Fourier Transformation Infra-Red (FT-IR) spectroscopy
The Infra-red spectrum of the binder of a product can be determined by an FT-IR spectrophotometer. A small (paint) flake or some droplets of the wet product are sufficient to obtain an accurate infra-red spectrum to identify the used binder.
The infra-red spectrum is a graph presenting the absorption or transmission of the radiation as a function of the applied energy or wave length.
The word fingerprint is frequently used for characterising a paint, and often only the infra-red spectrum is specified. In other cases (standards ISO 20340, NORSOK M-501, EN 10290, Shell DEP 30.48.00.32, Enercon QS tow 30-6b, ISO 15741) the infra-red spectrum is part of the fingerprint (the (chemical and physical) characterising of a paint).
FT-IR is used as an important instrument for trouble shooting to identify or exclude a specified (type of) coating.