Chemical Ink Examination - Chemical Ink Dating
Dating a document can be done by the chemical analysis of the inks used to prepare the document including writing and printing inks. The chemical analysis of inks for the purpose of dating the inks is a very specialized sub-discipline of forensic document examination. Ink dating is one of the most trustworthy methods to assist in determining the age of a document.
The chemical analysis of inks can assist in the following ways:
Numerous inks can be chemically associated with other inks to confirm or disprove whether the entries were written contemporaneously
Inks go thru a drying process that takes approximately two (2) years. Chemical components of the inks that carry the in to the paper evaporate over the two (2) year period. Using a generally accepted procedure, the chemist uses a gas chromatograph/mass spectrometry (GC/MS) to identify the amount of solvent remaining in the ink to determine the age of the ink up to a two (2) year period.