Ballpoint ink dating heating
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.
Iron-based inks can be dated by measuring the migration of iron along the fibers of the paper by Scanning auger microscopy.
This article describes state of the art procedures for the chemical and physical comparison, identification and dating of inks on questioned documents.
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.
While in this case, 2 of the 3 dye-ratios calculated reflect a difference, only a difference in one dye-ratio is necessary to establish that the age of the ink is different GRAPH 2 Experiment 3- Percent Extraction For this experiment a Bic black ball point ink was used.
Seven samples of ink written on copy paper and ranging in age from fresh to 13 months were analyzed. Experimental variation for the 10 and 13 month old samples makes these two ink samples indistinguishable.