Specifically, they focussed on the solvent known as 2-phenoxyethanol (PE), present in 80% of the inks in ballpoint pens of this type.
Itxaso San Román, Luis Bartolomé and Rosa María Alonso allowed the chemical compound to age under normal conditions, without ageing it artificially, which is what happens in other methods, and studied its evaporation speed.
Aware of these difficulties, the UPV/EHU team began to work on samples written for research purposes.
To do this, they used BIC® ballpoint pens, one of the most common makes and, therefore, the most widely used in documents subjected to legal examination.
Unlike the large quantity of sample required by other traditional methods to age the compounds artificially and analyse them, the technique developed in the UPV/EHU labs allows the document to be dated using a single puncture and without altering the compounds. DATINK pilot study: An effective methodology for ballpoint pen ink dating in questioned documents, Archeologists have uncovered a large Bronze Age city not far from the town of Dohuk in northern Iraq.