The Forensic Analysis of Skin-Safe Stamp Pad Inks

Author

Swetha Rajagopal, CUNY John Jay CollegeFollow

Date of Award

Spring 5-2019

Document Type

Thesis

Degree Name

Master of Science (MS)

Department/Program

Forensic Science

Language

English

First Advisor or Mentor

Thomas A. Kubic

Second Reader

Michelle D. Miranda

Third Advisor

John R. Lombardi

Abstract

Skin-safe stamp pad inks are currently being used at locations such as clubs, zoos and other events with the purpose of stamping individuals that visit the location. This is done in an attempt to monitor the number and activity of visitors. Ink manufacturing companies generally tend to experiment with a number of different combinations of the different components of ink, in order to obtain desirable properties. The combinations are usually proprietary and that very nature of the inks ends up making them, possibly unique and individual. The analysis, identification and possible individualization of the chemical composition of these inks could play a significant role in providing crucial evidential information to investigators in forensic cases. The aim of this research was to scientifically evaluate these inks by documenting the physical properties of the inks both macroscopically and microscopically and by identifying the optical and chemical properties of the ink components spectroscopically. The application of Ultraviolet-Visible (UV-VIS) Spectroscopy and Fourier-transform Infrared Spectroscopy (FT-IR) to the analysis of skin safe stamp pad inks sold for temporary tattooing purposes, has been explored in this project.

Results from this study indicated that each step of the analysis and each technique used by itself, was powerful to get us closer and closer to a full discrimination of the ink samples and by combining the steps, all the analyzed samples were successfully discriminated. The results from this research can be used as reference spectra for potential skin-safe stamp pad ink forensic evidence. Furthermore, the use of the Bio-Rad software to make positive correlations with the reference samples listed in the software’s extensive database acted as a key first step towards possibly determining the identity of iii the components in the ink samples. Additional analysis using other techniques such as X-Ray fluorescence or Raman Spectroscopy could reveal more information about the different components of skin-safe inks.

Recommended Citation

Rajagopal, Swetha, "The Forensic Analysis of Skin-Safe Stamp Pad Inks" (2019). CUNY Academic Works.
https://academicworks.cuny.edu/jj_etds/110