title: Improvement in latent fingerprint detection on thermal paper using a one-step ninhydrin treatment with polyvinylpyrrolidones (PVP).
abstract: Most thermosensitive surfaces of thermal paper turn black when they come into contact with polar organic solvents such as are used in ninhydrin petroleum benzin solution. This dark staining reduces the contrast between the developed fingerprint and the background to such an extent that the identification process becomes very difficult. Integrating polyvinylpyrrolidones (PVP) into a ninhydrin solution prevents the black staining, and the developed fingerprints appear in clear contrast to the background. The new ninhydrin solution containing PVP is successful compared to the two-step ninhydrin-acetone washing method for thermal paper which is popular in Germany.
authors.affiliation: KT 41-2 Research, Development, and Testing of Fingerprint Detection Methods, Kriminaltechnisches Institut des Bundeskriminalamts, 65173 Wiesbaden, Germany. Lothar.Schwarz@bka.bund.de
authors.forename: Lothar
authors.initials: L
authors.lastname: Schwarz
authors.forename: Inga
authors.initials: I
authors.lastname: Klenke
mesh_terms: D000438:Alcohols; D000473:Alkanes; D003510:Cyclohexanes; D003878:Dermatoglyphics; D006536:Heptanes; D006586:Hexanes; D006801:Humans; D007202:Indicators and Reagents; D009555:Ninhydrin; D010209:Paper; D010420:Pentanes; D010578:Petroleum; D011205:Povidone
chemical_list: D000438:Alcohols; D000473:Alkanes; D003510:Cyclohexanes; D006536:Heptanes; D006586:Hexanes; D007202:Indicators and Reagents; D010420:Pentanes; D010578:Petroleum; C026385:n-hexane; C506365:Cyclohexane; C033353:pentane; D011205:Povidone; D009555:Ninhydrin; C004544:naphtha