NCJ Number
217627
Journal
Journal of Forensic Identification Volume: 57 Issue: 2 Dated: March/April 2007 Pages: 240-243
Date Published
March 2007
Length
4 pages
Annotation
This study examined various types of cellophane tape to determine which one worked best in clearing the background discoloration of thermal paper.
Abstract
Results of the study showed that frosted tapes worked the best in clearing the background discoloration of thermal paper. Thermal paper is a special type of paper used for cash register receipts. Dyes contained in one of the layers of thermal paper are released by heat from a separate thermal print head, thus producing an image. The solvents used as carriers for the ninhydrin mixtures react with the dye layer, causing damage to the paper and obscuring any possible latent prints. Covering the latent print on thermal paper with certain brands of cellophane tape provides an easy way to clear the discoloration caused by ninhydrin processing. This study examined various types of cellophane tape to clear the background discoloration of thermal paper that occurs with wet ninhydrin processing and determines which type of cellophane tape worked best in clearing the background. Figures, references