Comparison between blue ballpoint pen and blue gel pen inks using stereomicroscopy, video spectral comparator, atr-ftir, thin layer chromatography and chemometrics technique
Pens have been used as tools to make alterations on documents during the act of forgery. The emergence of hybrid pen inks which exhibits both characteristics of gel pen and ballpoint pen inks has imposed challenges to ink discrimination. Therefore, this study aims to compare the physical and chem...
| Main Author: | |
|---|---|
| Format: | Monograph |
| Language: | English |
| Published: |
Universiti Sains Malaysia
2016
|
| Subjects: | |
| Online Access: | http://eprints.usm.my/62621/ http://eprints.usm.my/62621/1/LINTHINI%20GANNETION%20-%20e.pdf |
| Summary: | Pens have been used as tools to make alterations on documents during the act of
forgery. The emergence of hybrid pen inks which exhibits both characteristics of gel pen and
ballpoint pen inks has imposed challenges to ink discrimination. Therefore, this study aims
to compare the physical and chemical characteristics of blue ballpoint pen inks and gel pen
inks of similar hue through their ink profiles generated by four different techniques, namely
microscopy, video spectral comparator (VSC), ATR-FTIR and thin layer chromatography
(TLC). Ten blue ballpoint pens and ten blue gel pen inks were chosen randomly regardless
of brands. Optical examination using stereomicroscope and VSC-6000, ATR-FTIR
spectroscopy as well as thin layer chromatography using two different solvent systems were
employed to analyse all ink samples. Results of ATR-FTIR and VSC microspectroscopy
were statistically analysed using principal component analysis (PCA) and hierarchical cluster
analysis (HCA) respectively to ease comparison and discrimination. The results show that the ink profiles of the pens which were created by combining the microscopical characteristics, fluorescent characteristics, FTIR spectra, ink solubility and combination of
colourants used (dye or pigments) in gel pens and ballpoint pens vary despite the fact that all
the pens visually appear to be of the same colour. This indicated that a combination of
techniques provided better discrimination among the samples tested. |
|---|