Chinese scientists in U.S. invent smart ink helpful for anti-counterfeiting

Two Chinese scientists doing research at a chemistry lab at the U.S. Northwestern University -- Chenfeng Ke and Xisen Hou -- have developed a smart ink for printing multicolored watermark that only shows up under UV light.

According to the researchers, the watermark is derived from a special formula that is near-impossible to reverse engineer, making it difficult for counterfeiters to copy products.

"Producers normally want to make sure only they know the formula, and only they can verify the information." said Ke.

The ink is invisible to the naked eye, but when put it under ultraviolet light, the ink glows into anything from a bar code to a picture of the product itself.

Ke demonstrated the ink for Xinhua reporter with a color palette and a painting of a field. "Under dark it's more vivid even, so you can have red, to yellow, to greenish, to blue, to some purple colors." Ke said.

The process used to make the ink allows producers to create a recipe that is difficult to change. "You add all the ingredient and the solvent, and you just put it onto a hot plate, this is a condenser, assemble that, and clamp it tight, and you turn on your hot plate," Hou said.

Ke and Hou accidentally discovered this method after trying to create a chemical that could be used in a display. After one experiment, they expected to find green, but instead found orange, leading to the discovery of the changeable formula.

In addition to being extremely difficult to reverse-engineer, Ke says that manufacturers can create a spray that will change the color of the ink after it has been applied, as another layer of anti-counterfeiting protection.

The International Anti-Counterfeiting Coalition, a lobbying group, estimates that almost 600 billion U.S. dollars are lost each year to counterfeiting internationally. Endi