John Allison, professor of chemistry, received a $261,000 grant from the Department of Justice/National Institute of Justice for research on pigmented ink. Because this ink cannot be dissolved in water, the FBI is trying to find ways to both take advantage of it and overcome the obstacles it presents.
Take, for instance, the offense of “check washing,” committed all over the country. When dyed inks were used on checks, people could use household chemicals or even water to wash checks and reuse them.
Pigmented inks have eliminated the problem because the particles are not liquid soluble. However, they have also created complications, which are what Allison hopes to help resolve with his research.
Since pigmented ink cannot be dissolved in water, law enforcement agencies cannot use chromatography, the method usually used to identify inks, on documents that use it.
“The FBI depends on chromatography . the FBI has thousands of records on inks from different pens and companies,” Allison said.
According to Allison, these records could be used for anything from tracing a ransom note to identifying handwriting. His research is focused on finding ways the FBI can duplicate this process with pigmented inks.
Ultimately, his goal is to make pigmented ink more mainstream.
Though the ink is used in forensic efforts and by antique experts, it does have qualities that will appeal to the public. As many companies have marketed, the particles never run and do not fade in the sun.
According to Allison, Hewlett Packard is going to launch an ad campaign for pigmented ink cartridges that print pictures that last for a century.
Pigmented ink suspends particles of color in a liquid. When used, the liquid allows the particles to be spread as needed, and then the liquid evaporates, leaving the color particles behind, a process very similar to that of paint.
“We have a technique called laser disorption mass spectrometry . we can take a piece of paper and focus a laser on the pen stroke and vaporize the particles. Once the pigments are ionized, molecular information can be used to help identify the ink,” Allison said.