Detection of latent fingermarks on thermal printer paper by dry contact with 1,2-indanedione

Abstract

A new method for the detection of latent fingermarks on thermal paper by dry contact with 1,2-indanedione, which reacts with the amino acids present to give coloured, photo luminescent prints is described. The simple and reliable method is based on contact between the thermal paper sample and reagent impregnated treatment papers. Different treatment paper reagent formulations and treatment times were investigated. The conditions which provided the best performance used treatment papers prepared from an acid-free fluorous solution containing 1,2-indanedione and zinc chloride, with a contact time of 48 h. The dry contact approach was compared to current methods used by law enforcement agencies within Australia and was found to give similar or better performance.