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Developing Methods To Improve the Quality and Efficiency of Latent Fingermark Development by Superglue Fuming

NCJ Number
Date Published
May 2014
41 pages
This is a report on research designed to improve the superglue fuming method of developing latent fingermarks.
The research optimized the acquisition of developed latent fingermarks and improved the quality of aged fingermarks. This was done by using researchers' expertise in polymer chemistry to explain the role of temperature on the superglue fuming of aged fingermarks and developing protocols to implement temperature control in a forensic laboratory. The results show that fuming at lower temperatures improves the rate of polymerization that occurs during superglue fuming. The optimum temperature of fuming is between 10 and 15 degrees centigrade. Any protocols that are devised to control the temperature of fuming must take into account the presence of the warm superglue fumes. The decrease in temperature also apparently improves the quality of aged latent prints. Previous results also suggest that rehydrating an aged fingermark is critical to its successful development by superglue fuming. The current study investigated aggressive rehydration methods of aged latent fingermarks as a method to improve the quality of aged prints. It was found, however, that rehydrating fresh or aged prints by exposure to room temperature or boiling water vapor is not a sufficient method for improving print quality. Exposure to boiling water vapor harms prints, presumably by removing initiators by dissolving them into the steam and releasing them from the print before fuming. Researchers completed Fourier Transform Infrared spectroscopy experiments to monitor the molecular level changes during the polymerization of ethyl cyanoacrylate and the hardening process that occurs after polymerization. This provides guidelines that can be used to improve the turn-around time for obtaining a print that can be recorded and compared to a database. 16 figures, 2 tables, and 34 references

Date Published: May 1, 2014