Purple ink became the standard. Later I came to realize that a black disappearing ink would have been a bad idea. Disappearing ink would have been mistaken for regular ink, and black would have been a lot easier to use for deception which certainly did not fit into my goal of trying to do good for the planet.
Another limitation of the ink is that the erasing time varies. You can’t control or predict exactly when it will erase. I thought a lot about ways I could make erasing nearly instant and on demand like so many other things we have now. Perhaps I could create an erasing machine or paper coatings and chemical treatments that would make erasing more controlled. However, I decided to keep things simple. If I added an erasing machine, how much energy would it take to manufacture and operate? If I were not careful, or made a miscalculation, the erasing technology could do more harm to the environment that the good that came out of reusing paper.
I felt that the way to ensure that the environmental benefits of Paper Saver ink outweighed the environmental costs was to keep it as simple as possible. I would make it work with plain paper and regular printers and only substitute my ink for regular ink. Then the benefits of reusing paper would be in addition to rather than in place of improvements in paper and printer sustainability made by others. This approach is also the most affordable for the user since they have to buy ink or toner anyway.
Paper is the problem in printing
Why does saving paper matter? A sheet of paper seems pretty insubstantial compared to a printer made of plastics and metals and running on electrical power. However, almost all the environmental impact of printing is from the paper. [source#1 source#2]
The carbon emission from a mere 12 sheets of paper is as much as driving a car one mile.
And did you know that making a sheet of paper uses 1500 times more energy than printing that sheet of paper?
Here is how new paper impacts the environment compared to re-used paper: source ink
Reused paper is free paper and has zero effect on the environment!
Shouldn’t we just stop printing?
Certainly, from a purely environmental perspective, it would be best if we just stopped printing. It would also be best if we stopped driving, stopped eating meat, stopped producing plastics, etc. But while we are working towards eliminating these activities it makes sense to make them less harmful. Printing and copying haven’t gone away yet. Paper documents are still useful tools to many, despite the extra steps and expense involved compared to just reading documents on a screen. The COVID-19 pandemic demonstrated just how important printing remains to many. When people began working from home during the pandemic, there was a huge surge in printer sales!
Blue Planet Ink is still a small business, but I believe we have already done some good for the world. We will be able to do more as we make the ink available for more printer models. Back in January 2022 we only offered 1 ink cartridge model and only 4 bottled inks tank printers. But that month alone the ink we sold could save enough paper to stack higher than the Leaning Tower of Pisa!
We’ve sold Paper Saver ink to people in 34 countries so far with sales in Europe being particularly strong.
It is exciting that so many people have found our website and joined the paper re-use movement. I hope that what Blue Planet Ink has to offer, along with the technologies discussed in Part 1, will help shift paper towards being reusable and away from being disposable.