CLASSIFICATION AND IDENTIFICATION OF PHOTOCOPYING TONERS BY DIFFUSE REFLECTANCE INFRARED FOURIER-TRANSFORM SPECTROSCOPY (DRIFTS) .1. PRELIMINARY-RESULTS

A diffuse reflectance infrared Fourier transform technique is described for the analysis of raw photocopying toners and small samples of toner removed from the surface of a photocopied document. The technique gives reproducible results and makes possible differentiation of toner samples obtained from different photocopying machines. In addition, toners may be classified into a number of groups, based on the presence or absence of certain absorption bands in their diffuse reflectance spectra. Preliminary results indicate the feasibility of a database of infrared spectra for the photocopying toners available on the market. Such a database would be a valuable aid to the document examiner in the increasing number of cases involving photocopies.