Despite these recent methods, several questions remain.
The R-Ratios technique easily distinguished the age of these inks. The first ink dating method is the static approach, which determines when the ink being examined was manufactured.However, the 0 to 5 month old samples are clearly different from the 10 and 13 month old samples.It is interesting to note that this Bic black ball point ink written on copy paper extracted faster with age.The inks were written on copy paper during 1993, 19.
Graph 2 below shows that the 19 inks were not distinguishable using the dye-ratio method; however, the 1993 ink is clearly different than the other two.
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.
Then the rate of extraction and percent of extraction comparisons were made as listed above.