New printing technique uses water instead of ink

A new innovation which uses water instead of inkjet ink may help reduce our paper waste.

It’s all possible when printing on paper treated with an invisible dye. The dye becomes visible when exposed to water, then fades away within a single day. This allows the paper to be reused instead of discarded.

The longevity of the print depends on temperature. As the water evaporates, the print fades – all within 22 hours, if temperatures are below 35°C (95°F). Higher temperatures decrease the duration of the print visibility: 70°C (158°F) will cause the dye to disappear within about 30 seconds. This means a page could easily be wiped clean using a heat source.

But who needs a printed page for only a day? Sean Xiao-An Zhang (chemistry professor at Jilin University in China who oversaw the project) says:

Several international statistics indicate that about 40 percent of office prints (are) taken to the waste paper basket after a single reading.

There’s no need to purchase a new printer: just replace the ink in your current cartridge with water injected using a syringe. If a page of paper is reused and rewritten 50 times, say Zhang, the cost is reduced to 1% the cost of inkjet prints.

Dye-treating the printing paper only increases its cost by about 5%. The dyed paper is “very safe,” says Zhang, but is still being tested for toxicity.

Via: The Bangkok Post