MICROSPECTROSCOPY FTIR REFLECTANCE EXAMINATION OF PAINT BINDERS ON GROUND CHALK

A restorer's questions on chemical analysis of paint binders to suppor t his complicated work has always had an exceptional appeal for chemis ts. Non-destructive surface analysis of rather complex materials such as paint binders is possible. The advantages of vibrational spectrosco py related to the details about chemical structure of organic compound s have been combined with sophisticated methods of multivariate data a nalysis. Reflectance spectra of several paint binders on ground chalk were measured using a fast, sensitive FTIR spectrometer equipped with an infrared microscope. The initial reflectance spectra include suffic ient structural information to allow successful classification by hier archical cluster analysis (HCA). Similarities between the several bind ers are plotted as dendrograms which are well structured. Their explan ation will be discussed in detail. Finally the postulated feature sets will be checked up by principal component analysis (PCA) as to their relevance and information content.