Ink dating, part I: Statistical distribution of selected ageing parameters in a ballpoint inks reference population

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Serval ID
serval:BIB_FFCFCAC5BBC0
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Ink dating, part I: Statistical distribution of selected ageing parameters in a ballpoint inks reference population
Journal
Science & Justice
Author(s)
Koenig Agnès, Weyermann Céline
ISSN
1355-0306
Publication state
Published
Issued date
01/2018
Peer-reviewed
Oui
Volume
58
Number
1
Pages
17-30
Language
english
Abstract
The development of ink dating methods requires an important amount of work in order to be reliably applicable in practice. Major tasks include the definition of ageing parameters to monitor ink ageing. An adequate parameter should ideally fulfil the following criteria: it should evolve as a function of time in a monotonic way, be measurable in a majority of ink entries, be as accurate and reproducible as possible, and finally it should not be influenced too much by transfer and storage conditions. This work aimed at evaluating the potential of seven ageing parameters for ink dating purposes: the phenoxyethanol quantity, relative peak areas (RPA), three solvent loss ratios (R%, R%*, NR%) and two solvent loss parameters (RNORM, NRNORM). These were calculated over approximately one year for 25 inks selected from a large database to represent different ageing behaviours. Ink entries were analysed using liquid extraction followed by GC/MS analysis. Results showed that natural ageing parameters (NR% and NRNORM) were not suitable ageing parameters for ink entries older than a few weeks. RPA used other compounds present in ink formulations in combination to PE in order to normalise the results. However, it presented particular difficulties as they could not be defined for all inks and were thus applicable only for 64% of the studied inks. Finally, the PE quantity, R% and RNORM allowed to follow the ageing of the selected inks over the whole time frame and were identified as the most promising. These were thus selected to test three different interpretation models in the second part of this article. The possibilities and limitations of ink dating methods will be discussed in a legal perspective.
Keywords
Questioned document, Ink analysis, Ink dating, Ageing parameters, Statistics, Interpretation, Pathology and Forensic Medicine
Web of science
Open Access
Yes
Create date
23/06/2015 14:33
Last modification date
20/08/2019 17:30
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