This is the opposite of most inks which usually extract slower as the ink ages.GRAPH 3 Experiment 4- R-Ratios on a Papermate Black Ball Point Ink Known dated inks written in 1992, 1993, 19 on bond paper were analyzed using the R-Ratio method.Graph 4 below shows the results that all of these inks were distinguishable as to age.Note the 3 minute extraction time is missing for the 1992 sample, because the pipette was dropped.Comparison of these chemical and physical properties of two or more inks can determine: (1) if the inks were made by the same manufacturer; (2) in some cases, whether the inks are products of the same production batch; and (3) the first production date of the specific ink formulation involved.
Chemical and physical analysis of inks on questioned documents provides valuable information regarding their authenticity.
Opinions of ink dating chemists, both government and private, differ on the reliability of the above described ink aging methods.
Therefore, before applying any of these methods to actual case work the author conducted an independent evaluation of the reliability of the R-Ratio, Percent Extraction, Dye-Ratio and Accelerated Aging techniques for estimating the age of writing ink on documents.
Dating tags are unique chemicals that have been added to ball-point inks by some ink companies as a way to determine the year the ink was made.
Relative age comparison tests performed on inks of the same formula and written on the same type of paper with the same storage conditions (performed by measuring changing solubility properties of inks) can estimate how long inks have been written on paper.