A common request made to forensic document examiners is to ‘date’ a signature or handwritten entries in a medical file, diary, etc. The ink dating process is a specialized area requiring the expertise and laboratory instruments of an ink chemist. Ink samples must be taken from the page and the components analyzed to determine the manufacture and date of the inks’ introduction to the market. Because of the physical removal of the ink from the paper (by micro-punches), it is considered a destructive process. However, ink chemists are careful to take the necessary samples and leave an ample amount of ink for a subsequent examination by an opposing chemist.
One process used to determine if a ‘self serving’ entry was added to a document, is an analysis of the evaporation rate of ink. Ink recently placed on paper will have a higher evaporation rate than ink placed on the same page several months or years prior.
The majority of document examiners do not have the sophisticated laboratory equipment to date ink but will be able to provide the name of a reputable ink chemist.