Kinetics comparison for the different variants of artificial aging of handwritten strokes by the method of high-performance liquid chromatography with mass-spectrometric detection

Abstract

In the judicial practice, the problem of documents falsification by artificial aging is encountered quite often. Artificial aging can be accomplished by the prolonged exposure of the documents to the elevated temperatures from the household heating devices (e.g. oven, iron), microwave radiation from a household microwave oven, or ultraviolet radiation from an ultraviolet lamp for manicure purposes. Therefore, it is relevant to develop approaches for recognizing the acts of falsification using the modern physical and chemical methods. The purpose of the current research was to identify the changes that occur with the ink dyes of blue color ballpoint pens over time under the influence of elevated temperatures, as well as to compare the obtained results with the data attained by the exposure to the UV radiation. As an outcome of this work, the possibilities of chromatography-mass-spectrometric detection of changes in the composition of ballpoint pen inks of BIC Original, Corvina 51 and Pilot brands after their exposure to the elevated temperatures and UV radiation were estimated. The curves of the dyes for the artificial aging for the three different ballpoint pen inks were obtained from the time of exposure to UV radiation at 365 nm and heating at 100, 130 and 150˚C respectively. A comparison of the processes of the dyes degradation when exposed to UV-radiation and thermal action on handwritten strokes was carried out. It was shown that for the established intensity of UV radiation, the gentlest type of documents aging was holding the stroke samples at a temperature of 100˚C for 36 hours. Keywords : handwritten stroke, ballpoint pen ink, aging of strokes, artificial aging, liquid chromatography, mass-spectrometry. (Russian) DOI: http://dx.doi.org/10.15826/analitika.2019.23.1.003 D.I. Baygildieva, T.M. Baygildiev, О . А . Shpigun, I. А . Rodin Lomonosov Moscow State University, Leninskie gory, 1, Moscow, 119991, Russian Federation