New printer uses water instead of ink

Saturday, February 22, 2014 by: J. D. Heyes
Tags: water-jet printer, ink, rewritable paper

(NaturalNews) Soon, if Chinese researchers are successful, the world's printers won't use environmentally unfriendly ink - they will use water.

Many people find it much more difficult to read from a brightly lit computer screen. For them, there is nothing like the feel of paper in hand. Plus, printing stories, reports or other items allows you the freedom to move away from your brightly lit screen and take your printed copy with you or relax somewhere while reading.

But that presents a dilemma, especially if you're environmentally savvy and in tune. Up to 40 percent of office documents are printed merely for one-time use, which means that a lot of resources - paper and expensive ink - can be wasted or, at best, used very inefficiently. That makes this an area ripe for change.

According to the tech site Gizmodo, there is a solution on the horizon:

Chinese researchers say they may have come up with just the thing to ease the conscience and lower the cost of reading documents on paper. They've created a jet printer that uses water instead of ink and a complimentary reusable paper that changes color while it's moist.

"We all know we are facing many problems. Three major problems are the energy crisis, global warming and ecological and environmental deterioration," said Sean Zhang, a Jilin University chemistry professor and coauthor of a study on the innovation, which was published in the journal Nature Communications in late January. "All of these three problems are caused by one main factor: deforestation. Excess paper consumption contributes greatly to deforestation."

Water activates rewritable paper

The U.S. Environmental Protection Agency says Americans generated some 70 million tons of paper and paperboard refuse in 2011. Total world consumption of paper amounted to about 400 million metric tons in 2012, estimates the Swedish Forest Industries Federation.

But now, Zhang maintains that he and his team are devising a way to dramatically reduce that amount of consumption using water-jet rewritable paper, which can be printed upon and then erased a number of times.

The researchers say the paper is made with dyes that are invisible when dry but reveal colors when wet. Water, therefore, serves as the primary activator for the dye, opening previously closed and colorless molecules when water triggers coloration.

Testing has shown that each sheet of the special paper can be reused as many as 50 times. The researchers used a standard desktop printer whose ink cartridge they had filled with plain water.

The technology was also demonstrated using a water-filled pen; it temporarily recorded handwriting in the same manner using the same colorization principle.

"So far, we've already achieved four different colors and the prints can last for 22 hours," Zhang says. "The quality of the water-jet printing is comparable with ink-jet printing."

'We also solve the problem of paper waste'

In their research paper, the team said they hope to make improvements to what has already been accomplished.

"The legibility and resolution of our current water-jet prints seem good enough for general reading purpose, and we are confident to improve further the colour intensity and evenness of our rewritable media," they wrote.

Because the paper is reusable, and water is much cheaper than ink, the research team said that water-jet printers should only carry about 1 percent of the cost per page of traditional ink-jet printers.

Also, the researchers have run toxicity tests and have found that the water-reactive dyes do not pose safety risks, though extended exposure testing using mice is currently underway.

"Even though we are in the electronics stage... people prefer hard-copy reading," Zhang said, according to Gizmodo. With the water-based printing system, "we are not only saving a lot of money, we also solve the problem of paper waste."

Sources:

http://www.gizmodo.com.au

http://www.geekosystem.com

http://www.scmp.com