The money detector uses powerful UV illumination to make the security thread visible on even the most worn or faded bills. (Photo : www.count-money.com)
Two Chinese scientists at Northwestern University in the U.S. have reportedly developed a smart ink that can be used for printing multicolored watermark, the Xinhua News Agency reported.
According to the report, Chenfeng Ke and Xisen Hou have developed the ink while doing research at the chemistry lab in the university. The watermark only shows up under UV light and was taken from a special formula that cannot be changed using reverse engineering or cannot be copied by counterfeiters.
"Producers normally want to make sure only they know the formula, and only they can verify the information," Ke was quoted as saying.
The report said that the ink is invisible to the naked eye and shines under ultraviolet light.
Ke made a demonstration of the ink using 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 report added that the two scientists used a process that allowed them to create a formula 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 explained during the demonstration.
The report said that the two scientists had accidentally discovered this method while trying to create a chemical that they can use in a display. In one experiment, they expected to find green, but instead found orange, which led to the discovery of the formula.
Aside from being difficult to reverse-engineer, Ke said that manufacturers can create a spray to change the color of the ink after it has been applied to make another layer of protection.
According to the International Anti-Counterfeiting Coalition, nearly $600 billion are lost every year due to global counterfeiting activities.
