Failure Analysis of Paper: Determination of the Chemical Identity of Impurities and Inclusions

Since many paper types have a very inhomogeneous composition and defects are often extremely small, the analysis with macroscopic measurement methods is usually not possible. With the aid of an FTIR microscope, it is possible to measure an IR-spectrum anywhere on the sample with a high lateral resolution and thereby to determine the chemical composition of the defect. A mapping measurement allows the qualitative analysis of the components and the determination of the distribution on the measured sample area.