A colour-changing ink that can expose the fakes from the original
In a boost to the fight against the menace of counterfeiting, two researchers at the Hyderabad campus of the Birla Institute of Technology and Science have developed an ink that changes colour when exposed to acid vapours and reverts to its original colour when exposed to base vapours.
The ink contains small amounts of what are called fluorophore particles made from a chemical called ‘mono-carbazole-linked anthranyl π-conjugates.’ Fluorophore particles are invisible under normal light but light up with a yellow colour when exposed to a commercial ultraviolet light torch. The ink is found to be stable under ambient conditions and up to a temperature of 300 degrees C.
“We tested our yellow coloured fluorophore along with many other conventional yellow fluorophores used in many applicat...









