Effect of silver (Ag) deposition before physical developer to develop latent fingerprints on wet paper

초록

Latent fingerprints on wet paper cannot be developed using amino acid reaction reagents. Therefore, physical developer (PD) or lipid staining reagents like oil red O (ORO) should be utilized. However, ORO is not very effective in developing fingerprints that are older than approximately 4 weeks. On the other hand, PD performs well in developing older fingerprints, but it cannot do so for relatively fresh fingerprints. Additionally, PD has the disadvantage of taking a long time to develop fingerprints. In this study, in order to overcome the limitations of PD, we attempted to increase its reactivity by applying Ag-PD, which involves depositing silver onto paper using vacuum metal deposition (VMD), and compared this with fingerprints developed using ORO and PD. As a result, Ag-PD showed superior fingerprint development compared to ORO and PD on wet paper stored for 2-8 weeks, and the fingerprint development time for PD was significantly reduced to 90 similar to 150 seconds.

키워드