Comparison of the main dating methods for six ball-point pen inks

Application of chemometric methods for the determination of fading and age determination of blue ballpoint inks

“…The last group is called dynamic dating methods, because they specify changes in the concentration of one or more components of the inks over time. [ 7 ]…”

“…[6] The study of the ink, namely, its differentiation and dating, is one of the most appealing challenges of forensic studies. About 28 methods of dating ink [2,[6][7][8][9][10][11][12][13] have been proposed since 1984. Several factors are involved in ink ageing, and the proposed models have only taken into account some of them [13] ; moreover, the models have several limitations and work properly for only few types of inks.…”

“…The advances in the ink dating field and development of analytical methods observed in the last decades were reported by Ezcurra et al [11] In the case of ballpoint pen inks, methods for determining the approximate or relative age of an ink are commonly divided into three groups. [7] The first group includes static dating methods based on the analysis of materials, like paper or writing ink, which might be characterized by the specific technical developments introduced by the manufacturer at a specific date. [3,14] For example, phthalocyanine (Pigment Blue) was introduced to the production of inks in 1954, so its identification in the analysed ink may help to date the document.…”

“…The last group is called dynamic dating methods, because they specify changes in the concentration of one or more components of the inks over time. [7] Most of the currently developed dating methods are based on gas chromatography/mass spectrometry (GC/MS) technique and rely on the determination of the loss of ink volatile components. [3,16,17] Those components diminish over time, and most of them will evaporate very quickly after being deposited on the support (e.g., it takes from minutes to 1.5 or 6 months depending on solvents and conditions [2,3,14] ).…”

Experimental Research on Class Identification with a New Type of Erasable Gel Pens

“…While this is still destructive, the use of optical methods can better ensure the integrity of the documents. The modern evidence identification requirements ensure the integrity of the questioned documents, so the optical analysis methods that are nondestructive examination for the questioned documents are obviously more in line with the requirements of the current forensic examination for physical evidence .…”