Analysis of the Chemical Composition of Red Pigments and Inks for the Characterization and Differentiation of Contemporary Prints

Abstract

Prints are one of the most popular artistic forms. They consist of an original matrix that is printed on a paper support. The stamps are part of a series, and each series is composed of a particular number of prints. Many contemporary prints are made using oil inks and synthetic pigments (reds and yellows). Inks are mainly composed of pigments (organic or inorganic) and a binding medium. The analysis of inks has the potential to facilitate and complement the identification of stamps of different origins.Fourier transform infrared spectroscopy (FTIR) and Scanning Electron Microscopy-Energy Dispersive X-ray (SEM-EDX) are techniques that are typically available in museums and centers related to the study of works of art. Both can be classified as micro-destructive and provide complementary information about the organic and some inorganic compounds (FTIR), and the elemental composition (SEM-EDX). In this article, the two techniques were used to analyze the composition of red ink in prints. As a result of these analyses, it was possible to distinguish among nearly all of the pigments and inks, indicating that the composition of the red ink can be reliably used to differentiate between stamps of different origins in a series of prints.

Identification of organic pigments in tattoo inks and permanent make-ups using MALDI-TOF mass spectrometry

“…So far the identification of tattoo pigments in inks has mainly been carried out using Raman as well as Fourier transform infrared (FT-IR) spectroscopy 7, 8 . Raman spectroscopy has also been used for matching the profile of tattoo inks with dermatome shave biopsies from patients with allergic reactions 9 .…”

“…While FT-IR and Raman Spectroscopy are very suitable for the identification of single pigments, their successful use for pigment mixtures, often present in tattoo inks, has yet to be proved. Matrix assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF–MS) has been reported for identifying pigments in automotive coatings 11 or art work 8, 12– 14 . In this article, we present a validated MALDI-TOF-MS approach for the identification of pigments in tattoo inks and PMUs.…”

Elemental analysis of Chinese red seal inks on xuan paper by ArF laser-induced plume fluorescence

“…Both techniques are sensitive to the vibrational signature of the inorganic pigments [11]. When these vibrational analysis are performed together with elemental analysis, numerous red inks can be sorted unambiguously [8]. Yet once again, the destructiveness of the elemental analysis step is a concern.…”

“…Yet once again, the destructiveness of the elemental analysis step is a concern. For example, energy dispersive x-ray (EDX) analysis will require the extraction of ink sample from the artwork for insertion into the analysis chamber [8]. The invasiveness can be reduced if techniques of higher sensitivity are adopted, such as time-of-flight secondary ion mass spectrometry (TOF-SIMS) [12].…”

“…For the organics, chromatographic separation such as thinlayer [6], high-performance [7], and gas chromatography [7], followed by fluorescence or mass spectrometry are very effective methods of analysis. Transmission Fourier-transform infra-red (FTIR) spectroscopy is also useful in identifying specific bonds [8].…”