NCJ Number
141640
Date Published
1991
Length
28 pages
Annotation
This report describes the methodology and results of a project designed to determine the age of a document by extraction and subsequent analysis of ink.
Abstract
The analytical aspect of the work used techniques such as gas chromatography, Fourier Transform Infrared Spectroscopy (FTIR), and High Performance Liquid Chromatography (HPLC). The FTIR showed no significant differences between extracts of the same ink and was therefore discontinued. Gas Chromatography-Mass Spectrometry (GC-MS) showed some promising results, thus allowing not only the quantitation of volatile solvents in the extracts, but also structural identification of certain ink components. The only limitation of this particular approach was the lack of sensitivity of this particular mass spectrometer (50-100ng/ml), thereby requiring the use of large sample sizes. HPLC analysis of supercritical fluid extracts resulted in the greatest amount and most useful information. It revealed differences in the profiles of inks of different ages. Thus, supercritical fluid extraction at different pressures followed by HPLC analysis has significant potential for the determination of the age of a document. 18 references and 8 figures