Chemists unveil 'water-jet' printer

2014-01-28 21:08

Multimedia   ·   User Galleries   ·   News in Pictures Send us your pictures  ·  Send us your stories

kalahari.com

  • Chinese Culture
    Read all you need to know about the Chinese culture in this insightful title. Now R447.00
    buy now

Paris - Like any ordinary printer, this machine ingests a blank page and spits it out covered in print.

But instead of ink, it uses only water, and the used paper fades back to white within a day, enabling it to be reused.

A team of chemists claims their "water-jet" technology allows each page to be reprinted dozens of times - a money- and tree-saving option in a digital world that still relies heavily on hard copy.

"Several international statistics indicate that about 40% of office prints [are] taken to the waste paper basket after a single reading," said Sean Xiao-An Zhang, a chemistry professor at Jilin University in China, who oversaw work on the innovation.

The trick lies in the paper, which is treated with an invisible dye that colours when exposed to water, then disappears.

The print fades away within about 22 hours at temperatures below 35°C as the water evaporates - quicker if exposed to high heat, Zhang and a team wrote in a paper describing their invention in the journal Nature Communications.

The print is clear, claim the designers, and the technology cheap.

"Based on 50 times of rewriting, the cost is only about one percent of the inkjet prints," Zhang said in a video on the Nature website.

Even if each page was re-used only a dozen times, the cost would still be about one-seventeenth of the inkjet version.

Sean said dye-treating the paper, of the type generally used for printing, added about five percent to its price, but this is more than compensated for by the saving on ink.

Replace ink

Crucially, the new method does not require a change of printer but merely replacing the ink in the cartridge with water, using a syringe.

"Water is a renewable resource and obviously poses no risk to the environment," said the study.

Previous work in the quest for a disappearing ink has tended to yield a low-contrast print, often at a high cost, and sometimes using hazardous chemicals.

Zhang and his team used a previously little-studied dye compound called oxazolidine, which yielded a clear, blue print in less than a second after water was applied.

They have managed to create four water-printed colours so far - blue, magenta, gold and purple - but can only print in one hue at a time, for now.

The next step is to improve both the resolution and the duration of the print.

They are also working on a machine that will heat pre-printed sheets of paper as they are fed into the machine, fading the pages instantaneously for re-printing.

At 70°C, the colour disappears within about 30 seconds.

Zhang said the dyed paper was "very safe" but toxicity tests are under way on mice to be sure.

Read more on:    nature journal  |  china  |  technology
NEXT ON NEWS24X
SHARE:

Read News24’s Comments Policy

24.com publishes all comments posted on articles provided that they adhere to our Comments Policy. Should you wish to report a comment for editorial review, please do so by clicking the 'Report Comment' button to the right of each comment.

Comment on this story
3 comments
Add your comment
Comment 0 characters remaining
 

Inside News24

 
/News
 

Get fit on a budget

It’s time to throw the “I can’t afford to exercise” excuse out the window.

 
 

Where were you when you last felt alive?

Tips for paddling your first Dusi
Climbing the world’s largest stone arch
Awesome extreme sports people
Watch: 2015 Absa Cape Epic route

Jobs in Cape Town [change area]

Property [change area]

Travel - Look, Book, Go!

Magical Massinga

Spend 5 nights at the gorgeous Massinga Beach Lodge in Mozambique and only pay for 4 from R13 220 per person sharing. Includes return flights, accommodation, transfers and romantic turndown. Book now!

Kalahari.com - shop online today

Seen something you like in our catalogue?

Find the perfect gift and save up to R5000 – As seen on the catalogue. Hurry and shop now!

Save up to R1000 on Hisense smartphones!

View the large range of Hisense smartphones. Buy today and save up to R1000!

Toys 4 for the price of 3

Buy 4 toys and get the cheapest FREE! Offer valid while stocks last. Shop now!

Mind blowing prices – As seen on TV

Get mind blowing prices on 1000’s of products! Shop now.

Deal of the week!

Save R1200 on the Samsung 48” smart full HD LED television now only R8799. Buy now!

OLX Free Classifieds [change area]

Samsung Galaxy s4

Mobile, Cell Phones in South Africa, Western Cape, Cape Town. Date October 24

Best bargain in big bay

Real Estate, Houses - Apartments for Sale in South Africa, Western Cape, Cape Town. Date October 25

VW Golf 6, 1.6 Trendline (Excellent condition)

Vehicles, Cars in South Africa, Western Cape, Cape Town. Date October 25

Horoscopes
Aquarius
Aquarius

You may prefer to be in charge because then you can call the shots. You are not as flexible as you like to make out to be and you...read more

There are new stories on the homepage. Click here to see them.
 
English
Afrikaans
isiZulu

Hello 

Create Profile

Creating your profile will enable you to submit photos and stories to get published on News24.


Please provide a username for your profile page:

This username must be unique, cannot be edited and will be used in the URL to your profile page across the entire 24.com network.

Settings

Location Settings

News24 allows you to edit the display of certain components based on a location. If you wish to personalise the page based on your preferences, please select a location for each component and click "Submit" in order for the changes to take affect.








Facebook Sign-In

Hi News addict,

Join the News24 Community to be involved in breaking the news.

Log in with Facebook to comment and personalise news, weather and listings.