A study of German printing inks from the early 20th century

Various coulorful printing inks were developed and widely distributed during the 19th and 20h centuries. However, in comparison to artists' paints from that period, printing inks are not studied in depth. This paper provides a first insight into materials in common German printing inks used at the time to understand the artists' opportunities, predict properties such as light fastness and possible colour alterations. The study is based on literature research and the analysis of two printing ink sample books from the 1920s and 1930s. Complementary analytical techniques were employed to characterise the ink samples, namely Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, Gas Chromatography-Mass Spectrometry (GC-MS) and Scanning Electron Microscopy-energy dispersive X-ray spectroscopy (SEM-EDS). Twenty modern synthetic organic pigments (SOPs) and several traditional pigments as well as metallic pigments were identified in the catalogues. Linseed oil, semi-drying oils and resins (such as Copal and Dammar) were used as binding media. The results will aid decision-making in preservation and conservation of printed works.